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  2. Microwave antenna - Wikipedia

    en.wikipedia.org/wiki/Microwave_antenna

    A typical larger microwave antenna designed for mid to long range A parabolic satellite antenna for Erdfunkstelle Raisting, based in Raisting, Bavaria, Germany. C band horn-reflector antennas on the roof of a telephone switching center in Seattle, Washington, part of the U.S. AT&T Long Lines microwave relay network.

  3. Horn antenna - Wikipedia

    en.wikipedia.org/wiki/Horn_antenna

    The first modern horn antenna in 1938 with inventor Wilmer L. Barrow. A horn antenna or microwave horn is an antenna that consists of a flaring metal waveguide shaped like a horn to direct radio waves in a beam. Horns are widely used as antennas at UHF and microwave frequencies, above 300 MHz. [1]

  4. Vivaldi antenna - Wikipedia

    en.wikipedia.org/wiki/Vivaldi_antenna

    Vivaldi antennas are useful for any frequency, as all antennas are scalable in size for use at any wavelength. Printed circuit technology makes this type antenna cost effective for microwave frequencies 1 GHz or higher. An inexpensive Vivaldi antenna is etched upon a printed circuit board and fed with a soldered-on coaxial cable and SMA connector.

  5. Front-to-back ratio - Wikipedia

    en.wikipedia.org/wiki/Front-to-back_ratio

    In point-to-point microwave antennas, a "high performance" antenna usually has a higher front to back ratio than other antennas. For example, an unshrouded 38 GHz microwave dish may have a front to back ratio of 64 dB, while the same size reflector equipped with a shroud would have a front to back ratio of 70 dB.

  6. Microwave transmission - Wikipedia

    en.wikipedia.org/wiki/Microwave_transmission

    Antennas of 1931 experimental 1.7 GHz microwave relay link across the English Channel. The receiving antenna (background, right) was located behind the transmitting antenna to avoid interference. US Army Signal Corps portable microwave relay station, 1945. Microwave relay systems were first developed in World War II for secure military ...

  7. Low-noise block downconverter - Wikipedia

    en.wikipedia.org/wiki/Low-noise_block_downconverter

    The microwave signal from the dish is picked up by a feedhorn on the LNB and is fed to a section of waveguide. One or more metal pins, or probes, protrude into the waveguide at right angles to the axis and act as antennas, feeding the signal to a printed circuit board inside the LNB's shielded box for processing. The lower frequency IF output ...

  8. Sector antenna - Wikipedia

    en.wikipedia.org/wiki/Sector_antenna

    Typical GSM sector antenna outdoor unit. A sector antenna is a type of directional microwave antenna with a sector-shaped radiation pattern.The word "sector" is used in the geometric sense; some portion of the circumference of a circle measured in degrees of arc. 60°, 90° and 120° designs are typical, often with a few degrees 'extra' to ensure overlap and mounted in multiples when wider or ...

  9. Microwave - Wikipedia

    en.wikipedia.org/wiki/Microwave

    A telecommunications tower with a variety of dish antennas for microwave relay links on Frazier Peak, Ventura County, California. The apertures of the dishes are covered by plastic sheets to keep out moisture. Microwave is a form of electromagnetic radiation with wavelengths shorter than other radio waves but longer than infrared waves.