Detecting snipers

johnniet

johnniet

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Because of the dangers of urban warfare, I was thinking the other day about ways that you might try to detect a sniper who you couldn't see.
Almost all sniper rifles have cylindrical metal barrels. If they are near a source of radio waves, they should emit a distinctive radio "hum" of their own.
Could you set up a radio source in a war zone and find a sniper based on the radio hum from his gun? Maybe even a sniper hiding in a building?
I looked this up on Google, and found one "page" about this:
www.rand.org/publications/MR/MR912/MR912.app.C.pdf
(If you can't read pdf's, look up "Resonance Weapons Detection" on Google and use "View as HTML").

Apparently they tried this during the Vietnam war. It often worked, but they had problems because they didn't have today's computers to do the signal processing.

Does anyone hear know more about the tests done during the Vietnam war?

Has anyone heard of a system like this being tried out today?

[Edited because I am a moron. I know that it should have been "anyone here". But this is the kind of mistake that should be preserved for posterity. :D]
 
There was something on the Discovery Channel once that featured technology to detect where shots were being fired from, but the system required that shots be fired first. The system would then show where the rounds were coming from onscreen. On a much larger scale, our military has the technology to track artillery rounds as they're fired to their source which can then be taken out precisely with our own artillery.
 
If the theory works, then everything made of metal within the vector of sound would resonate (sp?), as well.

As to rifle barrels, it's more likely to happen to thinner barrels, like those on mountain rifles. If it is detected during a shot it's because a barrel 'whips' like someone snapping a jump-rope and watching the arc walk down to the end.

Real sniper barrels (and those on varmint rifles) are short and stocky. The stiffness makes sure the barrel stays bedded to the most accurate placement. Such a barrel won't move that much.
 
I'm not talking about a sound resonance, I'm talking about electromagnetic resonance. The "humming" metaphor is just to remind you of how much resonance you can get at the right frequency, like humming in an elevator.
 
Guys, I read the article and actually did some prelim. calculations with model equations. First, the ground based system is assuming a 10 square METER antenna. That's aweful big to put up in the field. Next for DETECTION on the ground (not discrimination, where exactly it's at) you're looking at a useful range of 3.7 kms. or 2.3 miles. Now, if a sniper is taking some shots at you, don't you think he's gonna see a 10 square meter antenna? Add to this the problem of the very narrow range of individual frequency resonation for different rifles, and the fact that this device, at least on the ground is "line of sight"(it can't look through hills). I would venture to say that it's not a very practical methodology. Spoofing the thing would be easy, all you need to do is set up various dummy barrels within the proximity of the kill zone for the shooter. Technologically feasible, sure. Practical....not yet!:D
 
Marcangel,
thanks for trying the calculations. I hadn't worked out the details myself. :o
So far, I am a bit more optimistic about the usefulness of this system in some environments.

Originally posted by marcangel
Guys, I read the article and actually did some prelim. calculations with model equations. First, the ground based system is assuming a 10 square METER antenna. That's aweful big to put up in the field. Next for DETECTION on the ground (not discrimination, where exactly it's at) you're looking at a useful range of 3.7 kms. or 2.3 miles. Now, if a sniper is taking some shots at you, don't you think he's gonna see a 10 square meter antenna?
Click to expand...

What if the radar source is on a plane, helicopter, or UAV?
What's the sniper going to do about it, anyway? Any action he takes to stop you or avoid detection will tend to expose him or reduce his effectiveness.

Add to this the problem of the very narrow range of individual frequency resonation for different rifles, and the fact that this device, at least on the ground is "line of sight"(it can't look through hills). I would venture to say that it's not a very practical methodology. Spoofing the thing would be easy, all you need to do is set up various dummy barrels within the proximity of the kill zone for the shooter. Technologically feasible, sure. Practical....not yet!:D
Click to expand...

It can't look through hills, but it can look through foliage and (some) walls.
Yes, dummy barrels are easy to set out. It needs a way of detecting motion (this is probably not hard and is suggested in the article). Best would be a way of detecting a likely human presence in combination. There are other web articles about detecting people through walls, etc. but I don't know how far along the technology is.
 
the radar source might be big/powerful and very mobile, but the detector will still have to be the same size
unless you're thinking of carrying the 10m2 antenna along with it, it's not likely to work the way it should

the first thing i thought of was the operational considerations
it's a good idea, but until they can minimise the detector (2.3 miles is VERY good for sniper detection, too good in fact, when all we need is about 1 mile or so) for tactical usage + carry as well as fix a radar source, this won't see use in the field

also, what about background noise for OTHER cylindrical metal objects? that's also another factor which could interfere with the readings

generally, i like it though
 
Well, if I saw an antenna that big I'd say "Self, it's time we make like good little sheep and get the flock outta here!" Now, let's assume it's airborne, and you've got a much larger area you can cover. Said sniper places "dummy barrels" all over the place and ditches his own. Now, you've got an unidentified larger force threat that needs to be eliminated before the good guys can advance into the field. This is not good. One thing that we're not talking about is the advancements in FLIR which pretty much make this a useless idea. FLIR looks through vegetation, doesn't need ambient light and provides real time imaging. Those gizmos are ALREADY a little larger than binoculars and can even be bought on the commercial market.:p
 
We haven't discussed one issue here; isn't it the policy of a good sniper or scout to 'stick and move'?

If it was me, it would be 'one shot, one kill, one fast departure.'
 
That was my point all along. If you're under sniper fire, and start erecting a huge antenna, I'd like to believe a competent shooter would see that. If it's a one time target, well the game would be over before you could get a zero. Even though it's neat technology, (I know, I look at dem purty picters, darn near every day), it's not really a practical modality for imaging an individual man with a rifle on a mission....;) . Works really well for lookin' at your innards though...;) :D
 
Originally posted by marcangel
If you're under sniper fire, and start erecting a huge antenna
Click to expand...

i believe the point of this invention is to find the sniper BEFORE you get shot :)

btw, FLIR is thermal, right?
 
Forward Looking Infrared , or FLIR is a thermal imaging technique, yes. They're the things that look like a giant "eyeball in a pod". Every branch of the services and all most all state police agencies are using them.;)
Regarding deployment of the theoretical MR sniper detector, what are you going to do? Drive around on the ground with a 10 square meter antenna sticking out from the roof of a Hummer and the call in a fire mission every 2.3 miles when the box bleeps? Or are you going to have realize the threat first, and then deploy countermeasures? Something like this might work for protecting a high value target in a crowded area (like the President at a ballgame), where infrared imaging would be pretty useless because of the number of people in a small area, but I can't see much value in a system like this on the battlefield today.
 
Never saw the movie. I think that was also the title of the autobiography of Gary Gilmore's brother, Mikal (sp?)

I wonder what would have been the best way to smoke out those Serbian snipers. (Besides attack helicopters.)

How much do you have to aim FLIR before you can find the person?
 
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