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The theoretical study and experimental results of a compact tunable left-handed (LH) zeroth order metamaterial ferrite resonator is presented. The resonator has been designed and realised using a LH coplanar waveguide transmission line on a ferrite substrate. The theoretical analysis of the operation principles of the resonator has been provided. The detailed measurement setup and experimental results are discussed. The resonator is only 0.19 λg (65% reduced in size comparing with conventional one) at 4 GHz. The resonator has fractional bandwidth of 0.1% and average insertion loss, approximately 4.5 dB. Moreover, the zeroth order metamaterial ferrite resonator has tuning capability and requires lower DC magnetic bias. [ABSTRACT FROM AUTHOR]

In this study, the authors present a novel compact non-reciprocal ferrite forward composite right-/left-handed (CRLH) coupled-line coupler (CLC). The proposed forward coupler is realised in coplanar waveguide configuration using series air gap capacitors and shunt planar segment inductors. A theoretical coupled mode analysis of a general non-ferrite CRLH forward CLC has been proposed. The mode analysis is then extended to ferrite CRLH forward CLC. The ferrite coupler's performance has been further analysed numerically and verified experimentally. Both numerical and experimental results have shown that the coupler demonstrates non-reciprocal operation for both forward coupling and through propagations. The coupler can achieve ~10 dB forward coupling and through levels with nonreciprocity isolation up to 30 dB. Moreover, the coupler has high backward coupling isolation better than 20 dB and very compact size with coupling length = 0.08 λ0 or (0.2 λg) at 8 GHz which is significantly smaller compared with any forward coupler reported to date in the similar operating frequency bands. Although, a conventional ferrite forward CLC can be non-reciprocal, it has long length, resulting in very high losses. This is not the case for the proposed CRLH coupler. Hence, the novelty and advantage of the coupler are its combined properties in compactness and nonreciprocity. Furthermore, the coupler requires very low external DC magnetic bias because of its much lower demagnetisation compared with the microstrip configuration. [ABSTRACT FROM AUTHOR]

A fully integrated broadband coplanar waveguide left-handed metamaterial medium using GaAs technology for radio frequency/monolithic microwave integrated circuit (RF/MMIC) applications is reported and validated by the full wave simulation and measured results. The unit cell of the fabricated structures has a size of 0.09 mm2. The left handedness of the integrated left-handed structure extends from 2.3 to 17.5 GHz. The compactness and broad left-handed operating bandwidth make the presented left-handed metamaterial be well incorporated with RF/MMIC applications. [ABSTRACT FROM PUBLISHER]

This letter explores the dc isolation and radio frequency (RF) dissipation loss of coplanar waveguide (CPW) lines of H+ and Fe+ ion bombarded GaAs multi conductive epitaxial layers. It is demonstrated that although a sheet resistivity as high as 108 Ωsq has been achieved by ion bombardment, showing excellent dc isolation, the RF dissipation loss of gold metallized CPW lines on the bombarded multi conductive epitaxial layers are higher than that on a semi-insulating GaAs substrate, especially at higher frequencies (0.5 dB/cm higher at 50 GHz). This is probably caused by deep level trappings due to the ion bombardment. [ABSTRACT FROM PUBLISHER]