Full‐Space Scanning Leaky‐Wave Antenna Utilising Spoof Surface Plasmon Polaritons

ABSTRACT A novel spoof surface plasmon polariton leaky‐wave antenna (SSPP‐LWA) capable of full‐space beam scanning is proposed in this letter. First, the surface plasmon polariton (SPPs) unit and its corresponding transmission line are carefully designed, and the underlying mechanism to achieve full‐space scanning is analysed based on a monopole array structure. Specifically, a spoof surface plasmon polariton (SSPP) transmission line combined with a semicircular, three‐dimensionally loaded radiating patch is introduced and equivalently modelled as a monopole radiating element. Subsequently, the proposed LWA is realised by employing a monopole array composed of 12 identical radiating elements. Simulation results verify that the antenna achieves continuous beam scanning from ‐90° to +90° within the frequency range of 9.8–13.3 GHz, exhibiting a high scanning rate of up to 5.94°/%, with an average gain of approximately 9 dBi. Benefiting from its excellent scanning capability and stable radiation characteristics, this antenna demonstrates significant potential for target detection and tracking applications in radar systems.