基于射频GNSS信号模拟器和接收机的二态陆地移动卫星信道模型实现与分析

摘要

In this thesis,a two-state Land Mobile Satellite channel model is implemented and integrated to a NCS(Navigation Constellation Simulation)RF simulator to realize the function to simulate a land mobile satellite channel for a moving receiver or receivers in the simulator.Firstly the introduction to GNSS simulation is given,following a short review on the Land Mobile Satellite channel model.A detailed description on the Two-state LMS and its parameter databases are presented theoretically.The developed model is based on the ESA MiLADY LMS model,however,some modifications are made and the model is rearranged to adapt it to the real simulation situation in a NCS RF simulator.After implementation and integration,the result analysis are taken in both GSPF and NCS,showing the simulation result is realistic and the statistical results are with the expected range.Simulation results for systems:GPS,Galileo,GLONASS and BeiDou each for environment types:Urban,Suburban,Open and Forest are presented in the thesis.However,the model still has its limitations,discussion on this is presented in the end of the thesis.

目录

声明

Abstract

Acknowledgements

Table of contents

1 Introduction

1．1 Introduction to GNSS Simulation

1．1．1 What iS GNSS Simulation

1．1．2 Work Principle of GNSS Simulation

1．1．3 Walker Constellation

1．2 Motivation and Objectives

1．3 Structure of the Thesis

2 Land Mobile Satellite Channel Model

2．1 Introduction to Land Mobile Satellite Model

2．2 A Short Review on LMS Model Studies

2．2．3 Statistical LMS Model

2．2．4 Hybrid LMS Model

2．3 Two-state LMS Model

2．3．1 Fundamentals of Two-state LMS Model

2．3．2 State Modeling in Two-state LMS Model

2．3．3 Single-reception and Multi-reception in LMS Model

2．4 ESA LMS Model from MILADY Project

3 Implementation Environment

3．1．1 The GSPF Architecture

3．1．2 The Configuration Framework

3．2 Navigation Constellation Simulator(NCS)

4 Methodology

4．1 Adapted Algorithm Design

4．1．1 Disagreements with“Static’’LMS Modelling

4．1．2 Adapted Algorithm to Ensure the“Dynamic’’State Modelling

4．1．3 Structure of the Parameter Database

5 Results and Analysis

5．1 Master Satellite Parameter Comparison

5．1．1 Different Master Satellite Elevation

5．1．2 Different Master Satellite Azimuth

5．2 Simulated GNSS signals in LMS model

5．2．1 Simulated GPS LMS Channel Signals

5．2．2 Simulated Galileo LMS Channel Signals

5．2．3 Simulated GLONASS LMS Channel Signals

5．2．4 Simulated BeiDou LMS Channel Signals

5．3 Statistical Analysis on the Model

5．4 Influence on Receiver Positioning Accuracy

6 Conclusion and Future Work

List of Abbreviations

Appendix

References