A dual-band shorted patch antenna proximity-fed by a combined L- and Tprobe feed structure

Measured results of a dual-band shorted patch antenna excited by a combined L- and T- probe feed structure are presented. By using foam layers of thickness /spl sim/0.12/spl lambda//sub 1/ and /spl sim/0 06/spl lambda//sub 2/ (/spl lambda//sub 1/ and /spl lambda//sub 2/ represent the free space wavelength at the center frequency of the lower and upper band) to support the patches that are responsible for the lower and upper band, an impedance bandwidth (SWR/spl les/2) of 54.4% and 49 1 % have been obtained respectively. The peak gain of each band is 3 8 dB for both planes. The far field patterns are stable across the passband.