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60f88b9c2082f5032c8e0d4b4d2aa699 | 101 127 | 9.3 Interference sensitivity | Under study. |
60f88b9c2082f5032c8e0d4b4d2aa699 | 101 127 | 9.4 Distortion sensitivity | Under study. |
60f88b9c2082f5032c8e0d4b4d2aa699 | 101 127 | 10 Branching, feeder and antenna requirements | The parameters and values specified in subclauses 10.2 to 10.5 are essential prerequisites for the system specification given in the present document. |
60f88b9c2082f5032c8e0d4b4d2aa699 | 101 127 | 10.1 Antenna radiation pattern envelopes | There are differing frequency management methods, differing traffic requirements and densities across European countries therefore the selection of a particular standard will be the responsibility of the administration in conjunction with the user and other relevant parties. Further study is required on this subject. |
60f88b9c2082f5032c8e0d4b4d2aa699 | 101 127 | 10.2 Cross-Polar Discrimination (XPD) | The value of XPD specified should be the same as in the AP arrangements in the same frequency bands, that is XPD ≥ 28 dB, allowing the use of the same antennas. It must be noted that some critical hops could require greater values of XPD. Further study is required on this subject. TR 101 127 V1.1.1 (1997-11) 20 |
60f88b9c2082f5032c8e0d4b4d2aa699 | 101 127 | 10.3 Intermodulation products | Each intermodulation product caused by different transmitters linked to the same antenna should be less than -110 dBm referenced to point C with an output power relevant to the Classes A to D (table 1) per transmitter. |
60f88b9c2082f5032c8e0d4b4d2aa699 | 101 127 | 10.4 Interport isolation | Not less than 40 dB. |
60f88b9c2082f5032c8e0d4b4d2aa699 | 101 127 | 10.5 Return loss | Not less than 24 dB at the feeder flange (points C, C') with antenna connected. |
60f88b9c2082f5032c8e0d4b4d2aa699 | 101 127 | 10.6 Antenna / equipment / feeder flanges | When wave guides are required IEC PDR type flanges (rectangular) should be used as below: Frequency Band [GHz] 4 L6 7 8 13 14 15 PDR Flange Type 40 70 70/84 84 120 140 14 |
60f88b9c2082f5032c8e0d4b4d2aa699 | 101 127 | 11 Cross polar interference sensitivity | This clause covers specific aspects of the performance of the system in presence of cross polarisation interference not covered in the previous clauses. |
60f88b9c2082f5032c8e0d4b4d2aa699 | 101 127 | 11.1 Co-channel "internal" interference sensitivity in flat fad | ing conditions For frequency bands given under subclause 5.1, the limits of the co-channel "internal" interference sensitivity for systems A and B should be as in figures A.6a and A.6b respectively. Values of XIF used for curves in these figures have been derived from subclause 1.3. |
60f88b9c2082f5032c8e0d4b4d2aa699 | 101 127 | 11.2 Co-channel "internal" interference sensitivity in dispersi | ve fading conditions The subject is still under study. A preliminary procedure for evaluating XPIC performance in this conditions is given in subclause 1.3. TR 101 127 V1.1.1 (1997-11) 21 Annex A: Figures -110 -100 -90 -80 -70 -60 -50 -40 -30 -20 -10 0 10 0 10 20 30 40 50 60 70 Frequency offset from actual centre frequency [MHz] Power Spectral Density [dB] a) b) c) dB / MHz +1 / 11.5 -6 / 14.5 -32 / 17 -32 / 18 -45 / 22 -65 / 34 -85 / 32 -95 / 40 -105 / 60 Figure A.1a: Spectrum masks for normal channels (b) for frequency bands with 29, 29,65 and 30 MHz spacing, and inner edges of innermost channels (c) for L6 GHz band. System A TR 101 127 V1.1.1 (1997-11) 22 0 10 20 30 40 50 60 70 -110 -100 -90 -80 -70 -60 -50 -40 -30 -20 -10 0 10 Frequency [MHz] Power Spectral Density [dB] (a) (b) (c) +1/11.5 -10/14.5 -32/16 -32/17 -45/20 -65/28 -105/42 -105/60 dB/MHz Figure A.1b: Spectrum masks for normal channels (b) and inner edges of innermost channels (c) for frequency bands with 28 MHz spacing and 56 MHz centre gap. System A TR 101 127 V1.1.1 (1997-11) 23 0 10 20 30 40 50 60 70 -120 -110 -100 -90 -80 -70 -60 -50 -40 -30 -20 -10 0 10 Frequency [MHz] Power Spectral Density [dB] (a) (b) +1/13 -50/15 -50/20 -65/30 -110/60 dB/MHz Figure A.2a: Spectrum masks for the normal channels for frequency bands with channel spacing of 28 MHz. System B TR 101 127 V1.1.1 (1997-11) 24 0 10 20 30 40 50 60 70 -120 -110 -100 -90 -80 -70 -60 -50 -40 -30 -20 -10 0 10 Frequency [MHz] Power Spectral Density [dB] dB/MHz +1/10 -12.5/13.5 -50/15 -50/20 -110/35 Figure A.2b: Spectrum masks for the inner edges of innermost channels in the L6 GHz band and 56 MHz centre gap in the 7 GHz band. System B TR 101 127 V1.1.1 (1997-11) 25 -1 1 0 -1 0 0 -9 0 -8 0 -7 0 -6 0 -5 0 -4 0 -3 0 -2 0 -1 0 0 1 0 0 1 0 2 0 3 0 4 0 5 0 6 0 7 0 F re q u e n c y o ffs e t fro m a c tu a l c e n tre fre q u e n c y [M H z ] R e c e iv e r S e le c tiv ity [d B ] d B / M H z + 1 / 1 1 .5 -6 / 1 4 .5 -3 2 / 1 7 -4 5 / 2 0 -4 5 / 2 2 -1 0 5 / 3 6 Figure A.3a: Limits for the receiver selectivity for the inner edges of innermost channels in the L6 GHz band. System A TR 101 127 V1.1.1 (1997-11) 26 0 10 20 30 40 50 60 70 -120 -110 -100 -90 -80 -70 -60 -50 -40 -30 -20 -10 0 10 Frequency [MHz] Receiver Selectivity [dB] dB/MHz +1/10 -12.5/13.5 -50/15 -50/20 -110/35 Figure A.3b: Limits for the receiver selectivity for the inner edges of innermost channels in the L6 GHz band and in the 7 GHz band with 56 MHz centre gap. System B TR 101 127 V1.1.1 (1997-11) 27 25 30 35 40 -75 -70 -65 -60 S/I referred at point B [dB] Receiver Input Level at Point B [dBm] <10Ghz 13GHz 14/15GHz <10GHz 13GHz 14/15GHz BER=10-3 BER=10-6 Figure A.4a: Co-channel digital "external" interference sensivity masks. System A TR 101 127 V1.1.1 (1997-11) 28 25 30 35 40 -70 -65 -60 -55 S/I referred at point B [dB] Receiver Input Level at Point B [dBm] 7GHz 13GHz 14/15GHz 7GHz 13GHz 14/15GHz BER=10-3 BER=10-6 Figure A.4b: Co-channel "external" digital interference sensivity masks. System B TR 101 127 V1.1.1 (1997-11) 29 -15 -10 -5 0 -75 -70 -65 -60 S/I referred at point B [dB] Receiver Input Level at Point B [dBm] <10Ghz 13GHz 14/15GHz <10GHz 13GHz 14/15GHz BER=10-3 BER=10-6 Figure A.5a: Adjacent-Channel digital interference sensivity masks. System A TR 101 127 V1.1.1 (1997-11) 30 -20 -15 -10 -5 -70 -65 -60 -55 S/I referred at point B [dB] Receiver Input Level at Point B [dBm] 7GHz 13GHz 14/15GHz 7GHz 13GHz 14/15GHz BER=10-6 BER=10-3 Figure A.5b: Adjacent-Channel digital interference sensivity masks. System B TR 101 127 V1.1.1 (1997-11) 31 5 10 15 20 -75 -70 -65 -60 S/I referred at point B [dB] Receiver Input Level at Point B [dBm] <10Ghz 13GHz 14/15GHz <10GHz 13GHz 14/15GHz BER=10-3 BER=10-6 Figure A.6a: Co-Channel "internal" digital interference sensivity masks. System A TR 101 127 V1.1.1 (1997-11) 32 5 10 15 20 -70 -65 -60 -55 S/I referred at point B [dB] Receiver Input Level at Point B [dBm] 7GHz 13GHz 14/15GHz 7GHz 13GHz 14/15GHz BER=10-3 BER=10-6 Figure A.6b: Co-Channel "internal" digital interference sensivity masks. System B TR 101 127 V1.1.1 (1997-11) 33 Annex B: Bibliography The following material, though not specifically referenced in the body of the present document, gives supporting information. - ITU-R Recommendation F.382-6: "Radio-frequency channel arrangements for radio-relay systems operating in the 2 and 4 GHz bands". - ITU-R Recommendation F.383-5: "Radio-frequency channel arrangements for high capacity radio-relay systems operating in the lower 6 GHz band". - ITU-R Recommendation F.386-4: "Radio-frequency channel arrangements for radio-relay systems operating in the 8 GHz band". - ITU-R Recommendation F.497-5: "Radio-frequency channel arrangements for radio-relay systems operating in the 13 GHz frequency band". - ITU-R Recommendation F.636-3: "Radio-frequency channel arrangements for radio-relay systems operating in the 15 GHz band". - ITU-R Recommendation F.750-2: "Architectures and functional aspects of radio-relay systems for SDH-based networks". - ITU-R Recommendation F.385-6: "Radio-frequency channel arrangements for radio-relay systems operating in the 7 GHz band". - ITU-T Recommendation G.707: "Network node interface for the synchronous digital hierarchy (SDH)". - ITU-T Recommendation G.774: "Synchronous Digital Hierarchy (SDH) management information model for the network element view". - ITU-T Recommendation G.784: "Synchronous digital hierarchy (SDH) management". - ETS 300 019, Parts 1 and 2: "Equipment engineering; Environmental conditions and environmental tests for telecommunications equipment". - ETS 300 119: "Equipment Engineering [EE]; European telecommunication standard for equipment practice". - ETS 300 385 : "EMC standard for DRRS fixed service". - ETS 300 132: "Equipment engineering; Power supply interface at the input to telecommunications equipments". - ETS 300 635: "Transmission and Multiplexing (TM); Synchronous Digital Hierarchy (SDH); Radio specific functional blocks for transmission of Mx STM-N". - ETS 300 645: "Transmission and Multiplexing (TM); Synchronous Digital Hierarchy (SDH) radio relay equipment; Information model for use on Q-interfaces". - R.Valentin, H.-G.Giloi, K.Metzger; "Co-Channel Cross-Polarized Operation of Digital Radio Systems"; Third European Conference on Radio Relay Systems (3rd ECRR);Paris-France, Dec. 17-20, 1991, pp 309-313. TR 101 127 V1.1.1 (1997-11) 34 History Document history V1.1.1 November 1997 Publication ISBN 2-7437-1821-8 Dépôt légal : Novembre 1997 |
94cc37b251e47c47264903912f7a4868 | 101 119 | 1 Scope | The present document is to describe Number Portability. For the purpose of this study Number portability is limited to the Service Provider Portability for Geographic Numbers (GNP) and Non Geographic Numbers (NGNP) in the National Fixed Network, e.g. number portability between Service Providers within geographic country boundaries. An exception to this is Number Portability of the European Telephony Numbering Space. In order to describe number portability, the present document provides: - an overview of number portability; - a description of the responsibility of the different entities involved; - a description of number portability in the European Telephony Numbering Space (ETNS); - background material to concepts used in related documents TR 101 118 [1], TR 101 122 [2] and EG NA-061501 [3] describing: - possible internal architectures; - numbering and addressing; - signalling; - Intelligent Network (IN) Options. The present document describes the responsibilities of the various entities involved in number portability in order to deliver calls to numbers that have been ported. The present document also identifies the information requirements of the various entities necessary to manage and implement Number Portability. Service management and inter-operator procedures have been demonstrated to be the major area of difficulty when introducing number portability. Detailed considerations of these issues are outside the scope of the present document The scope of the requirements is limited to: - the portability of individual customer numbers; - porting of individual Multiple Subscriber Number (MSN); - porting of complete Direct Dialling In (DDI) ranges. However, whilst it is not possible to port single numbers from a DDI range, dividing the range into blocks and porting the resultant sub block will have the same effect. Therefore there is no need to support the portability of individual numbers within a DDI range. The results of the study should ensure: 1) Architectural Flexibility: the set of architectures selected for support of number portability should allow network operators reasonable flexibility in the manner in which the architecture is implemented, the use of equipment from multi vendors; 2) Transparency: the mechanism by which portability is provided should be transparent to the ported and non ported customers; 3) Performance: the mechanism by which portability is provided should subject the call to minimal (if any) performance degradation relative to that offered to non ported numbers. This includes both post dial delay and transmission; 4) interconnection: All network operators offering portability within the same geographic area should interconnect, either directly, or via a transit, and complete calls. Direct or transit interconnection is a commercial decision. 6 TR 101 119 V1.1.1 (1997-11) The following Portability types are out of the scope of this study, but are described for completeness: - service Provider Portability for Mobile Numbers; - service Portability; - location Portability. The impact of a ported non geographic number resolving to a geographic number has been raised as an issue, and is for further study. |
94cc37b251e47c47264903912f7a4868 | 101 119 | 2 References | References may be made to: a) specific versions of publications (identified by date of publication, edition number, version number, etc.), in which case, subsequent revisions to the referenced document do not apply; or b) all versions up to and including the identified version (identified by "up to and including" before the version identity); or c) all versions subsequent to and including the identified version (identified by "onwards" following the version identity); or d) publications without mention of a specific version, in which case the latest version applies. A non-specific reference to an ETS shall also be taken to refer to later versions published as an EN with the same number. [1] TR 101 118 (1997): "High Level Network Architecture and Solutions to support Number Portability". [2] TR 101 122 (1997): "Numbering and Addressing for Number Portability". [3] Draft EG NA-061501: "IN & Intelligence Support for Service Provider Number Portability". [4] ITU-T Recommendation E.164: "The International Public Telecommunication Plan". [5] TR 101 073 (1997): "Number Portability for pan European Services". |
94cc37b251e47c47264903912f7a4868 | 101 119 | 3 Definitions and Abbreviations | |
94cc37b251e47c47264903912f7a4868 | 101 119 | 3.1 Definitions | |
94cc37b251e47c47264903912f7a4868 | 101 119 | 3.1.1 Entities | Network Operator: An entity that operates a network in order to route calls. Service Provider: An entity that offers services to users involving the use of network resources. The "Service Provider" is understood in the present document in a generic way and may have different status according to the service provided. For example, "Service Provider" refers to a local loop operator in the case of Geographic Numbers, or to a mobile operator in the case of Mobile Numbers, or to a service operator / reseller in the case of Service Numbers. |
94cc37b251e47c47264903912f7a4868 | 101 119 | 3.1.2 Service provider portability | Donor Service Provider: The Service Provider from whom the number was initially ported. Recipient Service Provider: The Service Provider to whom the number is ported. 7 TR 101 119 V1.1.1 (1997-11) Service Provider Portability for Geographic Numbers (also known as geographic number portability, GNP; also known as local number portability, LNP): A service that enables a customer to resign their subscription with a Service Provider and to contract another subscription with another Service Provider without changing their Geographic Number, without changing their location, and without changing the nature of the service offered. Service Provider Portability for Non-geographic Numbers (NGNP): A service that enables a customer to resign their subscription with a Service Provider and to contract another subscription with another Service Provider without changing their Non-geographic Number, and without changing the nature of the service offered. Service Provider Portability for Mobile Numbers: A service that enables a user to resign their subscription with his current Mobile Network Operator and subscribe to a competitor without changing their number. Service Provider Portability for Pan-European Services: A service that enables a user to resign their subscription with their current Pan European Service Provider and subscribe to a competitor without changing their number. |
94cc37b251e47c47264903912f7a4868 | 101 119 | 3.1.3 Location portability | Location Portability: A service that allows a customer to retain his Directory Number when changing their premises in a certain area. Four variants of location portability can be seen to exist: - within exchange area; - within numbering area; - within charge area; - anywhere. |
94cc37b251e47c47264903912f7a4868 | 101 119 | 3.1.4 Service portability | Service Portability: A service that allows a customer to retain their Directory Number when they are offered a new service, e.g. telephone service (fixed) to mobile telephone service (PLMN). |
94cc37b251e47c47264903912f7a4868 | 101 119 | 3.1.5 Numbers | DIRECTORY NUMBER GEOGRAPHIC NUMBER NON-GEOGRAPHIC NUMBER ETNS Number Mobile Number Service Number Other Non Geographic Number Figure 1: Relationship between Geographic and Non Geographic Numbers NB: These are examples of non geographic numbers only, and are not prescriptive Directory Number (DN): A number in the national numbering scheme that is allocated to a customer for a telephony service. Allocation of the Directory Number is made directly by the Numbering Plan Administration (NPA) to the customer, or indirectly when blocks of numbers are managed by Service Providers. The Directory Number is the number that is dialled by the users to reach the customer (potentially with prefix and/or with suffix). Geographic Number (GN): A Directory Number from that part of the national numbering scheme that is used to identify fixed line termination's. Prior to Number portability these numbers are geographical in that sense that they convey the location of the customer. Non-geographic Number (NGN): A Directory number that is not a Geographic Number. A Non-geographic Number does not imply the location of the customer. Mobile Number: A Directory Number from a specific range of the national numbering scheme reserved for customers to mobile service(s). 8 TR 101 119 V1.1.1 (1997-11) Service Number: A Directory Number from a specific range of the national numbering scheme reserved for specific category of services, e.g. premium rate services, personal numbers. While the definitions above refer to the identity of the customer for other users, the definition below refers to numbers used by the networks only. This definition is further developed in TR 101 122 [2] Routeing Number: A specific number that is added and used by the networks to route the call. The Routeing Number conveys information useably by the network. If the digits dialled by the user match the digits of a routeing number, the dialled digits should not be interpreted as a routeing number. Ported Number: A number that has been subject to number portability. |
94cc37b251e47c47264903912f7a4868 | 101 119 | 3.1.6 Networks | Donor Network: The initial Network where a number was allocated by the NPA before ever being ported. Recipient Network: The Network where a number is located after being ported. Transit Network: A network between two networks, e.g. . the recipient network and the donor network. Originating Network: The network where the calling party is connected. For most incoming international calls, the originating network is effectively the network containing the international gateway. For carrier selection, the first exchange of the selected carrier effectively becomes the originating network for routeing purposes. Serving Network: The network that determines whether a number has been ported, and, if so, provides an appropriate routeing number. This functionality may be distributed. |
94cc37b251e47c47264903912f7a4868 | 101 119 | 3.1.7 Exchanges | Donor Exchange: The initial Exchange where a number was located before ever being ported. Recipient Exchange: The new Exchange where a number is located after being ported. Transit Exchange: An exchange between two exchanges, e.g. . the recipient exchange and the donor exchange. Originating Exchange: The exchange where the calling party is located. For most incoming international calls, the originating exchange is effectively the international gateway. For carrier selection, the first exchange of the selected carrier effectively becomes the originating exchange for routeing purposes. |
94cc37b251e47c47264903912f7a4868 | 101 119 | 3.1.8 Functions | Range Analysis Function: The function whereby a number of significant digits of a number (Called Party or Routeing) are examined in order to determine the appropriate routeing to a destination entity. Call Trap Function: The function whereby a mechanism is employed to determine that a number may be ported. Database Query Function: The function whereby a database is accessed in order to ascertain whether a number is ported, and if it is, a Routeing Number is obtained that may be used to route the call to a destination. The database could form part of an IN implementation, could be embedded within the switch, or could be some form of other off-switch database. Number Translation Function: The function whereby a number (Routeing or Called Party), is translated to a destination number, possibly according to special conditions such as time of day, in order that calls can be completed. Routeing Number Addition Function: The function which identifies a recipient and adds the appropriate routeing number. 9 TR 101 119 V1.1.1 (1997-11) |
94cc37b251e47c47264903912f7a4868 | 101 119 | 3.1.9 Other definitions | Number Plan Authority (NPA): Entity that is responsible for the administration and the assignment of numbers, or number blocks, within a national numbering plan. National Numbering Plan: A national Numbering Plan is a scheme that structures the numbers used and the numbers space available in a country. Point of Interconnection: An access point between 2 Networks. Number Range Holder: An entity who is responsible for the administration and allocation of numbers within a particular range. ETNS Regulatory Authority: The body responsible for the regulation of services provided over the European Telephony Numbering Space. Geographic Number Portability: See Service Provider Portability for Geographic Numbers. Non Geographic Number Portability: See Service Provider Portability for Non Geographic Numbers. |
94cc37b251e47c47264903912f7a4868 | 101 119 | 3.2 Abbreviations | For the purposes of the present document the following abbreviations apply: CCBS Call Completion to Busy Subscriber EN European Number ENTF European Numbering Task Force ETNS European Telephony Numbering Space IN Intelligent Networks CEU Commission of the European Union MSN Multiple Subscriber Number DDI Direct Dialling In GNP Geographic Number Portability NGNP Non Geographic Number Portability NPA Numbering Plan Administration DN Directory Number RN Routeing Number 10 TR 101 119 V1.1.1 (1997-11) |
94cc37b251e47c47264903912f7a4868 | 101 119 | 4 Objectives | The following objectives have been used in developing solutions. Objective Rationale Seek and develop internationally standardized solutions as far as possible. C7 signalling is based upon international standards and the objective is to evolve in line with standards (avoid proprietary solutions as far as possible). number portability solutions therefore need to be established internationally in order to facilitate standards development. To allow a multivendor environment. Focus upon interconnect (inter-network) standards rather than intra-network solutions. Operators need to be in control of its own network architecture and signalling systems. Solutions that “standardize” the inter-network relationship allow that freedom. Seek and develop solutions that enable operators, as far as possible, to remain in control of its own network call control processes. The network operator should not be required to be dependant upon another operator or organization for the real-time control of its network. Solutions should not be based upon specific technologies. Technology will advance rapidly whilst interconnect agreements will change at a slower pace. Solutions should avoid use of specific technologies. Standardise basic building blocks and functions rather than monolithic solution. The solutions for number portability need to meet different regulatory and technical requirements. The solutions standardized should be capable of satisfying different network architectures and regulatory requirements. In a multi-operator environment solutions should allow operators to decide on a commercial basis if they wish to perform number portability functions. Clearly there has to be a base requirement which will have to be met by the set of operators involved. Co-existing phased solutions. The network operator will require the rapid introduction of number portability based upon EXISTING infrastructure. Solutions should be capable of rapid deployment and be capable of evolving towards a long-term solution. Each phase should be capable of co-existing with previous ones. No compulsion on an operator to have to upgrade. Address solutions for both connection control (basic call routeing) as well as for non-call/circuit associated services. Current number portability solutions focus upon call routeing. There are significant problems associated with the support of services like Call Completion to Busy Subscriber (CCBS) which will need to operate across network boundaries and between networks in different regulatory domains where different overall solutions may exist for number portability. 11 TR 101 119 V1.1.1 (1997-11) |
94cc37b251e47c47264903912f7a4868 | 101 119 | 5 Introduction | Generally, a directory number is considered to be ported when a major change occurs to the subscription of a customer, but the customer retains their assigned number(s). Depending on the kind of subscription change the following types of number portability can be identified: - service portability; - service Provider portability; - location portability. From the customers point of view all three types of number portability are desirable because a change of directory number(s) is usually linked with considerable inconvenience and expense. In principle, the technical issues are the same for all types of number portability, but there are some differences. For example, location portability and service portability may be implemented within one operator’s network domain - whereas Service Provider portability requires inter-network specifications and agreements. It is possible to combine the types of number portability, but this maybe subject to regulatory approval and is outside the scope of the study of which the present document is part. |
94cc37b251e47c47264903912f7a4868 | 101 119 | 5.1 Location portability | Location Portability is only applicable to geographic numbers, as by their nature, non geographic numbers do not incorporate location information. Unless combined with other types of portability, location portability is an internal network operator matter. Different scopes of location portability result in varying levels of complexity: - porting within an exchange area and within a charging area impacts neither network routeing nor billing; - porting within an exchange area but outside the charging area has implications for billing but not for network routeing; - porting outside the exchange area but within the charging area impacts network routeing but not billing. This is only the case where operators have common charging areas; if they do not, the forth bullet applies; - porting outside the exchange and charging area has implications for both routeing and billing. Geographic Numbers represent those numbers that imply the provision of a service to a specific geographic area and can be analysed by the calling party to determine the tariff. Operators generally allocate geographic numbers for PSTN/ISDN service (domestic and business) and according to the topology of their network. These numbers are generally allocated in blocks (e.g. 10,000 numbers) to individual local exchanges within a specific charge area. Thus limited location portability may be possible within these constraints; there is a need, however, to consider the implications of subsequent porting. Billing is impacted where the significant digits of the ported number no longer give an accurate reflection of the location of the terminal/customer for charging purposes. Routeing can be impacted, because the significant digits of the ported number can no longer be used to identify the exchange on which the number is hosted. Provision of location portability is beyond the scope of the present document. |
94cc37b251e47c47264903912f7a4868 | 101 119 | 5.2 Service portability | Service portability is a network operator option to provide additional features of a network operator’s service portfolio. Consideration should be given to charging implications, e.g. a freephone number should not ported to a premium rate service, unless some warning is given to callers of additional charges. Service portability is beyond the scope of the present document. 12 TR 101 119 V1.1.1 (1997-11) |
94cc37b251e47c47264903912f7a4868 | 101 119 | 5.3 Service provider portability | Service Provider Portability may be provided for geographic numbers and for non-geographic numbers, and allows customers to change Service Provider whilst retaining the same number. The present document concentrates on this type of portability. |
94cc37b251e47c47264903912f7a4868 | 101 119 | 5.4 Concatenation of types of number portability | Concatenation of types of portability can have implications if the customer wishes to revert to the original set-up; e.g. Service Provider portability followed by location portability may make it impossible for the customer to revert to the original donor Service Provider, as the donor may not offer location portability to the extent of the domain of that offered by the recipient Service Provider (i.e. it is not possible to move so far in the donor provider hence it is impossible to revert service). Table 1 shows the applicability of each type of portability to each type of number range. Table 1: Applicability of type of portability 1 Number Ranges 2 3 Type of Portability Geographic Non-Geographic Mobile Operator or Service Provider Location Restricted, depending upon network configuration and tariffing (notes 1 and 2) Not applicable note 3 Not applicable note 3 Service (note 4) (note 4) (note 4) The following should be noted: NOTE 1: See previous text on location portability. NOTE 2: Location Portability can be provided by an operator as a service in its own right, e.g. call forwarding. NOTE 3: Location portability is not relevant to services that have no geographic significance. NOTE 4: Allowed only if tariffing and regulatory constraints are met. |
94cc37b251e47c47264903912f7a4868 | 101 119 | 5.5 Number portability domains | When examining Number portability, it is instructive to consider the domains to which it applies. In addition to the portability domain, i.e. the scope of portability, there is another domain, the routeing Domain, which describes that part of the network(s) that is able to recognize a number as ported, and route accordingly. In figure 2, area ‘P’ is the domain over which it is possible to port a number, area ‘R’ is that part of the network that recognizes a number is ported, and carries out appropriate action (NB: for portability in the fixed network this routeing domain could well include mobile networks). Domain W describes the rest of telecom network, that has no way of detecting a number is ported, and therefore should route using normal principles. For location and service portability, domain ‘R’ is likely to be the extent of a single operator’s network. For portability of national numbers domain ‘R’ is likely to be at most the national boundary. For portability of ETNS, domain ‘P’ will be the networks of all CEPT countries, and ideally domain ‘R’ should be of the same extent. 13 TR 101 119 V1.1.1 (1997-11) P R W Figure 2: Domains A DN can only be ported when certain restrictions are not overruled. These define the portability (p). Example possibilities for the definitions of the portability domain could be: 1) a Geographical area (e.g. domain of a local exchange, an NDC or a country etc.), a user may only port the Directory Number if not moving outside the geographic area; 2) a Charging Zone, a user may only port the Directory Number if not moving outside the charging zone; 3) a user may only have their directory number ported if the type of telecommunication does not change, e.g. Freephone to premium rate, or telephone service (fixed) to mobile telephone service (PLMN). From the above one can understand that one of the reasons for restricting NP to a NP domain could be to prevent a caller, originating a call to a ported number, from being charged other than it is indicated by the dialled number. The Network scenario in figure 3 below gives an example of 3 portability domains, whereby a user can not port the directory number when moving between the domains. Portability domain PA Service Provider 1 Service Provider 3 Portability domain PC Service Provider 7 Service provider 1 Service Provider 5 Service Provider n Service Provider 3 Service Provider 1 Portability domain PB Figure 3: Principals associated with number portability domains 14 TR 101 119 V1.1.1 (1997-11) |
94cc37b251e47c47264903912f7a4868 | 101 119 | 6 Overview of number portability | |
94cc37b251e47c47264903912f7a4868 | 101 119 | 6.1 What is a number? | When number portability is discussed, number is taken to have the meanings defined in ITU-T Recommendation E.164.[4] |
94cc37b251e47c47264903912f7a4868 | 101 119 | 6.2 Generic assumptions for number portability | Solutions to support number portability should allow rapid deployment of number portability in such a manner that Service Providers can migrate between technical solutions. Solutions should be developed such that technology should not be presented as a barrier to implementing number portability. Each operator decides about their own network architecture, network functions and design of internal interfaces, as long as external requirements are fulfilled. This subclause lists some general requirements and limitations related to the number portability. In some cases (e.g. privacy) the requirements an the limitations are partially in conflict. 1) Only the ITU-T Recommendation E.164 [4] number (not including prefixes, suffixes, etc.) should be considered eligible to be ported. 2) The entire ITU-T Recommendation E.164 [4] number and not only part of it should be ported. 3) In some case not a single ITU-T Recommendation E.164 [4] number but a collection of ITU-T Recommendation E.164 [4] numbers may be requested to be ported 4) The privacy of the user which has ported his/her number should be granted. That means that the calling party should not be informed that the called party has ported his number. 5) Number portability should not affect the call dialling procedures. 6) When line identity presentation is required it shall be the directory number. 7) Introducing Service Provider portability should not adversely affect conformance with national or international propagation and echo standards. 8) Ensure that the preferred solutions are compatible with one another and provides a migration path between introductory solutions and long term solutions. |
94cc37b251e47c47264903912f7a4868 | 101 119 | 6.3 How is number portability generically performed | A number of entities are involved when describing number portability. The responsibilities of these entities are described more fully in clause 7. The information concerning number portability is transmitted between these entities by means of a routeing number. 15 TR 101 119 V1.1.1 (1997-11) incoming call (either from customer line or other network) Serving Network Serving Exchange Recipient Network Recipient Exchange 2nd step of the Routeing process, based on routeing number 1st step of the Routeing process, based on dialled digits Customer with ported number Note : The serving Network may be the originating Network and/or the donor network, and/or a transit network Transit Network (optional) Figure 4 Conceptual Framework for Incoming Calls The routeing number associated with a ported call has a structure associated with it. Looking at the information contained in the Routeing number TR 101 073 [5], 2 different cases can be identified: Complete Routeing Number (CRN) and Partial Routeing Number (PRN). In case of portability for geographic numbers Complete Routeing Number means that the Routeing Number got by the Serving exchange contains enough information to route the call to the Recipient Exchange. Likewise Partial Routeing Number means that the Routeing Number obtained by the Serving Exchange does not contain enough information to the route the call to the Recipient Exchange. That implies the need of subsequent translations that may take place in the Transit Network or in the Recipient Network to get the Routeing information to complete the call. In case of portability for non-geographic numbers the distinction between Complete Routeing Number and Partial Routeing Number is less important. In fact the Routeing number obtained by the Serving Exchange has to identify not a specific exchange but only the Service Provider who is responsible for the provision of the service associated with the non-geographic number. In this case we can assume that the Routeing number is always a Complete Routeing Number that is the Service Provider can be identified without subsequent translations. |
94cc37b251e47c47264903912f7a4868 | 101 119 | 6.4 Implications of number portability | The Numbering Plan Administrators allocates numbers in blocks, and routeing for the connection oriented services and non circuit signalling related services (e.g. CCBS) is based on these numbers. Number Portability breaks down this relationship based on these blocks. When customers are allowed to port their directory number between operators, the number of customers per number series in a given exchange becomes much lower than previously since the total number of connected customers to a particular number series will then be shared by a number of exchanges and operators. Another effect of number portability is that the same number series (e.g. 10,000 block of customer numbers) will now exist in many exchanges. With location portability this means that after a time all number series in the portability domain could exist in all local exchanges serving this domain. 16 TR 101 119 V1.1.1 (1997-11) A third effect of number portability is that one particular exchange will need to maintain many more number series than previously; this is to support the same number of customers connected, due to the lower number of customers per number series. Implementing number portability has operation and maintenance implications for operators. Procedures are required to support operators perform number portability. These procedures could include: Process Activity Steps to be covered Service Establishment Initial Contact Planning Stage Implementation Planning Network Implementation and Testing Service Maintenance introduction of a new switch introduction of a new number block number change new routeing number Service Ordering Requests, validation, scheduling, contingency plans, hours, subsequent mobility, change of account name, reasons for rejection Installation Cancellation Fault and repair handling Directory Number Information Directory entries, operator assistance emergency service Billing The introduction of number portability will have implications for the administration of numbers by the NPA in-order to support the procedures and process stated above. The perceived implication will depend upon regulatory decisions and how the numbers are allocated i.e. on block or individually. |
94cc37b251e47c47264903912f7a4868 | 101 119 | 7 Responsibilities | |
94cc37b251e47c47264903912f7a4868 | 101 119 | 7.1 General | A Service Provider acting as a recipient Service Provider, should be able to reciprocate, i.e. the same Service Provider should be able to act as a donor Service Provider. The mechanism by which an Service Provider supports number portability is the responsibility of the Service Provider. However all Service Providers shall have the following responsibilities placed upon them: - service Providers should keep audible records, for example to be able to locate the ported customer for malicious call intercept; - a Service Provider is responsible for their own customer base. However procedures need to be in place between the recipient , and the donor Service Provider to ensure effective and timely responses to customers; - escalation procedures need to be in place. The exact nature of these processes need to be documented in the interconnect agreement of the Service Providers concerned; - collecting and exchanging data necessary to support accounting should be accomplished. Where number ranges are assigned to Service Providers, the donor Service Provider will receive the number back from the recipient Service Provider when the customer: - relinquishes the number, e.g. moves outside the original number area(if this is not allowed), or ceases to be an active service customer. When a customer seeks to port their number a second time, creating a chain of donor Service Providers shall not occur. 17 TR 101 119 V1.1.1 (1997-11) |
94cc37b251e47c47264903912f7a4868 | 101 119 | 7.2 Service provider portability of geographic numbers | |
94cc37b251e47c47264903912f7a4868 | 101 119 | 7.2.1 Network operator responsibilities | In this subclause the responsibilities to route a call to the ported number are described. Originating Network The Originating Network is the network where the call is originated. It should be noted, however, that for the purposes of the present document, where carrier selection is employed, the selected carriers network becomes the Originating Network. Hence the network to which the caller is directly connected shall not perform any Number Portability Function. The originating network could also be the Recipient Network or a Serving Network, in which case routeing functions as described in the relevant subclauses below should be carried out. Otherwise, the Range Analysis Function should be carried out to route the call towards the Donor Network, possibly via a Transit Network. Transit Network The Transit Network should carry the call between two other networks. The Transit Network may or may not be acting as a Serving Network; if it is, it should carry out functions as described in the Serving Network section. If it is not, the Transit Network should: - if there is a routeing number previously added by another network, carry out the Range Analysis Function on this routeing number to route the call towards the recipient network (possibly via another Transit Network); - if no routeing number has been previously added, carry out the Range Analysis Function on the called party number to route the call towards the donor network (possibly via another Transit Network). Donor Network There are no specific requirements of the Donor Network, unless it is acting as a Serving Network. Recipient Network The Recipient Network should use the routeing number to route the call to the ported customer line; this could either by directly using the Range Analysis function for the routeing number, or by use of the Database Query function. Serving Network The Serving Network Functionality may be split across multiple networks, and may reside in the Originating, Transit or Donor network. The following functionality should be carried out: - the Call Trap Functionality should be carried out to determine that a number may be ported. This could be carried out by identifying a range containing ported numbers, or be specifically for a ported number; - the Database Query Function should be carried out to determine a routeing number; - the Routeing number addition function is added; - the Range Analysis Function should be carried out on the routeing number to direct the call towards the Recipient Network (possibly via a Transit Network). |
94cc37b251e47c47264903912f7a4868 | 101 119 | 7.2.2 Service provider responsibilities | In this subclause the responsibilities related to the service provision and number management are described. Donor Service Provider The donor Service Provider should not reallocate ported numbers to another customer. When evolution changes in the number plan affects a ported number, the effects should be specified in the interconnect agreement. 18 TR 101 119 V1.1.1 (1997-11) Recipient Service Provider When evolution changes in the number plan affects a ported number, a migration path needs to be agreed with the entities involved. The entities involved depends upon the specific implementation. The recipient Service Provider will inform the donor Service Provider of a change of circumstances that may affect calls being delivered to a ported number. A recipient Service Provider will ensure that a customer should not experience any limitations in the service offered by a Service Provider whether his/her number is ported or not. While the exact nature of the service offered to a ported customer is a commercial matter to be decided upon by the recipient Service Provider, if the recipient Service Provider offers a similar service to customers who have not ported their number, then they should have the ability to offer the same functionality, irrespective of whether the number has been ported or not, if the Service Provider wishes. Customers will get access to the services determined by the Service Provider to whom they are connected, irrespective of whether their number has been ported or not. The Recipient Service Provider has to provide sufficient information on outgoing calls such that the actual physical line being used, e.g. to enable Malicious Call Identification to occur. |
94cc37b251e47c47264903912f7a4868 | 101 119 | 7.3 Service provider portability of non geographic numbers | |
94cc37b251e47c47264903912f7a4868 | 101 119 | 7.3.1 Network operator responsibilities | In this subclause the responsibilities to route a call to the ported number are described. Originating Network The Originating Network is the network where the call is originated. It should be noted, however, that for the purposes of the present document, where carrier selection is employed, the selected carrier’s network becomes the Originating Network. The originating network could also be the Recipient Network or a Serving Network, in which case routeing functions as described in the relevant subclauses below should be carried out. If non geographic numbers are allocated by the NPA to users instead of Service Providers, the originating network may (also) be a serving network, or have a transit network acting as a serving network on its behalf. Otherwise, the Range Analysis Function should be carried out to route the call towards a Serving Network, possibly via a Transit Network. Transit Network The Transit Network should carry the call between two other networks. The Transit Network may or may not be acting as a Serving Network; if it is, it should carry out functions as described in the Serving Network section. If it is not, the Transit Network should: - if a routeing number has previously been added by another network, carry out the Range Analysis Function on this routeing number to route the call towards the Recipient Network (possibly via another Transit Network); - if no routeing number has been previously added, carry out the Range Analysis Function on the called party number to route the call towards a Serving Network (possibly via another Transit Network). 19 TR 101 119 V1.1.1 (1997-11) Donor Network A donor network is only involved in NGNP if the NPA assigns number ranges to particular Service Providers, hence networks. In these cases the donor network can act as the serving network. Recipient Network The Recipient Network should use either the routeing number or the non geographic number to execute the service logic function and thus provide the customer service. As an option the number translation function is not carried out by the recipient network, rather it is carried out by the serving network based on information received from the recipient network Serving Network The Serving Network should carry out functionality as follows: - the Call Trap Function should be carried out to determine that a number may be ported; - the Database Query Function should be carried out to determine a routeing number; - the Routeing Number addition function is carried out; - the Range Analysis Function should be carried out on the routeing number to direct the call towards the Recipient Network (possibly via a transit network). The serving network functionality may be split across various networks. |
94cc37b251e47c47264903912f7a4868 | 101 119 | 7.3.2 Service Provider Responsibilities | In this subclause the responsibilities related to service provision and number management are described. Donor Service Provider The donor Service Provider should not reallocate ported numbers to another customer. When evolution changes in the number plan affects a ported number, the effects should be specified in the interconnect agreement. Recipient Service Provider When evolution changes in the number plan affects a ported number, a migration path needs to be agreed with the entities involved. The entities involved depends upon the specific implementation. The recipient Service Provider will inform the donor Service Provider of a change of circumstances that may affect calls being delivered to a ported number. A recipient Service Provider will ensure that a customer should not experience any limitations in the service offered by an operator whether his/her number is ported or not. While the exact nature of the service offered to a ported customer is a commercial matter to be decided upon by the recipient operator, if the recipient operator offers a similar service to customers who have not ported their number, then they should have the ability to offer the same functionality, irrespective of whether the number has been ported or not, if the Service Provider wishes. Customers will get access to the services determined by the Service Provider to whom they are connected, irrespective of whether their number has been ported or not. |
94cc37b251e47c47264903912f7a4868 | 101 119 | 8 Number portability for ETNS services | The new emerging market developments and the Commission of the European Union (CEU) are determining new requirements on the numbering of telecommunication services. One of the most important requirements is the creation (in parallel to the present national numbering plans) of ETNS to provide ETNS services. The ETNS is planned to be implemented by using an additional country code (388) reserved for ETNS services. The European Number (EN) is not directly usable to get the physical location of the called party. 20 TR 101 119 V1.1.1 (1997-11) When an ETNS call is set up usually two number translations are required. The ETNS call is routed to the concerned ETNS Translation database where the EN is translated into a Routeing number which contains the identity of the next translation database. The second translation is made by a Service Provider Translation database before the call reaches its final destination. When the European number is ported from the donor Service Provider to the recipient Service Provider a change of Service Provider implies a new Routeing number. Therefore the changing of Service Providers impacts on the Routeing number associated to the EN. As such portability of Pan European Numbers is a special case of NGNP, where the routeing number is internationally significant. The portability of European numbers impacts on the management of the ETNS resource. In particular the Registrar that is responsible for the handling of the Subscriber Number plays an important role in the management of the ported European numbers. The Registrar should keep track of the status of the European Numbers allocated to the various Service Providers and then document whether a number has been ported or not. From the management point of view when an EN number is ported from the donor Service Provider to the recipient Service Provider some actions take place between the two Service Providers and the Registrar. These actions can be summarized in three steps: 1) the Recipient SP has the responsibility to inform the Registrar that he has acquired a new customer with a ported EN; 2) the Registrar should keep track that the EN indicated by the Recipient Service Provider is now a EN ported number from the donor Service Provider to the recipient Service Provider ; 3) the Registrar should de-allocate the ported EN from the Donor Service Provider. The interactions above described between the SPs and the Registrar may take a certain amount of time especially in the first phase where these interactions will not be fully automatic. The use of non-automatic interactions based on the involvement of human operators may affect in a negative way the quality of the service offered to the customers of ETNS services. For example when the customer moves from SP A to SP B it is possible to have a period of time where the service is not available due to the allocation/de-allocation procedures of the ported European number. Two possibilities exist for the distribution of the routeing numbers to the ETNS Translation Database. The first possibility is the Service Provider informs the Registrar of the Routeing Number associated to the EN. The Registrar is responsible to distribute this information to the relevant ETNS translation database(s); this is the centralized approach. The second possibility is that the Service Provider has the responsibility to distribute the Routeing Number associated to the EN to the relevant ETNS Translation Database(s); this is the distributed approach. The location and the number of the ETNS Translation databases for a specific pan-European service depends on the Routeing methodology chosen to route the ETNS call. The alternatives vary from one single ETNS Translation database to a number of ETNS Translation databases (one in each European network from where an ETNS call is originated). 21 TR 101 119 V1.1.1 (1997-11) |
94cc37b251e47c47264903912f7a4868 | 101 119 | 9 Impact on other services | Number Portability shall not inhibit support of PSTN and ISDN services. This ideally includes the TC based services, e.g. CCBS and MW. |
94cc37b251e47c47264903912f7a4868 | 101 119 | 10 Quality of Service | The object of this clause is to specify the quality of service encountered by the user. When a number is ported, additional times are incurred that may degrade performance. Two elements combine to create the additional time; these are the ‘look up time’ and ‘subsequent connect time’. The interconnect agreement needs to: - apportion the times for these delays to each of the operators involved; - specify from when the timings start. In discussing the apportionment of the timings to the operators care needs to be taken which operator performs which function. Also the interconnect agreement needs to take account of the legacy systems available, recognizing that existing technology should not be a barrier to implementing Number Portability. The goal of any interconnect agreement should be to ensure that the combined additional delay should not exceed 1 second. Where this can not be currently met, then plans should be made to improve the existing times associated with the Service Providers such that the Post Dial Delay to a ported number should be no more than 1 second compared to a call to a non ported number. Incoming calls to a ported number should not suffer undue loss of quality of service. ETSI can play an important role in addressing these quality of service issues, by discussing the issues that arise, and by contributing to the European Interconnect Forum (EIF), which is taking the European lead on this issue. 22 TR 101 119 V1.1.1 (1997-11) History Document history V1.1.1 November 1997 Publication ISBN 2-7437-1817-X Dépôt légal : Novembre 1997 |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 1 Scope | The present document gives background information on the performance of the GSM enhanced full rate speech codec. Experimental results from the Pre-selection and Verification tests carried out during the standardization process by the SEG (Speech Expert Group) are reported to give a more detailed picture of the behaviour of the GSM enhanced full rate speech codec under different conditions of operation. |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 2 References | The following documents contain provisions which, through reference in this text, constitute provisions of the present document. • References are either specific (identified by date of publication, edition number, version number, etc.) or non-specific. • For a specific reference, subsequent revisions do not apply. • For a non-specific reference, the latest version applies. • A non-specific reference to an ETS shall also be taken to refer to later versions published as an EN with the same number. • For this Release 1999 document, references to GSM documents are for Release 1999 versions (version 8.x.y). [1] GSM 03.05: "Digital cellular telecommunications system (Phase 2+); Technical performance objectives". [2] GSM 03.50: "Digital cellular telecommunications system (Phase 2+); Transmission planning aspects of the speech service in the GSM Public Land Mobile Network (PLMN) system". [3] GSM 06.08: "Digital cellular telecommunications system (Phase 2+); Half rate speech; Performance of the GSM half rate speech codec". [4] GSM 06.10: "Digital cellular telecommunications system (Phase 2+); Full rate speech transcoding". [5] GSM 06.20: "Digital cellular telecommunications system (Phase 2+); Half rate speech transcoding". |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 3 Abbreviations | For the purposes of the present document, the following abbreviations apply: A/D Analogue to Digital ADPCM Adaptive Differential Pulse Code Modulation ACR Absolute Category Rating BSC Base Station Controller BTS Base Transceiver Station C/I Carrier-to-Interferer ratio CI Confidence Interval CNI Comfort Noise Insertion CRC Cyclic Redundancy Check D/A Digital to Analogue DAT Digital Audio Tape DCR Degradation Category Rating DSP Digital Signal Processor DTMF Dual Tone Multi Frequency DTX Discontinuous Transmission for power consumption and interference reduction EFR Enhanced Full Rate ETSI ETSI TR 101 085 V8.0.0 (2000-06) 9 (GSM 06.55 version 8.0.0 Release 1999) ESP Product of E (Efficiency), S (Speed) and P (Percentage of Power) of the DSP FR Full Rate GBER Average gross bit error rate GSM Global System for Mobile communications HR Half Rate IRS Intermediate Reference System, No IRS= rather flat ITU-T International Telecommunication Union – Telecommunications Standardization Sector MNRU Modulated Noise Reference Unit Mod. IRS Modified IRS MOPS Million of Operation per Seconds MOS Mean Opinion Score MS Mobile Station MSC Mobile Switching Centre PCM Pulse Code Modulation PSTN Public Switched Telecommunications Network Q Speech-to-speech correlated noise power ratio in dB SD Standard Deviation SEG Speech Expert Group SID Silence Descriptor SMG Special Mobile Group TCH-EFS Traffic Channel Enhanced Full rate Speech TCH-FS Traffic Channel Full rate Speech TCH-HS Traffic Channel Half rate Speech TDMA Time Division Multiple Access TMOPS True Million of Operation per Seconds UPCM Uniform or Linear PCM VAD Voice Activity Detector WMOPS Weighted Million of Operations per Seconds Four different Error Patterns (EP0, EP1, EP2 and EP3) were used, where: EP0 without channel errors EP1 C/I=10 dB; 5% GBER (well inside a cell) EP2 C/I= 7 dB; 8% GBER (at a cell boundary) EP3 C/I= 4 dB; 13% GBER (outside a cell) 4 Quality under error (EP0 – EP3) and tandeming conditions (Exp Number 1 and Exp Number 5) A listening-only test was adopted using the Absolute Category Rating (ACR) method. The results are reported in terms of Equivalent Q (dB) values and Differential Q values (which compare the codec results to the High and Low references). For error and tandeming conditions, results are available from eight laboratories (lab1 to lab8). Tables of results on a lab-by-lab basis are shown in the annex of the present document (table A.1.1 to table A.1.8), negative values indicating worse performance than the reference. In general, across all laboratories, the EFR codec performs better than the reference TCH-FS for clear speech (EP0), for error conditions EP1 and EP2 and for tandeming under error EP1 conditions. For severe error condition (EP3), the performance is worse than TCH-FS in one laboratory. The EFR is equivalent to the reference G.728 (high reference) for clear speech in all laboratories. Under error conditions, the high reference threshold for severe error condition (EP3) is not met in all laboratories while the threshold for EP1 and EP2 is met for, roughly, half of the laboratories. Under tandeming, the clear condition was tested in only one laboratory where it was compared to another standard G.721; the results indicate that the performance of the EFR (EP0 tandem) is equivalent to that of G.721 (EP0). For tandeming under error condition EP1, equivalence with TCH-FS (EP1) without tandeming is demonstrated in all laboratories except one. Additional results coming from one lab only can be found in table A.1.6 (effect of input levels, other error conditions, tandeming with other standards). The advantage of the EFR compared to the actual TCH-FS is not independent of the quality of the network. As channel errors increase, this advantage is reduced. The general trend of the EFR behaviour in error conditions is shown in figure 15. ETSI ETSI TR 101 085 V8.0.0 (2000-06) 10 (GSM 06.55 version 8.0.0 Release 1999) 5 Quality under background noise conditions (Exp Number 2 and Exp Number 3) This was assessed with a listening-only test, using the Degradation Category Rating (DCR) method. The results are reported for the EFR codec, the Reference G.728 and the TCH-FS codec in terms of DMOS values with Confidence Interval (CI). Six laboratories (lab1 to lab4, lab6 and lab7) performed this experiment, the first four complying with SEG-4 (see table A.2.1 and table A.2.2). For each laboratory, the differences in DMOS scores between the EFR codec and the Reference G.728 are of the same order as the confidence intervals for the EFR codec results, with the exception of one point (vehicle noise) in one laboratory. From this, it can be concluded that the performance of the EFR codec, under the background noise conditions tested is equivalent to that of the quality reference G.728 for all laboratories and also to G.721 (tested in one lab only). The degradation introduced by the EFR codec compared to the DIRECT connection in background noise conditions is rated between "unnoticeable" and "noticeable but not annoying". A substantial improvement is achieved over the full rate with music in the background. Additional results from one laboratory can be found in table A.2.2. |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 6 Talker dependency (Exp Number 4) | A listening-only test was used with the Degradation Category Rating (DCR) methodology. Results, available from five laboratories (lab1 to lab4 and lab7), are reported in terms of DMOS values with their associated Standard Deviation (SD) to give a measure of the spread of the scores about the averages for each gender for both the EFR codec and the Reference G.728. These experiments clearly show that the standard deviation of the scores of EFR codec for each gender is smaller than the standard deviation of the reference G.728 in each laboratory. The talker dependency performance for the EFR codec is therefore equivalent to that of G.728. Also, the gender dependency is equivalent to that of the G.728 codec. Tables of results lab-by-lab are shown in the annex (table A.3.1 to table A.3.2). |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 7 DTX system | |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 7.1 Channel activity in DTX mode | |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 7.1.1 Test procedure | A carefully selected subset of the speech material recorded for testing the half rate DTX system was processed through the codec/DTX C-language simulation. This material comprised 48 real conversations in the English, German and Italian languages. The channel activity of the system was measured for all 48 conversations, and the mean channel activity was then calculated. |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 7.1.2 Speech channel activity | The percentage of speech frames scheduled for transmission by the radio subsystem (subsequently referred to as the speech channel activity) varied significantly between conversations. Speech channel activities ranged from 29% to 93% for individual sides of a conversation. For this reason, it was not possible to identify any significant trends in the results with regard to terminal type and environmental conditions. The mean speech channel activity, measured over all 48 conversations, was 61 %. |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 7.1.3 Level compensation | After calculating the mean speech channel activity, it was found that the speech material had been processed at a level 6,5 dB below the original recorded level. However, the activity of the basic VAD algorithm rises approximately 0,5 per cent per dB increase in input level. To compensate for this, a factor of 3 % must be added to the speech channel activity estimate. ETSI ETSI TR 101 085 V8.0.0 (2000-06) 11 (GSM 06.55 version 8.0.0 Release 1999) |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 7.1.4 Interleaving compensation | The channel activity measurements were calculated on a signal frame basis. However, the use of interleaving (depth 4) implies that the TDMA activity will be approximately 2 % higher than the signal frame activity. |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 7.1.5 Estimated mean TDMA channel activity | The estimated mean TDMA channel activity is shown in table 7.1.5.1. Table 7.1.5.1: Calculation of mean TDMA channel activity speech channel activity 61 % level compensation 3 % interleaving compensation 2 % total TDMA channel activity 66 % |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 7.2 DTX/CNI Informal Expert Listening tests | |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 7.2.1 Introduction | To check the performance of the DTX / CNI system of the ETSI GSM EFR codec, informal expert listening tests were done in Italian and German language. Also a very brief check of English speech samples was done. Special attention was given to clipping effects and noise. |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 7.2.2 Test environment | Out of the speech samples from the HR codec DTX tests, 8 conversations were selected by CSELT, Deutsche Telekom and British Telecom, respectively. These samples were processed by Nokia and recorded on a DAT, one track without VAD/DTX processing and one track with the DTX / CNI system. By comparing the non-DTX and DTX speech, the listeners could judge the degradation to be not noticeable, minor, moderate or severe. It was allowed to rewind the tape to repeat listening to critical sections. The listening device was a high quality head set in mono operation to have either track 0 or track 1 signal on both speakers. |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 7.2.3 Results | In all the speech samples, only two clippings were judged to be noticeable. On comfort noise insertion, conversations with almost no or low background noise were found to have no noticeable degradation. With increasing background noise, the noise related degradation was judged from minor to moderate (the latter in two sections of two conversations). The overall performance of the DTX / CNI system was seen to be fully satisfactory with mostly no or minor degradation. |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 8 Performance with DTMF tones | |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 8.1 Introduction | A desirable requirement for the GSM Enhanced Full Rate speech codec is a DTMF transparency not worse than the GSM Full Rate codec. For the verification of the ETSI Enhanced Full Rate codec, the DTMF transmission was tested. ETSI ETSI TR 101 085 V8.0.0 (2000-06) 12 (GSM 06.55 version 8.0.0 Release 1999) |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 8.2 Test environment | A DSP (NEC µPD77016) based PC board was used to measure the transmission of the codec under test. The DTMF software is derived from the Goertzel algorithm which allows to calculate the spectral powers of distinctive frequencies by means of a recursive digital filter scheme. The DTMF signal detection is based on "quality factors" calculated from the Distinctive Frequency Test results. Within a wide dynamic range this technique is independent from an absolute signal level. Based on the same hardware and software, PTT approvals are available with equipment of European Telecom houses. DTMF signals were tested only under ideal transmission conditions. Error patterns like in the half rate case were not simulated. In the different experiments the input signals were modified in tone and pause length, amplitude (also introducing twist, i.e. different amplitude in the two components of the tone) and frequency. In all experiments 10 tones were input to the codec. The resulting files were processed by the DTMF detector. As the minimum tone length specified for an input signal of a detector is 80 ms while the minimum output length of a DTMF generator may be smaller, a test was also done with a 60 ms tone to the codec. |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 8.3 Results | The test results shown in table 8.3.1 represent the detected tones from the 10 input signals. Table 8.3.2 summarises the test conditions. With input signals fully in the specified range no detection problems were observed. The shortest allowed input signal to a transmission line (80 ms) was detected 100 % in all experiments with different input levels, twist and frequency deviations. A strange effect known from the HR codec tests with long tones detected as two tones was not observed. Only in case of tones shorter than 80 ms the detection rate was down to 96 %, without a sharp decrease and without a distinct tone showing problems. As a conclusion, the codec is tested to be 100 % transparent to DTMF signals under nominal conditions. Only tones shorter than minimum input specifications of 80 ms are not fully detected. The results are better compared to the FR codec. The requirement is fulfilled. Table 8.3.1: Results of DTMF experiments experiment tone N18 N22 N18-22 N22-26 D18 D18-22 L 120 L 200 S 60 1 10 10 10 10 10 10 10 10 10 2 10 10 10 10 10 10 10 10 9 3 10 10 10 10 10 10 10 10 10 4 10 10 10 10 10 10 10 10 9 5 10 10 10 10 10 10 10 10 10 6 10 10 10 10 10 10 10 10 10 7 10 10 10 10 10 10 10 10 10 8 10 10 10 10 10 10 10 10 10 9 10 10 10 10 10 10 10 10 10 0 10 10 10 10 10 10 10 10 10 * 10 10 10 10 10 10 10 10 10 # 10 10 10 10 10 10 10 10 9 A 10 10 10 10 10 10 10 10 10 B 10 10 10 10 10 10 10 10 9 C 10 10 10 10 10 10 10 10 9 D 10 10 10 10 10 10 10 10 10 total_d 160 160 160 160 160 160 160 160 155 det_rate 100 100 100 100 100 100 100 100 96 In rows 1 – D the number of detected tones from 10 inputs is shown ETSI ETSI TR 101 085 V8.0.0 (2000-06) 13 (GSM 06.55 version 8.0.0 Release 1999) Table 8.3.2: Conditions of above listed experiments experiment N18 N22 N18-22 N22-26 D18 D18-22 L 120 L 200 S 60 tone 80 80 80 80 80 80 120 200 60 ms pause 80 80 80 80 80 80 120 80 60 ms r_amp -18 -22 -18 -22 -22 -18 -22 -28 -22 dB c_amp -18 -22 -22 -26 -22 -22 -22 -28 -22 dB delta_f 0 0 0 0 2 2 0 0 0 % r_amp and c_amp are the row amplitude and column amplitude respectively, dB values are relative to the overload point. |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 9 Network information tones | The signals shown in table 9 were first compressed by the encoder, then decompressed by the decoder, and then listened to via quality headphones using a high-quality PC audio card. The codec showed no perceivable degradation to the transmission of these PSTN network information tones both with and without the VAD/DTX system switched on. No clipping or other disturbing artefacts were noticed when DTX was enabled. Checking tones in use around the world as listed in ITU Recommendation E.180 Supplement 2 (Jan 94) indicated that this test achieves almost 100 % global coverage by simply testing UK, German, and USA tones. Table 9: PSTN Information Tones Tested German (no DTX) German (with DTX) 3 dial tones 2 dial 1 ringing tone 1 ringing 2 busy tones (subscriber engaged) 2 busy 1 special information tone (number unobtainable) 1 special information tone 2 congestion tones (network equipment engaged) 1 fax modem call setup tone sequence United Kingdom (no DTX) United Kingdom (with DTX) 3 dial tones 1 dial 1 ringing tone 1 ring 1 busy tone (subscriber engaged) 1 busy 1 congestion tone (network equipment engaged) 1 congest - 1 sustained, low-level sinusoid (number unobtainable) USA (no DTX) USA (with DTX … not tested) 1 dial tone - 1 ringing tone - 1 busy tone (subscriber engaged) - 1 special information tone - 1 congestion tone (network equipment engaged) - Tones were computer generated for the tests in which DTX was switched off. Authentic DAT recordings of PSTN information tones were used to check the performance with DTX switched on, except the low-level sinusoid signal for "UK number unobtainable" which was computer generated. |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 10 Performance with special input signals | Two kinds of special input signals have been chosen to be tested in the verification phase of the Enhanced Full Rate: music signals and noise signals. |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 10.1 Music signals | This subclause reports on the informal listening tests conducted in CSELT to evaluate the performance of the EFR codec with music signals. ETSI ETSI TR 101 085 V8.0.0 (2000-06) 14 (GSM 06.55 version 8.0.0 Release 1999) The tests have been based on informal pair comparison tests (A versus B without repetition) by considering the Full-rate codec, the Enhanced Full-Rate as well as the ITU-T ADPCM G.726 codec at 32 kbit/s. The tests involved 6 music items taken from those selected by ISO-MPEG to test audio codec standards. The duration of the different music items lasts in the range between 8 and 10 seconds. Music items have been downsampled to 8 kHz before processing. Listening was performed by 12 naive listeners through headphones. The results are reported in tables 10.1.1 and 10.1.2. Table 10.1.1: Results of the informal test on performance with music signals: Enhanced Full Rate versus Full Rate Music Items Enhanced Full Rate preferred to Full Rate Enhanced Full Rate equal to Full Rate Full Rate preferred to Enhanced Full Rate Harpsichord 100 % 0 % 0 % Carmen 25 % 41,7 % 33,3 % Trumpet 100 % 0 % 0 % Castanets 33,3 % 41,7 % 25 % Mediterraneo 41,7 % 33.3 % 25 % Vivaldi "The spring" 100 % 0 % 0 % Total 66,7 % 19,4 % 13,9 % Table 10.1.2: Results of the informal test on performance with music signals: Enhanced Full Rate versus ADPCM 32 kbit/s Music Items Enhanced Full Rate preferred to ADPCM Enhanced Full Rate equal to ADPCM ADPCM preferred to Enhanced Full Rate Harpsichord 50 % 8,3 % 41,7 % Carmen 0 % 25 % 75 % Trumpet 33,3 % 33,3 % 33,3 % Castanets 8,3 % 41,7 % 50 % Mediterraneo 16,7 % 25 % 58,3 % Vivaldi "The spring" 16,7 % 25 % 58,3 % Total 20,9 % 26,4 % 52,7 % The analysis of results shows a certain dependency of performance on the music item. There is at least one item in which the FR has been judged better than the EFR. Nevertheless, on the average, the EFR provides better performance than the FR, whilst it appears to perform worse than the ADPCM. |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 10.2 Noise signals | To check the scaling performance of the fixed point algorithm a noise signal with levels ranging from -10 dB down to -70 dB have been processed by encoder and decoder in error free conditions. The level of the decoder output signal was examined. It was found that for all signals the reconstructed output level followed the input level. Even for very low signal levels no problems were detected. |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 11 Performance with different languages | This clause deals with the results of an informal listening test to evaluate the performance of the EFR for some languages which were not tested formally. The tests have been based on informal pair comparison (A versus B without repetition) by considering the Full-rate codec, the Enhanced Full-Rate as well as the ITU-T ADPCM G.726 codec at 32 kbit/s. The tests involved 5 different languages (Arab, Chinese, Japanese, Polish and Portuguese). Listening and recording was performed by naive, mother tongue people. For most languages, however, it was possible to use only one listener thus suggesting to take the results with the due caution. The test was performed by collecting people of different mother-tongue at CSELT premises. Subjects were asked to record a list of sentences in their own languages. The sentence length was in the range from 4 to 6 seconds. The list of languages, number of listeners and samples is reported in table 11.1. ETSI ETSI TR 101 085 V8.0.0 (2000-06) 15 (GSM 06.55 version 8.0.0 Release 1999) Table 11.1: List of languages and the number of listeners and sentences used LANGUAGE NUMBER OF LISTENERS NUMBER OF SENTENCES Arab 2 8 Chinese 1 8 Japanese 1 8 Polish 2 8 Portuguese 1 8 The subject were asked to listen to an A-B sequence and allowed to express a preference as well as to judge the perceived quality to be the same. The results of the test are reported in tables 11.2 and 11.3. Table 11.2: Results of the informal test on languages not covered in the formal tests: Enhanced Full Rate versus Full Rate Languages Enhanced Full Rate preferred to Full Rate Enhanced Full Rate equal to Full Rate Full Rate preferred to Enhanced Full Rate Arab 37,5 % 50 % 12,5 % Chinese 100 % 0 % 0 % Japanese 100 % 0 % 0 % Polish 68,7 % 12,5 % 18,8 % Portuguese 75 % 25 % 0 % Table 11.3: Results of the informal test on languages not covered in the formal tests: Enhanced Full Rate versus ADPCM at 32 kbit/s Languages Enhanced Full Rate preferred to ADPCM Enhanced Full Rate equal to ADPCM ADPCM preferred to Enhanced Full Rate Arab 18,75 % 75 % 6,25 % Chinese 87,5 % 12,5 % 0 % Japanese 87,5 % 12,5 % 0 % Polish 25 % 37,5 % 37,5 % Portuguese 12,5 % 50 % 37,5 % The analysis of the results confirms the good performance of the Enhanced full-rate also for languages not considered in the formal experiments. This seems to be the case for all the languages tested, even though the test size was very small. The EFR was always preferred in comparison to the Full-rate. For Chinese and Japanese the preference is stronger and, for these languages, the EFR is preferred also to the ADPCM at 32 kbit/s in most of the cases. |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 12 Delay | The round-trip delay of a communication using a TCH-EFS has been estimated taking into account all the system and processing delays. The symbol definitions for the calculations in this section are: Tabisd The time required to transmit the 260 speech frame data bits (bits D1 – D260, C16 and the 17 synchronization bits -> 278 bits) over the 16 kbit/s A-bis-interface in the downlink direction (system dependent). Tabisu The time required to transmit the first 137 TRAU frame bits, the first 34 of which can be sent by anticicipation, leading to a delay of 103 TRAU frame bits (D2 – D98 speech frame data bits including the CRCs + 6 synchronization bits) over the 16 kbit/s A-bis-interface in the uplink direction (system dependent). Tad Delay in the analogue to digital converter in the uplink. Tbsc Switching delay in the BSC (implementation dependent). ETSI ETSI TR 101 085 V8.0.0 (2000-06) 16 (GSM 06.55 version 8.0.0 Release 1999) Tbuff Due to the time alignment procedure for inband control of the remote transcoder in case of a 16 kbit/s A-bis-interface in the downlink direction, it is required to have a buffer in the BTS of 1 ms + one 250 s regulation step (system dependent). Tda Delay in the digital to analogue converter in the downlink. Techo Delay due to the echo canceller. Tencode: The time required for the channel encoder to perform channel encoding (implementation dependent). Tmsc Switching delay in the MSC. Tpcm The duration of a segment of PCM speech for the downlink processing delay. Tproc: The time required after reception of the last encoded speech parameter of the first subframe (FCB-Gain1) to process the speech encoded data for the enhanced full rate speech decoder and to produce the first PCM output sample (implementation dependent). Trftx: The time required for transmission of a TCH radio interface frame over the air interface due to the interleaving and de-interleaving (system dependent). Trxproc: The time required after reception over the radio interface to perform equalization, channel decoding and SID-frame detection (implementation dependent). Tsample: The duration of the segment of PCM speech operated on by the speech transcoder. Tsps Delay of the speech encoder in the BSC after reception of the last PCM sample until availability of the first encoded bit (implementation dependent). Ttransc: The MS speech encoder processing time, from input of the last PCM sample to output of the final encoded bit (implementation dependent). The processing delays were estimated from the detailed complexity figure that has been previously computed in the verification phase. The complexity estimation is based on rules that are supposed to be relevant from an implementation point of view and independent from specific DSPs at the same time. Therefore it was tried to follow the same philosophy for the processing delays. The DSP that runs the codec has been modelled through three parameters E, S and P. E stands for the Efficiency of the DSP. This corresponds to the ratio TMOPS/WMOPS of the implementation of the codec on the DSP. S stands for the Speed of the DSP: Maximum Number of Operations that the DSP can run in 1 second. This number is expressed in MOPS. P stands for the percentage of DSP processing power assigned to the codec. The processing delay of a task whose complexity is X can then be computed using the formula: D = X*20/ESP, the time unit being ms. The following assumptions were made when computing the round-trip delay: - for the enhanced Full Rate MS delay, it is assumed that the DSP has the same performance as the DSP used for GSM HR [5]; - for the Enhanced Full Rate BSC delays, it is assumed that the DSP of the TRAU will have the same performance as the DSP used for GSM HR; - for the Enhanced Full Rate BTS delay, it is assumed that the DSP will have the same performance as the DSP used for GSM FR [4]. The reason is that it is assumed that the GSM Full Rate BTS will be reused during first GSM EFR deployments; - a 16 kbit/s submultiplexed A-bis is used between the BTS and the BSC-TRAU. ETSI ETSI TR 101 085 V8.0.0 (2000-06) 17 (GSM 06.55 version 8.0.0 Release 1999) From these assumptions and following the complexity of GSM HR [3] and its delay requirement for the MS [2], the ESP value has been computed for EFR: ESP = 25 The following list of delays provided in [1] and [2] for the GSM Full Rate and common to the GSM Enhanced Full rate are considered realistic and therefore retain the same value: - MSC Tmsc margin - BSC Tbsc margin - BTS Trxproc margin - MS Trftx Tda The results of the estimation are provided in table 12.1 for uplink and table 12.2 for downlink. The time unit for all delays is ms (10-3 s). Table 12.1: Uplink delay Equipment Speed Parameter Delay (ms) Data MSC Tmsc 0,5 margin 0,5 BSC Tbsc 0,5 Tproc 1,27 1,59 WMOPS margin 0,5 BTS Tabisu 6,4375 103 bits Trxproc 8,8 2,45 WMOPS (note) margin 3 MS Trftx 37,5 Tencode 0,32 0,20 WMOPS Ttransc 12,17 15,21 WMOPS Tsample 20 Tmargin 2 Tad 1 SUM Uplink 94,4975 NOTE: This theoretical complexity corresponds to the channel decoding only. This leaves 6,84 ms for the equaliser in Trxproc. ETSI ETSI TR 101 085 V8.0.0 (2000-06) 18 (GSM 06.55 version 8.0.0 Release 1999) Table 12.2: Downlink delay Equipment Speed Parameter Delay (ms) Data MSC Techo 1 Tmsc 0,5 margin 0,5 BSC Tbsc 0,5 Tsample 20 Tsps 2,3 Tabisd 17,375 278 bits margin 0,5 BTS Tbuff 1,25 Tencode 1,60 0,20 WMOPS margin 0,45 MS Trftx 37,5 Trxproc 8,8 2,45 WMOPS (note) Tproc 1,27 1,59 WMOPS margin 2 Tda 1 SUM Downlink 96,547 NOTE: This theoretical complexity corresponds to the channel decoding only. This leaves 6,84 ms for the equaliser in Trxproc. Round-trip delay = Uplink delay + Downlink delay = 191,04 ms This delay is very close to the delay indicated in [1], [2] and [3] for GSM Full Rate: 188,5 ms. The difference should be unnoticeable. |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 13 Frequency response | |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 13.1 Introduction | A characteristic test in the verification of GSM speech codecs is the frequency response test. Sine tones in the telephony frequency band are input to the codecs, and after decoding the gain is calculated. It has to be pointed out that the frequency response measurement is given just as a piece of additional information and does not add information on the actual behaviour of the codec in terms of perceived quality or DTMF transparency. |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 13.2 Test environment | The tones were calculated to a nominal level of 22 dB below the overload point. Tones ranging from 80 Hz to 3 600 Hz in steps of 21 Hz with a nominal length of 2 s were input to the codec under test. After decoding the gain was calculated with averaged results of 400 ms intervals and again averaged for the total duration of one frequency to get the frequency response curve. This was done to check the transition behaviour of the codec and eventually disregard the first samples. |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 13.3 Results | Within the telephony band the frequency response is very flat. No abnormal deviations were observed. Also additional experiments with different input level (-18 dB, -28 dB), or different tone length (500 ms, 4 s) resulted in almost identical curves. The decreasing gain above 3 kHz is relative small and far away from a 3 dB margin. The transition behaviour was very good. ETSI ETSI TR 101 085 V8.0.0 (2000-06) 19 (GSM 06.55 version 8.0.0 Release 1999) -9 -6 -3 0 3 100 1000 10000 f [Hz] ain [dB] L -22dB L -28dB Figure 13: GSM EFR codec frequency response at different input levels |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 14 Complexity | The complexity of the Enhanced Full Rate is characterised by the 3 following items: - the number of cycles; - the data memory size; - the program memory size. The values of these different figures depend on a specific DSP implementation. Nevertheless, the results obtained by the C description analysis can be used as references. The speech transcoding functions are specified using a set of basic arithmetic operations. The WMOPS figure quoted is a weighted sum of the operations required to perform transcoding. The weight assigned to each operation is representative of the number of instruction cycles required to perform that operation on a typical DSP device. The complexity range of the Enhanced Full Rate is equivalent to the Half Rate codec complexity. The number of cycles required by the Enhanced Full Rate algorithm is relatively independent on the values of the input samples. The execution time of an average and an extreme input case are equivalent. Nevertheless the following table presents the theoretical worst case evaluation, i.e. the maximum possible number of cycles, which is consistent with the results indicated in [3]. The following figures are associated to the Speech and Channel part excluding the DTX functions. Table 14: Principal complexity figure Theoretical worst case WMOPS Data RAM (note) (16 bits words) Data ROM (constants) (16 bits words) Program ROM (assembly instructions) Enhanced Full Rate 18,1 4 708 5 363 6 000 – 9 000 Half Rate 21,2 5 002 8 781 8 000 – 12 000 NOTE: The Data RAM figure can be split in 2 parts: the static variables: 2 240 words; and the dynamic variables (i.e. local to a procedure ): 2 468 words. ETSI ETSI TR 101 085 V8.0.0 (2000-06) 20 (GSM 06.55 version 8.0.0 Release 1999) |
43a1c5253102ebd5abf64ff5655e1f8d | 101 085 | 15 Summary of the results from the subjective testing | The EFR codec is better than the actual FR codec for clear speech, for all error conditions (EP1, EP2 and EP3) and for tandeming under error EP1; it is equivalent to G.728 for its intrinsic quality, for background noise conditions and talker dependency. The EFR codec does not reach the objective performance target (TCH-FS EP2) for severe error condition EP3; for error conditions EP1 and EP2 it does not reach the objective performance target for half of the results. The EFR quality under tandeming condition without error was not tested against the target G.728 but is found equivalent to G.721. The advantage of the EFR compared to the TCH-FS is dependant of the quality of the network. As channel errors increase, this advantage is reduced. Table 15: Summary of Results Conditions High Ref Low Ref EP0 Equivalent to G.728 Equivalent to G.728 Better than TCH-FS EP1 Worse than MNRU 24 dB for half of labs Better than TCH-FS (EP1) EP2 Worse than TCH-FS (EP1) for half of labs Better than TCH-FS (EP2) EP3 Worse than TCH-FS (EP2) Better than TCH-FS (EP3) except for one lab. EP0 (tandem) G.728 (not tested) Equivalent to G.721 G.728 (not tested) Equivalent to G.721 EP1 (tandem) Equivalent to TCH-FS (EP1) Better than TCH-FS (EP1 tandem) Vehicle 10 Equivalent to G.728 Equivalent to G.728 Music 20 Equivalent to G.728 Equivalent to G.728 Better than TCH-FS Male Talkers Equivalent to G.728 Equivalent to G.728 Female Talkers Equivalent to G.728 Equivalent to G.728 Children Equivalent to G.728 Equivalent to G.728 ETSI ETSI TR 101 085 V8.0.0 (2000-06) 21 (GSM 06.55 version 8.0.0 Release 1999) Tendency of subjective listening tests Error rate vs. speech quality without background noise GSM FR G.728 (reference) GSM EFR Error rate zero moderate high very high Figure 15: General trend of the EFR behaviour for error conditions in noise-free environment ETSI ETSI TR 101 085 V8.0.0 (2000-06) 22 (GSM 06.55 version 8.0.0 Release 1999) Annex A: Summary of results (lab by lab) A.1 Quality under Error and tandeming conditions Table A.1.1: Q values and Differential Q (dB) values from References for error and tandeming conditions (BT/lab1, Mod. IRS input characteristics – SEG-4, Exp#1 and Exp#5) Conditions Differential Q Values (High Ref) Differential Q Values (Low Ref) Q Values EFR Q Values High Ref. Q Values Low Ref. EP0 +3,71 +3,71 29,86 26,15 26,15 EP1 -2,42 +2,96 21,58 24 18,62 EP2 -2,97 +0,96 15,65 18,62 14,69 EP3 -11,30 -0,55 0,41 11,71 0,96 EP0 (tandem) - - - 22,94 22,94 EP1 (tandem) --2,72 +1,26 15,90 18,62 14,64 Table A.1.2: Q values and Differential Q (dB) values from References for error and tandeming conditions (CNET/lab2, Mod. IRS input characteristics – SEG-4, Exp#1 and Exp#5) Conditions Differential Q Values (High Ref) Differential Q Values (Low Ref) Q Values EFR Q Values High Ref. Q Values Low Ref. EP0 +12,59 +12,59 39,06 26,47 26,47 EP1 0 / -1,33 +6,14 22,67 22,67 / 24 16,53 EP2 +0,15 +2,32 16,68 16,53 14,36 EP3 -11,95 +1,21 2,41 14,36 1,20 EP0 (tandem) - - - 25,71 25,71 EP1 (tandem) +2,22 +5,29 18,75 16,53 13,46 Table A.1.3: Q values and Differential Q (dB) values from References for error and tandeming conditions (TD/lab3, Mod. IRS input characteristics – SEG-4, Exp#1 and Exp#5) Conditions Differential Q Values (High Ref) Differential Q Values (Low Ref) Q Values EFR Q Values High Ref. Q Values Low Ref. EP0 +1,98 +1,98 28,66 26,68 26,68 EP1 +2,74 / +2,60 +7,06 26,60 23,86 / 24 19,54 EP2 -1,53 +2,50 18,01 19,54 15,51 EP3 -15,33 > +0,18 0,18 15,51 < 0 EP0 (tandem) - - - 23,66 23,66 EP1 (tandem) +0,76 +6,06 20,30 19,54 14,24 Table A.1.4: Q values and Differential Q (dB) values from References for error and tandeming conditions (NEC/lab4, Mod. IRS input characteristics – SEG-4, Exp#1 and Exp#5) Conditions Differential Q Values (High Ref) Differential Q Values (Low Ref) Q Values EFR Q Values High Ref. Q Values Low Ref. EP0 +3,70 +3,70 26,32 22,62 22,62 EP1 -1,50 +5,50 22,50 24 17,00 EP2 +4,63 +6,76 21,63 17,00 14,87 EP3 -10,49 +2,70 4,38 14,87 1,68 EP0 (tandem) - - - 19,32 19,32 EP1 (tandem) +2,92 +8,49 19,92 17,00 11,43 ETSI ETSI TR 101 085 V8.0.0 (2000-06) 23 (GSM 06.55 version 8.0.0 Release 1999) Table A.1.5: Q values and Differential Q (dB) values from References for error and tandeming conditions (MOTOROLA/lab5, Mod. IRS input characteristics) Conditions Differential Q Values (High Ref) Differential Q Values (Low Ref) Q Values EFR Q Values High Ref. Q Values Low Ref. EP0 - - 24,82 ? - EP1 -4,41 +3,79 19,59 24 15.80 EP2 -1,17 +3,35 14,63 15,80 11,28 EP3 -7,23 > +4,05 4,05 11,28 < 0 EP0 (tandem) - - - - - EP1 (tandem) - - - 15,80 - Table A.1.6: Q values and Differential Q (dB) values from References for error and tandeming conditions (COMSAT/lab6) Conditions Differential Q Values (High Ref) Differential Q Values (Low Ref) Q Values EFR Q Values High Ref. Q Values Low Ref. EP0 – (flat input) +1,39 +1,39 31,03 29,64 29,64 EP1 (Mod. IRS) ~ +2,79 > +5,86 > 25 -(24) 19,14 EP2 (Mod. IRS) +1,03 +4,15 20,17 19,14 14,99 EP3 - - 14,99 - EP0 (tandem) – (flat input) (G.728) +2,35 (G.721) (G.728) +2,35 (G.721) 28,78 (G.728) 26,43 (G.721) (G.728) 26,43 (G.721) EP1 (tandem) – (flat input) - - - 19.14 - Extra Conditions (not included in SEG-4, High and Low references not formally defined) G.721 (same condition) TCH-FS (same condition) EP0 –16 dBmOL – (flat input) +2,31 (G.721) +7,80 34,40 32,09 (G.721) 27,32 EP0 –36 dBmOL – (flat input) -0,61 (G.721) +2,41 25,08 25,69 (G.721) 22,67 C/I 10 dB, 1.5 mph (Mod. IRS) > +5,99 > 25 19,01 C/I 13 dB (Mod. IRS) > +4,04 > 25 20,96 C/I 13 dB tandem (Mod. IRS) > +9,80 > 25 15,20 EP1 tandem EFR/TCH- FS – (flat) - 24,46 - EP1 tandem EFR/G.721 – (flat) +2,93 27,36 24,43 Differences compared to the SEG-4: Different input characteristics (flat, except for error conditions), Additional input levels, tandemings and standards, G.721 as extra High Reference, Different MNRU selection, Separate experiment for error conditions (Non static, no frequency hopping 10 and 7 dB C/I, 30 mph, typical urban multipath, Mod. IRS input characteristics, MNRUmax = 25), No EP3 experiment. ETSI ETSI TR 101 085 V8.0.0 (2000-06) 24 (GSM 06.55 version 8.0.0 Release 1999) Table A.1.7: Q values and Differential Q (dB) values from References for error and tandeming conditions (NOKIA/lab7) Conditions Differential Q Values (High Ref) Differential Q Values (Low Ref) Q Values EFR Q Values High Ref. Q Values Low Ref. EP0 > +2,12 > +2,12 > 30 27,88 27,88 EP1 ~ -3 +14,79 27,88 - (MNRU25 31,97) 13,09 EP2 +4,90 +8,65 17,99 13,09 9,34 EP3 -7,49 > +1,85 1,85 9,34 < 0 EP0 (tandem) - - - 21,85 21,85 EP1 (tandem) +5,63 +7,99 18,72 13,09? 10,73 Extra conditions (not included in SEG-4) C/I 13 dB - > 14,91 > 30 - 15,09 Table A.1.8: Q values and Differential Q (dB) values from References for error and tandeming conditions (TI/lab8, Mod. IRS input characteristics –SEG-4, Exp#1 and Exp#5) Conditions Differential Q Values (High Ref) Differential Q Values (Low Ref) Q Values EFR Q Values High Ref. Q Values Low Ref. EP0 +2,36 +2,36 20,41 18,05 18,05 EP1 -5,21 +5,15 18,79 24 13,64 EP2 -0,48 +2,60 13,16 13,64 10,56 EP3 - - - 10,56 - EP0 (tandem) - - - 17,18 17,18 EP1 (tandem) +1,03 +5,16 14,67 13,64 9,51 A.2 Quality under Background noise conditions Table A.2.1: DMOS (and CI) values for EFR codec, G.728 Reference and TCH-FS (for lab1 to lab4, flat input characteristics – SEG-4, Exp#2 and Exp#3) Conditions Lab1 BT Lab2 CNET Lab3 TD Lab4 NEC EFR Vehicle 10 4,36 (0,17) 4,49 (0,12) 4,26 (0,16) 4,44 (0,18) EFR Music 20 4,29 (0,15) 4,55 (0,11) 4,20 (0,14) 4,48 (0,18) G.728 Vehicle 10 4,54 (0,15) 4,47 (0,14) 4,59 (0,13) 4,48 (0,14) G.728 Music 20 4,46 (0,13) 4,52 (0,17) 4,24 (0,11) 4,52 (0,16) TCH-FS Vehicle 10 4,20 (0,17) 4,50 (0,11) 4,16 (0,16) 4,06 (0,19) TCH-FS Music 20 3,36 (0,15) 3,47 (0,15) 3,11 (0,15) 3,31 (0,20) ETSI ETSI TR 101 085 V8.0.0 (2000-06) 25 (GSM 06.55 version 8.0.0 Release 1999) Table A.2.2: DMOS (and CI) values for EFR codec, G.728 Reference and extra Standards (for lab5 to lab8, flat input characteristics Conditions Lab6/Comsat (1) (2) Lab7/Nokia (1) Differences compared to SEG-4: EFR Vehicle 10 - 4,47 (0,12) EFR Music 20 - 4,57 (0,10) 1) Different selection of G.728 Vehicle 10 - 4,45 (0,12) MNRUs with noise added G.728 Music 20 - 4,46 (0,11) for Lab6 and Lab7. TCH-FS Vehicle 10 - 3,75 (0,15) 2) Different noise types, TCH-FS Music 20 - 3,54 (0,17) G.721 as High Reference, Extra Conditions (not included in SEG-4) Additional standards for Lab6. EFR Home 20 dB 4,79 (0,08) - EFR Vehicle 15 dB 4,61 (0,10) - EFR Vehicle 25 dB 4,65 (0,09) - EFR Street 10 dB 4,41 (0,13) - EFR Office 20 dB 4,66 (0,10) - TCH-FS Home 20 dB 4,35 (0,12) - TCH-FS Vehicle 15 dB 4,06 (0,13) - TCH-FS Vehicle 25 dB 4,15 (0,14) - TCH-FS Street 10 dB 3,54 (0,18) - TCH-FS Office 20 dB 3,86 (0,15) - G.721 Home 20 dB 4,67 (0,11) - G.721 Vehicle 15 dB 4,56 (0,11) - G.721 Vehicle 25 dB 4,65 (0,10) - G.721 Street 10 dB 3,90 (0,17) - G.721 Office 20 dB 4,49 (0,12) - A.3 Quality for Talker Dependency (DMOS and SD) Table A.3.1: DMOS (and SD) for EFR codec and G.728 for talker dependency (lab1 to lab4, flat, - SEG-4, Exp#4) Conditions Lab1 BT Lab2 CNET Lab3 TD Lab4 NEC EFR Male Talkers 4,89 (0,38) 4,70 (0,46) 4,77 (0,45) 4,41 (0,73) EFR Female Talkers 4,91 (0,29) 4,65 (0,56) 4,81 (0,47) 4,49 (0,65) EFR Children 4,82 (0,39) 4,65 (0,53) 4,83 (0,43) 4,48 (0,71) G.728 Male Talkers 4,56 (0,59) 4,32 (0,57) 4,34 (0,61) 4,36 (0,74) G.728 Female Talkers 4,61 (0,59) 4,41 (0,55) 4,36 (0,56) 4,35 (0,74) G.728 Children 4,80 (0,46) 4,40 (0,52) 4,38 (0,57) 4,50 (0,71) Table A.3.2: DMOS (and SD) for EFR codec and G.728 for talker dependency (lab7, flat) Conditions EFR G.728 Male Talkers 4,73 (0,51) 4,49 (0,57) Female Talkers 4,64 (0,50) 4,43 (0,56) Children 4,62 (0,59) 4,37 (0,58) Differences compared to SEG-4: Different selection of MNRUs, extra condition (TCH-FS), 16 listeners instead of 24 ETSI ETSI TR 101 085 V8.0.0 (2000-06) 26 (GSM 06.55 version 8.0.0 Release 1999) Annex B: Change Request History Change history SMG No. Tdoc. No. CR. No. Section affected New version Subject/Comments SMG#19 5.0.0 Phase 2+ version SMG#22 4.0.0 Phase 2 version SMG#27 6.0.0 Release 1997 version SMG#29 7.0.0 Release 1998 version SMG#31 8.0.0 Release 1999 version ETSI ETSI TR 101 085 V8.0.0 (2000-06) 27 (GSM 06.55 version 8.0.0 Release 1999) History Document history V8.0.0 June 2000 Publication |
cd40c3e2f3776f330b4d764b60472458 | 101 196 | 1 Scope | The present document gives guidelines for use of the DVB interaction channel for Cable TV distribution systems (CATV) specification ETS 300 800 [1]. Hybrid Fibre Coax (HFC) networks are a sub-class of CATV networks in which the subscribers are divided into groups by using optical transmission technology in the trunk network. The CATV infrastructures can support the implementation of the RC for interactive services suitable for DVB broadcasting systems. CATV can be used to implement interactive services in the DVB environment, providing a bi-directional communication path between the user terminal and the service provider. |
cd40c3e2f3776f330b4d764b60472458 | 101 196 | 2 References | References may be made to: a) specific versions of publications (identified by date of publication, edition number, version number, etc.), in which case, subsequent revisions to the referenced document do not apply; or b) all versions up to and including the identified version (identified by "up to and including" before the version identity); or c) all versions subsequent to and including the identified version (identified by "onwards" following the version identity); or d) publications without mention of a specific version, in which case the latest version applies. A non-specific reference to an ETS shall also be taken to refer to later versions published as an EN with the same number. [1] ETS 300 800: "Digital Video Broadcasting (DVB); Interaction channel for Cable TV distribution systems (CATV)". (known also as the "DVB-RCC spec). [2] EN 300 429: "Digital Video Broadcasting (DVB); Framing structure, channel coding and modulation for cable systems". (known also as the "DVB-C spec). [3] ITU-T Recommendation I.363: "B-ISDN ATM Adaptation Layer (AAL) specification". |
cd40c3e2f3776f330b4d764b60472458 | 101 196 | 3 Abbreviations | For the purposes of the present document, the following abbreviations apply: AAL5 ATM Adaptation Layer 5 ATM Asynchronous Transfer Mode BC Broadcast Channel BIM Broadcast Interface Module BRA Basic Rate Access CATV Cable TV distribution system CB radio Citizens' Band radio DAVIC Digital Audio - Visual Council EMC ElectroMagnetic Compatibility FIP Forward Interaction Path HFC Hybrid Fibre Coax IB In-Band IC Interaction Channel ID IDentifier IEEE Institute of Electrical and Electronics Engineers IIM Interactive Interface Module TR 101 196 V1.1.1 (1997-12) 6 INA Interactive Network Adapter IP Internet Protocol IRD Integrated Receiver Decoder ISDN Integrated Services Digital Network LAN Local Area Network LLC Link Layer Control MAC Media Access Control MPEG Moving Picture Export Group NIU Network Interface Unit ONU Optical Node Unit OOB Out-Of-Band OSI Open Systems Interconnection PSTN Public Switched Telephone Network RC Return Channel RCC Return Channel - Cable RIP Return Interaction Path RMS Root Mean Square SDH Synchronous Digital Hierarchy SMATV Satellite Master Antenna Television SNR Signal to Noise power Ratio STB Set Top Box STU Set Top Unit TCP Transmission Control Protocol TDMA Time Division Multiple Access TS Transport Stream UC Upstream Channel VCI Virtual Channel Identifier VPI Virtual Path Identifier |
cd40c3e2f3776f330b4d764b60472458 | 101 196 | 4 System model | Figure 1 shows the system model which is to be used within DVB for interactive services. In the system model, two channels are established between the service provider and the user: - Broadcast Channel (BC): A uni-directional broadband BC including video, audio and data. BC is established from the service provider to the users. It may include the Forward Interaction Path (FIP). - Interaction Channel (IC): A Bi-directional interaction channel is established between the service provider and the user for interaction purposes. It is formed by: - Return Interaction Path (RIP): From the user to the service provider. It is used to make requests to the service provider or to answer questions. Also commonly known as Return Channel (RC) or Upstream Channel (UC). - Forward Interaction Path (FIP): From the service provider to the user. It is used to provide some sort of information by the service provider to the user and any other required communication for the interactive service provision. It may be embedded into the BC. It is possible that this channel is not required in some simple implementations which make use of the BC for the carriage of data to the user. In the present document the word "channel" denotes logical link and "path" corresponds to a physical link. The user terminal is formed by the Network Interface Unit (NIU) (consisting of the Broadcast Interface Module (BIM) and the Interactive Interface Module (IIM)) and the Set Top Unit (STU). The user terminal provides interface for both broadcast and interaction channels. The interface between the user terminal and the interaction network is via the IIM. TR 101 196 V1.1.1 (1997-12) 7 Figure 1: Generic system reference model for interactive systems The interactive system is composed of FIP (downstream) and RIP (upstream). The general concept is to use FIP to act as a transmission medium for MAC control channel and to carry a part of the downstream data. This allows the NIUs to adapt to the network and send synchronized information upstream. RIP is divided into time slots which can be used by different users, using the technique of Time Division Multiple Access (TDMA). One MAC control channel is used to control up to 8 UCs, which are all divided into time slots. A time marker and an upstream counter at the INA is sent periodically to the NIUs, so that all NIUs work with synchronized clock and same upstream counter value. This gives the opportunity to the INA to assign time slots to different users. Three major access modes are provided with this system. The first one is based on contention access, which lets users send information at any time with the risk to have a collision with other user's transmissions. The second and third modes are contention-less based, where the INA either provides a finite amount of slots to a specific NIU, or a given bit rate requested by a NIU until the INA stops the connection on NIU's demand. These access modes are dynamically shared among time slots, which allows NIUs to know when contention based transmission is or is not allowed. This is to avoid a collision for the two contention-less based access modes. Periodically, the INA will indicate to new users that they have the possibility to go through sign-on procedure, in order to give them the opportunity to synchronize their clock to the network clock, without risking collisions with already active users. This is done by leaving a larger time interval for new users to send their information, taking into account the propagation time required from the INA to the NIUs and back. |
cd40c3e2f3776f330b4d764b60472458 | 101 196 | 5 Protocol stack model | For asymmetric interactive services supporting broadcast to the home with narrowband RC, a simple communication model consists of the following layers: Network dependent physical layer: Where all the physical (electrical) transmission parameters are defined. Network dependent access mechanism layer: Defines all the relevant data structures and communication protocols like data containers, etc. Network independent application layer: Is the interactive application software and runtime environments (e.g. home shopping application, script interpreter, etc.). DVB-RCC (ETS 300 800 [1]) addresses the lower two layers (the physical and transport) leaving the application layer open to competitive market forces. TR 101 196 V1.1.1 (1997-12) 8 A simplified model of the OSI layers was adopted to facilitate the production of specifications for these nodes. Figure 2 points out the lower layers of the simplified model and identifies some of the key parameters for the lower two layers. Following the user requirements for interactive services, no attempt will be made to consider higher medium layers in the present document. Layer Structure for Generic System Reference Model Modulation Channel coding Freq. range Filtering Equalisation Power Access mechanism Packet structure Higher medium layers Proprietary layers (Network Dependent Protocols) Network Independent Protocols Figure 2: Layer structure for generic system reference model The present document addresses the HFC/CATV network specific aspects only. The network independent protocols will be specified separately. |
cd40c3e2f3776f330b4d764b60472458 | 101 196 | 6 Specification outline | A multiple access scheme is defined in order to have different users share the same transmission media. Downstream information is sent broadcast to all users of the networks. Thus, an address assignment exists for each user which allows the INA to send information singlecast to one particular user. Two addresses are stored in Set Top Boxes (STB) in order to identify users on the network: MAC address: It is a 48-bit value representing the unique MAC address of the NIU. This MAC address may be hard coded in the NIU or be provided by external source. NSAP address: It is a 160-bit value representing a network address. This address is provided by higher layers during communication. Upstream information may come from any user in the network and shall therefore also be differentiated at the INA using the set of addresses defined above. This interactive system is based either on Out-Of-Band (OOB) or In-Band (IB) downstream signalling. However, STBs do not need to support both systems. In the case of OOB signalling, a Forward Information Path (FIP) is added. The presence of this added FIP is in that case mandatory. However, it is also possible to send higher bit rate downstream information through a DVB-C channel whose frequency is indicated in the FIP. In the case of IB signalling, the FIP is embedded into the MPEG2-TS of a DVB-C channel. NOTE: It is not mandatory to include the FIP in all DVB-C channels. Both systems can provide the same quality of service. However, the overall system architecture will differ between networks using IB STBs and OOB STBs. Both types of systems may exist on the same networks under the condition that different frequencies are used for each system. TR 101 196 V1.1.1 (1997-12) 9 Upstream and OOB downstream channels are divided into separate channels of 1 MHz or 2 MHz bandwidth for downstream and 1 MHz, 2 MHz or 200 kHz for upstream. Each downstream channel contains a synchronization frame used by up to 8 different UCs, whose frequencies are indicated by the Media Access Control (MAC) protocol. Within UCs, users send packets with TDMA type access. This means that each channel is shared by many different users, who can either send packets with a possibility of collisions when this is allowed by the INA, or request transmission and use the packets assigned by the INA to each user specifically. Assuming each upstream path can therefore accommodate a large number of users at the same time, the upstream bandwidth can easily be used by all users present on the network at the same time. The TDMA technique utilizes a slotting methodology which allows the transmit start times to be synchronized to a common clock source. Synchronizing the start times increases message throughput of this signalling channel since the message packets do not overlap during transmission. The period between sequential start times are identified as slots. Each slot is a point in time when a message packet can be transmitted over the signalling link. The time reference for slot location is received via the downstream channels generated at the delivery system and received simultaneously by all STUs. This time reference is not sent in the same way for OOB and IB signalling. Since all NIUs reference the same time base, the slot times are aligned for all NIUs. However, since there is propagation delay in any transmission network, a time base ranging method accommodates deviation of transmission due to propagation delay. Since the TDMA signalling link is used by NIUs that are engaged in interactive sessions, the number of available message slots on this channel is dependent on the number of simultaneous users. When messaging slots are not in use, a NIU may be assigned multiple message slots for increased messaging throughput. Additional slot assignments are provided to the NIU from the downstream signalling information flow. There are different access modes for the upstream slots: - reserved slots with fixed rate reservation (Fixed rate access: the user has a reservation of one or several time slots in each frame enabling, e.g. for voice, audio.); - reserved slots with dynamic reservation (Reservation access: the user sends control information announcing his demand for transmission capacity. He gets grants for the use of slots.); - contention based slots (These slots are accessible for every user. Collision is possible and solved by a contention resolution protocol.); - ranging slots (These slots are used upstream to measure and adjust the time delay and the power.). These slots may be mixed on a single carrier to enable different services on one carrier only. If one carrier is assigned to one specific service, only those slot types will be used which are needed for this service. Therefore, a terminal can be simplified to respond to only those slot types assigned to the service. |
cd40c3e2f3776f330b4d764b60472458 | 101 196 | 6.1 Bit rates and framing | For the interactive downstream OOB channel, a rate of 1,544 Mbit/s or 3,088 Mbit/s may be used. For downstream IB channels, no other constraints than those specified in DVB-C (EN 300 429 [2]) exist, but a guideline would be to use rates multiples of 8 kbit/s. Downstream OOB channels continuously transmit a frame based on T1 type framing, in which some information is provided for synchronization of upstream slots. Downstream IB channels transmit some MPEG2-TS packets with a specific PID for synchronization of upstream slots (at least one packet containing synchronization information shall be sent in every period of 3 ms). For upstream transmission, the INA can indicate three types of transmission rates to users, specifically 3,088 Mbit/s, 1,544 Mbit/s or 256 kbit/s. The INA is responsible of indicating which rate may be used by NIUs. It would imply all NIUs to be able to either transmit with 256 kbit/s, 1,544 Mbit/s, or 3,088 Mbit/s. Only the implementation of one of these bit rates would be mandatory. TR 101 196 V1.1.1 (1997-12) 10 Upstream framing consists of packets of 512 bits (256 symbols) which are sent in a bursty mode from the different users present on the network. The upstream slot rates are: 6 000 upstream slots/s when the upstream data rate is 3,088 Mbit/s; 3 000 upstream slots/s when the upstream data rate is 1,544 Mbit/s; and 500 upstream slots/s when the upstream data rate is 256 kbit/s. |
cd40c3e2f3776f330b4d764b60472458 | 101 196 | 6.2 Lower physical layer specification | In this subclause, detailed information is given on the lower physical layer specification. Figures 3, 4, 5, and 6 show the conceptual block diagrams for implementation. Figure 3: Conceptual block diagram for the NIU OOB transceiver TR 101 196 V1.1.1 (1997-12) 11 Figure 4: Conceptual block diagram for the OOB head-end transceiver Figure 5: Conceptual block diagram for the IB NIU transceiver TR 101 196 V1.1.1 (1997-12) 12 Figure 6: Conceptual block diagram for the IB head-end transceiver |
cd40c3e2f3776f330b4d764b60472458 | 101 196 | 6.3 MAC layer specification | |
cd40c3e2f3776f330b4d764b60472458 | 101 196 | 6.3.1 MAC reference model | This subclause is limited to the definition and specification of the MAC layer protocol. The detailed operations within the MAC layer are hidden from the above layers. This subclause focuses on the required message flows between the INA and the NIU for MAC. These areas are divided into three categories: Initialization, Provisioning and Sign-On Management, Connection Management and Link Management. TR 101 196 V1.1.1 (1997-12) 13 Higher Layers Physical Multicast Address Resolution Singlecast Address Resolution Data Adaptation M A C Sublayer MAC Signaling Connection Management MAC Management Entity Initialization, Sign-On and Provisioning Management Link Management Physical M A C LLC IEEE 802 Reference M odel L o w e r L a y e r P r o t o c o l s Figure 7: MAC reference model |
cd40c3e2f3776f330b4d764b60472458 | 101 196 | 6.3.2 MAC concept | Up to 8 QPSK UCs can be related to each downstream channel which is designated as a MAC control channel. An example of frequency allocation is shown in the figure 8. This relationship consists of the following items: 1) each of these related UCs share a common slot position. This reference is based on 1 ms time markers that are derived via information transmitted via the downstream MAC control channel; 2) each of these related UCs derive slot numbers from information provided in the downstream MAC control channel; 3) the messaging needed to perform MAC functions for each of these related UCs is transmitted via the downstream MAC control channel. The MAC protocol supports multiple downstream channels. In instances where multiple channels are used, the INA shall specify a single OOB frequency called the provisioning channel, where NIUs perform initialization and provisioning functions. If both 1,544 Mbit/s and 3,088 Mbit/s downstream OOB channels coexist on the network, there should be one provisioning channel with each rate. Also, in networks where IB NIUs exist, provisioning should be included in at least one IB channel. An aperiodic message is sent on each downstream control channel which points to the downstream provisioning channel. In instances where only a single frequency is in use, the INA shall utilize that frequency for initialization and provisioning functions. The MAC protocol supports multiple UCs. One of the UCs shall be designated the service channel. The service channel shall be used by NIUs entering the network via the initialization and provisioning procedure. The remaining UCs shall be used for upstream data transmission. In cases where only one UC is utilized, the functions of the service channel shall reside in conjunction with regular upstream data transmission. TR 101 196 V1.1.1 (1997-12) 14 Figure 8: Example of frequency allocation |
cd40c3e2f3776f330b4d764b60472458 | 101 196 | 6.3.3 MAC messages | The MAC message types are divided into the logical MAC states of initialization, sign-on, connection management and link management. Messages in italic represent upstream transmission from NIU to INA. MAC messages are sent using broadcast or singlecast addressing. Singlecast address shall utilize the 48-bit MAC address. Table 1: MAC messages Message Type Value Addressing Type 0x01 0x02 0x03 0x04 0x05 0x06 0x07 0x08-0x1F MAC Initialization, Provisioning and Sign-On Message Provisioning Channel Message Default Configuration Message Sign-On Request Message Sign-On Response Message Ranging and Power Calibration Message Ranging and Power Calibration Response Message Initialization Complete Message [Reserved] Broadcast Broadcast Broadcast Singlecast Singlecast Singlecast Singlecast 0x20 0x21 0x22 0x23 0x24 0x25 0x26 0x28 0x29 0x2A 0x2B-0x3F MAC Connection Establishment and Termination Messages Connect Message Connect Response Message Reservation Request Message Reservation Response Message (unused in the present version) Connect Confirm Message Release Message Release Response Message Reservation Grant Message Reservation ID Assignment Reservation Status Request [Reserved] Singlecast Singlecast Singlecast Broadcast Singlecast Singlecast Singlecast Broadcast Singlecast Singlecast 0x27 0x40 0x41 0x42 0x43 0x44 0x45-0x5F MAC Link Management Messages Idle Message Transmission Control Message Reprovision Message Link Management Response Message Status Request Message Status Response Message [Reserved] Singlecast Scast or Bcast Singlecast Singlecast Singlecast Singlecast TR 101 196 V1.1.1 (1997-12) 15 To support the delivery of MAC related information to and from the NIU, a dedicated virtual channel shall be utilized. The Virtual Path Identifier (VPI),Virtual Channel Identifier (VCI) for this channel shall be 0x000,0x0021. Upstream MAC messages: AAL5 (as specified in ITU-T Recommendation I.363 [3]) adaptation shall be used to encapsulate each MAC PDU in an ATM cell. Upstream MAC information should be single 40 bytes cell messages. Downstream OOB MAC messages: AAL5 (as specified in ITU-T Recommendation I.363 [3]) adaptation shall be used to encapsulate each MAC PDU in an ATM cell. Downstream OOB MAC information may be longer than 40 bytes. Downstream IB MAC messages: Downstream IB MAC information is limited to 120 bytes long messages (A procedure to be able to send longer messages is under definition by the DVB Project). No AAL5 layer is defined for MPEG2-TS cells. |
cd40c3e2f3776f330b4d764b60472458 | 101 196 | 7 Network architecture and services | The network architecture varies substantially from place to place. This is due to the age of the network, the history of the operator and the price of services. Most of the existing networks have a RC installed on both the fibre and the coaxial part, and the limiting part is usually the coaxial part. It is important to note however, that some networks are not yet interconnected and only local interactivity is possible at the present time. In order to connect interactive service providers to INAs, an area network should be installed between INAs. DVB-RCC (ETS 300 800 [1]) was therefore designed to have enough flexibility to accommodate all types of services on all types of networks having RC capabilities. However, flexibility is obtained by giving a certain number of tools which do not have to all be implemented, depending on the services that are to be offered on the networks. The following subclauses present different types of networks, services, and use of the tools provided. |
cd40c3e2f3776f330b4d764b60472458 | 101 196 | 7.1 Examples of services | The following list enumerates services that are already provided by DVB-C (EN 300 429 [2]) and the new services offered by DVB-RCC (ETS 300 800 [1]). Digital broadcast services (DVB): - broadcast of audio, video, and data via a distribution network. No interaction by the user. Interactive broadcast services (DVB-RC): - Responses appreciated in broadcast programs (votes, bids, games etc.) - Pay TV, Pay per View, Near Video on Demand (NVoD) - Home shopping - Banking TV based multimedia services: - Video on demand (movies, news, feature film, adverts) - Distant learning - Home shopping - Information retrieval - Games Other services (PC-based, not covered by the DVB Project, for information): - Data communication - Voice (telephony) - Information retrieval - Access to online services - LAN emulation TR 101 196 V1.1.1 (1997-12) 16 |
cd40c3e2f3776f330b4d764b60472458 | 101 196 | 7.2 Examples of networks with interactive services | Most of the HFC networks are constituted of a fibre part and a coaxial part. Figure 9 illustrates a typical HFC network configuration. The head-end delivers the signal to the Optical Node Unit (ONU), which then distributes the signal to other trunk amplifiers and finally to the coax part. The coax is then divided into several users. While the broadcasting is simply done from the head-end to all NIUs on the network, the upstream transmission is a multiplex of all NIUs signals. This multiplex is defined so that the bandwidth allocation is close to optimal, depending on the services requested by NIUs. The relationship between figure 1 and figure 9 is mostly an implementation issue which depends on the network design. Clearly the INA can be put at different levels in the diagram of figure 9. The closer it is to the broadcast network interface, the more NIUs shall be supported by the INA. Due to the bandwidth limitation, the INAs should probably be installed closer to the NIUs and an interconnection area network should support the traffic between all INAs on the network connected to servers (interactive service providers). This area network is not shown in figure 9. Head End ONU Trunk amplifier Bridger Tap Line extender Figure 9: Typical HFC network |
cd40c3e2f3776f330b4d764b60472458 | 101 196 | 7.3 Possible links between servers and HFC networks | While HFC networks are nowadays constituted of separate head-ends with a broadcast distribution network connected to them for the purpose of broadcasting, they need to be interconnected to extend the capabilities of interactive services. Depending on the services that are going to be offered, different links can exist. For services such as Video on Demand (VoD) or data banks access, it is possible to connect an ATM network to the head-ends (this can use an existing SDH network). For Internet access, it is possible to be connected through an Ethernet or fast Ethernet connection. Finally, for telephony services, it may be better to be connected through a switch to the PSTN. While the present document is typically designed to use an ATM protocol, it is not necessary to have an ATM network as the interconnection network. For instance, there can be simply one ATM node on the head-end side and several ATM nodes on the NIU sides, but the head-end can be connected to servers and other head-ends through any type of network as long as the INA is designed to interface between the HFC modem and the other network. |
cd40c3e2f3776f330b4d764b60472458 | 101 196 | 7.4 Frequency use | Figure 10 indicates a possible spectrum allocation. Although not mandatory, a guideline is provided to use the following preferred frequency ranges, 70 MHz - 130 MHz and/or 300 MHz - 862 MHz for the FIP (downstream OOB) and 5 MHz - 65 MHz for the RIP (upstream), or parts thereof. To avoid filtering problems in the bi-directional video amplifiers and in the STBs, the upper limit 65 MHz for the upstream flow shall not be used together with the lower limit 70 MHz for the downstream flow in the same system. TR 101 196 V1.1.1 (1997-12) 17 QPSK interactive 1 or 2 MHz downstream OOB channel Freq (MHz) Downstream Upstream .... .... QPSK interactive 1 or 2 MHz or 200 KHz upstream 862 DVB-C QAM 7/8 MHz channels 70-130 MHz 300-862 MHz 5 - 65 MHz Figure 10: Preferred frequency ranges for CATV interactive systems |
cd40c3e2f3776f330b4d764b60472458 | 101 196 | 7.5 Impairments analysis | There are different types of impairments that exist on HFC networks. These impairments can be categorized into the following sections: Transfer function: The transfer function depends on cables, amplifiers, filters, diplexers, that are located between the INA and the NIUs. A typical transfer function for an HFC network equipped with a RC between 5 MHz and 45 MHz is shown in the figures 11 and 12. Since the bandwidth used by the signal in ETS 300 800 [1] is relatively thin (200 kHz, 1 MHz or 2 MHz), the transfer function is flat enough so that no equalizer is required at the INA to compensate for amplitude variations, except perhaps in the highest part of the spectrum. -33 -28 -23 0 5 10 15 20 25 30 35 40 45 50 55 60 Frequency (MHz) Gain (dB) Figure 11: Typical return path gain TR 101 196 V1.1.1 (1997-12) 18 Group delay: The group delay is also dependent on the components installed on the network. Figure 12 shows the group delay for the same network as above. 4 6 8 0 5 10 15 20 25 30 35 40 45 50 55 60 Frequency (MHz) Group delay (µs) Figure 12: Typical return path group delay Ingress noise: Ingress noise is a narrowband interference that appears and disappears relatively slowly at different times of the day. The source can be anywhere in the network. It may be caused by temperature variations, CB radio transmitters, washing machines or dishwashers, and other radiating sources at the users premises. Different parameters characterize ingress noise, specifically the average duration of the noise, the frequency, and the level of the noise. Figures 13, 14 and 15 show some measurements related to these parameters on typical HFC networks. The present document offers three different types of bandwidth as well as frequency agility in order to avoid jammed frequencies. The lowest rate (256 kbit/s) is spread over a 200 kHz bandwidth, which is relatively thin in order to avoid narrowband interference. For the frequencies where low levels of noise occur, higher rates are provided over 1 MHz and 2 MHz bandwidth. TR 101 196 V1.1.1 (1997-12) 19 Figure 13: Life expectancy of ingress jammers taking into account the CB radio band or not Figure 14: Number of ingress jammers recorded over a 40 hours period TR 101 196 V1.1.1 (1997-12) 20 Figure 15: Number of ingress jammers occurrences at different levels Impulsive noise Impulsive noise is characterized by short duration broadband jammers. They are caused by electric switches, lightning, and other short duration noise. No precise measurements are yet available, but it is important to note that the present document tolerates impulse noise of 3-byte long. This corresponds to approximately 94 µs tolerance at the rate of 256 kbit/s, 15 µs at the rate of 1,544 Mbit/s, and 8 µs at the rate of 3,088 Mbit/s. |
cd40c3e2f3776f330b4d764b60472458 | 101 196 | 7.6 Dimensioning of networks | The dimensioning of networks depends strongly on the traffic that will be generated by the services offered to users. There are up to 65 536 slots available by TDMA cycle, that is 500 slots per second for 256 kbit/s, 3 000 slots/s for 1,544 Mbit/s, and 6 000 slots/s for 3,088 Mbit/s for each bandwidth that is shared between users. That means that if 30 MHz of bandwidth are used on the same network, around 90 000 slots are available per second. Figure 16 indicates the average rate offered to users as a function of the total number of users connected to the networks and assuming that at most 10 % of the slots are used for MAC processing and 30 % throughput is achieved for these messages due to collisions. 1 10 100 1000 10000 10 100 500 1000 5000 Number of users Rate (kb/s) Figure 16: Estimated average rate per user as a function of the number of users connected. TR 101 196 V1.1.1 (1997-12) 21 Figure 16 indicates that if the entire bandwidth of 30 MHz is used, the ETS 300 800 [1] provides almost 10 kbit/s in average for each user even if 5 000 users are all connected to the same INA. More than 5 000 users can be connected if separate head-ends are used. This number corresponds to a single INA receiver. |
cd40c3e2f3776f330b4d764b60472458 | 101 196 | 8 Tools provided by the physical and MAC layer |
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