3 ms·
My point was that at the RF level, BT packets get swamped by Wifi (hence only getting through in the gaps). With Wifi putting out 100mw and BT around 1mw, added
by zh3 3y ago
My point was that at the RF level, BT packets get swamped by Wifi (hence only getting through in the gaps). With Wifi putting out 100mw and BT around 1mw, added to WiFi devices generally having much larger antenna, WiFi is the thing to workaround. And in a busy environment (I often see dozen's of APs in a scan) pretty much every channel is occupied - making it challenging to get much data through at BT-type power levels.
- lxgr 3y agoAirPods are Bluetooth Class 1 devices and can transmit at 100 mW as well! A larger (omnidirectional) antenna doesn't increase the EIRP either, which is what is limited in case for both Bluetooth and 802.11. > And in a busy environment (I often see dozen's of APs in a scan) pretty much every channel is occupied Most of these channels are overlapping anyway, so we're really only talking about 3 or so channels in the 2.4 GHz band. And due to CSMA/CA, 802.11 has to back off in case of sensing any sufficiently powerful interference. Bluetooth Class 1 definitely seems like it would qualify, so Bluetooth will actually make 802.11 on all of these channels back off, reducing the duty cycle and creating enough gaps for Bluetooth to statistically get its transmissions through. Bluetooth audio (A2DP) only needs about 300 kbit/s anyway; that's less than 20% of the total possible Bluetooth throughput, so even if every single transmission needs 5 retries, you'd still not have audio dropouts. I've never been in an environment where 802.11 was actually able to overwhelm Bluetooth audio connections, neither A2DP (which is heavily buffered), nor HFP (which isn't). Microwaves or older "non-backoff" 2.4 GHz transmitters (old babyphones, analog cordless phones etc.) definitely can, though.