泛用性導航定位系統之研製

Abstract

拜今日通訊技術迅速發展及網路資訊的流通便利，使得全球定位系統(GPS)已成為現今導航定位多數應用的主流。傳統上，一般採用區域性電波或慣性導航系統(INS)為主。但因GPS在長時間觀察衛星定位下有較穩定，並可利用雙重差分定位解算，增加GPS定位準確度的特性，藉以校正INS長時間操作下因累積效應所造成的誤差。另一方面，INS獨立、自主的特性，恰可彌補GPS受環境遮蔽效應及高頻雜訊、運動加速度過大而導致脫鎖的間斷現象。所以我們以此互補的特性，建構一GPS/INS複合式平面導航系統。此外，若配合其他追蹤監測系統，將可擴展其系統使用空間維度。本論文主要是針對GPS與INS之系統整合方法，進行理論分析、評比及實現架構選定。而此整合系統中之狀態處理，皆以卡門濾波器(Kalman Filter)完成。 同時，我們利用所知理論，整合商用低價位GPS/DGPS產品及INS感測元件，藉由實驗驗證整合後系統的結果，分析此一低成本、可靠允許範圍內，其複合架構產品之可能應用程度。

Owing to the technology of the communication and the network information are developed fast, such that GPS is the mainstream of the most application of the navigation system in the present day. The traditional usage of navigation systems includes the local radio-based system and INS. Because the positioning observation of GPS is with long-term stability and uses the different algorithm mode to improve the positioning accuracy as DGPS, thus the divergent effect of INS can be rectified with GPS-aiding. On the other hand, the characteristics of INS can supply the information of vehicle maneuvering, or in the duration for the lost track conditions due to receiver noises and antenna shielding effects. Therefore, both of GPS and INS are complement with each other that we can build a flat integrated navigation system, and use other monitoring systems to expand the dimension for the specific applications. In this thesis, we study the integrated approaches between GPS and INS, and the chosen structure is achieved. We use the Kalman filter to process the state variables of this hybrid system. Furthermore, we integrate the ready-made GPS/DGPS engines and the sensors of INS that can analyze its performance and advantage from the results of an experiment. ABSTRACT ACKNOWLEDGMENT TABLE OF CONTENTS LIST OF TABLES LIST OF FIGURES NOMENCLATURES 1.INTRODUCTION 1.1. Motivation 1.2. Outline 2. GLOBAL POSITIONING SYSTEM 2.1. System Overview 2.1.1. Space Segment 2.1.2. Control Segment 2.1.3. User Segment 2.2. Navigaiton Using GPS 2.2.1. The Navigation Message 2.2.2. GPS Observables 2.2.2.1. Pseudo Range 2.2.2.2. Carrier Phase 2.2.3. Position and Velocity Determination 2.2.3.1. Position Estimation 2.2.3.2. Velocity Estimation 2.3. Differential GPS 2.3.1. GPS Error Sources 2.3.2. DGPS Technique 2.3.2.1. Pseudo Range Correction 2.3.2.2. Position Correction 2.4. The Performance Evaluation of a C/A Code Receiver 3. INERTIAL NAVIGATION SYSTEM 3.1. System Overview 3.1.1. Gimballed System 3.1.2. Strapdown System 3.2. Coordinate Frames and Transformations 3.2.1. Coordinate Frame Definitions 3.2.2. ECEF Transformations 3.3. The INS Error Model Derivation 3.3.1. Quaternions 3.3.2. The Dynamic Equations 3.3.3. INS Error Models 3.4. The Performance Evaluations for the Sensors of INS 3.4.1. Accelerometer 3.4.2. Gyro and Electronic Compass Module 4. HYBRID GPS, DGPS/INS NAVIGATION SYSTEM 4.1. GPS/INS Integration Approaches 4.1.1. The Error State Space Filter Approaches 4.1.2. Coupling Approaches 4.1.2.1. Loosely Coupled Approaches 4.1.2.2. Tightly Coupled Approaches 4.2. Hybrid GPS, DGPS/INS System Design 4.3. Experiments and Results 4.3.1. Design of Road Test Experiments 4.3.2. Experiments Results 5. CONCLUSIONS AND SUGGESTIONS FOR FURTHER RESEARCH BIBLIOGRAPHY APPENDIX A. The Kalman Filter A.1. The Discrete Kalman Filter A.2. The Continuous Kalman Filter APPENDIX B. The Hybrid GPS, DGPS/INS System