57-67-GHz Highly Compact Bidirectional 3-Bit Phase Shifter in 28-nm CMOS

This letter describes a highly compact, low-loss, high-bandwidth, bidirectional, passive 3-bit phase shifter (PS) implementation for 5G and WiGig applications at 57-67 GHz, fabricated in Taiwan Semiconductor Manufacturing Company 28-nm CMOS technology. First, a highly compact, differential quadrature hybrid coupler is used for the I/Q generation. Consuming only 0.006 mm(2), it achieves 4.5-dB insertion loss (IL) with less than 1-dB amplitude imbalance, and 6 degrees I/Q phase imbalance, for the entire frequency band. The hybrid coupler is followed by a novel compact transistors switching matrix to create the 3-bit, bidirectional, 360 degrees PS, which provides impedance matching for all states. It consumes the smallest ever reported PS chip area of only 0.007 mm(2) with state-of-the-art results of the maximum rms phase and gain errors of 6.3 degrees and 0.94 dB, respectively. The measured IL was 10.8 dB between 57 and 67 GHz.