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This reduces stored energy in the electric field, reducing antenna Q while also reducing losses. The elevation pattern might be distorted with grating lobes. SWR (standing wave ratio) is typically 1.5:1 or less over several octaves of frequency. [4] A discone antenna consists of three main parts: the disc, the cone, and the insulator.
The top shows the directive pattern of a horn antenna, the bottom shows the omnidirectional pattern of a simple vertical dipole antenna. In the field of antenna design the term radiation pattern (or antenna pattern or far-field pattern) refers to the directional (angular) dependence of the strength of the radio waves from the antenna or other ...
Omnidirectional radiation patterns are produced by the simplest practical antennas, monopole and dipole antennas, consisting of one or two straight rod conductors on a common axis. Antenna gain (G) is defined as antenna efficiency (e) multiplied by antenna directivity (D) which is expressed mathematically as: =.
Hence, the monopole antenna has a radiation pattern identical to the top half of the pattern of a similar dipole antenna, and a radiation resistance a bit less than half of a dipole. Since all of the equivalent dipole's radiation is concentrated in a half-space, the antenna has twice the gain (+3 dB) of a similar dipole, neglecting power lost ...
Typical antenna parameters are gain, bandwidth, radiation pattern, beamwidth, polarization, impedance; These are imperative communicative means. The antenna pattern is the response of the antenna to a plane wave incident from a given direction or the relative power density of the wave transmitted by the antenna in a given direction. For a ...
It is the only type of directional antenna that is directional ("beam" antenna) over its entire working range. discone antenna The discone is omnidirectional, vertically polarized, and has a gain similar to a dipole. It is equally efficient as a monopole and is exceptionally wideband, offering a frequency range ratio of up to approximately 10:1 .
A reconfigurable antenna is an antenna capable of modifying its frequency and radiation properties dynamically, in a controlled and reversible manner. [2] In order to provide a dynamic response, reconfigurable antennas integrate an inner mechanism (such as RF switches, varactors, mechanical actuators or tunable materials) that enable the intentional redistribution of the RF currents over the ...
A truncated biconical antenna showing the typical "mace head" shape. In radio systems, a biconical antenna is a broad-bandwidth antenna made of two roughly conical conductive objects, nearly touching at their points. [1] Biconical antennas are broadband dipole antennas, typically exhibiting a bandwidth of three octaves or more.