Design of a series fed circularly polarized microstrip patch array

Abstract

A series fed circularly polarized microstrip patch array operating in S-band (2210 /spl plusmn/ 5 MHz) is designed to be used as a sub-array for a ground based antenna receiving signals from a LEO satellite. A slot-coupled square patch antenna is chosen as the array element and the circular polarization operation is obtained by feeding the antenna with two slots placed orthogonal to each other and excited with a 90/spl deg/ phase shift. The end of the feed line is terminated with a matched load to improve the bandwidth of the antenna.