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  2. Cassegrain antenna - Wikipedia

    en.wikipedia.org/wiki/Cassegrain_antenna

    A beam waveguide antenna is a type of complicated Cassegrain antenna with a long radio wave path to allow the feed electronics to be located at ground level. It is used in very large steerable radio telescopes and satellite ground antennas, where the feed electronics are too complicated and bulky, or requires too much maintenance and alterations, to locate on the dish; for example those using ...

  3. Television antenna - Wikipedia

    en.wikipedia.org/wiki/Television_antenna

    A short antenna pole next to a house Multiple Yagi TV aerials. Antennas are commonly placed on rooftops and sometimes in attics. Placing an antenna indoors significantly attenuates the level of the available signal. [19] [20] Directional antennas must be pointed at the transmitter they are receiving; in most cases great accuracy is not needed ...

  4. Radiation pattern - Wikipedia

    en.wikipedia.org/wiki/Radiation_pattern

    In most antennas, the radiation from the different parts of the antenna interferes at some angles; the radiation pattern of the antenna can be considered an interference pattern. This results in minimum or zero radiation at certain angles where the radio waves from the different parts arrive out of phase , and local maxima of radiation at other ...

  5. Antenna measurement - Wikipedia

    en.wikipedia.org/wiki/Antenna_measurement

    An antenna designer must take into account the application for the antenna when determining the gain. High-gain antennas have the advantage of longer range and better signal quality, but must be aimed carefully in a particular direction. Low-gain antennas have shorter range, but the orientation of the antenna is inconsequential.

  6. Numerical Electromagnetics Code - Wikipedia

    en.wikipedia.org/wiki/Numerical_Electromagnetics...

    In antenna terms, each of the conductors making up the antenna is known as an element. [9] To calculate the net result, NEC breaks the antenna's elements into a number of sampled points, called segments. It uses simple calculations based on the diameter of the conductor and the wavelength of the signal to determine the induced voltage and ...

  7. Antenna diversity - Wikipedia

    en.wikipedia.org/wiki/Antenna_diversity

    Antenna diversity is especially effective at mitigating these multipath situations. This is because multiple antennas offer a receiver several observations of the same signal. Each antenna will experience a different interference environment. Thus, if one antenna is experiencing a deep fade, it is likely that another has a sufficient signal ...

  8. Low-noise block downconverter - Wikipedia

    en.wikipedia.org/wiki/Low-noise_block_downconverter

    Today "dual LNB" (and "dual feed") describes antennas for reception from two satellite positions, using either two separate LNBs or a single Monoblock LNB with two feedhorns. In the UK, the term "twin-output LNB", or simply "twin LNB", is usually used for an LNB with a single feedhorn but two independent outputs.

  9. TiVo digital video recorders - Wikipedia

    en.wikipedia.org/wiki/TiVo_digital_video_recorders

    All standalone TiVo systems have coax/RF-in and an internal cable-ready tuner, analog video input—composite/RCA, and S-Video—for use with an external cable box or satellite receiver. The TiVo unit can use a serial cable or IR blasters to control the external receiver.