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Front Matter i-xx
Executive Summary 1-1
TASK 1 2-6
Recommendations that Enhance GPS Performance for Civil and Commercial Users 7-7
Recommendations that Enhance GPS Performance for All Users (Civil, Commercial, and Military) 8-9
Improvement Implementation Strategy 10-11
TASK 3 12-12
THE TASK 13-13
JOINT STUDY APPROACH 14-14
MAJOR ISSUES AND CONSIDERATIONS 15-15
GPS PROGRAM OVERVIEW 16-16
GPS TECHNICAL OVERVIEW 17-18
INTRODUCTION 19-19
GPS MILITARY APPLICATIONS 20-20
Current and Future Applications and Requirements 21-21
Accuracy and Integrity 22-24
Anti-Jam and Anti-Spoof Capability 25-25
GPS AVIATION APPLICATIONS 26-26
Current and Future Applications and Requirements 27-29
Resistance to Radio Frequency Interference 30-30
Operational Procedures 31-31
MARITIME USE OF GPS 32-32
Current and Future Applications and Requirements 33-34
Associated Technologies 35-35
Selective Availability 36-36
Findings 37-37
Current and Future Applications and Requirements 38-40
Accuracy Versus Other Requirements 41-41
Findings 42-42
Current and Future Applications and Requirements 43-44
Challenges to Full GPS Utilization 45-45
GPS EARTH SCIENCE APPLICATIONS 46-46
Oceanography 47-47
Airborne Geophysics 48-48
Accuracy Requirements 49-49
Oceanography 50-50
Findings 51-51
Current and Future Applications and Requirements 52-54
Time Synchronization 55-55
SPACECRAFT USES OF GPS 56-56
Orbit Determination 57-57
Launch and Re-entry Vehicle Guidance 58-59
Signal Visibility 60-60
SUMMARY 61-66
INTRODUCTION 67-67
Accuracy 68-69
SELECTIVE AVAILABILITY AND ANTI-SPOOFING 70-70
Selective Availability 71-71
Military Utility of SA 72-77
Impact of SA on GPS User Equipment Manufacturers and U.S. Competitiveness 78-78
Impact of SA on Civil Users 79-81
Findings and Recommendations 82-83
Impact of A-S on Military Users 84-84
Findings and Recommendations 85-85
SIGNAL STRUCTURE MODIFICATIONS TO REDUCE ATMOSPHERIC DELAY ERROR 86-86
Guidelines and Technical Considerations 87-87
New Signal Structure Options 88-88
Option 2: Narrow-Band L4 Signal 89-89
Increased Accuracy 90-90
Reduction of Receiver Noise and Multipath Errors 91-96
Findings and Recommendations 97-97
Recommended Upgrades to the Operational Control Segment 98-98
Accuracy Improvements 99-105
Overall System Improvements 106-107
Planned Block IIR Operation 108-108
Accuracy Improvements by Incorporating Satellite Ranging Data into Ground Solution 109-109
Ground-Based Integrity Improvements 110-110
Rapid, Direct Y-Code Acquisition 111-112
Inertial Aiding Improvements 113-113
Signal Processing Improvements 114-114
Improved L2 Ionospheric Correction 115-115
Possible Interim Operational Procedures 116-116
IMPROVEMENT IMPLEMENTATION STRATEGY 117-122
Use of a 24-Satellite Ensemble Clock 123-123
Reduced Satellite Clock Errors Through Use of Improved Clocks 124-124
Satellite-Based Integrity Monitoring 125-125
Cross-Correlation Type Y-Codeless Receivers 126-126
Y-Code Tracking PPS Receivers 127-127
Wide-Band Signals at High Frequency 128-131
Spot Beams 132-132
GPS Transmit Antenna Calibration 133-133
Improved L1 Signal Reception at Angles Below the Earth's Horizon 134-138
Appendix B Abbreviated Committee Biographies 139-144
ORIGINS AND DEVELOPMENT OF THE NAVSTAR GPS PROGRAM 145-145
Department of Defense 146-146
Department of Transportation 147-147
The Federal Radionavigation Plan 148-149
GPS TECHNICAL OVERVIEW 150-150
Space Segment 151-152
Operational Control Segment 153-153
User Equipment 154-154
GPS Signal Characteristics and Operational Concepts 155-157
Selective Availability and Other Positioning Errors 158-159
Atmospheric Error 160-160
Receiver Errors 161-161
Availability 162-162
Resistance to RF Interference 163-163
Differential GPS 164-164
Carrier Phase (Interferometric) GPS 165-165
Receiver Autonomous Integrity Monitoring (RAIM) 166-166
Combined Use of GPS and GLONASS 167-167
GPS and Loran-C 168-168
PERMANENT DIFFERENTIAL GPS AUGMENTATIONS 169-169
FAA Wide-Area and Local-Area DGPS Concepts 170-170
NOAA Continuously Operated Reference Stations 171-171
Maritime DGPS Services 172-172
Inmarsat 173-173
Racal Survey 174-174
ACCQPOINT 175-175
Differential Corrections Inc. 176-176
Appendix D Accuracy Definitions And Mathematical Relationships 177-178
Appendix E Report From Mr. Michael Dyment, Booz Allen & Hamilton 179-200
Appendix F Report From Dr. Young Lee, The MITRE Corporation 201-203
EFFECT OF ELIMINATING SELECTIVE AVAILABILITY (SA): IMPACT ON RAIM 204-212
Appendix G Increased Bandwidth Performance Analysis 213-214
Appendix H Signal Structure Options 215-217
OPTION 6 218-218
OPTION 9 219-220
Appendix I Report From Mr. Melvin Barmat, Jansky/Barmat Telecommunications, Inc. 221-248
Appendix J Selective Denial of Civilian GPS Signals by the Military 249-252
OLD TECHNOLOGY (100,000 GATE ASIC) 253-253
DISCUSSION 254-254
Appendix L Enhanced Signal Structures for the Military 255-255
SCENARIO 1: UNAIDED Y-CODE BANDWIDTH SIGNAL WITH A STANDARD ANTENNA 256-256
SCENARIO 5: AIDED WIDE BANDWIDTH STANDARD ANTENNA 257-257
SCENARIO 7: AIDED WIDE BANDWIDTH WITH NULLING AND BEAM-FORMING ANTENNA 258-262
Analysis 263-263
Analysis 264-264

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The Global Positioning System: A Shared National Asset (1995)

Chapter: GPS TECHNICAL OVERVIEW

GPS Technical Overview

My Academies

The Global Positioning System: A Shared National Asset (1995)

Chapter: GPS TECHNICAL OVERVIEW

GPS Technical Overview