Police radar being removed from cars...

[Ixion]

Radar detector ban has been shelved. For the moment at least. MoT say "the role of radar detectors will be considered as art of Road Strategy 2020" due for public comment around August.

[Patch]

guess I just painted my wheels in stealth paint for nothing then . . . oh well shit happens

[cowpatz]

It maybe those 400 cars are going to be used for other general duties (such as call outs) rather than road policing now.

No no.... they send taxi's not patrol cars

[jono035]

guess I just painted my wheels in stealth paint for nothing then . . . oh well shit happens

Stealth paint to prevent speed detection by radar? Yikes, who sold you on that one?

[CookMySock]

Steve: You'd be surprised how hard some of those things actually are to do. The main problem is that you've got a receiver in the cop car and a receiver in the target car. The sensitivities are the same so you have to do something that will allow enough signal to be reflected from the target car to be detected by the cop car, without the target car sensing it. All of that is governed by sphere law stuff, so basically it takes a heap at the target car to even be detectable back at the cop car. There are a lot of techniques that could be used to attempt to defeat this, but the thing is it is an inherently easy problem to solve on the detection end and a hard one on the speed measurement end.

I'd just make up a bunch of small solar panel+battery+high-freq oscillator and feedhorn units and scatter then all around the place... Raise the noise floor so high that you can't go for more than a couple of kms without your radar detector going off...

It would come down to processing power, I would say. Your cellular phone has a hundred times more CPU in it compared to your radar detector, and if the fuzz put 20-30 MIPs of CPU behind some microwave transciever, the results won't be pretty (for speedsters.)

If they DO go to smart radars, I will be interested to see the industry that it spawns. It could get quite high-tech, because modern radar detectors certainly aint.

Steve

[Dare]

It would come down to processing power, I would say. Your cellular phone has a hundred times more CPU in it compared to your radar detector, and if the fuzz put 20-30 MIPs of CPU behind some microwave transciever, the results won't be pretty (for speedsters.)

If they DO go to smart radars, I will be interested to see the industry that it spawns. It could get quite high-tech, because modern radar detectors certainly aint.

Steve

I expect R&D for something that high tech would be astronomical if it doesn't filter down through military use, who else needs handheld speed anti-detector detectors that badly? What are other countries using?

[jono035]

It would come down to processing power, I would say. Your cellular phone has a hundred times more CPU in it compared to your radar detector, and if the fuzz put 20-30 MIPs of CPU behind some microwave transciever, the results won't be pretty (for speedsters.)

If they DO go to smart radars, I will be interested to see the industry that it spawns. It could get quite high-tech, because modern radar detectors certainly aint.

Steve

From a signal processing point of view I don't think there is all that much they can do with further processing power. Ultimately the speed detectors still need to send some form of signal out and no matter how complicated you make that, the radar detectors don't need to be able to 'understand' the signal, they only have to figure out that there is a signal there!
Ultra-fast frequency hopping might confuse some detectors that are currently on the market but they wouldn't require much of a change to start picking it up again.
Like I mentioned before, it's a very asymmetric problem. The target car has higher signals strengths and only needs to detect that there is something there, it doesn't have to be able to tell anything else from the signal...

And 20-30 MIPS is peanuts these days with pipelining processors, a decent DSP will be up in the x000 MIPS (x GIPS) range! None of that will help though unless they can figure out a way to make their output signal undetectable by the target, which is a difficult one to be sure.

[jono035]

I expect R&D for something that high tech would be astronomical if it doesn't filter down through military use, who else needs handheld speed anti-detector detectors that badly? What are other countries using?

Almost every country in the western world uses some form of speed detection whether optical (camera + road markings), microwave or laser. I'd guess that it is an absolutely massive industry so if there is a demand, someone will develop it...

There were specific devices designed to detect whether or not the target had a radar detector in use in the US (worked by picking up trace signals from the radar detectors local oscillator). As a response some of the companies started making radar-detector-detector proof units with better shielding to prevent this. There has already been a couple of iterations of cat-and-mouse in this game, I imagine there will be many more

[YellowDog]

Yeah right!

Maybe the cops have found some real work to do................

[scumdog]

Yeah right!

Maybe the cops have found some real work to do................

And maybe they're splitting police into two grops.

Cops
and
Traffic Officers - who only do traffic stuff, just like they use to in the old days...

Or are they already doing this?

[CookMySock]

There were specific devices designed to detect whether or not the target had a radar detector in use in the US (worked by picking up trace signals from the radar detectors local oscillator). As a response some of the companies started making radar-detector-detector proof units with better shielding to prevent this. There has already been a couple of iterations of cat-and-mouse in this game, I imagine there will be many more

Actually, that local oscillator signal is quite massive. All they did was move the detectors LO elsewhere so the detector-detector couldn't find it. "cat and mouse" is all that is, and is certainly not any level of smartness.

Seriously, pointing a massive beam of microwave energy down the road and pulling tones out of its' mixer diode is the most ridiculously simple radar there is. If such a device was made in the 1950's it would have only one valve in it.

Steve

[Naki Rat]

I'll confirm this. they mostly drive around with them off. They have a little 'remote' type thing in one hand that they use to turn it on...which leads me to believe MOST radar detectors would be useless anyway...if its not on, it cant tell you their coming!!!

You usually can tell 'they're coming' because the HP tend to do spot checks on a regular enough basis to give you warnings from vehicles being 'checked' well ahead of you.

[CookMySock]

You usually can tell 'they're coming' because the HP tend to do spot checks on a regular enough basis to give you warnings from vehicles being 'checked' well ahead of you.

Surprisingly, I have never seen that, but I can see it would be a useable tactic.

Once I was in a group of cars travelling WELL below the 70k speedlimit and I got an instant and massive POP warning. Dunno what that was all about - other than that I've never seen a POP warning before, only Ka warnings.

Theres lots and lots in interesting vids on youtube. Search for "police radar".

Steve

[Ixion]

Actually, that local oscillator signal is quite massive. All they did was move the detectors LO elsewhere so the detector-detector couldn't find it. "cat and mouse" is all that is, and is certainly not any level of smartness.

Steve

Not quite. That was an early approach to dealing with the detector detector problem. But the snakes soon caught on to that , and extended their search frequencies.

But the latest Bel Sti (and others) do shield the signal completely.

[Swoop]

You usually can tell 'they're coming' because the HP tend to do spot checks on a regular enough basis to give you warnings from vehicles being 'checked' well ahead of you.

Quite true. Get a detector with a decent detection range and "instant on" will alert you enough to the presence of a tax collector.