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 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: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: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.

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

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: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: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

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: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.