Design of a compact differential dual-frequency antenna

A new compact differential dual-frequency antenna with signal layer substrate is described, and the antenna is symmetric. Compared with the conventional differential dual-frequency antenna, the split-rectangle ring ground plane is attached on the back,and the two E-shaped microstrip patches with feeding line are printed on the top of the substrate, thus the dimension of the antenna is reduced effectively. The four sunken jaws are introduced into the split-rectangle ring, which can adjust the high resonant band to the operation band(5.5GHz).Then the antenna is fabricated and measured. The realized antenna has a compact size of 14mm×28mm×0.5mm. Experimental results show that the proposed antenna can operate at 2.4 GHz(f1) and 5.5 GHz (f2)bands. Good agreement between the simulated and measured results is obtained.