Distributed Wi-Fi Channel Coordination for DFS Interference Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing Wi-Fi networks face challenges in managing interference and optimizing channel usage in distributed systems, particularly in DFS channels, due to limitations in radar detection and avoidance mechanisms, leading to inefficiencies and disruptions.
Innovation Solution
A distributed Wi-Fi system with cloud-based control that employs multiple access points and collaborative DFS techniques, allowing centralized optimization and coordinated channel selection to minimize interference and ensure robust connectivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If DFS is mandated in the 5GHz band for radar avoidance, then reliability is improved by avoiding radar interference, but productivity deteriorates due to limited frequency channels and additional restrictions
Solution Approach 1:
The patent combines radar detection and channel selection functions into a centralized cloud-based controller that manages multiple access points. This consolidation allows for more efficient utilization of DFS channels across the network while maintaining radar avoidance requirements, thereby improving channel availability without sacrificing reliability.
Solution Approach 2:
The system dynamically selects and switches between DFS and non-DFS channels based on real-time radar detection results and network conditions. This dynamic adaptation allows the network to maximize channel availability by utilizing DFS channels when safe and falling back to non-DFS channels when necessary, resolving the contradiction between reliability and productivity.
2Reliability
If APs perform Channel Availability Check before transmitting on DFS channels, then reliability is improved by ensuring safe channel usage, but time is lost during the checking process
Solution Approach 1:
The cloud-based controller performs preliminary radar detection and channel availability assessment before directing access points to use specific DFS channels. By conducting these checks in advance and maintaining an updated database of safe channels, the system minimizes the time access points need to spend on individual channel checks while ensuring reliable safe channel selection.
Solution Approach 2:
The patent introduces a cloud-based controller as an intermediary that centralizes the Channel Availability Check function. This mediator performs radar detection and channel assessment on behalf of multiple access points, reducing the overall time required for channel checks across the network while maintaining the reliability of safe channel usage through centralized coordination.
3Area of stationary object
If multiple access points operate on DFS channels, then network coverage is improved, but interference increases without coordinated channel selection
Solution Approach 1:
The cloud-based controller assigns specific DFS channels to different access points based on their local geographic locations and detected interference conditions. Each access point operates on optimized channels tailored to its specific environment, allowing multiple access points to expand network coverage while minimizing mutual interference through location-aware channel allocation.
Solution Approach 2:
The system implements continuous feedback mechanisms where access points report channel conditions and interference levels to the cloud-based controller, which then adjusts channel assignments accordingly. This feedback loop enables the network to maintain expanded coverage while dynamically optimizing channel distribution to minimize interference as conditions change.
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
A Wi-Fi system includes a plurality of access points each configured to operate on a plurality of channels including Dynamic Frequency Selection (DFS) frequency channels and non-DFS frequency channels; and at least one access point of the plurality of access points is connected to a controller, wherein the controller is configured to coordinate usage of the plurality of channels between the plurality of access points including usage of the DFS frequency channels pursuant to predetermined DFS rules. One or more access points of the plurality of access points are configured to perform DFS measurements for a Channel Availability Check (CAC) and the DFS measurements are provided to the controller.