A Wideband Calibration-Free D-Band Passive Phase Shifter With Frequency-Invariant Codes Over 24% Fractional Bandwidth

Abstract

This work presents a compact 110–140 GHz bidirectional D-band passive phase shifter based on combining a 5-stage capacitively-loaded reflective-type PS (RTPS) with a wideband 0°/180° stage. The design achieves a 360° phase range with a resolution of 11.25°. By applying: 1) a wideband RTPS design methodology on the stage level; 2) frequency/switching-staggering techniques among the RTPS stages; and 3) a balun-staggering technique into the 0°/180° stage, the design achieves calibration-free operation with frequency-invariant codes over 24% fractional bandwidth (FBW). The design is implemented in GlobalFoundaries 22-nm CMOS FD-SOI technology with a compact core area of $130~\mu $ m $\times 480~\mu $ m. It achieves measured RMS phase and magnitude errors lower than 2.38° and 0.63 dB, respectively, across the entire operating bandwidth using the same frequency-invariant codes.