RFID Harmonics-Based Sub-Millimeter Vibration Sensing

In industrial monitoring, the accurate detection of subtle mechanical vibrations is essential for implementing effective preventive maintenance strategies and improving equipment longevity. However, current RFID-based sensing technologies are hindered by environmental noise and the inherent limitations of signal wavelengths. To address these issues, we introduce TagVibra, an innovative RFID-based system enhanced by the Differential Phase Amplification (DPA) algorithm. This algorithm harnesses the modulation characteristics of RFID technology along with the harmonic effects of RFID tags to markedly enhance vibration detection accuracy. TagVibra has been implemented on the USRP platform, and experimental results confirm its ability to detect minute vibrations down to 0.3 mm with an average frequency estimation error of less than 0.9 Hz. This breakthrough significantly advances the capabilities for early fault diagnosis in high-precision industrial settings.