遙感探測不與觀測目標物直接接觸，是藉由拍攝影像或接收回波之方式隔空探知目標物性質的技術。由於觀測儀器無須直接放置於海上進行觀測，可避免儀器遭受到海洋環境外力之影響以及破壞，於惡劣海況時更突顯出其價值，為從事海洋科學研究的重要方法之一。
　　遙測所得資料為觀測區域之影像，需要利用適當之影像處理方法分析被觀測目標物之特性。本文選用具有分析非定常訊號的小波轉換理論分析遙測波場影像，小波轉換之基本原理與傳統之影像處理方法-傅立葉轉換類似，但小波轉換分析方法可同時表現出被分析影像中空間域與波數域(空間頻率域)的資訊，且在分析波場影像時會隨著被分析訊號之波長(空間頻率)特性調整其分析的範圍。為將小波轉換理論應用於波場影像分析，本文推導出小波參數與波浪參數之間的關係，以及小波轉換中調變視窗之大小與波場影像間之關係。經由本文方法對多種數值模擬均勻以及非均勻波場分析驗證後，除了證實本文分析方法正確無誤外，亦得知二維小波轉換能完整描述空間中不同區域之波譜特性，於分析非均勻性波場以及點波源波場時，更能突顯出本法之優越性。
　　本文並進一步對二維小波轉換於實務應用時，小波轉換中一些參數對分析結果所產生之影響作一探討。本文利用小波轉換分析影像中不同區域之影像譜，結果顯示於分析極近岸波場影像或影像邊緣區域時，波場影像之分析位置與影像邊界或影像中陸地邊界之距離以對應於主成份波1.08倍波長以上為佳。此外，本文以數值模擬之點波源波場探討波形震盪個數對空間域以及波數域解析力造成之影響。分析結果得知，應用二維Morlet小波母函數分析遙測影像時，波形震盪個數取在5~10之間較為適當。

　　Remote sensing instrumentations signal electric-magnetic waves and detect their reflections to obtain the characteristics of objects. There is no requirement of physical contacts between the probes and the objects. This feature contributes to the cost control and enhancing the capability of wave monitoring since the direct impacts from the relevant environmental loads to the instrumentations can be avoided.
　　Reflections of electric-magnetic signals are represented as grey-scale images, in which information of waves can be extracted. Due to the topography effects, however, the wave images are often pronouns high non-homogeneity. To retrieve the wave characteristics from those wave field images, Wavelet Transform Analysis is adopted in present study to establish the 2-D Wavelet Transform directional wave-number spectrum estimation method. Unlike traditional Fourier Transform Method, Wavelet Transform Analysis is capable of constructing the spatial and spectral structures from non-homogeneous images. Moreover, the optimal resolution of both the spatial and spectral domain could be yielded by adjusting the scale and sifting the location of mother wavelet function. The relationship between the Wavelet coefficients and wave spectral parameters as well as the size of modulated window and the wave image are derived accordingly afterward. From the numerical simulation tests, the validity and feasibility of proposed method are examined.
　　To justify the accuracy of this method, images of two central wave sources conditions and random wave fields are simulated and used as the inputs of propose method. From the results, it is suggested that the distance between the modulated window centers to the image border should not less than 1.08 times the peak frequency wave length. 　　　
Furthermore, the parameter n0 of the Morlet mother wavelet function should be selected in the range 5~10 to obtain optimal resolution in both spatial and spectral domain.

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