[MLB-WIRELESS] Fw: AusCTW report

[Craig Mead]

(thanks to Mr Dalton from the Sydney List)


----- Original Message -----
From: "John Dalton" <john.dalton at bigfoot.com>
To: <syd-wireless at lists.sydneywireless.com>
Sent: Monday, February 10, 2003 9:04 AM
Subject: [Syd-Wireless] AusCTW report


> Hi all,
>
> I've just gotten back from the Australian Communication Theory
> Workshop.  Nearly all theory and complicated matrix equations,
> but some points of interest to Sydney wireless came up.
>
> There was a claim that practically none of the '54Mbit/s' WLAN
> cards on the market will actually reach the 54Mbit/s mode (even
> under perfect conditions) as they are internally limited by
> noise and other such things.  Generally 36Mbit/s is their maximum.
> Rumor has it that one vendor's cards can reach 54Mbit's but I got
> the impression that even then 54Mbit/s could only be reached under
> laboratory conditions.
>
> 100Mbit plus cards are not too far from market.  The MAC layers
> in some WLAN cards already have the hooks in place to integrate
> a space-time (multiple antenna) based physical layer.  Using
> existing 20MHz (approx.) channels, such cards should be able to
> push 400Mbit/s plus, though the first generation will probably not
> be anywhere near this speed.
>
> Stating the obvious.  In the longer term, WLAN manufacturers will
> be releasing cards to use the higher frequency bands: 10GHz, ..., 60GHz.
> They are relying on lower frequency bands filling up, and fueling
> demand for the new hardware.
>
> Also I was talking to a guy who claimed that a dense mesh using
omnidirectional
> antennas has been proved mathematically not to work.  Apparently the
> interference between users rises faster than the signal, so throughput
> eventually falls to zero.  Note that this does NOT say that a mesh of
> directional antennas will not work.  I don't have a reference for the
> paper he referred to, so until then take the above point with a grain of
salt.
> There may be some assumptions made in the paper which make it inapplicable
to
> practical networks.
>
> Regards
> John
> _______________________________________________
> Syd-Wireless mailing list
> Syd-Wireless at lists.sydneywireless.com
> For account administration (such as removing yourself from the mailing
list and changing your email address)
> http://lists.sydneywireless.com/mailman/listinfo/syd-wireless
>
> Proudly supported by http://www.AustWireless.com
>


To unsubscribe: send mail to majordomo at wireless.org.au
with "unsubscribe melbwireless" in the body of the message