Dual-frequency Microstrip Array Antenna Design

Multi-frequency antennas enable one antenna aperture to function at several separated frequencies, reducing the number of antennas that equipments need and strengthening the concealment of the aircraft, as a result get an extensive application in the communication and in the military realm.This thesis is concerned with the design and the analysis of dual-frequency stacked microstrip antenna arrays. The detailed expressions of spectrum Green's functions for multilayer media are obtained by SDI. Make an overall research on the DCIM for computing spatial Green's functions, and put forward a Pole Positioning method to extract the surface wave components from multilayer media. Most of problems are discussed in solving the MPIE for microstrip antenna in stratified media, and on the characteristic of the rooftop functions, which are chosen as the basis functions to represent the current density. A hybrid method with FFT and biconjugate gradient (CGM-FFT) is used to calculate the current distributions on the large array antennas. A set of formulas for designing rectangle microstrip antennas are given. We fabricate and test a stacked dual-frequency microstrip array antenna whose results are shown in the end.