Substrate Integrated Waveguide Antenna with Slow Wave Effect to Minimize Dimensions

On the basis of a previously developed slow wave substrate integrated waveguide, this study offers a new design, simulation, and measurement results of a circularly polarized square slot antenna backed by cavities (SW-SIW). 11.2 GHz is the intended operating frequency for the planned antenna. The size of the proposed antenna has been reduced to 13% when compared to the reference design and 49% when compared to the traditional SIW version of antenna thanks to the internal metallized via that creates the slow wave effect for the physical separation of the electric and magnetic field in the designed antenna structure. The designed antenna has been tested and simulated, and the results show that it performs better than expected in terms of gain, radiation loss, and return loss. According to the suggested design, the maximum return loss achieved by the proposed antenna is 37 dB at 11.2 GHz frequency, and the return loss is less than 10 dB in the frequency range of 11 to 11.3 GHz. With proposed antenna we got the gain of 5.9 dB as compare to reference antenna with 4.8 dBi of gain.