A Miniaturized Broadband 1 × 4 Filtering Butler Matrix With 360° Continuous Progressive Phase Shift and Simplified Control - Wei, Liu-Yu; Chen, Fu-Chang; Wang, Xi-Zhu (IEEE transactions on microwave theory and techniques, 2025)
Keywords: Broadband; Broadband antennas; Broadband communication; Butler matrices; Butler matrix (BM); compact size; continuous tunability; Coplanar waveguides; Couplers; Filtering; filtering phase shifter (FPS); Filtration; Frequency response; Microwave filters; Modules; Phase shift; Phase shifters; single layer; Switches; Topology; Transmission lines; Wireless communication