Unraveling Bluetooth LE Audio: Stretching the Limits of Interoperable Wireless Audio with Bluetooth Next-Generation Low Energy Audio Standards

Description

Explore how Bluetooth Low Energy (LE) has transformed the audio landscape, from music streaming to voice recognition applications. This book describes the rationale behind moving to LE audio, the potential power savings, and how various specifications need to be linked together to develop a final end product.  LE Audio is a natural development of the Bluetooth audio standard. The standard is spread across more than a dozen different specifications, from application profiles, down to the core transports in both Host part and Controller part. You'll see how this new architecture of the Bluetooth audio stack defines a LE Audio stack from the Core Controller to the Host Protocols, and Profiles. You’ll also learn how to free yourself from wires and charging. LE Audio introduces a new audio compression codec called LC3 (Low Complexity Communication Codec), which covers sampling rates for the full range of voice and media application at high fidelity, low complexity and low bit-rate and is ideal for new applications – such as voice assistance and gaming. Unraveling Bluetooth Low Energy Audio provides full context to anyone who is curious to learn about the new LE Audio technology. What You'll LearnUnderstand the advantages of LE audio over current standardsDescribe the overall Bluetooth LE audio stack and its various blocksEnable LE audio with the Core Controller specificationSee how an end-to-end application works its through the LE audio ecosystemExamine how LE Audio addresses current and future trends in interoperable wireless audio Who This Book Is For The target audience for this book are developers, manufacturers, students, lecturers, teachers, technology geeks, platform integrators, and entrepreneurs.  Table of Contents About the Authors Preface Acknowledgements Chapter 1: Introduction Motivation for LE Audio LE Audio Architecture App Layer Control Layer Transport Layer Codec Compatibility with Classic Audio Audio Speech Audio Media Audio Hybrid Audio The Social Aspect of Audio Audio and Bluetooth Classic Audio Evolution What About Music? Classic Audio Applications Classic Audio Limits The One Architecture Summary Chapter 2: Bluetooth Overview Bluetooth Radio Model Media Access Control (MAC) Physical Layer Modulation Types Logical Link Control The MAC Scheduler Packet Structure Low Power Modes Host and Controller Bluetooth Low Energy Similarities and Differences to Classic Radio Model Physical Layer Modulation Types Logical Link Control The MAC Scheduler Packet Structure Host and Controller Classic Bluetooth Audio Summary Chapter 3: One Architecture Overview The LE Audio Layers App Layer Control Layer Stream Control Profiles and Services Basic Audio Profile (BAP) Unicast Broadcast Endpoints Published Audio Capabilities Service (PACS) Audio Stream Control Service (ASCS) Broadcast Audio Scan Service (BASS) Capturing and Rendering Profiles and Services Volume Control Microphone Control Content Control Profiles and Services Call Control Media Control Coordination Set Profiles and Services Routing Audio Profiles and Services Common Audio Profile (CAP) Codec Layer Low Complexity Communication Codec (LC3) Audio Latency and Retry Effort Transport Layer Unicast Transport – Connected Isochronous Stream (CIS) Broadcast Transport – Broadcast Isochronous Stream (BIS) Advertising (ADV) Signaling Connection – ACL LE Audio Host and Controller Host EATT Controller Summary Chapter 4: App Layer Architecture LE Audio Application Use Case–Based Profiles Telephony and Media Audio Profile Hearing Aid Profile Public Broadcast TV Profile Multichannel Surround Profile Summary Chapter 5: Control Layer Architecture Audio Stream Discovery and Establishment Unicast Roles Device Discovery Connection Establishment Audio Capability Discovery Audio Stream Establishment Idle ➤ Configured State Transition Configured ➤ Streaming State Transition Streaming ➤ Configured State Transition Idle State Transition Presentation Delay Zero Discovery and Zero Configuration Broadcast Roles Device Discovery Connection Establishment Audio Capability Discovery Audio Stream Establishment Remote Scanning Scan Offloading Using PAST Volume Control Microphone Control Media Control Telephony Control Coordination of Devices Routing Control Common Audio Profile Summary Chapter 6: LC3 Codec Why a New Codec? LC3 Compared with SBC/mSBC Listening Quality Latency and Complexity Bitrate Summary Chapter 7: Transport Layer Isochronous Channels Audio Quality of Service Latency Bitrate Reliability Isochronous Channel Types CIS Logical Transport BIS Logical Transport CIS Control BIS Control Summary Chapter 8: Vision Bring It All Together Future Use Case Examples Museum Home Theater Online Music Jam Interactive Classroom Trade Show Home Recording Studio Online Gaming Epilogue Index