Wideband 5-bit Vector-sum Phase Shifter for 5G Millimeter-wave Applications

This paper presents a wideband 5-bit vector-sum phase shifter implemented in a low-cost 90-nm CMOS process. The proposed vector-sum phase shifter consists of a wideband quadrature generator with low amplitude/phase imbalance and a wideband, low-phase variation variable-gain amplifier integrated with 0/π phase shifter to satisfy most of the operation frequency bands of the 5G millimeter-wave communications. From 25 to 43 GHz, the proposed 5-bit phase shifter demonstrates the RMS amplitude/phase errors of better than 1.4 dB/4.8°, and the insertion losses of all states are lower than 6.4 dB from 25 to 43 GHz.