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Comment by Animats | Hacker News Reader

That device is more useful for firefighters than for cops. Firefighters need to find people inside burning buildings. Looking for trapped people is one of the more dangerous jobs in firefighting. The fact that it's being sold more to cops than firefighters indicates that cops are getting too much money for tactical gear.

The device is a fairly basic Doppler radar, although the sensitivity is impressive. Someone might want to look up the FCC approval data for it to get the full technical specs.

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> Someone might want to look up the FCC approval data for it to get the full technical specs

Someone using a new account named throwawayranger did that and posted the results, but the comment was promptly killed because it was a new account posting via TOR.

For those without "showdead" enabled, here is the content of the dead post:

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L-3 Communications RANGE-R Operator's Manual http://blockyourid.com/~gbpprorg/mil/wall/RANGE-R-1.pdf

Internal Photos http://blockyourid.com/~gbpprorg/mil/wall/RANGE-R-2.pdf

External Photos http://blockyourid.com/~gbpprorg/mil/wall/RANGE-R-3.pdf

Test Report http://blockyourid.com/~gbpprorg/mil/wall/RANGE-R-5.pdf

Handheld Radar Frequency Scanner for Concealed Object Detection U.S. Patent 6,950,054 http://blockyourid.com/~gbpprorg/mil/wall/US6950054.pdf

It's a low power device (35mw), but it's in a radiolocation band, so they had to get a wavier from the FCC. That's an interesting read, because it lists the uses. They're getting surprisingly good range for only 35mw radar power.

https://apps.fcc.gov/edocs_public/attachmatch/DA-09-2482A1.p...

The patent is for a different device - that's for a better version of those wands used in security screening. The approach is similar, but the power is much lower.

To give an idea of just how whacked the priorities of the Police are, with the recent announcement from the Attorney General of the US that the Federal government would no longer cooperate with civil seizures of property unless a crime has committed our locals (Atlanta and Dekalb county) are now pushing the state to expand civil seizure laws.

This is for seizure of property without proof of a crime. They want it expanded because the money goes to them. If ever a law needed to be passed it is to revert the whole idea of civil seizure and the idea that any monies obtained by the police go to them, if at all money seized by police through tickets or any other means should go anywhere but them

US civil seizure laws make me incredibly thankful that I live elsewhere. Not just because these laws exist, but because they demonstrate how meaningless the US constitution really is in practice.

> That device is more useful for firefighters than for cops.

It's even more useful for burglars than for both cops and firefighters...

Reading the article, I thought this might be a UWB (Ultrawideband) device. But going through the tech specs, I'm not sure. It just might be, but it doesn't say in the specs.

"...of a stepped-frequency continuous wave (SFCW) radar transceiver...The RANGE-R cycles through a sequence of 120 frequencies in 2 MHz increments from 3.18 GHz to 3.42 GHz. At each of the frequencies, it transmits a maximum 32mW power level with no modulation."

UWB would work with 500 Mhz or more spectrum, here it's only 240 Mhz, but why not. And UWB would be a pulse-based system.

I thought that there were already UWB Radars deployed with firefighters. Can't find any right now.

If you're interested in UWB: (1) http://en.wikipedia.org/wiki/Ultra-wideband (2) http://whatis.techtarget.com/definition/ultra-wideband

Fire fighters often need to find people who are not breathing or otherwise moving.

would the huge increase in heat in such burning buildings hinder the usability of a Doppler radar? I would guess so, as different temperature should mean different speed of sound.

It is a radar device so the speed of sound is irrelevant. The speed of light in air (and hence the refractive index) does depend slightly on temperature / pressure, but not by very much: https://physics.stackexchange.com/questions/6872/refractive-...

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