Effects of phase and amplitude quantization errors on hybrid phased-array reflector antennas

The paper examines the influence of array feed error sources, including those due to element truncation, phase quantization, and amplitude quantization for an example reflector with a width of 250 lambda at a scan angle of 5 deg. The peak sidelobe level and rms sidelobe level were used as the figures of merit. Three-bit phase shifters were found adequate to achieve rms sidelobes of -50 dB with feed element amplitude (power) quantization errors as high as 6 dB; rms sidelobes of -60 dB can be achieved by using four-bit phase shifters. Three-bit phase-shifters are adequate for peak sidelobes down to -20 dB; four-bit phase-shifters are adequate down to -30 dB; and five-bit phase-shifters are adequate to -35 dB.