A Novel and Simplified Topology for Vector-Sum Phase Shifters

In this paper, we present a novel and simplified topology for a vector-sum phase shifter. The proposed topology leverages only two biphase modulators (based on 90° and 180° hybrid couplers), Wilkinson power dividers, and variable gain components. The biphase modulators generate the necessary quadrature vectors (±I, ±Q) for vector synthesis. To demonstrate the effectiveness of the proposed approach, a passive Kaband four-bit vector-sum phase shifter was designed using PCB technology. The EM simulation results exhibit a return loss of less than 10 dB across the bandwidth from 36 GHz to 44 GHz for all phase shifts, a phase shift range of 360°, and RMS phase and amplitude errors of 1.9° and 4.4 dB, respectively, at 39 GHz. The average insertion loss (IL) was simulated to be 19.5 dB. Despite its simplicity, the phase shifter structure achieves excellent phase performance, showcasing its potential in practical applications.