Compact Ultrawideband UHF Array Antenna for Through-Wall Radar Applications

A compact ultrawideband (UWB) array antenna has been developed for through-wall radar surveillance and tested using a noise radar. The operating frequency is in the UHF range, and the design is based on the concept of future wearable array antennas. The printed elliptical patch antenna element features an available bandwidth of almost 100% (325-1000 MHz) and a compact size of 10.2 X 10.2 X 0.3 cm(3) (0.14 lambda(L) X 0.14 lambda(L) X 0.004 lambda(L)). It has useful merits, including vertical polarization and omnidirectional coverage in azimuth plane. A portable eight-element antenna array, with a maximum dimension less than 1.8 m, was subsequently developed for a through-wall noise radar. This small array has been tested with uniform amplitude distributions for the preliminary beamforming evaluation.