A Planar Metamaterial Transmission Line Phase Shifter with Embedded Silver-Coated Ferrite Particles

This article presents designing a novel planar phase shifter working in the C-band (5-6) GHz without any additional voltage biasing circuitry. It is based on a composite right/left-handed (CRLH) structure with additional two symmetric stub lines. Silver-coated ferrite particles are embedded in the cavities drilled in the substrate under stub lines to control the signal phase. A tiny magnet is used to activate the silver-coated particles inside the substrate cavity which in turn controls the signal phase. Unlike the traditional available phase shifters, the proposed phase shifter does not necessities any external DC power. The phase shifter varies the RF signal phase with maximum achieved phase shift of 47.3 degree using single unit and 95.4 degree with cascaded two unit cells. The insertion loss is -1.4 dB which shows excellent signal transmission through the phase shifter. The network analyzer is used to validate the results of both unit cell and two unit cell phase shifters. The measurement results are very close to the simulation results. The novel phase shifter has numerous applications, particularly in the domains of flexible electronics and phased arrays.