Analysis of infinite arrays of probe-fed rectangular microstrip patches using a rigorous feed model

Abstract

An analysis of infinite arrays of rectangular microstrip patches with each element fed by one or two coaxial probes is presented. The probe self-impedance and the rapidly varying patch current near the feed connection point are rigorously included in the analysis by using an attachment mode derived from the corresponding cavity model solution. Two-probe-fed patches are analysed for both reduced cross-polarisation and circular-polarisation applications, and the effect of probe-to-probe coupling in the unit cell is determined. The theory generates results in excellent agreement with waveguide simulator measurements over a wide range of substrate dielectric constants and thicknesses for both one- and two-probe-fed patches, overcoming the drawbacks of previous solutions that used an idealised probe feed model. Similar solutions can be developed for other types of patch antennas and arrays.