I'm doing this from memory having looked at it some time ago and with Wiki being switched off.
The accuracy of a SatNav will be affected by a number of factors one of them being the number of satellites its working with, the more satellites the more accurate the location.
For speed accuracy is improved with the frequency of communication between the SatNav and the satellites. This is the bit the allows the military to send missiles around the world to with a few feet of target. Just looked it up and the accuracy of a domestic satnav is +/- 10 metres whereas the military is less than 1 metre.
Translating that into road speed accuracy will be an issue.
On that note I went to see a client today whose wife works in a scammervan department.
He tells me that her department is set to becoming self funding from the revenue received through driver training courses.
You'll be surprised to hear that in this particular police area the number of people attending driver training has risen significantly and is being looked at as the model for other forces.
