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I lose wifi signal consistently in my bedroom on my 80Mhz wide 5Ghz wifi.

I just now reduced it to 20Mhz, and though there is a (slight) perceptible drop in latency, those 5 extra dB I gained from Signal/Noise have given me wifi in the bedroom again

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Every doubling of the channel width costs roughly 3dB. Shannon's law strikes again!

Every doubling of the channel width doubles the Shannon limit*

* An a gaussian white noise environment, which WiFi usually isn't in.

*If the bandwidth of the Analog Front End (AFE) and Analog to Digital Converter (ADC) / Digital to Analog Converter (DAC) doubles as well. In the real world the AFE of any wifi radio has a fixed bandwidth, with the ADC sampling rate and accuracy being fixed as well. The end result is that doubling the channel width in a wireless network requires a received signal strength that is roughly 3 dB more in real world devices. This constraint is quite visible in data sheets for most wifi cards like here: https://compex.com.sg/wp-content/uploads/2024/01/wle7002e25-...

Wow! There are certain areas of my house that I get such bad wifi signal that I often switch to cellular data since it's more reliable. I didn't even know you could change a setting like this to reduce speeds but improve reliability - it worked like a charm, thanks!

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