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Re: Exhibition Street Bridge and City Link

On 22 Oct 1999 09:13:12 GMT, cmgord@ecr.mu.oz.au (Christopher_Martin
GORDON) wrote, and I selectively quote:

>But you only have about 1 second to read e-tag (this works), process (tolling
>computer too slow) and transmit to e-tag (this works)and it takes about 2-3
>seconds then the car at 100 km/h has gone too far down the road before the
>information to transmit back to the e-tag is ready.

I wonder if this is the only problem.

If it was, the simple solution would be to erect a second gantry (or
even just a transmission tower) say 100 meters down the road from the
first one: it would be much simpler as it doesn't have to video each
car, just transmit a signal back to the e-Tag.  100 meters is about
3.5 sec at 100km/h (100x1000/60/60 = 27.7m/sec), more than enough time
if I use your figures of 2-3 seconds.  

Even if each extra gantry cost $1 million, you'd have to think it
worth it to them to construct them so that they can start collecting
tolls and avoid the huge cash flow drain they must be experiencing.

       
Regards

Yuri
-- 
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Yuri J Sos
Melbourne VIC AUS

Reply to: steam4me@enternet.com.au

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