Abstract:
In order to study the wireless detection technology of strain sensor. A microstrip antenna wireless strain sensor based on radio frequency identification (RFID) was proposed by using ultra high frequency RFID system through electromagnetic wave interaction. The microstrip antenna sensor, as a tag antenna, received the RFID signal, which activated the chip in RFID tag. The background noise can be eliminated by the signal modulation technology. Then, the effective signal returned to the antenna, and the deviation of the resonant frequency informed the reader of realizing the wireless passive strain detection. Two kinds of RFID microstrip antenna sensor, inserted-feeding type and edge-feeding type were designed. The operating gain, return loss and electric field strength were simulated and optimized by HFSS (high frequency structure simulator). Through the analysis of solid mechanics coupled with electromagnetics by COMSOL, the principle that the deviation of the resonant frequency was proportionally to the strain in these two types of sensors. The simulation results are consistent with the theoretical values, which can meet the requirements for structural strain measurement, and lay a theoretical foundation for experimental research.