本文利用中壢特高頻雷達在觀測大氣訊號時，常有雜訊污染訊號，使訊號無法有效利用。在本研究中，主要針對飛機及降雨對雷達訊號的干擾來進行濾波，而使用的方法為新技術希爾伯-黃轉換（Hilbert-Huang Transform，HHT），在濾除飛機訊號時，也藉助基波轉換（Wavelet Transform，WT）在數學上的貢獻，與HHT相輔相成，有效率的進行濾波，最後而發展了一套「自動化濾波」。而濾波結果彼此比較都卜勒速度、頻寬、頻譜等，判斷是否正確，最後再看看其結果是否在雷達訊號裡接近大氣的波動，使其有效再利用與分析。 When we use Chung Li VHF radar to observe atmospheric signal, there are some noise make the signal feckless. In this study, we use wavelet transform and a new method called Hilbert-Huang Transform to filter the plane and precipitation signal, that is, the noise. By this way, we create a process called "auto-filtering process" to filter the noise from normal atmospheric signal. We used the observed data to calculate the echo power, the Doppler frequency shift, spectral width and signal-to-noise ratio by the moment method. After comparing these outcomes with normal atmospheric signal, we can determine if the method is useable.
