Simulation and analysis of a kind of cylindrical conformal Yagi-Uda antenna

Abstract

In order to save the space of aerocraft, the conformal antennas can be adopted, which also donpsilat affect the dynamics performance. This paper discusses a kind of cylindrical conformal Yagi-Uda antenna and estimates its radiation characteristics. The proposed cylindrical conformal Yagi-Uda antenna is composed of five conformal dipoles, which is mounted on the surface of the cylindrical object in order to realize the radiation toward the axis of the cylinder. At the same time, two antennas are mounted on surface of the cylinder symmetrically to form the mono-pulse antenna. The diameter of the cylinder is 300 millimeters and the position and size of the cylindrical conformal antenna are determined according to the design method of traditional Yagi-Uda antennas approximately. The radiation performances of the proposed antenna are simulated for two cases, the one case is that the substrate of the dipoles is dielectric and the other case is that the dielectric substrate of the dipoles supported by metallic conductor. The calculation results reveal that the anticipative radiation directivity is obtained and the sum and difference patterns are formed. When the frequency is 600 MHz, for the first case, the directivity of sum beam is about 9.8 dBi and the bandwidth is about 158 MHz for the voltage standing wave ratio which is less than 3, and for the second case, the directivity of sum beam is about 5.4 dBi and the bandwidth is about 190 MHz for the voltage standing wave ratio which is less than 3. The radiation performance of the first kind of antenna is better than the second kind of antenna, but the physical structure of the second kind of antenna is more firm. The simulation and calculation results in this paper can provide the technical reference for the research and development of practical cylindrical conformal antennas.