BLE CIG Synchronization for Multi-Channel Audio
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Bluetooth Low Energy (BLE) systems face issues with synchronization of multiple audio channels, leading to audio lacking due to data loss or corruption during transmission, particularly in systems compliant with Revision v5.2 of the Bluetooth Core Specification, which results in degraded audio quality and increased transmission collisions.
Innovation Solution
The implementation of dynamically sized buffering and the use of Connected Isochronous Groups (CIGs) to facilitate synchronization, where CIG reference-point and synchronization-point parameters are established relative to the ISO interval signal, allowing for synchronized transmission of Protocol Data Units (PDUs) across multiple BLE-compliant slave devices, thereby improving audio transmission and synchronization.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If re-transmission is performed for lost or corrupted data packets in BLE systems, then data completeness is improved, but transmission synchronization deteriorates causing audio lacking
Solution Approach 1:
The system performs preliminary actions by pre-scheduling re-transmission opportunities within the same ISO event and preparing re-transmission buffers in advance. When data loss is detected, the system can immediately utilize these pre-prepared resources to re-transmit packets without causing synchronization disruption to other audio channels.
2Quantity of substance
If multiple BLE-compliant links are used to increase bandwidth, then data transmission capacity is improved, but synchronization complexity increases
Solution Approach 1:
The system merges multiple BLE-compliant links into a unified transmission framework by establishing a common reference-point parameter and synchronization-point parameter relative to a shared ISO interval signal. This allows independent multiple links to be coordinated through centralized timing parameters, reducing synchronization complexity while maintaining increased bandwidth capacity.
3Productivity
If re-transmitted packets stay in the same wireless channel, then transmission efficiency is improved, but data loss frequency increases due to transmission collisions
Solution Approach 1:
The system segments the re-transmission process by dividing it into multiple opportunities within the same ISO event. Instead of a single re-transmission attempt, the system creates multiple segmented transmission opportunities at different time points, allowing packets to be re-transmitted in segments across different channels or time slots, thereby reducing collision probability while maintaining overall transmission efficiency.
Data Source
AI summary
Mechanisms and methods are provided for improving wireless audio transmission and synchronization for multi-channel Bluetooth® Low Energy (BLE) systems. In various embodiments, mechanisms and methods may include generating transmissions having a plurality of Protocol Data Units (PDUs) to BLE-compliant slave devices. The plurality of PDUs may be stored in a buffer. When an error is determined to have occurred in transmitting one of the PDUs, a re-transmission to the slave device may be generated, which may include the PDU in error and any subsequent PDUs of the plurality of PDUs.