星载雷达遥感海洋学的高性能仿真：应用于测高场景
High Performance Simulation of Spaceborne Radar for Remote-Sensing Oceanography: Application to an Altimetry Scenario
AI总结：
本文介绍了一种面向卫星海洋学的星载雷达模拟器的高性能实现，利用GPU计算并基于距离门内瞬时多普勒谱变化缓慢的假设提出快速模拟模式，大幅降低计算成本，并通过Sentinel-3 SRAL雷达高度计案例验证了模拟数据的有效性，实现了显著的速度提升。
摘要：
本文详细介绍了我们为卫星海洋学设计的星载雷达模拟器的高性能实现。我们的软件模拟海面和信号，尽可能从最低层机制开始模拟测量过程。在此视角下，原始数据被计算为许多被照射散射体的总和，其随时间变化的特性与表面粗糙度、地形和运动学相关。为了实现高效性能，我们大量使用GPU计算。此外，我们提出了一种快速模拟模式，其假设是距离门内的瞬时多普勒谱在比脉冲重复间隔（PRI）大得多的时间尺度上变化。因此，海面可以以远低于脉冲重复频率（PRF）的频率进行更新，从而大幅降低计算成本。当表面更新时，计算所有距离门的多普勒谱。然后通过一维逆傅里叶变换获得信号段，并进行加权以确保表面更新之间的平滑时间演变。我们使用Sentinel-3 SRAL仪器的雷达高度计模拟案例验证了这种快速模拟模式，表明模拟的原始数据可以使用最先进的算法进行聚焦和检索。最后，我们表明，使用适中的硬件配置，我们的模拟器可以在一天内生成足够的数据来计算场景的有效波高（SWH）和海面高度（SSH）谱。这证明我们实现了重要的最先进速度提升。
英文摘要：
In this paper, we detail the high-performance implementation of our spaceborne radar simulator for satellite oceanography. Our software simulates the sea surface and the signal to imitate, as far as possible, the measurement process, starting from its lowest level mechanisms. In this perspective, raw data are computed as the sum of many illuminated scatterers, whose time-evolving properties are related to the surface roughness, topography, and kinematics. To achieve efficient performance, we intensively use GPU computing. Moreover, we propose a fast simulation mode based on the assumption that the instantaneous Doppler spectrum within a range gate varies on a timescale significantly larger than the PRI. The sea surface can then be updated at a frequency much smaller than the PRF, drastically reducing the computational cost. When the surface is updated, Doppler spectra are computed for all range gates. Signals segments are then obtained through 1D inverse Fourier transforms and pondered to ensure a smooth time evolution between surface updates. We validate this fast simulation mode with a radar altimeter simulation case of the Sentinel-3 SRAL instrument, showing that simulated raw data can be focused and retrieved using state-of-the-art algorithms. Finally, we show that, using a modest hardware configuration, our simulator can generate enough data in one day to compute the SWH and SSH spectra of a scene. This demonstrate that we achieved an important state-of-the-art speed-up.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
