Design strategies for metamaterial quadrature power dividers in CP antennas: Are two CRLH-loaded lines necessary?

Abstract

Integrating composite right/left-handed (CRLH) transmission lines into quadrature power dividers (QPDs) has demonstrated potential for enhanced bandwidth in circularly-polarized antenna applications. Despite the excitement about CRLH, optimal design strategies remain ambiguous, and previous work proposed varied embodiments of CRLH integrations but do not direct designers towards optimal designs strategies for QPDs. This paper investigates the necessity to integrate CRLH in both output paths of QPDs versus one output path. Our analysis reveals that there is no advantage from a dispersion perspective. Both analytical models and simulations agree with this conclusion, encouraging future users of this concept to employ a single CRLH line approach.