## 4 Conclusions  
Due to the unique characteristics of high sea states on global shipping routes and issues such as defocusing in the high-resolution SAR imaging of moving targets, monitoring based solely on ship targets themselves is susceptible to interference, making it difficult to detect and identify ship targets. Ship wakes, as a special and relatively stable image phenomenon caused by ship motion, also contain valuable information such as the speed and direction of ship movement, thus serving as a powerful complement to ship target  
Figure 6: Comparison of detection performance in Radon transform domain. \begin{table}
\begin{tabular}{c c c c c} \hline \hline  & & **Angle Peak** & **Intensity of** & **Improvement** \\  & & **Point (\({}^{\circ}\))** & **Peak Point (dB)** & **(dB)** \\ \hline \multirow{3}{*}{Left wake} & Original image & 85 & 71.83 & / \\  & Filtered image & 85 & 71.62 & \(-\)0.21 \\ \cline{1-1}  & Enhanced image & 85 & 74.45 & 2.62 \\ \cline{1-1}  & Original image & 91 & 71.98 & / \\ \cline{1-1}  & Filtered image & 91 & 71.91 & \(-\)0.07 \\ \cline{1-1}  & Enhanced image & 91 & 74.68 & 2.70 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Performance evaluation results of wake enhancement. monitoring. The existing technical methods mainly focus on enhancing the image domain. This study aims to investigate the wake enhancement method during the imaging process of high-resolution spaceborne SAR, as the synthetic aperture time is relatively long, and there are significant differences between the echo signals of the wake itself and the sea surface background. To address the challenges posed by the dynamic nature of ship wakes and sea surface textures under complex sea conditions, we propose a ship wake enhancement method based on azimuth overlap sub-aperture amplitude image sequences using high-resolution spaceborne SAR. By performing histogram normalization and multi-sub-aperture image fusion enhancement processing to the OSMI data, the visualization and histogram distribution of real wake images are verified to enhance the clarity of wake images. Evaluation methods based on image quality and wake detection performance are investigated, and experiments conducted with AS01 SAR data demonstrate the accuracy and reliability of the proposed wake enhancement method. The subsequent application of various wake detection algorithms on the basis of the enhancement in this study will help improve the accuracy of spaceborne SAR wake detection and provide more significant support for typical situational applications, such as ship heading and speed estimation. This study is applicable for target monitoring in complex sea conditions. By integrating the scattering characteristics of ships themselves, it further improves the application of ocean surveillance systems in marine safety, fishery protection, and even, military anti-submarine operations. Currently, this achievement has been deployed in the \"Sea-Sight\" ocean situation analysis system and has been well-applied. Further research on wake enhancement in complex sea conditions using high-resolution spaceborne SAR requires investigating the coherence of wake characteristics at the mechanism level, optimizing sub-aperture imaging compensation parameters for wakes, and further improving peak intensity in the transform domain to enhance wake detection capabilities and motion parameter retrieval accuracy in practical applications. Conceptualization, X.X. ; methodology, L.Y. and P.W. ; validation, L.Y. and Y.L. ; data curation, Y.L. ; writing--original draft preparation, L.Y. ; writing--review and editing, Y.L. ; visualization, L.Y. and X.X. ; supervision, X.X. All authors have read and agreed to the published version of the manuscript. This research received no external funding. Not applicable. The original contributions presented in this study are included in the article. Further inquiries can be directed to the corresponding author.