A 57-to-64 GHz Ultra-Compact 0.027 mm2 Reflection Type Phase Shifter with Low Insertion Loss

An ultra-compact reflection-type phase shifter (RTPS) with more than 190 degrees continuous phase shift and low insertion loss using 90-nm CMOS process is demonstrated in this paper. Two circuit implementation techniques are employed: LC-type reflection loads with switches and 3-dB quadrature coupler. First, the LC-type reflection loads with switches have been proposed to alleviate the issue of quality factor. Second, the 3-dB quadrature coupler is designed with broadside couple to reduce chip size and enhance couple factor. Measurements show signal losses of 9.3dB +/- 1.5dB including pad loss, loss flatness of +/- 0.9 dB, and a more than 190 degrees continuously tunable range across 57-64 GHz with 0-mW dc power consumption. To the best of our knowledge, the proposed phase shifter has the smallest die size of 0.027 mm(2), among all reported V-band CMOS phase shifter, which is important for a multi-way phased-array system.