计算机应用 ›› 2017, Vol. 37 ›› Issue (3): 911-914.DOI: 10.11772/j.issn.1001-9081.2017.03.911

• 应用前沿、交叉与综合 • 上一篇    

基于伪随机码调制的车载激光雷达距离速度同步测量方法

郑刚, 程用志, 毛雪松   

  1. 武汉科技大学 信息科学与工程学院, 武汉 430081
  • 收稿日期:2016-08-26 修回日期:2016-10-13 出版日期:2017-03-10 发布日期:2017-03-22
  • 通讯作者: 毛雪松
  • 作者简介:郑刚(1991-),男,湖北仙桃人,硕士研究生,主要研究方向:激光雷达信号处理;程用志(1984-),男,湖北咸宁人,讲师,博士,主要研究方向:光学与电磁超材料;毛雪松(1975-),男,江苏盐城人,教授,博士,主要研究方向:激光检测系统、非线性光纤光学、道路环境感知。
  • 基金资助:
    国家自然科学基金资助项目(61605147);湖北省自然科学基金资助项目(2014CFB815)。

Simultaneous range and speed measurement by vehicle laser radar based on pseudo-random noise code modulation

ZHENG Gang, CHENG Yongzhi, MAO Xuesong   

  1. School of Information Science and Engineering, Wuhan University of Science and Technology, Wuhan Hubei 430081, China
  • Received:2016-08-26 Revised:2016-10-13 Online:2017-03-10 Published:2017-03-22
  • Supported by:
    This work is partially supported by the National Natural Science Foundation of China (61605147), the Natural Science Foundation of Hubei Province (2014CFB815).

摘要: 针对双检测器激光雷达系统用于同步测量道路目标距离和速度时存在的成本高、回波利用效率低的问题,提出了一种基于伪随机(PN)码调制的脉冲式多普勒激光雷达结构模型,研究使用单个光外差接收器同步测量目标距离和速度的可行性并通过计算机仿真验证方法的性能。首先,给出激光雷达的系统模型,分析模型在脉冲方式下用于距离和速度测量时存在的问题;然后,讨论通过单个光外差接收器输出的电信号计算目标距离和速度的方法,即计算输出信号与本地调制码的相关函数确定激光飞行时间进而得出目标距离和使用非等间隔采样信号频谱分析方法确定输出信号的多普勒频率进而得出目标的速度;最后通过仿真验证所提出的方法可同时实现目标距离和速度的稳定检测。实验结果表明,在道路环境中该方法可实现目标距离和速度的稳定可靠测量,与直接检测系统相比,测量的灵敏度可提高10 dB以上,且与回波的到达时间、多普勒频率的大小无关。

关键词: 车载激光雷达, 伪随机码调制, 非等间隔采样, 道路信息感知, 光外差检测

Abstract: To solve the problems of high cost and low echo signal utilization efficiency in recently proposed laser radar systems integrated with double optical receivers for measuring range and speed of road targets, a pulsed Doppler laser radar system based on Pseudo-random Noise (PN) code modulation was proposed. The possibility of measuring range and speed simultaneously by the system integrated with single optical receiver was studied. The performance of the proposed method was verified by computer simulation. Firstly, the system model of vehicle laser radar was demonstrated and the existing problem for measuring range and speed by the model was analyzed when it works in pulsed mode. Then, the schematic diagram method for range and speed measurement by analyzing electric signal output from single optical heterodyne receiver was discussed, i.e. the correlation function of the electric signal and local modulation codes was computed for obtaining light flight time, and then target range; the spectrum of the electric signal was computed by non-uniformly sampled signal spectrum analysis method for obtaining Doppler frequency, and then the target speed. Finally, the stability of the proposed method for range and speed measurement was verified by computer simulation. The experimental results show that the method achieves stable range and speed measurement in road environments. Compared to direct detection system, the sensitivity of measurement is improved over 10 dB, which has no relation to echo arrival time and amount of Doppler frequency.

Key words: vehicle laser radar, pseudo-random code modulation, non-uniform sampling, road target sensing, optical heterodyne detection

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