海面舰船广义雷达散射理论分析与高效建模技术研究

The modeling of Electromagnetic (EM) scattering from sea and ship is an important tool to obtain the radar echoes of ship. Generally, since the sea and ship involve an electrically extra-large scale scattering problem, how to effectively simulate it has always been one of difficulties in the areas of computational electromagnetics and radar engineering. Since the far-field condition of ship is not easily satisfied, its scattering characteristics in near-field zone are necessarily analyzed. This project is aiming to analyze the generalized radar scattering theories of the sea-ship target in both far-field and near-field zones and to develop the scattering simulation techniques, thus to the implementation of high-performance simulation and scattering characteristic analysis. Firstly, according to the EM scattering mechanisms in terms of different distances between radar and ship, the relevant scattering models are explored to improve the computation accuracy and flexibility of high-frequency methods in near-field scenarios. Secondly, the integrated simulation technique is investigated for the composite problem involving sea and ship, and the graphics processing unit (GPU) parallel computation is explored to develop a novel simulation platform combining the Optix ray tracing engine and high-frequency methods, thus to effectively accelerate scattering simulations and solve the computational capability limitation for the extra-large scale scattering problem. Finally, the near-field experiment is discussed in the outfield environment, and the accuracy and effectiveness of proposed methods will be demonstrated by the comparisons with full-wave numerical methods and with outfield experimental results.

海面舰船的电磁散射建模分析是获取舰船雷达散射特性一个重要技术手段。通常，海面舰船具有超电大尺寸规模，如何对其进行有效的电磁计算一直是电磁学和雷达工程中的难点。舰船的远场条件不易满足，海面舰船的近场电磁散射特性分析显得尤为必要。本项目拟开展包括近场、远场在内的海面舰船广义雷达散射理论和电磁建模技术研究，实现海面舰船的高效电磁散射计算和特性分析。首先，根据不同雷达近场条件下舰船电磁作用机理提出相应的电磁散射模型，提高近场散射中高频方法的计算精度和适用性。其次，研究包括海面与舰船在内的一体化建模技术和图形处理单元（GPU）并行计算技术，构建基于Optix射线追踪器与高频方法相结合的新型仿真平台，以此大幅度提高射线追踪过程的计算效率，解决超电大尺寸海面舰船的电磁散射计算能力问题。最后，开展模拟外场条件下的近场散射实验，通过数值方法对比和外场实验对比两种方案来验证所提理论和技术的正确性和适用性。

为了维护我国的海洋权益、巩固我国的国防安全，针对海面舰船电磁散射建模技术研究一直是热门话题，军事中常见的X波段下的舰船散射问题必然是近场问题，与传统的目标远场散射问题相比，海面舰船的电磁散射具有相对的特殊性。.本项目结合计算电磁学方法以及近场电磁散射理论，建立基于目标近场条件下的海面舰船近场电磁散射模型，以此提高近场散射中高频方法的计算精度和适用性。其次，研究了包括海面与舰船在内的一体化建模技术和图形处理单元（GPU）并行计算技术，构建基于Optix射线追踪器与高频方法相结合的新型仿真平台，以此大幅度提高射线追踪过程的计算效率，解决超电大尺寸海面舰船的电磁散射计算能力问题。在构建高性能的海面舰船广义雷达散射仿真平台基础上，分析舰船目标的近场散射特性与影响因素，并针对性地模拟典型场景下的动态海面舰船近场散射模型，最终实现实际工程条件下的海面舰船目标近场散射的建模分析。.通过本项目的研究，可以拓展传统海面舰船远场散射建模与雷达特性分析，进一步为目标近场散射、导弹目标交汇等真实场景提供必要的仿真分析手段。