Understanding the GPS

French G.T.0965572307, 9780965572309

There is an ever-growing supply of information about the Global Positioning System. Unfortunately, these new (and now, some not so new) documents seem to be located at each end of the comprehension scale: either at the “gee-whiz” level which basically describes how interesting and useful this new utility is, or at the engineer’s level which starts out with Keplerian orbits and Hopfield Modeling. What seems to be missing is a comprehensive, yet easy to understand, presentation of the Global Positioning System (GPS) for people who may have a very real need to apply this new technology but lack the basic understanding necessary to make important, and often expensive, decisions about it. Thus this book. This book is designed to support an introductory course on the fundamentals of the Global Positioning System based on a series of graphic representations and distilled concept-bullets. Math is scrupulously avoided-that level of information is readily available through numerous highly technical publications and is no more necessary for most users than is a textbook on electronics necessary for the purchaser of a television set.

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Table of contents :
Back Cover……Page 0
Preface……Page 5
Errata……Page 6
Contents……Page 7
Part I – Introduction and Background……Page 10
Introduction……Page 12
Topics……Page 16
What is GPS?……Page 18
Radio-Navigation Systems……Page 20
Frequency and Precision……Page 22
Evolution of the GPS……Page 24
CPS Cicil Applications……Page 28
GPS Segments……Page 30
The Control Segment……Page 32
Control Segment Locations……Page 34
The Space Segment……Page 36
Orbits……Page 38
Launch History……Page 40
How Does GPS Work?……Page 42
Two- Way vs. One- Way Ranging……Page 44
Single Range To A Single SVKnown……Page 46
Two Ranges To Two SVs Known……Page 48
Three Ranges To Three SVs Known……Page 50
Why Four Satellites?……Page 52
No Clock Timing Error……Page 54
Receiver Time One Second Fast……Page 56
Addition Of Another SV Time/Range……Page 58
Levels Of GPS Service……Page 60
Part II – Basic Signal Structure and Error……Page 62
Basic GPS Signal Structure……Page 64
Pseudo-Random Codes……Page 68
The Code Is The Key……Page 70
Hey, Which “HEY?”……Page 72
Where Are The Satellites?……Page 74
GPS Signal Structure Map……Page 76
Signal Strength……Page 78
GPS Resolution – C/A-Code……Page 80
GPS Resolution – P-Code……Page 82
Anti-Spoofing (A/S)……Page 84
Carrier-Phase Positioning……Page 88
GPS Resolution – Carrier-Phase……Page 92
GPS Velocity……Page 94
GPS Error Budget……Page 96
Ionospheric/Tropospheric Refraction……Page 98
SV Mask Angle……Page 100
Multi-Path Errors……Page 102
Selective Availability……Page 104
Dilution of Precision (DOP)……Page 106
Project Planning……Page 114
“Condo Canyons”……Page 116
Off-Set Positions……Page 118
Mission Planning……Page 120
Almanacs……Page 126
Autonomous Accuracy……Page 128
Part III Data Correction Techniques and High-Resolution Accuracy……Page 130
Differential Correction……Page 132
Post-Processed Corrections……Page 136
Post-Processing Differential Data……Page 138
Real-Time Correction……Page 140
Real-Time Differential Data……Page 142
Post-Processing vs Real-Time……Page 144
Differential Data Sources……Page 146
CORS Network……Page 148
U.S. Coast Guard Beacons……Page 154
U.S.C.G./A.C.O.E. – Differential Radio-Beacon Coverage……Page 156
What Is W.A.A.S. ?……Page 158
Commercial Geostationary SVs……Page 160
Real-Time FM Sub-Carriers……Page 162
Predicted Coverage For FM DGPS……Page 164
Other Improvement Techniques……Page 166
Accuracy……Page 168
Error Terms……Page 170
Part IV Basic Geodesy, Data Collection Techniques and GPS Applications……Page 172
Geodetic Coordinate Systems……Page 174
Ellipsoid vs. Geoid……Page 176
WGS 84……Page 178
What’s So Special About GPS Heights?……Page 180
Geodetic Heights……Page 182
Data Collection Techniques……Page 184
Points vs. Positions……Page 188
Lines From Points……Page 190
Areas From Points……Page 192
Differential Applications……Page 194
Geographic Information Systems (GIS)……Page 196
GPS/GIS Applications……Page 198
Aerial Photo Point Control……Page 200
Satellite Imagery, GPS, and GIS……Page 202
Geographic Features……Page 204
GPS/GIS Point Data Capture……Page 206
GPS/GIS Line Data Capture……Page 208
Areas From Points……Page 210
External Data Sources……Page 212
GPS Surveying……Page 214
GPS Navigation……Page 216
IVHS……Page 218
Independent IVHS……Page 220
Fleet Management IVHS……Page 222
Advisory IVHS Systems……Page 224
Inventory IVHS Systems……Page 226
Receiver Types……Page 228
The Future of GPS……Page 230
The Future?……Page 234
Appendix I – Glossary of Terms……Page 236
Appendix II – Suggested Readings on the GPS……Page 256
About the Author……Page 264