Re:New Chip Brings Ultra-Low Power Wi-Fi Connectivity to IoT...
by aneutron on Wednesday February 26, 2020 @06:27PM
(#22428633)
"Knows nothing beyond what a patch antenna is" here, and I have a couple of question if you could please answer them:
- Doesn't this degrade the quality of the original signal ? (i.e. some sort of destructive interference)
- Isn't it illegal to interfere in signals this way ?
Re:New Chip Brings Ultra-Low Power Wi-Fi Connectivity to IoT...
by ac29 on Wednesday February 26, 2020 @08:25PM
(#22429458)
If this is reflecting onto a different channel (frequency) then it shouldnt interfere with the original signal (except perhaps by reducing its effective power output by a small amount).
It is a general FCC rule that radios and certain other types of devices are not supposed to intentionally cause interference, but in this case there shouldn't be any. Even if there was same channel interference, its not necessarily considered intentionally harmful - for example, its not illegal to use the same WiFi channel as your neighbor as long as you are within other specified technical limits such as transmit power or antenna gain. But doing so for the express purpose of interfering with them would be.
> The Wi-Fi radio runs on extremely low power by transmitting data via a technique called backscattering. It takes incoming Wi-Fi signals from a nearby device (like a smartphone) or Wi-Fi access point, modifies the signals and encodes its own data onto them, and then reflects the new signals onto a different Wi-Fi channel to another device or access point.