Available microwave techniques for crack detection have some challenges, such as design complexity and working at a high frequency. These challenges make the sensing apparatus design complex and relatively very expensive. This paper presents a simple method for surface and subsurface crack detection in metallic and non-metallic materials based on complementary split-ring resonators (CSRRs). A C...

In this paper, we proposed a stretchable radio frequency (RF) sensor to detect strain direction and level. The stretchable sensor is composed of two complementary split ring resonators (CSRR) with microfluidic channels. In order to achieve stretchability, liquid metal (eutectic gallium-indium, EGaIn) and Ecoflex substrate are used. Microfluidic channels are built by Ecoflex elastomer and microf...

We present electrically small, multi-band, metamaterial-inspired antennas with adequate radiation characteristics and isolation enhancement. The antenna element consists of a complementary split-ring resonator (CSRR) embedded in small monopole that has size λ/8 × λ/10 at the lowest frequency band, while rectangular patches are placed underneath it to further improve perform...

In this article, an open slot split ring resonator (OSSRR) is introduced to realize a composite right/left handed (CRLH) transmission line structure in microstrip technology. The CRLH line is synthesized by etching OSSRR in the ground plane and interdigital capacitor in the microstrip line. Simulated and measured scattering parameter of the structure is presented. The dispersion characteristic ...

Four designs of substrate integrated waveguide (SIW) filter employing integrated broadside-coupled complementary split-ring resonators (BC-CSRR) are compared. By changing the orientation rings, four types of SIW unit cell are proposed and investigated and it is shown that, for one particular topology, two poles and two zeroes can be realised with a single unit cell. Bandpass filters based on th...

The design of filter antennas with reconfigurable band stops is proposed. They are meant for employment in ultrawideband cognitive radio (UWB-CR) systems, where unlicensed users communicate using adaptive pulses that have nulls in the bands used by licensed users. Neural networks or circuits implementing the Parks-McClellan algorithm can generate such pulses. With filter antennas, reconfigurabl...