B Do multiple WiFi devices create areas of high EMR?

AI Thread Summary
In typical homes or offices, constructive interference from multiple WiFi devices could theoretically exceed safe power levels for individual devices. However, commercial devices operate at power levels significantly below regulatory limits, making this concern largely unfounded. The oscillators in these devices are not phase locked, resulting in a random interference pattern that averages out rather than creating consistent peaks. Therefore, while the additive effect of multiple devices exists, it does not pose a significant risk. Overall, there is no need for concern regarding WiFi exposure in these environments.
ChrisXenon
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Do they constructively interfere to create local high spots?
I'm thinking in a typical house or office, areas of constructive interference may exist which aggregate the fields of maybe 10 WiFi devices.
Wouldn't this mean the safe power levels stipulated for any single device would be routinely be exceeded? And if so, do we care?
 
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They are not stationary, so interference will never sit still in one spot.

The simpler answer, is don't worry.
 
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ChrisXenon said:
I'm thinking in a typical house or office, areas of constructive interference may exist which aggregate the fields of maybe 10 WiFi devices.
Sure. When modeling the exposure, the safest assumption would be to assume they are additive (always constructively interfering).
Wouldn't this mean the safe power levels stipulated for any single device would be routinely be exceeded? And if so, do we care?
No. Commercal home/office devices don't operate at power levels anywhere close to the limits. They are several orders of magnitude too weak:
https://www.fcc.gov/general/radio-frequency-safety-0
 
anorlunda said:
They are not stationary,
Moreover, the oscillators in all the devices are not phase locked so the resulting phasor addition of a number of sources will only ever give you a random-looking product with an RMS value that's the sum of the source waves; no identifiable peaks and troughs, (un?)fortunately.
 
Excellent - thank you both.
 
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