High precision signal processing algorithm to evaluate the SAW properties as a function of temperature

In order to measure the temperature using Surface Acoustic Wave (SAW) devices, it is important to characterize the substrate material over a desired temperature range, which strongly depends on the accuracy of the analysis algorithm used. This paper presents a special signal processing algorithm, which accurately evaluates the desired SAW properties as functions of temperature. The analysis algorithm is performed in two steps. In the first step, the algorithm determines the center frequency of the delay lines and obtains the delay time difference by cross correlating the signals out of the short and long delay lines. The extracted parameters are then used in a second analysis step to calculate the acoustic properties of the SAW material as a function of temperature. To validate this algorithm, its accuracy is studied.