DOD vs. 802.11b

goombah99 writes "The NY times (reg required) reports that "The Defense Department, arguing that an increasingly popular form of wireless Internet access could interfere with military radar, is seeking new limits on the technology". It would seem they have a good point; radar is an essential for both defense and civilian aviation as well as ship navigation in tight quarters. Critics of the restrictions contend technology can limit the interference, but what proof is there to these assertions? Sure we all want wireless internet but maybe there should be more careful review of its consequences."

Comments

Re:FCC should take care of this

[Albinoman]

I was going to reply to this in your way. This is absolutely right. Isnt the FCC supposed to check what frequencies are being used by what and allocate wavelengths accordingly? Why hasnt the NTSC complained (different frequecy radars I might guess), they are the one who actually need radar over our soil. What the heck are the military tracking other than training flights?

Re:Typical Military BS

[shylock0]

Yeah, but I think the broader point is that it "might" cause interference; nobody knows, and the military just wants to put things on hold to test things out. Note that they talked not just about tracking systems, but also about possible interference with missile guidance. The people over at the DOD who work on these things all have PhDs in physics, so I'm assuming this isn't all BS.

It would be a real, real shame if wireless tech interfered with long-range weapons systems so that, say, wireless tech in Israel caused enough interference for smart bombs in Iraq to hit a hospital instead of a weapons depot... I'm not saying its possible, I'm just saying that the possibility needs to be investigated, so that the military can redesign their systems to fix the problem.

Won't someone think about the Whales?

[Flamesplash]

Apparantly this only works one way. There have been a lot of articles out lately about Navy sonar and other artificially generated waves interfering with Whale communications.

I wonder what they would do if the Whales went and destroyed facilities developing the devices that mess with them. Now if only they could get them to do the main development on ships, then the time of the Whale will come upon us. MWUAHAHAHAHA

This is about 5Ghz technology

[goombah99]

Despite the misleading headline inserted by slashdot editors, the article refers to an"increasingly popular" wireless technology in the 5Ghz band.

The pentagon is not trying to poop on the wifi party. And they are not out to supress info transfers. They just want to make sure that a stupid irrversible giveaway of the wrong band does not take place. Apparently a lot of next generation radars need this band and depend upon a noise free environement. for example the article notes weather radar. Believe me getting a radar return of gas is very very difficult. Even high power radars are not the whole answer--the return signals are weak and fall off 1/r^2 limiting the range.

My fear is that the bush admin will give way to the coroprate interests. Microsoft is one of them mentioned in the article. these companies have dumped tons of money into campaign contributions. And the easy thing for the bush admin to do is to do nothing at all.

regardless of your misgivings about the department of defenses other activities, having good radar is a swell idea that we all can benenefit from.

presumably there might be some techno fix that could make all happy. But remember these radar systems take years to design. Its not just about making the latest up-to-date technology but also about quality assurance, standards and interoperability. So just saying they could be redesigned is not a valid response. You dont retrofit safety systems on a whim because some thinks they can make it better. Murphy's law will get you. And its often better to have standardized less than state of the art systems people know the limitiations of than a myriad of superior technologies they dont know the relaibaility of.

Re:This is about 5Ghz technology

[archeopterix]

Shouldn't it show the DoD that they should start work, today, on the next-next generation of radar, which won't be able to be foiled by a bunch of high-power 5 ghz transmission devices, the basic parts for which might soon become available from civilian outlets over the Internet.

It's not that easy to jam a radar. Bats are a living proof of this. Thousands of them can navigate in dark caves without jamming each other. Radars are designed to avoid jamming - they use quite a wide spectrum of radio waves that changes dynamically (bats do that too, only with sound waves). Of course it is probably possible to build a jamming system, but such a system would involve many high-powered transmitters and thus would be very costly. I guess that widespread use of radar-frequency Wi-Fi would just slightly degrade military radar performance (perhaps civilian aviation radars would suffer more) and that's what the military are concerned about. I would be more concerned about a kilowatt radar signal damaging Wi-Fi equipment though.

Re:Other problems as well

[aborchers]

Interference of cell phones with avionics is a red herring. The real problem with using cell phones on airplanes is that at high altitude and speed, a cell phone hops towers too frequently.

The case for avionics interference is actually quite weak, from all reports I've heard. The policy for cell use on aircraft is partly CYA, partly greed (use our in-flight phone instead) and partly a cookie to the cell industry, which cannot or does not want to deal with the hassles of supporting high-speed tower-hopping on their networks...

The wrong target?

[bald_spot]

According to This article, The most important source of interference in the band is commercial microwave ovens, of which there are over 100 million in use in the US alone.

Yeah riiiight

[phr2]

Free wifi is going to interfere with military radar, but I bet when some big-money corporate interest group wants those same frequencies, they will get them with no radar objections being raised. We don't hear about UHF television interfering with radar either, or 1.8 ghz cell phones, etc. This is just another scam on the goverment's part to interfere with private communications.

Re:fear mongering

[corebreech]

Fear mongering? No current examples of interference???

No current examples of interference are possible, since our military appears to be completely incompetent!

Consider 9/11. At approximately the same time the first airliner struck the World Trade Center, the flight that was to hit the Pentagon went NORDO, i.e., was identified as a hijacked aircraft. This thing was tracked on radar for FIFTY FUCKING MINUTES before crashing into THE FUCKING PENTAGON of all places and the fine men and women charged with protecting our airspace DID ABSOLUTELY NOTHING TO PREVENT IT!

It takes big balls on their part to now say that we can't do any further development on WiFi because it will impair the military use of radar. I fail to see how military radar can be rendered any more ineffective.

Re:802.11 and police radar

[Izang]

Jamming is a delicate science.

You can tell, by the tone, if a car is reflecting or emitting a signal. There are a few officers like to listen to the doppler shift and it's easy for them to tell if you're jamming. I should know, I was stopped in West Virginia for having one on my motorcycle. Small, low power but since I had access to a radar gun I knew that it kinda worked. I was lucky he couldn't find it wedged way down behind the faring.

The reflected signal off a car is extremely weak so it doesn't take much power to screw with radar. If you really want to have fun put a fish finder in your car and mount the transmitter/receiver on the grill. Something high powered like that will make a radar gun totally useless.

Yep, that's the obvious point.

[twitter]

Killing the utility of 802.11 in the US won't keep others from expoiting our problems. It will simply keep us from having better, lower cost communications. I posted this making fun of DoD in another thread.

Re:This is still about fighting "terrorists"

[Catbeller]

Osama bin Laden does not use beepers, landlines, telephones, cell phones, WiFi, the Internet, laser comm, satellite phones, carrier pigeons, or the U.S. mail.

He communicates via trusted lieutenants, face to face.

The idea of terrorists using the Internet and WiFi in particular is not only speculative, it's just plain wrong. A professional guerilla warrior does not use traceable tech, not if they want to succeed.

This is FUD. And a prelude to a marketing campaign against free networks. Or, it just illustrates the really bad thinking coming from the White House's Nixon retreads right now -- not Bush. Bush doesn't know WiFi from HiFi. This is coming from the army of Marching Morons that are running the Executive Branch and the DoD right now, to the dismay of the intelligent professionals who have been shoved aside and told to shut up.

Take it from a Navy Radar Operator...

[GeekZilla]

...there is more risk to the WiFi networks being jammed by military radar than the other way around. The newest radar's pump out hundreds to thousands to millions of watts of power depending on the type of radar and the platform. Plus, today's military radar's are frequency agile and extremely adaptable to interference and jamming. This appears to be just another attempt by the DOD/DOJ/Big Brother Government to control things that they feel are a threat to their control.

Re:SETI Concerns?

[1fitz2many]

I think all astronomers, not just SETI folk, are concerned about interference. Remember, these signals may not look like random noise.

Radio interference is a problem in astronomy that continues to grow. Astronomers consider the amount of interference as an important factor when choosing sites for new arrays, sometimes situating them in valleys to help mitigate these effects. Indeed, there are radio-quiet zones around major facilities, where (e.g.) cell-phone use is prohibited.

I'm sure some astronomers would be smirking at the military now getting concerned about interference problems (when the military generally didn't care about their systems interfering with astronomy), if it were not for the fact that these problems affect us all.

They're giving ideas to terrorists

[RickyRay]

By announcing to the whole world that they can't deal properly with ordinary WiFi, the military is encouraging terrorists to interfere in those frequency ranges. Which means terrorists and military regimes could buy cheap, off-the-shelf WiFi, amplify the signal to make sure it gets noticed (if it's strong enough it could even interfere), and scatter the transmitters all over the place to keep the military busy tracking down ghosts.

A friend of mine (just as an experiment; I wasn't involved) once tried driving down the road with a box that repeated speed detector signals back to cops with a slight frequency shift (to mimic the Doppler effect) and amplified (to block the correct signal). His speed was legal, but the cop started banging on the speed detector because it either said he was going really slow or insanely fast (exaggerated enough that it couldn't possibly be correct). Needless to say, you can't buy such a box legally ;-)

WI-FI is spread spectrum, radar is AM

[Anonymous Coward]

It is impossible for WI-FI to interfere with radar because of the simple fact that spread-spectrum modulation spreads the energy over a wide band and turns the signal into an extremely small amplitude wide-band energy that will not even be seen by a radar receiver looking for pulses in the time domain. Spread spectrum is in the code domain. WI-FI will not interfere with radar and radar will not interfere with WI-FI. The radar receiver's noise floor will be higher than any WI-FI spreaded signal. If the WI-FI adapter gets so close to the radar that it can interfere, it would have long since burned up from the Megawatt radiated pulses from the radar.
This is typical exagerated government BULL SHIT.

Re:802.11 and police radar

[Izang]

I'm just telling what I have seen. An 8000W fish finder, maybe 200khz, will totally screw a radar gun. My ex-brother-in-law was a cop and we've tested it right out of the boat.

How about UWB 802.11?

[JohnnyCannuk]

Sounds like a good time to switch to/invest in a new 802.11x ultra-wide-band solution.

UWB, as I understand it, sends out nano-second pulses over a wide band of frequencies. These pulses sound like regular "noise" if they are detectable at all. Best part they don't interfere with existing signals on any particular frequency. They can be used for communications or specialized radar (ground penetrating, seeing through walls to find people etc).

So either your DOD swithces it's radar or gets your FCc to allow higher power UWB (currently the range is limited to about 10 meters...great for a UWB mesh network ;) )

Anyway, I may not be the most knowledgable in the field, so someone ca correct me but this sounds like a great opportunity to make a better more decentralized technology take hold

How many times do I have to say this...?

[cr0sh]

I have read many of the comments made on this topice here in this forum. I understand that there seems to be a confusion as to whether this issue is related to 802.11a or 802.11b. Frankly, I don't think it matters.

The fact is, 802.11x communication systems ARE REGULATED BY THE FCC. If they chose (or were ordered), they could easily deem the spectrum used by 802.11x to be off-limits to anyone! Sure, I have heard the comments like "but businesses have invested millions in 802.11 - they would howl" - perhaps they might. Or perhaps a transition would occur to make the larger companies happy, by providing some form of wireless that isn't available to the average consumer like 802.11x is - but still gives those communications companies a foothold in wireless comms, while making consumers happy, and also possibly providing an easy place for the feds to tap, while making community nets a thing of the past (think it impossible? Try to buy, as a consumer, your own TXRX system for a cell phone - good luck, if you can even afford it). Everyone (mostly) wins - except for the citizen, ne - consumer...

I have said many times that the government has this (unelected, unrepresented) power via the FCC to do this (think I am joking? Do a search on my past comments, if you don't believe me). In these same comments, I have presented a solution that very few have worked on (at least on the homebrew front), that could keep community networks alive, a solution the government (FCC) cannot regulate (but oh how they would try - and if they succeeded, well - then that is the cue for true revolution):

Laser/LEDComm

I daresay RONJA is probably the most advanced "homebrew" system out there (if anyone has links to more advanced stuff - such as on the order of homebrew sighting/retargeting systems like AirFiber's System - please post links!). Other links of interest:

http://www.alphalink.com.au/~derekw/upn tcvr.htm

http://www.hut.fi/Misc/Electronics/circu its/laserlink.html

http://www.geocities.com/Silic onValley/Lakes/7156/laser.htm

http://www.n1bug.ne t/tech/laser/laserfr.html

http://www.n1bug.net/te ch/laser/alc_wa6ejo.html

http://www.repairfaq.org /sam/lasersam.htm

http://www.qsl.net/w1vlf/techin fo/optical_transmitters.html

http://misty.com/peo ple/don/laserdon.html

So - these systems have problems (line of sight being the largest) - but all systems have problems. At least one company (AirFiber) is using similar tech to run a business for WAN layouts - so it should be possible for a homebrew solution to be worked out. Are we going to simply wait until 802.11x really gets "outlawed" before we do something? What kind of shit is that?

Oh - wait - this is /. - where apathy seems to almost be the rule when it comes to politics...