中文摘要：

为了提高光纤中色散的测量精度和降低测量成本，提出了一套基于数字鉴相的色度色散的测量方案。采用低速率的模数转换器和全相位快速傅里叶变换的数字相位鉴别算法替代传统的模拟鉴相器件，利用粒子群优化算法对接收数据进行曲线拟合处理，实现了高精度的色散测量。数值分析了采样率、信噪比和快速傅里叶变换长度等因素对数字相位鉴别精度的影响，实验验证了测量系统的准确性。实验结果表明，对于不同长度的G.652 光纤，在波长1550 nm处，累积色散测量不确定度小于10 ps/nm，结果优于目前城域网环境下的商用色散测试仪的测量精度。

英文摘要：

In order to improve chromatic dispersion （CD） measurement accuracy and reduce cost, a chromatic dispersion measurement method based on digital phase detector is proposed. The traditional analog phase detector is replaced by an analog to digital converter with low sampling rate and a digital phase detecting algorithm based on all phase fast Fourier transform （FFT）, and a particle swarm optimization （PSO） algorithm is applied to the process of curve fitting. High accuracy chromatic dispersion measurement is achieved. The effects of sampling rate, signal noise ratio and FFT length on digital phase detection accuracy are also analyzed. Experiments on verifying the accuracy of the measurement system are carried out. Experiment results show that the accumulated chromatic dispersion uncertainty of G.652 fiber with different lengths at 1550 nm is less than 10 ps/nm, which is better than that of the commercial CD analyzer in metropolitan area network environment.