摘要
高速弹丸初速与运动姿态的精确测量是火炮、电磁炮等武器系统效能评估的关键技术。然而,复杂测试环境下的火光、烟雾及等离子体干扰导致传统光电测速技术信噪比急剧下降。为此,文中提出基于太赫兹波的新型测速方案,其兼具等离子体穿透、火光烟雾透射与电磁抗干扰特性。结合AlGaN/GaN高电子迁移率晶体管(High-Electron-Mobility Transistor,HEMT)探测器的高速响应优势,构建单光源多通道区截测速系统,采用高斯准光-泊松点定位联合建模方法,有效解决太赫兹波衍射问题。所构建系统通过单光源多通道架构设计,光学元件相比传统装置减少50%以上,结合锂电池供电与硅透镜耦合技术,实现了系统小型化与环境适应性提升。在3000 m/s弹速模拟测试中,基于线列探测器局部极大值提取与远场扩散模型修正,测速误差由>10%降低至0.83%,且在3.5~4.5 m物距范围内保持稳定。通过理论建模、数值仿真与实验验证的全链路研究,证实了该方案为电磁炮初速测量等复杂环境下高速目标的精准测速提供了新型技术方案,未来将通过高密度阵列开发、动态模型建立及真实环境实测,进一步提升系统的实时性与鲁棒性。
Objective Accurate velocity measurement of high-speed projectiles,such as those launched by electromagnetic guns or artillery systems,is essential for evaluating weapon performance in terms of range,trajectory stability,and terminal effects.Traditional photoelectric velocimetry technologies,including laser screens,radar,and highspeed photography,face severe limitations in environments with plasma,smoke,and electromagnetic interference.For instance,visible and infrared wavelengths are strongly attenuated by smoke and hightemperature backgrounds,while microwave-based systems exhibit poor plasma penetration and susceptibility to low-frequency noise.Additionally,X-ray methods,though penetrative,suffer from bulky equipment and radiation hazards.To address these challenges,this study proposes a terahertz-based velocimetry system that leverages the unique advantages of terahertz waves(0.1-10 THz),including their ability to penetrate plasma and smoke,immunity to electromagnetic interference,and non-ionizing safety.The research aims to establish a compact,high-precision measurement framework capable of operating in complex battlefield environments.Methods The proposed system integrates a single terahertz source(94 GHz)with a multi-channel AlGaN/GaN high-electron-mobility transistor(HEMT)detector array.The terahertz wave is generated by a Gunn diode and collimated using a conical horn antenna and polytetrafluoroethylene(PTFE)lens,achieving a narrow beam divergence of 0.1 mrad and a gain of 34.5 dBi(Fig.5).The detector array comprises 50 pixels with a 3 mm pitch and 110 GHz sensitivity,designed with silicon lens-coupled non-symmetric dipole antennas to enhance signal capture efficiency.A hybrid Gaussian quasi-optical-Poisson point positioning(GQ-PPP)algorithm is developed to resolve terahertz diffraction effects and beam divergence.This algorithm processes the"W"-shaped voltage response generated by the detector array,identifying local maxima(Poisson points)within filtered signal intervals through Savitzky-Golay filtering and arithmetic averaging(Fig.3,Fig.7(c)).The system’s compact architecture reduces optical components by 50%through a single-source multi-channel illumination strategy,supported by lithium battery power and modular signal processing units to minimize environmental interference.Experimental validation combines numerical simulations—modeling Gaussian beam propagation and diffraction effects(Fig.2,Fig.4)—with laboratory tests using a motor-driven aluminum foil target to replicate 3000 m/s projectile motion under controlled conditions.Results and Discussions The GQ-PPP algorithm effectively suppresses terahertz diffraction,enabling precise time-stamp extraction from the"W"-shaped voltage response(Fig.3).Geometric correction for beam divergence,derived from Gaussian beam propagation theory(Eq.11),reduces velocity errors from>10%to 0.83% at 3000 m/s(Tab.1).Laboratory tests demonstrate corrected velocities with a maximum error of 0.288% across a 3.5-4.5 m measurement range(Tab.1).The system achieves 0.1 mrad beam collimation and a 40% volume reduction compared to conventional laser-based setups(Fig.5).Key innovations include the integration of terahertz penetration capabilities with high-speed HEMT detectors and the miniaturized architecture,resolving the traditional trade-off between beam collimation and energy density.Error analysis identifies spatial misalignment(e.g.,±0.1 mm detector pitch error contributing 0.167% velocity error)and beam divergence calibration as primary error sources.These errors are mitigated through high-frequency sampling(10 MHz),adaptive signal filtering,and laser-assisted alignment techniques.The system’s robustness is further validated through repeated experiments,showing an average relative error of 0.83%under varying propagation distances and target size.The terahertz wave’s longer wavelength(3.2 mm)inherently reduces sensitivity to small-scale environmental disturbances,while the HEMT detector’s pW-level sensitivity ensures reliable signal detection even in low-power scenarios.Conclusions This study establishes a robust terahertz interception velocimetry framework for high-speed projectile measurement in complex environments.By combining terahertz wave advantages,HEMT detector arrays,and the GQ-PPP algorithm,the system achieves sub-1%velocity errors,outperforming traditional photoelectric methods in terms of penetration,accuracy,and portability.The compact design,enabled by singlesource multi-channel architecture and lithium battery power,demonstrates significant potential for field deployment.Future work will focus on high-density detector arrays to improve spatial resolution,FPGA-based real-time processing for dynamic target tracking,and field testing under realistic battlefield conditions to validate practical reliability.These advancements position terahertz velocimetry as a transformative technology for military and industrial applications requiring high-precision measurements in adverse environments.
作者
陈彪
张金峰
孙建东
秦华
CHEN Biao;ZHANG Jinfeng;SUN Jiandong;QIN Hua(Key Laboratory of Nanodevices and Applications,Suzhou Institute of Nano-Tech and Nano-Bionics,Chinese Academy of Sciences,Suzhou 215123,China;School of Physical Science and Technology,ShanghaiTech University,Shanghai 201210,China)
出处
《红外与激光工程》
北大核心
2025年第8期190-199,共10页
Infrared and Laser Engineering
基金
国家重点研发计划项目(2024YFA1208502)
国家自然科学基金项目(U24A20227)
江苏省基础研究计划项目(BK20243028)
苏州市科技计划项目(SYC2022090)。
作者简介
陈彪,男,硕士生,主要研究方向为太赫兹测速系统;通讯作者:秦华,男,教授,博士生导师,博士,主要研究方向为固态太赫兹器件及其系统应用。
