Arduino radar using GPS

Hey everybody, i'm a newbie in arduino
I have a project to build a system that can track a positition of a car between 2km radius. is like a radar. but only car fitted with this device that will be tracked
Can i make that system with just a GPS and zigbee?
if anyone ever made ​​a project similar to mine ?
Please share codes or tips to realize my project
Thank you

Nothing legal is going to give you 2km range in from a moving car in a built up area

IMHO the only thing that is likely to work is mobile phone GPS using mobile phone data.

Basically write a mobile phone app to do this (I suspect one already exists)

MotionX used to (my old app still works) be able to stream updated GPS data to another mobile user. Check them out. They have a free version that may still work.

Or, you could just go onto a surveillance supply site and get a GPS tracker there. That seems to be the route you're going anyways.