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A comment on A deep dive into why Wi-Fi kind of sucks. Parent comment

Re:A deep dive into why Wi-Fi kind of sucks by JoshTriplett on Saturday March 04, 2017 @12:52PM (#13791988)
> If the client is moving >10MPH relative to a fixed AP (i.e. you're driving past the AP in your car), Wi-Fi doesn't handle that well. Your movement creates Doppler shift in your RF signal, which Wi-Fi can't adjust for (vs. e.g. LTE which does).

Perhaps current-generation WiFi has more of an issue with that, but I've helped build systems that used a much older generation of WiFi in an ad-hoc (no AP) mode between nodes with a speed differential of Mach 1 (between a rocket and the ground). It worked fine, and lost almost no packets over the course of the flight.

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Re:A deep dive into why Wi-Fi kind of sucks by gcr on Saturday March 04, 2017 @01:55PM (#13792290)
Goodness gracious. What was the range of your network? Trying that on a consumer AP would instantly lose the signal, I'd imagine
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Re:A deep dive into why Wi-Fi kind of sucks by JoshTriplett on Saturday March 04, 2017 @02:02PM (#13792319)
Miles, easily. But we had three major advantages:

1) We had a shoulder-mounted directional antenna pointed at the rocket.

2) The rocket had a cylindrical patch antenna wrapped around it.

3) Wifi channel 1 is in an amateur radio band, which means we can amplify it beyond the normal limits. We ran it at 1W.

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Re:A deep dive into why Wi-Fi kind of sucks by joecool1029 on Saturday March 04, 2017 @02:33PM (#13792516)
Eh, I run 1W EIRP on consumer equipment and it's legal[1]. Assuming you are in US? Or not?

[1]: https://www.air802.com/fcc-rules-and-regulations.html

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Re:A deep dive into why Wi-Fi kind of sucks by JoshTriplett on Saturday March 04, 2017 @02:44PM (#13792567)
US, but TTBOMK it wouldn't have been with the combination of amp and antenna. At the time, we'd looked it up and the legal limit without an amateur license was somewhere in the hundreds-of-milliwatts range.
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Re:A deep dive into why Wi-Fi kind of sucks by lend000 on Saturday March 04, 2017 @02:20PM (#13792430)
Normal Wifi is extremely low power by regulation -- the medium itself is capable of much more, and I assume this project used different antennas than you find in your router.
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