| 引用本文: | 钟 俊， 徐凡丁， 曾 琦， 刘 星. 一种基于FRFT的宽带LFM信号角度距离估计算法[J]. 雷达科学与技术, 2025, 23(4): 367-374.[点击复制] |
| ZHONG Jun, XU Fanding, ZENG Qi, LIU Xing. An Angle⁃Range Estimation Algorithm for Wideband LFM Signal Based on Fractional Fourier Transform[J]. Radar Science and Technology, 2025, 23(4): 367-374.[点击复制] |
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| 摘要: |
| 传统的超分辨测角测距算法是将子空间分解算法从角度维拓展到距离维，面向窄带信号进行多维参数估计，计算复杂度高，在低信噪比和低快拍数条件下性能不佳。本文针对宽带线性调频信号（ Linear Frequency Modulation, LFM）提出一种基于分数阶傅里叶变换的角度距离估计算法。首先利用LFM信号在分数阶傅里叶域上的能量聚集特性，推导出各阵元接收数据在分数阶傅里叶域上的修正峰值位置与阵元位置的线性关系，采用批量梯度下降法进行斜率拟合求得角度估计值，接着利用发射信号与阵列接收信号的时延关系求得距离估计值。通过估计的均方根误差与复杂度分析，与传统算法进行了对比，实验结果显示在低信噪比和低快拍数情况下本文算法估计效果优于传统算法，证明了所提算法的优异性能。 |
| 关键词: 角度距离估计 分数阶傅里叶变换 峰值位置 斜率拟合 |
| DOI：DOI:10.3969/j.issn.1672-2337.2025.04.002 |
| 分类号:TN911.7 |
| 基金项目:四川省科技计划项目（No.2023NSFSC0480） |
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| An Angle⁃Range Estimation Algorithm for Wideband LFM Signal Based on Fractional Fourier Transform |
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ZHONG Jun, XU Fanding, ZENG Qi, LIU Xing
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College of Electrical Engineering, Sichuan University, Chengdu 610065, China
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| Abstract: |
| The traditional super?resolution angle?range estimation algorithm extend the subspace decomposition method from the angle dimension to the distance dimension, and performs multi?dimensional parameters estimation for narrowband signal. It has high computational complexity and poor performance under low signal?to?noise ratio and low snapshots. This paper proposes an angle?range estimation method for wideband linear frequency modulation （LFM） signals based on fractional Fourier transform（FRFT）. The linear relationship between the modified peak position of the received data from different array elements in the fractional Fourier（FRF） domain and the array elements’ position is initially derived by using the energy aggregation characteristics of the LFM signal in FRF domain. The angle estimate value is obtained by slope fitting through the batch gradient descent method, and then the distance estimation value is obtained by using the time delay relationship between the transmitted signal and the received signal. The root mean square error and complexity of the proposed method are compared with the traditional algorithms. Experimental results demonstrate superior performance of the proposed algorithm compared with the traditional methods under low signal?to?noise ratio and low number of snapshots. |
| Key words: angle⁃range estimation fractional Fourier transform peak position slope fitting |
