Why is the response dubious. Remember this isn't a two way system. It is more like broadcast sat TV but for information.
2.4 Ghz is fine for sat downlink (remember one direction only).
For example one sat radio system runs on L brand which is 1 to 2 Ghz.
http://en.wikipedia.org/wiki/WorldSpaceThat is a full sized sat with much higher power levels.
And this is a full sized sat runing on much higher power levels. And neither of them use the B/G wifi band, which as I have alrady noted, is
heavily attenutated by water and hydrocarbons in a way that the rest of the S band is not, and is the primary reason that said band is unlicesned to start with.
The best comparison that we might have for a setup that would work woudl be a ham radio sat. Here's one to compare...
http://www.amsat.org/amsat-new/satellites/sat_summary/ao51.phphttp://en.wikipedia.org/wiki/AO-51This one uses several transmitters, but keep in mind that not only is this device using much narrower bandwidths, it's not attempting to transmit continuously. So putting out a 38 Kbps data signal at 300+ watts RMS for an average of a minute or two per hour is within the power requirements of a mini sat that has a 30 watt solar panel.