A Compact Full-Space Scanning Leaky-Wave Antenna With Stable Peak Gain

A full-space scanning leaky-wave antenna featuring small aperture size and relatively stable gain is proposed in this communication. We propose three key conditions for full-space scanning capability, including single-harmonic radiation, field cancellation suppression at endfire, and open stopband suppression at broadside. Results from a prototype based on paired stubs and crossover offset parallel striplines are provided to verify the proposed principle. Experimental results show that the main beam is able to continuously scan from backfire to endfire with stable gain around 9.1 dBi within the frequency range of 4.5–10.2 GHz. The antenna aperture is
$6.85\lambda _{0}\times 0.1\lambda _{0}$
only.