Out-of-Sight Salt-Water Concentration Sensing Using Chipless-RFID for Pipeline Coating Integrity
In this paper, out of sight microwave concentration sensing is presented to detect salty water ingress in pipeline coatings. Unlike conventional sensors that monitor pipeline corrosion, chipless radio frequency identification (RFID) sensors take a predictive approach by monitoring the environmental conditions at the pipe surface. The proposed sensor is composed of a spiral ring resonator, two tag antennas, and two reader antennas. The integrated system is built on a flexible substrate and is conformally wrapped around the pipe. A two-port measurement is performed at the transceiver and the resonant frequency of the sensor is wirelessly monitored. It is shown that the microwave sensor has potential for monitoring salt water ingress in pipeline coatings.