Dual-Band Reconfigurable Impedance Matching Networks

This article presents a novel methodology for designing Dual-band Reconfigurable Impedance Matching Networks (Db-RIMNs) using a cascade network of tunable filters and phase shifters. The proposed design can be used to match frequency dependent and impedance variable dual-band loads. The theory of operation, the design considerations, and the design procedure are provided. Moreover, a prototype circuit is designed for a dual-band variable load at sub-6 GHz bands. The performance of the proposed design is not restricted by the range of realizable characteristic impedances. Moreover, the achievable impedance coverage and frequency ratio of the two bands are not restricted by the circuit fabrication limitations. Finally, the performance in terms of matched bandwidth and losses are investigated. The simulation and measurement results for a fabricated prototype are in close agreement. The proposed design has a wide range of anticipated applications in design of concurrent dual band power amplifiers, multiband antennas, phased arrays, to name a few. The cascade architecture of tunable filters and phase shifters is the sole published design for Db-RIMNs in the literature.