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F-35A in full loadout for first time

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And you should have read the entire doc.

Notice this...


It means the interrupted sampling method works best when the entire pulse train repeats itself with no changes in individual pulse characteristics.

Next, the technique requires two aircrafts, one to serve as the target and one as the jammer.


Look at fig 1 and see for yourself.

The target aircraft is irradiated and its echo-ed signals are captured by the escorting jammer, which then generate a supposedly countermeasure signal. And that is what the technique really mean. Not what SPECTRA supposedly does.

vDk81to.jpg


The word 'interrupted' does not mean SPECTRA can sample only 3 out of 5 and can replicate the remaining two. :lol:

You do what the Chinese does, which is that in your desperation to salvage your argument, you look only for keywords and interpret the source to fit your needs.

Welcome to reality. The Raffle is not what you tried -- in vain -- to make it out to be.

You missed the point as usual, nothing surprising. As the name suggests, it is for repeater jamming. The same concept can be used in many other settings. The paper itself is restricted to a very small aspect of ECM, that's why it is freely accessible. Active cancellation is naturally not repeater jamming, that's obvious.

But the fact that you somehow related this paper to the Rafale makes it a strawman argument as usual. Does it say anywhere that the Rafale is using this exact same technique?

I put up this paper to point out that your knowledge in this field is stuck in the 90s. You made the argument that ECM requires sampling, I pointed out that there is a technique called interrupted sampling as well.

You mean there is no memory in the Digital Radio Frequency Memory ( DRFM ) ? :lol:

Another strawman argument. Did I say the DRFM has no memory?

I pointed out that memory is not an issue today. You speak of it as a huge insurmountable problem when it is not.
 
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You missed the point as usual, nothing surprising. As the name suggests, it is for repeater jamming. The same concept can be used in many other settings. The paper itself is restricted to a very small aspect of ECM, that's why it is freely accessible. Active cancellation is naturally not repeater jamming, that's obvious.

But the fact that you somehow related this paper to the Rafale makes it a strawman argument as usual. Does it say anywhere that the Rafale is using this exact same technique?
If the Raffle does not use this technique, then you cannot use it to argue for the Raffle. Simple as that.

Further, it revealed that you do not have the background education and related experience. Exactly as I said, you searched for keywords but did not understand their proper contexts, so now you resort to the lame defense that the Raffle does not have to use the exact technique ?

Against tiers 2 and 3 adversaries, SPECTRA will probably succeed most of the time. But against the F-35, the Raffle is Dead-On-Arrival ( DOA ).

I put up this paper to point out that your knowledge in this field is stuck in the 90s. You made the argument that ECM requires sampling, I pointed out that there is a technique called interrupted sampling as well.
And you are wrong. The word 'interrupted' in that context is when the jammer placed itself between the target and the seeking radar, not that the sampling process itself was 'interrupted'. That technique is physical interruption.

FfDdFxU.gif


- The ground threat radar illuminates the target G.

- Target G becomes a radiator as expected.

- Jammer J is partially interposed between target G and ground threat radar.

- Jammer J collects some of the echoes from target G.

- Jammer J then create a countermeasure signal and sends it towards the ground threat radar.

That is exactly how the paper's authors explained it.

At best, the jammer may partially sampled the seeking radar's signal as well as sampled the echo-ed signals from the target, then made a 2+2 = 4 connection and create a countermeasure signal. But that is still different from what Dassault claimed for the Raffle.

Another strawman argument. Did I say the DRFM has no memory?

I pointed out that memory is not an issue today. You speak of it as a huge insurmountable problem when it is not.
And you are STILL wrong. You may not have said that DRFM has no memory, but the fact that you mocked me about it means you did not understand the full concept in the first place.

Currently, I am in the semiconductor industry, specifically NAND. Prior to NAND, I was employed by Micron Technology, one of the leading global memory manufacturers. I worked specifically in the 'Burn-In' dept, meaning temperature stress testing of DRAM memory modules. By mid 2018, I will be fully immersed in Intel's new 3D Crosspoint memory product line. So yes, I understand memory and its necessity very well.

You are still wrong in that memory is not very important. Everything can use more memory, whether it is the microwave oven or a Samsung smart refrigerator or a NASA rocket. So when you are talking about a pulse train of millions of pulses that have extreme complex characteristics, sampling becomes a vital issue.

To 'point out' something means you must have supporting evidence. All you did was declared.

Hitchen's Razor: "What can be asserted without evidence can be dismissed without evidence"
 
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I have been to Red Flag. How about you ? You raised your baseless suspicions about the exercise as rigged. So until you can find corroborating foreign pilots witnesses, you and he are in the same boat.

You want me to accept the validity of Red Flag because you say so? Or because X number of air forces participated who had no control over what data is being fed to the F-35? Sorry, this is not evidence enough for me. Now, read what I have already posted here:

https://defence.pk/pdf/threads/f-35a-in-full-loadout-for-first-time.511975/page-11#post-9800453

For me, what would be authentic is something akin to this for A2A:

http://www.combataircraft.net/2017/08/15/hill-f-35s-on-combat-hammer/

Otherwise you can keep harping on about the greatness of F-35, it still hasn't gone through OT for A2A.
 
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You want me to accept the validity of Red Flag because you say so? Or because X number of air forces participated who had no control over what data is being fed to the F-35? Sorry, this is not evidence enough for me. Now, read what I have already posted here:

https://defence.pk/pdf/threads/f-35a-in-full-loadout-for-first-time.511975/page-11#post-9800453

For me, what would be authentic is something akin to this for A2A:

http://www.combataircraft.net/2017/08/15/hill-f-35s-on-combat-hammer/

Otherwise you can keep harping on about the greatness of F-35, it still hasn't gone through OT for A2A.
And your criticisms about Red Flag in general, and the F-35 in particular, are not good enough, not just for me, but for legions of pilots, Americans and foreign, who have been to Red Flag, and found the exercise credible.

You can criticize the general idea of Red Flag all you want, but all it does is make you nothing more than a crybaby while every air force in the world wish they could have something at home even halfway close.

What we create in Red Flag is not open for approval by those who have or will never even touched an aircraft. Their opinions are meaningless and worthless. No matter what we do, we will at the end of their jabs anyway. They judge US by an unreasonable standard -- PERFECTION. So why should we care ?

Your acceptance of my arguments neither win or lose wars, but our combat successes speaks volumes on the efficacy of our training program, Red Flag or not. Of course, you can petition your politicians to refuse to deal with US because you have no evidence for A, B, or C, and so on, then in the event your country, whoever it maybe, loses a war against US, you can always comfort yourself that you were steadfast against the Americans no matter what. :enjoy:
 
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And your criticisms about Red Flag in general, and the F-35 in particular, are not good enough, not just for me, but for legions of pilots, Americans and foreign, who have been to Red Flag, and found the exercise credible.

You can criticize the general idea of Red Flag all you want, but all it does is make you nothing more than a crybaby while every air force in the world wish they could have something at home even halfway close.

What we create in Red Flag is not open for approval by those who have or will never even touched an aircraft. Their opinions are meaningless and worthless. No matter what we do, we will at the end of their jabs anyway. They judge US by an unreasonable standard -- PERFECTION. So why should we care ?

Your acceptance of my arguments neither win or lose wars, but our combat successes speaks volumes on the efficacy of our training program, Red Flag or not. Of course, you can petition your politicians to refuse to deal with US because you have no evidence for A, B, or C, and so on, then in the event your country, whoever it maybe, loses a war against US, you can always comfort yourself that you were steadfast against the Americans no matter what. :enjoy:

You are not getting my point. If the F-35 is fed information beyond its current capabilities, other airforces do get a very good practical experience of what it's like dealing with the final target capability of F-35. Meanwhile, without operational testing, you can keep making whatever tall claims you want. Your own testers have given a very damning initial assessment. Waiting to hear the results of next round.
 
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You are not getting my point. If the F-35 is fed information beyond its current capabilities, other airforces do get a very good practical experience of what it's like dealing with the final target capability of F-35. Meanwhile, without operational testing, you can keep making whatever tall claims you want. Your own testers have given a very damning initial assessment. Waiting to hear the results of next round.
There is no such 'feeding'. I do not know what the hell you are talking about. It is not as if the F-22/35 receives any kind of 'special treatment'.

Have you ever been involved in any kind of product R/D and testing ? From what I can tell, looks like not. Very seldom is any initial assessment is charitable. The F-35 is taking product development and testing in paths no one have the courage to go. So please spare US any criticism as if you know what you are talking about.

How many times are you people willing to be embarrassed, hm ? Did your Pakistan pioneered the fly-by-wire flight control system concept ? Air refueling ? IFF ? Ejection seat ? But here you are leveling baseless criticisms at US for trying new things.

I can damn near sense the great anguish thru the Internet. A great disturbance in the Force.

It is not enough that the Americans have the F-22, pretty much unchallenged or perhaps even unchallengeable in the sky. Now the Americans puts out the F-35. A close number two while the best of the rest of the world struggles to put out their firsts.

Intolerable -- says you people thru gritted teeth and bloodshot eyes. This is why you people latch onto and exaggerate every errors and mistakes we made as if such have never been seen before.

Just like climate change, the F-35 is settled. Let go Luke.
 
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Hitchen's Razor: "What can be asserted without evidence can be dismissed without evidence"

Hey, look, I actually learnt something from you. I didn't know this statement was Hitchen's razor.

You do realize this statement is another strawman tactic, right? 'Cause active cancellation exists. It's not about evidence, you just don't know it.
http://www.mwrf.com/systems/analyzing-active-cancellation-stealth

I think you should be using the Sagan Standard instead:
Extraordinary claims require extraordinary evidence.

Saying the Rafale's frontal RCS is that of a sparrow without relying on shaping is indeed an extraordinary claim. Unfortunately direct evidence isn't available, but indirect evidence is and more will be available in time.

In 2 or 3 years, we will know where the F-35 stands vis-a-vis the Rafale, even Gripen E. You can live in your bubble until then.

But, just so you are prepared to deal with the shock, here's an old air force evaluation anyway.
Dutch+cost+study.jpg

=========
http://www.dedefensa.org/article/to...pril-2002-the-road-to-chaos-and-the-dutch-way
A surprising and important detail had been made public: the technological and operational evaluation by the RNAF of the three candidates. According to the RNAF criteria, the JSF had been graded 6.97; the Rafale, 6.95; and the Eurofighter Typhoon, 5.85. This grading is surprising because it compares aircraft which seem only marginally comparable. The Rafale is beginning to enter into service; the Typhoon is in its terminal phase of development; and the JSF is a ''paper aircraft'', with only theoretical capabilities. The grading is also surprising because the JSF, placed on an almost equal footing with the Rafale, is far from being able to demonstrate the operational and technological superiority attributed to it.
=========

What next? You're gonna say you don't believe in actual air force evaluations?
 
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Hey, look, I actually learnt something from you.
You learned a lot from me.

Cause active cancellation exists. It's not about evidence, you just don't know it.
http://www.mwrf.com/systems/analyzing-active-cancellation-stealth
You talked as if you brought on something new. No, you have not.

Here...Back in '09...

https://defence.pk/pdf/threads/why-is-pakistan-not-purchasing-the-rafale.27367/page-7#post-393870

I was invited to this forum back in '09.

In 2 or 3 years, we will know where the F-35 stands vis-a-vis the Rafale, even Gripen E.
Then until that time, the appropriate thing to do is not to make equally extraordinary claims.

You can argue the same for US as well, but unfortunately for you, so far, the only country that have demonstrated its 'stealth' platforms worked is US -- the F-117. Right now, the Russians and the Syrians are finding out the hard way about the F-22 even though they have been silent about it. You would think that if they have been successfully tracking the F-22, youtube would have been inundated with such videos.

You can counter-argue that the Russians and the Chinese would not reveal that they can track the F-22 because they do not want the US to know they can, but that would be a silly counter-argument because if they can, then certainly we would know they can, so what is the point of keeping such capability a secret ? Let the world know the F-22 is not as the US hyped it out to be. And by extension, same goes for the F-35. Perhaps even put the F-35 out of contention for purchase by uncertain clients.

So in the end, so far only the US can make extraordinary claims and have people believe those claims. Or at least put high value on those claims.

You cannot say the same for the Raffle.

You can live in your bubble until then.

But, just so you are prepared to deal with the shock, here's an old air force evaluation anyway.

What next? You're gonna say you don't believe in actual air force evaluations?
That was in 2002. The F-35's first flight was 2006.
 
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You learned a lot from me.

:lol:

You are struggling to spell Rafale.

You talked as if you brought on something new. No, you have not.

Here...Back in '09...

https://defence.pk/pdf/threads/why-is-pakistan-not-purchasing-the-rafale.27367/page-7#post-393870

Yes, it's not new. The technology itself is as old as 1996. It's merely undergone a huge upgrade on the Rafale.

I was invited to this forum back in '09.

You do realize your joining date is right below your avatar right? Or you never noticed? :lol:

Then until that time, the appropriate thing to do is not to make equally extraordinary claims.

You forget that it wasn't I who made the claim. Scroll below for the video.

You can argue the same for US as well, but unfortunately for you, so far, the only country that have demonstrated its 'stealth' platforms worked is US -- the F-117. Right now, the Russians and the Syrians are finding out the hard way about the F-22 even though they have been silent about it. You would think that if they have been successfully tracking the F-22, youtube would have been inundated with such videos.

You can counter-argue that the Russians and the Chinese would not reveal that they can track the F-22 because they do not want the US to know they can, but that would be a silly counter-argument because if they can, then certainly we would know they can, so what is the point of keeping such capability a secret ?

Let the world know the F-22 is not as the US hyped it out to be. And by extension, same goes for the F-35. Perhaps even put the F-35 out of contention for purchase by uncertain clients.

Ridiculous. Again. Now you are using strawman arguments for countries.

If they successfully detected and tracked the F-22 from a distance, they would keep it secret. You don't advertise the fact that you have successfully compromised your enemy's best asset. Rather you encourage its proliferation. This is psyops 101. Even kids know this.

And why will they bother to help rule the F-35 out of contention for other American clients, it doesn't really affect them. If Canada or Australia decide not to purchase the F-35, then it's not like the market will open up for Russia or China. There is no monetary gain there. American allies will simply buy a different western jet.

If they advertise this, then the US will go into an overdrive to modernize the F-22 ASAP. Perhaps start a new aircraft development much earlier than planned. This is counterproductive to both Russia and China.

What will prove the capability of the F-35 is its performance in foreign tenders, like Belgium and Finland, perhaps Canada against similarly equipped 4.5th gen aircraft.

So in the end, so far only the US can make extraordinary claims and have people believe those claims. Or at least put high value on those claims.

Is that why the Israelis refer to the F-35's design as "OK"?
“We think the stealth protection will be good for 5-10 years, but the aircraft will be in service for 30-40 years, so we need EW capabilities [on the F-35] that can be rapidly improved,” a senior Israeli air force (IAF) official tells Aviation Week. “The basic F-35 design is OK. We can make do with adding integrated software.”

:lol: Apparently, the F-35's stealth is only good for 5-10 years even back in 2012.

You cannot say the same for the Raffle.

As usual you are wrong again.

At 11' 20" Bruno Revellin Falcoz (who is presented before in the Video and who I know personally because he was technical head of Dassault during the time I was head of the ATL2 weapon system) say:

Bien sur nous somme dans des domaines un peu confidentiel, mais disons que la signature vue par l'avant d'un Rafale c'est la signature d'un moineau.

Translation:
Of course we are in areas somewhat confidential, but we can say that the front view signature of a Rafale is the signature of a sparrow.


This is pretty much an official declaration from Dassault. They have openly said the Rafale's frontal RCS is that of a sparrow. The USAF's going to be shocked when they bring in operational F-35 units to France for exercises.

That was in 2002. The F-35's first flight was 2006.

So what? The evaluations were based on a Paper-35 with perfect specs vs a flying Rafale with real world specs. And since 2002, the Rafale has only improved a lot with many new technologies that were not part of the evaluations while the F-35 is stuck in development since years and has not seen any major hardware upgrade since then even on paper.

Now the Rafale is undergoing development for a slew of new upgrades which will take it waaaaaaaaay past the F-35's basic hardware.
 
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:lol:

You are struggling to spell Rafale.
I made fun of the name. Look up the English word 'raffle'. Like whenever an Indian made ridiculous claims for the Brahmos, I called 'Brahless'. Get it ?

Yes, it's not new. The technology itself is as old as 1996. It's merely undergone a huge upgrade on the Rafale.

You do realize your joining date is right below your avatar right? Or you never noticed?
Yeah...It just goes to show you that YOU brought on nothing new. Not that the claims are new, but that you tried to make it as if no one ever heard of it before.

If they successfully detected and tracked the F-22 from a distance, they would keep it secret. You don't advertise the fact that you have successfully compromised your enemy's best asset. Rather you encourage its proliferation. This is psyops 101. Even kids know this.
Unfortunately, we are not kids. We have been at this game far longer than anyone in the world.

If the Russians and/or Chinese somehow managed to detect the F-22 over Syria, definitely we would know about it by way of behaviors, specifically, radar behaviors as indicated by the F-22's RWR system. It would not matter if they let the world knows it because we would develop new tactics to counter.

:lol: Apparently, the F-35's stealth is only good for 5-10 years even back in 2012.
Is that why your India is discarding its dream for a 'stealth' fighter ?

Wait...India is not...:lol:

As usual you are wrong again.
No, I am not wrong. Whatever Dassault claimed, just like our claims for the F-35, it is up to debate. So until the Raffle is exposed to combat, the way you guys insisted, I am not wrong.

It is funny that for the F-35, you insists on all doubts, despite the fact that the US now have three functional 'stealth' platforms, but for the Raffle, you chose to take Dassault's words at face value.
 
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Mr. random brought on the Raffle and its SPECTRA ECM suite as the matching solution for shaping for 'stealth'. The claim here is that SPECTRA can create 'active cancellation' which imply a pulse-to-pulse cancellation. In order to do this, except for phase, the counter-pulse must match the seeking-pulse in everything else regarding pulse characteristics.

It sounds reasonable enough until the claim is drilled down into the technical details.

The dispute here is that SPECTRA does not have to read every pulse in order to create the counter-pulses. The supporting argument is the concept called 'interrupted sampling repeater jamming' ( ISRJ ) technique. This is wrong.

The core of the misunderstanding lies in terminology, or rather the lack of knowledge of what words and phrases means in their proper technical contexts.

In Electronics Warfare ( EW ), to 'jam' a seeking ( threat ) radar is not to cancel out its transmitted pulses at the point of skin contact which produces echoes. The correct context of the word 'jam' is to confuse. The most popular form of confusion is misdirection, aka 'misleading'. To cancel a transmitted pulse, meaning to somehow destroy the echo, is not misleading the threat radar.

If the threat radar sees one target, that is not misdirection.

If the threat radar sees no target, that is not misdirection.

But if the threat radar sees two targets, is that misdirection ? No, it is not.

As far as the threat radar is concerned, there are two legitimate targets. What is misdirection for the threat radar, or misleading the threat radar, is from the jammer's perspective. In other words, if the jamming signal is good enough, the threat radar will work as it was designed to do and display two targets. For the jammer, there is only one target -- itself.

FeZCnz4.jpg


In conventional jamming technique, the ECM system will memorize the entire pulse train, which in the above example consists of two pulses. The ECM system will replicate the pulses regarding their characteristics but out of phase. Then after a certain amount of time, the ECM system will transmit these signals to the threat radar. Depending on the delay time, the threat radar will see either one target or two targets.

The jammer is located at 10 km, but the threat radar sees 10.5 km. For the jammer, that is misleading, but for the threat radar, there is a legitimate target at 10.5 km. No misdirection.

The jammer is located at 10 km, but the threat radar sees two targets, one at 10 km and one at 10.5 km. For the jammer, that is misleading, but for the threat radar, there are two legitimate targets. It is up to the operator to determine which is the true target. The operator may have been informed by another source that there is only one target, but the radar is telling him there are two. This is the confusion that is the goal of most jamming techniques. Whether other target components such as speed, altitude, or Doppler, are exploited by the ECM and transmit to the threat radar, the confusion will be matched. There are two targets at 10 and 10.5 km ranges. Or there are two targets approaching at 100 km/h and 150 km/h speed. No matter which, in order to confuse the operator ( not the radar ), there must be multiple targets.

FxpqVA9.jpg


But what happens if the threat radar is sophisticated enough to alter pulse characteristics like the example above ? There are five pulses in that train and each pulse is unique. By the time the ECM system memorized all five pulses and create five counter-pulses, it will be too late as inevitably more than one pulse will have produce echoes and returned to the threat radar.

Now comes the jamming technique of 'interrupted sampling repeater jamming' ( ISRJ ). Crucial to ISRJ is high speed processing and high memory allocation.

The ECM system memorized pulse 1 and create a counter-pulse. The jammer will be painted by pulse 2 during that period of interruption. The ECM system memorized pulse 3 and create a counter-pulse. The jammer will be painted by pulse 4. And so on...

Depending on system capabilities, it is possible for the ECM system to match pulse-for-pulse for a short time. If the threat pulse train is predictable enough, meaning there is repeating pattern, the jammer's ECM suite will memorize the entire chain and create an advantage the threat radar's operator cannot overcome.

But this is not 'active cancellation'.

In theory, if a pulse can be memorized and a slightly altered counter-pulse is produced, that pulse can be cancelled out by a perfectly matching counter-pulse that is out of phase.

A Tier 1 threat radar, especially in the form of a multi-beams AESA array, will not allow this to occur. A Tier 1 threat radar can produce pulse trains that will include continuous-wave duration to force any ECM, including those with digital radio freq memory ( DRFM ) capability, to expend vital resources to memorize that period of CW transmission, thereby making the target visible on the subsequent pulses and pulse trains.

Remember, this is active cancellation, meaning the threat radar must see NO echoes. SPECTRA may get lucky and cancel out pulses 1 and 2, but if the threat radar sees pulse 3's echo, it will display that one echo. Deception jamming ( DECM ) is where the threat radar sees two or more echoes from one pulse. Active cancellation, assuming successful, produce no echoes.

So realistically, SPECTRA can be useful in at least two ways against Tiers 2 and 3 threat radars. Engage DECM as escort. And engage active cancellation in penetration missions.

But SPECTRA will not be effective against Tier One threat radars.
 
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I made fun of the name. Look up the English word 'raffle'. Like whenever an Indian made ridiculous claims for the Brahmos, I called 'Brahless'. Get it ?

Yes, you are a child. There's no need to explain why you are one, it was evident.

Unfortunately, we are not kids. We have been at this game far longer than anyone in the world.

If the Russians and/or Chinese somehow managed to detect the F-22 over Syria, definitely we would know about it by way of behaviors, specifically, radar behaviors as indicated by the F-22's RWR system. It would not matter if they let the world knows it because we would develop new tactics to counter.

It is very likely that this has already happened but is still considered classified by both sides. So 'you' wouldn't know, the USAF would know. They probably didn't bother to tell you.

Considering the USAF believes the F-22 and F-35 are going to be useless after 2030, there is merit in that thought. Buy all the compromised jets with no other alternate qualities you want until then.

Did you forget that the CNO of the USN claimed that stealth is overrated?
http://www.businessinsider.in/A-top...ilities-is-overrated/articleshow/46191833.cms

Is that why your India is discarding its dream for a 'stealth' fighter ?

Wait...India is not...:lol:

No. India is not relying on shaping alone. I always said shaping based stealth is dying. Our industry pointed out that only 40-60% of the AMCA's stealth will come using passive methods.

No, I am not wrong. Whatever Dassault claimed, just like our claims for the F-35, it is up to debate. So until the Raffle is exposed to combat, the way you guys insisted, I am not wrong.

It is funny that for the F-35, you insists on all doubts, despite the fact that the US now have three functional 'stealth' platforms, but for the Raffle, you chose to take Dassault's words at face value.

:lol:

We all know active cancellation exists. At least that's been established.

Dassault claimed Rafale's frontal RCS is that of a sparrow.

India's Air Marshal said the Rafale has stealth features.

So how has this been taken at face value?
 
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Mr. random brought on the Raffle and its SPECTRA ECM suite as the matching solution for shaping for 'stealth'. The claim here is that SPECTRA can create 'active cancellation' which imply a pulse-to-pulse cancellation. In order to do this, except for phase, the counter-pulse must match the seeking-pulse in everything else regarding pulse characteristics.

It sounds reasonable enough until the claim is drilled down into the technical details.

The dispute here is that SPECTRA does not have to read every pulse in order to create the counter-pulses. The supporting argument is the concept called 'interrupted sampling repeater jamming' ( ISRJ ) technique. This is wrong.

The core of the misunderstanding lies in terminology, or rather the lack of knowledge of what words and phrases means in their proper technical contexts.

In Electronics Warfare ( EW ), to 'jam' a seeking ( threat ) radar is not to cancel out its transmitted pulses at the point of skin contact which produces echoes. The correct context of the word 'jam' is to confuse. The most popular form of confusion is misdirection, aka 'misleading'. To cancel a transmitted pulse, meaning to somehow destroy the echo, is not misleading the threat radar.

If the threat radar sees one target, that is not misdirection.

If the threat radar sees no target, that is not misdirection.

But if the threat radar sees two targets, is that misdirection ? No, it is not.

As far as the threat radar is concerned, there are two legitimate targets. What is misdirection for the threat radar, or misleading the threat radar, is from the jammer's perspective. In other words, if the jamming signal is good enough, the threat radar will work as it was designed to do and display two targets. For the jammer, there is only one target -- itself.

FeZCnz4.jpg


In conventional jamming technique, the ECM system will memorize the entire pulse train, which in the above example consists of two pulses. The ECM system will replicate the pulses regarding their characteristics but out of phase. Then after a certain amount of time, the ECM system will transmit these signals to the threat radar. Depending on the delay time, the threat radar will see either one target or two targets.

The jammer is located at 10 km, but the threat radar sees 10.5 km. For the jammer, that is misleading, but for the threat radar, there is a legitimate target at 10.5 km. No misdirection.

The jammer is located at 10 km, but the threat radar sees two targets, one at 10 km and one at 10.5 km. For the jammer, that is misleading, but for the threat radar, there are two legitimate targets. It is up to the operator to determine which is the true target. The operator may have been informed by another source that there is only one target, but the radar is telling him there are two. This is the confusion that is the goal of most jamming techniques. Whether other target components such as speed, altitude, or Doppler, are exploited by the ECM and transmit to the threat radar, the confusion will be matched. There are two targets at 10 and 10.5 km ranges. Or there are two targets approaching at 100 km/h and 150 km/h speed. No matter which, in order to confuse the operator ( not the radar ), there must be multiple targets.

FxpqVA9.jpg


But what happens if the threat radar is sophisticated enough to alter pulse characteristics like the example above ? There are five pulses in that train and each pulse is unique. By the time the ECM system memorized all five pulses and create five counter-pulses, it will be too late as inevitably more than one pulse will have produce echoes and returned to the threat radar.

Now comes the jamming technique of 'interrupted sampling repeater jamming' ( ISRJ ). Crucial to ISRJ is high speed processing and high memory allocation.

The ECM system memorized pulse 1 and create a counter-pulse. The jammer will be painted by pulse 2 during that period of interruption. The ECM system memorized pulse 3 and create a counter-pulse. The jammer will be painted by pulse 4. And so on...

Depending on system capabilities, it is possible for the ECM system to match pulse-for-pulse for a short time. If the threat pulse train is predictable enough, meaning there is repeating pattern, the jammer's ECM suite will memorize the entire chain and create an advantage the threat radar's operator cannot overcome.

But this is not 'active cancellation'.

In theory, if a pulse can be memorized and a slightly altered counter-pulse is produced, that pulse can be cancelled out by a perfectly matching counter-pulse that is out of phase.

A Tier 1 threat radar, especially in the form of a multi-beams AESA array, will not allow this to occur. A Tier 1 threat radar can produce pulse trains that will include continuous-wave duration to force any ECM, including those with digital radio freq memory ( DRFM ) capability, to expend vital resources to memorize that period of CW transmission, thereby making the target visible on the subsequent pulses and pulse trains.

Remember, this is active cancellation, meaning the threat radar must see NO echoes. SPECTRA may get lucky and cancel out pulses 1 and 2, but if the threat radar sees pulse 3's echo, it will display that one echo. Deception jamming ( DECM ) is where the threat radar sees two or more echoes from one pulse. Active cancellation, assuming successful, produce no echoes.

So realistically, SPECTRA can be useful in at least two ways against Tiers 2 and 3 threat radars. Engage DECM as escort. And engage active cancellation in penetration missions.

But SPECTRA will not be effective against Tier One threat radars.

:lol: My, how the tables have turned.

Now you are willing to believe what I've always said, that the system can react to single pulses.

A Tier 1 threat radar, especially in the form of a multi-beams AESA array, will not allow this to occur.

Nope. It's easy to defeat this. At least the Spectra can.

The radars on the F-22 and F-35 are analog. At any one time one T/R module is only producing 1 beam. So if the radar has 1500-2000 modules, the radar is producing only that many beams.

But realistically, you would use an entire section of a radar for long range detection, not single T/R modules. So if you choreograph the radar to use up half as many T/R modules for detection of air threats and the rest for other purposes, then you have all 1000 T/R modules trying to detect air threats at the same frequency and power settings. As far as Spectra is concerned, that's only 1 threat.

You could further divide the 1000 modules to cater to different regions in space, different signal settings and so on. But to Spectra that's just a few more threats. So at any one time it only has to deal with a few threats. The short hang time of AESA radars means that Spectra is exposed to radar signals only for a brief period. As I said before, Spectra is meant to deal with multiple threats, could be dozens at a time. Even the old Spectra from over 20 years ago could simultaneously process tens of thousands of different signals in real time.

Your current radar is now a tier 2 radar. Give it a year or two and the LCA will be flying with a radar that's more advanced than the ones on the F-22 and the F-35. The F-22 will get a similar radar after 2025 and the F-35 has not been planned for the upgrade yet. In other words, Spectra uses higher tier hardware compared to what's on the F-22 and F-35.

Btw, there is no such thing as an ideal system. Spectra doesn't have to cancel out an echo every single time. It only has to perform enough so the radar can reject a compromised return as a false positive, especially using nap of the earth flying.
 
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