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Hypersonic Radio Black-Out Problem Solved

Soulskill posted more than 3 years ago | from the ending-the-five-minute-panic-period dept.

Communications 88

KentuckyFC writes "Russian physicists have come up with a new way to communicate with hypersonic vehicles surrounded by a sheath of plasma. Ordinarily, this plasma absorbs and reflects radio waves at communications frequencies, leading to a few tense minutes during the re-entry of manned vehicles such as the shuttle. However, the problem is even more acute for military vehicles such as ballistic missiles and hypersonic planes. Radio blackout prevents these vehicles from accessing GPS signals for navigation and does not allow them to be re-targeted or disarmed at the last minute. But a group of Russian physicists say they can get around this problem by turning the entire plasma sheath into a radio antenna. They point out that any incoming signal is both reflected and absorbed by the plasma. The reflected signal is lost but the absorbed energy sets up a resonating electric field at a certain depth within the plasma. In effect, this layer within the plasma acts like a radio antenna, receiving the signal. However, the signal cannot travel further through the plasma to the spacecraft."

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FP (-1)

Anonymous Coward | more than 3 years ago | (#34793880)

First!

SP (-1)

Anonymous Coward | more than 3 years ago | (#34793916)

Second!

BTW is there yet a solution for CmdrTaco's micropenis problem?

Re:SP (1, Funny)

SpokeBot (884906) | more than 3 years ago | (#34794068)

If you're anus wasn't so loose, this wouldn't be aproblem

Your tax dollars at work (-1)

Anonymous Coward | more than 3 years ago | (#34793914)

It is always nice to know that governments appreciate new ways to improve on killing.

Killing protects us. Killing saves lives. Killing is better than killing.

And there are some occasional non-killing spinoffs. Isn't that great?!!?! Never mind that space exploration can produce tons more spinoffs per dollar. It doesn't involve nearly as much killing, so screw that.

Re:Your tax dollars at work (2, Funny)

MrQuacker (1938262) | more than 3 years ago | (#34794018)

Damn Obama, wasting our taxe... oh? Whats that? Russian Scientists you say?

Re:Your tax dollars at work (0, Troll)

Anonymous Coward | more than 3 years ago | (#34794090)

China testing the J-20. Good thing Obama didn't cancel F-22 produ.... oh, wait.

Re:Your tax dollars at work (1)

geekoid (135745) | more than 3 years ago | (#34794200)

since we have a 168 of them, I don't really see a problem with the project not being funded. Add to this its 20 year old tech, and not fighters are moving away from having a pilot in the craft, it was a good decision. And I love the things.

FIY: being canceled, and being no longer funded are different things.
.

Re:Your tax dollars at work (1)

ElectricTurtle (1171201) | more than 3 years ago | (#34794618)

That the tech is 20 years old is irrelevant when everybody else's is too. Further, there are NO operational interceptor drones, and it will be decades before one is more capable than an F-22. The demands of an interceptor are completely different from the surveillance and light ground attack roles that drones are filling now.

The end result of a cancelled program and a defunded program is the same: no more aircraft will be produced.

Re:Your tax dollars at work (1)

suutar (1860506) | more than 3 years ago | (#34794680)

iirc, the F22 project was defunded so that they could move the money to the F35 project, which seems to be progressing nicely...

Re:Your tax dollars at work (1)

ColdWetDog (752185) | more than 3 years ago | (#34795796)

iirc, the F22 project was defunded so that they could move the money to the F35 project, which seems to be progressing nicely...

You must work in Marketing. "Progressing Nicely?" [armybase.us]

Re:Your tax dollars at work (1)

suutar (1860506) | more than 3 years ago | (#34796336)

Not marketing, just insufficient information. Thanks for the pointer :)

Re:Your tax dollars at work (1)

slick7 (1703596) | more than 3 years ago | (#34798566)

iirc, the F22 project was defunded so that they could move the money to the F35 project, which seems to be progressing nicely...

You must work in Marketing. "Progressing Nicely?" [armybase.us]

Probably more like a PR spin-doctor.

Re:Your tax dollars at work (1)

Grishnakh (216268) | more than 3 years ago | (#34795840)

You can't have an advanced fighter jet without a pilot in the craft. Remote-control aircraft work fine for fighting stone-age enemies on the ground in backwards countries who have no ability to jam your radio signals, but that won't work when fighting someone with the same level of technology, in aerial combat.

Basically, we're giving up on the ability to fight anyone with similar technology, and concentrating only on fighting insurgents on the ground.

Re:Your tax dollars at work (1)

darthdavid (835069) | more than 3 years ago | (#34797508)

You don't need to send radio signals to your drone if you have a good enough computer/smart enough software on board.

Re:Your tax dollars at work (1)

Grishnakh (216268) | more than 3 years ago | (#34800758)

Huh? Computers aren't artificially intelligent yet.

Re:Your tax dollars at work (1)

drinkypoo (153816) | more than 3 years ago | (#34801658)

Huh? Computers aren't artificially intelligent yet.

Have you played any flight combat simulators? It's not hard to get the computer to whip a human's ass. The hard part is getting enough data into the computer to allow it to make "intelligent" decisions.

Re:Your tax dollars at work (1)

lewko (195646) | more than 3 years ago | (#34799952)

Don't worry. Israel has your back.

Re:Your tax dollars at work (1)

Confusador (1783468) | more than 3 years ago | (#34802024)

If you can save enough money in production by removing life support and in operation by reducing personnel, it's conceivable that I'm fielding 10 drones for each of your pilots. And my pilots gain experience even when their craft is destroyed. In a prolonged, real shooting war these things add up.

Of course, if it ever comes to that we'll see both sides fielding mixed squadrons so they get the best of both, at least for the foreseeable future.

Re:Your tax dollars at work (1)

Vitriol+Angst (458300) | more than 3 years ago | (#34802254)

If it ACTUALLY gets into a shooting war between some country like the USA and China -- FIRST, all the hunter-killer satellites that NOBODY has in space will go out and attack other satellites and GPS systems. IF any side starts to win THAT war, one bomb from either country can render Space un-usable for years until a billion fragments stop traveling through it at supersonic speed.

THEN, millions of tiny bug-like robots, that just seek out humans will be sent by hyper-sonic torpedoes -- ones that can travel in their own shockwave underneath the ocean and avoid all radar and anti-missile systems we currently have.

No nukes of course, until Rich people can get those bunkers built -- in ten years, well, the surface of the planet could just turn to glass. No need for fighter jets or drones then.

>> BUT, if the rich people don't have bunkers that they can comfortably live in for 3 generations, this future war will be all electronic.

IF we start winning, China will then send out a RADIO KILL SIGNAL, and all those chips we bought from them will stop working -- including that super cheap Microwave Oven you have at home. So when it gets to this point, you will still be unaware there even was a war, but all the banks will change to something like "People's Bank of America."

Your blender and microwave, however, will mysteriously all need to be sent back to the manufacturer for repair, and you will pay for that in Yuan.

does the ratio matter (1)

way2trivial (601132) | more than 3 years ago | (#34802072)

Remote controlled drone vs. live pilot in the seat I concede that for now the pilot will likely win out.

what if it's 3 drones to one live pilot

what if it's 7

what about ten?

Re:does the ratio matter (1)

Vitriol+Angst (458300) | more than 3 years ago | (#34802302)

Come on, the pilot is mostly a delivery service for MISSILES.

He targets another plane or object and fires a COMPUTER CONTROLLED MISSILE.

The Pilot even moves a joystick, which turns his commands into "fly by wire" adjustments, that require a computer to adjust the plane about a thousand times a second.

The Pilot, is already remote controlling the plane, and the plane is sending out remote-controlled weapons called "missiles" -- the ONLY thing we are really arguing about, is where the human is sitting and CAN someone block that signal?

If someone can block the signal to the plane, then you can have a smarter computer onboard -- it's at what point you determine the target that really matters. If you KNOW the target -- no need to have a human on board. If you are finding the target, a hundred remote drones can be involved. So, the ONLY part where a human pilot has the advantage, is in a situation where you FIND and DESTROY the target in one sortie.

The FUTURE war is either precisely targeted, or it's going to be massive numbers of decoys and drone bombs to try and get them all. In the first case, you have a quick strike -- and therefore, not much chance for the enemy to prevent your attack -- on the second, it's just a game of numbers and all your drones get faster, cheaper, smaller -- there is no advantage to an aircraft carrier or a tank, they are just bigger targets.

If there is no worry about collateral damage, and you can get the cost down for drones -- well, a human pilot is just a liability.

>>> Having a Human pilot, it seems to me, is just a legacy thing that we do because all our wars are very assymetric. We bring in humans after we've destroyed the ability of the enemy to defend against aircraft. We use night-sighted helicopters and mow down a group of people from a mile away as they shoot into the dark in random directions. Then, the enemy adapts and takes off their uniforms, and we don't know friend from foe.

So, the pilots we have today, might as well be bus drivers with bombs for all the "air fighting" they are going to see. And if we get in a war with a REAL adversary, well -- I think all the banks and the corporations that run those two countries will just VETO that idea.

Re:Your tax dollars at work (1)

Vitriol+Angst (458300) | more than 3 years ago | (#34802228)

Y...Basically, we're giving up on the ability to fight anyone with similar technology, and concentrating only on fighting insurgents on the ground.

Well, actually, that at least sounds consistent. Since MOST of our weapons are produced by private corporations -- and THEY have weapons plants in some of those "Potential Enemy" countries -- just shooting people too poor to jam your radar and PRETENDING to have air craft carriers for some other reason than to spend lots of money on these same corporations seems to be working out great for all the Players involved.

>> If you can find a way to JUST shoot poor people, than that would be a VERY smart bomb. GE would hire you in a second.

Re:Your tax dollars at work (2)

zach_the_lizard (1317619) | more than 3 years ago | (#34794088)

The space program has been used for military research and military purposes. There's quite a bit of overlap between sending a man to orbit and sending a missile to orbit. That GPS satellite can be used to get you from point A to B or that ballistic missile to Moscow. Satellite cameras to search the stars aren't altogether different from spy satellites to search the ground. Maybe some of the experience they've gotten from, say, the Mars rovers was useful in building the various military drones they have now.

I think it's fair to say that the military would find ways to use civilian technology in relevant fields, and space exploration has some pretty big overlaps.

Re:Your tax dollars at work (0)

Anonymous Coward | more than 3 years ago | (#34794512)

...or that ballistic missile to Moscow

If you mean Moscow, Russia, then "to within 200 miles of Moscow" would be more accurate. Getting closer would be very problematic for a ballistic missile, unless A-135 has been sold for scrap like so much else in Russia.

Re:Your tax dollars at work (2)

mrxak (727974) | more than 3 years ago | (#34795608)

The A-135 can only really defend Moscow against a single warhead, or just a handful at the most. The radar system itself is susceptible to suppression, seeing as how there's only one pillbox providing support for the interceptors. Only the first wave defense is likely to be effective, and there's only 32 of those missiles, which would hardly put much of a dent into a serious ballistic missile attack, considering the number of decoys and warheads implemented in modern missile systems. The second wave defenses, while more numerous, are non-nuclear now and probably wouldn't intercept much of anything. They were designed for nuclear warheads originally, something which of course would irradiate much of Moscow anyway. There may still be some nuclear warheads in the second wave, but stopping the enemy missiles from striking your city isn't all that great if your own missiles kill you anyway.

This is all, of course, predicated on the idea that the A-135 is still operational. There's some evidence that it's not, really, and only used for "tests" whenever the US starts thinking about upgrading their own ABM systems.

Re:Your tax dollars at work (1)

gstoddart (321705) | more than 3 years ago | (#34795650)

I think it's fair to say that the military would find ways to use civilian technology in relevant fields, and space exploration has some pretty big overlaps.

And, indeed, that much of what we now consider to be civilian technology was developed initially for military applications. The internet, for example, was funded by DARPA. So was GPS -- can't lay my hands on a good list, but I'm sure it's quite extensive.

Re:Your tax dollars at work (2, Insightful)

geekoid (135745) | more than 3 years ago | (#34794254)

You're really limit in your thinking.

Technology is constantly developed to make killing more precise; which means LESS killing.

And there are a hell of a lot of spin-offs that are used in civilian markets. I don't see why you have created some sort of demarcation between killing tech and non killing tech. there is just tech that is used. The same tech is often used for killing as it used for non killing.

Re:Your tax dollars at work (0)

Anonymous Coward | more than 3 years ago | (#34794832)

"You're really limit in your thinking. Technology is constantly developed to make killing more precise; which means LESS killing."

Ah, the only person _limited_ (good spelling, genius) in their thinking is you. How many people die in violent conflict has a lot more to do, for my money, with the political will of national leaders to start wars and kill people. Drone missiles, for example, may be more precise than carpet bombing, but that just means an expansion of targets which formerly would have been off-limits, each with their own (admittedly smaller) set of collateral damage.

Look at how many people have died in Pakistan from drone missile strikes at apartments. It's like 10-12 deaths an attack, usually aimed at one person (the 'target'). Or wedding parties in Afghanistan. Or the fact that our whole fucking invasion of Iraq (with hundreds of thousands of civilian casualties) was possible in part b/c Americans like you were sold on how our technologically sophisticated supersoldiers can kill the bad guy and save the baby while feeding the hungry. It's almost like you think the tomahawks are dropping food aid out a chute on the way to the target.

The value of our military R&D budget is a different question. I'm just pointing out how fatally flawed your argument is.

Re:Your tax dollars at work (1)

srussia (884021) | more than 3 years ago | (#34797790)

Technology is constantly developed to make killing more precise; which means LESS killing.

And there are a hell of a lot of spin-offs that are used in civilian markets. I don't see why you have created some sort of demarcation between killing tech and non killing tech. there is just tech that is used. The same tech is often used for killing as it used for non killing.

Gatling gun, A-bomb, H-bomb, Napalm, MOAB... precise enough for government work I guess.

Re:Your tax dollars at work (1)

perryizgr8 (1370173) | more than 3 years ago | (#34801072)

You're really limit in your thinking.

Technology is constantly developed to make killing more precise; which means LESS killing.

you mean like the hydrogen bomb? the one which can precisely destroy a WHOLE city? technological progress does not automatically mean more precise killing, sometimes it also enables mass killing.

Re:Your tax dollars at work (1)

Beardo the Bearded (321478) | more than 3 years ago | (#34794608)

I'm a military contractor, you insensitive clod.

Re:Your tax dollars at work (0)

Anonymous Coward | more than 3 years ago | (#34795026)

"Never mind that space exploration can produce tons more spinoffs per dollar. "

Can't. Never has, never will. Space has always been a PR stunt to hide war technologies, mixed in with some saber-rattiling. The geeks with their wide-eyed wild fantasies and delusions of orbital factories and Moon mining are so far away from being practical and economical, it's laughable. It will simply NEVER EVER work, EVER. As long we have chemical reactions, oil and rocket engines. See that changing anytime soon? Yeah, didn't think so.

Re:Your tax dollars at work (1)

perryizgr8 (1370173) | more than 3 years ago | (#34801086)

The geeks with their wide-eyed wild fantasies and delusions of 8GB RAM and Quad Core Processors are so far away from being practical and economical, it's laughable. It will simply NEVER EVER work, EVER.

Re:Your tax dollars at work (0)

Anonymous Coward | more than 3 years ago | (#34807814)

Do you see where maybe, just *maybe* the energy and technologocial limits of materials are maybe, just *maybe* a little bit *different*? Amazing. So deluded, basic physics and engineering go out the window.

Speaking of windows, look out yours. What do you see? The same houses, roads, cars, planes, clothes, food and oil-powered agriculture that was there since WWII.

There is simply no way, ever, that space is going to pay off. It's OVER. FINISHED.

Space Nutters have had DECADES to show us something, anything. End result? Sweet. Fuck. All.

But hey, don't listen to me. Listen to Dr Stephen Pyne.

CBC Quirks and Quarks [www.cbc.ca]

Listen to the "January 8 — Homage to Voyager." episode when it's out. I remember something like "the ISS is not exploring space, it's not even science." when I heard it on the radio today.

But hey, there's more!

http://www.spacedaily.com/news/oped-04y.html [spacedaily.com]

http://findarticles.com/p/articles/mi_m1134/is_9_115/ai_n27050480/?tag=content;col1 [findarticles.com]

Or my favorite:

http://www.cbc.ca/quirks/episode/2009/09/19/tiny-trex-curing-colour-blind-monkeys-walking-on-our-own-two-feet-space-based-solar-power/ [www.cbc.ca]

Where the scientist is barely holding back from laughing out loud at the outlandish "space-based solar power" projects. Hey, wasn't there one just last year? Where is it now? Oh yeah, oblivion.

We've hit limits in energy sources and propulsion technologies. Rockets take our technology to the outer limits of what's possible with materials. Unless you find new elements in the table of elements, what we have is *it*.

That 747 you saw when you looked out the window? Maiden flight was 1969. Hasn't changed in over four decades. Why? The technology and basic physical reality hasn't changed. It can't. But you think we'll be doing space? Ridiculous.

The fact we have fast computers today on a square inch of silicon doesn't help you move mass around. It's that basic. The fact you don't get that is both sad and terrifying.

Black out? (1, Insightful)

Anonymous Coward | more than 3 years ago | (#34793920)

Is this PC? Maybe use "slave out"? What do you think, Linda?

Re:Black out? (1)

MouseR (3264) | more than 3 years ago | (#34794642)

Montag remains incredulous over this.

Re:Black out? (1)

coolsnowmen (695297) | more than 3 years ago | (#34795696)

WTF are you talking about. Clearly in the US this gets replaced with "African-American Out."

Re:Black out? (1)

sjames (1099) | more than 3 years ago | (#34798868)

What about all those African-Americans in Africa?

No, they haven't. (1)

blair1q (305137) | more than 3 years ago | (#34793934)

The SNR and BER of that scheme are going to suck.

Re:No, they haven't. (1)

EdZ (755139) | more than 3 years ago | (#34794174)

Very very little:1 is still better than 0:1

Re:No, they haven't. (1)

blair1q (305137) | more than 3 years ago | (#34794498)

No, it isn't. Noisy telemetry is balls. It will mislead you. And you can't make an error-correcting code to handle the number of bits that will be borked by this system (which is why I mentioned BER). Not that you'd waste your bandwidth on elaborate error-correcting codes anyway.

Best strategy: save up the data and read it later. There's not much you can do in real-time at that point anyway. It knows where to go, and you're not going to need to change that during that phase of its flight.

Re:No, they haven't. (1)

Confusador (1783468) | more than 3 years ago | (#34801978)

I don't know, "Maybe we shouldn't have launched that nuke after all" seems like it would be a nice command to be able to send. This solution might not work, but it's still a useful problem to work on.

Re:No, they haven't. (4, Informative)

bughunter (10093) | more than 3 years ago | (#34794176)

FTFA:

Korotkevich and co say the weakness of the transmission signal doesn't matter because ground-based receivers can be made hugely sensitive, certainly much more so than mobile ones.

Considering we can communicate with interplanetary (and now some technically interstellar) probes with received signal strengths on the order of -200 dBm [baylorschool.org] , and we can build arbitrarily large transmitters/receivers on the ground, and health and status telemetry doesn't require huge bandwidths (on the order of 10^2 bps), I'd say he's right.

Re:No, they haven't. (1)

kaiser423 (828989) | more than 3 years ago | (#34794442)

You do realize that these things go so fast that you have to track them across large swaths of ocean, right? You can't really build an arbitrarily large receiver in the ocean for a reasonable cost. Heck, you can't even put a ton of arbitrarily sized trackers on the ground either without massive expenditure, probably larger than a lot of the hypersonic test projects budgets.

Re:No, they haven't. (1)

blair1q (305137) | more than 3 years ago | (#34794546)

You need that for interstellar probes because you have no other choice. And you can accept that data rate because you have nothing but time. And it fits into your power budget besides.

But that's a much lower-noise situation.

This will be like trying to talk while standing in jet wash. The 1 in 10 words you can make out will not be enough information to be useful in the time during which you're still in the jet wash. Better to wait until you've stopped tumbling down the tarmac and the plane is gone and then ask "say again?"

Re:No, they haven't. (0)

Anonymous Coward | more than 3 years ago | (#34795060)

This will be like trying to talk while standing in jet wash. The 1 in 10 words you can make out will not be enough information to be useful in the time during which you're still in the jet wash. Better to wait until you've stopped tumbling down the tarmac and the plane is gone and then ask "say again?"

How about if you are dead by then?

FFS (From the Fine Summary),

Radio blackout prevents these vehicles from accessing GPS signals for navigation and does not allow them to be re-targeted or disarmed at the last minute.

You comment remind me of people that say "you can't do that because I say it ain't worth it". Of course then you end up with Russians having supercavitating torpedoes while Americans were saying they were impossible.

http://en.wikipedia.org/wiki/VA-111_Shkval

Re:No, they haven't. (1)

blair1q (305137) | more than 3 years ago | (#34796296)

How about if you are dead by then?

How am I dead? I'm on the ground. The guys in the re-entering capsule already have all the information, and control of the vehicle. I'm sure as shit not going to try to steer it with an extra 500 ms of latency in the loop. By the time the data even gets through to me it's old. Doesn't matter if it's 500 ms old or 5 minutes old.

As for what the FFS said, the blackout is a short interval in the flight, and it's ballistic. You're not going to maneuver in that beyond attitude control, The ability to do so would require shielding more of the vehicle from heat and dynamic overpressure. Any retargeting can be done before you hit atmosphere or once the plasma subsides.

And I'm not saying it's impossible. I am saying it ain't worth it because the return is nothing practical. We do want supercavitating torpedoes; they're of some practical value. It was a mistake to say it wasn't possible. But we won the cold war without them, so we made the right decision not spending on making them possible, and the pinkos didn't.

Re:No, they haven't. (1)

ppanon (16583) | more than 3 years ago | (#34802100)

As for what the FFS said, the blackout is a short interval in the flight, and it's ballistic. You're not going to maneuver in that beyond attitude control, The ability to do so would require shielding more of the vehicle from heat and dynamic overpressure. Any retargeting can be done before you hit atmosphere or once the plasma subsides.

Really? What if there is something on an intercept course that's taking advantage that the re-entering hypersonic body is plasma blind and on a defined trajectory? Seems like having some spy eyes telling it that it's going to be dead if it doesn't deke might be worth taking some risk with some momentary overpressure. Especially if you've built-in just a little extra ablative shielding and structural strength to take it for a short period.

Re:No, they haven't. (0)

Anonymous Coward | more than 3 years ago | (#34802680)

Have you bothered to read anything at all before spewing shit onto the internet? The summary? The summary someone reposted for you and you still ignored?

Of course things with pilots don't give a fuck about 60 seconds without communication. The "vehicles" they're talking about are things like ICBMs. You would be dead if the missile strike could not be called off and it hit your town.

Re:No, they haven't. (1)

bughunter (10093) | more than 3 years ago | (#34798720)

Considering a typical terrestrial noise floor is about -90dBm, your talking in a jet wash analogy is not inaccurate for either scenario.

Because SNR is SNR (assuming we're not getting into the realm of ECM or correlated noise).

SNR and channel bandwidth (and a few other things we can hold constant in this example) give you your BER. If your BER is too high, then you either need to talk louder, narrow your bandwidth, or use an error correcting code. Usually some combination of all three. There are solutions, and plenty of engineers ready to take on the challenge.

The point is, they've gone from concluding it's impossible to showing us how it's possible. If you want to continue believing it's impossible, go ahead. Someone else will solve the problem.

Re:No, they haven't. (1)

shdragon (1797) | more than 3 years ago | (#34794764)

Thanks for the Voyager transmitter link info...that was a really interesting read.

Cheers!

Re:No, they haven't. (1)

MacGyver2210 (1053110) | more than 3 years ago | (#34795098)

I know this is /. but '100' is actually fewer characters than '10^2'.

Re:No, they haven't. (1)

DarkOx (621550) | more than 3 years ago | (#34795372)

well since this is slashdot, the parent post said 10^2bps and that is way fewer than 100 characters which might be 6, 7, usually 8 (ASCII), or 16 bits each.

Re:No, they haven't. (0)

Anonymous Coward | more than 3 years ago | (#34795634)

> I know this is /. but '100' is actually fewer characters than '10^2'.

Agreed. Unless he meant 2^10, he's YAATTLC (yet another asshole trying to look cool).

The shuttle doesn't (currently) black out (5, Informative)

by (1706743) (1706744) | more than 3 years ago | (#34793990)

http://en.wikipedia.org/wiki/Communications_blackout#Reentry_communications_blackouts [wikipedia.org]

Until the creation of the Tracking and Data Relay Satellite System, the Space Shuttle would, like Gemini, Mercury, Apollo, and others, endure a 30 minute long communications blackout before landing. However, the Shuttle can communicate with a Tracking and Data Relay Satellite during re-entry. This is because the shape of the Shuttle creates a "hole" in the ionized air envelope, at the tail end of the craft, through which it can communicate upwards to a satellite in orbit and thence to a ground station.

Re:The shuttle doesn't (currently) black out (-1, Redundant)

Desler (1608317) | more than 3 years ago | (#34794054)

And this article wasn't talking about the space shuttle. In fact the word "shuttle" doesn't exist in either the summary or the article.

Re:The shuttle doesn't (currently) black out (1)

Anonymusing (1450747) | more than 3 years ago | (#34794070)

Uh... the word "shuttle" is in the summary... end of the second sentence.

Re:The shuttle doesn't (currently) black out (1)

by (1706743) (1706744) | more than 3 years ago | (#34794076)

From TFS (my emphasis):

Ordinarily, this plasma absorbs and reflects radio waves at communications frequencies, leading to a few tense minutes during the re-entry of manned vehicles such as the shuttle.

Re:The shuttle doesn't (currently) black out (1)

blizz017 (1617063) | more than 3 years ago | (#34794078)

And this article wasn't talking about the space shuttle. In fact the word "shuttle" doesn't exist in either the summary or the article.

Really? Damn.. i guess I just imagined reading this line:

Ordinarily, this plasma absorbs and reflects radio waves at communications frequencies, leading to a few tense minutes during the re-entry of manned vehicles such as the shuttle.

Re:The shuttle doesn't (currently) black out (1)

Desler (1608317) | more than 3 years ago | (#34794096)

Yes, I was wrong about the summary, but the article made no mention of it at all. The article was talking about all hypersonic vehicles in general. The summary writer added that in superflously.

Re:The shuttle doesn't (currently) black out (1)

by (1706743) (1706744) | more than 3 years ago | (#34794430)

Actually, the shuttle's solution is alluded to in the article (I haven't read the paper, though):

Another is to shape the craft so that the plasma does not form in certain areas where a radio antenna can be placed. But this means the entire vehicle has to be designed around the communications system, which then cannot be changed.

Yet another idea is place the radio antenna in the nose spike so that it sticks out beyond the plasma. This allows radio communication until the antenna wears away due to ablation.

You're right that this is an entirely different method for communicating with hypersonic objects.

Re:The shuttle doesn't (currently) black out (0)

Anonymous Coward | more than 3 years ago | (#34794084)

Ordinarily, this plasma absorbs and reflects radio waves at communications frequencies, leading to a few tense minutes during the re-entry of manned vehicles such as the ---> shuttle. ----

Re:The shuttle doesn't (currently) black out (3, Insightful)

si3n4 (540106) | more than 3 years ago | (#34794240)

thanks for the comment - I realize this quickly devolved into a discussion about what was or wasn't said in the article but it is interesting that the shape of the vehicle can create a hole in this plasma and thus provide another solution to the issue . Maybe it's not always possible to design the object involved to create this hole and the plasma antenna is a useful alternative, but in any case it was interesting to me to know this other 'solution' exists....

Re:The shuttle doesn't (currently) black out (1)

DerekLyons (302214) | more than 3 years ago | (#34798044)

It's fairly trivial to design a vehicle to create the 'hole' - the problem is that the 'hole' is fairly narrow and always pointed to where you're coming from. This isn't always a useful direction.

Re:The shuttle doesn't (currently) black out (2)

BitZtream (692029) | more than 3 years ago | (#34795278)

It does actually black out, but for a much shorter period of time during a transition between flight attitudes. Its less than 30 seconds however it does still loose communications during the worst parts of reentry, even with a relay off its tail.

Subject (1)

Larry The Black Fag (812280) | more than 3 years ago | (#34794042)

Does this mean my 3G data card will work when I travel hypersonically?

Or, you could just do it this way... (1)

slew (2918) | more than 3 years ago | (#34794066)

http://www.freepatentsonline.com/3758862.html [freepatentsonline.com]

(except it's patented)...

Re:Or, you could just do it this way... (1)

GottMitUns (1012191) | more than 3 years ago | (#34794178)

Filed in 1970...

Re:Or, you could just do it this way... (2)

eggled (1135799) | more than 3 years ago | (#34794876)

That's actually exactly what they're doing, but slightly different approaches.

Patent:
Uses adaptive impedance matching to allow signal propagation through the plasma.

This project:
Uses adaptive frequency matching to allow signal re-transmission through the plasma.

Same net effect, exploiting the same properties (The patent changes the impedance of the transmission circuit to match the plasma, while TFA describes varying the frequency until we hit an impedance match with the plasma (changing the frequency changes the effective impedance of the plasma).

Not solved! (2)

erroneus (253617) | more than 3 years ago | (#34794162)

I read the full summary. The last sentence that the signal cannot travel into the craft from the plasma. How is that solved?

Re:Not solved! (2)

Monkeedude1212 (1560403) | more than 3 years ago | (#34794194)

Sounds like all they need to do is hook something onto the ship that can read signals inside the plasma, some kind of antenna that can withstand the stresses associated.

Essentially the signal doesn't travel all the way through the plasma, thats why theres a blackout.

But we never thought about trying to receive from inside the plasma.

Re:Not solved! (3, Funny)

TopSpin (753) | more than 3 years ago | (#34794224)

How is that solved?

A stubby little plasma antenna lives in the plasma stream. It's made of hypereutectic unobtainium, a exotic form of unobtainium unique to Russian science.

Re:Not solved! (0)

Anonymous Coward | more than 3 years ago | (#34794672)

Hypereutictic unobtainium, the unobtainum made of magnetic fields..

Re:Not solved! (0)

Anonymous Coward | more than 3 years ago | (#34795168)

No, you're thinking of hyperbaryonic unobtainium.

Note that there is a difference between hypereutectic unobtanium (from the GP) and Hypereutictic unobtanium (which you wrote).

Re:Not solved! (0)

Anonymous Coward | more than 3 years ago | (#34800040)

Or you just trail the antenna(s) out of the ass-end of the hypersonic vehicle into the cooler part of the plasma.

Yeah yeah... Everyone sees the brightest and hottest part of the plasma on the front of a re-entry vehicle and thinks of that first, but there's still decent long tail of plasma behind it. It's not the temperature of the ions that matters, it's the fact that they're there. It's likely they tap into that and use some form of cathode effect.

TFA is revealed! (4, Informative)

Protoslo (752870) | more than 3 years ago | (#34794620)

Well, I read the full introduction of the paper, and the conclusion, skipping only the detailed plasma physics models & calculations. They do mention the strategy of putting an antenna through the plasma which can last as long as one fuel tank before it ablates, but they instead propose that (more elegantly) a small commercially-available 3 kW high frequency klystron amplifier (a lot less power than the radar) be placed at the surface of the aircraft, where it will disrupt a very small region of the plasma in a manner that will scatter ~.7 - 2% of the original incoming signal (which will resonates in a layer of the plasma) back to the aircraft; that is enough power for a 5 m. antenna and a commercially-available high sensitivity GPS receiver to pick it up. There is an analogous explanation for outgoing signals. They account for quite a few confounding plasma effects, acknowledge that there are some others that can't be modeled so clearly (or maybe they didn't think of), but predict that getting the system to work would be a not-so-difficult engineering challenge.

My first thought was, "Boy, I hope all the space opera authors read this preprint: no more signal attenuation from the plasma engines in the atmosphere!" Now there is one more area in which reality is exceeding a certain segment of--rather soft--science fiction (that I am only familiar with--AHEM--because of Baen's visionary no-DRM any-format ebook policy).

What about subspace? (1)

SoonerSkeene (1257702) | more than 3 years ago | (#34794170)

The cause of, and solution to, all technological problems in the 23rd century.

Re:What about subspace? (2)

adonoman (624929) | more than 3 years ago | (#34794264)

I'm pretty sure it would all work out if they just reversed the polarity of the tachyon emitter.

Re:What about subspace? (1)

SoonerSkeene (1257702) | more than 3 years ago | (#34794370)

Of course, it's just like (incredibly simplistic 21st century metaphor). It was right in front of our eyes!

Re:What about subspace? (1)

Existential Wombat (1701124) | more than 3 years ago | (#34797392)

As long as it was all channeled thorugh the front deflector, of course.

Recycled news (1)

l2718 (514756) | more than 3 years ago | (#34794214)

At the end of TFA they give the original reference, a paper preprinted in 2007 [arxiv.org] . One way to tell if this holds water is to see if other research groups have done follow-ups in the intervening three years.

Just a little fly in the ointment.... (0)

Anonymous Coward | more than 3 years ago | (#34794216)

Just one glitch-- you can transmit with a plasma antenna, but you can't receive worth a darn.

You see the plasma is a bunch of random electrical discharges and accelerated particles, which put out a strong wideband noise, quite a few orders of magnitude stronger than any signal you might wish to receive.

And what's the rush? Re-entry plasma is time-limited to just a handful of minutes. Astronauts should be able to get along without Wi-Fi for that long.

Re:Just a little fly in the ointment.... (1)

mlts (1038732) | more than 3 years ago | (#34794384)

The closest analogy I can liken it to are plasma speakers. They are excellent at reproducing sound. However, using plasma as a microphone, they would take a lot of work and amplification to get any meaningful signal back from them.

Re:Just a little fly in the ointment.... (1)

Chyeld (713439) | more than 3 years ago | (#34795544)

On the other hand we might prefer that a thermonuclear warhead mounted on a cruise missile heading for China be able to receive the recall signal all the way up to the point where it goes 'boom', you know just in case Joshua is acting up again.

Unless Gene Hackman and Denzel Washington are on board, in which case, it wouldn't matter either way, they'll get into an alpha male fight and someone will have to hold the leash for Gene's Poodle while the brass chews Denzel out.

What the article didn't say... (0)

Anonymous Coward | more than 3 years ago | (#34795480)

What I find most interesting is what the article didn't say. Oh, there is a plasma surrounding hypersonic vehicles, thats true. But, dear reader, there is *also* a plasma around military aircraft that use plasma to jam radar. Its not just the oblique features of the aircraft that contribute to a low radar signature (or the turbine intake that contributes to a high radar signature). Military aircraft have used RAM (radar absorbing material) in the paint of these aircraft --basically the paint acts like very small radar absorbing cavities that allows radar in, and then it bounces around in the paint, slightly heating it, and not reflecting it. But besides these two methods of jamming radar, you can put a plasma (artificial St. Elmos Fire), around parts of the aircraft with a high signature, and as the article states, the EM radiation that is the radar pulse can't get through it, and can't reflect off it. So you are invisible. Now this article and the technology it describes solves re-entry radio blackouts, but also the military kind. Thanks for reading....

Re:What the article didn't say... (1)

Nerull (586485) | more than 3 years ago | (#34801644)

Invisible expect for the whole fact that you're now so bright in IR that people could spot you from another planet, not even mentioning all the other EM noise emitted.

You may be slightly less visible on radar, but you're screaming "I'M HERE!!!!" in so many other ways it doesn't matter.

Disarn missiles at the last minute? Unlikely (1)

93 Escort Wagon (326346) | more than 3 years ago | (#34797540)

The standard argument against being able to remotely disarm missiles has been that including such a mechanism opens the door for the enemy potentially figuring out how to do it - it's not about the ability to communicate.

Captain we're being hailed... (1)

twebb72 (903169) | more than 3 years ago | (#34832842)

@MajorTom: We just started our re-entry...
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