> Hmm... Let's calculate it...

http://www.nrl.navy.mil/content.php?P=MOONRELAY
 
> He states in the article that he is using a WAP11 at his house
> running at 100mW (too bad as a WAP11 splatters all up and down the
> band in this mode and he is likely violating the FCC's spectrum
> requirements) into a 21dBi dish.  The mountain top is 1.5 miles
> away.  He is using some sort of yagis on the mountain top.  The
> second path is 5 miles.  He doesn't state the gain of the yagis or
> what the antenna is at the ISP.  But we can make some assumptions...
> 
> Ignoring cable/connector losses at his home he is doing 41dBm EIRP
> out of his antenna (20dBm + 21dBi).  The free space loss at 1.5
> miles is about 108 dB. Lets assume his yagis are 18dBi and there
> is no loss on the cable connecting them together.  The 5 mile path
> will have a free space loss about 118dB and we will assume he has
> a 24dBi gain antenna on the roof of the ISP.  Lets add this up...
> 
>            41 dBm EIRP (20dBm + 21dBi) at his house.
>         - 108 dB  Free space loss - first link
>         +  18 dBi antenna gain on the mountain.
>         +  18 dBi antenna gain on the mountain.
>         - 118 dB  Free space loss - second link.
>         +  24 dBi antenna gain at ISP.
>         =========
>         - 125 dBm

According to these calculate communication
through the moon is impossible ...

Really communication is,
even if to use 10W

-Ivan
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