A Simultaneous Phase Shifter and Up-Converter for the 28/38/60-GHz Bands in 28-nm CMOS

This paper presents a novel millimeter-wave vector modulator that exploits multi-band beamforming at the mixer level. By adding a compact quadrature coupler, single-pole double-throw (SPDT) switches and a pair of independent variable-gm stages to a Gilbert cell type mixer, simultaneous up-conversion and phase shifting in a 0-360° range can be achieved. The circuit is implemented using a 28-nm bulk CMOS process. It allows tri-band operation at the 28, 38 and 60-GHz mm-Wave bands, showing a measured peak conversion gain of -12, -13 and -16 dB, respectively. It consumes 10.8 mW from a 1.2-V supply and occupies 0.11 mm2 without pads.