Abstract:With the scanning rate of traditional spoof surface plasmon polaritons (SSPPs) leaky-wave antenna being low, a novel double layer SSPPs element is proposed, and a leaky-wave antenna with high scanning rate is realized on the basis of this. The proposed double layer SSPPs element consists of a top SSPPs element with a “H” cell and a bottom SSPPs element with a “I” element. The proposed element is characterized by independently controlling the cut-off frequency and slope of the dispersion curve, realizing the cut-off frequency and slope of dispersion curve to be controlled independently by controlling the dispersion property of the top and bottom SSPPs elements respectively. The radiation of the proposed leaky\|wave antenna is realized by sinusoidal surface impedance modulation of the “H” elements on the top layer. Due to the existence of the bottom “I” SSPPs elements, the strong dispersion property is introduced to improve the growth rate of period phase shift, thus achieving the high scanning rate. In addition, the open stopband (OSB) phenomenon of the leaky-wave antenna is almost completely suppressed by introducing short open-ended stubs in the periodic radiation structure. The prototype of the proposed leaky-wave antenna is simulated, machined and measured. The leaky-wave antenna is capable of achieving continuous wide-angle scanning from -63° to 63° at a narrow band between 8.8 GHz and 10.8 GHz. The consistency between the experimental and the simulated results proves the correctness of the proposed double-layer SSPPs element and the design theory.