Design of a 17–22 GHz 5-bit CMOS vector-sum phase shifter for SATCOM receivers

This paper presents a CMOS vector-sum phase shifter for SATCOM-on-the-move receiver front-ends in hybrid phased-array antennas. The proposed circuit is an active, digitally programmable 5-bit phase shifter composed of two variable-gain amplifiers (VGAs) followed by an active power combiner. A key feature of the proposal is the use of dummy transistor arrays to keep the input and output impedances constant across the different gain states, which helps preserve phase and gain accuracy. Implemented in 65-nm CMOS technology, the phase shifter achieves RMS phase and gain errors below 3° and 0.4 dB, respectively, over the 17–22 GHz frequency range. In comparison with previously reported active phase shifters operating in similar frequency ranges, the proposed design exhibits a competitive trade-off among phase accuracy, gain variation, bandwidth, and power consumption.