Design of a RFID sensor for quality detection of fresh milk
A flexible RFID sensor tag based on capacitive sensor impedance analysis and RFID power and data trans⁃mission is proposed to address the need for convenient measurement of fresh dairy quality.The front-end interdigitated capacitive sensor is designed and optimized to sense changes in dairy quality through impedance analysis.The antenna parameters are optimized with simulation studies to improve the efficiency of wireless power supply,and the near-field communication data exchange format is used to normalize the data for wireless transmission and display.The anti-inter⁃ference capability of the sensor has been improved by studying the role of sensor front-end and high-frequency antenna coil shielding and optimizing them.Determination of dairy deterioration time nodes using pH as a reference value.The proposed method has been experimentally verified,and the results show that the sensor tag can work stably within the dis⁃tance of 1.5 cm,the maximum relative error of measurement is 3.28%.It can be concluded that the result of freshness judgement can effectively reflect the actual deterioration of dairy products.
RFID sensordairy quality testingimpedance measurementinterdigitated capacitornon-contact measure⁃ments