完整波形分析對於提升空載光達系統定位精度之研究

Full Waveform Analysis for Refining Positioning Accuracy of Airborne LiDAR Systems

王滙智(Hui-Zhi Wang)

指導教授 ： 趙鍵哲

國立臺灣大學/工學院/土木工程學研究所/碩士(2007年)

https://doi.org/10.6342/NTU.2007.02748

摘要

完整波形分析是未來空載光達系統的選項之一，由於其記錄著雷射光波與地物表之反射作用，倘搭配合適的波形處理及時間點偵測模式，對於場景解析及精確之幾何定位均有所助益。本研究設計空載光達系統幾何定位與完整波形模擬器，可有效模擬空載光達系統並產生回波波形作為實驗資料。本研究主要目的為針對各種時間點偵測方式測試分析完整波形光達系統之優勢，除此之外並探討完整波形處理的方法包括波形預處理、多重疊波分解與光達點位座標萃取。並輔以模擬實驗證明藉由完整波形分析可以獲得較準確的建物邊緣線上之點座標。

關鍵字

完整波形 ； 空載光達系統 ； 完整波形模擬器 ； EM演算法 ； 高斯混和模型 ； 系統誤差

並列摘要

Full waveform analysis has been becoming one of the options for airborne LIDAR systems. Due to having the complete echo of laser pulse on the surface/object it hits, the detailed scene interpretation as well as the precise positioning performance can be expected if waveform processing and timing determination are to be well considered. Therefore, a geometric positioning and a full waveform simulator are designed in this study to generate the full echo of a laser pulse together with its geometric parameters. By using these two simulators, the author demonstrates the impacts of employing different algorithms of timing determination on the positioning accuracy. In addition, waveform processing, mainly on pre-processing and multi-waveform decomposition, and precise position determination are deeply investigated. The experiments reveal that the more precise position of the building boundary can be obtained by means of the proposed full waveform analysis as compared to the traditional one that does not include this function.

並列關鍵字

full waveform ； airborne LiDAR system ； full waveform simulator ； EM algorithm ； Gaussian Mixed Model ； system error

參考文獻

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