SIW Diplexer Integrated with Microstrip Antenna

In this paper a new design of multilayer SIW diplexer integrated with microstrip antenna is presented. The design process started with the network synthesis of the SIW diplexer integrated with patch antenna using lumped lowpass prototype networks. The circular cavity structure using TM
₀₁₀
mode is employed in the design of the diplexer and TM
₁₁₀
mode for the antenna. To prove the design concept, modes in the SIW diplexer and in the microstrip antenna are coupled by capacitive circular aperture at the common ground plane. The proposed design is fabricated with standard printed circuit board technology and will be operating at 2.2 GHz and 2.4 GHz each suitable for LTE/WiFi applications. The performance of the proposed design are verified through both simulation and measurement. The measured results are in good agreement with simulated results.