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Modeling an antenna with 100 wire segments requires 100 3 = 1 million calculations. Increasing the number of elements by a factor of 10 requires 1000 3 = 1 billion calculations, increasing the computing time by a factor of 1000, assuming the simulation completes at all given memory limitations and such. Consequently, there are other approaches ...
Antenna modeling, especially in Amateur Radio. Widely used as the basis for many GUI-based programs on many platforms. Widely used as the basis for many GUI-based programs on many platforms. Version 2 is open source, but Versions 3 and 4 are commercially licensed.
A quad antenna is a type of directional wire radio antenna used on the HF and VHF bands. A quad is a Yagi–Uda antenna ("Yagi") made from loop elements instead of dipoles: It consists of a driven element and one or more parasitic elements; however in a quad, each of the loop elements may be square, round
A Yagi–Uda antenna's maximum directivity is 8.77 dB d = 10.92 dB i. Its gain necessarily must be less than this by the factor η, which must be negative in units of dB. Neither ERP nor EIRP can be calculated without knowledge of the power accepted by the antenna, i.e., it is not correct to use units of dB d or dB i with ERP and EIRP.
[aa] The simple antennas used to make a Yagi-Uda can either all be linear or bent linear antennas, or all loops (a quad antenna) or (rarely) a mixed combination of loops and straight-wire antennas. Yagi–Udas are used for rooftop television antennas, point-to-point communication links, and long distance shortwave communication using skywave ...
A Yagi–Uda antenna, or simply Yagi antenna, is a directional antenna consisting of two or more parallel resonant antenna elements in an end-fire array; [1] these elements are most often metal rods (or discs) acting as half-wave dipoles. [2]
In its use as a television antenna, it was common to combine a log-periodic design for VHF with a Yagi for UHF, with both halves being roughly equal in size. This resulted in much higher gain for UHF, typically on the order of 10 to 14 dB on the Yagi side and 6.5 dB for the log-periodic. [5]
Hexbeam amateur radio antenna. A hexbeam, or hexagonal-beam, is a type of a directional antenna for shortwave, most often used in amateur radio. The name comes from the hexagonal outer shape of the antenna. It may also sometimes be known as a W-antenna, referring to the shape of the driver. The design looks something like an upturned umbrella.