Mixed-mode characterization of a circularly-polarized CRLH leaky-wave antenna

In this work, the mixed-mode approach is employed to characterize the modal parameters of a newly-invented circularly-polarized (CP) composite right/left-handed (CRLH) leaky-wave antenna (LWA). The single-ended CP-LWA is comprised of two coupled CRLH LWAs, which operate as a balanced structure supporting simultaneously common and differential mode excitations resulting in orthogonal current distributions, and a balun-like structure which induces the dual excitations with a phase-quadrature between them. The mixed-mode approach is advantageous over traditional approaches using either baluns or external probes due to its simplicity, efficiency, low cost and wide frequency response. Using full-wave simulation results of the CP-LWA, the modal parameters from the mixed-mode approach efficiently identified performance limitations for the CP-LWA.