Passive Chipless Wireless Sensor for Two-Dimensional Displacement Measurement

A novel passive chipless wireless sensor principle for a two-dimensional displacement measurement is presented. The working principle is based on detuning of a complementary split ring resonator by a controlled change of its coupling capacitance. The fully planar build-up and the opportunity of the utilization of ceramic substrates allow an application at very high temperatures. Besides high temperature, the sensor principle shows an inherent robustness against other disturbances in harsh environments, e.g. high electric or magnetic field strength. Additional identification capabilities allow to distinguish between different sensors. By the utilization of a polarization decoupling scheme, an improved separation between response signal of the sensor and various interferences is achieved. A prototype, measuring a two-dimensional displacement in the range of some millimeters, was built to approve the theoretical considerations.