Design of a Fully Reconfigurable Multifunctional Non-Reciprocal Quise Reflection-Less Interdigital BPF

Abstract

This  paper presents the design, simulation, and measurement of a multifunctional nonreciprocal quasi-reflectionless bandpass filter. Initially, we designed a conventional 5-pole interdigital bandpass filter (BPF). Subsequently, a suitable absorptive component is attached to the conventional interdigital BPF in order to absorb any reflected signals, resulting in the formation of a quasi-reflectionless BPF. One can turn a normal bandpass filter (BPF) into a nonreciprocal BPF by employing the Spatial Temporal Modulation (STM) . In order to obtain a multifunctional bandpass filter, all of these features must be combined into a single filter. Therefore, pin diodes can operate as switches to control the response of multifunctional bandpass filters. The proposed filter can provide multiple response states, including reflective bandpass filters, quasi-reflectionless bandpass filters (with one port and two ports), non-reciprocal bandpass filters, and non-reciprocal quasi-reflectionless bandpass filters. The filter was designed using a Fr4 substrate and a CNC machine. The measured results demonstrate a high level of agreement with the simulated results.