17.2 A 28GHz magnetic-free non-reciprocal passive CMOS circulator based on spatio-temporal conductance modulation

A significant challenge for silicon-based mm-wave systems is a low-loss shared-antenna (ANT) interface with high linearity, isolation (ISO) and bandwidth (BW). Shared ANT interfaces with simultaneous transmit and receive capability are critical for mm-wave 5G base stations that need to simultaneously communicate with multiple users, FMCW-based radars, and emerging full-duplex systems [1].