Wi-Fi Signal Levels
If you want to improve your Wi-Fi network, Ars Technica has two very good articles on Wi-Fi signal—theory and practice.
In summary:
- Application latency is more important than network speed.
- The worst ping times affect performance, not the best ping times.
- Multiple devices on the network will interfer with each other.
- Any radio signal on the same frequency (not just Wi-Fi signals) at a level of -62dBm or stronger stops communications.
- Any Wi-Fi signals (from your network or your neighbours) at a level of -82dBm or stronger stops communications.
So simple network speed testing is not a good indicator of how good the network will perform, since they are usually done when other devices are not heavily using the network. They indicate the best performance the network is capable of, but it is the worst performance that matters.
Since all Wi-Fi devices share the radio spectrum, it is the available air-time that matters. Therefore, it is more important to:
- Use wired network connections when possible, to free up air-time for the devices using Wi-Fi.
- Ensure all Wi-Fi devices have equally good reception, otherwise the worst device will bring down the performance for all the other devices.
- Be satisfied with a signal level of about -67dBm. Getting a strong signal than that won’t make much difference.
For more details, read the articles.