双脉冲相干系统测距测速能力研究与优化  

Optimization of Ranging and Velocity Measurement Capability of a Double-Pulse Coherent System

作　　者：陈思 张海洋[1] 靳发宏 汪林 赵长明[1] Chen Si;Zhang Haiyang;Jin Fahong;Wang Lin;Zhao Changming(School of Optics and Photonics,Beijing Institute of Technology,Beijing 100081,China)

机构地区：[1]北京理工大学光电学院,北京100081

出　　处：《中国激光》2025年第2期98-110,共13页Chinese Journal of Lasers

基　　金：北京理工大学研究生水平和创新能力提升专项计划多学科综合交叉创新项目(2023YCXY025)。

摘　　要：双脉冲雷达因具有增加时间带宽乘积的显著优势,在多普勒雷达测距和测速领域得到了广泛应用。利用双脉冲波形原理,对相关测距、测速和噪声分析的理论模型进行优化,研究了前后脉冲间隔、脉冲周期和脉冲宽度对实际雷达性能的影响。从理论上证明了通过调整脉冲对前后脉冲之间的时间间隔能够实现对低速、高速甚至超高速运动目标的探测,展现了双脉冲相干系统的远距离测距和大范围测速能力。基于系统噪声分析建立探测系统参数与目标距离、速度等参数之间的关系,有助于选择合适的种子源和双脉冲信号发生装置,生成周期和脉冲间隔适宜的双脉冲波形。上述研究实现了被探测目标速度、距离信息与双脉冲激光雷达参数依赖性的具象化。根据以上参数,针对性地优化双脉冲相干系统的脉冲间隔等参数,基于希尔伯特变换对探测到的双脉冲信号进行相位信息解调。实验与理论结果之间的误差均小于0.25%,证明了双脉冲相干系统的高精度测速测距能力。Objective The pulse detection method obtains distance and speed information by measuring the round-trip time delay of pulsed electromagnetic waves.A balance must be reached between range and velocity resolution for pulse detection.Otherwise,a longer bandwidth pulse is required to overcome the aforementioned limitations of a single pulse.The double-pulse waveform markedly increases the time‒bandwidth product(TBP)and has a higher energy than a single pulse with the same ranging ability,which is beneficial for detecting weak signals.The double-pulse system does not require time-frequency domain conversion,which reduces computation time to some extent.Therefore,the double-pulse waveform can also be applied to vibration measurement instruments,three-dimensional coherent imaging,and detection of hard and aerosol targets using Doppler radar.We propose a double-pulse coherent detection system to prevent interference from background light.By establishing theoretical models and conducting experiments,the ranging and velocity measurements in a double-pulse coherent system were optimized.This study is expected to provide a new direction for LIDAR detection and lays a foundation for improving detection accuracy of double-pulse systems.Methods Theoretical models for ranging and velocity measurements were established to study the effects of pulse interval,width,and period on the performance of double-pulse LIDAR.The low-and high-speed targets can be measured by controlling the time interval between the front and rear pulses of a pulse pair,in theory and simulations.A mathematical model of the relationship between the parameters of the double-pulse system and characteristics of the detected target was constructed through noise analysis.Based on the above parameters,the experiment on the ranging and velocity measurements of the targets in a double-pulse coherent system was optimized by demodulating the phase information of the detected double-pulse signal using the Hilbert transform and Python software.Results and Discussions T

关 键 词：双脉冲系统 相干探测 高精度测距和测速 希尔伯特变换 

分 类 号：TN957[电子电信—信号与信息处理]