Department of Electronic Science, National University of Defense Technology, Changsha 410000, Hunan, China.
Sensors (Basel). 2018 Aug 23;18(9):2773. doi: 10.3390/s18092773.
Micro-motion dynamics produce Micro-range (m-R) signatures which are important features for target classification and recognition, provided that the range resolution of radar signal is high enough. However, dechirping the echo with reference measured by narrow bandwidth radar would generate the residual translational motion, which exhibits as random shifts of envelopes of range profiles. The residual translational motion would destroy the periodicity of m-R signatures and make a challenge to estimate rotational parameter. In this work, we proposed an efficient high-resolution range profile (HRRP)-based method to estimate rotational parameter, in which online measured reference distances are used to dechirp the radar raw echo. Firstly, the deduction for the modified first conditional comment of range profiles (MFCMRP) is introduced in detail, and the MFCMRP contain periodic and random components when dechirped by measured reference, corresponding to the rotational motion and the reference measured errors compared with actual reference. Secondly, the Wavelet Transform (WT) is utilized to separate the measured errors from the MFCMRP. The estimations of measured errors are used to compensate the MFCMRP, and then autocorrelation is performed on the estimated periodic component to obtain the estimation of rotational period. Lastly, the rotational amplitudes and phases are achieved by inverse Radon transform (IRT) of the compensated HRRP. The effectiveness of the proposed method in this paper is verified by synthetic data and measured radar data.
微运动动力学产生微范围 (m-R) 特征，这些特征对于目标分类和识别很重要，前提是雷达信号的距离分辨率足够高。然而，用窄带宽雷达参考测量来解斜回波会产生残余平移运动，表现为距离剖面包络的随机移动。残余平移运动会破坏 m-R 特征的周期性，给估计旋转参数带来挑战。在这项工作中，我们提出了一种高效的基于高分辨率距离像 (HRRP) 的方法来估计旋转参数，其中在线测量的参考距离用于解斜雷达原始回波。首先，详细介绍了修改后的距离像第一条件注释 (MFCMRP) 的推导，当用测量的参考解斜时，MFCMRP 包含周期性和随机分量，分别对应于旋转运动和与实际参考相比的参考测量误差。其次，利用小波变换 (WT) 将测量误差从 MFCMRP 中分离出来。测量误差的估计用于补偿 MFCMRP，然后对估计的周期性分量进行自相关，以获得旋转周期的估计。最后，通过补偿后的 HRRP 的逆拉东变换 (IRT) 获得旋转幅度和相位。本文提出的方法的有效性通过合成数据和测量雷达数据得到了验证。
