Highly radiative symmetric plasmonic leaky wave antenna

A leaky wave antenna is proposed and designed based on the spoof surface plasmon (SSP) modes with high radiation conversion within the entire operation bandwidth of 12-23 GHz. The conventional LWAs suffer from complexity of the design and low radiation at their higher edge frequencies. Here, a new method is proposed to design the LWAs using symmetric spoof surface plasmon structures. Operating at non-transmission frequency range, the SSP modes ensure the low transmitted power through the LWA and consequently do not require any loading termination. As a result, the design achieves the high radiation efficiency without any loading loss. Benefiting from a simple and single-layer configuration, the symmetric plasmonic LWA generates high efficient backward, broadside and forward radiation with consistent performance through the entire frequency range. The design is experimentally evaluated and demonstrates its performance as a frequency beam scanning antenna.