2D Doppler Shift / Relative Velocities

[awelex]

Hi,

I'm trying to adapt the doppler shift formula for a stationary listener and a source traveling in a straight line towards/away from the listener to the case where the source does not move straight towards the listener. For example, suppose that I am looking north and train further in the distance moves from west to east.

The frequency factor in the 1D case is \frac{v}{v - 333m/s}. The only thing that changes in the 2D case is that we can't no longer use the absolute velocity v of the source, but have to use the relative velocity with respect to the listener. But this is where I'm stuck: How do I compute this relative velocity when the listener is stationary? Wouldn't that mean that v_{rel} = v_{abs} - 0 = v_{abs}? That obviously can't be true.

Thanks,
Alex

 

[Bobbywhy]

Please check on how air intercept missiles perform their mission using the target's line of sight rate change, along with the doppler shift. Hope this textbook helps explain the process:
http://books.google.com/books?id=NV...=onepage&q=doppler line of sight rate&f=false

Cheers, Bobbywhy