A compact and broadband microstrip patch antenna

A novel square microstrip patch antenna with a single-patch and single-layer structure is demonstrated. By incorporating an air-filled substrate with a thickness of around 0.08 /spl lambda//sub 1/ and having one patch edge shorted with three shorting-pins, an impedance bandwidth (return loss <-10dB) of 67.5% from 3.62 GHz to 7.32 GHz is obtained for this probe-fed compact and broadband antenna. The details of antenna design, analyses, and measurement results are presented and discussed.