CRLH CPW Antenna on Magnetically Biased Ferrite Substrate

Abstract

The aim of this paper is to describe the results obtained by experimenting with a Composite Right/Left Handed Co Planar Waveguide (CRLH CPW) zeroth-order resonating antenna on a ferrite substrate magnetically biased with a DC magnetic field. The CRLH structure consists of a series of connected CPW interdigital capacitors and parallel ground connected CPW transmission lines as inductors to form an antenna structure working at the frequency of 13,350 GHz. The ferrite substrate for this antenna has the saturation magnetization of 550 G, the dielectric constant of 13.5 and the resonance linewidth of 16.8 kA/m. If this device is subjected to a magnetic biasing field ranging between 0 T and 0.26 T, modeling demonstrates an antenna frequency tuning of about 450 MHz (meaning ∼ 3.4%) as a result of this magnetic field variation. Also, a scanning of the antenna radiation pattern occurs when the ferrite substrate is magnetically polarized. Data obtained by measurements indicate a deviation of the radiation pattern between +12° and −10° for a variable magnetic biasing field between 0 T and 0.16 T respectively. The originality of this approach consists in highlighting the possibility of changing the working parameters of a ferrite supported antenna by using an external biasing magnetic field. The experiment validates the data obtained by modeling.