A Parasitic Resonator-Based Diamond-Shaped Microstrip Antenna for Microwave Imaging Applications

This study proposes a new parasitic resonator-based diamond-shaped microstrip patch antenna for ultra-wideband microwave imaging applications. The antenna consists of a diamond-shaped radiating patch, partial ground plane, and four-star shape parasitic elements. The use of parasitic elements improves the antenna performance in terms of the bandwidth and gain. The proposed prototype has a compact dimension of 30 × 25 × 1.6 mm3. The antenna achieves an overall bandwidth (S11<-10dB) of 7.6 GHz (2.7–10.3 GHz) with more than 4 dBi realized gain and 80% efficiency across the radiating bandwidth. The modified structures of the design extended the usable upper frequency from 9.7 GHz to 10.3 GHz, and the lower frequency is decreased from 3.4 GHz to 2.7 GHz with maintaining the…