BLE Broadcast Latency via Periodic Advertising and BIG Aggregation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing Bluetooth Low Energy (BLE) technologies face challenges in achieving sub-1 ms peripheral-to-central latency, especially as the number of connected peripheral devices increases, due to high air-time overhead for central-to-peripheral communication.
Innovation Solution
The use of existing BLE broadcast-based signaling protocols, such as periodic advertising with response (PAwR) and broadcast isochronous group (BIG), to efficiently allocate air-time for frequent, short-duration peripheral-to-central transmissions, thereby reducing latency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of time
If traditional BLE connection-based communication is used, then connection reliability is maintained, but peripheral-to-central latency increases due to high air-time overhead for central-to-peripheral communication
Solution Approach 1:
The patent employs periodic advertising with response (PAwR) where the central device transmits periodic advertising packets at configured intervals, and peripheral devices respond within specified time windows. This periodic action structure enables predictable timing for peripheral-to-central communication while minimizing air-time overhead by avoiding continuous connection maintenance, thereby reducing peripheral-to-central latency without sacrificing connection reliability
Solution Approach 2:
The patent implements preliminary configuration where the central device sets up advertising parameters, response time windows, and transmission schedules before actual data exchange occurs. This preliminary action establishes efficient communication protocols in advance, allowing peripheral devices to transmit data with minimal latency when needed without requiring real-time connection establishment or high air-time overhead
2Adaptability or versatility
If multiple peripheral devices are connected to increase system functionality, then device versatility improves, but air-time availability for low-latency peripheral-to-central transmission decreases
Solution Approach 1:
The patent segments the air-time into distinct periodic advertising intervals and response time windows for each peripheral device. Each peripheral receives dedicated time slots within the periodic cycle, allowing multiple devices to share the air-time efficiently without interfering with each other's low-latency transmission requirements. This segmentation enables multiple peripherals to maintain sub-1ms latency despite shared access to the wireless medium
Solution Approach 2:
The patent implements dynamic adjustment of advertising intervals and response time windows based on the number and needs of connected peripherals. The system can adapt the periodic advertising schedule to accommodate varying numbers of devices while maintaining low-latency performance for each active peripheral, thereby supporting system versatility without sacrificing transmission speed
3Productivity
If broadcast isochronous group (BIG) protocol is used to aggregate peripheral data, then air-time utilization efficiency improves, but protocol complexity increases
Solution Approach 1:
The patent implements broadcast isochronous group (BIG) protocol that aggregates data from multiple peripheral devices into a single coordinated transmission cycle. Instead of each peripheral transmitting separately, the BIG protocol merges their data exchanges into unified periodic advertising intervals and response windows, significantly improving air-time utilization efficiency by reducing redundant transmissions and optimizing the time allocation across all connected devices
Data Source
AI summary
Disclosed are techniques to use existing BLE broadcast-based signaling protocols to achieve sub-1 ms peripheral-to-central latency even when multiple peripheral devices share the air-time. The techniques adapt existing BLE advertising or broadcast signaling protocols to efficiently allocate air-time to support frequent peripheral-to-central transmissions that are relatively short in duration and less frequent central-to-peripheral transmissions. A broadcast isochronous group (BIG) protocol may be used to reduce peripheral-to-central latency by aggregating broadcast isochronous streams (BIS) from peripheral devices into a BIG. A one-to-many broadcast event that may carry other broadcast data from the central device to the peripheral devices may be used for time synchronization by the peripheral devices and to configure time parameters of broadcast from the peripheral devices. A reverse many-to-one broadcast from the peripheral devices to the central device may be based on the time parameters. The techniques yield low peripheral-to-central latency and natively support encryption in a BLE controller.