High-Scanning-Rate and Wide-Scanning-Angle Spoof Surface Plasmon Polaritons Leaky-Wave Antenna with Open-Stopband Suppression

In this communication, a leaky-wave antenna (LWA) based on spoof surface plasmon polaritons (SSPPs), showing high scanning rate, wide scanning angle and open-stopband (OSB) suppression is studied. This design presents a general technique to independently control cut-off frequency and slope of the dispersive curves of single-layer SSPPs units by manipulating the longest and shortest current path length respectively. The radiation of LWA is realized by sinusoidally modulated reactance surface (SMRS). By unifying cut-off frequency and modulating slope of “cross-shaped” SSPPs units in the design, the slot length modulation is introduced instead of the classical groove depth modulation which makes full use of unit slow-wave property under the condition of realizing reasonable radiation, thus realizing high scanning rate. Furthermore, the design presents a novel asymmetric modulated equation to suppress OSB by combining two half-period SMRS structures with different unit numbers and changed lengths in SMRS LWAs to introduce appropriate transverse asymmetry. The detailed realization process is illustrated step by step in this communication. A prototype of LWA is fabricated and measured, presenting a continuous beam scanning from −65° to 68° in a frequency band of 10.6 GHz to 12.7 GHz.