一个新的,高效的算法用于地下雷达成像下一个非平面表面.
Ingrid Ullmann1, Martin Vossiek1
1Institute of Microwaves and Photonics, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany.
Sensors (Basel, Switzerland)
|November 25, 2023
概括
这项研究引入了一个新的雷达成像概念,用于复杂的地下环境. 它通过结合空间和波数域 (k-space) 重建方法来提高不规则形状对象的计算效率.
科学领域:
- 雷达成像 雷达成像
- 电磁波传播 电磁波传播
- 信号处理 信号处理
背景情况:
- 经典的雷达成像通常假设自由空间传播,这对于像地面穿透雷达 (GPR) 或非破坏性测试 (NDT) 这样的应用是不够的.
- 在多材料背景下进行地表图像重建是复杂的,空间域方法 (例如,后置投影) 对非平面对象来说是计算密集的.
- 波数域 (k-空间) 重建对于平面表面是有效的,但许多现实世界的场景涉及部分平面几何.
研究的目的:
- 开发一种新的雷达成像概念,以高效地重建部分平面的地下物体.
- 为了利用复杂几何体的k空间重建的计算优势.
- 为了提高地下成像对不规则形状的目标的整体计算效率.
主要方法:
- 引入了一个新概念,叠加子图像,在波数域 (k空间) 中尽可能重建.
- 开发了一个细分方案,以识别适用于k空间重建的图像部分.
- 该方法使用单静态合成光圈雷达 (SAR) 和多输入多输出 (MIMO) 雷达数据进行验证.
主要成果:
- 拟议的算法有效地通过结合k空间和空间域技术来重建部分平面.
- 分段方案成功地确定了不同图像部分的最佳重建域.
- 实验结果表明,在成像不规则形状几何形状的计算效率显著增加.
结论:
- 新的基于k空间的方法为复杂几何形状的地下雷达成像计算效率提供了显著的改进.
- 这种方法为部分平面场景提供了传统空间域算法更有效的替代方案.
- 这些发现适用于各种需要地下分析的雷达成像应用.
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