We examine recent results on measurements of the magnetic penetration depth in cuprate superconductors, with particular emphasis on our results obtained with the microstrip and parallel-plate resonator techniques. The results show that the magnetic penetration depth temperature dependence in YBa2Cu307-a is not consistent with a simple scaled weak-coupled BCS temperature dependence. We present t...

A novel technique fitr the bat dividth enhancement of conventional rectangular microstrip antenna is proposed in this paper. When a high permittivity dielectric resonator of suitable resonant frequency was loaded over the patch. the % bandwidth of the antenna was increased by more than five tunes without much affecting its gain and radiation performance. A much more improved bandwidth was obtai...

The embedded meander line in stepped-impedance resonator (SIR) is proposed to design narrow bandpass filter with a good stopband characteristics. The design differs from the general SIR configuration in that the microstrip lines are bent at the location of the maximum magnetic field density. As a result, the resonators have high external quality factors by themselves, since the factor is closel...

A geometrically symmetrical fractal structure is presented in this paper to provide an alternative approach for the miniaturization design of microstrip bandpass filters (BPFs). The generation process of the geometric geometry is described in detail, and a new fractal resonator called Greek-cross fractal resonator (GCFR) is produced by etching the proposed fractal configuration on the surface o...

A new microstrip ultra-wideband (UWB) bandpass filter (BPF) with triple-notched bands is presented in this paper. The circuit topology and its corresponding electrical parameters of the initial microstrip UWB BPF are desired by a variation of genetic algorithm (VGA). Then, triple-notched bands inside the UWB passband are implemented by coupling a square ring short stub loaded resonator (SRSSLR)...

We numerically demonstrate that spoof localized surface plasmons (LSPs) resonant modes can be enhanced based on ultrathin corrugated metal-insulator-metal (MIM) ring resonator. Further enhancement of the LSPs modes has been achieved by incorporating an efficient and ease-of-integration exciting method. Quality factors of resonance peaks have become much larger and multipolar resonances modes ca...

─ A simple and novel low-loss diplexer with two folded Open-Loop Ring Resonators (OLRRs) that couple three microstrip lines is proposed. The first passband and second passband of the designed diplexer could be easily and accurately shifted to a desired frequency and construct the bandpass filters by adjusting the physical dimensions of the OLRRs. These results suggested that the proposed diplex...

At frequencies currently used by mobile communications, many of the microstrip half-wavelength resonators are too large to realize miniaturized filters. For this reason, very small-sized microstrip spiral resonators and filters, using high-temperature superconductors (HTS), have been studied recently. In this paper, the resonant and coupling characteristics of microstrip G-type and S-type spira...

This paper describes the design and simulation of the new Ɛ negative metamaterial unit cell structure and then the unit cells are combined to form 3D array which use as metamaterial cover with a single microstrip patch antenna. The new Ɛ negative metamaterial is based on the ELC resonator structure, which is used for obtaining the negative value of permittivity and positive value of permeabilit...

A miniaturized self-matched negative group delay (NGD) microwave circuit without the need for external matching networks is proposed. The NGD circuit is based on a modified parallel-type RLC resonator, in which lumped elements (capacitors and inductors) are implemented by microstrip gaps and high-impedance and short-circuited microstrip lines. To verify the design concept, an NGD circuit with t...