A Low Loss Patch-Based Phase Shifter Based on SISL Platform

This paper proposes a low loss patch-based phase shifter based on substrate integrated suspended line (SISL) platform. Two patches are used for generating the required phase difference for the first time. As a demonstration case, a 45 degree phase shifter is implemented and fabricated by using standard printed circuit board (PCB) process. From 23 GHz to 28 GHz, the measured phase error is within 2°. Embedded inside the SISL air cavity, the patch-based phase shifter has very low insertion loss of 0.3 dB, which is much smaller than previous designs. Moreover, the proposed SISL patch-based phase shifter has advantages of low cost, light weight, and self-packaging.