臺灣東北海域反算底質音響參數分析研究

Geo-acoustic Parameters Estimation by Spectrum Ratio Method Offshore Northeastern Taiwan

蔡明格(Ming-Ker Tsai)

指導教授 ： 陳琪芳

國立臺灣大學/工學院/工程科學及海洋工程學研究所/碩士(2011年)

https://doi.org/10.6342/NTU.2011.10304

摘要

臺灣東北海域水深較東部海域淺‭, ‬聲波受底質影響較大，因此在臺灣東北海域做聲學研究時，底質聲學參數(含聲速、密度、衰減係數及以上參數隨底層厚度的變化)就變的格外重要。蒐集底質資料主要有兩種方式，其一為岩心採樣方式，獲取底質聲學參數作業困難且僅有點的資料，其二為反算，本研究擬用底層聲納系統資料以頻譜比對法反算的方式來得到底質之聲學參數資料，以提供本海洋聲學整合計劃之研究。雖先前國內有先行分析過海研一號BATHY-2000資料，但其聲訊資料經過平方處理無相位資料無法處理。本文中將對於海研二號98年度底拖式聲納SB-512i之資料進行分析，並以頻譜比對法所發展出反算連續變頻聲納聲波衰減為基礎，建立對台灣東北海域所蒐集連續變頻聲納資料作大面積之計算聲波在沉積物中之衰減係數之方法，並與Hamilton 之回歸分析去作比對以得到相關底質聲學參數之地音模型(含聲速、密度、衰減係數及以上參數隨底層厚度的變化等)，提供水下聲學之研究。

關鍵字

頻譜比對法 ； 底質音響參數

並列摘要

In The continental shelf regions offshore northeastern Taiwan, underwater sound propagation is influenced by the sediment enormously, so doing the acoustic studies in this regions, sediment acoustic parameters (including velocity, density, attenuation coefficient versus depth) becomes particularly important. Sediment data is collected mainly in two ways, one is to obtain core samples, however it’s difficult and limited by the number of site-sample. The second way is the geo-acoustic inversion, which used data of chirp sonar system to inverse the geo-acoustic parameter by the spectrum ratio method. The purpose of this research is to establish the geo-acoustic parameter in large area database of the northeast of Taiwan and to improve the accuracy of simulation in underwater acoustic propegation.

並列關鍵字

Spectrum Ratio ； geo-acoustic parameter

參考文獻

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