Digital Communication Systems Engineering with

Transcription

1 Digital Communication Systems Engineering with Software-Defined Radio Di Pu Alexander M. Wyglinski ARTECH HOUSE BOSTON LONDON artechhouse.com

2 Contents Preface xiii What Is an SDR? Historical Perspective Microelectronics Evolution and its Impact on Communications Technology SDR Definition Anatomy of an SDR Design Considerations Build it and they Will Come Hardware Platforms SDR Software Architecture Chapter Summary Additional Readings 13 References 13 Signals and Systems Overview Signals and Systems Introduction to Signals Introduction to Systems Fourier Transform Introduction and Historical Perspective Definition Properties Sampling Theory Uniform Sampling Frequency Domain Representation of Uniform Sampling Nyquist Sampling Theorem Sampling Rate Conversion Pulse Shaping Eye Diagrams Nyquist Pulse Shaping Theory Two Nyquist Pulses Filtering Ideal Filter vii

3 viii Contents Z-Transform Digital Filtering Chapter Summary Problems 47 References 50 Probability Review Fundamental Concepts Set Theory Partitions Functions Axioms and Properties of Probability Conditional Probability Law of Total Probability and Bayes' Rule Independence Random Variables Discrete Random Variables Continuous Random Variables Cumulative Distribution Functions Central Limit Theorem The Bivariate Normal Random Processes Statistical Characteristics of Random Processes Stationarity Gaussian Processes Power Spectral Density and LTI Systems Chapter Summary Additional Readings Problems 80 References 88 Digital Transmission Fundamentals What is Digital Transmission? Source Encoding Channel Encoding Digital Modulation Power Efficiency Pulse Amplitude Modulation Quadrature Amplitude Modulation Phase Shift Keying Power Efficiency Summary Probability of Bit Error Error Bounding 107

4 Contents ix 4.4 Signal Space Concept Gram-Schmidt Orthogonalization Optimal Detection Signal Vector Framework Decision Rules Maximum Likelihood Detection in an AWGN Channel Basic Receiver Realizations Matched Filter Realization Correlator Realization Chapter Summary Additional Readings Problems 125 References 130 Basic SDR Implementation of a Transmitter and a Receiver Software Implementation Repetition Coding Interleaving BER Calculator Receiver Implementation over an Ideal Channel USRP Hardware Implementation Frequency Offset Compensation Finding Wireless Signals: Observing IEEE WiFi Networks USRP In-phase/Quadrature Representation Open-Ended Design Project: Automatic Frequency Offset Compensator Introduction Objective Theoretical Background Chapter Summary Problems 149 References 152 CHAPTER 6 Receiver Structure and Waveform Synthesis of a Transmitter and a Receiver 6.1 Software Implementation Observation Vector Construction Maximum-Likelihood Decoder Implementation Correlator Realization of a Receiver in Simulink 6.2 USRP Hardware Implementation Differential Binary Phase-Shift Keying Differential Quadrature Phase-Shift Keying Accelerate the Simulink Model that Uses USRP Blocks 6.3 Open-Ended Design Project: Frame Synchronization Frame Synchronization

5 X Contents Barker Code Simulink Models Hints for Implementation Hints for Debugging Chapter Summary Problems 173 Reference 175 Multicarrier Modulation and Duplex Communications Theoretical Preparation Single Carrier Transmission Multicarrier Transmission Dispersive Channel Environment OFDM with Cyclic Prefix Frequency Domain Equalization Bit and Power Allocation Software Implementation MATLAB Design of Multicarrier Transmission Simulink Design of OFDM USRP Hardware Implementation Eye Diagram Matched Filter Observation Open-Ended Design Project: Duplex Communication Duplex Communication Half-Duplex Time-Division Duplexing Useful Suggestions Evaluation and Expected Outcomes Chapter Summary Problems 201 References 204 Spectrum Sensing Techniques Theoretical Preparation Power Spectral Density Practical Issues of Collecting Spectral Data Hypothesis Testing Spectral Detectors and Classifiers Software Implementation Constructing Energy Detector Observing Cyclostationary Detector USRP Hardware Experimentation Open-Ended Design Project: CSMA/CA Carrier Sense Multiple Access 230

6 Contents xi Collision Avoidance Implementation Approach Useful Suggestions Evaluation and Expected Outcomes Chapter Summary Problems 234 References 236 Applications of Software-Defined Radio Cognitive Radio and Intelligent Wireless Adaptation Wireless Device Parameters Vehicular Communication Networks VDSA Overview Transmitter Design Receiver Design VDSA Test-Bed Implementation Satellite Communications Chapter Summary 250 References 250 Getting Started with MATLAB and Simulink 253 A.l MATLAB Introduction 253 A.2 Edit and Run a Program in MATLAB 253 A.3 Useful MATLAB Tools 254 A.3.1 Code Analysis and M-Lint Messages 254 A.3.2 Debugger 255 A.3.3 Profiler 256 A.4 Simulink Introduction 257 A. 5 Getting Started in Simulink 257 A.5.1 Start a Simulink Session 257 A.5.2 Start a Simulink Model 257 A.5.3 Simulink Model Settings 258 A.6 Build a Simulink Model 259 A.6.1 Obtain the Blocks 260 A.6.2 Set the Parameters 260 A.6.3 Connect the Blocks 262 A. 7 Run Simulink Simulations 264 References 266 Universal Hardware Driver (UHD) 267 B. l Setting Up Your Hardware 267 B.2 Installing UHD-Based USRP I/O Blocks 267 B.3 Burning the Firmware to an SD Card 268

7 xii Contents B.4 Configure the Ethernet Card 268 B.5 Modify the Iptables 269 B.6 Each Time You Use 269 B.7 Problems with Unicode 269 References 270 Data Flow on USRP 271 C. l Receive Path 271 C.l.l Situation C. l.2 Situation C.2 Transmit Path 274 References 276 Quick Reference Sheet 277 D. l LINUX 277 D. l.l Helpful Commands 277 D.l.2 Modify the Iptables 277 D.2 MATLAB 278 D.2.1 How to Start MATLAB 278 D.2.2 The MATLAB Environment 278 D.2.3 Obtaining Help 278 D.2.4 Variables in MATLAB 278 D.2.5 Vectors and Matrices in MATLAB 279 D.3 USRP2 Hardware 279 D.3.1 XCVR2450 Daughtercard 279 D.3.2 Sampling 280 D.3.3 Clocking 281 D.3.4 DDCandDUC 281 D.4 Differential Phase-Shift Keying (DPSK) 282 Reference 282 Trigonometric Identities 283 About the Author 285 Index 287