In order to solve the problem that traditional piezoelectric sensors (PZT) cannot be implanted into the material to monitor the internal sound field transmission of the material, an unbalanced Michelson interferometer is used to build an acoustic signal based on a phase shift fiber Bragg grating (PSFBG) Monitoring system, carried out acoustic signal transmission detection experiment, compared the signal characteristics of PSFBG and PZT two sensors; and studied the sensitivity and temperature stability of PSFBG signal. The results show that the sensitivity of PSFBG is higher than that of the commercial R15a acoustic emission PZT sensor, and the volume is much smaller than that of PZT. It can be applied to the detection of sound field transmission inside the material; it can work stably under a wide temperature threshold (- 20°C ~80°C) environment, with amplitude variation not more than 5%; The self-built PSFBG demodulation system is used to measure the acoustic signal in real time.
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