Single-Side-Scanning Surface Waveguide Leaky-Wave Antenna Using Spoof Surface Plasmon Excitation

A surface waveguide (SWG) leaky-wave antenna featuring directional single-side beam scanning capability is presented. A novelty of the design is that transition design utilizes the spoof surface plasmon (SSP) as an intermedia to feed the SWG, which realizes an efficient SWG transition from the conventional coplanar waveguide. In addition, a novel spatial profile is modulated on the SWG to produce leaky-wave radiation. Because the transmission modes in SSP and SWG are similar, the transition exhibits low loss and broadband performance. Both the transition and the leaky-wave antenna are demonstrated using simulations and experiments. It is shown that the transition has an average loss of 0.61 dB across the frequency range 5-13 GHz, which is an improvement on other feeding techniques reported. It is also shown that the leaky-wave antenna produces a single-side scanning beam of 8.7 dB gain with an overall efficiency of 75%. The beam scans through a 43.5-degree range over the frequency 10-13 GHz.