In message <[EMAIL PROTECTED]>, Magnus Danielson writes: > Once doppler bin and phase has been achieved for each PRN, [...]
Just a footnote to say that as soon as you start receiving ephemerides from the first sat, the search-space can be significantly reduced if you care to do the, rather longhaired, trignometric math. >A sat based receiver must handle higher doppler offsets due to its >higher speed, [...] While this is true for any non-geo-stationary satellite, it may not be true for the project the initial poster talked about. As I remember it, he said that the mission would be in an earth-following orbit, ie: in the same orbit as the earth around the sun, but trailing it by some distance. Given that the distance in GPS terms is "vast" and furthermore that the GPS orbits have a pretty steep angle relative to the earths orbital path, I would expect the doppler offsets to be much smaller than here on earth. Obviously, getting a position fix will suck with the worst DOP seen to date, but a frequency fix should not be out of the question. Obviously, the situation on the way to the final orbit is entirely different, and there I would expect doppler to be totally out of the lower end of the window. Remember to figure out the relevant relativistic corrections. Poul-Henning -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 [EMAIL PROTECTED] | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.