数字预失真系统整数时延估计方法研究

Research on integer time delay estimation method of digital predistortion system

在数字预失真系统中,相关检测法是常用的时延估计算法。为了降低相关函数对噪声的敏感度,减少数字预失真系统时间延迟估计误差,将希尔伯特差值法和不同加权函数的广义相关时延估计算法相结合,并通过仿真比较,选取时延估计性能较好的基于CC(cross correlation)加权的广义相关希尔伯特差值算法用于数字预失真系统的整数时延估计。仿真结果表明:基于CC加权的广义相关希尔伯特差值算法用时较少,受噪声影响较小,时延估计性能较好,能有效降低时间延迟估计误差,提高系统性能,有利于实际应用。

In digital predistortion systems,correlation detection method is a commonly used time delay estimation algorithm.In order to reduce the sensitivity of the correlation function to noise and reduce the time delay estimation error of the digital predistortion system,this paper combines the Hilbert interpolation method with the generalized cross correlation time delay estimation algorithm with different weighting functions,and selects generalized correlation Hilbert difference algorithm based on CC weighting with better time delay estimation performance for integer time delay estimation of digital predistortion system through simulation comparison.The simulation results show that the generalized cross correlation Hilbert difference algorithm based on CC weighting takes less time,is less affected by noise,and has better time delay estimation performance,which can effectively reduce the time delay estimation error,improve system performance,and is good for practical applications.