About the Authors xiii
Preface xv
Acknowledgments xvii
1 Introduction 1
1.1 Introduction to Radio Positioning 3
1.2 Short and Medium-range Radiolocation Technologies 5
1.3 Overview of the Book 10
2 Radio Propagation 15
2.1 Statistical Multipath Theory 16
2.2 Radio Propagation Characteristics at Different Distance Scales 29
2.3 Measurements 39
2.4 Excess Delays in Radio Propagation 44
2.5 Antenna Effects 51
3 Signal Detection by Correlation 55
3.1 Transmitter Signal 55
3.2 Receiver Signal Processing 58
4 Bandlimited Time-of-Arrival Measurements 77
4.1 Wideband Multipath Theorem 78
4.2 Bandlimited Correlogram Characteristics 80
4.3 Model of Bandlimited Correlogram 83
4.4 Peak-Tracking Algorithm Performance 86
4.5 Leading-edge Projection Tracking Algorithm 95
4.6 Leading-edge Ratio Algorithm 101
4.7 Multipath Phase 108
4.8 Performance Summary of Tracking Algorithms 110
5 Fundamentals of Positioning Systems 115
5.1 Navigation Systems and Tracking Systems 116
5.2 System Architecture 118
5.3 Overview of Position Determination 132
5.4 Indoor Performance Issues 139
6 Noniterative Position Determination 147
6.1 Basic Positioning Methods 147
6.2 Linearization-Based Least-Squares Methods 157
6.3 Spherical Interpolation Approach 159
6.4 Quasi-Least-Squares Solution 164
6.5 Linear-Correction Least-Squares Approach 168
7 Iterative Position Determination 173
7.1 Iterative Algorithms 173
7.2 Filtering-Based Methods 184
7.3 Data Smoothing 191
8 Positioning Accuracy Evaluation 199
8.1 Accuracy Measures 199
8.2 Cramer--Rao Lower Bound in Line-of-Sight Conditions 201
8.3 Derivation of Cramer--Rao Lower Bound in Non-Line-of-Sight Conditions 207
8.4 Approximate Variance of Linear Least-Squares Algorithm 210
8.5 Accuracy Comparison 215
9 Geometric Dilution of Precision Analysis 223
9.1 Geometric Error Analysis 223
9.2 Statistical Error Analysis 226
9.3 Calculation of Geometric Dilution of Precision 228
9.4 Accuracy Probabilities 230
9.5 Special Cases: Analytical Solutions to Geometric Dilution of Precision 232
9.6 Geometric Dilution of Precision Performance 244
10 Multipath Mitigation 249
10.1 Residual-Weighting-based Method 249
10.2 Filtering-based Method 250
10.3 Constrained Optimization 253
10.4 Scatterer-based Method 266
10.5 Error Statistics 270
10.6 Propagation-Model-based Method 274
10.7 Pattern Matching 276
10.8 Performance Analysis 280
11 Anchor-based Localization for Wireless Sensor Networks 289
11.1 Characteristics of Wireless Sensor Networks 290
11.2 Coarse Localization Methods 291
11.3 Global Localization Methods 294
11.4 Localization with Unknown Internal Delays and Clock Offsets 298
12 Anchor Position Accuracy Enhancement 321
12.1 Impact of Anchor Location Accuracy on Sensor Node Localization 322
12.2 Line-of-Sight and Non-Line-of-Sight Propagation Models 324
12.3 Anchor Position Accuracy Bound 326
12.4 Accuracy Improvement Based on Distance and Angle Estimates 330
12.5 Accuracy Improvement Based on Distance Estimates 335
13 Anchor-Free Localization 343
13.1 Robust Quads 344
13.2 Multidimensional Scaling Method 344
13.3 Mass--Spring Model 348
13.4 Hybrid Approach 349
13.5 Graphical Model 352
13.6 Clustering and Stitching 353
13.7 Referent Coordinate System Establishment 355
13.8 Cramer--Rao Lower Bound 356
13.9 Accuracy of Location Estimates 359
13.10 Distance-Error-based Accuracy Measure 363
13.11 Accuracy Evaluation 364
14 Non-Line-of-Sight Identification 371
14.1 Data Smoothing 372
14.2 Distribution Tests 373
14.3 Calculating Level Crossing Rate and Fade Duration 379
14.4 Estimating the Rician Factor 381
14.5 Generalized Likelihood Ratio Test 381
14.6 Nonparametric Method 383
14.7 Using Intermediate Location Estimation 385
14.8 Neyman--Pearson Test 387
14.9 Joint Time-of-Arrival and Received Signal Strength-based Approaches 390
14.10 Angle-of-Arrival-based Methods 395
Appendix A: Hyperbolic Navigation 409
A.1 Analytical Equations of a Hyperbola 409
A.2 Solution to Hyperbolic Navigation 412
A.3 Solution to Example Problem 414
Appendix B: Radio Propagation Measurement Techniques 417
B.1 Measurements with a Network Analyzer 417
B.2 Time-Domain Measurements 421
Index
