Channel Allocation for Wi-Fi 6

Today it is common that when a customer pays for a 100 Mbit/s Internet back-haul line from his Internet Service Provider (ISP), he obtains only 10 Mbit/s when using his Wi-Fi 5 network. This due to interference from his neighbor’s network. This is a huge problem because the primary medium for global Internet traffic is Wi-Fi since it carry around half the Internet traffic.  Wi-Fi 6 handles interference more efficiently through a new channel-sharing capability compared to earlier standards. It will constitute 27.4 % total Wi-Fi traffic in 2023, increasing fast. Rapid deployment of Wi-Fi 6 is therefore an important national effort to preserve Norwegian competitiveness.  

The Wi-Fi project 6

Our solution will not rely on remote collection of metadata sent from the users over non-encrypted lines to cloud servers abroad, in conflict with the General Data Protection Regulations (GDPR), such as in existing solutions. A cluster is typically an apartment building with users that disturb each other. All these users generates shared neighborhood reports, resulting in autonomous clusters where channels assigned in a completely decentralized fashion. Since the cluster size is limited and independent of the number of networks to be coordinated, our system will be scalable. Our project will enable Access Points (APs) to work in a completely autonomous peer to peer manner, making our system scalable and being able to operate without the need of any additional infrastructure and without the assistance of an Internet Service Provider, still achieving the performance of managed enterprise networks. We have already implemented and tested our ideas using WI-Fi 5. Now we will test it in a Wi-Fi 6 network, which can offer higher bit-rates since the channel access scheme uses OFDMA and can remove interference from neighbors if implemented correctly. This will be a significant breakthrough.

Graphs

The problem of channel allocation can be formulated as a graph coloring problem. In Wi-Fi 5, an AP is represented by a vertex which shall be assigned a given color (channel), while the edges represent disturbances between the APs.  

In Wi-Fi 6, a vertex represents each client and the edges represent disturbances between clients and APs. The Vertex Coloring approach} is a well-known, but time-consuming solution to implement. The same channel cannot be assigned to two different vertices if there is an edge with a significant weight connecting them, where this weight is estimated based on the level of interference etc. Those nodes that do not use our algorithms and software are called rogues, therefore, they are vertices with fixed colors. The performance increases gracefully when the number of rouges is reduced.

The Master thesis

In Wi-Fi 6 the graph coloring task is very time consuming. There are however, tricks which makes it possible to implement this in an AP. The task is to perform simulations on how to do channel allocation for Wi-Fi 6. There will be a panel of experts from the Empathic Radio project, following, advising and supporting the Master candidate.  

Publisert 10. nov. 2021 00:00 - Sist endret 10. nov. 2021 15:23

Omfang (studiepoeng)

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