Enhancing Load Range Of Concurrent Dual-Band Complex To Real Matching Networks Using Load Shifters

Abstract

This paper presents enhancement of the load range of dual band matching networks (DBMNs) for complex to real (C2R) impedance matching through load shifters. The proposed load shifter is a simple structure and has versatility to serve any impedance environment for any frequency ratio. In this paper, the limitations of a single section transmission line used for transforming frequency dependent complex loads (FDCLs) to complex conjugate loads (CCLs) in many earlier reported DBMNs has been discussed. The possible range of loads at one frequency if the load at other frequency is given is thoroughly studied. A load shifting approach for shifting the loads to the values such that FDCLs can be transformed to CCLs is proposed. Two prototype MNs with frequency ratios 1.6 and 5.6 respectively wherein the proposed load shifters are successfully applied are designed, simulated and fabricated. The simulated and the measured results are in a good accordance. This scheme can also be used with any other regular DBMN having load constraints.