1
$\begingroup$

Does someone have a table with doppler shift range for satellite communication systems?

Is it S band or X band?

I have seen somewhere, but I can't find it.

$\endgroup$
1
  • 1
    $\begingroup$ the band used doesn't tell you which kind of orbit your commsat is using; a Molniya orbit satellite will have a different Doppler signature than a satellite in geostationary orbit, and differet from a satellite in near-spherical LEO; and all three could be using the same bands. $\endgroup$ Mar 22, 2022 at 7:22

1 Answer 1

4
$\begingroup$

I would recommend playing around with one of the predict libraries e.g. https://github.com/nsat/pypredict You can go find a TLE of a satellite you're interested in from a public database, and enter ground coordinates and time to compute the relative velocity (doppler offset), acceleration (doppler rate), jerk (doppler acceleration) etc.

To put some numbers to it, I typically consider S-band (2GHz) doppler at LEO to be a maximum of around +/- 100 kHz or so (corresponds to around 15 km/sec of relative velocity). But it really depends on your orbit, altitude, and ground location - which is why I recommend the above tool. With a typical overhead pass of a satellite over a ground station, the doppler profile will look like an inverted S-curve. It will start off with a maximal positive doppler shift (i.e. maximal relative velocity) as the satellite comes up over the horizon. The shift will eventually start decreasing quickly as the satellite passes over head (this is where the doppler offset is zero and the satellite acceleration (doppler rate) is maximal) until it heads back toward the horizon and towards its maximal negative doppler shift.

$\endgroup$
0

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.