从白光干涉的基本理论出发，分析了双折色散对偏振祸合测试的影响，提出了提高偏振祸合测试最大测量长度的频域分析的方案。在实验室已研制出的分布式偏振祸合测试仪的基础上，搭建了频域分析的系统，完成了LabVIEW软件系统的设计，进行了白光干涉光谱算法的研究。同时实验验证了有关频域理论的理论分析，计算出了被测保偏光纤祸合强度，延长了偏振祸合测试的距离。-White light interference from the basic theory, analysis of the dispersion on the two-fold test of the polarization coupling is proposed to improve the measurement of the polarization coupling length of the maximum test frequency domain analysis program. In the laboratory have developed a distributed polarization coupling on the basis of the test instrument, built the system frequency domain analysis, completed a LabVIEW software system design, the white light interference spectrum algorithm. At the same time experiments on the theoretical analysis of frequency domain theory to calculate the PMF of the measured coupling strength, extending the distance between the test polarization coupling.