Low RMS phase error 28 GHz 5-bit switch type phase shifter for 5G applications

A 28 GHz 5-bit switch-type phase shifter (STPS) using 0.18 μm CMOS technology is presented for 5G mobile communication applications. Utilising a process variation insensitive transmission line-based bridged T-type topology for 11.25°, 22.5°, 45°, 90°1-bit phase shifters and high-pass/low-pass network switched-path-type topology for 180°1-bit phase shifter, the 5-bit STPS achieves ultra-low root mean square (RMS) phase error of 1.7°and low RMS amplitude error of 0.59 dB at 28 GHz with intrinsic digital phase-control mechanism. The measured insertion loss of all 32 states is 15 ± 1.5 dB at 28 GHz with zero dc consumption.