Compact 2-D SIW Leaky-Wave Antenna Based on Double T-Junction Impedance Matching for High-Gain Broadside Radiation

This letter presents a novel compact 2-D substrate integrated waveguide (SIW) leaky-wave antenna (LWA) array design for high-gain broadside radiation. By connecting a 1-D transverse-slot SIW LWA with plenty of double T-Junctions to equal longitudinal-slot SIW cavities, a compact 2-D SIW LWA array is constituted and excited by a simple microstrip line. The dispersion features of the 2-D SIW LWAs are theoretically explored using an equivalent circuit model, which shows a reasonable agreement with the full-wave simulation. A 7 × 6 SIW leaky-wave array prototype is designed, fabricated and measured for verification. The prototype features the broadside gain of 19.6 dBi and the aperture efficiency of 80%, which proves the effectiveness of the proposed method.