Multipath Environment, The Sound Source Is Measured To The Technology

To find the direction of an acoustic source in multi-path environment,the relative delay between two received signals for the direct sound must be determined. The generalized cross-correlation (GCC) is the most commonly used method for time delay estimation (TDE).In this technique,the delay estimated is obtained as the time-lag that maximizes the cross-correlation between filtered versions of the received signals. This problem will be difficult if room acoustic reverberation is exist. The GCC methods can give good results when the multi-path is not very high,but when the multi-path becomes important the GCC methods will fail.The multi-path is surely exist in practice. The adaptive eigenvalue depositon algorithm (AEDA) is an effective method. In this method,we must normalize the multi-path impulse response every step. Because of this disadvantage,we propose an NLMS-based cross-relation method. In different room reverberation,we compare the NLMS-based cross-relation method with GCC,corss-correlation methods.The results show that the proposed method performs well.The results estimated wih NLMS-based cross-relation method will be not unique if the two received signals are correlated. In this paper, we explain these problems in detail and give some solutions . The simulation shows that the correct rate of the estimated results after decorrelation is higher than the correct rate before decorrelation.