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Old May 18th 05, 08:03 AM
Dana H. Myers
 
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Marty Albert wrote:

For the life of me, I can see no reason why Frank's device could not be
re-designed today to well over 512 Mbps, perhaps very close to gigabit
speeds. If you make the jump to the new copper solutions for 10 Gbps, we may
even be able to get close to that...


What was the on-the-air bandwidth of Frank's 80Mbps signal?


Dana K6JQ
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Old May 19th 05, 05:26 AM
Marty Albert
 
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As I recall, at 23 cm and 80 Mbps we had an effective bandwidth of around
100 KHz on the "final" design... That design incorporated TDM, limited SS,
and WDM of the signals.

Obviously, with multiple forms of simultaneous multiplexing, the bandwidth
would through the roof, most likely to around 100-150 MHz.

Today, we could use TDM, WDM, SDM, high-end SS, and a few other tricks and,
assuming a target data-rate of 100 Mbps, get the on air bandwidth down to
around 50-75 KHz, maybe even a little less.

With a similar set up except for a target data-rate of 10 Gbps, my
back-of-the-envelope calculations are coming up with an on air bandwidth on
the order of 30-50 MHz.

There may be as much as a 10-15% decrease in bandwidth by using a well
designed DSP.

Essentially we would need to look carefully at the Ethernet 10+ Gbps over
copper and copy those concepts... I have my upper division and grad students
looking at ways to do just that.I am hoping in the next month or so, I can
reach an agreement with EE department and the RF engineering department to
bring in some of their students to help out with those aspects... My
students have already found one thing... BASIC Stamps and PIC processors
will only work up to about 115 Mbps. Beyond that, they are just too slow.

Take Care & 73
--
From The Desk Of
Marty Albert, KC6UFM



"Dana H. Myers" wrote in message
...
What was the on-the-air bandwidth of Frank's 80Mbps signal?

Dana K6JQ



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Old May 19th 05, 07:04 AM
Dana H. Myers
 
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Marty Albert wrote:
As I recall, at 23 cm and 80 Mbps we had an effective bandwidth of around
100 KHz on the "final" design... That design incorporated TDM, limited SS,
and WDM of the signals.


What exactly does this all mean?

Passing 80,000,000 bits/sec in 100,000Hz of bandwidth sounds
pretty fantastic - to the extent that makes me question the
validity of the measurements.

Today, we could use TDM, WDM, SDM, high-end SS, and a few other tricks and,
assuming a target data-rate of 100 Mbps, get the on air bandwidth down to
around 50-75 KHz, maybe even a little less.


Whoa. Hold on. Help me understand what units and methods
of measurement you're using. Right now, you're off by several
decimal places in even the most generous way.

Dana K6JQ
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Old May 18th 05, 08:07 PM
n3soz
 
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Marty,

Yes I am drooling over the possibility. Like you I can imagine these
fantastic star networks ringing the big metro areas. I think though
that to be feasible the community needs to look at whats available
off-the-shelf. Obviously if someone technically brilliant can take
Frank's idea and build something that can be cheaply manufactured, that
would be ideal. But Icom's D-Star system is available, and hams are
using 802.11 access points with amplifiers and directional antennas
(www.arrl.org/hsmm/). Maybe a club somewhere has a network like this
already running. It would take a dedicated group of hams with some
fairly serious resources (capital, access to good sites, know-how) to
pull something like this off.

In my area a small group of ATV guys have put up a repeater, and have
established several sites at EOC's, with the goal of providing ATV
"on-demand" to emergency officials. A network project could piggyback
on something like that.

Matt, N3SOZ



Marty Albert wrote:

For the life of me, I can see no reason why Frank's device could not

be
re-designed today to well over 512 Mbps, perhaps very close to

gigabit
speeds. If you make the jump to the new copper solutions for 10 Gbps,

we may
even be able to get close to that...

Imagine a large metropolitan area, like maybe Dallas/Fort Worth,

ringed by
an 8 Gbps nodes with spokes at 8 Gbps "dropping" into and through the

city.
A series of 1 Gbps nodes come off of the spokes to feed into the
neighborhood. In the neighborhoods, picture a bridge node that users

can
connect to at, say, 100 Mbps. Lastly, picture these "City Wheels"

being
connected to other city wheels at 10 Gbps.

Are you drooling yet?

Take Care & 73
--
From The Desk Of
Marty Albert, KC6UFM



"n3soz" wrote in message
oups.com...
I've been a ham for almost eleven years. The year I got started

(1994)
was the same year the Web became open to commercial traffic, and I
guess the decline of packet began around that time. I keep an APRS

snipped for space's sake


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Old May 19th 05, 05:44 PM
Hank Oredson
 
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"n3soz" wrote in message
oups.com...
Marty,

Yes I am drooling over the possibility. Like you I can imagine these
fantastic star networks ringing the big metro areas. I think though


So do it!
WiFi gear getting cheap, run it within the ham band.
Works fine.

that to be feasible the community needs to look at whats available
off-the-shelf. Obviously if someone technically brilliant can take
Frank's idea and build something that can be cheaply manufactured, that
would be ideal. But Icom's D-Star system is available, and hams are
using 802.11 access points with amplifiers and directional antennas
(www.arrl.org/hsmm/). Maybe a club somewhere has a network like this
already running. It would take a dedicated group of hams with some
fairly serious resources (capital, access to good sites, know-how) to
pull something like this off.

In my area a small group of ATV guys have put up a repeater, and have
established several sites at EOC's, with the goal of providing ATV
"on-demand" to emergency officials. A network project could piggyback
on something like that.

Matt, N3SOZ



Marty Albert wrote:

For the life of me, I can see no reason why Frank's device could not

be
re-designed today to well over 512 Mbps, perhaps very close to

gigabit
speeds. If you make the jump to the new copper solutions for 10 Gbps,

we may
even be able to get close to that...

Imagine a large metropolitan area, like maybe Dallas/Fort Worth,

ringed by
an 8 Gbps nodes with spokes at 8 Gbps "dropping" into and through the

city.
A series of 1 Gbps nodes come off of the spokes to feed into the
neighborhood. In the neighborhoods, picture a bridge node that users

can
connect to at, say, 100 Mbps. Lastly, picture these "City Wheels"

being
connected to other city wheels at 10 Gbps.

Are you drooling yet?




--

... Hank

http://home.earthlink.net/~horedson
http://home.earthlink.net/~w0rli




  #6   Report Post  
Old May 19th 05, 07:34 PM
news
 
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In message et, Hank
Oredson writes

So do it!
WiFi gear getting cheap, run it within the ham band.
Works fine.


Hank (or anyone else),

Can you point me to reflectors/forums for WiFi ham band networks? I
would like to catch up with what people are doing in this area.

73
Ian, G3NRW

  #7   Report Post  
Old June 18th 05, 07:15 PM
Bill Turner
 
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Marty Albert wrote:

I am curious as to what people attribute the (apparent) death of
digital systems overall.



_________________________________________________

The "new" has worn off. When a new mode or technique appears, traffic
will pick up again.

--
Bill, W6WRT
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