第21卷第3期 2013年3月
文章编号
1004-924X(2013)03-081308
光学精密工程
Optics and Precision Engineering
Vol.21No.3
Mar.2013
系统参数对激光测高仪海洋测距和回波脉宽影响
马跃，李松，周辉，易洪（武汉大学电子信息学院，湖北武汉430060）
摘要：星载激光测高仪的回波时间重心和脉冲宽度等系统参数对常见海态条件下的测距和反演精度有重要影响。本文根据菲涅尔衍射理论、海洋表面镜面反射理论、海洋波高和斜率统计特性以及激光测高仪回波误差理论，推导并更正了激光测高仪海洋回波光子数表达式。首次完整推导出了影响海洋回波重心和脉宽因素的表达式，证明了回波参数主要受发射脉冲宽度、测量天底角、指向角抖动和海洋表面上方风速的影响。除风速为表面特性影响外，其余为系统参数影响。结合地球科学激光测高系统(GLAS)参数对其海洋回波的测距和脉宽精度做了定量分析，得出不同风速GLAS的海洋表面单回波测距误差为2～15cm，脉宽标准差为0.5～3.5ns。推导结果对优化设计用于海洋表面测量的星载激光测高仪系统参数、提高回波反演目标特性精度很有意义，
关键调：激光速感，激光测高仅；激光测距；国波脉宽；海洋表面模型；地球科学激光测高系统
中图分类号：P237;TH761,3
文献标识码：A
doi;10. 3788/OPE, 20132103. 0813
Effect of system parameters on ranging and pulse width
inoceansatellitelaseraltimetersystem
MAYue,LI Song',ZHOUHui,YIHong
(SchoolofElectronicInformation,WuhanUniversity，Wuhan430079,China）
Correspondingauthor，E-mail:wuhanpeople@126.com
Abstract: The system parameters such as the centroid and pulse width of a laser altimeter system have great effects on its accuracy in ranging and inversion under the condition of a common sea state. Therefore, this paper deduces the functions referred to influencing factors of centroid and pulse width and corrects the received photon function of ocean surface according to the theory of Fresnel diffrac tion, the character of specular reflection, the statistical regularity of ocean surface profile and the er ror theory of laser altimeter systems.It gives complete influencing factors on the centroid and pulse width, which include the transmitted and received instruments, nadir angles, pointing jitters and wind speeds. Among them, the first three factors are all system parameters, and the wind speed is a sur face characteristic. Combined with the parameters of Geoscience Laser Altimeter System)GLAS, the error of range and the accuracy of pulse width are calculated and analyzed, The results show that the ranging error of GLAS is from 2 to 15 cm, and that of the pulse width is from 0. 5 to 3. 5 ns under dif ferent wind speeds. The obtained conclusion is significant for the design and accuracy analysis of ocean
收稿日期：2012-11-16；修订日期：2013-01-08.
基金项目：国家"十二五”民用航天预先研究资助项目；国家自然科学基金资助项目（No，40901165)；中央高校基本
科研业务费专项资金资助项目（No.274805，No.274470，No,274473）