Three-Dimensional Target Parameter Estimation Method Based on Limited-Mode Vortex Electromagnetic Wave Radar
-
摘要: 与传统雷达系统相比,基于轨道角动量(OAM)的涡旋电磁波(VEMW)雷达为目标探测提供了额外的自由度。然而,现有大多数VEMW雷达成像与目标参数估计方法依赖大量的OAM模态,显著增加了系统的硬件成本与复杂度,同时,高阶模态的引入还会导致涡旋电磁波主瓣偏离感兴趣区域并导致系统噪声鲁棒性下降,严重限制了其在实际工程中的应用。针对上述局限性,该文提出了一种基于有限OAM模态的三维目标参数估计方法。首先,构建了VEMW雷达前视成像几何模型,利用脉冲压缩技术提取目标的距离信息。随后,构造对偶OAM模态的和差波束回波比值,利用贝塞尔函数的对称性,实现方位角信息的估计。最后,构造相邻OAM模态的回波信号比值,利用贝塞尔函数的递推性质,实现俯仰角信息的估计。进一步地,针对同一距离门内双目标场景,构造相邻OAM模态回波比值,并利用其相位差异特性,实现了同一距离门内双目标参数估计。此外,该文推导了方位角与俯仰角估计的克拉美-罗下界,并将所提闭式三维估计方法的均方根误差与理论下界进行了对比分析。数值仿真与微波暗室实验均表明,所提方法在多目标及噪声环境下能够实现可靠的三维参数估计,展现出良好的抗噪性与工程应用潜力。Abstract: Compared with traditional radar systems, the vortex electromagnetic wave (VEMW) radar based on orbital angular momentum (OAM) provides additional degrees of freedom for target detection. However, most existing VEMW radar imaging and parameter estimation methods rely on a large number of OAM modes, which significantly increases the hardware cost and complexity of the system. Moreover, the introduction of high-order modes causes the main lobe of the VEMW to deviate from the region of interest while reducing the system’s robustness to noise, severely limiting its practical engineering applications. To address these limitations, this study proposes a three-dimensional target parameter estimation method based on limited OAM modes. First, a forward-looking imaging geometric model of the VEMW radar is constructed, and pulse compression technology is used to extract the target’s range information. Subsequently, the echo ratio between the sum and difference beams of dual OAM modes is constructed, and the symmetry of the Bessel function is utilized to estimate the target’s azimuth angle information. Finally, the echo signal ratio of adjacent OAM modes is constructed, and the recurrence property of the Bessel function is used to estimate the target’s elevation angle information. Furthermore, for a dual-target scenario within the same range bin, the echo signal ratio of adjacent OAM modes is constructed, and the target parameters are estimated by exploiting the phase difference characteristics of the echoes. In addition, this paper derives the Cramér–Rao lower bound for azimuth and elevation angle estimation and compares the root mean square error of the proposed closed-form three-dimensional estimation method with the theoretical lower bound. Numerical simulations and microwave anechoic chamber experiments show that the proposed method achieves reliable three-dimensional parameter estimation in multitarget and noisy environments, thereby verifying its effectiveness and engineering feasibility.
-
表 1 本文所提参数估计方法的仿真和实测参数
Table 1. Simulation and measured parameters of the parameter estimation method proposed in this paper
参数 数值 载频$ {\text{f}}_{c} $ 36 GHz 带宽$ {B}_{r} $ 6 GHz 波长$ \lambda $ 0.0083 m半径a 6.52$ \lambda $ 发射阵元数量 16 接收阵元数量 1 OAM模态l [−2, −1, 1, 2, 3] 表 2 实验测量结果
Table 2. Experimental measurement results
目标 真实位置 场景1实验结果 场景2实验结果 1 (10.24 m, 4.2°, 117°) (10.24 m, 4.05°, 115.5°) (10.24 m, 4.9°, 119.7°) 2 (9.86 m, 7.0°, −20°) / (9.87 m, 7.6°, −20.7°) -
[1] BARNETT S M and ALLEN L. Orbital angular momentum and nonparaxial light beams[J]. Optics Communications, 1994, 110(5/6): 670–678. doi: 10.1016/0030-4018(94)90269-0. [2] LIU Kang, CHENG Yongqiang, YANG Zhaocheng, et al. Orbital-angular-momentum-based electromagnetic vortex imaging[J]. IEEE Antennas and Wireless Propagation Letters, 2015, 14: 711–714. doi: 10.1109/LAWP.2014.2376970. [3] PAPATHANASOPOULOS A and RAHMAT-SAMII Y. A review on Orbital Angular Momentum (OAM) beams: Fundamental concepts, potential applications, and perspectives[C]. 2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS), Rome, Italy, 2021: 1–4. DOI: 10.23919/URSIGASS51995.2021.9560285. [4] PADGETT M J. Orbital angular momentum 25 years on [Invited][J]. Optics Express, 2017, 25(10): 11265–11274. doi: 10.1364/OE.25.011265. [5] WEI Yixin, SHU Gaofeng, and LI Ning. Improving orbital angular momentum mode utilization with mode switching periodically in radar forward-looking imaging[J]. IEEE Signal Processing Letters, 2025, 32: 3102–3106. doi: 10.1109/LSP.2025.3593646. [6] WANG Yu, LIU Kang, LIU Hongyan, et al. High-speed moving target detection method with OAM radar[C]. 2024 IEEE MTT-S International Microwave Workshop Series on Advanced Materials and Processes for RF and THz Applications (IMWS-AMP), Nanjing, China, 2024: 1–3. DOI: 10.1109/IMWS-AMP62793.2024.10966750. [7] LIU Kang, LI Xiang, GAO Yue, et al. High-resolution electromagnetic vortex imaging based on sparse Bayesian learning[J]. IEEE Sensors Journal, 2017, 17(21): 6918–6927. doi: 10.1109/JSEN.2017.2754554. [8] TAN Zhengkuan, LIU Hongyan, LIU Kang, et al. Azimuth-elevation 2D angle estimation method with electromagnetic vortex[C]. 2025 IEEE International Workshop on Electromagnetics: Applications and Student Innovation Competition (iWEM), Hong Kong, China, 2025: 316–319. DOI: 10.1109/iWEM65640.2025.11167933. [9] SHI Zhuyu, PAN Haoran, LV Kun, et al. 3D-TF-spectrum-based rotational parameter extraction of extended target with vortex electromagnetic wave radar[C]. 2024 IEEE International Conference on Signal, Information and Data Processing (ICSIDP), Zhuhai, China, 2024: 1–6. DOI: 10.1109/ICSIDP62679.2024.10867962. [10] LU Zekai, WANG Jiale, LIAN Jie, et al. A mode-matching approach for acoustic vortex generation in circular array configurations[J]. IEEE Signal Processing Letters, 2024, 31: 1590–1594. doi: 10.1109/LSP.2024.3411510. [11] ZHOU Tianjun, HE Zhengyao, SHI Qiang, et al. Multisnapshot high-resolution gridless DOA estimation for uniform circular arrays[J]. IEEE Signal Processing Letters, 2024, 31: 1705–1709. doi: 10.1109/LSP.2024.3414373. [12] LIU Hongyan, LIU Kang, CHENG Yongqiang, et al. Microwave vortex imaging based on dual coupled OAM beams[J]. IEEE Sensors Journal, 2020, 20(2): 806–815. doi: 10.1109/JSEN.2019.2943698. [13] WANG Jianqiu, LIU Kang, WANG Yu, et al. A novel forward-looking target reconstruction method with electromagnetic vortex interferometry[J]. IEEE Transactions on Microwave Theory and Techniques, 2023, 71(12): 5428–5444. doi: 10.1109/TMTT.2023.3278947. [14] QU Haiyou, LI Shiyuan, CHEN Chang, et al. High-resolution orbital angular momentum imaging with the removal of Bessel function modulation effect[J]. IEEE Transactions on Microwave Theory and Techniques, 2024, 72(4): 2577–2590. doi: 10.1109/TMTT.2023.3314107. [15] YANG Ting, SHI Hongyin, LIU Da, et al. High-resolution vortex electromagnetic wave radar sparse imaging using efficient 2D-SLIM[J]. IEEE Transactions on Computational Imaging, 2026, 12: 614–629. doi: 10.1109/TCI.2026.3663911. [16] WANG Siyuan, LUO Ying, CHEN Yijun, et al. 3-D imaging with vortex electromagnetic wave radar based on nested array structure—part I: Sparse imaging algorithm[J]. IEEE Sensors Journal, 2025, 25(23): 42988–43002. doi: 10.1109/JSEN.2025.3590635. [17] CAI Jiazhen, GAO Xinlu, HUANG Jiajie, et al. High-resolution multimode electromagnetic vortex imaging driven by the RELAX algorithm[J]. IEEE Transactions on Antennas and Propagation, 2026, 74(4): 3250–3265. doi: 10.1109/TAP.2026.3651998. [18] 王建秋, 刘康, 王煜, 等. 涡旋电磁波雷达成像分辨力研究[J]. 雷达学报, 2021, 10(5): 680–690. doi: 10.12000/JR21054.WANG Jianqiu, LIU Kang, WANG Yu, et al. Resolution analysis of vortex electromagnetic radar imaging[J]. Journal of Radars, 2021, 10(5): 680–690. doi: 10.12000/JR21054. [19] SCHMIDT R. Multiple emitter location and signal parameter estimation[J]. IEEE Transactions on Antennas and Propagation, 1986, 34(3): 276–280. doi: 10.1109/TAP.1986.1143830. [20] ROY R and KAILATH T. ESPRIT-estimation of signal parameters via rotational invariance techniques[J]. IEEE Transactions on Acoustics, Speech, and Signal Processing, 1989, 37(7): 984–995. doi: 10.1109/29.32276. [21] LIN Mingtuan, GAO Yue, LIU Peiguo, et al. Improved OAM-based radar targets detection using uniform concentric circular arrays[J]. International Journal of Antennas and Propagation, 2016, 2016: 1852659. doi: 10.1155/2016/1852659. [22] CHEN Rui, LONG Wenxuan, GAO Yue, et al. Orbital angular momentum-based two-dimensional super-resolution targets imaging[C]. 2018 IEEE Global Conference on Signal and Information Processing (GlobalSIP), Anaheim, USA, 2018: 1243–1246. DOI: 10.1109/GlobalSIP.2018.8646368. [23] ZHANG Lingling, ZHU Yongzhong, CHEN Yijun, et al. Three-dimensional micro-Doppler parameter estimation of rotor target based on VEMW radar[J]. IEEE Sensors Journal, 2025, 25(6): 10155–10162. doi: 10.1109/JSEN.2025.3533009. [24] ZHANG Hongyun, LI Ping, and ZHANG Guangwei. Orbital angular momentum radio-wave-based 2-D target angle estimation with mutual coupling[J]. IEEE Sensors Journal, 2023, 23(6): 6169–6177. doi: 10.1109/JSEN.2023.3241006. [25] MATHEWS C P and ZOLTOWSKI M D. Eigenstructure techniques for 2-D angle estimation with uniform circular arrays[J]. IEEE Transactions on Signal Processing, 1994, 42(9): 2395–2407. doi: 10.1109/78.317861. [26] TAN Zhengkuan, LIU Kang, LIU Hongyan, et al. Object location estimation method with radar transmitting vortex electromagnetic wave[J]. IEEE Transactions on Antennas and Propagation, 2025, 73(12): 10748–10756. doi: 10.1109/TAP.2025.3611297. [27] 王勇, 刘禹锋. 单脉冲成像技术发展现状综述[J]. 雷达学报(中英文), 2026, 15(1): 307–330. doi: 10.12000/JR25057.WANG Yong and LIU Yufeng. A review of the current developments in monopulse imaging technology[J]. Journal of Radars, 2026, 15(1): 307–330. doi: 10.12000/JR25057. [28] 李悦丽, 马萌恩, 赵崇辉, 等. 基于单脉冲雷达和差通道多普勒估计的前视成像[J]. 雷达学报, 2021, 10(1): 131–142. doi: 10.12000/JR20111.LI Yueli, MA Men’en, ZHAO Chonghui, et al. Forward-looking imaging via Doppler estimates of sum-difference measurements in scanning monopulse radar[J]. Journal of Radars, 2021, 10(1): 131–142. doi: 10.12000/JR20111. [29] LIU Kang, LIU Hongyan, QIN Yuliang, et al. Generation of OAM beams using phased array in the microwave band[J]. IEEE Transactions on Antennas and Propagation, 2016, 64(9): 3850–3857. doi: 10.1109/TAP.2016.2589960. [30] KAY S M. Fundamentals of Statistical Signal Processing: Estimation Theory[M]. Englewood Cliffs: PTR Prentice-Hall, 1993: 15–77. [31] MOHAMMADI S M, DALDORFF L K S, FOROZESH K, et al. Orbital angular momentum in radio: Measurement methods[J]. Radio Science, 2010, 45(4): RS4007. doi: 10.1029/2009RS004299. -
作者中心
专家审稿
责编办公
编辑办公
下载: