Tunable Phase Shifter with Large Phase Range Based on Reconfigurable Resonator

A novel tunable phase shifter (PS) with large phase range is proposed based on the reconfigurable resonator. The PS composes of one switchable resonator with compact size and two external coupling networks (ECNs). The resonator is designed to switch between two states with a large constant phase difference and with different matching impedances. The ECNs are used to match the changeable impedance and meanwhile shift the phase continuously. The switchable resonator cooperates with the ECNs to complete the entire PS design, doubling the phase shift range (PSR) to 180°. The systematic design method taking phase performance into consideration is put forward. The designed PS exhibits good performance with 10-dB fractional bandwidth of 13.3%, a large PSR of 0° - 180°, and a low phase error of ± 3.5°.

I. Introduction

Phase shifters (PSs) are the fundamental building blocks in the modern phased arrays for beam scanning and shaping functionalities. PS with large phase shift range (PSR) and low phase error is highly desirable to meet the requirements of wide scanning range and precise radiation pattern [1]–[2].