Abstract: Sound source localization based on Time Delay Estimation（TDE） is one of the core of the algorithm in hearing aids. However, the estimation accuracy is often affected by the sampling rate and noise, which leads to the inaccuracy of location. In order to solve the problem, in this paper, combined with Fine Interpolation of Correlation Peak method（FICP）, an improved generalized cross correlation algorithm based on second correlation is proposed. In the proposed method, second correlation is adopted to reduce the interference of noise, FICP is used to improve the resolution of correlation function. The simulation results show that under both low SNR and high SNR environments, the proposed method can improve the performance of time delay estimation significantly.

Key words: time delay estimation, generalized cross correlation, second correlation, fine interpolation of correlation peak

摘要： 基于时延估计（TDE）的声源定位算法是数字助听器中的核心算法之一，其估计精度会受到噪声和采样频率等因素的影响，导致了定位的不准确性。针对这一问题，结合相关峰精确插值算法（FICP），提出了一种基于二次相关改进的广义互相关时延估计算法。该算法通过二次相关，有效地降低噪声的干扰，再利用FICP，提高相关函数的分辨率。仿真实验表明，无论在低信噪比，还是在高信噪比环境下，改进算法的时延估计性能都有了明显改善。

关键词: 时延估计, 广义互相关, 二次相关, 相关峰精确插值