一种无线电话音信号时差估计方法

无线电话音信号的时差估计一直是个难题,其主要原因有话音信号带宽较窄且非平稳、在时域上具有非连续性及无线电信道（特别是短波信道）衰落的非一致性。针对上述特点,提出了使用短时处理技术来估计两路信号互相关谱的线性相位的无线电话音信号时差估计方案。新方案融合了话音激活检测技术和短时分段处理技术,并使用加权最小二乘相位拟合方法来求解时差。对比实验表明新方案的时差估计效果显著优于经典的广义互相关算法。

A time delay estimation method for radio speech signals

Time delay estimation(TDE) for radio speech signals has long been a difficult problem mainly due to the following reasons. First,the bandwidth of speech signal is very narrow. Second,speech signal is non-stationary and is not continuous in time. Third,the attenuation functions of different radio channels are not concordant,especially for shortwave channels. According to above features,this paper proposes a new TDE scheme for radio speech signals. The new scheme incorporates the voice activity detection and short time analysis techniques in estimating the cross-correlation(CC)spectra,and employs a weighted least square method to solve the time delay based on the phase of the estimated CC spectra.Comparative experiments show the new scheme is superror to classical generalized cross-correlation method.