标准时频变换的潮汐预测初探

Primary study of tidal level prediction using normal time-frequency transform

针对传统潮汐调和分析中计算复杂和观测数据需求较长的问题,该文提出基于标准时频变换理论的潮汐预测方法。潮汐中的调和成分在其标准时频谱中可以自动显示,并且运用无为方法可以将其直接提取而无须逆变换。在不参考潮汐表的情况下,该文处理了半年的观测数据,提取了主要的调和分潮来进行重构和预测。结果表明,无为方法在潮汐的短期预测中有着较高精度和较小计算量。多次运用无为方法提取,在一定程度上可以抑制多分量信号在时频变换谱中的边缘效应,并得到有利于预测的即时调和信息。

To solve the problem of conventional tide analysis which always need a long period data and large calculation to make sure a good result,this contribution proposed a new method which is based on normal time-frequency transform（NTFT）to tide prediction.The harmonic components of tide signal not only can be appeared in its normal time-frequency spectrum but also can be extracted by＂Inaction method＂without an inverse transform.Apply NTFT to half year tide observation,we extracted main tide constituents which can be used in reconstruction and prediction.In addition,tide table have not been used in this study.Results demonstrate the capacity of＂inaction method＂in short-term tidal level forecasts.Apply this method repeatedly,edge effect can be attenuated and current instantaneous harmonic information can be obtained,which may lead to a good prediction.