Quantization Error Reduction for the Phased Array with 2-bit Phase Shifter

It has been widely believed that phased array antenna should use at least 3-bit (as phase controlling bit) phase shifter to provide the satisfactory scanning capability and the unnoticeable parasitic sidelobes. In this paper, we proposed a novel phase perturbation method, namely, virtual feed approach, derived from the general concept of the phase randomization, to improve the performance for the low-cost electronic scanning antennas with 2-bit phase shifters. By using this method, problems of scanning error at small scanning angle as well as the relatively high parasitic sidelobes at large scanning angle are solved simultaneously at acceptable performance degradation.