A novel UWB rugby-ball antenna for near-range microwave radar system

Design and performance of a monostatic ultra-wideband (UWB) microwave radar system is described in this paper. Design details are presented for a novel rugby-ball antenna and UWB resistive duplexer of the radar system. The antenna is fed through the image ground plane and backed by a reflector. Intersection of two circular areas of different radii of curvature makes up the antenna element. Antenna bandwidth is determined by upper and lower radii of curvature of the antenna element. UWB (0.1-20 GHz) voltage standing-wave ratio (percent bandwidth of 198%) was achieved, which is suitable for detection of ultrashort electric pulses. An extended time sampling method was used for the receiver section of the radar system. Analysis and performance results are described for the sampling unit and resistive duplexer. Measurement results are presented for the far-field radiation of the antenna. A comparison of range measurement was performed using the UWB antenna in a monostatic radar system with a standard trapezoidal UWB bi-static configuration. The range measurement error was improved from 3.37 % to 1.59 % using the present rugby-ball antenna in a monostatic radar configuration.