Abstract: The accurate delay of digital signal is widely used in the domain of signal processing，it is more important that the implementation of real data series in project.From the view of none distortion linear system，the paper presents a new method which based on linear shift invariable system implements the accurate time delay，meanwhile its performance analyses and the issues in project application are given.Based on the relationship between signal’s time domain and its the authors presents the implementation of linear phase weighting method in frequency domain.In the end，the paper carried out the comparison of performance from the time delay error，the system frequency response and whole average error which the paper introduced.The experiment result indicates that these methods have the property of high precision in time delay and convenience to implement.

Key words: none distortion linear system, accurate time delay, fractional time delay filter, linear phase weighting

摘要： 数字信号的精确时延在信号处理领域有着广泛的应用，特别是实序列时延的实现，在工程实践中有着重要的意义。提出了基于线性移不变系统实现精确延时的方法并进行了性能分析，并指出了工程设计要点；根据信号的时延与其频谱的对应关系，给出了基于线性相位加权的频域实现方法。通过时延误差、系统的频率响应和引入总体平均误差参数对不同方法的性能进行了比较。实验结果表明，这两类方法具有延时精度高，实现方便等优点。

关键词: 无失真传输系统, 精确时延, 分数时延滤波器, 线性加权