Time Domain Analysis of Compact, High Gain UWB Cavity-Backed Monopole Antenna

A compact (115 x 115 mm2) cavity-backed monopole unidirectional ultrawideband (UWB) antenna is proposed. The proposed antenna’s impedance bandwidth is around 90 % from 1.5-4 GHz. A prototype has been fabricated, and measurement results were obtained. The measured gain of the cavity backed antenna is 10 dBi at 2.4 GHz, which shows an improvement of 6dB (approx) compared to a traditional monopole antenna. The effect of the cavity in the antenna’s structure has been discussed. Monopole antennas are known for showing good time domain behavior. It has been demonstrated that the cavity backed UWB antenna is capable of sending narrow Gaussian pulses in the face to face configuration with acceptable (,i.e., > 0.8) fidelity factor and uniform group delay with variations less than 2 ns. The proposed UWB antenna is suitable for many wireless applications because of its good radiation characteristics and reasonable performance in time domain.