测绘学报 ›› 2018, Vol. 47 ›› Issue (8): 1148-1159.doi: 10.11947/j.AGCS.2018.20170466

• 海洋测量 • 上一篇    下一篇

一种由粗到精的机载激光测深信号检测方法

王丹菂1,2, 徐青1,2, 邢帅1,2, 林雨准1, 李鹏程1   

  1. 1. 信息工程大学地理空间信息学院, 河南 郑州 450052;
    2. 近地面探测技术重点实验室, 江苏 无锡 214000
  • 收稿日期:2017-08-25 修回日期:2018-01-27 出版日期:2018-08-20 发布日期:2018-08-22
  • 通讯作者: 徐青 E-mail:1393716139@139.com
  • 作者简介:王丹菂(1993-),女,硕士生,研究方向为机载激光雷达测深技术。E-mail:wdd_93@163.com
  • 基金资助:
    国家自然科学基金(41371436);近地面探测技术重点实验室基金(TCGZ2017A008);地理信息工程国家重点实验室开放基金(SKLGIE2016-M-3-1)

A Coarse-to-fine Signal Detection Method for Airborne LiDAR Bathymetry

WANG Dandi1,2, XU Qing1,2, XING Shuai1,2, LIN Yuzhun1, LI Pengcheng1   

  1. 1. Information Engineering University, Zhengzhou 450052, China;
    2. Science and Technology on Near-Surface Detection Laboratory, Wuxi 214000, China
  • Received:2017-08-25 Revised:2018-01-27 Online:2018-08-20 Published:2018-08-22
  • Supported by:
    The National Natural Science Foundation of China (No. 41371436);The Foundation of Science and Technology on Near-Surface Detection Laboratory (No. TCGZ2017A008);The Open Research Foundation of State Key Laboratory of Geo-information Engineering (No. SKLGIE2016-M-3-1)

摘要: 针对机载激光测深(airborne lidar bathymetry,ALB)中不同环境下波形的差异性较大,且信号检测精度受限于系统采样间隔等问题,提出一种由粗到精的机载激光测深信号检测方法。该方法首先利用接收波形的有效长度快速估计水深;粗检测依据水深近似值,分别采用理查德森-露西去卷积法(Richardson-Lucy deconvolution,RLD)和平均差方函数法(average square difference function,ASDF)对波形预处理,通过包含距离、导数和极值约束的逐级检测确定信号的初始位置;精检测以粗检测结果为初值,利用改进的二阶多项式指数函数模型,并在模型参数求解中引入信赖域优化算法以实现波形的精确拟合,进而获得信号的精确位置。实测数据和模拟数据的试验结果表明,粗检测能够根据波形的特点采取相应的处理方式为精检测提供可靠的初值;精检测可将检测结果精确至子采样间隔并在粗检测基础上进一步提高精度。与极大值检测、ASDF、RLD和四边形拟合法等传统方法相比,本文方法正确率平均提高10%左右,精度平均提高约30%。

关键词: 激光雷达, 机载激光测深, 信号检测, 波形分解, 信赖域优化

Abstract: To solve the problems that waveforms vary with different environments and detection accuracy is limited by the sampling interval of airborne LiDAR bathymetry (ALB) system,a coarse-to-fine signal detection method for ALB is proposed.The effective length of the received waveform is first calculated from the system transmit signal parameters as an approximation of water depth.For the coarse detection,the received waveform is preprocessed based on Richardson-Lucy deconvolution (RLD) and average square difference function (ASDF),determined by the approximation of water depth,and through a constrained detection method signals are detected from the preprocessed waveform as the initial values of the accurate detection.In the accurate detection,an improved exponential function with a second-order polynomial model is proposed to fit the received waveform and trust region algorithm is introduced to solve the model parameters.Thus,the exact positions of the signals are obtained.The experimental results show that the coarse detection can cope with the waveforms appropriately based on these characteristics and acquire reliable results.The detection results are accurate to subsampling interval and the accuracy of the coarse detection results is further improved by the accurate detection.Compared to the traditional methods including maximum detection,ASDF,RLD and quadrilateral fitting,the success rate and the accuracy of the proposed method averagely achieve nearly 10% and 30% improvement respectively.

Key words: LiDAR, airborne LiDAR bathymetry, signal detection, wave decomposition, trust region algorithm

中图分类号: