Paul Keinanen wrote:
Assuming ordinary +20 dBm cards with 16 dBi antennas at both ends, you
would end up to the +36 dBm EiRP (4 W) transmit power.

Which puts you right at the legal limit for the U.S. If your transmitter
is slightly higher power, or the antenna is more efficent you go over
the limit.

The free space
loss at 32 km and 2.45 GHz is 130 dB, so the receiver would get -94
dBm, which is very little for broadband traffic, especially that
figure does not contain the fade margin. In fact using +10 dBm cards
and 26 dBi antennas would give 10 dB more receiving power.

If I understand you correctly the EIRP would remain the same?

Around 1980 I worked a place that used IR beams for high speed (4800bps),
data and it worked until someone built a hotel in the way. :-)

Geoff.

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Geoffrey S. Mendelson, Jerusalem, Israel N3OWJ/4X1GM
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