abward
join:2004-07-14
Cary, NC | News flash: local toddler fried touching internet antenna
I guess I don't get it. It takes something like a million watts to broadcast a signal in a 50 or so mile radius, to reach my TV...one way. Do I need to install a 5kw or whatever transmitter to get the signal back to that tower? |
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wnorman
join:2002-01-30
Macclenny, FL
| I was wondering the same thing. This spectrum is used to broadcast a signal to users, but communication has never been two way. Will this be similar to the old DirecPC where you have decent download speeds, but need a phone line for upload? Does anyone know the details about how upload is accomplished with this technology? |
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PDXPLT
join:2003-12-04
Banks, OR
| reply to abward
said by abward  :I guess I don't get it. It takes something like a million watts to broadcast a signal in a 50 or so mile radius, to reach my TV...one way. No it doesn't. That 1 million watts is EIRP, Effective Isotropic Radiatoed Power. In other words, the signal strength that would be obtained if that amount of power was fed into an antenna that radiated equally well in all, 3-dimensional, directions.
In reality, that TV station antennas focus all their signal strength in a narrow vertical beam aimed at the horizon; very little is sent down to ground level or up n space (that's why neighborhoods near TV antennas don't get hit with very high radiation levels). For a 1 million watt EIRP station, the actual transmitter output is more like 200 KW.
And with that signal, they can go around hills, through trees, and hit the rabbit ears in your basement. With a TV signal that needs a 40 dB Signal to Noise Ratio to look decent.
OK for a WISP application you may need an exterior antenna, aimed at the WISP tower. Most people without broadband would gladly do this, and according to the FCC OTARD Rule, no local gov't or HOA can stop them from doing so. |
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danielhays
join:2006-12-07
Clintwood, VA | Would this work with satellite television? (DirecTV) Sounds crazy to me. |
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