Signal-interference microstrip duplexers

Microwave planar duplexers shaped by signal-interference bandpass filters in their branches are presented. To produce spectral asymmetry in the transfer functions of these filters for channel isolation, stepped-impedance lines are embodied in their building transversal filtering sections. Two examples of microstrip duplexing devices, each of them based on a different type of transversal section, are designed. Simulation results for both circuits and measurements for a manufactured proof-of-concept prototype are also provided.