Britain Could Switch Off Airport Radar and Release 5G Spectrum

judgecorp writes "Britain is considering switching off air traffic control radar systems and using "passive radar" instead. A two year feasibility study will consider using a network of ground stations which monitor broadcast TV signals and measure echoes from aircraft to determine their location and velocity. The system is not a new idea — early radar experiments used BBC shortwave transmitters as a signal source before antenna technology produced a transceiver suitable for radar — but could now be better than conventional radar thanks to new antenna designs and signal processing techniques. It will also save money and energy by eliminating transmitters — and release spectrum for 5G services."

Comments

Good idea

[Joce640k]

It works for detecting stealth fighters over Iran, it should certainly work for non-stealth commercial aircraft.

Re:Good idea

[Chrisq]

The real reason they're doing this is to test the new Ubuntu £inux phones. Those phones have experimental GPS tracking ribbons that transmit your location to the NSA from anywhere in the world along with a list of all the files on your phone. These are the same tracking ribbons used in 20 dollar bills. They have internal power supplies that are as thin as, well, paper, and are based on dark projects. Ubuntu phone is the next step.

Wow they have a great plan .... just wait for the 100% take up of Ubuntu phone and ... oh wait!

Re:Good idea

[Chrisq]

The stealth fighter is not really stealthy, we know about it otherwise if it was truely stealth we wouldnt even know it exists.

Then again it can be picked up by weather radar also. Its a huge failure.

Perhaps the current stealth fighters are just cover technology for the real ... wait a minute someone's knocking at the door

Re:Good idea

[Annirak]

That depends on the goal of the stealth tech. On the one hand, a fighter that you can't detect at all is helpful, but there are other goals for stealth tech. For example, it's awfully helpful to have an aircraft that can't be tracked by targeting radar. Not having to worry about RADAR-based SAMs or AAMs is really nice.

Weather RADAR tracking of stealth fighters is great for knowing that one is inside your borders, but not so good for providing targeting to anti-air systems.

Re:Good idea

[rossdee]

The Stealth Fighter (F117) is getting to be fairly old technology these days - after all it has been in operational use for over 23 years.

Re:Good idea

[Anonymous Coward]

The F-117 is no longer in active duty.

Re:Good idea

[GodfatherofSoul]

The stealth fighter is ancient technology. The faceted sides are because no on had the processing power to calculate radar signatures for rounded surfaces. The stealth generations as I recall:

1st: cruise missiles
2nd: B-1 Lancer
3rd: F-117
4th: B-2 stealth bomber
5th: F-22 Raptor

Re:Good idea

[EdZ]

You recall somewhat incorrectly. The F-117 was designed with radar and IR stealth in mind, but limitations in simulation (both computerised and by hand) at the time lead to it's faceted design. The B-2 was similarly designed, but with the aid of computer modelling to allow curves, making it more aerodynamic. The F-22 was designed to be stealthy, reducing radar cross-section through use of surface materials, internal bays and inlet design, but the overriding design criteria were for performance, not stealth. Thus, the B-2 (a huge plane) has a smaller radar cross-section than the physically smaller F-22. It is a similar case for the F-35, except it was designed for forward-aspect stealth, at the expense of all-aspect stealth (i.e. you may not see it coming, but there's a good chance you'd see it going if you were still around).

Then there aircraft with 'accidental' stealth, like the old YB-49 to which the B-2 bears a startling resemblance. There's a may-or-may-not-be-apocryphal story that Jack Northrop, designer of the XB-35/YB-49 (among other flying wings) was shown a model of the B-2, a black project at the time, on his death-bed, due to the contributions he made to the design of the flying wing.

What Could Possibly Go Wrong?

[Penguinshit]

seriously...

Re:What Could Possibly Go Wrong?

[Anonymous Coward]

People could feel that 4g is fast enough and have absolutely zero interest in upgrading, thus robbing the UK government of over inflated profits at auction, then again, it has a higher number, consumers will happily buy in.

Re:What Could Possibly Go Wrong?

[shri]

What could go wrong? In 10 years wireless transmitters may be deemed unnecessary as a major sources of entertainment are being delivered via IP or via DISH type satellite systems. Can someone draw a graph of how many shortwave receivers will be used v/s how much IP bandwidth major providers will be using?

Re:What Could Possibly Go Wrong?

[Anonymous Coward]

BA 5390 didn't need radar to guide it down. No maps got sucked out.

Re:What Could Possibly Go Wrong?

[AHuxley]

http://www.bbc.co.uk/dna/place-london/A20460782
"but due to the congested airspace around both Gatwick and Heathrow, he was directed to land at Southampton Airport. Southampton was closer, but all the maps and charts had been lost in the blow-out, and having never landed there before, the co-pilot was obviously anxious about the prospect of making a good landing."
http://www.fss.aero/accident-reports/dvdfiles/GB/1990-06-10-UK.pdf
"The co-pilot had requested radar vectors to the nearest airport and had been turned towards Southampton Airportand eventually transferred to their approach frequency."
"I have a VOR but it will be radar vectors onto the visual final"

Re:What Could Possibly Go Wrong?

[Penguinshit]

Not quite sure what your point is. Mine is that airport radar is critical safety equipment that I don't want compromised so some teen can stream One Direction in HD.

Re:What Could Possibly Go Wrong?

[gigaherz]

I don't think satellite-based entertainment will ever really grow much, as it's not interactive enough, or at least too laggy. TV over IP over optical fiber makes much more sense to reach the houses, and terrestrial wireless for mobile devices. Question then is how much of that content will be consumed from the mobile devices.

Re:What Could Possibly Go Wrong?

[oji-sama]

Umm. Radar vectors are basically directions for the aircraft, I don't see why you couldn't give vectors for the aircraft if you get the same information from a passive radar. (Also, the planes will most likely keep their radars, won't they?)

Re:What Could Possibly Go Wrong?

[shri]

What I was implying rather hastily was that these transmitters might not exist when they're ready to make the switch.

Re:What Could Possibly Go Wrong?

[deimtee]

It's too laggy if you use geostationary satellites. 36000km each way is too far.
I have read articles that claim you could run a swarm of LEO satellites at 500 - 800 km high that talk to each other with lasers, and the ground with microwaves.
Basically a mesh network in space. In remote areas you would beat wired speeds.
Of course you need a lot of satellites for coverage, and a microwave transceiver for each connection to the swarm-net.
Everything needs to know where everything else is (to point the lasers and antennas), so I think the ground stations would have to be stationary, at least in the beginning.

Re:What Could Possibly Go Wrong?

[cheesybagel]

AFAIK most civilian aircraft have no radars whatsoever.

Re:What Could Possibly Go Wrong?

[Penguinshit]

ah yes, that is possible. But cell companies will try to squeeze every last drop from their infrastructure so it will be many years before they go away.

Re:What Could Possibly Go Wrong?

[prefect42]

They can have weather radar along with a radar altimeter, but I think you're right that they don't have radar for detecting nearby aircraft.

Re:What Could Possibly Go Wrong?

[serviscope_minor]

Civillian aircraft have all sorts of radar: airliners can detect other aircraft. I believe there was an incident where an airliner's collision detection radar atually detected an F117 and had to temporarily abort a climb, due to a near miss.

But yes, most civillian aircraft are small don't have any radar whatsoever.

Re:What Could Possibly Go Wrong?

[Capt.Albatross]

Airliners can detect other aircraft. I believe there was an incident where an airliner's collision detection radar atually detected an F117 and had to temporarily abort a climb, due to a near miss.

The Traffic Collision Avoidance System uses transponders of a particular type: they communicate with one another to determine mutual range (from round-trip signal times), azimuth (by using directional antennas) and altitude (as reported by the transponders). TCAS is mandatory for all but small airliners in most of the world, and the military use it when they are not in combat.

http://www.ll.mit.edu/publications/journal/pdf/vol02_no3/2.3.7.TCAS.pdf

Re:What Could Possibly Go Wrong?

[sunderland56]

First thing that could go wrong is a power cut. A traditional radar system can easily be run on a backup generator.

A power outage in Guildford shouldn't cause flight delays (or worse) at Heathrow.

Re:What Could Possibly Go Wrong?

[lattyware]

Do you have any reason to believe this will compromise security? The story implies the alternative is better.

Re:What Could Possibly Go Wrong?

[Alioth]

Well, firstly, since there are lots of transmitters, the loss of one in Guildford isn't going to shut the entire passive radar system down.

Secondly, no one is talking about removing SSR (secondary surveillance radar) which is based off actively interrogating transponders fitted to the aircraft. Indeed, the CAA is forcing everyone to move to (very expensive) Mode-S SSR transponders, a technology that's really already obsolete.

Re:What Could Possibly Go Wrong?

[tehcyder]

Most of the UK doesn't even have 4g yet, and they're already worrying about 5g?

Re:What Could Possibly Go Wrong?

[tehcyder]

Not quite sure what your point is. Mine is that airport radar is critical safety equipment that I don't want compromised so some teen can stream One Direction in HD.

Typical oldster, hey! leave us kids alone! no sense of fun yourselves, so you just don't want us to enjoy ourselves, it's not even fair, I'm going to marry Harry when I grow up, no one understands me...

Re:What Could Possibly Go Wrong?

[jjsimp]

A cable subscriber sees the end of the super bowl ~5 seconds earlier than a Satellite subscriber (That's all I got). DirecTV works just fine at my house. For internet surfing if it was faster and cheaper would be fine, it's the VOIP and online gaming that have a problem with Satellite.

Re:What Could Possibly Go Wrong?

[jjsimp]

And Facetime\Video Chat of course has problems with Satty.

Great Idea!

[Roger W Moore]

Now when there is a fault at the transmission mast which interrupts your TV signal you'll no longer be stuck watching a blank screen: just go outside and look for planes colliding.

Re:Great Idea!

[gadget junkie]

Because the transponders on the planes on 9/11 in the US didn't get turned off. Who needs to track airplanes that don't identify themselves anyways? They might be able to track those drones flying over your country spying on the people.

the radar equivalent surface of a drone is a very small fraction of the radar cross section of a general aviation aircraft. moreover, most if not all the radar available are 2D, which means they do not provide the altitude of the target. that's one of the original reason for the use of transponders in general aviation: even if a Radar got an echo off an aircraft, it did not provide the altitude data, and so it would not serve to enforce vertical separation.

The main weakness of a "passive only" approach is that it provides with a single point of failure, i.e. the ability of the system managers of GPS, Galileo and Glonass to degrade the accuracy of the signal. radars instead could overlap. if you simply cut and paste a naval frigate system of the 90s, it usually had a 2D Radar and a 3D Radar. the only caveat is that the liberal upper crust would look askance at somebody microwave frying his pancakes from two miles away.

Re:Great Idea!

[Roger W Moore]

I bet they have really good backups because they are critical systems on which people's lives depend. I doubt the same can be said for TV transmission towers.

Already at 5G?

[T-Bone-T]

What is 5G? We've barely started rolling out 4G!

Re:Already at 5G?

[Anonymous Coward]

Seriously... You've not heard of 5G? It's a whole G better than that dowdy old 4G. Better start saving up for it today!

Re:Already at 5G?

[arekin]

What is 5G? We've barely started rolling out 4G!

Let this short instructional film explain (it really explains nothing btw). http://www.youtube.com/watch?v=txjqV6eKabs

Re:Already at 5G?

[dkf]

Fie on thy archaic five gee, we have forsooth already commenced work on six AND seven gee devices!

I think we're going to have to work on the name though; 7G sounds too boring. I propose "G-Whizz" to indicate its immense speed...

Re:Already at 5G?

[umghhh]

A bit confused here (I suppose should be going out more often) is yoctobyte bigger then moronbyte - how do both relate to library of congress?

Re:Already at 5G?

[plaukas pyragely]

I bet by the time those new passive radars are rolled out to production you will know 5G very well.

Re:Already at 5G?

[Anonymous Coward]

Well, yocto is an official SI prefix, meaning 10^(-24). So you need 1 000 000 000 000 000 000 000 000 yoctobytes to store just one byte.

Now to store the complete internet in several yoctobytes, you must have an extremely good compression algorithm. :-)

Re:Already at 5G?

[RaceProUK]

I just got an image of one of these doing 150mph...

Re:Already at 5G?

[dave024]

It seems like some people just wanna call it 3G forever. Some of us like simple things with a number that increases every 5-15 years.

Re:Already at 5G?

[Sockatume]

Not even remotely accurate. 1G to 2G was a transition from analogue to digital cellular. You still only had a basic WAP modem function at best, and were charged per minute. At this point I had 56kbps dial up at home.

It wasn't until GPRS was added to that we even had a dedicated data channel and that was limited to sub-dial-up speeds, on a good day, but at least you were charged for the data you used and not how long your phone was online, so you could have an always-active data connection. At this point I had 512kbps broadband.

3G took that up to about 300kbps at launch - at least a tenfold improvement - and went as high as 2Mbps, before the arrival of HSDPA and related technologies that can get you up to about 50Mbps on the same spectrum. My phone was now as fast as - and often faster than - my home broadband.

1G - 0
2G - 0.05 - 0.1
3G - 0.5 - 50
4G - 50 - ?

Doesn't look like decreasing returns to me.

Re:Already at 5G?

[MightyYar]

Your math doesn't work out:
(2-1)/1 = 100%
(3-2)/2 = 50%
(4-3)/3 = 33%
(5-4)/4 = 25%

What they need to do is start over with an "H" instead of a "G". Sure, they'll initially take a speed hit as they go from 5 back to 1 - but then the increases will get back to a really big level:
(H1-G5)/G5 = -80%
(H2-H1)/H1 = 100%

Just come out with H1 and H2 at the same time. See, hire me!

Re:Already at 5G?

[Sockatume]

I am an imbecile.

Re:Already at 5G?

[rossdee]

But how many G will the passengers in the plane feel when they whack into the ground at 300 mph

Re:Already at 5G?

[tehcyder]

My G goes up to eleven.

Re:Already at 5G?

[tehcyder]

I don't know where you live, but in the UK 3G is nowhere close to normal broadband speed (2Mbps if you're not in a city provided with fibre or something), and 4g is about 8-10 Mbps max, average about 2 or 3 Mbps last I checked.

Re:Already at 5G?

[tehcyder]

I've just found out that if you show a 3D film and throw water at the audience, it now counts as 4D.

Truly, we live in an age of wonders.

Re:Already at 5G?

[X0563511]

I invite you to go learn how 4G works, and come back and tell us the results.

By no fault on your part, you will probably not understand what the hell is going on.

Re:Already at 5G?

[MightyYar]

It's easy, each G is faster than the prior G. The only question is, are H's even faster than G's? Do you work for the phone company? Can I have a job there?

Re:Already at 5G?

[MightyYar]

I apologize for my completely useless posts, devoid of all content. :)

Re:Already at 5G?

[yurtinus]

Depends on where they're from. Americans will experience significantly less Gs they have a much greater distance between the front of their lardass bellies to the back of their lardass asses to decelerate over.

Re:Already at 5G?

[X0563511]

It's not so easy.

If you want something specific to puzzle over, try reading about QAM.

Re:Already at 5G?

[MightyYar]

All joking aside, if T-Mobile can go from 3 to 4 without really changing anything, then my theory isn't very funny. If it was ever funny.

Infomercial Airlines

[EETech1]

So the safety of air traffic will rely on infomercials being on all night? Sounds like something the FCC will jump in on too!

The following is a paid advertisement, the views expressed are not the views of the network, we are however required by law to broadcast them to ensure the safety of air traffic throughout the evening. Please stay tuned for this important safety related broadcast.

Re:Infomercial Airlines

[Alioth]

To everyone thinking that safety will depend on the TV transmitters being always on, this is likely to replace only *one* of the types of radar, primary radar (where you send out a signal and look for reflections). SSR (secondary surveillance radar) won't be going away. This type of radar sends out a signal and the aircraft actively replies.

Primary radar is used to paint targets that don't have transponders. What the CAA has been angling to do for a while now is make Mode-S transponders mandatory in controlled airspace (they did want everything, including hang gliders(!) to carry a Mode-S transponder at one point). Therefore the cost will just be transferred to the hand-to-mouth sector of aviation if they want to still have access to controlled airspace.

Re:Infomercial Airlines

[LoadWB]

This addresses part of my question below. Thank you.

Re:Infomercial Airlines

[SuricouRaven]

I understand hangglider users are rather annoyed at this: Those transponders are designed for extreme reliability and durability, and as such they are of considerable weight. Enough to seriously impair performance on such a small and lightweight glider.

Re:Infomercial Airlines

[Sulphur]

I understand hangglider users are rather annoyed at this: Those transponders are designed for extreme reliability and durability, and as such they are of considerable weight. Enough to seriously impair performance on such a small and lightweight glider.

Corner reflectors and tinfoil hats come to the rescue.

Re:UK and TV rader? LOL

[Anonymous Coward]

I can vouch for that, I've never seen so many flying buses as that time I visited London.

Ten years away

[MichaelSmith]

Radar provider Thales has been given government funding by the Technology Strategy Board to investigate how existing TV signals could be used to locate and track aircraft

Thales are just starting out on this. An industrialised solution is therefore a decade away from availability and another ten years from being accepted as a primary source of data on aircraft movements.

Re:Ten years away

[Joce640k]

Radar is already secondary. Most information these days comes from GPS transponders on the aircraft, not radar. It's plotted on a radar screen but that's not where the info came from.

Re:Ten years away

[MichaelSmith]

Primary surveillance works by reflection. Secondary surveillance works with transponders. Here in Australia secondary surveillance radars are being shut down to be replaced with ADS-B but primary radars are being upgraded.

Re:Ten years away

[Sockatume]

That sounds about right for something that's meant to complement 5G cellular adoption, then.

A lot of signals ....

[Anonymous Coward]

What do you see if you take a closer look into the VHF signals arround there?

That's a 50Mhz TV transmiter carrier.

http://farm9.staticflickr.com/8383/8473254438_2a2f9819d2_o.jpg

A lot of aircraft reflections everywhere. ;)

Sould be "easy" to implement a multistatic radar with gnuradio.

73 de EA1FAQ

Re:A lot of signals ....

[Gordonjcp]

Wish you'd posted that logged in so you could get the karma.

Aircraft scatter on the microwave bands is good fun, with paths from Scotland into Norway and even as far south as Denmark. For those who haven't come across it, this is pretty much what the name suggests - point your aerial up and out over the sea when there are aircraft in roughly the right place, and listen for other stations doing the same and being reflected back off the aircraft fuselage. Because the signal is so tiny (a plane isn't that big, really) you need to use Morse code or one of the small-signal digital modes.

FB QSO YR 599 OM
73s de MM0YEQ

Re:UK and TV rader? LOL

[Pax681]

Yeah given the fact the UK has had only 4 TV channels for decades, took another decade to add a 5th channel, and reception is piss poor unless you live under an antenna.

And UK is one of the bussiest airspaces in the world.

I do not like this one bit.

um.. we have about 50 channels or so on broadcast TV now and countless bullshit channels factoring in satellite and cable
i get a better reception on the digital channels than i did on the analogue set up... not that i watch it much tbh... it's 99% shit which is generally what happens with hundreds of channels... that and fucking repeats

Government control of private transmitters?

[LoadWB]

Are all TV transmitters in England government-run? The problem I see arising from this plan is privately-operated TV stations become a critical infrastructure and eventually fall under government control for integrity and safety purposes. If a TV transmitter shuts down for whatever reason, planned or other-wise, then that part of the air traffic system could fail or operate under reduced capacity. If required for air traffic control, would TV stations then become "too important to fail?"

*sigh* Guess I have to go RTFA.

Re:Government control of private transmitters?

[sa1lnr]

All of the BBC's transmitters were sold off to a private company years ago as part of the Broadcasting Act 1990.

Re:Government control of private transmitters?

[Joce640k]

Airport radar systems can fail, too.

Maybe you'd better call them and express your concerns...

Re:Government control of private transmitters?

[Anonymous Coward]

The BBC's transmitters were originally owned/run by the BBC, but were spun off into a separate company and sold off, through various mergeres/aquisitions etc, that company is now Arqiva.

It's worth it.

[blind biker]

People need to share HD videos of their shitty cats with their Facebook friends.

Re:It's worth it.

[serviscope_minor]

Oh come on, it's not just cat videos, people need to be able to share smug self-superior posts on slashdot, too.

Re:It's worth it.

[dbIII]

They shouldn't need wireless spectrum for that job.
Cat5 cable is purpose built for the task.

If that's not enough the natural solution is to log onto the net with cat5e for 2.7 times more bandwidth.

Re:It's worth it.

[blind biker]

Offended much?

Re:It's worth it.

[serviscope_minor]

No. You have to try harder than that.

Re:UK and TV rader? LOL

[Joce640k]

um.. we have about 50 channels or so on broadcast TV now and countless bullshit channels

And program quality has dropped down to Anerican levels, yes. The relationbetween program quality and number of channels has again been proven to be inversely proportional.

Worse, the BBC is now in a deep financial crisis from having to fill up multiple channels instead of just two, quality ones.

Re:UK and TV rader? LOL

[Sockatume]

I'm not entirely sure what your point is supposed to be. Are you under the impression that there is insufficient TV broadcast intensity for passive radar to work?

Re:UK and TV rader? LOL

[ciderbrew]

I watch none of them.
iplayer for BBC content is about all. They have the news on in the lunch room so I've some idea of the 24hour repeat news world.

TV content people - I'm out.

Re:UK and TV rader? LOL

[Pax681]

um... again i live in a wee bit of a Valley next to Holyrood Park in Edinburgh.. the Salisbury Crags and Arthurs seat used to bugger the reception... not any more.
All those channels, as i said are shit, not that the originals were generally much better to be frank and under 10 of them on terrestrial are +1 channels
i only mentioned satellite in respect of channel numbers and not in reference to this technique for radar
Also the digital switchover finished last year i believe
as for quality.. it's all just shit really.... repeats are endemic due to the rolling 3 hour/4 hour block schedules many of those channels keep.. just shite.. however the TV is for the kids so.. meh, can't complain as i rarely watch these days
As for the BBC it's about to be in deeper financial crisis when it has to pay out over the various scandals including covering up institutional paedophilia with regards to Jimmy Savile and friends, fuck knows they get enough in from the license fees at £140 a year the conning bastards.. the only decent things about the BBC is no adverts as their coverage of Scottish issues is pretty fucking dire at the best of times but leading up to the Scottish Independence referendum they have openly stated they don't have to be balanced in reporting the independence debate which kinda fucks with their alleged reputation for impartiality.. so erm.. fuck the BBC really

Re:UK and TV rader? LOL

[isorox]

um.. we have about 50 channels or so on broadcast TV now and countless bullshit channels

And program quality has dropped down to Anerican levels, yes. The relationbetween program quality and number of channels has again been proven to be inversely proportional.

Worse, the BBC is now in a deep financial crisis from having to fill up multiple channels instead of just two, quality ones.

Not really. TV wise, the BBC funds BBC1, BBC2, and News Channel. BBC3, BBC4, CBBC, Cbeebies are part time channels occupying 2 full time slots.

Radio wise, digitial has added Radio 6, 1Extra, 4Extra and Asian Network. All of which are fairly cheap (I think the budget for the 1 extra is less than the budget for radio1's breakfast show)

There's also BBC World, which is supposed to be fully funded, however shares a lot of infrastructure with News Channel and national news. On the flip side, the advertising brings in money to invest in proper BBC.

Much of the new content on digital are repeats at a more convienent time. Childrens TV has moved from BBC1 afternoons to CBBC, and BBC1 mornings to cbeebies, and is now repeated.

The BBC has a financial problem because
* The license fee has been frozen for some years, with inflation meaning it's gone down in real terms
* The BBC had to fund part of the digital switchover
* Most recently (from next year), the World Service and Monitoring have become funded by the license fee, not by a government grant

There's then ridiculous decisions taken years ago that wasted so much money. The original iplayer with that stupid windows-only download program and the sell off of BBC Technology to Siemens (now atos) rather than taking a loan are two things that spring to mind.

Could this be "hacked"?

[Viol8]

What I mean is could someone set up a directional transmitter in just the right way so that reflections coming off the place make it look like its a few hundred metres to the north or south and thereby cause a collision?

Re:Could this be "hacked"?

[Sockatume]

Indeed, what he's describing is a pretty standard radar countermeasure. That the source is the radio broadcast background and not a special transmitter really doesn't make a difference. If anything, passive radar has the advantage that you could run a band pass filter to remove and ignore the jamming signal.

Re:Could this be "hacked"?

[jimbolauski]

It is possible but you would have to jam all the Rx antennas to accomplish this, you would have to send a different signal to each Rx antenna if you sent the same signal from a single location it can be corrected for, being passive it may be difficult to locate all the antennas to jam them. The system works by using each Rx antenna's range and doppler readings and finding a common location for those ranges and speed. What I wonder is what will happen when sun sets, the ionosphere becomes unstable at sunrise and the sun setting and could jam these systems, not being able to track planes at night would be a huge problem. Australia has a system called JORN that uses a multiple Rx antenna setup the only difference is that they don't modulate information on that signal, as long as you know the Tx signal the modulation can be corrected for.

Re:Could this be "hacked"?

[Viol8]

Except with normal radar you know roughly when and what to expect at the receiver. Using background RF you don't.

Re:Could this be "hacked"?

[Sockatume]

The same disadvantage affects the person trying to spoof the signal. He has to know what his radar reflection looks like before he can spoof it, and as an added complication he has to perform a transform on it so it looks convincing when it's coming from a different location.

Re:Could this be "hacked"?

[Rich0]

The person doing the spoofing doesn't know what signal to expect in either case. However, in one case the radar operator knows exactly what signal to expect. That is definitely an element of asymmetry that favors the active radar operator.

Imagine a radar pulse that consisted of nothing more than a crytographically signed digest of the time. Nobody can generate that signal but the operator, though you could try to replay it (which means the operator gets two returns, and the first one is the non-spoofed one). You could never get a replayed signal back to the radar in less time than your reflection, because everything is limited to the speed of light.

Passive radar has its own advantages though that favor the operator. Nobody knows that it is operating, or where the receivers are. You can have multiple receivers and they can compare notes, which makes spoofing MUCH harder as it would be almost impossible to get a consistent picture to all of the receivers which can be anywhere. It also tends to defeat stealth since many forms of stealth only protect against reflections back to the transmission source.

It is also is something anybody can implement. In theory I can build my own passive receiver in my home, and nobody would ever know I had it. You can't go transmitting radar signals over long ranges without an FCC license without getting busted fairly quickly.

Yay!

[Dunbal]

That's what we need, a system that provides absolutely NO accountability! Just crowd source "mission critical" stuff. What could possibly go wrong?

Re:Yay!

[MightyYar]

How is this "crowd sourcing"? They aren't asking the public to decode the radar, they are recognizing the waste in bandwidth to pour a constant signal into the sky when there are already dozens or even hundreds of transmitters doing this.

Re:UK and TV rader? LOL

[AmiMoJo]

US seems to be polarized between the extremely crap and extremely good. Fortunately these days it is much easier to just watch the good stuff.

Re:UK and TV rader? LOL

[dbIII]

fuck the BBC really

The last two governments over there beat you to it. Pointing out that Blair was an idiot for his "Saddam can attack London in X minutes" and more recently having a Tory's name on a list of suspected pedophiles rebounded with more interference than the BBC has seen before.

Re:UK and TV rader? LOL

[Goose In Orbit]

Not true!!! Every other show is Top Gear (with the odd Man vs Food once in a while)

Should we just rename all the channels Dave - to avoid confusion...?

Re:UK and TV rader? LOL

[Goose In Orbit]

BBC3, BBC4, CBBC, Cbeebies are part time channels occupying 2 full time slots

True - though I do wonder how much the wasted bandwidth costs just broadcasting the ident for half the day on all four of these, when they could free up 2 channels by switching from CBeebies to BBC3 (and CBBC to BBC4) at 7pm when the kids channels stop broadcasting...

Re:Interference?

[Sockatume]

It's analogous to navigating a dark room by looking at the light coming from the TV set. Although the light from the TV is a signal carrier and is constantly changing, it is consistent enough in time and space that you can use the light reflected off nearby objects to navigate.

Passive RADAR ATC Is An AWFUL Idea

[Anonymous Coward]

I think that passive RADAR for air traffic control(ATC) is an awful idea! For anything so critical and potentially life threatening as manned flight, only something as reliable as active RADAR should be used.

As for freeing the spectrum... There are other things that use 5GHz RADAR besides ATC. Marine RADAR on boats and ships immediately come to mind. I'm sure that there are others too. What frequency does weather RADAR use?

What will thry do for radar...

[John Hasler]

...when power failures or other disasters take the TV stations off the air?

Re:What will thry do for radar...

[Sockatume]

Switch to active-mode, seeing as there's nothing to cause interference with?

Re:What will thry do for radar...

[Alioth]

They will continue using SSR (no one is talking about getting rid of secondary surveillance radar, which is where you send a signal and a device on the aircraft actively replies with a packet of data), and continue using the signals from the transmitters that are outside of the power failure/disaster area. In fact this will likely be more resilient, because of instead of a very small number of special purpose transmitters providing the primary radar transmission (which are likely to be taken out by the same disaster in your scenario), you have a much greater and diverse set of transmitters providing the signal.

I'm waiting for 8G

[gsgriffin]

I don't upgrade every year. I'm just waiting for 8G so the speeds will actually be as claimed for 4G

Re:I'm waiting for 8G

[Anonymous Coward]

As a normal resident of the planet Earth, I generally find one g (9.8m/(s*s)) to be perfectly adequate.

Re:I'm waiting for 8G

[thegarbz]

I don't upgrade every year. I'm just waiting for 8G so the speeds will actually be as claimed for 4G

Obligatory Dilbert

Re:UK and TV rader? LOL

[Sockatume]

No, it's still a lot better. We still have our great original content on the terrestrial channels and the good imported shows are available with only three times three-minute ad breaks.

Frankly I'm watching more stuff on-demand or with DVD rentals than live, though. TV is dead.

Sounds more like a problem...

[Bill_the_Engineer]

Basically they mismanage their RF spectrum so much that they need to get rid of current services to make room for more services.

49 m/s^2

[FooAtWFU]

Since you ask, 5G is 49 meters per second per second. It's a whole 9.8m/s^2 better than 4G!

5G needed? Not in Canada at least.

[TheSkepticalOptimist]

Not to be a Luddite here, but is 5G really needed?

I mean at least in Canada, 5G is like giving the Amish a Porche 911, we just can't use it.

I live in a country where "unlimited data" means roughly about 2GB a month, then the carriers start throttling and doing unsavory things to make sure my wireless data experience craps out long before I hit any real limits. So all 5G is going to do for me is ensure I have crappy wireless service about 4 days after my billing cycle begins anew.

Also 4G is faster then most home broadband services, however while carriers are pushing for wireless home services its significantly more expensive given the limitation on data and, lets face it, if you have that damn tree in your yard blocking line of sight you are never gong to see the full potential of your 4G service at home. So even if 5G could offer amazing speeds that might make home use attractive, its still not going to be offered for competitive prices to the ol' wired alternatives.

I am all for the onward progress of technology, but carriers are not even offering 4G services adequately so why rush to another generation of wireless networking.

Maybe the story is different in a civilized country like England, but in Canada our telecom's are still trying to find fresh new ways of raping customers of their income and offering crippled mediocre technology that even 3rd world countries have better access to.

Re:UK and TV rader? LOL

[tehcyder]

For the moment we've still got the BBC making decent programmes and ITV and Channel 4 have at least some quality control.

I'm someone else who hardly watches TV now, if it wasn't for kids' TV and my wife enjoying soap operas I don't think we'd bother having a TV except to watch films on.

I read that as

[HPHatecraft]

"Brain Could Switch Off Airport Radar and Release 5G Spectrum".

I was like **** yeah! I bow to our New Mutant overlords.

By the time we get 5G here

[Dareth]

By the time we get 5G here.....

You will be using an IPHONE 10.
Blackberries will be just fruit, until sued by Apple for trademark infringement.
The whole world will be run on/by Androids.

Such a dumb and short sighted concept.

[xatxtal]

A lightning strike on a TV transmitter tower = off the air for some time. It cannot be fixed with power on or in high winds. A lightning strike on a radar transmitter = carry on regardless. One decent sunspot storm= TV down. One decent sunspot storm= radar still works maybe with reduced cover. I could go on all night with other reasons. The folk that come up with this dumb idea only have dollars in mind sod the safety of the public.

dangerously stupid

[whitroth]

Here in the US, there's been a lot in *increase* in radar use at airports... becuase they're now using it to view microclimes, as well... and planes have gone off the runways, and there have been other near accidents, that we now know had to do with sudden strong winds and bursts.

                mark

Re:UK and TV rader? LOL

[yurtinus]

Oooh, where are you finding this "good stuff." Could I have some, too?

Re:5G needed? Not in Canada at least.

[jjsimp]

So, Canada's telecom is as messed up and greedy as here in the US, good to know.

Re:5G needed? Not in Canada at least.

[jjsimp]

Yeah, I can agree with that. I have "unlimited data" on AT&T, but I would probably get throttled if I used more than my 2GB share. I'd be alright with the $40 if it was truly unlimited, and additional handets were no more than $10 on the plan.