* Re: [Make-wifi-fast] wifi tv antenna count
2024-02-23 15:53 [Make-wifi-fast] wifi tv antenna count Dave Taht
@ 2024-02-23 18:20 ` Bob McMahon
0 siblings, 0 replies; 2+ messages in thread
From: Bob McMahon @ 2024-02-23 18:20 UTC (permalink / raw)
To: Dave Taht; +Cc: Make-Wifi-fast, discuss
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Paul Baran in 1994
- Shorter range rf transceivers connected to fiber could produce a
significant improvement - - tremendous improvement, really.
- A mixture of terrestrial links plus shorter range radio links has the
effect of increasing by orders and orders of magnitude the amount of
frequency spectrum that can be made available.
- By authorizing high power to support a few users to reach slightly
longer distances we deprive ourselves of the opportunity to serve the many.
- Communications systems can be built with 10dB ratio
- Digital transmission when properly done allows a small signal to noise
ratio to be used successfully to retrieve an error free signal. And, never
forget, any transmission capacity not used is wasted forever, like water
over the dam. Not using such techniques represent lost opportunity.
Some think the AP/STA power imbalance is a good thing, allowing an AP to
reach devices at further distances with a higher MCS. I think it's also a
design flaw similar to bufferbloat. Many times there has to be an RTS/CTS,
shutting down other conversations. so a remote node, typically on a
battery, can "whisper" a signal to the AP. Not good.
FiWi, with power symmetry, can fix this (amongst so many other things.)
Some things that help include and keep improving are:
- multiple front end modules (more simultaneous bands)
- multiple CMOS radios (more spatial dimensions)
- multiple antennae or antennae diversity (better spatial powers or
eigen values)
- more radio heads (less media contention, much lower latency)
These are some of the "easy" things to engineer and we still have a lot
more to do to catch up with Paul's and other's ideas (who were and are way
ahead of their time.)
Bob
On Fri, Feb 23, 2024 at 7:54 AM Dave Taht via Make-wifi-fast <
make-wifi-fast@lists.bufferbloat.net> wrote:
> It is still not well understood that wifi performance is dragged down
> by the performance of the most distant and demanding device, despite
> what I hope is wide knowledge of the wifi performance anomaly (
> https://ieeexplore.ieee.org/document/1208921 ) and the related work in
> "Ending the anomaly".
>
> It occurred to me, today, while wrestling with a tv struggling to
> stream 4k video over wifi, that perhaps it was possible to determine
> what tvs had more than one wifi antenna, and how well they were being
> used (total airtime).
>
> Is anyone tracking that? Simple methods like scraping the sales lit
> might be used, and or instrumenting the APs.
>
> --
> https://blog.cerowrt.org/post/2024_predictions/
> Dave Täht CSO, LibreQos
> _______________________________________________
> Make-wifi-fast mailing list
> Make-wifi-fast@lists.bufferbloat.net
> https://lists.bufferbloat.net/listinfo/make-wifi-fast
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