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This reflective array television antenna consists of eight "bowtie" dipole driven elements mounted in front of a wire screen reflector. The X-shaped dipoles give it a wide bandwidth to cover both the VHF (174–216 MHz) and UHF (470–700 MHz) bands. It has a gain of 5 dB VHF and 12 dB UHF and an 18 dB front-to-back ratio.
Slotted array UHF television broadcasting antenna. As shown by H. G. Booker in 1946, from Babinet's principle in optics a slot in a metal plate or waveguide has the same radiation pattern as a driven rod antenna whose rod is the same shape as the slot, with the exception that the electric field and magnetic field directions are interchanged; the antenna is a magnetic dipole instead of an ...
The IEEE defines the UHF radar band as frequencies between 300 MHz and 1 GHz. [3] Two other IEEE radar bands overlap the ITU UHF band: the L band between 1 and 2 GHz and the S band between 2 and 4 GHz. UHF television antenna on a residence. This type of antenna, called a Yagi–Uda antenna, is widely used at UHF frequencies.
Radial stubs are a planar component that consists of a sector of a circle rather than a constant-width line. They are used with planar transmission lines when a low impedance stub is required. Low characteristic impedance lines require a wide line. With a wide line, the junction of the stub with the main line is not at a well-defined point.
Antenna directivity is the ratio of maximum radiation intensity (power per unit surface) radiated by the antenna in the maximum direction divided by the intensity radiated by a hypothetical isotropic antenna radiating the same total power as that antenna. For example, a hypothetical antenna which had a radiated pattern of a hemisphere (1/2 ...
Antenna diversity, also known as space diversity or spatial diversity, is any one of several wireless diversity schemes that uses two or more antennas to improve the quality and reliability of a wireless link. Often, especially in urban and indoor environments, there is no clear line-of-sight (LOS) between transmitter and receiver. Instead the ...
Moxon antenna for the 20-meter band.The antenna is the faint rectangle of wires held in tension by the bent X-shaped support frame. Moxon antenna for the 2-meter band. The Moxon antenna or Moxon rectangle is a simple and mechanically rugged two-element parasitic array, single-frequency antenna. [1]
The Longley–Rice model (LR) is a radio propagation model: a method for predicting the attenuation of radio signals for a telecommunication link in the frequency range of 40 MHz to 100 GHz. [ 1 ] Longley-Rice is also known as the irregular terrain model (ITM).