Dual-Band Leaky-Wave Radiation Enabled by Field and Dispersion Discontinuities in Dual-Period Modulated Odd-Mode SSPPs

This letter presents a dual-period modulated leaky-wave antenna (LWA) based on odd-mode spoof surface plasmon polariton structures (SSPPs), enabling continuous wide-angle frequency scanning in the higher band and full-space fast beam scanning in the lower band. The dual-band radiation is realized through two leakage mechanisms separated by the higher-band cutoff frequency. Above cutoff, a field-distribution discontinuity perturbs the SSPP mode into a fast-wave leakage. Below cutoff, periodic modulation formed by combining SSPP cells with distinct dispersion slopes excites sub cutoff leakage. In both cases, deliberate structural asymmetry is introduced to suppress the open-stopband. Results confirm wide-angle coverage (-90° to +40°) from 11.5 to 29.0 GHz, alongside full-space scanning (-90° to +90°) from 6.7 to 9.3 GHz. By integrating dual-band operation, stopband suppression, and continuous wide-angle scanning, the proposed design is promising for multi-frequency target acquisition scenarios.