There is a growing need for books and preparatory materials that can help wireless engineers prepare for the IEEE WCET (Wireless Communications Engineering Technologies) certification exam. This book offers a broad exposure to the wireless communications field as it is practiced in the real world, providing the necessary practical, hands-on knowledge. The author, who was involved with the certification program development, shares in-depth knowledge and insight on the WCET exam. Readers planning to take the exam, engineers seeking to increase their knowledge of WCET, and graduate students and professors in wireless communications will find this guide invaluable.

K. Daniel Wong, Phd (Stanford), is a member of the Practice Analysis Task Force (PATF), which was organized by the IEEE Communications Society and created the initial list of topics for the WCET. After teaching at the Malaysia University of Science and Technology, he started his own training and consulting company in wireless networking and software. He often teaches a variety of highly rated and well received courses on wireless communications. In addition, he has contributed to numerous books, journal and magazine papers, and conference papers.

FOREWORD xix

PREFACE xxi

I PRELIMINARIES

1 Introduction 3

1.1 Notation 4

1.2 Foundations 4

1.3 Signals and Systems 12

1.4 Signaling in Communications Systems 27

II RADIO FREQUENCY, ANTENNAS, AND PROPAGATION

2 Introduction to Radio Frequency, Antennas, and Propagation 37

2.1 Mathematical Preliminaries 37

2.2 Electrostatics, Current, and Magnetostatics 41

2.3 Time-Varying Situations, Electromagnetic Waves, and Transmission Lines 46

2.4 Impedance 56

2.5 Tests and Measurements 57

3 Radio-Frequency Engineering 63

3.1 Introduction and Preliminaries 64

3.2 Noise 70

3.3 System Issues Related to Nonlinearity 80

3.4 Mixing and Related Issues 85

3.5 Oscillators and Related Issues 87

3.6 Amplifiers and Related Issues 89

3.7 Other Components 90

4 Antennas 93

4.1 Characterization 94

4.2 Examples 105

4.3 Antenna Arrays 111

4.4 Practical Issues: Connecting to Antennas, Tuning, and so on 122

5 Propagation 125

5.1 Electromagnetic Wave Propagation: Common Effects 126

5.2 Large-Scale Effects in Cellular Environments 132

5.3 Small-Scale Effects in Cellular Environments 137

5.4 Incorporating Fading Effects in the Link Budget 148

III WIRELESS ACCESS TECHNOLOGIES

6 Introduction to Wireless Access Technologies 159

6.1 Review of Digital Signal Processing 160

6.2 Digital Communications for Wireless Access Systems 169

6.3 The Cellular Concept 173

6.4 Spread Spectrum 177

6.5 OFDM 185

7 Component Technologies 193

7.1 Medium Access Control 193

7.2 Handoff 202

7.3 Power Control 208

7.4 Error Correction Codes 210

8 Examples of Air-Interface Standards: GSM, IS-95, WiFi 219

8.1 GSM 220

8.2 IS-95 CDMA 226

8.3 IEEE 802.11 WiFi 235

9 Recent Trends and Developments 249

9.1 Third-Generation CDMA-Based Systems 249

9.2 Emerging Technologies for Wireless Access 253

9.3 HSPA and HRPD 258

9.4 IEEE 802.16 WiMAX 262

9.5 LTE 270

9.6 What's Next? 273

IV NETWORK AND SERVICE ARCHITECTURES

10 Introduction to Network and Service Architectures 277

10.1 Review of Fundamental Networking Concepts 278

10.2 Architectures 285

10.3 IP Networking 290

10.4 Teletraffic Analysis 301

11 GSM and IP: Ingredients of Convergence 307

11.1 GSM 308

11.2 VoIP 315

11.3 QoS 323

12 Toward an All-IP Core Network 333

12.1 Making IP Work with Wireless 333

12.2 GPRS 341

12.3 Evolution from GSM to UMTS up to the Introduction of IMS 346

12.4 IP Multimedia Subsystem 354

12.5 Other Networks 362

13 Service Architectures, Alternative Architectures, and Looking Ahead 367

13.1 Services 367

13.2 Service Architectures 371

13.3 Mobile Ad Hoc Networks 379

13.4 Mesh, Sensor, and Vehicular Networks 384

V MISCELLANEOUS TOPICS

14 Network Management 393

14.1 Requirements and Concepts 393

14.2 Network Management Models 394

14.3 SNMP 397

15 Security 415

15.1 Basic Concepts 415

15.2 Cryptography 419

15.3 Network Security Protocols 422

15.4 Wireless Security 432

16 Facilities Infrastructure 443

16.1 Communications Towers 444

16.3 Additional Topics 462

17 Agreements, Standards, Policies, and Regulations 467

17.1 Agreements 468

17.2 Standards 469

17.3 Policies 478

17.4 Regulations 479

EXERCISE SOLUTIONS 487

APPENDIX A: SOME FORMULAS AND IDENTITIES 497

APPENDIX B: WCET GLOSSARY EQUATION INDEX 499

APPENDIX C: WCET EXAM TIPS 501

APPENDIX D: SYMBOLS 503

APPENDIX E: ACRONYMS 509

INDEX 519