Backward to Forward Beam Scanning Leaky-Wave Antenna Base on Corrugated Substrate Integrated Waveguide

A Corrugated Substrate Integrated Waveguide (CSIW) with rectangle ring slot is proposed and designed for leaky wave antennas (LWA) capable of beam scanning from backward to forward directions. The rectangular ring slot does not only enable the energy leaking, but also provides serial capacitance. In addition, the grounded vias and quarter-wave open-circuit stubs provide shunt inductance. Thus, the proposed CSIW exhibits lefthanded characteristics which enable beam scanning through the broadside. To suppress the stop-band, an equivalent circuit model is developed. Finally, a balanced leaky wave antenna is designed with a radiation angle from −53° to 23° with the frequency ranging from 9.8 GHz to 12 GHz, and the gain is better than 8.5 dB and the maximum gain achieves 10.7 dB.