Acoustic Detection And Bit Accurate Delay Estimation And Post-processing Technology

The intelligent mine will be the most important weapon to attack armed helicopters in the future war and passive acoustic detection is the key technology. This paper details TDE (time-delay estimation) and post-processing.At first, this paper introduces the theory of passive acoustic localization, the factors of affecting the localization accuracy and the methods to improve the localization accuracy briefly. Based on this, it analyzes the necessity of post-processing from the impact of environment and the character of signal respectively in detail.Then, this paper presents a fast time-delay estimation algorithm FICP (Fine Interpolation of Correlation Peak) . This algorithm can effectively reduce the impact of signal non-stationary and improve the accuracy of TDE (time-delay estimation) without increasing calculating complexity. What's more, it can reduce the interference caused by wide band noise.At last, an adaptive two-stage structure for post-processing by using kalman filter is presented. Based on this structure, this paper creates some models for the whole localization system and selects more suitable values for some key parameters. Result by experiment proves that this post-processing method can improve the localization accuracy further.