You know I am not quite sure how to answer that..

Doppler shift is a relative thing. If you are travelling at 100kph the
signal/carrier whatever relative to you is unaffected. Relative to a RX
that is relatively moving either towards or away from you a shift will
be apparent.

The entire transmitted spectrum will be affected, not just the
"carrier". There will of course be a calculable difference in shift over
the bandwidth of the signal as the lower end will shift less than the
upper one more. Whether it will be a significant amount or not depends
on your application. A +- 10MHz wide signal at 2.4GHz for example
(100kph) would be close to an extra 1Hz of shift at the signal edges.

As your relaitive velocities approach the speed of light other problems
crop up. I dont quite remember Einstein's stuff on this. Since though I
doubt I'll never get to experiment with it I dont need to go through it
again!

Is that what you were looking for?

Cheers Bob VK2YQA

K7ITM wrote:

Bob wrote, "You'll get about +-200Hz shift with a speed of 100kph."

Ahem. Care to qualify that as to the carrier or transmitted
frequency??