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° 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° 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 mm², among all reported V-band CMOS phase shifter, which is important for a multi-way phased-array system.