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687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 6.5.2.1 Modulation | At the Ku-band, modulation for DVB systems are normally of the type QPSK (Quadrature Phase Shift Keying). However, at the L ,S and C band, Inmarsat systems, for instance, uses Offset-QPSK for mobile systems. O-QPSK allows the amplifier to be driven more into saturation. Modulation for the new systems at Ka-band is generally chosen as QPSK, which also is the same as for ACTS, which also indicates that one is not prepared to drive the SSPA into saturation mode to increase the power efficiency even if the terminal power amplifier at the Ka-band is a cost driving element for the terminal price at the moment. The modulation can also influence the spectrum sidelobes when an amplifier is driven into saturation. Some systems plan to use TCM with 8 PSK for gateways. Higher order modulation, like 16QAM, could be an option, given it was made adaptive, to increase the capacity. 16QAM will be used for some satellite (64 kbps) services in the Inmarsat system. An Canadian experiment called BASE, (Broadband ATM over Satellite) mentioned 16QAM modulation as one topic for experiments. However, the final reports had no mentioning of such trials. Also, Asia SkyLink mentions 16QAM used at Ka-band system. In L-band and S-band systems, modulation has often been chosen so as to mimimize side-lobes of the spectrum when an amplifier was driven into saturated mode. For the Ka-band systems, such use of amplifiers is not typical, as power availability is not limited as for battery operated systems. Further, modulation schemes like offset-QPSK tend to require more processing for synchronization when the same performance is desired, than QPSK. This is an important factor when demodulation is to be performed in the satellite. Finally, as the ACTS satellite used QPSK and 8-PSK modulation, this is now considered proven technology for the Ka- band, and does as such provide some comfort for the systems design engineers. The major motivation for utilizing the Ka-band is to provide high bandwidth services. Therefore, adaptive modulation can be imagined so that the spectrum is used as efficiently as possible. The use of adaptive modulation, adapted to the fading is possible, at least from the conceptual point of view. As the terminals need to have a spare power reserve, they could apply this power for sending more bits per symbol when not required for combating rain-fading. It could also be combined with the use of BPSK, so more power per bit was used when required. Naturally, the transmission rates would be influenced, but for Internet type of applications, this may not be of negative concern. Potential use of adaptive modulation could benefit from an ETSI standard, because manufactures making terminals and satellites for different systems could then make ASICs that handled the selected types appropriately. More cost-efficient designs are important, as the terminal price is of concern for all systems. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 6.5.2.2 Coding for low BER | To obtain a sufficiently low BER, in the region of 10-8 to 10-10, powerful coding will often be required. Typically, a convolutional forward error correcting code, FEC, is used with a Viterbi decoded, combined with a Reed-Salomon code and an interleaver. There is an increasing interest for Turbo codes, but no broadband systems have so far defined the use of such codes, as they are considered to processing demanding for the broadband use. However, they could provide more coding gain, thereby allowing a reduction of the antenna size of satellite power amplifier. As the decoding rate of the terminals often is seen to be required to handle a high rate TDM downlink, implementation will most probably need to be done through the use of ASICs. As for the modulation, a standard for coding may provide the market with cheaper terminal and satellite technology. ETSI TR 101 374-1 V1.2.1 (1998-10) 35 |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 6.5.3 Terminal power amplifiers | The transmitted power density for the terminals will need to be regulated, so as the different systems do not interfere. As the terminal power amplifiers are a cost-driving factor at the Ka-band, getting a set of standard requirements may inspire the funding houses to get the prices down as they may see one larger market. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 6.5.4 The effect of delay in communications | Satellite path delay is approximately 270 milliseconds for GEO systems. Adding system delay caused by processing and buffering adds the total well above 300 ms. In voice communications, the most noticeable effect of path delay has been echo, and challenges have related to echo cancellers. Where data transfer for computers is concerned, delays are generally more tolerable than errors. The requirement for low error rates for computer-data, therefore results in requirements for high power transponders to obtain a sufficient low carrier to noise ration at the receiver. File transfer and data distribution is not very sensitive to a few hundred ms delay. However, current versions of TCP/IP, for instance, can have a limited upper-bound capacity when a given delay through the channel. These issues will be resolved, and the Internet over satellites can be as for terrestrial connections. Voice and video distribution services can on the other hand manage surprizingly high error rates (in the order of a few percent) when properly designed. As real-time systems, however, the humans interfacing with the voice and video technology, will generally accept only limited amounts of delay. Currently, many people are disturbed by the long delays in a satellite connection, in particular if it is present both ways on a duplex channel. With a bent pipe satellite and more than one users connected via satellites in different parts of the globe, a total of four satellite "hops" is possible in a practical situation. This will in most cases be unacceptable for duplex audio and video. One hop, on the other hand, is usually acceptable for most people, and indeed, the geostationary NASA ACTS satellite has been used for voice connections, and NASA reports that users did not complain about the delay, but all may not agree on that. In interactive satellite networks, propagation or path delay has presented unique problems for voice communications and earlier generations of data protocols, but problems have been overcome by the use of equipment and protocols specifically suited to the requirements of satellite transmission. Client/server applications often rely on "transaction-oriented" application-layer protocols that consist of large numbers of low bandwidth requests and responses. Delay influences the set-up of such connections. Main issues regarding latency in Internet protocols relate to: - The default buffer-size in many TCP/IP protocol implementations acts as a bottleneck on communications over high-latency links. - TCP includes congestion control mechanisms which mean that Internet connections (such as viewing web pages and sending e-mail) start out at low speed and then advance up to higher speed if no congestion is encountered. The problem is that each cycle of speed increase requires a full round-trip communication between sender and receiver, and dozens of such round-trips can be necessary to reach the full potential of a link. With a sufficiently long delay, as encountered in some GEO systems, the communication can end before the connection can ever reach the full bandwidth of the link. The above issues are one set of arguments for LEO and MEO systems. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 6.5.5 Modes of operation | The different terminals modes of operation broadband satellite system can have may vary. The below list is an indication of what can be found: - New: The terminal is unused, uninstalled and unconfigured. Not recognized by a network. - Off: The terminal is switched off, but installed. - Idle / cold standby: The terminal has logged on to the system, but is not receiving or transmitting. - Ready / hot standby: The terminal is in synchronism, and ready to transmit. (May include a minimum stand-by rate). ETSI TR 101 374-1 V1.2.1 (1998-10) 36 - Active: The terminal is transmitting and/or receiving. - Resynchronizing: The terminal has lost its synchronization, and is in the process of regaining it. - Synchronizing: The terminal is in the process of synchronizing to the system. As some systems envision a minimum bit rate to keep the terminals in synchronism when it is in use, a large number of users may actually consume a significant capacity, and contribute negatively to system noise for other users. This may be true even it the user is not sending any information. Typical, minimum rates are in the order of 16 kbps. This situation may for instance occur when users are surfing on the Internet and reading web-content. During that period they do not send anything but would like the system to respond immediately (without any log-on procedure) when they click to download another page. It may be of benefit to give this matter some consideration in ETSI. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 6.5.6 Synchronization | The method and concept used for synchronization can influence both the data rates and the overall noise of the systems. As mentioned above, using a minimum stand-by rate to keep the system in synchronism can contribute to increasing noise levels an unnecessary radio emission. Open loop, closed loop or feedback loop synchronization can influence the maximum bit rates for the return transmission for the terminals. It can also influence the design and the available third-party ASICs. For inter-system roaming, conceptually similar synchronization methods may be of importance. Inter-system roaming can be of interest for nomadic terminals, or for a users ability to choose different service providers with is single terminal. ETSI may want to look into to the technical requirements and ability for inter-system roaming. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 6.6 Competing broadband access technologies | |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 6.6.1 Broadband copper access - xDSL | The advent of the ADSL (Asymmetric Digital Subscriber Line) technology has opened the possibility for using the existing copper twisted pair access network for broadband access to the premizes. Copper twisted pair lines connects more than 90 % of residences in developed countries and more than 700 million locations globally. ADSL delivers an asymmetric capacity of up to 9 Mbit/s downstream and 640 kbit/s upstream, thus expanding the capacity of the existing copper telephone lines by a factor of up to 300 compared to voice grade modems and 50 compared to ISDN. Even though the full capacity can not be offered to every customer, ADSL enables the incumbent telephone companies to play a dominant role in the megabit access markets since no other access infrastructure will cover so much of the market for many years. Another xDSL technique, called Very high-Speed Digital Subscriber Line (VDSL), is expected around year 2000. It is a continuation of ADSL but for shorter lines. VDSL can increase the maximum downstream capacity to 52 Mbit/s. VDSL will be employed in combination with Fiber-to-the-curb or Fiber-to-the cabinet, covering the last drop to the premizes. Both ADSL and VDSL are perfectly suited for typical Internet traffic, where users download significantly more data than they transmit. VDSL can even support High Definition Television (HDTV) transmission over copper, requiring in the order of 20 Mbps, and even ADSL can support several VHS-quality video transmissions using MPEG-2 (or MPEG- 4). Manufactures of VDSL chip sets, in particular, may be able to provide chips where the ration of the upstream bandwidth can be traded for downstream bandwidth. A general, potential drawback, however, is that within one cable, with a number of twisted pair wires, all connections must use the same tx/rx bandwidth ratio. This is due to echo cancellation problems and the enormous dynamic range required to cancel near end echo for higher frequencies. Both ADSL and VDSL use multi-tone transmission, although there are two competing technologies for ADSL. Echo- cancellation is an option for ADSL, but is not used for VDSL, as the frequency band is divided into non-overlapping regions. Except for the higher speed processing required for VDSL, it is actually simpler from a transmission point of view, as the transmission characteristics vary much less for different lines over short distances. ETSI TR 101 374-1 V1.2.1 (1998-10) 37 For ADSL, it is often envisioned that an end-user (home user) will have an ATM.25 interface, and a small multiplexer at his premizes. Thus an ADSL modem will be able to support several services, and will probably not be used as a traditional modem of today. ADSL, as opposed to ISDN, allows coexistence with plain old analog telephony service (POTS), since the lower 25 kHz of the band is not used. VDSL even allows coexistence with ISDN, as it allows the 80 kHz or 120 kHz that ISDN requires to be unused. ADSL modems are available today from a number of different manufacturers, and commercial introductions is in general awaiting a market strategy and pricing policies. ADSL is by many seen as a "killer" for CATV-modems. ADSL is likely to be a major competitor to satellite access into the GII, and a users expectations for the satellite systems is in many cases likely to be similar as for ADSL. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 6.6.2 Cable TV modems | In the field of CATV networks, a number of operators are currently deploying Hybrid Fiber Coax (HFC) networks, aiming to provide their customers with both traditional services and broadband access. HFC is by some also considered as a viable architecture for the introduction of advanced services such as interactive services. However, the lack of financial strength and telecommunication background limits the power of cable TV operators to provide efficient services to a large community. Further, CATV modems sometimes require that users share the capacity, so that with a large number of users on a CATV-loop, the realistic bitrate per user is limited. An issue often mentioned related to CATV modems is that service providers are not as economically strong as telecom service providers, and do not have the necessary economic power to rapidly employ a large, new infrastructure for many users. The price charged today for this type of modems and use is high, as of today. There are all in all a number of other obstacles with CATV modems and systems, and many believe that their life in the market is limited when ADSL is fully introduced in the not too distant future. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 6.6.3 Optical fiber | Optical fiber has long played an essential role, and much wishful thinking has pointed out that "soon will bandwidth no longer be a problem" and "we will soon all have fiber to our homes". This is not true. It will take decades, if not centuries, before every home can be connected through an optical fiber, and meanwhile there is a need for other alternatives. Fiber to the home is therefore a long-term future scenario, while fiber to the curb is more reasonable for large portions of the population. From there on, xDSL techniques can support broadband services for many fixed users. For large business users, optical fibers is still the best alternative to satellite communications, and certainly it is quite common for new buildings to be cabled with optical communications cables. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 6.6.4 Terrestrial radio access | Broadband terrestrial radio access is another means of rapidly connecting users on a point to point (or point to multi- point) basis. 155 Mbps radio access networks are available today. However, such systems do not provide the (global) coverage that a satellite system can provide. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 6.7 Complementary technologies | |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 6.7.1 The Internet | The ability to provide Internet services has become the most important issue of future interactive broadband satellite systems. The Internet itself can contain such a vast amount of applications and services that most users need can be covered. Development of new protocols and Internet technologies will be able to increase the number of services further. Some of these include the introduction of push technologies and multicasting. ETSI TR 101 374-1 V1.2.1 (1998-10) 38 Reliable IP Multicast protocols are also an emerging standards area, and new protocols have been developed to support real-time multimedia delivery and Quality-of-Service (QoS) specifiers for multicast and unicast network services. These include the: - Real-time Transport Protocol (RTP); - Control protocol (RTCP) that works in conjunction with RTP; - Resource Reservation Protocol (RSVP); - Real-Time Streaming Protocol (RTSP). |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 6.7.2 ATM, QoS | There is a large interest in ATM over satellite. ATM stands for Asynchronous Transfer Mode, and ATM is a network technology based on transferring data in cells or packets of a fixed size. The cell used with ATM is relatively small (only 53 bytes) compared to similar units used with older technologies. Implementations of ATM support data transfer rates of from 25 Mbps to 2,5 Gbps. ATM creates a virtual channel between two points whenever data transfer begins, as opposed to TCP/IP, in which messages are divided into packets and each packet can take a different route from source to destination. The physical layer supports various transmission media with rates from kilobits per second to gigabits per second. However, due to the so called "cell-tax" (frame overhead), ATM is not often used on connections where the rate is low and capacity is a major limit (like telephone line modems). ATM supports a choice of various transfer capabilities, or ATC, (ITU definitions in I.371)or service catagories (ATM Forum definitions in TM 4.0): - Constant Bit Rate (CBR) is defined by a commited Peak Cell Rate (PCR) for the duration of the connection. - Variable Bit Rate (VBR) , where the connection is defined by a Sustainable Cell Rate and the Maximum Burst Size. Real time (RT) considerations adds a constraint on the cell transfer delay and the cell delay variation, while non-Real Time (nRT) does not. - Unspecified Bit Rate (UBR) is a “best effort” scheme. There is no commitment on errors, delays or throughput. - Available Bit Rate (ABR) is a network protocol, which is ratebased, allowing the overall bandwidth of the network to be optimized. A flow control mechanism is provided (through resource management cells), enabling modification during a connection of a guaranteed Minimum Cell Rate (MCR). - Guaranteed Frame Rate (GFR) is a frame based ATC, suitable for IP traffic, and also for Frame Relay / ATM inter-networking. It is defined by a source traffic descriptor including Peak Cell Rate (PCR), Minumum Cell Rate (MCR), Maximum Frame Size (MFS), Maximum Burst Size (MBS). The ATM adaptation layers are called: - AAL 1: For CBR services. - AAL 2: For VBR type of services; VBR may be difficult to implement with satellites. VBR is particularly well suited for video coding. - AAL 3/4: For connectionless services/data protocols; This is used for applications, such as file transfer, that can tolerate delays. - AAL 5: for high-speed data protocol. ATM supports QoS, which can guarantee a user a set of service parameters. QoS is short for Quality of Service. One of the biggest advantages of ATM over competing technologies such as Frame Relay and Fast Ethernet, is that it does support different QoS levels. ETSI TR 101 374-1 V1.2.1 (1998-10) 39 |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 6.7.3 Personal computers | The evolution of personal computers and computer SW merges the computing world and the broadcast (TV) world. Already computers can be used as TVs, and TV-sets are possible to use for Internet browsing. This development will continue, and the improvements in the ability of the equipment to support different services (and with better quality) may sometimes change the consumer behaviour. It is impossible to detail the expected changes in the personal computer system in the near future in the present document, but we can merely state that the development will have a great influence also on the need for and requirements for broadband satellites communication systems. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 6.7.4 DVB and MPEG-2 | Digital television and Digital Video Broadcasting is one of the other complementary technologies that provide a need for (personal) broadband satellite communication systems. In 1997, DVB delivered its Data Broadcasting specification to ETSI. Already Data Broadcast Networks (DBNs) making use of DVB return channels and DVB-S satellite delivery are up and running in Europe. DVB DBN operators include ASTRA, Hispasat and Eutelsat. Services include Internet. MPEG packets are fixed-length containers with 188 bytes of data (longer than ATM cells). MPEG includes Program Specific Information (PSI) so that the MPEG-2 decoder can capture and decode this packet structure. This data, transmitted with the pictures and sound, automatically configures the decoder and provides the synchronization information necessary for the decoder to produce a complete video signal at its output. The DVB approach provides great flexibility in terms of transmitted digital information, owing to its data "container" concept. DVB simply delivers to the receiver "containers" with compressed image, sound or data. No restrictions exist as to the kind of information which can be stored in these containers. The DVB Service Information acts like a header to the MPEG-container, ensuring that the receiver knows what it needs to decode. The DVB-S system is designed to cope with the full range of satellite transponder bandwidths. DVB-S is a single-carrier system. A Reed-Solomon Forward Error-Correction (FEC) overhead is used as an outer code., followed by interleaving. After this, a further error-correction system is added, using a punctured convolutional code as inner code. The amount of inner code can be adjusted to suit different circumstances (power, dish size, bit rate available). Data is modulated with QPSK. The 39 Mbit/s (or other bit rates allowed by parameter sets for a given satellite transponder) can be used to carry any combination of MPEG-2 video, audio and data. Service providers are free to deliver anything from multiple-channel SDTV, 16:9 Widescreen EDTV or single-channel HDTV, to Multimedia Data. Broadcast Network services and Internet over the air. As the DVB project has progressed, interactive TV has been identified as one of the key areas ideally suited to an entirely digital transmission system. Many DVB members have developed comprehensive plans for the introduction of interactive TV and 1997 has seen a number of large-scale trials in Europe. - The various DVB Return Channel specifications have been published by ETSI. These include DVB-RCC (Cable) and DVB-RCT (Telephone or ISDN). These are complemented by the DVB-NIP (Network Independent Protocols), based on the MPEG-2 DSM-CC (Digital Storage Media –Command and Control) again published by ETSI. - DVB has produced specifications for interactive return channels based on Public Switched Telephone Networks (PSTN), Integrated Services Digital Networks (ISDN), hybrid SMATV and satellite, DECT, LMDS and Cable Networks (CATV), including Hybrid Fibre Coaxial (HFC) Networks. The work is now concentrating on finding suitable technical solutions for Satellite Systems and Local Multipoint Microwave Systems (LDMS). - The new revised DECT Return Channel specification contains a vital "Data Service Profile for Point-to- Point Protocol (PPP)", which ties in with the DVB's Network Independent Protocols. - The new LMDS return channel specification is based on the DVB-RCC specification, currently in the final stage of approval in ETSI. - Technical specifications for the API and the Multimedia Home Platform will be produced in Summer 1998 by the DVB Technical Module. ETSI TR 101 374-1 V1.2.1 (1998-10) 40 Reference: http://www.dvb.org. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 6.7.5 Audio/Video compression techniques | Source coding algorithms like MPEG contribute significantly to the ability for satellites to transfer multimedia. The speed at which multimedia services like voice, audio and video can be provided is not independent of the coding that is used. Efficient compression like MPEG-2 can thus provide broadband services at a higher quality given the same transmission channel. For a users, it is irrelevant when downloading a video clip whether the speed or quality of which he can get video transferred with is improved by enabling a higher bit-rate or by better compression techniques. A significant amount of the multimedia content will be from audio and video sources, and raw, uncoded video requires very high rates (in the order of hundreds of Mbps) to be transferred with a good quality unless it is coded. Efficient coding, like MPEG-2, can provide high definition television with a few tens of Mbps. Advances in source coding technology can reduce these rates further. Another issues that may be further exploited in the future is the fact the, when properly designed, audio and video coders can tolerate quite high error rates; in the order of a few percent. This may lead to a higher throughput, as there is always a trade-off between the bit rate and the bit error rate. To exploit this fact in a combined system that transmits both data from analog sources like audio and video, as well as computer data, requires future work. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 6.8 Enabling technologies | Enabling technologies are technologies that make possible broadband satellite communications. Such technologies relate to: - the ability to create small spot beams; - the ability to manufacture and launch satellites cheaper; - active switching satellites, inter-satellite links; - Ka-band technologies in general, and in particular for consumer applications; - high rate digital signal processing for space applications / on-board processing; - phased array antennas; - network architecture; - low voltage and low consumption space qualified technology for digital equipment; - space qualified software development and implementation; - the presence of standards. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 7 Existing broadband access satellite systems | There are may current suppliers of Internet services over satellite. The offered bitrates range from 45 Mbps (Telenor) and down to 64 kbps. Hughes has for some time offered the DirecPC service. With DirecPC, the upstream connection is made via a land-line telephone modem to an ISP or regional uplink facility. Only the downstream path is via satellite to the users satellite dish. The service provides 400 Kbps of connectivity downstream, whereas upstream speed are conceptually limited by current modem technology and network issues (like the availability of IDSN or xDSL). PanAmSat also offers Internet services where ISPs offer a high-speed Internet service to subscribers using the PanAmSat satellite system, with speeds from 64 Kbps to 2,048 Mbps, simplex or duplex, and options for balanced or asymmetrical traffic. ETSI TR 101 374-1 V1.2.1 (1998-10) 41 Ka-Star Communications, a US company, has proposed a backbone networking service for North America using ATM technology to support broadband data speeds from 1,5 Mbps and up. This will be offered to ISPs, DBS providers and private network operators. Eutelsat also offer services like DirecPC. It is in practice impossible to compile a complete list of Internet-over-satellite suppliers, but just to indicate that there is a large activity within this field, some of them are listed below: • Telekom Austria • BankNet • Bekkoame • BT Satlink • Charter Communications • Concert • Crawford Satellite Services • Datel • DCI • Digex • Eutelsat • Gilat Satellite Comms • Global One • Globecast • GSI System • Impsat • Insat • Israsat • MCI • NASA ISN • Netsat • NSN • Orion Network Systems • Satko (GIBS) • Taide • TeleGlobe • Telekomunikacja Polska • Telenor • Telstra • Transtel • UNDP • Wilken/Afsat • Wisper Bandwidth • Worldcom |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8 Information received on BSM systems | This clause contains information supplied by proponents of broadband satellite systems in response to the questionnaire "Standardization Objectives for Broadband Satellite Multimedia" (www.etsi.org/ses/news/BroadSat.htm). |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.1 Astrolink | Astrolink International Limited is at the stage of proposal evaluation prior to contract award for a geostationary satellite project to provide high data rate communications to a full range of commercial, private sector and government users, with potentially global coverage. Initial service is planned for mid 2002. The projected budget for initial global infrastructure, consisting of 4 satellites and a ground network of control centres and gateways servicing world-wide deployed user terminals, is $2B+. Currently, the sole shareholder in Astrolink International Limited, is Lockheed Martin; other investors are soon to be announced. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.1.1 Target market | - SOHO, small, medium and large businesses. - Rural telephony. - Civil and military government users. No specific dedicated military services are envisioned; military will be treated as any commercial user. ETSI TR 101 374-1 V1.2.1 (1998-10) 42 |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.1.2 Satellite constellation | The Astrolink satellite system will ultimately consist of a maximum of nine satellites: - two at 97° West; - two at 21,5° West; - two at 2° East; - two at 130° East; - one at 175,25° East. Each satellite will have 44 user beams and 14 gateway beams, on-board switching capability and ISLs. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.1.3 Frequency bands | Astrolink will use the following frequencies in all areas; there is frequency reuse within a given region: Terminals: - Uplink: 29,5 to 30,0 GHz. - Downlink: 19,7 to 20,2 GHz. Gateways: - Uplink: 28,35 to 28,6 and 29,25 to 29,5 GHz. - Downlink: 18,3 to 18,8 GHz. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.1.4 Terminals | Three terminal types are proposed: - Class "A": 16 to 416 Kbps PA Power ~ 2W; - Class "B": 16 Kbps to 2,08 Mbps PA Power ~ 12W; - Class "C": 16 Kbps to 10,4Mbps PA Power ~ 15W. The modulation scheme on the radio interface is QPSK and its variants. The terminals listen to the satellite downlink to obtain the satellite clock and then synchronize their local clocks and continue time tracking. Minor Doppler correction is required, and is done by the terminal. The terminal installation will be performed by professionals, |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.1.5 Mobility | Initial fielding will service fixed users; mobile service is being considered for future block developments. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.1.6 Gateways and network interfaces | 14 beams per satellite are planned with the opportunity to place many Gateways in each beam. Astrolink gateways will be linked through the Astrolink satellites. Interconnection with other networks will be at local service nodes as required. ETSI TR 101 374-1 V1.2.1 (1998-10) 43 The gateways will be operated by local/country service providers and Astrolink International Limited at each satellite's Network Control Centre. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.1.7 Co-existence with other systems | Astrolink expects that compatibility problems with other systems using the same spectrum will arize. The PDF limits for NSGO operations in the FSS band are a major concern, and will need to be resolved through regulatory adjudication. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.1.8 Applications | Astrolink will offer a full range of commercial, private sector and government, high data rate, global communications. Astrolink will use an ATM transport layer for IP. Open systems and a common operating environment will be utilized to assure a wide array of compatible commercial applications are usable. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.1.9 Satellite component of UMTS | Astrolink does not have involvement in S-UMTS. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.1.10 Licensing | Application has been made to, and been approved by, FCC and ITU. Landing rights, and host nation agreements are seen as difficult regulatory areas. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.1.11 Standardization | Astrolink considers landing rights, blanket licensing, and host nation agreements to be the most relevant issues for standardization. Astrolink thinks an ETSI standard for type approval would most probably be helpful, depending on details of type approval. They would be interested in influencing the development of the standards ETSI will produce for type approval. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.2 EUTELSAT | EUTELSAT (European Telecommunications Satellite Organization) provide broadband satellite multimedia services through three projects: - EUTELSAT Multimedia platforms; - EUTELSAT Digital platforms; - SKYPLEX. These facilities are commercially available today and operational using DVB standards. In some cases the return link is by terrestrial telecommunications. EUTELSAT is a Transport Provider and, through the EUTELSAT Digital platform, an Access Provider. Service is provided to all of Europe and Mediterranean basin, Africa and parts of Asia. The major partners are Comnet/Telecom Italia; BT/Easynet; Polycom and Antenna Hungaria. ETSI TR 101 374-1 V1.2.1 (1998-10) 44 |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.2.1 Target market | Small, medium and large companies, and consumers. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.2.2 Satellite constellation | There are 12 geostationary Ku-band satellites, with up to 4 beams per satellite. Mostly, the satellite transponders are transparent. However, SKYPLEX involves on-board switching. The satellite projected lifetime is 12 years. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.2.3 Frequency bands | |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.2.4 Terminals | The Ku band downlink channel is DVB compliant. The power amplifiers tend to be of 10W and 20W, and are compliant with ETS 300 159. No Doppler correction is necessary in the terminal. Installation problems are minimized by maintaining a high level of system and individual terminal specifications and maintaining a high standard for approval of such systems/terminal to ensure the risk of poor installation is minimized. The terminal installation is today performed by professionals, but in the future may be by less qualified persons, e.g. any person able to use a PC Internet connection via modem. Receiver DVB-DATA cards are already at less than 300 ECU and these prices will go down proportionally to that of the DVB set-top boxes. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.2.5 Mobility | EUTELSAT operates in the fixed satellite service; there are no plans to support non-fixed terminals. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.2.6 Gateway and network interfaces | A single gateway is required, but more may be used. Gateways can be chained for redundancy management functions. Interconnection with other networks will be via standard interfaces. Gateways are operated by Access and/or Service and/or Content providers. Using the SKYPLEX network, data gateways can be distributed in any site under the coverage of the satellite, contributing data into a single channel (transponder) which can be received by all users simultaneously. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.2.7 Co-existence with other systems | EUTELSAT do not expect any problems with interference between their system and other systems. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.2.8 Applications | The system will carry any IP compatible application, multicast or unicast. Applications will interface using an Ethernet based gateway. The current windows size for TCP/IP over satellite limits the data rate to < 2 Mbps per user on a single session. ETSI TR 101 374-1 V1.2.1 (1998-10) 45 |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.2.9 Satellite component of UMTS | General discussions with current and potential partners are being conducted under non-disclosure agreements. Any future involvement with S-UMTS will depend on the strategic and commercial choices and alliances made within the framework of projects currently under investigation. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.2.10 Licensing | The satellite system is fully operational, with licenses being obtained from each national regulatory authority as required. EUTELSAT are participants in the GMPCS MoU, and want to see its principles applied to fixed satellite service as well as mobile, as blanket licensing is difficult to obtain for fixed satellite service. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.2.11 Standardization | EUTELSAT considers the following to be relevant issues for standardization: - RF spectrum emissions; - application interface (see DVB-MHP); - radio interface; - IF interfaces and/or antenna interfaces. EUTELSAT participates in standardization work, mainly within the DVB project. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.3 ICO | ICO will be a global Access and Transport provider, via its integrated satellite and terrestrial core network. The end-to-end cost of establishing the ICO business will be $US 4,6 billion, of which $US 3,5 billion will cover the system infrastructure costs. ICO currently has 57 international strategic investment partners, most of whom are operators of mobile telecommunications networks. ICO's European investors include DeTeMobil, BT, OTE, Swiss Telecom, Telecom Finland, PTT Netherlands, Telecom Poland, CPRM (Portugal), Navigation Maritime Bulgare, Cyprus Telecom, Telefonica de Espana and Turk Telecom. ICO will begin offering service in the year 2000. Additionally, ICO is currently engaged in a project with the European Commission named TEN-ICO-SAT. This is an ECU 1,4 million project to investigate the provision of satellite mobile multimedia via the ICO satellite network. The study includes: - a market assessment, to both identify suitable products for the European markets and estimate likely demand for them in the timeframe 2002 to 2007; - a technical assessment, to quantify the developments required to provide multimedia services. The assessment will also estimate the costs involved in developing the infrastructure and user terminals to support the new services; - a regulatory assessment, to identify any regulatory constraints which may impede the introduction or development of new multimedia satellite services; - the modelling of the variables of costs, revenues and returns, in order to understand the likely impact of different products; - a set of business cases to illustrate the findings of the study. ETSI TR 101 374-1 V1.2.1 (1998-10) 46 The geographical scope of the study extends to all 43 CEPT countries, and thus encompasses the needs and opportunities of both developed and emerging markets. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.3.1 Target market | Being assessed (see above). |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.3.2 Satellite constellation | 12 satellites in Medium-Earth orbit (MEO). |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.3.3 Frequency bands | No information provided (but 1 980 to 2 010 MHz). |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.3.4 Terminals | No information provided. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.3.5 Mobility | UMTS is a mobile service. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.3.6 Gateway and network interfaces | Standardization recommended (see below). |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.3.7 Co-existence with other systems | Through standardization (see below). |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.3.8 Applications | Being assessed (see above). |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.3.9 Satellite component of UMTS | ICO will be providing voice and data services compatible with the satellite component of UMTS/IMT-2000. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.3.10 Licensing | Being assessed (see above). |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.3.11 Standardization | The standardization of the satellite component of UMTS reflects many parallels with that of Satellite Personal Communications Networks (S-PCN); it has been recognized that system standards for global satellite systems are not appropriate and provide little or no added benefit. Areas which would benefit from standardization, however, would be: - type approval of user terminals (for adoption as harmonized standards); - standards for EMC certification; - certain elements related to the interconnection and interworking of the core network of satellite UMTS with the core network(s) of the fixed and terrestrial mobile UMTS systems. It is envizaged that these would be undertaken in co-operation with the development of standards for the terrestrial networks. ETSI TR 101 374-1 V1.2.1 (1998-10) 47 |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4 Motorola | Motorola Incorporated is developing four related wideband satellite systems: - Celestri Multimedia LEO, a global network on non-geostationary satellites operating in the Ka band: estimated cost: $US 2,3B; - Celestri GEO, a global network on geostationary satellites operating in the Ka band: estimated cost: $US 6,15B; - Millennium, a regional system for the Americas on geostationary satellites: estimated cost: $US 12,9B; - M-Star, a global network on non-geostationary satellites operating in the 40 GHz band: estimated cost: $US 1,55B. In all cases the cost associated with the development, test, launch and control of the satellite portion of the system is included on a stand alone basis. End-user subscriber terminal equipment is not included in the total projected system costs. The combined architecture represented by the systems Motorola has under development cover the following areas: - point-to-point real time symmetric connection services ranging from 64 kbps to 155 Mbps; - point-to-point, bursty, asymmetric services, in which each direction of communication uses varying amounts of bandwidth as needed, ranging up to 16 Kbps; - broadcast and multicast services using variable service areas and communication rates; - interactive and integrated broadcast and real-time response services. These services are combined and integrated with applications to serve the following market segments: - residential consumers purchasing multimedia applications (data, video and voice), for work at home, personal productivity, entertainment, education, health care and security purposes; - small businesses purchasing in the multimedia marketplace; - large multinational corporations seeking strategic multimedia applications that improve their business processes and customer responsiveness to all corners of the world; - telecommunications carriers and service providers world wide seeking to extend their reach, control and service quality to areas not presently covered well by their currents service offerings. At the present time Motorola has an MoU with Matra Marconi Space of Toulouse France for development and supply of satellite bus elements for the Celestri program. Other European development organizations are being actively pursued to support the four programs. Launch services are being pursued from within Europe and Asia as well as in the United States. As with the Iridium program Motorola will probably use multiple launch vehicle types in order to minimize launch risks associated with launch failures with any type of launcher. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.1 Celestri GEO | The Celestri GEO system is a broadband network capable of providing direct access for residential and business users anywhere in the world. The system will provide virtual real-time, high speed, broadband digital communications in the FSS. It will support residential and business communications that include: telecommuting, education, medical information access, home shopping, information services, access to on-line services and the Internet, person-to-person interactive communications, multimedia video, financial transaction processing, data base transfers, communications between LANs, training and education services, healthcare data transfer and information sharing. The Celestri Architecture supports dynamic allocation of satellite resources (bandwidth on demand). This feature allows users to pay only for the bandwidth they need, and assures efficient use of the spectrum. From an end-user perspective, requests for bandwidth will be transparent. ETSI TR 101 374-1 V1.2.1 (1998-10) 48 The network architecture for the Celestri GEO system is based on an ATM-like packet routing protocol. Users gain access to the network through bi-directional links between user terminals and satellites with packet routing accomplished through a baseband switch in each satellite. The application for authority to construct, launch and operate was filed with the FCC in July 1997, with intention to commence operation by the year 2002. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.1.1 Target market | The Celestri GEO system will operate as a non-common carrier, providing space segment capacity on a wholesale basis to a small number of service providers. It will not provide services directly to the public. Residential: It is anticipated that by the year 2002 there will be more than 200 million people connected to the Internet, with 150 million subscriptions to on-line services. Business: In addition to services for residential based SOHO and telecommuting, the business market will be targeted with specific services. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.1.2 Satellite constellation | The Celestri GEO system is comprized of five geostationary orbit satellites. These will operate in conjunction with other geostationary and non-geostationary satellites to bring the full array of broadband services to consumers and businesses world wide. The orbital slots requested are at: 139° W.L: to cover Western United States, Western Canada and Central America. 7.5° W.L: to cover Brazil, Europe, Middle East and Africa. 42° E.L: to cover Europe, Africa, Middle East, Central Russia, India and Western China. 97° E.L: to cover Central Russia, India, China, Japan, Australia and the Pacific Rim. 160° E.L: to cover Eastern China, Australia, Pacific Rim and Japan. Motorola proposes to use 750 MHz of spectrum in each direction in the Ka band for service links and 2 000 MHz in the 60 GHz band for intersatellite links. Each satellite has 32 antenna beams, 25 of which use dual orthogonal circular polarization to provide re-use patterns that effectively double the bandwidth. There will be 57 transponders per satellite, each capable of a peak data rate on uplink or downlink of 92 Mbps. By this arrangement, system capacity is multiplied by 9,5 over the coverage area for each satellite. Network connectivity is provided by two full duplex inter-satellite links per satellite using dual orthogonal circular polarization, providing a data rate up to 1 244 Gbps. Each satellite supports a throughput rate of over 7,5 Gbps, including service links and inter-satellite links, the equivalent of 260,000 bi-directional 16 kbps channels. The effective total system bandwidth is 35 625 MHz, providing over 1,25 million equivalent 16 kbps channels. The projected satellite operational lifetime is 10 years. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.1.3 Frequency bands | The Ka band frequencies are used: - Downlink: 18,8 to 19,3 GHz. ETSI TR 101 374-1 V1.2.1 (1998-10) 49 - Uplink: 28,6 to 29,1 GHz. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.1.4 Terminals | Subscriber terminals will operate at burst information rates of 64 kbps, 384 kbps, 768 kbps, 1,544 Mbps (T1), 3,152 Mbps and 51,84 Mbps. The transmit power level will be 2W for data rates up to 3,152 Mbps with antennas ranging from 0,7 to 3 metres diameter. The smaller antennas will be used in drier regions of the world whilst the larger antennas will be used where there are severe thunderstorms. The 51,84 Mbps links require power levels up to 60 W and antennas up to 3 metres for extended availability. Uplink power control will be used to minimize potential interference. Uplinks employ FMD/TDMA. Downlinks employ TDM at a burst information rate of 92,16 Mbps. QPSK modulation is used with forward error correction and a BER objective of 10 e-10. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.1.5 Mobility | The system is primarily intended for servicing fixed earth terminals. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.1.6 Gateways and network interfaces | The Celestri Architecture is designed to allow seamless connection using a variety of networking standards, including ATM, Frame Relay and TCP/IP. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.1.7 Co-existence with other systems | Interference issues between systems are being addressed within the US by the FCC as part of the licensing process. Internationally, the ITU-R Joint Task Group 4-9-11 is addressing the suitability of the provisional hard limits adopted at the WRC-97 as well as other mechanisms for sharing between GSO/NGSO and NGSO/NGSO systems. Motorola is actively participating in these groups. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.1.8 Applications | The architecture is being developed to be compatible with as many as possible known applications and to minimize constraints that might be placed upon future applications. Generally, applications will interface to the system through established standards. The architecture, however, supports the generation of protocol conversions allowing non-standard interfaces. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.1.9 Satellite component of UMTS | No information supplied. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.1.10 Licensing | Application for authority to construct, launch and operate the Celestri GEO System was filed with the FCC in July 1997. Motorola is presently participating in an industry Advisory Group in the US addressing blanket licensing of GSO terminals operating in the Ka band. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.1.11 Standardization | Celestri is interested in standardization of spectrum emissions and possibly the radio interface, which is planned to be open; there may be IPR associated with the radio interface. Motorola is presently participating in relevant standardization work within ETSI. ETSI TR 101 374-1 V1.2.1 (1998-10) 50 |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.2 Celestri Multimedia LEO | The Celestri LEO system is one cornerstone of the complete Motorola Celestri Architecture, providing global point-to- point real-time end-user communications with low delay, essentially equivalent to terrestrial communication systems. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.2.1 Target market | The Celestri LEO System will offer two categories of service: - First through Service Providers, to non-business and consumer end-users for accessing and retrieving content in real time. This class of service will provide bandwidth-on-demand access at data rates from 64 kbps up to 10 Mbps. - Second, interconnection services primarily using the 51,84 Mbps (OC-1) and 155,52 Mbps (OC-3) data rates, enabling multinational corporations and terrestrial carriers to aggregate voice and data signals. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.2.2 Satellite constellation | The Celestri Multimedia LEO System comprizes 63 active satellites, plus up to 7 in-orbit spares. They are dispersed in 7 circular orbital planes at an altitude of 1 400 km inclined at 48° with respect to the Equator, each with 9 active satellites. Each satellite will have 432 uplink beams and 260 downlink beams. The communications links employ a right-hand circular polarization and utilize a 7-cell cluster size to achieve the required frequency reuse. The minimum earth station elevation angle is 40°. The satellites have on-board switching and 6 optical inter-satellite links (ISL). The projected satellite operational lifetime is 8 years. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.2.3 Frequency bands | The Ka band frequencies are used: - Downlink: 18,8 to 19,3 GHz; 19,7 to 20,2 GHz. - Uplink: 28,6 to 29,1 GHz; 29,5 to 30,0 GHz. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.2.4 Terminals | The Celestri Architecture will provide a standard interface definition that will allow manufacturers to develop a broad range of compatible Customer Premizes Equipment products. Lower data rate CPE terminals support bandwidth-on-demand through use of a Time Division Multiplex (TDM) Demand Assigned Multiple Access (DAMA) protocol and fractional allocations of the peak information rates. A variety of customer selected options are anticipated e.g. protocol adapters, configurations to support asymmetric data rates, configurations to expand data rates by using multiple channel frequencies. Three types of user terminals are proposed: - Corporate Terminal: provides access for enterprise networking and provisional private lines at an OC-1 rate. As an option, where exceptionally high availability is required, large antennas and site diversity can be used with this option. - Small business Terminal: is a VSAT class terminal, with a nominal 0,75 metre mechanically steered antenna. - Direct-to-Home Terminal: is a VSAT class terminal designed to provide multimedia and telecommuting services. It uses a small electronically scanned array antenna, with a larger mechanically steered antenna as an option. ETSI TR 101 374-1 V1.2.1 (1998-10) 51 Terminals will be equipped to provide activation by smart card Subscriber Identity Modules (SIMs); this will allow public access to the network as well as limited subscriber mobility. Doppler correction is required for efficient spectrum usage, and is managed by co-operative processing between the satellite and the terminal. The terminal also actively and co-operatively participates in beam-to-beam and satellite-to-satellite handover processes. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.2.5 Mobility | Celestri operates in the fixed satellite service; however use of SIM card technology provides user mobility functionality. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.2.6 Gateways and network interfaces | The architecture is designed around virtual networks. Multiple independent networks may coexist within the architecture. Networks may be managed by, e.g. PTTs, corporations, service providers or application providers. Gateways will be interconnected through the satellite architecture and through existing terrestrial telecommunications infrastructures. Gateway terminals will provide all required multiple access functions internally and will connect to the constellation using a straightforward TDM DAMA format. The Gateway Terminal provides an interface to the PSTN at OC-1 (51,84 Mbps) and OC-3 (155,52 Mbps) rates. By appropriately placing distributed antenna facilities, a gateway terminal can have an availability of 99,99% or greater. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.2.7 Co-existence with other systems | Interference issues between systems are being addressed within the US by the FCC as part of the licensing process. Internationally, the ITU-R Joint Task Group 4-9-11 is addressing the suitability of the provisional hard limits adopted bat the WRC-97 as well as other mechanisms for sharing between GSO/NGSO and NGSO/NGSO systems. Motorola is actively participating in these groups. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.2.8 Applications | The Celestri architecture is designed to interface seamlessly to existing networks and equipment protocol interworking functions include ATM, TCP/IP and Frame Relay. Applications such as email, compressed video, home shopping and electronic banking will be supported. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.2.9 Satellite component of UMTS | No information supplied. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.2.10 Licensing | The application for authority to construct, launch and operate was filed with the FCC in June 1997; the system has been advance published with the ITU by the United States. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.2.11 Standardization | Celestri is interested in standardization of spectrum emissions and possibly the radio interface, which is planned to be open; there may be IPR associated with the radio interface. Motorola is presently participating in relevant standardization work within ETSI. ETSI TR 101 374-1 V1.2.1 (1998-10) 52 |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.3 Millennium | Millennium is a regional geostationary orbit satellite system operating in the fixed satellite service. The system will provide direct access for subscribers to advanced, broadband communications services, almost real-time, in much of the Western hemisphere. The system also complements existing and anticipated ground infrastructures by providing high data rate transport services for businesses. The Millennium architecture supports dynamic allocation of satellite resources (bandwidth on demand). This feature allows users to pay only for the bandwidth they need, and assures efficient use of the spectrum. From an end-user perspective, requests for bandwidth will be transparent. The network architecture for Millennium is based on an ATM-like packet routing protocol. Subscribers gain access to the network through bi-directional links between subscriber terminals and satellites with packet routing accomplished through a baseband switch in each satellite. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.3.1 Target market | The Millennium system will provide broadband services to the United States, including Puerto Rico and the US Virgin Islands, Canada, Mexico and most of Central and South America. The intention is to provide "any person, any time, any where" communications in the fixed satellite service. The Millennium system will operate as a non-common carrier, as the space segment capacity will be marketed wholesale to an established base of retail providers rather than directly to the public. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.3.2 Satellite constellation | The Millennium GEO system is comprized of four geostationary orbit satellites. The orbital slots assigned by the FCC in May, 1997 are at 91° W.L; 87° W.L; 77° W.L; 75° W.L. to cover the Americas from Canada to Chile. The 750 MHz of service link spectrum is divided into six frequency sub-bands. Each satellite has 32 downlink beams, each using two of six frequency sub-bands of the 750 MHz service band spectrum. 25 of the beams use dual orthogonal circular polarization to provide re-use patterns that effectively double the bandwidth. By this arrangement, system capacity is multiplied by 9,5 over the coverage area for each satellite, with each supporting a peak throughput rate of over 7,5 Gbps. The placement of the four satellites into distinct orbital slots permits the same bandwidth to be used for each satellite, resulting in a system re-use factor of 38 and an effective total system bandwidth of 28 500 MHz. Network connectivity is provided by two full duplex intersatellite links per satellite using dual orthogonal circular polarization, providing a data rate up to 1 244 Gbps. The projected satellite operational lifetime is 10 years. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.3.3 Frequency bands | Service links use non-contiguous bands of 500 MHz and 250 MHz of spectrum in each direction in the Ka band: - Downlink: 1 8,55 to 18,80 GHz and 19,70 to 20,20 GHz. - Uplink: 28,35 to 28,60 GHz and 29,5 to 30,00 GHz. Intersatellite links use 2 000 MHz of spectrum in the 60 GHz band: - Intersatellite link: 59,50 to 60,50 GHz and 62,50 to 63,50 GHz. Telemetry, Tracking and Control (TT&C) uses 6 MHz of spectrum in each direction in the 4/6 GHz band during launch, deployment and transfer orbit operations. ETSI TR 101 374-1 V1.2.1 (1998-10) 53 |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.3.4 Terminals | In order to support the anticipated variety of applications, the subscriber equipment will incorporate protocol adapters to encapsulate data into packets suitable for routing through the system so that point-to-point data transfers can take place seamlessly and regardless of the application and the interface to the subscriber's equipment. The bandwidth-on-demand feature enables subscribers to pay only for the system resources they need. From an end-user perspective, requests for bandwidth are transparent i.e. instantaneous bandwidth usage is governed by communications between the subscriber's terminal and the satellite. In the case of larger terminals providing services to multiple end- users, blocks of bandwidth reserved to support their anticipated peak demand can be adjusted as variations in the instantaneous demand develop. The Millennium system will support FDM/TDMA multiplexed information rates on individual ground-to-satellite links of 64 kbps, 384 kbps, 768 kbps, 1,544 Mbps (T1), 3,152 Mbps (DS1C) and 51,84 Mbps (OC-1). The transmit power level will be 2W for data rates up to 3,152 Mbps with ground antennas ranging from 0,7 to 3 metres diameter. The 51,84 Mbps links require power levels up to 60W and ground antennas up to 3 metres for extended availability. Uplink power control will be used to minimize potential interference. The TDM satellite-to-ground links operate at 92,16 Mbps. QPSK modulation is used with forward error correction and a BER objective of 10-10. Low-end terminals will be a desk-top package consisting of a video port and a PC port. High-end terminals may include a variety of optional protocol adapters to support a variety of user demands, and may combine several channels to support higher data rates. The minimum earth station elevation angle is 20°. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.3.5 Mobility | Millennium operates in the fixed satellite service. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.3.6 Gateway and network interfaces | The Millennium architecture is designed to allow seamless connection using a variety of networking standards, including ATM, Frame Relay and TCP/IP. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.3.7 Co-existence with other systems | Interference issues between systems are being addressed within the US by the FCC as part of the licensing process. Internationally, the ITU-R Joint Task Group 4-9-11 is addressing the suitability of the provisional hard limits adopted bat the WRC-97 as well as other mechanisms for sharing between GSO/NGSO and NGSO/NGSO systems. Motorola is actively participating in these groups. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.3.8 Applications | Residential services will include: work-at-home interconnection between home and office computers; educational services linking students and teachers around the hemisphere; medical information access bringing together patients and doctors; home shopping and service information products; customized news, sports, financial and other information products; on-line and Internet access; point-to-point or multipoint communications with other users including collaborative opportunities; pay-per-view video; games; magazines; newspapers and other special events. Business services will include: financial transaction processing; collaborative communications; LAN-to-LAN communications; training and education, and health care services. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.3.9 Satellite component of UMTS | Not relevant. ETSI TR 101 374-1 V1.2.1 (1998-10) 54 |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.3.10 Licensing | An application for authority to construct, launch and operate Millennium was filed with the FCC in September 1995; an order and authorization for four geostationary satellite slots was issued by the FCC in May, 1997. Motorola is presently participating in an industry Advisory Group in the US addressing blanket licensing of GSO terminals operating in the Ka band. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.3.11 Standardization | Millennium is interested in standardization of spectrum emissions and possibly the radio interface, which is planned to be open; there may be IPR associated with the radio interface. Motorola is presently participating in relevant standardization work within ETSI. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.4 M-Star | The M-Star system comprizes a constellation of interconnected low earth orbit satellites providing global point-to-point real-time end-user communications. This permits the use of relatively small, low-power and low-cost ground terminals and ensures that delays experienced by end-users are essentially equivalent to conventional terrestrial services. For interference avoidance the system employs space diversity, allowing multiple NGSO systems to operate co-coverage and co-frequency in the FSS bands. It will facilitate the growth of existing and anticipated wireless communications infrastructures by providing a readily available means for the interconnection of cell sites, Mobile Telephone Switching Offices (MTSO) and system control facilities. It will also provide high capacity global transport services for enterprise networking and other private data services. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.4.1 Target market | The M-Star System will offer two categories of service: - First category: will include voice and data transport to service providers and business customers. This class of service will provide 2,048 Mbps to and from multiple remote sites which can be backhauled to a hub at 51,84 Mbps. It can provide a two-way backhaul service or one-way point-to-multipoint or multipoint-to-point service. - Second category: will include interconnection services at up to 51,84 Mbps to enable terrestrial carriers to aggregate voice or data signals. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.4.2 Satellite constellation | The M-Star LEO System comprizes 72 active satellites, plus orbiting spares. They are dispersed in 12 circular orbital planes at an altitude of 1 350 km inclined at 47° with respect to the Equator, each with 6 active satellites. Each satellite contains multiple bent-pipe transponders, spot beam antennas pointed towards the earth and inter-satellite link antennas pointed to each of four adjacent satellites. Each satellite will have 32 beams for user service links. The communications links employ either Right-Hand or Left-Hand Circular Polarization (RHCP/LHCP). The projected satellite operational lifetime is 8 years. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.4.3 Frequency bands | The system design requires 3 GHz of spectrum in both the uplink and the downlink. - Downlink: 37,50 to 40,50 GHz; LHCP. - Uplink: 47,20 to 50,20 GHz; RHCP. ETSI TR 101 374-1 V1.2.1 (1998-10) 55 The intersatellite crosslinks are in paired bands, either RHCP or LHCP: - Inter-satellite links: 59,00 to 61,35 GHz and 61,65 to 64,00 GHz. The precize assignment of polarization and transmit/receive pairings is dependent on the specific location of the satellites in the constellation. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.4.4 Terminals | Two types of customer ground systems are proposed, each with their associated Customer Premizes Equipment: - The first is a wireless backhaul interface system for a Wireless Access Group (WAG). A WAG ground system includes two types of CPE: - The first type of CPE is a high capacity MTSO interface unit which controls the group and processes the data from remote sites at information rates up to 51,84 Mbps. - The second type of CPE in a WAG is a set of low-cost remote cell site interface units which operates in MTSO-directed mode, allowing information rates up to 2,048 Mbps. The WAG CPE architecture allows the MTSO interface unit to communicate with remote cell sites via a FDMA/TDMA format. A WAG is nominally sized to support 25 cell sites, each communicating with the MTSO at a data rate of 2,048 Mbps (E-1), however the wireless system operator has the facility to redistribute the capacity by modifying the frame. - The second type of customer ground system uses variations of one fundamental type of CPE a High Bit Rate Terminal (HBRT) that supports information rates up to 51,84 Mbps (OC-1). The fundamental HBRT provides a standard OC-1 interface with SONET/SDH framing and formatting that allows manufacturers and customers a broad range of options in developing CPE installations. In addition it is expected that other CPE configurations will be developed with other standard telecommunications interfaces. All CPE terminals use directional antennas with at least two independent beams to support make-before-break handoffs. Antenna sizes range from 0,66 metres for individual cell sites to 1,5 metres for the MTSO interface and OC-1 links. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.4.5 Mobility | M-Star operates in the fixed satellite service. |
687ea47256d0a0253a548ca8c0b1feaf | 101 374-1 | 8.4.4.6 Gateways and network interfaces | Terminals will support a wide variety of interfaces, such as: E-1, T-1 OC-1, T-3, Ethernet, FDD1, and network interconnection standards such as ATM, ISDN, X.25, Frame Relay, TCP/IP etc. |
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