基于小波变换的OTDR降噪算法研究

Research on OTDR denoise algorithm based on wavelet transform

传统的滤波方法在降低光时域反射仪(OTDR)曲线噪声的同时,会展宽其盲区,不利于OTDR性能指标的提升。研究了OTDR测试曲线的滤波降噪问题,使用基于小波变换的滤波算法对OTDR设备的测试曲线进行处理,可以显著提高信噪比。针对OTDR的特性,以及硬阈值和软阈值法的不足,引入特殊的阈值处理算法,可以更好地保持反射事件的边缘,对目前商用化OTDR产品性能的进一步提升具有重要意义。

While reducing the noise of optical time domain reflectometer(OTDR) curve, the traditional filtering method will widen its dead zone, and it threats the improvement of OTDR performance. This paper figures out the question of denoise for OTDR test curve by filtering. Processing the OTDR test curve using the filtering method based on wavelet transform, which can significantly improve the signal to noise ratio of the equipment. According to the characteristics of OTDR, and the weakness of hard threshold and soft threshold methods, the paper introduces a special threshold processing algorithm, which will maintain the edge of reflection events, and is of great significance to further improve the performance of commercial OTDR products.