MICROSTRIP PHASE SHIFTER USING ARTIFICIAL MAGNETO-DIELECTRIC FOR PHASED ARRAY ANTENNA

Abstract

A microstrip phase shifter using an artificial magneto-dielectric (AMD) is presented. The split-ring resonator (SRR) based AMD raises the effective permeability of the microstrip line to greater than one so that the maximum phase shift range of the line can be increased. Mechanical tuning of the proposed AMD phase shifter can be achieved by transversely moving one or several AMD unit cells. For a single unit cell, the insertion loss is smaller than 1.1 dB, whereas the return loss is larger than 15 dB at the frequency band of interest (2.30-2.38 GHz). A different number of AMD unit cells is deposited on each output port of a four-port T-junction power divider and the maximum relative phase shift is 95 degrees at 2.38 GHz for a microstrip line with three AMD unit cells.