On Fri, Jan 16, 2004 at 04:35:21PM +0200, Ivan Korshun wrote: > Brian Lloyd wrote: > > For example: > distance from Earth to Moon = ~384000km, > then : > > > >> 41 dBm EIRP (20dBm + 21dBi) at his house. > > >> - 108 dB Free space loss - first link > > Free space loss from Earth to Moon = -227dB > > > >> + 18 dBi antenna gain on the mountain. > > >> + 18 dBi antenna gain on the mountain. > > >> - 118 dB Free space loss - second link. > > Free space loss from Moon to Earth = -227dB > > > > >> + 24 dBi antenna gain at ISP. > > >> ========= > > >> - 125 dBm > > total : - 454 dB Free space loss ... > > Communication impossible, > even if to use "1Hz or less bandwidth" > & "symbol rate is about one symbol every 10 seconds"
And yet, hams have been doing successful EM or 'moonbounce' communications since, ok, the 60's or earlier. Curious, isn't it? Perhaps your math is wrong? http://directory.google.com/Top/Recreation/Radio/Amateur/VHF/Moonbounce/ Cheers, -- jra -- Jay R. Ashworth [EMAIL PROTECTED] Member of the Technical Staff Baylink RFC 2100 The Suncoast Freenet The Things I Think Tampa Bay, Florida http://baylink.pitas.com +1 727 647 1274 Come see Linux Gazette in our new home: www.linuxgazette.net! -- general wireless list, a bawug thing <http://www.bawug.org/> [un]subscribe: http://lists.bawug.org/mailman/listinfo/wireless
