Microwave Substrate Integrated Waveguide Power Amplifier using Complementary Split Ring Resonators

This paper proposes a substrate integrated waveguide (SIW) power amplifier (PA). By using the SIW technology, the PA has advantages of low radiation loss and high capability of integration with other planar components on the same substrate. In this paper, a new configuration of resonator is used in input/output matching circuit, which is complementary split ring resonator (CSRR). The CSRR has benefits of high selectivity, compact size, and feasibility for etching on the SIW. The method of designing the SIW matching circuit is that the resonant frequency of the first/last resonator is detuned to transform a real impedance of 50 Ω to a complex impedance. The cosimulation results show that the SIW PA achieves a maximum power added efficiency (PAE) of 57.05%, an output power $P_{\mathrm{out}}$ of 37.43 dBm, and a power gain G of 13.43 dB at 6 GHz.