id stringlengths 24 24 | question stringlengths 1 270 | answer stringlengths 1 239 | documents listlengths 1 1 |
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572fe8da04bcaa1900d76e8f | What size antenna would not be good when the antenna needs to be directional? | small | [
"Antenna_(radio)\n\nAn antenna transmits and receives radio waves with a particular polarization which can be reoriented by tilting the axis of the antenna in many (but not all) cases. The physical size of an antenna is often a practical issue, particularly at lower frequencies (longer wavelengths). Highly directio... |
572fe936b2c2fd14005685bf | What is the basis for the way most antennas are developed? | resonance principle | [
"Antenna_(radio)\n\nThe majority of antenna designs are based on the resonance principle. This relies on the behaviour of moving electrons, which reflect off surfaces where the dielectric constant changes, in a fashion similar to the way light reflects when optical properties change. In these designs, the reflectiv... |
572fe936b2c2fd14005685c0 | What particle's migration does the resonance principle rely on? | electrons | [
"Antenna_(radio)\n\nThe majority of antenna designs are based on the resonance principle. This relies on the behaviour of moving electrons, which reflect off surfaces where the dielectric constant changes, in a fashion similar to the way light reflects when optical properties change. In these designs, the reflectiv... |
572fe936b2c2fd14005685c1 | What type of surface is formed by the tip of a conductor? | reflective | [
"Antenna_(radio)\n\nThe majority of antenna designs are based on the resonance principle. This relies on the behaviour of moving electrons, which reflect off surfaces where the dielectric constant changes, in a fashion similar to the way light reflects when optical properties change. In these designs, the reflectiv... |
572fe936b2c2fd14005685c2 | How would you place the conductor in relation to the signal you wished to obtain? | perpendicular | [
"Antenna_(radio)\n\nThe majority of antenna designs are based on the resonance principle. This relies on the behaviour of moving electrons, which reflect off surfaces where the dielectric constant changes, in a fashion similar to the way light reflects when optical properties change. In these designs, the reflectiv... |
572fe97ca23a5019007fcb23 | What part of the radio signal creates voltage? | electrical component | [
"Antenna_(radio)\n\nThe radio signal's electrical component induces a voltage in the conductor. This causes an electrical current to begin flowing in the direction of the signal's instantaneous field. When the resulting current reaches the end of the conductor, it reflects, which is equivalent to a 180 degree chang... |
572fe97ca23a5019007fcb24 | What would the electric current always gravitate to? | instantaneous field | [
"Antenna_(radio)\n\nThe radio signal's electrical component induces a voltage in the conductor. This causes an electrical current to begin flowing in the direction of the signal's instantaneous field. When the resulting current reaches the end of the conductor, it reflects, which is equivalent to a 180 degree chang... |
572fe97ca23a5019007fcb25 | What is the outcome when a curren is reflected> | 180 degree change in phase | [
"Antenna_(radio)\n\nThe radio signal's electrical component induces a voltage in the conductor. This causes an electrical current to begin flowing in the direction of the signal's instantaneous field. When the resulting current reaches the end of the conductor, it reflects, which is equivalent to a 180 degree chang... |
572fe97ca23a5019007fcb26 | What amount of phase change would return a signal to its originial state? | 360 degree | [
"Antenna_(radio)\n\nThe radio signal's electrical component induces a voltage in the conductor. This causes an electrical current to begin flowing in the direction of the signal's instantaneous field. When the resulting current reaches the end of the conductor, it reflects, which is equivalent to a 180 degree chang... |
572fe9e4b2c2fd14005685c7 | What is the most popular antenna type? | half-wave dipole | [
"Antenna_(radio)\n\nThe ordinary half-wave dipole is probably the most widely used antenna design. This consists of two 1β4-wavelength elements arranged end-to-end, and lying along essentially the same axis (or collinear), each feeding one side of a two-conductor transmission wire. The physical arrangement of the t... |
572fe9e4b2c2fd14005685c8 | Elements in a half wave dipole and on an identical axis are said to be what? | collinear | [
"Antenna_(radio)\n\nThe ordinary half-wave dipole is probably the most widely used antenna design. This consists of two 1β4-wavelength elements arranged end-to-end, and lying along essentially the same axis (or collinear), each feeding one side of a two-conductor transmission wire. The physical arrangement of the t... |
572fe9e4b2c2fd14005685c9 | What is the current usually beng put into it or pulled out of? | transmission line | [
"Antenna_(radio)\n\nThe ordinary half-wave dipole is probably the most widely used antenna design. This consists of two 1β4-wavelength elements arranged end-to-end, and lying along essentially the same axis (or collinear), each feeding one side of a two-conductor transmission wire. The physical arrangement of the t... |
572fe9e4b2c2fd14005685ca | What antenna type is a portion of the half wave dipole? | Monopoles | [
"Antenna_(radio)\n\nThe ordinary half-wave dipole is probably the most widely used antenna design. This consists of two 1β4-wavelength elements arranged end-to-end, and lying along essentially the same axis (or collinear), each feeding one side of a two-conductor transmission wire. The physical arrangement of the t... |
572fe9e4b2c2fd14005685cb | What popular type combines more that one antenna? | folded dipole | [
"Antenna_(radio)\n\nThe ordinary half-wave dipole is probably the most widely used antenna design. This consists of two 1β4-wavelength elements arranged end-to-end, and lying along essentially the same axis (or collinear), each feeding one side of a two-conductor transmission wire. The physical arrangement of the t... |
572fea66b2c2fd14005685d1 | What frequency are antennas normally designed to be? | f0 | [
"Antenna_(radio)\n\nThe standing wave forms with this desired pattern at the design frequency, f0, and antennas are normally designed to be this size. However, feeding that element with 3f0 (whose wavelength is 1β3 that of f0) will also lead to a standing wave pattern. Thus, an antenna element is also resonant when... |
572fea66b2c2fd14005685d2 | What can be added to f0 to create a standing wave pattern? | 3f0 | [
"Antenna_(radio)\n\nThe standing wave forms with this desired pattern at the design frequency, f0, and antennas are normally designed to be this size. However, feeding that element with 3f0 (whose wavelength is 1β3 that of f0) will also lead to a standing wave pattern. Thus, an antenna element is also resonant when... |
572fea66b2c2fd14005685d3 | What multiple is essential for wavelengths? | 1β4 | [
"Antenna_(radio)\n\nThe standing wave forms with this desired pattern at the design frequency, f0, and antennas are normally designed to be this size. However, feeding that element with 3f0 (whose wavelength is 1β3 that of f0) will also lead to a standing wave pattern. Thus, an antenna element is also resonant when... |
572fea66b2c2fd14005685d4 | How are waves which are used in the ways discussed controlled? | harmonically | [
"Antenna_(radio)\n\nThe standing wave forms with this desired pattern at the design frequency, f0, and antennas are normally designed to be this size. However, feeding that element with 3f0 (whose wavelength is 1β3 that of f0) will also lead to a standing wave pattern. Thus, an antenna element is also resonant when... |
572feda5b2c2fd14005685ed | How do quarter wave elements act in relation to a series relevant electrical element? | imitate | [
"Antenna_(radio)\n\nThe quarter-wave elements imitate a series-resonant electrical element due to the standing wave present along the conductor. At the resonant frequency, the standing wave has a current peak and voltage node (minimum) at the feed. In electrical terms, this means the element has minimum reactance, ... |
572feda5b2c2fd14005685ee | What frequency develops a current peak? | resonant frequency | [
"Antenna_(radio)\n\nThe quarter-wave elements imitate a series-resonant electrical element due to the standing wave present along the conductor. At the resonant frequency, the standing wave has a current peak and voltage node (minimum) at the feed. In electrical terms, this means the element has minimum reactance, ... |
572feda5b2c2fd14005685ef | How would you describe a current that has maximum efficiency? | minimum reactance | [
"Antenna_(radio)\n\nThe quarter-wave elements imitate a series-resonant electrical element due to the standing wave present along the conductor. At the resonant frequency, the standing wave has a current peak and voltage node (minimum) at the feed. In electrical terms, this means the element has minimum reactance, ... |
572feda5b2c2fd14005685f0 | What could be the best possible output versus input ratio? | lossless | [
"Antenna_(radio)\n\nThe quarter-wave elements imitate a series-resonant electrical element due to the standing wave present along the conductor. At the resonant frequency, the standing wave has a current peak and voltage node (minimum) at the feed. In electrical terms, this means the element has minimum reactance, ... |
572ff30304bcaa1900d76f12 | What could be coupled with an antenna to form pure resistance? | inductance | [
"Antenna_(radio)\n\nIt is possible to use the impedance matching concepts to construct vertical antennas substantially shorter than the 1β4 wavelength at which the antenna is resonant. By adding an inductance in series with the antenna, a so-called loading coil, the capacitive reactance of this antenna can be cance... |
572ff30304bcaa1900d76f13 | What element would this pure resistance be coupled with? | transmission line | [
"Antenna_(radio)\n\nIt is possible to use the impedance matching concepts to construct vertical antennas substantially shorter than the 1β4 wavelength at which the antenna is resonant. By adding an inductance in series with the antenna, a so-called loading coil, the capacitive reactance of this antenna can be cance... |
572ff30304bcaa1900d76f14 | What phrase describes the process of purposely using a lower standing antenna at a less than peak frequency? | electrical lengthening | [
"Antenna_(radio)\n\nIt is possible to use the impedance matching concepts to construct vertical antennas substantially shorter than the 1β4 wavelength at which the antenna is resonant. By adding an inductance in series with the antenna, a so-called loading coil, the capacitive reactance of this antenna can be cance... |
572ff31bb2c2fd140056863b | If your were unable to match the source frequency with the design frequency of the antenna what could you use? | resonant multiples | [
"Antenna_(radio)\n\nThe end result is that the resonant antenna will efficiently feed a signal into the transmission line only when the source signal's frequency is close to that of the design frequency of the antenna, or one of the resonant multiples. This makes resonant antenna designs inherently narrowband, and ... |
572ff31bb2c2fd140056863c | What is the most common application of resonant antennas? | single target signal | [
"Antenna_(radio)\n\nThe end result is that the resonant antenna will efficiently feed a signal into the transmission line only when the source signal's frequency is close to that of the design frequency of the antenna, or one of the resonant multiples. This makes resonant antenna designs inherently narrowband, and ... |
572ff31bb2c2fd140056863d | What antenna setup type is generally used for TV viewing? | resonant | [
"Antenna_(radio)\n\nThe end result is that the resonant antenna will efficiently feed a signal into the transmission line only when the source signal's frequency is close to that of the design frequency of the antenna, or one of the resonant multiples. This makes resonant antenna designs inherently narrowband, and ... |
572ff31bb2c2fd140056863e | For use with more than one channel changes are made to increase what property? | bandwidth | [
"Antenna_(radio)\n\nThe end result is that the resonant antenna will efficiently feed a signal into the transmission line only when the source signal's frequency is close to that of the design frequency of the antenna, or one of the resonant multiples. This makes resonant antenna designs inherently narrowband, and ... |
572ff545a23a5019007fcbb3 | What accounts for the geometry involved in the use of an antenna? | inverse square law | [
"Antenna_(radio)\n\nThe amount of signal received from a distant transmission source is essentially geometric in nature due to the inverse square law, and this leads to the concept of effective area. This measures the performance of an antenna by comparing the amount of power it generates to the amount of power in ... |
572ff545a23a5019007fcbb5 | How is the compactness of the signal measured? | Watts per square metre | [
"Antenna_(radio)\n\nThe amount of signal received from a distant transmission source is essentially geometric in nature due to the inverse square law, and this leads to the concept of effective area. This measures the performance of an antenna by comparing the amount of power it generates to the amount of power in ... |
572ff545a23a5019007fcbb6 | What type of project would call for more than one element used together? | higher performance | [
"Antenna_(radio)\n\nThe amount of signal received from a distant transmission source is essentially geometric in nature due to the inverse square law, and this leads to the concept of effective area. This measures the performance of an antenna by comparing the amount of power it generates to the amount of power in ... |
572ff659b2c2fd1400568661 | What is a half wave dipole need to be coupled with in most instances? | feed point | [
"Antenna_(radio)\n\nReturning to the basic concept of current flows in a conductor, consider what happens if a half-wave dipole is not connected to a feed point, but instead shorted out. Electrically this forms a single 1β2-wavelength element. But the overall current pattern is the same; the current will be zero at... |
572ff659b2c2fd1400568662 | What part of the current is usually strongest? | center | [
"Antenna_(radio)\n\nReturning to the basic concept of current flows in a conductor, consider what happens if a half-wave dipole is not connected to a feed point, but instead shorted out. Electrically this forms a single 1β2-wavelength element. But the overall current pattern is the same; the current will be zero at... |
572ff659b2c2fd1400568663 | What does this result in? | standing wave pattern | [
"Antenna_(radio)\n\nReturning to the basic concept of current flows in a conductor, consider what happens if a half-wave dipole is not connected to a feed point, but instead shorted out. Electrically this forms a single 1β2-wavelength element. But the overall current pattern is the same; the current will be zero at... |
572ff659b2c2fd1400568664 | Element used to provide support to the original signal are called? | passive elements | [
"Antenna_(radio)\n\nReturning to the basic concept of current flows in a conductor, consider what happens if a half-wave dipole is not connected to a feed point, but instead shorted out. Electrically this forms a single 1β2-wavelength element. But the overall current pattern is the same; the current will be zero at... |
572ff739b2c2fd140056866f | What can take advantage of these elements to add more gain? | Yagi-Uda array | [
"Antenna_(radio)\n\nA Yagi-Uda array uses passive elements to greatly increase gain. It is built along a support boom that is pointed toward the signal, and thus sees no induced signal and does not contribute to the antenna's operation. The end closer to the source is referred to as the front. Near the rear is a si... |
572ff739b2c2fd1400568670 | Does this device improve the operation of the antenna? | does not contribute | [
"Antenna_(radio)\n\nA Yagi-Uda array uses passive elements to greatly increase gain. It is built along a support boom that is pointed toward the signal, and thus sees no induced signal and does not contribute to the antenna's operation. The end closer to the source is referred to as the front. Near the rear is a si... |
572ff739b2c2fd1400568671 | What is the name for passive elements nearer to the source of the signal? | directors | [
"Antenna_(radio)\n\nA Yagi-Uda array uses passive elements to greatly increase gain. It is built along a support boom that is pointed toward the signal, and thus sees no induced signal and does not contribute to the antenna's operation. The end closer to the source is referred to as the front. Near the rear is a si... |
572ff739b2c2fd1400568672 | Adding more elements to a Yagi-Uda would have what effect? | increasingly directional | [
"Antenna_(radio)\n\nA Yagi-Uda array uses passive elements to greatly increase gain. It is built along a support boom that is pointed toward the signal, and thus sees no induced signal and does not contribute to the antenna's operation. The end closer to the source is referred to as the front. Near the rear is a si... |
572ff872b2c2fd140056868b | What can be paired with transmission lines to create phases that would support output? | active elements | [
"Antenna_(radio)\n\nIt is also possible to use multiple active elements and combine them together with transmission lines to produce a similar system where the phases add up to reinforce the output. The antenna array and very similar reflective array antenna consist of multiple elements, often half-wave dipoles, sp... |
572ff872b2c2fd140056868c | What is the most common element used to create a single in phase signal? | half-wave dipoles | [
"Antenna_(radio)\n\nIt is also possible to use multiple active elements and combine them together with transmission lines to produce a similar system where the phases add up to reinforce the output. The antenna array and very similar reflective array antenna consist of multiple elements, often half-wave dipoles, sp... |
572ff872b2c2fd140056868d | What must be precise in order to create this signal at output? | phase lengths | [
"Antenna_(radio)\n\nIt is also possible to use multiple active elements and combine them together with transmission lines to produce a similar system where the phases add up to reinforce the output. The antenna array and very similar reflective array antenna consist of multiple elements, often half-wave dipoles, sp... |
572ff872b2c2fd140056868e | What is a more complicated occurrence of the single in-phase producing antenna? | log-periodic | [
"Antenna_(radio)\n\nIt is also possible to use multiple active elements and combine them together with transmission lines to produce a similar system where the phases add up to reinforce the output. The antenna array and very similar reflective array antenna consist of multiple elements, often half-wave dipoles, sp... |
572ff92704bcaa1900d76f8d | If you wanted to somehow clone the original signal you could use? | extended conductive surface | [
"Antenna_(radio)\n\nReflection of the original signal also occurs when it hits an extended conductive surface, in a fashion similar to a mirror. This effect can also be used to increase signal through the use of a reflector, normally placed behind the active element and spaced so the reflected signal reaches the el... |
572ff92704bcaa1900d76f8e | What effect would the use of a reflector have on a signal? | increase | [
"Antenna_(radio)\n\nReflection of the original signal also occurs when it hits an extended conductive surface, in a fashion similar to a mirror. This effect can also be used to increase signal through the use of a reflector, normally placed behind the active element and spaced so the reflected signal reaches the el... |
572ff92704bcaa1900d76f8f | What allowance can be made for gaps without loss of performance? | less than 1β10 | [
"Antenna_(radio)\n\nReflection of the original signal also occurs when it hits an extended conductive surface, in a fashion similar to a mirror. This effect can also be used to increase signal through the use of a reflector, normally placed behind the active element and spaced so the reflected signal reaches the el... |
572ff92704bcaa1900d76f90 | What is the most recognized type of an antenna that has its basis in reflection? | parabolic reflector | [
"Antenna_(radio)\n\nReflection of the original signal also occurs when it hits an extended conductive surface, in a fashion similar to a mirror. This effect can also be used to increase signal through the use of a reflector, normally placed behind the active element and spaced so the reflected signal reaches the el... |
572ffb1ba23a5019007fcbf3 | What magnifies the small radiation resistance of a loop? | a capacitor at the frequency of operation | [
"Antenna_(radio)\n\nAnother extreme case of impedance matching occurs when using a small loop antenna (usually, but not always, for receiving) at a relatively low frequency where it appears almost as a pure inductor. Resonating such an inductor with a capacitor at the frequency of operation not only cancels the rea... |
572ffb1ba23a5019007fcbf4 | What is used in most AM broadcaster receivers? | loop | [
"Antenna_(radio)\n\nAnother extreme case of impedance matching occurs when using a small loop antenna (usually, but not always, for receiving) at a relatively low frequency where it appears almost as a pure inductor. Resonating such an inductor with a capacitor at the frequency of operation not only cancels the rea... |
572ffb1ba23a5019007fcbf5 | What is resonated by a capacitor along with the receiver tuning that maintains resonance over the AM broadcast band? | small ferrite loop antenna | [
"Antenna_(radio)\n\nAnother extreme case of impedance matching occurs when using a small loop antenna (usually, but not always, for receiving) at a relatively low frequency where it appears almost as a pure inductor. Resonating such an inductor with a capacitor at the frequency of operation not only cancels the rea... |
572ffb1ba23a5019007fcbf6 | When using a small loop antenna at a low frequency, what may occur? | impedance matching | [
"Antenna_(radio)\n\nAnother extreme case of impedance matching occurs when using a small loop antenna (usually, but not always, for receiving) at a relatively low frequency where it appears almost as a pure inductor. Resonating such an inductor with a capacitor at the frequency of operation not only cancels the rea... |
573001d0b2c2fd1400568721 | Where does cancellation of any reactance seen? | antenna terminals | [
"Antenna_(radio)\n\nAntenna tuning generally refers to cancellation of any reactance seen at the antenna terminals, leaving only a resistive impedance which might or might not be exactly the desired impedance (that of the transmission line). Although an antenna may be designed to have a purely resistive feedpoint i... |
573001d0b2c2fd1400568722 | What is left after antenna tuning? | resistive impedance | [
"Antenna_(radio)\n\nAntenna tuning generally refers to cancellation of any reactance seen at the antenna terminals, leaving only a resistive impedance which might or might not be exactly the desired impedance (that of the transmission line). Although an antenna may be designed to have a purely resistive feedpoint i... |
573001d0b2c2fd1400568723 | What can be used to cancel a inductibe reactance or residual capacitative? | parallel capacitance | [
"Antenna_(radio)\n\nAntenna tuning generally refers to cancellation of any reactance seen at the antenna terminals, leaving only a resistive impedance which might or might not be exactly the desired impedance (that of the transmission line). Although an antenna may be designed to have a purely resistive feedpoint i... |
573001d0b2c2fd1400568724 | What is an antenna designed to have? | purely resistive feedpoint | [
"Antenna_(radio)\n\nAntenna tuning generally refers to cancellation of any reactance seen at the antenna terminals, leaving only a resistive impedance which might or might not be exactly the desired impedance (that of the transmission line). Although an antenna may be designed to have a purely resistive feedpoint i... |
5730073c04bcaa1900d77037 | What type of antenna has impedance at a specific frequency? | resonant | [
"Antenna_(radio)\n\nAlthough a resonant antenna has a purely resistive feed-point impedance at a particular frequency, many (if not most) applications require using an antenna over a range of frequencies. An antenna's bandwidth specifies the range of frequencies over which its performance does not suffer due to a p... |
5730073c04bcaa1900d77038 | What term can be used to refer to the usable spectrum of an antennas frequency? | bandwidth | [
"Antenna_(radio)\n\nAlthough a resonant antenna has a purely resistive feed-point impedance at a particular frequency, many (if not most) applications require using an antenna over a range of frequencies. An antenna's bandwidth specifies the range of frequencies over which its performance does not suffer due to a p... |
5730073c04bcaa1900d77039 | What causes the frequencies outside of the bandwidth to be unusable? | impedance match | [
"Antenna_(radio)\n\nAlthough a resonant antenna has a purely resistive feed-point impedance at a particular frequency, many (if not most) applications require using an antenna over a range of frequencies. An antenna's bandwidth specifies the range of frequencies over which its performance does not suffer due to a p... |
5730073c04bcaa1900d7703a | What is lessened by the Yagi-Uda design? | directivity | [
"Antenna_(radio)\n\nAlthough a resonant antenna has a purely resistive feed-point impedance at a particular frequency, many (if not most) applications require using an antenna over a range of frequencies. An antenna's bandwidth specifies the range of frequencies over which its performance does not suffer due to a p... |
57300832a23a5019007fcc73 | What characteristic would be better if it were steady? | reactance | [
"Antenna_(radio)\n\nInstead, it is often desired to have an antenna whose impedance does not vary so greatly over a certain bandwidth. It turns out that the amount of reactance seen at the terminals of a resonant antenna when the frequency is shifted, say, by 5%, depends very much on the diameter of the conductor u... |
57300832a23a5019007fcc74 | What characteristic of the conductor changes the amount of reactance? | diameter | [
"Antenna_(radio)\n\nInstead, it is often desired to have an antenna whose impedance does not vary so greatly over a certain bandwidth. It turns out that the amount of reactance seen at the terminals of a resonant antenna when the frequency is shifted, say, by 5%, depends very much on the diameter of the conductor u... |
57300832a23a5019007fcc75 | What would be used to create a half wave or quarter wave dipole? | A long thin wire | [
"Antenna_(radio)\n\nInstead, it is often desired to have an antenna whose impedance does not vary so greatly over a certain bandwidth. It turns out that the amount of reactance seen at the terminals of a resonant antenna when the frequency is shifted, say, by 5%, depends very much on the diameter of the conductor u... |
573008dba23a5019007fcc7b | What type of tubes are generally used for sturdier always of antennas? | cages | [
"Antenna_(radio)\n\nRather than just using a thick tube, there are similar techniques used to the same effect such as replacing thin wire elements with cages to simulate a thicker element. This widens the bandwidth of the resonance. On the other hand, amateur radio antennas need to operate over several bands which ... |
573008dba23a5019007fcc7c | What effect do cages have on the spectrum of usable frequencies? | widens | [
"Antenna_(radio)\n\nRather than just using a thick tube, there are similar techniques used to the same effect such as replacing thin wire elements with cages to simulate a thicker element. This widens the bandwidth of the resonance. On the other hand, amateur radio antennas need to operate over several bands which ... |
573008dba23a5019007fcc7d | How could one achieve the task of creating an antenna that can be Used over various bands? | connecting resonant elements | [
"Antenna_(radio)\n\nRather than just using a thick tube, there are similar techniques used to the same effect such as replacing thin wire elements with cages to simulate a thicker element. This widens the bandwidth of the resonance. On the other hand, amateur radio antennas need to operate over several bands which ... |
573008dba23a5019007fcc7e | What is an essential for dealing with directing the flow of power? | trap's | [
"Antenna_(radio)\n\nRather than just using a thick tube, there are similar techniques used to the same effect such as replacing thin wire elements with cages to simulate a thicker element. This widens the bandwidth of the resonance. On the other hand, amateur radio antennas need to operate over several bands which ... |
57300a9f947a6a140053cfca | What is an acknowledgement of the range of possible direction for and antenna? | gain | [
"Antenna_(radio)\n\nGain is a parameter which measures the degree of directivity of the antenna's radiation pattern. A high-gain antenna will radiate most of its power in a particular direction, while a low-gain antenna will radiate over a wider angle. The antenna gain, or power gain of an antenna is defined as the... |
57300a9f947a6a140053cfcb | What is another way to refer to an antennas gain? | power gain | [
"Antenna_(radio)\n\nGain is a parameter which measures the degree of directivity of the antenna's radiation pattern. A high-gain antenna will radiate most of its power in a particular direction, while a low-gain antenna will radiate over a wider angle. The antenna gain, or power gain of an antenna is defined as the... |
57300a9f947a6a140053cfcc | What is the meaning of intensity? | power per unit surface area | [
"Antenna_(radio)\n\nGain is a parameter which measures the degree of directivity of the antenna's radiation pattern. A high-gain antenna will radiate most of its power in a particular direction, while a low-gain antenna will radiate over a wider angle. The antenna gain, or power gain of an antenna is defined as the... |
57300a9f947a6a140053cfcd | What type of an antenna would offer the same level of power to each possible destination? | isotropic | [
"Antenna_(radio)\n\nGain is a parameter which measures the degree of directivity of the antenna's radiation pattern. A high-gain antenna will radiate most of its power in a particular direction, while a low-gain antenna will radiate over a wider angle. The antenna gain, or power gain of an antenna is defined as the... |
57300b4ba23a5019007fccb5 | Antennas with higher gain have what positive feature? | longer range | [
"Antenna_(radio)\n\nHigh-gain antennas have the advantage of longer range and better signal quality, but must be aimed carefully at the other antenna. An example of a high-gain antenna is a parabolic dish such as a satellite television antenna. Low-gain antennas have shorter range, but the orientation of the antenn... |
57300b4ba23a5019007fccb6 | Dish network Tv takes example of what type of antenna? | parabolic dish | [
"Antenna_(radio)\n\nHigh-gain antennas have the advantage of longer range and better signal quality, but must be aimed carefully at the other antenna. An example of a high-gain antenna is a parabolic dish such as a satellite television antenna. Low-gain antennas have shorter range, but the orientation of the antenn... |
57300b4ba23a5019007fccb7 | What type of antenna would be best if placement was tricky? | Low-gain | [
"Antenna_(radio)\n\nHigh-gain antennas have the advantage of longer range and better signal quality, but must be aimed carefully at the other antenna. An example of a high-gain antenna is a parabolic dish such as a satellite television antenna. Low-gain antennas have shorter range, but the orientation of the antenn... |
57300b4ba23a5019007fccb8 | What is a measure of how much efficient is improved by adding a device designed to make something stronger? | amplifier gain | [
"Antenna_(radio)\n\nHigh-gain antennas have the advantage of longer range and better signal quality, but must be aimed carefully at the other antenna. An example of a high-gain antenna is a parabolic dish such as a satellite television antenna. Low-gain antennas have shorter range, but the orientation of the antenn... |
5730129f947a6a140053d040 | What must the relationship of an antenna and the receiving area be due to reciprocity? | proportional | [
"Antenna_(radio)\n\nDue to reciprocity (discussed above) the gain of an antenna used for transmitting must be proportional to its effective area when used for receiving. Consider an antenna with no loss, that is, one whose electrical efficiency is 100%. It can be shown that its effective area averaged over all dire... |
5730129f947a6a140053d041 | what could an antenna with complete electrical efficiency be said to have? | no loss | [
"Antenna_(radio)\n\nDue to reciprocity (discussed above) the gain of an antenna used for transmitting must be proportional to its effective area when used for receiving. Consider an antenna with no loss, that is, one whose electrical efficiency is 100%. It can be shown that its effective area averaged over all dire... |
5730129f947a6a140053d042 | hat could an antenna with complete electrical efficiency be said to have? | 1 | [
"Antenna_(radio)\n\nDue to reciprocity (discussed above) the gain of an antenna used for transmitting must be proportional to its effective area when used for receiving. Consider an antenna with no loss, that is, one whose electrical efficiency is 100%. It can be shown that its effective area averaged over all dire... |
5730129f947a6a140053d043 | Another term for the effective area is? | Aeff | [
"Antenna_(radio)\n\nDue to reciprocity (discussed above) the gain of an antenna used for transmitting must be proportional to its effective area when used for receiving. Consider an antenna with no loss, that is, one whose electrical efficiency is 100%. It can be shown that its effective area averaged over all dire... |
57301377947a6a140053d05c | A plot of the radiation behaviors of an antenna would show what? | relative field strength | [
"Antenna_(radio)\n\nThe radiation pattern of an antenna is a plot of the relative field strength of the radio waves emitted by the antenna at different angles. It is typically represented by a three-dimensional graph, or polar plots of the horizontal and vertical cross sections. The pattern of an ideal isotropic an... |
57301377947a6a140053d05d | What type of pictoral aid is often used to show this? | three-dimensional graph | [
"Antenna_(radio)\n\nThe radiation pattern of an antenna is a plot of the relative field strength of the radio waves emitted by the antenna at different angles. It is typically represented by a three-dimensional graph, or polar plots of the horizontal and vertical cross sections. The pattern of an ideal isotropic an... |
57301377947a6a140053d05e | A sphere shows what type of antennas radiation? | isotropic | [
"Antenna_(radio)\n\nThe radiation pattern of an antenna is a plot of the relative field strength of the radio waves emitted by the antenna at different angles. It is typically represented by a three-dimensional graph, or polar plots of the horizontal and vertical cross sections. The pattern of an ideal isotropic an... |
57301377947a6a140053d05f | Dipoles are considered to be what antenna type? | nondirectional | [
"Antenna_(radio)\n\nThe radiation pattern of an antenna is a plot of the relative field strength of the radio waves emitted by the antenna at different angles. It is typically represented by a three-dimensional graph, or polar plots of the horizontal and vertical cross sections. The pattern of an ideal isotropic an... |
57301377947a6a140053d060 | What would an omnidirectional antenna look like if plotted? | donut | [
"Antenna_(radio)\n\nThe radiation pattern of an antenna is a plot of the relative field strength of the radio waves emitted by the antenna at different angles. It is typically represented by a three-dimensional graph, or polar plots of the horizontal and vertical cross sections. The pattern of an ideal isotropic an... |
573014c3a23a5019007fcd25 | What is the term that refers to areas where an antennas radiation is zero? | nulls | [
"Antenna_(radio)\n\nThe radiation of many antennas shows a pattern of maxima or \"lobes\" at various angles, separated by \"nulls\", angles where the radiation falls to zero. This is because the radio waves emitted by different parts of the antenna typically interfere, causing maxima at angles where the radio waves... |
573014c3a23a5019007fcd26 | What do radio waves do that account for maxima or nulls in an antenna pattern? | interfere | [
"Antenna_(radio)\n\nThe radiation of many antennas shows a pattern of maxima or \"lobes\" at various angles, separated by \"nulls\", angles where the radiation falls to zero. This is because the radio waves emitted by different parts of the antenna typically interfere, causing maxima at angles where the radio waves... |
573014c3a23a5019007fcd27 | If you desired to project radio waves to the south, what part of the antenna would you build larger in that direction? | lobe | [
"Antenna_(radio)\n\nThe radiation of many antennas shows a pattern of maxima or \"lobes\" at various angles, separated by \"nulls\", angles where the radiation falls to zero. This is because the radio waves emitted by different parts of the antenna typically interfere, causing maxima at angles where the radio waves... |
573014c3a23a5019007fcd28 | What is the main distinction of side lobes? | represent unwanted radiation | [
"Antenna_(radio)\n\nThe radiation of many antennas shows a pattern of maxima or \"lobes\" at various angles, separated by \"nulls\", angles where the radiation falls to zero. This is because the radio waves emitted by different parts of the antenna typically interfere, causing maxima at angles where the radio waves... |
5730159ca23a5019007fcd37 | What is one piece that makes up an antenna system? | radio | [
"Antenna_(radio)\n\nAs an electro-magnetic wave travels through the different parts of the antenna system (radio, feed line, antenna, free space) it may encounter differences in impedance (E/H, V/I, etc.). At each interface, depending on the impedance match, some fraction of the wave's energy will reflect back to t... |
5730159ca23a5019007fcd38 | What is created by a portion of a radio waves energy reversing? | standing wave | [
"Antenna_(radio)\n\nAs an electro-magnetic wave travels through the different parts of the antenna system (radio, feed line, antenna, free space) it may encounter differences in impedance (E/H, V/I, etc.). At each interface, depending on the impedance match, some fraction of the wave's energy will reflect back to t... |
5730159ca23a5019007fcd39 | A term that refers to the highs and lows of power in electro magnetic waves is? | standing wave ratio | [
"Antenna_(radio)\n\nAs an electro-magnetic wave travels through the different parts of the antenna system (radio, feed line, antenna, free space) it may encounter differences in impedance (E/H, V/I, etc.). At each interface, depending on the impedance match, some fraction of the wave's energy will reflect back to t... |
5730159ca23a5019007fcd3a | Impedance matching makes an important difference in what antenna function? | power transfer | [
"Antenna_(radio)\n\nAs an electro-magnetic wave travels through the different parts of the antenna system (radio, feed line, antenna, free space) it may encounter differences in impedance (E/H, V/I, etc.). At each interface, depending on the impedance match, some fraction of the wave's energy will reflect back to t... |
57301633a23a5019007fcd3f | A measure of the power that is useable and the power absorbed by the terminals? | Efficiency | [
"Antenna_(radio)\n\nEfficiency of a transmitting antenna is the ratio of power actually radiated (in all directions) to the power absorbed by the antenna terminals. The power supplied to the antenna terminals which is not radiated is converted into heat. This is usually through loss resistance in the antenna's cond... |
57301633a23a5019007fcd40 | What happens to the power that is not absorbed by the antenna? | heat | [
"Antenna_(radio)\n\nEfficiency of a transmitting antenna is the ratio of power actually radiated (in all directions) to the power absorbed by the antenna terminals. The power supplied to the antenna terminals which is not radiated is converted into heat. This is usually through loss resistance in the antenna's cond... |
57301633a23a5019007fcd42 | What can cause that reaction? | transmitter | [
"Antenna_(radio)\n\nEfficiency of a transmitting antenna is the ratio of power actually radiated (in all directions) to the power absorbed by the antenna terminals. The power supplied to the antenna terminals which is not radiated is converted into heat. This is usually through loss resistance in the antenna's cond... |
57301ce7b2c2fd14005688a3 | What would need to be placed into the transmitter to create ten W oh warmth? | 100 W | [
"Antenna_(radio)\n\nFor instance, if a transmitter delivers 100 W into an antenna having an efficiency of 80%, then the antenna will radiate 80 W as radio waves and produce 20 W of heat. In order to radiate 100 W of power, one would need to use a transmitter capable of supplying 125 W to the antenna. Note that ante... |
57301ce7b2c2fd14005688a4 | What factor may play a hand in lessened power from a transmitter? | impedance matching | [
"Antenna_(radio)\n\nFor instance, if a transmitter delivers 100 W into an antenna having an efficiency of 80%, then the antenna will radiate 80 W as radio waves and produce 20 W of heat. In order to radiate 100 W of power, one would need to use a transmitter capable of supplying 125 W to the antenna. Note that ante... |
57301ce7b2c2fd14005688a5 | What would need to be investigated to determine how much power was radiated? | electrical measurements | [
"Antenna_(radio)\n\nFor instance, if a transmitter delivers 100 W into an antenna having an efficiency of 80%, then the antenna will radiate 80 W as radio waves and produce 20 W of heat. In order to radiate 100 W of power, one would need to use a transmitter capable of supplying 125 W to the antenna. Note that ante... |
57301dc304bcaa1900d771b3 | What can increase the feedpoint impedance of a component? | loss resistance | [
"Antenna_(radio)\n\nHowever loss resistance will generally affect the feedpoint impedance, adding to its resistive (real) component. That resistance will consist of the sum of the radiation resistance Rr and the loss resistance Rloss. If an rms current I is delivered to the terminals of an antenna, then a power of ... |
57301dc304bcaa1900d771b4 | The addition of Rr and Rloss equals what? | resistance | [
"Antenna_(radio)\n\nHowever loss resistance will generally affect the feedpoint impedance, adding to its resistive (real) component. That resistance will consist of the sum of the radiation resistance Rr and the loss resistance Rloss. If an rms current I is delivered to the terminals of an antenna, then a power of ... |
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