A Highly Reconfigurable Leaky-Wave Antenna Based on Multimode Spoof Surface Plasmon Polaritons

This letter presents a periodically modulated reconfigurable leaky-wave antenna (R-LWA) based on multimode spoof surface plasmon polaritons (SSPPs) with a simple dc bias scheme, featuring high reconfigurability in operating frequencies, bandwidth, and beam direction. The radiation is generated through the periodic modulation of two SSPP units supporting different modes: the 1st SSPP mode in conventional units and the 2nd SSPP mode in CSRR-loaded units. The operating band lies between the high-frequency cutoff of the 1st mode and the low-frequency rejection of the 2nd mode. With varactor diodes as tunable elements, the cutoff frequencies and dispersion of the two SSPPs modes can be individually and instantaneously adjusted, enabling real-time reconfiguration of the antenna operating frequencies and bandwidth. Moreover, an 85° fixed-frequency beam scanning range can also be achieved accordingly.