Clutter Suppression Method for Short Range Slow Moving Target Detection
-
摘要: 针对强杂波环境下近距慢速运动目标检测问题,该文提出一种基于相位编码及子空间投影的杂波抑制方法。主要对周期探测信号调制Chirp相位编码,通过回波慢时间维解码使杂波近似白化,降低杂波与目标回波相关性,再依据白化后杂波及有用信号成分自相关性差异分离出信号和杂波干扰子空间;最后将接收信号投影至正交于杂波子空间的信号子空间来抑制杂波。由于该方法中杂波空间的构建不需要假设杂波模型,避免了模型假设与实际环境不匹配的问题。仿真结果和实测数据处理结果证明该方法在低信杂比条件下性能明显优于传统方法。Abstract: This paper proposes a method of clutter suppression based on phase encoding and subspace projection for close slow-moving target detection in strong clutter environment. In the framework, the periodic detection signal is modulated with phase encoding, and the clutter is whitened through echo decoding of the slow-time dimension to reduce the correlation between clutter and target echo. Furthermore interference subspace is constructed on the basis of the autocorrelation differences between whitened clutter and useful signal components. The receiving signal is projected to the signal subspace orthogonal to the clutter subspace for clutter suppression. Since the construction of clutter space does not need to assume the clutter model, it avoids the problem of mismatch between the model hypothesis and the actual environment. Simulation results and real data processing results show that this method has better performance than conventional methods under low signal-to-clutter ratio.
-
Key words:
- Clutter suppression /
- Slow-moving target /
- Phase encoding /
- Subspace projection
-
表 1 雷达系统仿真参数取值表
参数 数值 信号带宽 60 MHz 载波频率 2.45 GHz Chirp时长 2 μs 脉冲积累数目 200 IQ采样频率 60 MHz 脉冲重复周期 2 ms -
LI C Z, PENG Z Y, HUANG T Y, et al. A review on recent progress of portable short-range noncontact microwave radar systems[J]. IEEE Transactions on Microwave Theory&Techniques, 2017, 65(5): 1692–1706 doi: 10.1109/TMTT.2017.2650911 HYUN E, JIN Y S, and LEE J H. A pedestrian detection scheme using a coherent phase difference method based on 2D range-Doppler FMCW radar[J]. Sensors, 2016, 16(1): 124–137 doi: 10.3390/s16010124 TAKAHASHI R, HIRATA K, HARA T, et al. Coherent integration with null constraint on clutter spectrum for pulse Doppler radar[C]. IEEE Radar Conference, Atlanta, USA, 2012: 0068–0073. MARK J W and WOODS H A. A recursive digital MTI radar filter[J]. Proceedings of the IEEE, 1972, 60(6): 728–729 doi: 10.1109/PROC.1972.8736 XIE Wenchong, ZHAO Guolin, SHAO Yinbo, et al. Ground moving target detection technique for airborne fire-control radar[C]. International Congress on Image and Signal Processing, Hangzhou, China, 2014: 1588–1592. ROY A and MITRA D. Multi-target trackers using cubature Kalman filter for Doppler radar tracking in clutter[J]. IET Signal Processing, 2016, 10(8): 888–901 doi: 10.1049/iet-spr.2015.0540 陈小龙, 关键, 于晓涵, 等. 基于短时稀疏时频分布的雷达目标微动特征提取及检测方法[J]. 电子与信息学报, 2017, 39(5): 1017–1023 doi: 10.11999/JEIT161040CHEN Xiaolong, GUAN Jian, YU Xiaohan, et al. Radar micro-Doppler signature extraction and detection via short-time sparse time-frequency distribution[J]. Journal of Electronics&Information Technology, 2017, 39(5): 1017–1023 doi: 10.11999/JEIT161040 罗兴旺, 张伯彦, 刘嘉, 等. 雷达数据处理中的杂波抑制方法[J]. 系统工程与电子技术, 2016, 38(1): 37–44 doi: 10.3969/j.issn.1001-506X.2016.01.07LUO Xingwang, ZHANG Boyan, LIU Jia, et al. Researches on the method of clutter suppression in radar data processing[J]. Systems Engineering and Electronics, 2016, 38(1): 37–44 doi: 10.3969/j.issn.1001-506X.2016.01.07 LIM H S, JEONG S H, and LEE K H. Rejection of road clutter using mean-variance method with OS-CFAR for automotive applications[C]. International Conference on Electrical and Control Engineering, Yichang, China, 2011: 4886–4889. VERMA P K, GAIKWAD A N, SINGH D, et al. Analysis of clutter reduction techniques for through wall imaging in UWB range[J]. Progress in Electromagnetics Research B, 2009, 17: 29–48 doi: 10.2528/PIERB09060903 COLONE F, O’HAGAN D W, LOMBARDO P, et al. A multistage processing algorithm for disturbance removal and target detection in passive bistatic radar[J]. IEEE Transactions on Aerospace&Electronic Systems, 2009, 45(2): 698–722 doi: 10.1109/TAES.2009.5089551 CARDINALI R, COLONE F, FERRETTI C, et al. Comparison of clutter and multipath cancellation techniques for passive radar[C]. IEEE Radar Conference, Boston, USA, 2007: 469–474. ABUJARAD F, NADIM G, and OMAR A. Clutter reduction and detection of landmine objects in ground penetrating radar data using singular value decomposition (SVD)[C]. International Workshop on Advanced Ground Penetrating Radar, Delft, 2005: 37–42 HOU Shujie, QIU R, BROWNING J P, et al. Target detection with linear and kernel subspaces matching in the presence of strong clutter[C]. IEEE Radar Conference, Atlanta, USA, 2012: 0372–0376. TIVIVE F H C, BOUZERDOUM A, and AMIN M G. A subspace projection approach for wall clutter mitigation in through-the-wall radar imaging[J]. IEEE Transactions on Geoscience and Remote Sensing, 2014, 53(4): 2108–2122 doi: 10.1109/TGRS.2014.2355211 TANG Hui, WAN Xianrong, and KE Hengyu. Signal detection in clutter and noise using well-characterized subspace[J]. IEEE Signal Processing Letters, 2017, 24(9): 1343–1347 doi: 10.1109/LSP.2017.2731782