New SAW sensor-device with identification capability

SAW temperature sensors were simulated, designed and investigated. The new sensor generation is able to follow a request with a signal identifying the sensor and containing a change due to the physical value to be measured. The sensors do not require any separate energy source and can be used over a long period of time without maintenance. A remote measurement system will control the passive sensors, register the sensor answer and calculate the measured value. The sensors were designed to work at a frequency of 433.92 MHz. Several experiments have been done with temperature sensors, fabricated on LiNbO₃. The attenuation of the signals were obtained in dependence of the distance between the sensors and the control unit using request signals with a small power of 1 mW and less. The sensor and system design will be discussed in comparison to the results of the measurements