Research On Dual Polarization Microstrip Antenna Array

The dual-polarization antenna system is one of the key technologies in the polarization terminal guidance radar. The conformal micro-strip antenna has been widely used for its unique good performances, especially for the objects with high speed. In view of the characteristic of the micro-strip patch antenna, a new kind of dual-polarization terminal guidance radar antenna was analyzed and designed, which will be used in the research and development of the radar system. The main contents of this paper are as follows:Firstly, some basic theories relevant to dual-polarization micro-strip patch antennas are introduced in this paper. The formula of input impedance and mutual impedance of a dual polarization square micro-strip patch antenna are derived based on the cavity theory and Green function method. The S parameter matrix is obtained from the above formula and the formula of the isolation degree between two polarization ports is achieved.Secondly, two kinds of micro-strip patch antenna unit with different structure are introduced in this paper. The input impedance, isolation degree, VSWR and radiation pattern are calculated, which are also compared with the measured results.Finally, the array antennas composed of parasitical cells are mainly researched. For the linear array with four cells, planar array with four cells and circular array with eight cells, the rational feed networks are designed and the input impedance, isolation, VSWR and radiation pattern are obtained through simulations.The above researches indicate that the design scheme of new kind of dual-polarization terminal guidance radar antenna is feasible and the concerned performance specifications can meet the need. The research of this paper provides a theoretical basis for the following practical engineering.