An Active Stabilization Technique Of A Homodyne Interferometer Based On PTDC For High Frequency Hydrophone Calibration

摘要

Under plane wave conditions, the ultrasonic pressure could be derived by the detected displacement with a stabilized homodyne interferometer, and then compare with the voltage output of the hydrophone, it could calibrate the hydrophone. Generally, what is noteworthy is that the disfigurement of the homodyne interferometer easily influenced by the low frequency noise in environment such as acoustic noise and water surface agitation. As a result, signal faded. Based on direct current phase tracking, an active stabilization technique was devised to maintain the quadrature working point for the interferometer. While the interferometer stabilization was maintained, most of environmental noises could be effectively compensated, and the ultrasonic signal fading problem could be figured out. An active stabilization technique of a homodyne type Michelson interferometer for calibrating the high frequency hydrophone is described in this article.