Synthesis Method for Filtering Antennas Based on Multiple Radiation Port Topology

In this paper, a synthesis method is proposed for designing filtering antennas. Based on the multiple radiation port topology, the prediction of antenna radiation characteristics is achieved by combining the filter synthesis theory with the pattern multiplication theory for array. Firstly, the conventional coupling matrix is expanded according to the number of radiation ports, and the transmission coefficients of each radiation port are calculated from the expanded coupling matrix. Subsequently, the radiation characteristics of the antenna can be calculated based on the transmission coefficient and the gain of each radiation port. The proposed method can be used to design filtering antennas with different topologies and can be used to analyze the impedance response of different antennas. For verification, antennas with the same radiation structure are designed according to different coupling matrices to obtain different radiation characteristic.