結合適應性混合式最小均方值演算法在時間延遲估測之三元陣列目標估測

聲納系統是利用聲學訊號經由確定位置的水下目標物來傳播的水下技術系統; 可以分成;主動式和被動式聲納兩類。被動式聲納 (passive sonar)系統是由大尺度的水聽器 (Hydrophones) 所組成，利用從聲學感測器陣列接收到的雜訊訊號來估測目標的距離和角度。被動式聲納並不會主動發送聲波，因此不會使自身的位置曝露出來，適合應用於潛艇設備上。本論文旨在研究被動式聲納系統有關測定目標距離和方位等技術。傳統的感測器陣列排列方式是將三個感測器放置在一等間距的直線上，此方法稱為線性三元陣列測距。而在較新的文獻中，已將感測器陣列由等間距發展至不等間距，且更進一步推廣至非直線的排列方式，稱為非線性三元陣列測距。無論線性或是非線性的三元陣列測距技術，各個感測器間接收到的訊號彼此間之時間延遲 (time delay) 是我們在做對目標估測時非常重要的參數(訊息) 。它的估測確度將直接影響到目標估測結果的精確度，因此在三元陣列測距技術中，時間延遲估測技術的選擇也是相當重要的議題。本論文主要採用時間和轉換空間領域之混合式均方值適應性演算法來執行時間延遲估測，並將其結果套用至三元陣列測距技術上，以達到較佳的測距效果。最後以電腦模擬方式來證實我們所採用的方法確實優於其他傳統適應性算法。

關鍵字

時間延遲估測；三元陣列定位；混合式最小均方值演算法

並列摘要

Passive Sonar systems make use of the target noise received from the acoustic sensor array to determine the target distance and angular. In passive sonar system, we do not transmit sound wave; it equips with the submarine amount. Linear three-element array ranging technique has been one of the most popular approaches among the sensor array ranging systems; it arranges the three sensors of array on an equidistant line. Recently, to improve the flexibility of target ranging system, other approach has been considered, where the three sensors are not arranging on a line and distance between sensors is not equidistant. It is referred to as the non-linear three elements array ranging. To obtain more accurate localization for the Target sources, the techniques for time-delay estimation are vital for target ranging, for both of linear and non- linear three elements array ranging. It directly affects the result of localizing the target sources. In this thesis, we focus on the adaptive hybrid LMS (HLMS) filtering algorithm for extracting the information of time delay between related sensors and apply it for the Target sources ranging. To obtain the accurate delay estimation results, we adopt the hybrid LMS (HLMS) adaptation algorithm; it could achieve better performance regarding TDE and having faster convergence speed property. From simulation results, we verify the merits of the technique mentioned above compared with other conventional approaches for target sources ranging.

並列關鍵字

TDE ； Three-Elements Array Ranging ； HLMS

參考文獻

[1] G. C. Cater, “Coherence time delay estimation,” Proc. IEEE, vol. 75, no. 2, pp. 236-255, 1987.

[4] Y. T .Chan, J .M. Riley, and T.B. Plant, “A parameter estimation approach to time delay estimation and signal detection,” IEEE Trans. on Acoustics, Speech and Signal Processing, vol. ASSP-28, no. 1, pp. 8-16, 1980.

[5] S. J. Chern and S. N. Lin, “An adaptive time delay estimation with direct computation formula,” J. of Acoust. Soc. of Amer., vol. 96, no. 2, pp. 811-820, 1994.

[6] S. N. Lin and S. J. Chern, “A new adaptive constrained LMS time delay estimation algorithm,” Signal Processing, vol. 71, no. 1, pp. 29-44, 1998.

[7] S. J. Chern, J. C. Horng, and K. M. Wong, “The performance of hybrid LMS adaptive algorithm,” Signal Processing, vol. 44, pp. 67-88, 1995.

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結合適應性混合式最小均方值演算法在時間延遲估測之三元陣列目標估測

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