[aprssig] REF:Packet on the ISS & PK900

[Peter Laws N5UWY]

On Sat, Feb 29, 2020 at 11:39 AM Steve Dimse <steve at dimse.com> wrote:

>
> There are plots of the X30 gain on the Diamond web site, google "X30 gain pattern". You will see by the time the ISS is over about 30 degrees the gain has gone negative. Most of the time satellites are below 30 degrees, but the slant range is greater. Also, a unique problem with ARISS is the antenna is not in the clear, so the best chance of working it is when it is much higher in the sky so that other parts of the ISS are not obstructing the signal and it is closer to you. Those times when the ISS is in the best position your antenna has gain down 26 db! So this antenna, and all gain omindirectional antennas, are not the best for satellite work.

Some dude named "Bob" has a paper on this:   http://aprs.org/LEO-tracking.html

-- 
Peter Laws | N5UWY | plaws plaws net | Travel by Train!