A miniaturized CRLH based SIW leaky-wave antenna for continuous backward-to-forward fast beam scanning with low side lobe levels

In this study, a substrate-integrated waveguide (SIW)-based miniaturized leaky-wave antenna (LWA) with fast beam scanning is proposed. The proposed LWA exhibits composite right/left-handed (CRLH) property and its unit cell consist of an inverted Z-shaped slot etched on the top layer of SIW. By sweeping frequency from 9.4 to 11.4 GHz, the proposed CRLH LWA can steer the frequency beam continuously from -40 degrees to 51 degrees, which shows fast beam scanning within the impedance bandwidth (2 GHz) of LWA. The good leakage constant contributes to the miniaturization of the LWA with electrical dimensions of 3.38 lambda(0) x 0.34 lambda(0) mm(2). The antenna attains a peak gain of 12.5 dBi with maximum radiation efficiency of 92%. The antenna attains low sidelobe levels below 12 dB; the low sidelobe levels in the LWA are obtained by creating symmetricity in the unit cell around the centerline. The designed LWA is a viable contender for X-band beam scanning applications.