Compact Analog All-Pass Phase-Shifter in 65-nm CMOS for 24/28 GHz on-Chip-and in-Package Phased-Array Antenna

This paper describes the synthesis method and implementation in 65-nm CMOS technology of a compact analog phase-shifter (PS) dedicated to 24/28 GHz applications. This PS delivers a phase shift continuously tunable from 0 to 55° and is particularly suited for on-chip or in-package phased-array antenna. The proposed topology, which is based on an all-pass circuit that includes coupled microstrip lines and varactors as tunable components is intrinsically compact and shows an interesting phase-range vs capacitance-variation ratio.