Detection of Defects in Non-Metallic Composite Material Based on Electronically Controlled Spoof Surface Plasmon Polaritons

A novel sensor based on electronically controlled spoof surface plasmon polaritons (SSPPs) is proposed to detect internal defects in non-metallic composites. The designed sensor is flexible and can be wrapped around the materials under test (MUT), therefore, compared with non-flexible sensors, it has a great advantage in detecting curved MUT. Moreover, traditional microwave sensors have to scan the MUT by the way of mechanical moving which consumes much time. For improving the detection speed, the electronic control scheme is adopted to control the sensing area of designed sensor, so as to replace mechanical moving. The detection is based on monitoring change in resonance frequency of the designed sensor which is caused by the defects. The sensor has the advantages of high sensitivity, fast detection speed and it is very convenient to detect curved MUT.