Design of 28GHz CMOS phased array T/R circuits for 3-dimensional beamforming applications

A 28GHz CMOS phased array T/R circuit is designed for 3-dimensional beamforming system in 5G millimeter-wave communication applications. The T/R circuit integrates a phase shifter, a digital step attenuator and a SP8T switch. It provides 64-state attenuations in 0.5dB step via 6-bit attenuator circuit, and 32-state phase shifts in 11.25° step via 5-bit phase shift circuit, and overall a 14dB insertion loss, 7.6dBm input-referred P1dB.