A software-defined GPS and galileo receiver a single-frequency approach

Satellite navigation receivers are used to receive, process, and decode space-based navigation signals, such as those provided by the GPS constellation of satellites. There is an increasing need for a unified open platform that will enable enhanced receiver development and design, as well as cost-effective testing procedures for various applications. This book provide hands-on exploration of new technologies in this rapidly growing field.

One of the unique features of the work is the interactive approach used, giving readers the ability to construct their own Global Navigation Satellite Systems (GNSS) receivers. To construct such a reconfigurable receiver with a wide range of applications, the authors discuss receiver architecture based on software-defined radio (SDR) techniques. The presentation unfolds in a systematic, user-friendly style and goes from the basics to cutting-edge research. A complete GPS software receiver implemented using MATLAB code as well as GPS and GIOVE-A signal records allows readers to change various parameters and immediately see their effects. A hands-on method of testing the material covered in the book: supplementary front-end hardware equipment--which may be purchased at http://ccar.colorado.edu/gnss--enables readers working on a Windows or LINUX system to generate real-world data by converting analog signals to digital signals.

The book is aimed at applied mathematicians, electrical engineers, geodesists, and graduate students. It may be used as a textbook in various GPS technology and signal processing courses, or as a self-study reference for anyone working with satellite navigation receivers.

Preface	p. ix
List of Figures	p. xiii
List of Tables	p. xvii
Abbreviations	p. xix
1 Signals and Systems	p. 1
1.1 Characterization of Signals	p. 1
1.1.1 Continuous-Time Deterministic Signals	p. 2
1.1.2 Discrete-Time Deterministic Signals	p. 3
1.1.3 Unit Impulse	p. 3
1.1.4 Rectangular Pulse	p. 4
1.1.5 Random Signals	p. 6
1.1.6 Random Sequence of Pulses	p. 7
1.2 Sampling	p. 8
1.3 Characterization of Systems	p. 9
1.4 Linear Time-Invariant Systems	p. 12
1.5 Representation of Bandpass Signals	p. 14
2 GPS Signal	p. 17
2.1 Signals and Data	p. 17
2.2 GPS Signal Scheme	p. 18
2.3 C/ACode	p. 20
2.3.1 Gold Sequence	p. 20
2.3.2 Gold Sequence Generation-Overview	p. 21
2.3.3 Gold Sequence Generation-Details	p. 22
2.3.4 Correlation Properties	p. 25
2.4 Doppler Frequency Shift	p. 26
2.5 Code Tracking	p. 27
2.6 Navigation Data	p. 28
2.6.1 Telemetry and Handover Words	p. 29
2.6.2 Data in Navigation Message	p. 30
3 Galileo Signal	p. 31
3.1 Signal Theoretical Considerations	p. 31
3.2 Galileo L1 OS Signal	p. 33
3.2.1 Signal Generation	p. 34
3.2.2 Coherent Adaptive Subcarrier Modulation	p. 35
3.2.3 Binary Offset Carrier Modulation	p. 37
3.3 Message Structure	p. 42
3.3.1 Frames and Pages	p. 42
3.3.2 Cyclic Redundancy Check	p. 42
3.3.3 Forward Error Correction and Block Interleaving	p. 43
3.4 Message Contents	p. 45
3.4.1 Time and Clock Correction Parameters	p. 46
3.4.2 Conversion of GST to UTC and GPST	p. 48
3.4.3 Service Parameters	p. 49
3.5 The Received L1 OS Signal	p. 50
4 GNSS Antennas and Front Ends	p. 53
4.1 Background	p. 53
4.2 GNSS L1 Front-End Components	p. 55
4.2.1 GNSS Antenna	p. 55
4.2.2 Filter	p. 57
4.2.3 Amplifier	p. 59
4.2.4 Mixer/Local Oscillator	p. 59
4.2.5 Analog-to-Digital Converter	p. 61
4.3 Resulting Sampled Data	p. 64
4.4 GNSS Front-End ASIC	p. 66
5 GNSS Receiver Operation Overview	p. 69
5.1 Receiver Channels	p. 69
5.1.1 Acquisition	p. 70
5.1.2 Tracking	p. 71
5.1.3 Navigation Data Extraction	p. 72
5.2 Computation of Position	p. 73
6 Acquisition	p. 75
6.1 Motivation	p. 75
6.2 Serial Search Acquisition	p. 76
6.2.1 PRN Sequence Generation	p. 77
6.2.2 Carrier Generation	p. 77
6.2.3 Integration and Squaring	p. 78
6.3 Parallel Frequency Space Search Acquisition	p. 78
6.4 Parallel Code Phase Search Acquisition	p. 81
6.5 Data Size	p. 84
6.6 Execution Time	p. 85
6.7 Parameter Estimation	p. 86
7 Carrier and Code Tracking	p. 87
7.1 Motivation	p. 87
7.2 Demodulation	p. 87
7.3 Second-Order PLL	p. 89
7.3.1 Damping Ratio	p. 92
7.3.2 Noise Bandwidth	p. 92
7.4 Carrier Tracking	p. 93
7.5 Code Tracking	p. 96
7.6 Multipath	p. 101
7.7 Complete Tracking Block	p. 106
7.8 Pseudorange Computations	p. 107
8 Data Processing for Positioning	p. 109
8.1 Navigation Data Recovery	p. 109
8.1.1 Finding the Bit Transition Time and the Bit Values	p. 109
8.2 Navigation Data Decoding	p. 110
8.2.1 Location of Preamble	p. 110
8.2.2 Extracting the Navigation Data	p. 111
8.3 Computation of Satellite Position	p. 114
8.4 Pseudorange Estimation	p. 119
8.4.1 The Initial Set of Pseudoranges	p. 119
8.4.2 Estimation of Subsequent Pseudoranges	p. 120
8.5 Computation of Receiver Position	p. 121
8.5.1 Time	p. 121
8.5.2 Linearization of the Observation Equation	p. 122
8.5.3 Using the Least-Squares Method	p. 123
8.5.4 Real-Time Positioning Accuracy	p. 125
8.6 Time Systems Relevant for GPS	p. 125
8.7 Coordinate Transformations	p. 127
8.8 Universal Transverse Mercator Mapping	p. 129
8.9 Dilution of Precision	p. 130
8.10 World Geodetic System 1984	p. 133
8.11 Time and Coordinate Reference Frames for GPS and Galileo	p. 134
Problems	p. 137
A MATLAB Code	p. 143
A.1 Structure of the Code	p. 143
A.2 The settings Structure	p. 144
A.3 Acquisition Function	p. 145
A.4 Tracking Function	p. 147
A.5 Function postNavigation	p. 148
A.5.1 Pseudorange Computation	p. 149
A.5.2 Position Computation	p. 150
B GNSS Signal Simulation	p. 153
B.1 GPS Signal Simulation	p. 153
B.2 Simulink Implementation	p. 154
B.2.1 C/A Code Generation	p. 155
B.2.2 Navigation Data Generation	p. 157
B.2.3 P Code Generation	p. 158
B.2.4 Combining the Signal Components	p. 158
B.2.5 Upper-Level Implementation	p. 158
B.3 Galileo Signal Generator	p. 159
B.4 Differences in Processing GPS and Galileo Signals	p. 161
B.4.1 Signal Differences	p. 162
B.5 Differences in Signal Processing	p. 164
Bibliography	p. 167
Index	p. 171

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