Asymmetric Stub loaded HMSIW Leaky-Wave Antenna for Continuous Scanning through Broadside

In this work, a half-mode substrate integrated waveguide (HMSIW) leaky-wave antenna loaded with asymmetric stubs is proposed to suppress the open stopband (OSB) effect to achieve continuous scanning through broadside. To achieve this, two rectangular portions are etched out from the diagonally opposite corners of the conventional rectangular stub, thereby introducing the desired asymmetry. The HMSIW’s width, periodicity, and stub length are systematically optimized to attain the desired broadside frequency. To verify the simulation results, prototype of the proposed design is fabricated and the antenna parameters are measured. The antenna exhibits efficient broadside radiation with a maximum gain of 14.8 dBi at 10 GHz.