Internet via the mains net ? 1

[walker1]

I have heard and read about this way of supplying internet to the users, but can anybody give an expl. of how the 'backbone' of it works ?

Do you simply use the existing copper along the roads?
(In the US that is usualy in the kV area.)

What kind of carrier wave is used (freq. band)

Signal level ?

How about radio noise spreading from these miles long antennas ?
(We do have quite a lot of radio polution already from cell phones, bluetooth, wireless networks/keyboards/pointing devices etc.)

How about transmission loss ?
(We are not talking shielded or twisted pairs here)

A web address about this would be helpful, as I have now been asked about this by a couple of people.

 

[tinfoil]

Low technical content, but look at :

http://www.hometownconnections.com/utility/broadband.html

and

http://news.zdnet.com/2100-3513_22-5163739.html

and

http://www.cbc.ca/stories/2003/11/21/Consumers/power_lines031121

and

http://www.newsfactor.com/story.xht...oves-Internet-over-Power-Lines&story_id=27662

and

http://www.eham.net/articles/9013

 

[mc5w]

Internet using Power Line Carrier has been tried in a number of places and all of these have been failures due to interference to aircraft radios, police radios, amateur radios, and so forth.

If a signal is strong enough it will force its way into any radio even if it is tuned to a different frequency. Strong radio signals can also force themselves into any analog equipment that does not have tuned circuits. I had an instance where WQMX-FM forced its way into a public address system that was in the next county.

There is also another problem that some utilities such as Ohio Edison already use powerline carrier on their distribution lines to control capacitors. Leviton's and Radio Shack's home automation/remote control systems are unusable on Ohio Edison's system unless you are supplied from a dedicated padmount transformer and your service lateral runs in the opposite direction from the primary - the home controls use the same frequencies and protocols as the capacitor controls.

Mike Cole, mc5w@earthlink.net

 

[jon1]

It does work, but only for short hops, and the FCC hasn't yet licensed the technology, because it does have some spread spectrum radiation (low band). For more info, visit:

http://ambientcorp.com

 

[jraef]

nteresting link, but I wish they had picked a different actonym besides "PLC". I see nothing but confusion arising from that...

"I need to connect my PLC to my ISP using TCP/IP with a PLC..."

"Venditori de oleum-vipera non vigere excordis populi"

 

[jraef]

My typing sucks today...

"Venditori de oleum-vipera non vigere excordis populi"

 

[automatic2]

Here in Alberta Canada, thousands of miles of fibre optics have been installed to create the digital arteries. High speed/high quality is a must to be considered a worth while investment.

 

[Rich2001]

Here are a few links that should be of interest: (Amateur Radio slant)

http://www.arrl.org/tis/info/HTML/plc/aud-vid.html

http://www.arrl.org/news/stories/2004/06/18/8/BPL-and-HF-web.mpg

http://www.rac.ca/news/barry.zip

http://www.qrpis.org/~k3ng/bpl.html

http://www.arrl.org/tis/info/HTML/plc/files/BPL_paper.pdf

http://www.wave-report.com/tutorials/bpl.htm

http://www.wave-report.com/other-html-files/citipowerline2.htm

http://www.wave-report.com/other-html-files/citipowerline3.htm

http://www.arrl.org/tis/info/HTML/plc/BPL-leave-behind.pdf

 

[Skogsgurra]

I have had problems with the remote metering systems that are being tested over here. They use a pair of carrier frequencies in the band between 50 and 100 kHz (or close to). Frequency hopping is used to avoid problems.

The problem is that there are problems all over that frequency range. So it does not work very well. Frequency inverters and low-energy lamps are the worst polluters. And if you apply filtering to get rid of the interference, guess what? You also filter the communication signal away!

My personal opinion is that Power Line Communication will never work for the Internet. It just barely works for metering purposes, which is a low-speed application with a few kilobytes of data being transmitted occasionally.

"Power Line ADSL" is an engineers pipe dream.

 

[2dye4]

I do not see how this system will work.
A 12kv power line is not impedance controlled
at data frequencies. What about where power lines
tee off to other neighborhoods. This is not allowed
in a real data tranmission line because it
creates a mismatch. How can this equipment be
designed to bypass the distribution transformer with
data and still be economical. If this bypass fails
you could die while surfing the net.
I am sure this can be made to work in a few places
for long enough to interest a lot of investors with
more money than sense but can it really serve
enough people to be profitable given the cost??