Surface acoustic wave propagation state measuring apparatus, surface acoustic wave propagation state measuring method, environmental change measuring device, environmental change measuring method, and multiple circumferential surface acoustic wave device

摘要

PROBLEM TO BE SOLVED: To highly precisely calculate a frequency variation in a multicirculation surface acoustic wave element.;SOLUTION: A frequency variation calculating device 20 includes a storage part 23 for storing preliminarily a data of a reference signal including a reference intensity and a reference phase of a surface acoustic wave in a resonance condition, and a reference frequency for exciting the surface acoustic wave, a resonance regulation part 24 for regulating a carrier frequency of a high-frequency burst signal to be brought into a resonance frequency, a waveform regulation part 25 for regulating the carrier frequency of the high-frequency burst signal to make a difference between a detected phase of a phase of a detection signal and the reference phase constant, and a calculation part 26 for calculating a difference between the carrier frequency regulated by the waveform regulation part 25 and the reference frequency, when the phase difference between the both gets constant.;COPYRIGHT: (C)2007,JPO&INPIT