<i>X</i>-Band Quasi-Elliptic Non-Reciprocal Bandpass Filters (NBPFs)

This article reports on the design and practical development of RF co-designed MMIC components that exhibit function a bandpass filter an isolator. They are based cascaded non-reciprocal frequency-selective stages (NFSs), one-pole/two-transmission zero (TZ) multi-resonant stages, impedance inverters. The combination these results in two-port network exhibits nonreciprocal quasi-elliptic (NBPF) response forward direction full signal cancellation reverse one. operating principles NBPF presented through various circuit-based examples low- high-order configurations. For proof-of-concept demonstration purposes, prototypes were designed GaAs process experimentally validated at X-band. include two-pole/two-TZ three-pole/four-TZ NBPF.