A Passive Phased-Array Antenna Module

In this paper, the design of a $\boldsymbol{4\times 4}$ passive phased-array antenna module is presented. The antenna array incorporates slot-coupled patch antennas with left-handed circularly-polarized (LHCP) radiation. The phase shifter employed in the system operates based on the principle of loaded-transmission line phase shifters. The proposed phase shifter has compact size, and low insertion loss and it covers full range of phase tuning. The simulation results show peak gain of 16.8 dBic and radiation efficiency of 73% at boresight at the frequency of 29 GHz.