according to the free space path loss equation:
LdB = 20log(4*pi*d*c/f)
where c=speed of light (or radiated waves in this case) in m/s
d=distance from source in m
f=frequency in Hz
pi=3.1415926535
for 1km @ 2518000MHz
LdB_1km = 20log(4*3.14159265*1000*2518x10^6/3x10^8) = 100dB
LdB_3.5km = 111dB
(my figures are at 3.5km for my tower and about -90dBm signal)
conclusion, with -90dBm received and 111dBm lost, they are pumping out 21dBm (125mW) PER MODEM
the difference close to tower versus far away is only 10dBm which is a little more than the gain using a cantenna.
technical details aside, I dont think overwhelming is accurate. overshooting yes. the tower radiates with an aperture (or whatever you call it) size with a certain amount of degrees horizontal and also vertical per sector. thus at close proximity you may lose some signal yes.
ALSO
plug 500m into the equation => LdB = 94dB
and 100m => LdB = 80dB
and 10m => 60dB
and 1m => 40dB
and finally, 6.5km => 116.7dB
which means that most of the signal is lost right at (and around) the tower. you will get fried if you stand up against a sector panel.
1km away is the perfect distance. Im too lazy and busy to generate a graph but im sure 1km is close to ideal for 50% signal strength.
Donovan, nice but shame. can you imagine the testing issues that are gonna arise. ouch. and you will *never* see another tower. shame..
btw, dB is a signal power scale. if in doubt, www.justf*ckinggoogleit.com
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