Design of Wideband Monopulse Sum-Difference Beam Array Antenna

In this paper, a wideband monopulse sum-difference beam array antenna is proposed for target localization, where Vivaldi antennas are employed to transmit/receive signals. The sum-difference network is composed of four four-branch directional couplers and four broadband phase shifters. The simulation results demonstrate that the sum-difference beam array antenna can operate in the frequency band of 3.4 - 5.0 GHz with the sum-beam gain of 10.73 - 14.80 dBi and difference beam gain of 11.10 -14.33 dBi. The null depths of the difference pattern are less than -20 dB.