A Compact, Low-loss and High Passband Ratio Substrate Integrated Waveguide Triplexer using Complementary Split Ring Resonators

This paper presents a design of a compact, low- loss and high passband ratio substrate integrated waveguide (SIW) triplexer based on the Complementary Split Ring Resonator (CSRR) structure. The proposed triplexer operates at three passbands of 6 GHz, 8 GHz and 10 GHz that correspond to the passband ratios of 1.33 and 1.67. By appropriately designing square CSRRs on the surface of the SIW, the low-loss and compact passband resonators below the cut-off frequency of the SIW at each operation frequency can be realized. The proposed triplexer is designed on the cost-effective RO4003C substrate. The simulated results show insertion losses are 0.9 dB, 1.02 dB and 1.04 dB at 6 GHz, 8 GHz and 10 GHz bands, respectively. The triplexer occupies just an area of 32.5times 23.5 mathrmmm2. The triplexer is designed using Keysight ADS and CST Microwave Studio simulators. © 2023 IEEE.