資料浮標觀測波浪具有不受水深限制的特點，是波浪現場觀測最主要也是最常用的方式。資料浮標量測波面水體的垂直加速度變化、經傅立葉運算及函數轉換後可得到水位譜。其中，由加速度譜轉換為水位譜時受低頻雜訊干擾，常使波譜形狀產生嚴重扭曲，對於此一干擾，本文基於正規化波譜形狀具有相似性之特性，建立一濾除雜訊能量之方法。本文在觀測樁旁佈放資料浮標，同時進行波浪量測，用觀測樁上超音波水位計測得之水位譜建立波譜低頻頻率與能量之公式，將之應用於資料浮標，去除低頻處之雜訊。此法有效消除了現行資料浮標無法完全濾除低頻雜訊的缺點，經數據比對證實，本文提出之濾除雜訊方法大幅提升浮標波浪量測之準確度。

Data buoy is the most frequent applied alternatives on the measurement of oceanographical data.The displacement spectra can be obtained by analyzing the observed heave of the buoy hull. The low frequency noise contaminant, which can be magnified due to the linear conversion from the acceleration spectrum to the displacement spectrum, is the major cause of the inaccuracy. To reduce the error, a correction method to eliminate low-frequency noise is developed based on the previous spectrum’s shape theory. The low-frequency noise correction method based on the relation of low-frequency and energy, estimate the noise well and improve the accuracy of buoy measurements.

1. 俞聿修(1992) “隨機波浪及其工程運用”，大連理工大學出版社。
2. 郭一羽(2001)，”海岸工程學”，文山書局。
3. 陳嘉元、黃明志、徐仕昇、連永順(1996)，”Butterworth 低通濾波器在降低資料浮標低頻雜訊之應用”，海洋工程研討會論文集。
4. 黃明志(1998)，”浮標測波低頻雜訊修正函數決定方法”，海洋工程研討會論文集。
5. 鄧中柱(1994) “作業化資料浮標之評介”，海象預報與分析研討會論文集。
6. 黃煌輝、江文山、廖顯仁(2003)，”雲林海域之穩定風浪頻譜”，海洋工程研討會論文集。
7. 簡仲璟、郭一羽 (1994) 「近岸波浪頻譜形狀之研究」，第十六屆海洋工程研會論文集，第A193-A210頁。
8. 邱銘達,(2001)，“資料浮標量測波高波向準確度提升研究”，國立成功大學碩士論文。
9. Earle, M. D. and K. A. Bush (1982) “Strapped-down accelerometer effects on NDBO wave measurements”, Proc. IEEE Conference of Oceans’82, pp. 838-843. Washington, D.C., U.S.A.
10. Earle, M. D. and K. E. Steele, and Y.H.L. Hsu (1984) “Wave spectral corrections for measurements with hull-fixed accelerometers”, Proc. IEEE Conference of Oceans’82, pp. 838-843. Washington, D.C., U.S.A.
11. Kenneth E. Steele. Joseph Chi-Kin Lau, and Yuan-Huang L. Hsu (1985) “Theory and application of calibration techniques for an NDBC directional wave measurements buoy”, IEEE journal of oceanic engineering. Vol. OE-10, NO. 4, October 1985.
12. Lang(1987), Norman “The empirical determination of a noise function for NDBC buoys with strapped-down accelerometers”, Proc. IEEE Conference of Oceans’87, pp. 225-228. Halifax, NS Canada.
13. Longuet-Higgins, M.S., Cartwright, D.E. & Smith, N.D(1963) “Observations of the directional spectrum of sea wave using the motions of a floating buoy”, Proc. Conf. Ocean Wave Spectra, Prentice-Hall Inc., pp.11~132,1963