US Patent 10140482 RFID scheme in harsh environments

A method for using an RFID tag to retain information of an environment, such as high temperature, that is beyond the operable limits of the RFID tag. The method generally comprises providing an RFID tag that has nonvolatile RFID memory that can communicate with an RFID interrogator system. Exposing the RFID tag to a first environment (such as a high temperature) that renders the RFID tag inoperable. Collecting a first sensor value of the first environment and storing the first sensor value in nonvolatile memory accessible by the RFID interrogation system. Later, exposing the RFID tag and the sensor to a second environment that renders the RFID tag operable (such as room temperature). Wirelessly transmitting the first sensor value to the RFID tag via the RFID interrogator system while the first sensor is in the second environment, and storing the first sensor value in the nonvolatile RFID memory while the RFID tag is in the second environment.