We propose to apply the surface acoustic wave (SAW) temperature sensor in the temperature control system of library and archive.When the temperature of library and archive changes

the output frequency of the SAW temperature sensor is linear with the temperature

thus the temperature can be measured.We also present the trace weighted function of the input transducer

and the influence of transducer electrode-numbers on the SAW power as two key problems of the SAW temperature sensor.The solutions to these problems are achieved in this study.The wavelet function is used as the trace weighted function of the input transducer

so that the sidelobes for the frequency characteristic curve of the SAW temperature sensor are suppressed.The more the transducer electrode number are

the weaker the bulk acoustic wave (BAW) is (i.e.

the more the transducer electrode-numbers are

the stronger the SAW is).As long as transducer electrode numbers are more than 40

the excited bulk acoustic wave (BAW) can be ignored

but the excited SAW is very strong.The design

fabrication and experiment for the SAW temperature sensor have been studied in detail.