An encoded reconfigurable RFID strain sensor and its information fusion method

Abstract

Chip-based radio frequency identification (RFID) sensor systems have been investigated for structural health monitoring (SHM) applications. However, there are disadvantages to using chips in sensor tags in terms of price, robustness and detecting power. In this paper, we propose a reconfigurable RFID-based chipless tag sensor for strain detection, which detects structural strain by observing the offset of the resonant frequency of the antenna and incorporates an encoding unit for tag identification. To realize the reconfigurability of the antenna, a PIN diode is added to control the antenna, and the frequency reconfigurability of the antenna is realized by controlling the turn on/off of the PIN diodes. The Kalman filter algorithm is used to realize the information fusion of multiple sensors to improve the sensor detection accuracy, and the background noise data enhancement is used to expand the original data samples to fuse the information of the three sensors' data. The relative inaccuracy is roughly 33.5% less after fusion compared to the measurement alone. The antenna was fabricated by an etching process and measured using VNA to verify the accuracy of the antenna simulation results.

A Novel 4-Bit U-Shaped Chipless Flexible Substrate RFID Sensor Sensing Characterization Study

“…Depending on the processing type of the flexible sensor, some printed flexible chipless RFID strain sensors prepared by inkjet printing [15][16] and direct stamping [17] methods have been reported in the literature. According to the type of base material, flexible strain sensors are further divided into polymer compounds [18], nanomaterials [19], composite materials [20][21], conductive fabrics [24], etc. Among them, the cost of conductive fabric materials is lower, but its rough surface and cross structure lead to lower resistivity and greater antenna gain loss.…”

“…In the reconfigurable research of RFID, it can be divided into mode reconfiguration [23] and frequency reconfiguration [24]. Frequency reconfiguration has attracted more attention because it is simple and easy to measure.…”