Well bookm in response to your post.
Now let's say this is a 2 lane highway and you guys are the only 2 cars plus the officer.
In that case he would check the speed of both vehicles. Sure it may not " be vehicle specific: and he can not be 100 % sure its you but what he can do is check the speed of your vehicle (faster one) and the speed of the vehicle you are passing (slower one).
This would be possible with Genesis 2 or the Stalker i beleive. He can do this in motion. He could definitely get both vehicles speed by being directly behind them.
While this guys ticket was very un lucky and perhaps a not so nice officer he can definitely get that.
Now if this was a 3 lane highway with lots of traffic and he was on the side of the road that may be different.
But when they get you for speeding while they are moving that is always radar and they would have to be in front of behind of your car.
I am not 100 % sure but after reading lots upon radar/lidar in the past this seems to be.
Radar is not vehicle specific but i dont think it is like that. It sure as hell isnt as good as lidar where they target your car and get a exact reading.
Here is a youtube video of a office using a radar unit.
[youtube]http://www.youtube.com/watch?v=7V12C2n7M08[/youtube]
Watch when he is on the highway. If this is the case i put no faith into it.
Maybee where hwybear patrols in Chatam where it is only 2 lanes and light traffic.
But in and around toronto this is unfair.
I mean lets say you have a group of multiple cars on the road. They are all exceeding the speed limit and getting to close. This is common in the GTA. Youll have cars racing up 130-140 only to get stopped by someone slower in the left lane.
Now when the road is packed with all cars slowing down, speeding up, changing speeds, changing lanes how does a unit like this work?
I mean if you have a bunchof cars doing this how can he be sure at that exact time it was your vehicle going that speed. He might think you are faster cause you accelerated but the radar unit got the guy who has now speed up for example.
My post is a bit confusing on this unit but in some situations i dont get how this would work and the court would not have any argument to how it works.
This is not lidar. Secondly back the post topic from the sounds it was on a smaller 2 lane highway in an off peak time and the officer was behind them using on moving radar. He watched the whole thing and got the speed of the faster vehicle (guy who passed) and charged him with speeding.
From what i understand Radar can be moving (installed) and hand held. Lidar is always hand held.
It is my best guess if the officer is facing the same direction of traffic on the side of the road he is using one of those built in units. For lidar he is facing you. And if they feel like it they can drive and check your speed at the same time.
From what i understand a Radar/Lidar unit sends out small pulses of light or radio waves in the case of radar and it calculates the time it takes them to get back or the difference in the time it gets them to take back.
That is why with radar you can detect it and the officer can get info on the side of the road such as fastest vehicle for example. Although with lidar since it is sending out small pulses of light it has to be vehicle specific.
I find with lidar they are facing the front of your vehicle aiming the laser at your front plate. With radar in the GTA they always seem to hide under a bridge etc and face the same way you are and check your speed one you pass by them (radar i assume).
I am guessing with heavy traffic radar is the choice while in lighter traffic and off peak times laser is more useable?
I am not sure on all of this. There is another thread where hwybear responded to some of my questions about radar/lidar that was very good.
Although with most police officers it is my guess if they are not sure its you then they are not going to charge you with speeding. You need to remember they are trained to use these units and have experience, practice, and education using them.