On Sat, 13 Nov 2004 23:42:26 +0000, Mike wrote:

In message , Matthew
Maddock writes

Or you could simply fake a plate that looks like a real one - so how will
the "automatic detection" know if a car is there or not ?

Because the device reading the microchip will not detect its existence in
the plate. Simple - if it ain't there, then it is fake!

From the transponder reader's pov, what's the difference between a car
without a transponder and an empty space without a transponder?

Mass? Temerature? Capacitance? The transponder reader would have to be
combined with a vehicle detector of some sort to prevent fraud.