一种改进的分数时延估计方法及应用
Improved Fractional Time Delay Estimation Method and Its Application

传统的分数时延估计算法对环境噪声和混响噪声比较敏感，在复杂的实际环境中，算法性能会严重下降。为进一步提高时延估计算法性能，提出一种基于广义互相关（Generalized cross correlation,GCC)改进算法的广义互相关 最大似然相位补偿（ GCC Maximum likelihood phase compensation,GCC MLP)分数延时估计算法。该算法改进了GCC频域加权函数，并将线性相位补偿应用于频域互相关谱，获得连续的分数时延估计值，进一步提高了分数时延估计的精确性。仿真结果表明，GCC MLP相位补偿分数时延估计算法增强了对环境噪声和混响噪声的鲁棒性，减小了时延估计误差，算法性能优于曲线拟合、Sinc插值等传统分数时延估计算法。
Traditional fractional time delay estimation (TDE) algorithm is se nsitive to ambient noise and reverberation noise, and the algorithm performance is severely degraded in the complex environment. To improve the accuracy of time delay estimation, a GCC maximum likelihood phase compensation (GCC MLP) phase compensation fract ional time delay estimation approach is proposed based on generalized cross correlation(GCC). The frequency domain weighting function is also improved for GCC algorithm. At the same time, linear phase compensation is applied to the cross correlation spectrum in frequency domain and a continuous time delay estimator is obtained. Simulation comparition between the proposed algorithm and the other fractional TDE algorithms demonstrates that the proposed algorithm outperforms the curve fitting algorithm and the sinc interpolation algorithm. Meanwhile the robustness to the noisy and the reverberant conditions is reinforced, the time delay estimation error also decreases. Therefore, GCC-MLP phase compensation fractional time delay estimation algorithm can be widely used in sound source direction of arrival estimation and sound source localization.