WiMAX:
The IEEE 802.16 Air Interface Standard is truly a state-of-the-art
specification for fixed broadband wireless access systems
employing a point-to-multipoint (PMP) architecture.

In order to ensure interoperability between vendors equipment, the
WiMAX technical working groups have completed the work for 10 to
66 GHz and has started work for the sub 11 GHz part of the
standard.

This requirement eases the effect of multipath, allowing for wide
channels, typically greater than 10 MHz in bandwidth.

The standard is designed to accommodate either Time Division
Duplexing (TDD) or Frequency Division Duplexing (FDD) deployments,
allowing for both full and half-duplex terminals in the FDD case.

The MAC [Media Access Control] was designed specifically for the
PMP wireless access environment. It supports higher layer or
transport protocols such as ATM, Ethernet or Internet Protocol
(IP), and is designed to easily accommodate future protocols that
have not yet been developed. The MAC is designed for very high bit
rates (up to 268 mbps each way) of the truly broadband physical
layer, while delivering ATM compatible Quality of Service (QoS);
UGS, rtPS, nrtPS, and Best Effort.

The 802.16 MAC uses a variable length Protocol Data Unit (PDU)
along with a number of other concepts that greatly increase the
efficiency of the standard.

Practical cell sizes usually have a small radius of around 5 miles
or less.

Data rates vary according to modulation rates (1.75MHz to 20MHz)
and modulations (QPSK and QAM) to achieve 1Mbs to 75Mbs.

73's
Richard Clark, KB7QHC

"Richard Clark"
Practical cell sizes usually have a small radius
of around 5 miles or less.

www.google.com/search?q=Wi-max+miles
www.google.com/search?q=%2B802.16a+miles

Getting a lot of hits for "30" miles.

This doesn't contradict your quote, just expands upon it.

For a house in the woods with a suitable high gain antenna, the max range
could tend towards the extreme distances. For IP to cars, less.

On Wed, 20 Oct 2004 22:28:27 -0300, "Beth McBob"
wrote:

Getting a lot of hits for "30" miles.

This doesn't contradict your quote, just expands upon it.

Hi Beth,

The reason why it is inspecifically cited as "practical" is that
throughput is negotiated against distance and greater demand against a
constant capacity. If you want to share the same resource with 33
times more customers, you have to accept 3% the bandwidth. Classic
Cellular Telephone history. BPL couldn't possible keep up with
terabyte demand, star configurations against fiber optic trunks will
prevail.

I really get a hoot out of correspondence here comparing BPL to
advances in science like Penicillin, when it is more like the legacy
of Thalidomide. Folks thought that was a miracle drug too.

73's
Richard Clark, KB7QHC

I really get a hoot out of correspondence here comparing BPL to
advances in science like Penicillin, when it is more like the legacy
of Thalidomide. Folks thought that was a miracle drug too.

73's
Richard Clark, KB7QHC


I don't recall seeing anything like that. Can you cite the link? It doesn't
show up on a google search on any NG I have found.

Have a lovely day.
Chip N1IR

"Richard Clark"
If you want to share the same resource
with 33 times more customers, you have
to accept 3% the bandwidth.

Excellent point.

Of course, to start, they could put up one site and let it evolve from
there. 56Mbps / 33 is still 1.7 Mbps (perfectly acceptable). Even 333
clients is still much better than dial-up. Also, those 333 clients probably
have other things to do beside 100% downloading music and p0rn, and so you
can add a huge (or 1/huge) duty-cycle factor (worse at prime time). In other
words, one 56Mbps access point is capable of serving MANY clients (a
wireless MAN). The future dividing into smaller cells is a nice bonus that
can be paid for with cash already earned from the first installation. Thus
Wi-Max is going to be ~huge~ because the finances are incredibly good (waaay
better than cell phone since the sites are going to be sooooooo much
cheaper, one or two orders of magnitude cheaper, a guess).

BTW, if the 'last mile' is such a big problem, then how come the Cable TV
companies are so damn rich? Duh. Run the damn optical fibres and 'clean up'
the whole market for fixed access. Nothing beats optical (so far).

Didja see the 'interesting tidbit' about non-HF 'BPL' ? Sounds much nicer
than the HF-crap system.

On Thu, 21 Oct 2004 18:57:11 -0300, "Barb McBarb"
wrote:

BTW, if the 'last mile' is such a big problem, then how come the Cable TV
companies are so damn rich?

Hi Barb,

If they are so damn rich (arguable proposition given how many times
mine has been traded), it was from an investment now 20 years old.

If someone took the plunge and hooked fiber optic to every house in
the city, I am sure they would be damn rich in 20 years too. Problem
is with regulation. It existed then, it doesn't now.

BOTH the democrats AND the republicans walked away from the problem 6
years ago to leave it up to "market forces." This was like tossing
money at street bums to help them sober up. The corporate welfare
state stumbled along content with the status quo, happy to sew up
their constituencies knowing competition had a huge energy well they
had to climb out of to simple enter the market.

However, this also reveals the poverty that exists in the minds of
these welfare queens. They think in terms of their own solutions -
wire to the house (or fiber optic to the house). Not looking any
further than their own preconceived failure, they presume everyone
else will fail similarly. This dinosaur mentality reveals itself in
the BPL "wiring" opportunity. RF will eclipse their Jurassic ideas
and they will demand an "even playing ground" (familiar cry of the
entitlement addict) as the mammals gnawing on their ankle bones start
to work on their haunches.

We need to outsource more boardroom jobs to those with quicker minds
willing to actually work harder to be more productive for less.

73's
Richard Clark, KB7QHC

We need to outsource more boardroom jobs to those with quicker minds
willing to actually work harder to be more productive for less.

73's
Richard Clark, KB7QHC


Hi Richard,

What's YOUR job:-)?

73,
Chip N1IR