水声信号的光纤DSPI检测

Detecting hydrosonic signal using optical fiber DSPI

以光纤数字光斑模式干涉仪(DSPI)为基础,配以等离子耦合器阵列(PCD)和快速数字信号处理机(DSP)等设备,构成水声信号的检测系统.在水声压作用下,干涉仪的信号光和参考光产生相位差,形成干涉光的波纹地图,PCD阵列摄取该波纹图给DSP,处理机执行程序,由光强差之和算出相位差,从而测得水声信号压强.实验证明,光纤DSPI方法检测信号,可以简化电路、降低电子噪声,具有花费较低、相位分辨率高、结构灵活的特点.

A hydrosonic signal detecting system is introduced. It is based on Optical Fiber Digital Speckle Pattern Interferometer, and matched with PCD, DSP etc. Under hydrosonic pressure, a phase difference is produced between signal light and reference light in the interferometer, so a Moire map is formed. PCD device takes it and transmits it to DSP. A program was made in DSP to calculate the differences of the light intensities, add them up, get the phase difference. Then the hydrosonic pressure is acquired. Experimental results demonstrate that the method can concise circuit and decrease electronic noise.