A GaN HEMT 6-Bit Digital Phase Shifter for Millimeter Wave Phased Array System

Abstract

This paper presents a 6-bit digital phase shifter (PS) using a 100nm GaN high electron mobility transistor process for millimeter wave phased array systems. The PS combines a 2-bit switched L/C structure, a 2-bit T-type topology, and a 2-bit high-pass/low-pass network, with cascading order optimized to minimize the phase and amplitude deviations. The electromagnetic simulation results for the PS indicate that the insertion loss is less than 10.4 dB, the rms phase error is less than 3.7°, the rms amplitude error is less than 1.3 dB, and the input/output return loss is better than 9.1 dB in the operating frequency of 24–30 GHz. The size area of the presented PS is 2.8 × 0.9 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> .