I would like to see a better explanation for how clients can talk to the AP over many kilometers. Just by the AP having a "big ass antenna" won't cut it, since by then, the received signal is weak, and amplifying it (say, 14 dB or more via an antenna) will amplify noise as well.
Rough estimates: 30 mW transmission like in Orinoco cards(100 mW being peak) = just under 15 dBm. Losses in free space, assuming Line of Sight, are 106.5 dB for 2 km. So, signal is down below -90 dBm. At this point, signal to noise ratio will kill you, regardless of ANY gain from the receiver at the AP.
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I would like to see a better explanation for how clients can talk to the AP over many kilometers. Just by the AP having a "big ass antenna" won't cut it, since by then, the received signal is weak, and amplifying it (say, 14 dB or more via an antenna) will amplify noise as well.
Rough estimates:
30 mW transmission like in Orinoco cards(100 mW being peak) = just under 15 dBm.
Losses in free space, assuming Line of Sight, are 106.5 dB for 2 km.
So, signal is down below -90 dBm. At this point, signal to noise ratio will kill you, regardless of ANY gain from the receiver at the AP.
Peace