過去的研究發現，高頻地波雷達頻譜射頻干擾以及背景雜訊會覆蓋目標物訊號，針對此問題，先前的文獻中已發展出一系列的雜訊濾除技術。本研究以此為基礎，發展目標物訊號提升技術，並針對桃園海岸架設的雙態雷達(Bistatic Radar)系統，進行海洋回波頻譜的模擬與驗證。 在訊號提升方面，本研究基於調頻截斷連續波(Frequency Modulated Interrupted Continuous Wave， FMICW)理論，推導目標物回波距離與截斷函數的關係。模擬分析發現，同一目標物的回波會在頻譜距離軸上重複出現，其相位與強度受Sinc函數影響。將模擬結果與彭佳嶼和東莒島陣列式岸基測波儀2020~2023年的實際資料驗證後，本研究引入同相積分(Coherent Integration)方式以提升目標物訊雜比(Signal-to-Noise Ratio， SNR)，結果顯示近距離目標物訊雜比可提升10至15 dB，遠距離可提升2至8 dB，最佳積分次數為30至40次。面對高功率背景雜訊，最佳積分次數為20至30次，將同相積分結合頻率域自適應雜波抑制演算法(Frequency domain Adaptive Clutter Suppression， FACS)，能更有效抑制雜訊並提升頻譜品質。 在海洋回波模擬方面，本研究運用Pierson-Moskowitz模型與動差法(Method of Moments)模擬一階與二階海洋回波頻譜，並基於雙態雷達理論建立不同來向角的頻譜模擬方法。將桃園觀音站雷達實際觀測資料進行波束成形來向角分析比對後，一階波特徵與模擬結果吻合，驗證了此模擬方式的可行性。;Previous studies have shown that radio frequency interference (RFI) and background noise in high-frequency surface wave radar (HFSWR) spectra can obscure target signals. To address this issue， a series of noise suppression techniques have been developed in the literature. Building upon these studies， this research develops a target signal enhancement technique and conducts simulations and validations of ocean echo spectra using a bistatic radar system deployed along the Taoyuan coast. For signal enhancement， this study derives the relationship between target echo range and the truncation function based on Frequency-Modulated Interrupted Continuous Wave (FMICW) theory. Simulation results indicate that echoes from the same target repeatedly appear along the spectral range axis， with their phase and intensity influenced by the Sinc function. After validating the simulation results with real observational data collected from the Pengjia Islet and Dongju Island coastal wave radar arrays between 2020 and 2023， coherent integration was introduced to improve the signal-to-noise ratio (SNR) of target signals. The results show that the SNR of short-range targets can be improved by 10–15 dB， while long-range targets achieve improvements of 2–8 dB， with the optimal number of integrations ranging from 30 to 40. Under high-power background noise conditions， combining coherent integration with the FACS algorithm can more effectively suppress noise and enhance spectral quality. For ocean echo simulations， this study employs the Pierson–Moskowitz model and the method of moments to simulate first-order and second-order ocean echo spectra. Furthermore， based on bistatic radar theory， a spectral simulation method for different incident angles is established. By comparing the beamforming direction-of-arrival analysis results from actual radar observations at the Guanyin Station in Taoyuan， the characteristics of the first-order waves are found to be consistent with the simulation results， thereby validating the feasibility of the proposed simulation approach.
