Periodic Ridged Leaky-Wave Antenna Design Based on SIW Technology

A periodic long slot leaky-wave antenna (LWA) based on a ridged substrate integrated waveguide (RSIW) is proposed. To reduce the cross polarization, the long slot is placed on the SIW centerline, and a sinusoidal ridge is used to produce a controllable asymmetric electric field around the long slot. Also, only a small stopband occurs when the beam is scanned through the broadside. Varying the amplitude and width of the sinusoidal ridge provides a fixed phase constant and controllable leakage rate to achieve the desired sidelobe level of less than -30 dB. Measurement results are consistent with the simulation results.