A Novel Broadband Microstrip Patch Antenna with Small Ground Plane

A novel broadband microstrip patch antenna with a small ground plane is proposed in this paper. An additional ground radiation mode with low-frequency resonance is introduced by the small ground plane, while the patch radiation mode resonates at high frequency. The radiation patch is loaded with a pair of slots and two rows of shorting pins to obtain broadband matching. A relative bandwidth of 58.8%, from 2.11GHz-3.87GHz, is achieved for a compact size of 0.41λ₀*0.29λ₀*0.03λ₀at center operating frequency. In addition, omnidirectional radiation patterns with low cross-polarization are achieved over the operating band.