Radar versus Stealth: Passive Radar and the Future of U.S. Military Power

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Hamilcar 10/17/2009 9:17:26 AM

I don't like to comment what other say cause its always ends up in a pointless spiral. but here i don't really have the choice:

to Hamilcar

"Signal smear across the wavelength was my point. A b;lob detector at long range does you no targeting good. You need that direct return on a known bearing with the speed component extracted from the signal."

"Signal smear across the wavelength was my point"

well... are you talking about doppler effect here? cause thats not very clear.

Yes it isvery clear.. Doppler is measured as a change in the nature of frequency of the return as interval measured by the comparison against the time of the transmitted signal.

A blob detector at long range does you no targeting good. You need that direct return on a known bearing with the speed component extracted from the signal.

First, blob detection algorithm have little to do with radar processing technique, its only a way to find specific pattern like boxs corner... but i think you are talking about resolution here... and ya at long range you have less resolution. About the direct return part... well ya the RETURN must be direct... like for all radar! About speed you need 2 ping with old traditional scanning radar and only 1 with doppler one.

1. Radars don't ping, they paint.

2. Resolution is a function of wavelength. Additional comment: don't confuse hard return and soft return. Third you seem to think you need two pulses (not pings) to determine a doppler off a scanning radar? You are confused. A scanning radar scans it can either Doppler or not Doppler. That depends entirely on whether there is a clock function and frequency comparator. The Doppler sensitivity depends on how good the clock is and how good the comparator is. One return is what some radars require.

3. If you reread what you wrote you might understand why the only Doppler radar is a transmitter receiver type. Bi-statics and multi-statics are not Doppler radar nor can they be.

About what bluewings12 said:

My 2 cents .

There is a noticeable difference in between tracking a VLO aircraft on radar and the capability of an EM missile seeker to get a lock and a track on the same VLO fighter .

Then , there are ECMs ...

I said:

your statement sound perfectly right to me

Your answer was:

It wasn't. If you understand what a scalar and a vector is, you'll understand why it was not accurate. What works for a chaser missile that pursues a radiating target at very close range, does not work at all for long range air search radar. Example: in the case of infrared chaser missiles the very atmosphere acts as an insulator and contrast masker for a distant aircraft. If it is signal managed on top of that, then the IR or RH (radar) missile is useless at any but gun ranges. That is the whole purpose of such signal management, (low observable) whether X or L band, or IR..

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Hamilcar Additional; 10/17/2009 9:22:26 AM

I just noticed that you said there was no way to attenuate heat below a detection thresh-hold at distance in the atmosphere.

You need this:

Infrared through the atmospher...

If you don't know, ask.

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FJV 10/17/2009 9:54:00 AM

My hunch is that the vast majority of relevent issues with stealth are not discussed on the internet.

My second hunch is that a determined capable enemy can develope something that can detect stealth in 10 years. And there are several options for achieving this. Some are not even technical, but tactical in nature.

If that happens the 5th generation platforms immediately become 4th generation in my opinion.

Personally I'm getting less and less impressed by stealth to be honest.

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Hamilcar 10/17/2009 10:05:19 AM

My hunch is that the vast majority of relevent issues with stealth are not discussed on the internet.

True.

My second hunch is that a determined capable enemy can develop something that can detect stealth in 10 years. And there are several options for achieving this. Some are not even technical, but tactical in nature.

Also true, but then the signal management side continues to improve.

If that happens the 5th generation platforms immediately become 4th generation in my opinion.

Or the platforms will adapt. Stand off weapons and anti-transmitter weapons are just two gross adaptations, we see. More subtle signal interference measures are possible. Even the weather helps the attacker.

Personally I'm getting less and less impressed by stealth to be honest.

I'm more concerned about it becoming a substitute for good tactics and strategy. A technical exploit is a means to an end, it is not the end itself.

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warpig 10/17/2009 10:44:11 AM

If that happens the 5th generation platforms immediately become 4th generation in my opinion.

Personally I'm getting less and less impressed by stealth to be honest.

The only way the F-22 and F-35 merely become the best 4.5 Gen fighters is if our most likely threats all make operational on a widespread scale reliable means for not only detecting LO aircraft, but also tracking them, handing their tracks off to fighters and SAM units that also can track them, and then engaging them with missiles or other weapons that can hit them.

Writing some articles about how some people have found that multistatic radars might increase the ability to track LO aircraft is a long way from doing all the above. Furthermore, once again, we are not and will not remain still in our LO technology development, and in developing the tactics, techniques, and procedures to capitalize on LO and maintain the advantage made possible by LO--and yes, of course that certainly also includes network approaches that also benefit from the whole range of non-LO capabilities we also have, things like C4ISR, airborne electronic attack, and SEAD/DEAD. Why wouldn't it?

Stealth is a huge advantage and will remain so for a couple decades at least.

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RedParadize 10/17/2009 1:55:48 PM

About the numeric designation of generation of fighter, i will just say it doesn't mean that much. Its only for political purpose.

Hello again Warpig:

"Stealth is a huge advantage and will remain so for a couple decades at least."

I would go more far, Raptors Stealth will always be a advantage, it will just become more marginal over time.

About stealth itself, it is nothing more then a strategic/tactical advantage. And in that, its not different then camo, or any other way to conceal your position and objective to your enemy. The gained advantage depend on the usage, and its not a substitute to raw firepower and mass.

To Hamilcar

I have 3 question for you:

If you have a Radar, antena diameter: 980 mm, power output: 8 kW. with captor sensitive enought to detect a 5sq m RCS at 200km, at wich distance can you detect a 0.01 sq m?

What would be the required power to detect the same 0.01sq m target using the same captor and antena at 200km?

What would be the required antena diameter to detect the same 0.01sq m target using the same captor and powerat at 200km?

This is only mathematic, very easy in fact, so you should not need any blob, signal smearing to find the answer... you dont even need the frequancy. but if you want it, lets say its a X-band.

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Hamilcar Ypu'v e just described a Zhuk. 10/17/2009 3:02:29 PM

Do your own math.

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Hamilcar You've just described a Zhuk. 10/17/2009 3:03:48 PM

Do your own math.

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Bluewings12 10/17/2009 3:19:08 PM

Redparadize to Hamilcar :

""About what bluewings12 said:

My 2 cents .

There is a noticeable difference in between tracking a VLO aircraft on radar and the capability of an EM missile seeker to get a lock and a track on the same VLO fighter .

Then , there are ECMs ...

I said:

your statement sound perfectly right to me

Your answer was:

Well, first, i didn't said it was accurate, and i don't think bluewings12 really wanted to be accurate. He didn't talk about any specific positioning or range. His statement is, tell me if i am wrong, is that knowing the average position of a plane doesn't mean that you can have a missile look and track on it. And thats not in contradiction with what you say above. By adding:"Then , there are ECMs ..." bluewings12 probably mean that, in regard of my scenario, even if you succeed to bring a IR missile close enoughs to look the raptor, he will still have his ECM. and thats also true.

What I said and what you did not inderstand was that he was trying to compare a rock to an orange. Neither concept had anything to do with each other. Some missiles (two) use active radar homing to redio-locate and chase (one) or intercept (other) an aircraft target. Most infra-red missiles chase. So when the poster commented, he introduced extraneous to the topic issues that have nothing to do with the discussion which is "Radar versus Stealth: Passive Radar and the Future of U.S. Military Power". Even at that he got it wrong. Whether VLO or not the dame mechanism that allowes the missile to enhahe rtemains constant. All signal management does is reduce the acquisition sensitivity threshhold detection of signal. The missile uses the same mechanism. I find it curiois that you would not understand that/.I said it plain enough twice.

Again, It was very difficult to follow you. If you don't mind I will comment it:""

------------------->

Well , to start with I meant that a radar driven missile (Amraam , Mica , R-27RE , R-37 , R-77 , Meteor , etc) will have a hard time to get a lock on a VLO platform by itself with its own radar . Unless to be directed to the target by other means , the missile 's aquisition range is very small . Again a VLO target , it 's much better to use IR missiles . DIRCM (Directed Infra Red Counter Mesure) is not really up to speed yet . To put it bluntly , a good IRST + TV + LRF + IR missile can kill a VLO target at 30-35km passively (bare the laser beam for ranging) . Without using the LRF , firing an IR missile from the hip against a VLO platform can be archive from as far as 50 to 80km , depending on the aircraft and capabilities .

Hamilcar , I don 't compare a rock to an orange (?) . It is you who is forgetting some known capabilities .

To be perfectly honest , I wouldn 't like to be a futur F-35 driver going against something like the SU-27 , SU-30 , SU-35 or Rafale . They all have the optical means , the IR detection and tracking means and the IR missiles to kill the F-35 BVR (you can 't see a F-35 with your own eyes at 30+ km) .

Now , a clever designed air defense with OTHR , VHF , UHF , Cell phones and TV based anti-stealth radars plus conventional radars and capable aircrafts can almost negate the VLO technology . France and the UK have one of the most secu

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RedParadize 10/17/2009 5:20:17 PM

To Hamilcar:

If you are not ready to do high school math, then you should not mess with the Doppler effect and blob algorithm. Specially when they are completely out of the subject.

If you have an opinion about this article and the general subject around it, feel free to share it with us. Without unneeded complex word or concept.

about the little math, it point out that even on the X-band, there is way to pick a LO at long range, trough the improvement of captor,software, emission power etc.

But a stronger emission have the annoying side effect of virtually placing a huge flashing neon sign on your ship that says: "LOOK AT ME! I'M HERE! SHOOT ME, SHOOT ME!!"

Hello Bluewing12

I think whe should stay concervative, after all, its all top secret technology. And there his alot of disinformation.

IRST and other focused IR detection device have a limited capacity to detect a plane, LO or not. Because it cant cover a large portion of the sky. But Once a plane is approximatively located. It does enhance the capacity to track a LO plane, specially at high altitude where the atmosphere is less dense. Keep in mind that when LO plane like the raptor lunch a missile, he have to open his bay. Greatly reducing his RCS.

I don't think the focused IR detection technology is fully mature. But its clearly a "must have" feature.

I have a quick anecdote about disinformation:

I dont remember exacly the year but it was around 1993, I was very exited because whe where lucky enought tho have a F-117 at the Quebec International Airshow. I had the oportunity to talk to the pilot. I asked how fast the plane was. of course he could not answer. Like a 13 kid, I quickly told him everything I knowed about my favorite plane of the time: the SR-71 Black bird, ya i was young lol. And The Pilot told me that the F-117 was even faster then the SR-71. After a quick look on the plane, i turn to him and said: its not possible, the plane is not aerodinamic enought! the pilot smiled and said "Are you sure?" I looked the plane again and start to wounder what i didnt know.

American Pilot: 1

Little Kid: 0

as you say:

Cheers

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