RayW
Premium
join:2001-09-01
Layton, UT
clubs:
 ·XMission
| That is one hefty carrier!
Looking at the spectrum analyzer display, they show an ordinary FM broadcast signal down in the mud, and the xMax carrier about 50 dB greater than the FM broadcast signal.
Of course we do not know what the relative distances are, but while we know that signals in the mud can provide useful data (hand held GPS units come to mind), multiple high bit rate data? Even with a powerful 'coordination' channel, I think they will have problems, especially if there is a lot of traffic.
The site has some interesting facts mixed in with some items that sound good, but look questionable. Not having worked in RF design for a long time, all I can say is - 'Do not invest your money unless you can stand to loose it'.
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I am not lost, I find myself every time. |
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rf_engineer
join:2003-08-04
USA
| said by RayW  :Looking at the spectrum analyzer display, they show an ordinary FM broadcast signal down in the mud, and the xMax carrier about 50 dB greater than the FM broadcast signal. I've wondered about this, too. This seems to be another "the data is in the sidebands, ignore that fat carrier in the middle, it's just a clock" system. I'm curious about their power level claims. Do their figures include the clock carrier? |
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AJ023
join:2001-12-25
Forest Hills, NY
| reply to RayW
The credibility of those involved is enormous.
We shall see what happens since they claim a working device will be out the middle of this year.
Either it works which would revolutionize broadband delivery, or it will fail. Startups like this have a risk factor. For every 10 that come out, only 1 will succeed or maybe even less. For rural areas and areas without broadband it makes more sense especially for inhome usage.
In my case for residential I have inbuilding fiber to my basement and coaxial up to the apartment. So in my case, for lets say less than 1k feet of distance, this technology really doesnt change anything.
I wish the best of all these companies whether it be nethercomm, XG Technology, companies working on BPL, and the like. If something hits it right, we shall see from so far all of these types of companies have fallen on their faces. |
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rf_engineer
join:2003-08-04
USA
| said by AJ023 :The credibility of those involved is enormous. Do you really mean their credibility is enormous, or are you implying their credibility is at stake (serious question)? It looks like the principles involved in this venture have been down this road before:
»www.theregister.co.uk/2005/11/09/xmax/
I'm not implying this is fraudulent, but at this point there's not much credibility to go on, unless you know of some public information showing otherwise. |
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