一个用于空中SAR的低功率VHF收发器,采用使用 chirped信号处理的增强埋藏物体检测
Yasser Siddik1,2, Khalid F A Hussein3, Hamada Esmaiel2
1Electronics and Communications Department, Akhbar El Yom Academy , Cairo, Egypt.
Scientific reports
|January 26, 2026
概括
这项研究引入了一种针对空中雷达的优化波形,通过提高信号清晰度和减少干扰来增强地下道的检测. 新方法为地下结构提供了更好的高分辨率成像.
科学领域:
- 地质物理学 地质物理学
- 雷达工程 雷达工程
- 信号处理 信号处理
背景情况:
- 合成孔径雷达 (SAR) 系统需要先进的信号处理来进行高分辨率的地下成像.
- 检测像道这样的浅层埋藏结构是具有挑战性的,因为有限的带宽和空中SAR的地面透限制.
研究的目的:
- 为低功率空载SAR系统开发和评估一个优化的非线性频率调制 (NLFM) 波形.
- 通过提高成像分辨率和目标对比度来提高埋在浅处的结构,特别是地下道的检测能力.
主要方法:
- 设计了一种采用粒子群优化 (PSO) 优化的断片线性非线性频率调制 (PWL-NLFM) 声波形.
- 通过调整PWL段的数量,共同将侧叶水平降到最低,并保持脉冲压缩比.
- 进行了定量评估和二维 (范围-阿齐木斯) 点-目标模拟,以评估波形性能.
主要成果:
- 与标准LFM和二次NLFM脉冲相比,优化的PWL-NLFM波形显著降低了峰值侧叶水平比率 (PSLR) 至-33.0 dB,并改善了整合侧叶比率 (ISLR) 至-21.8 dB.
- 模拟显示了优异的SAR聚焦,具有更清洁,更孤立的主叶,增强了地下目标和杂乱之间的对比度.
- 通过增强的二维响应,证明了道特征的改进可检测性.
结论:
- 优化的PWL-NLFM波形有效地解决了VHF频段空中SAR的带宽限制,用于高分辨率的地下成像.
- 开发的波形适用于低功耗,基于软件定义无线电 (SDR) 的SAR收发器,用于长时间任务,需要深入透和高对比度的埋藏结构成像.
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