Patent ID: 8072291
Filing Date: 2011-12-06
Classification: H01P

Abstract:
1. An apparatus, comprising: a ring of composite right/left-handed (CRLH) transmission line (TL) material having both right handed (RH) and left handed (LH) characteristics; a plurality of lumped elements comprising inductances and capacitances within said LH portions of said CRLH TL; and a plurality of ports, including a sum port and a difference port, on said ring separated along a periphery of said ring by either phase delays φ wherein dual frequency characteristics of each segment of said CRLH TL arise in response to an anti-parallel relationship between phase and group velocities below a transition frequency ω wherein said ring is compacted into a compact ring in response to constraining phase delay contributions to |φ wherein said LH portion further comprises stepped impedance sections in the TL segment corresponding to phase φ