What is the periodic antenna of the protocol?
The periodic antenna is a specialized type of high -frequency antenna. Unlike ubiquitous antennas, the logo antenna receives only in one direction and, unlike standard directional antennas, typical television antennas observed on the roofs can obtain a wide range of frequencies. Usually, these antennas are designed from a series of parallel metal tubes, which are large at the back and gradually shrink and create a kind of triangle. These antennas are most commonly used for specialized applications; Sometimes, however, they are used as TV antennas UHF and VHF.
Most high -frequency antennas have one pair of dipole elements, a few metal tubes that serve as an active elements of the antenna, and a number of reflectors and directors that reflect the signals on the dipole. Since the frequency that the antenna can receive is based on the physical dimensions of the dipole, the highest frequency antennas are only able to receive signs within a narrow range. Log Periodic antenna overcomes thisA shortage using a number of different dipole elements that differ in physical size and acceptance abilities according to the logarithm.
The logarithm used in designing the periodic antenna of the protocol begins with the physical size needed for the highest frequency to be accepted, which will be the smallest set of dipole elements. A logarithm is created that determines the size of the second set of dipole so that their minimum frequency intake slightly overlaps the maximum intake of the first set. This procedure is repeated and each pair of dipole elements increases with each iteration until the antenna is able to receive all frequencies required for application.
Dripol pairs of different sizes are then oriented to one axis so that the parallel among themselves, with the largest lower frequency of the dipole in the rear of the antenna and the smallest higher frequency dipole located in front. Because the phase of the received signals on one dipLU can interfere with other dipoles, each dipole is connected from the 180 degrees with another and the last. In this way, the dipoles will eventually reach a difference of 360 degrees and then increase the overall gain of the antenna in harmony.
logo periodic antennas also occur with impedance problems, the amount of electrical resistance between two elements of a single dipole. To solve this problem, it is common for metal dipole tubes to increase as diameter, as they extend, thus changing dipole impedance. Another method used for the corresponding impedance is to install small corresponding transformers of different values with each pair of dipoles, so the impedance is the same in all active antenna elements.
is an antennaa that can only see signals in one direction, such as Yagi antenna, has a reception force comparable to the ubiquitous antenna and is able to receive a much wider range of frequencies than one. Amateur radio operators who sometimes use as a television anTenny are sometimes used as television antennas, longing for operation in a wide range of frequencies. These types of antennas were also in the middle of the study for experimental transmission and intake of electricity.