Differential-fed UWB patch antenna with triple band-notched characteristics

A differential-fed ultra-wideband patch antenna with triple band-notched characteristics is proposed. The antenna consists of an octagonal slot ground and two quasi-square radiating patches. By employing split-ring resonators (SRRs) etched on the radiating patch and complementary SRRs etched on the ground plane, triple-notched bands are obtained to filter the 3.5 GHz WiMAX, 5.5 GHz WLAN and 8 GHz ITU bands. The measured 10 dB impedance bandwidth is from 2.55 to 10.86 GHz, along with triple-notched bands of 3.21-3.86, 4.93-6.13 and 7.87-8.89 GHz. In addition, the proposed antenna achieves relatively low cross-polarisation and stable gain. Good agreement is achieved between the simulated and the measured results.