WIFI EVOLUTION | MICHAIL BALKONIS WIFI EVOLUTION “BEYOND WIFI 6” Master's thesis Digital Communications & Networks Balkonis Michail mwe1905 Supervisor: Angeliki Alexiou Athens, June 2021 pg. 1 WIFI EVOLUTION | MICHAIL BALKONIS This thesis is dedicated to my beloved sister Elli as well as my parents who gave us all the supplies… pg. 2 WIFI EVOLUTION | MICHAIL BALKONIS TABLE OF CONTENTS TABLE OF CONTENTS ........................................................................................................................................... 3 List of Abbreviations ........................................................................................................................................... 6 Acknowledgements............................................................................................................................................. 8 ABSTRACT ........................................................................................................................................................... 9 ΠΕΡΙΛΗΨΗ ........................................................................................................................................................ 10 1. INTRODUCTION IN WIRELESS TECHNOLOGY ............................................................................................. 11 1.1 Brief History of Wireless Technology ................................................................................................. 13 1.2 IEEE 802.11 Architecture .................................................................................................................... 13 1.2.1 Station ....................................................................................................................................... 13 1.2.2 Access Point ............................................................................................................................... 13 1.2.3 Wireless Medium ....................................................................................................................... 14 1.3 Architectures ..................................................................................................................................... 14 1.4 Evolution of the standard 802.11 ....................................................................................................... 16 1.5 IEEE 802.11 Physical Layer ................................................................................................................. 21 1.5.1 Physical layer (phy) frame structure .......................................................................................... 22 1.5.2 Operating Physical Layer ............................................................................................................ 23 1.6 Medium Access Control (MAC) Layer & Key Technologies ................................................................. 24 1.6.1 Distributed Coordination Function (DCF) ................................................................................... 24 2. INTRODUCTION OF WI FI 6 (802.11AX) ...................................................................................................... 26 2.1 Can 802.11ax go so fast? .................................................................................................................... 27 2.2 Design Goals of Wi-Fi 6 ...................................................................................................................... 28 2.3 New Features in Wi-Fi 6 ..................................................................................................................... 29 2.4 Overview of Wi-Fi 6 ........................................................................................................................... 30 2.5 Physical Enhancements Overview of 802.11ax .................................................................................. 32 2.5.1 New modulation technology ...................................................................................................... 33 2.5.2 New Coding Strategy .................................................................................................................. 36 2.5.3 New Mechanism Subcarrier Division .......................................................................................... 36 2.5.4 Enhanced Multiple Access Technology ....................................................................................... 37 2.5.5 Channel Bonding Enhancement ................................................................................................. 44 2.5.6 New Headers PPDU .................................................................................................................... 47 pg. 3 WIFI EVOLUTION | MICHAIL BALKONIS 2.6 BSS Coloring ....................................................................................................................................... 49 2.6.1 What is BSS Coloring? ................................................................................................................ 50 2.6.2 BSS coloring (Benefits and Advantages) ..................................................................................... 50 2.7 Target Wake Time .............................................................................................................................. 51 2.8 Use Cases for Wi-Fi 6 Technology ...................................................................................................... 52 2.9 User Experience of Wi-Fi 6 ................................................................................................................. 53 2.10 Advantages in Wi-Fi 6 ........................................................................................................................ 53 2.11 Disadvantages in Wi-Fi 6 .................................................................................................................... 54 3. THE FUTURE OF WI-FI ................................................................................................................................ 55 3.1 Wi-Fi 6E: “The New Lane” .................................................................................................................. 55 3.2 The Importance of 6GHz .................................................................................................................... 55 3.3 IEEE 802.11ax/be Frequency Bands ................................................................................................... 56 3.4 Benefits of 6 GHz ............................................................................................................................... 56 3.5 6 GHz Wi-Fi Challenges and Strategics ............................................................................................... 57 4. 802.11BE WI-FI 7: EXTREMELY HIGH THROUGHPUT ................................................................................. 58 4.1 Evolution to Wi-Fi 7 .......................................................................................................................... 58 4.2 How Extreme High Throughput can be achieved ? ............................................................................. 59 4.3 The Development Timeline of IEEE 802.11be ..................................................................................... 60 4.3.1 Release 1 Features ..................................................................................................................... 61 4.3.2 Release 2 Features ..................................................................................................................... 63 4.4 Physical Frame ................................................................................................................................... 65 4.5 The MAC Layer ................................................................................................................................... 68 4.5.1 Multi-link operation ................................................................................................................... 68 4.5.2 enhancements of Spatial streams and MIMO ............................................................................ 74 4.5.3 Multi-Ap Features ...................................................................................................................... 75 4.5.4 HARQ ......................................................................................................................................... 78 4.5.5 Non-Orthogonal Multiple Access ............................................................................................... 80 4.5.6 The Channel Sounding................................................................................................................ 81 4.6 Physical Enhancements for EHT ......................................................................................................... 83 4.6.1 New Bandwidth Mode ............................................................................................................... 85 4.6.2 Support Multi RU ....................................................................................................................... 87 4.6.3 Preamble Design of Extremely High Throughput........................................................................ 88 4.6.4 Higher-Order Modulation.......................................................................................................... 90 pg. 4 WIFI EVOLUTION | MICHAIL BALKONIS 4.7