A slot antenna consists of a metal surface, usually a flat plate, with one or more holes or slots cut out. When the plate is driven as an antenna by a driving. Slot radiators or slot antennas are antennas that are used in the frequency range from about MHz to 25 GHz. They are often used in navigation radar usually. The slot antenna is studied. The basic principles of slot antennas are presented, along with design parameters. Amateur Radio Stack Exchange is a question and answer site for amateur radio enthusiasts. Thus, this current flow acts as an excitation system for the slot, this one acts as radiator. For array antennas, this is not possible so easily. A sheet that was many wavelengths big, such that there was negligible current far away from the slot, would be a good approximation. You may wonder how the antenna design parameters A, B, C , monopole height and position are determined. Write for us FAQ's Helping Contact. At these frequencies, the slot length is 0. This dipole will be very similar to the slot, except:. A slot antenna consists of a metal surface, usually a flat plate, with one or more holes or slots cut. If, instead of a hole we have a conductor, and we make a very small cut in the center of this conductor so we can put a voltage source across it, we have a dipole. Note that instead of a monopole kampf der tentakel the cavity backed slot, the slot antenna could be directly fed across the slot gap. At these frequencies, the slot length is 0. In order for radiate in the correct phase, all single slots must be cutted in the distance of the wavelength, that is valid for the interior of the waveguide. This effect can also be exploited to achieve an electronic pivoting of the antenna beam as a function of change of the transmission frequency. The radiation pattern of the cavity backed slot antenna somewhat resembles that of a dipole antena in the forward H-plane. Navigation Main page Contents Featured content Current events Random article Donate to Wikipedia Wikipedia store. Join them; it only takes a minute: In the E-plane, the pattern is fairly broad, with a 3-dB beamwidht of about degrees. Navigation menu Personal tools Not logged in Talk Contributions Create account Log in. To gain an intuition about slot antennas, first we'll learn Babinet's principle put into antenna terms by H. Slot antennas are often used at UHF and microwave frequencies instead of line antennas when greater control of slot antenna radiation pattern is required. If a dipole is used for feeding of a parabolic antenna to generate a vertically orientated but horizontally polarized fan beamthen this dipole must be orientated horizontally.