Design of New Eight-Channel Diplexer for Multiband Wireless Communication System

In this paper, we proposed a new eight-channel diplexer (1.575/2.4/3.5/5.2 and 1.8/2.6/4.2/5.7 GHz) with a simple source-load input/output structure containing four pairs of coupled asymmetric stepped-impedance resonators (SIRs) in a compact circuit size. By tuning the impedance ratio and the length ratio of the asymmetric SIRs, each resonant mode can be easily determined, and the diplexer with close quad-passbands (quad-channels) can be implemented. The new eight-channel diplexer for multiband wireless communication systems including of global positioning system, global system for mobile communications, Wi-Fi, and 5G mid-band.