摘要

This paper presents the design of a compact 60-GHz phase shifter that provides a 5-bit digital phase control and 360 degrees phase range for beam-forming systems. The phase shifter is designed using the proposed cross-coupled bridged T-type topology and switched-varactor reflective-type topology. The topologies are analyzed using a small-signal equivalent circuit model. Furthermore, the design equations are derived and investigated. To validate the theoretical analysis, 60-GHz 5-bit 360 degrees phase shifters are designed in a commercial 65-nm CMOS technology. The fabricated 360 degrees phase shifter features good performance of 32 phase states from 57 to 64 GHz with an rms phase error of 4.4 degrees, a total insertion loss of 14.3 +/- 2 dB, an rms gain error of 0.5 dB, P-1 dB of better than 9.5 dBm, and the power consumption of almost zero. To the best of our knowledge, the designed 360 degrees phase shifter with the size of 0.094 mm(2) is the smallest 5-bit passive phase shifter at frequencies around 60 GHz.