Microwave amplifier with substrate integrated waveguide bandpass filter matching network

This letter presents a microwave amplifier (MA) with a substrate integrated waveguide (SIW) bandpass filter (BPF) output matching network (OMN). The codesigned amplifier and SIW BPF with complex termination impedance (CTI) can reduce the circuit size and the design complexity while improving loss. To match the CTI of the SIW BPF, the frequencies of the first and/or last resonators must be detuned. Moreover, the proposed SIW BPF OMN can be designed for Chebyshev characteristics in either odd- or even-ordered resonators. For validation, the MA with the proposed SIW BPF OMN was designed at 10 GHz. High-frequency selectivity is obtained by using the proposed SIW BPF OMN along with conventional MA performances.