MMRCA 2.0 - Updates and Discussions

[Nikhil]

@vstol Jockey @Ashwin @Nikhil is it possible for spectra to acheive active cancellations against an aesa radar?

There was discussion on this started by @BMD here's the link...

Why active cancellation vs stealth is a myth

• US approach is pure stealth...why?

. US stealth technology is strictly a real time approach. It is based off of shaping and absorbent properties of materials. The RF energy emitted by a radar system is a form of electromagnetic energy. It has an electric field component and a magnetic field component. With conductive absorbers the electric part of the field interacts with the electric field within the absorber material, altering it, which imparts kinetic energy to the conductive particles which is then dissipated as heat. With magnetic absorbers it is the same thing, only interactions between the magnetic fields. Since it is electric field-electric field or magnetic field-magnetic field interactions they happen at the speed of light and so are instantaneous - real time. And there is a particular type of absorber that the French are trying to mimic - one which reflects the non-absorbed portion with a 180 degrees phase shift.

French approach...

.But the French have a problem since they are trying to use *electronic warfare*. Electrons in a conductor travel very fast, but they do not travel at the speed of light. Thus, the electronic processing is not instantaneous. And thus you cannot use a full real time approach to achieve full cancellation (you would always be reacting to events with lag). But engineers know how to cheat!! A phase shift is the same thing as a time delay. To cancel the reflected signal all you have to do is calculate a good time to start emitting the exact same signal! The time you choose will be such that the two signals (reflected and yours) are 180 degrees out of phase and thus cancel one another. So their system simply needs to first analyze the incident radar signal and determine what it is, pull characteristics of it out of memory, and then do some final processing to account for attenuation of the reflected wave, doppler effect and such (the time needed for these calculations are also precalculated and used for the final phase shift). Then you start transmitting. A proper radar return is sent back while the upfront analysis is being done but after that - practically nothing. And if it shows up for a frame or two it won't really matter.

. There are other strategies, such as generating signals that will encompass or be higher than the echo from the aircraft, so that the radar threat will receive a signal that will mask the echo from the aircraft. Instead of creating a false echo and drawing the radar to the wrong place, the idea is to produce a signal that will mask the echo of the aircraft, so the radar will be unable to detect the aircraft Spectra is protecting .

.
So there are some differences between US and French technologies.

1) Theirs is only as good as the intelligence put into the mission file. If you guess wrong on what threats you might find then they might not have the proper characteristics stored in memory.

2) Electronics still takes time to process information. If you light up a US stealth aircraft with 20 radars it doesn't matter. The shaping and absorbers instantaneously reacts with all of them. The French system will have to process them a little at a time and will (at some point) be overwhelmed.

3) US tech is fine against unknown radars; the French tech isn't.

as mentioned above there is a massive problem using EW as a substitute for stealth. problem will be 100 folds against a frequency hopping AESA like the one on F 22 & F 35. If you don't know the frequency hopping pattern... it's basically game over. So how to deal with this problem ?

as @Picdelamirand-oil said... technique that seems to be used is to make a kind of adaptive mirror.

it's a mirror that can amplify or attenuate the received signal according to the known signature of the Rafale and the geometry of the threat in relation to the aircraft. This adaptation is real time but it doesn't change in micro-seconds, it's the "reflection" on this mirror that implements these extremely short times.

i have a doubt about this technique but
Electronic warfare is a closely guarded secret. There are many thing we don't know....but US move purely towards shaping and absorbent properties of materials to achieve stealth & not EW tell you something.

• Spectra capability from brochure.

SPECTRA uses "active cancellation" technology , with the jamming transmitters picking up a hostile radar and then feeding back the signals out-of-phase to cancel out the echo from the aircraft. Active cancellation, a unique EW technique that locates an enemy radar in range and bearing, calculates the scatter that it will receive from the Rafale, and transmits an exact mimic of the aircraft’s actual echo, but one-half wavelength out of phase, so that the radar sees nothing.

Using sophisticated techniques, such as interferometry for high precision DOA and passive ranging, digital frequency memory for signal coherency and active phased-array transmitters for maximum effectiveness and covertness, the highly advanced multi-sensors and artificial intelligence data fusion capabilities of SPECTRA provide the Rafale aircraft with the best chance to survive in harsh and lethal environments

.
DECM : Three AESA antennas on the fin root and canard roots based on DRFM ( Digital Radio Frequency Memory ) with pencil thin jamming beams. Can operate in offensive, defensive and stealthy modes.

. DBEM : Electromagnetic Detection and Interference - RWR/ECM ( Radar Warning Receiver / Electronic Counter Measures ) : Comprises of programmable threat libaries, ELINT/SIGINT functions and fully fused with other on and off board sensor data

• Specifications >

Interferometry (azimuth & elevation) with stated <1 deg bearing accuracy.

•2-40 GHz frequency coverage and lower end coverage ~200 MHz

•Geolocation of emitters
~250 km detection range (dependent on the emitter).

Target coordination generation for weapons employment.

Now india has bought F3R standard rafale with improvement in spectra & what were those improvements ?

• advanced electromagnetic detection capability based on new digital wide-band-receiver technologies, improving the suite’s spectrum analysis as well as its instantaneous interception capability.

• Thales upgraded Spectra’s solid-state jamming subsystem, which was one of the first to use electronically steered phased-array antennas. Carrara says for F3R, Spectra will include more powerful antenna.

these upgrade were done keeping AESA threat in mind. So it may all be true.

 

[A Person]

If Airbus is so awesome why is the Typhoon such a Trainwreck of a project

The Typhoon is a joint project between Airbus, Bae, and Leonardo. All four countries tried to use it as a way to develop the technologies where they were weak, so everyone got to do what they were the least qualified to do, so as to catch up at the expenses of the others.

There isn't any such issue for Airbus's own internal projects, where it does not need to follow political demands for who does which part and can instead select on the basis of competency.

And does Airbus have an comparable aircraft to the f15ex??

Airbus doesn't, but Dassault does: it's the Rafale.

Yeah and still nothing close to the apg 77 and apg 81.

Sez you. I believe the RBE2-AA matches the performances of the APG-81.

The f22 and f35 will dominate every aircraft on the European mainland.

The F-22 has been much hyped, yes, but it's not without its own drawbacks. The program was cut down for cost and that has prevented it from getting to the numbers the USAF needed, and that makes it harder for it to get the funding it needs for upgrades. The F-35 is a complete shitshow, which was overpromised and underdelivered on everything (except LM's profit margin). And besides, you're not talking about the F-22 or F-35 here, but about the F-15, an aircraft whose design dates to the F-X program of 1965. Yeah it has had updates since, and the EX is an evolution of the Strike Eagle from the eighties. But it still has an airframe design with the rectangle air intakes and parallel fins at a right angle with the wings, that makes it a bitch and a half to try to mask from radars. It makes no sense to want this aircraft out of its supposed performances. The only possible reason to want it is to buy American protection. Is that a choice that India can afford to make, given how flimsy this protection looks nowadays?

 

[Picdelamirand-oil]

Yeas exactly, that's what i am.also doubting. And even our planned uttam rad have around 16 modes of scanning, ifear AI also will not come in handy if pilot manually changes the the mod.

A modern radar that is LPI must be able to recognize its signal despite the noise. For this purpose it keeps a replica of the signal and correlates it with what the receiver detects in order to know the direction and distance to the target.

So it is not necessary to completely destroy the return signal for the radar to be lost, it is enough to alter this signal so that the correlation does not work. What makes the originality of the French approach is our ability to analyze extremely quickly the received signals even if they are spread out in time or in frequencies and to alter them in real time enough so that the opposing radar does not detect anything.

This capability is unique in the world : it was tried by the Americans for the B2 but they failed, it seems to be an objective now for the Typhoon and probably for the future American planes.

 

[Nikhil]

A modern radar that is LPI must be able to recognize its signal despite the noise. For this purpose it keeps a replica of the signal and correlates it with what the receiver detects in order to know the direction and distance to the target.

So it is not necessary to completely destroy the return signal for the radar to be lost, it is enough to alter this signal so that the correlation does not work. What makes the originality of the French approach is our ability to analyze extremely quickly the received signals even if they are spread out in time or in frequencies and to alter them in real time enough so that the opposing radar does not detect anything.

This capability is unique in the world : it was tried by the Americans for the B2 but they failed, it seems to be an objective now for the Typhoon and probably for the future American planes.

analyzing receiving signal in real time that to of modern AESA ? Does speed of electrons work differently in France ? & What does this adaptive mirror technique you talk about ? Even that will require some time to analyze which doesn't make it instantaneous....ok here's the question let's say 1 rafale went up against 10 fighters with modern frequency hopping AESA like AN/APG 81 & 77(v)1, without it having any prior knowledge of there frequency hopping pattern, or anything else about the radar it's facing .

• Now would rafale be able to analyze signal from those 10 frequency hopping AESA in different pattern all in real time & fool them all at the same time without any prior knowledge ?.... don't think so.
you need something like quantum computing to achieve that.....even than it might not be possible.
This problem was realised by the Americans & that's why they went to shaping & using absorbing material to achieve true stealth. since no matter what type of radar or technique adversary use.
The shaping and absorbers instantaneously reacts with electromagnetic component at the speed of light.
• The French system on the other hand will have to process it all a little at a time and will (at some point) be overwhelmed.

• US tech is fine against unknown radars...the French tech isn't.

 

[Picdelamirand-oil]

analyzing receiving signal in real time that to of modern AESA ? Does speed of electrons work differently in France ? & What does this adaptive mirror technique you talk about ? Even that will require some time to analyze which doesn't make it instantaneous....ok here's the question let's say 1 rafale went up against 10 fighters with modern frequency hopping AESA like AN/APG 81 & 77(v)1, without it having any prior knowledge of there frequency hopping pattern, or anything else about the radar it's facing .

• Now would rafale be able to analyze signal from those 10 frequency hopping AESA in different pattern all in real time & fool them all at the same time without any prior knowledge ?.... don't think so.
you need something like quantum computing to achieve that.....even than it might not be possible.
This problem was realised by the Americans & that's why they went to shaping & using absorbing material to achieve true stealth. since no matter what type of radar or technique adversary use.
The shaping and absorbers instantaneously reacts with electromagnetic component at the speed of light.
• The French system on the other hand will have to process it all a little at a time and will (at some point) be overwhelmed.

• US tech is fine against unknown radars...the French tech isn't.

We don't need to analyse the signal we just have to recognise that there is a radar signal to present the "adaptative mirror" to it. The adaptative mirror is ready because it doesn't depend on the signal but only on the signature of the Rafale, it's course and orientation, and the localisation of the ennemi radar. It's the receive signal which is send to the ennemi radar after reflexion on the "adaptative mirror" without analysis. The analysis when done is a separate process from the active cancellation which is done at long distance to classify the radar as "ennemi".
And yes we are abble to prepare more than 10 "Adaptative mirror"!

 

[Hydra]

There was discussion on this started by @BMD here's the link...

Why active cancellation vs stealth is a myth

• US approach is pure stealth...why?



View attachment 17145

French approach...

This is thin film principle, but again its a frequency dependent one ( exactly speaking wavelength ). There is a relationship exist between thickness of the film and impending wavelength. I have studied it in my Bachelor degree classes some 15 years back. I forgot the derivation now. But one thing i am certain that its highly dependent on wavelength.

 

[Nikhil]

We don't need to analyse the signal we just have to recognise that there is a radar signal to present the "adaptative mirror" to it. The adaptative mirror is ready because it doesn't depend on the signal but only on the signature of the Rafale, it's course and orientation, and the localisation of the ennemi radar. It's the receive signal which is send to the ennemi radar after reflexion on the "adaptative mirror" without analysis. The analysis when done is a separate process from the active cancellation which is done at long distance to classify the radar as "ennemi".
And yes we are abble to prepare more than 10 "Adaptative mirror"!

so the adaptive mirror has every possible information regarding rafale own signature, deflection angle of radio waves at any give position in space & time....is that what you telling me ?

 

[Picdelamirand-oil]

There was discussion on this started by @BMD here's the link...

Why active cancellation vs stealth is a myth

• US approach is pure stealth...why?

Curiously @BMD has stopped arguing in this topic since Eurofighter announced a digital stealth capability.

Eurofighter Typhoon - Updates and Discussions

It's normally called an exciter signal though. I was being facetious. You don't have to try being facetious . You're a natural.

www.strategicfront.org

 

[Picdelamirand-oil]

so the adaptive mirror has every possible information regarding rafale own signature, deflection angle of radio waves at any give position in space & time....is that what you telling me ?

Yes, we built a giant anechoic chamber so we could measure all that, and the entire Rafale passes through that chamber every time we integrate a new load...

 

[vstol Jockey]

analyzing receiving signal in real time that to of modern AESA ? Does speed of electrons work differently in France ? & What does this adaptive mirror technique you talk about ? Even that will require some time to analyze which doesn't make it instantaneous....ok here's the question let's say 1 rafale went up against 10 fighters with modern frequency hopping AESA like AN/APG 81 & 77(v)1, without it having any prior knowledge of there frequency hopping pattern, or anything else about the radar it's facing .

• Now would rafale be able to analyze signal from those 10 frequency hopping AESA in different pattern all in real time & fool them all at the same time without any prior knowledge ?.... don't think so.
you need something like quantum computing to achieve that.....even than it might not be possible.
This problem was realised by the Americans & that's why they went to shaping & using absorbing material to achieve true stealth. since no matter what type of radar or technique adversary use.
The shaping and absorbers instantaneously reacts with electromagnetic component at the speed of light.
• The French system on the other hand will have to process it all a little at a time and will (at some point) be overwhelmed.

• US tech is fine against unknown radars...the French tech isn't.

Excellent. This is what has been my thinking also all along. You were not part of the older forum where I had such discussions with @Picdelamirand-oil. I had stated exactly the same. There is one more very serious flaw also partly pointed by you. HOW MANY RADARS CAN SPECTRA JAM AT THE SAME TIME? What is the duty cycle of the Spectra jammers when faced with multiple type of radars with varying transmission power? When the aircraft is illuminated by more than one radar, how will the jammers workand how many can they jam simultaneously? What will be the delay in responding to each frequency when the aircraft is overcome with multiple radars which are also changing their frequency at the speed of light? Russians shot down an Israeli F-16 using the same overwhelming jamming and multiple missile launch to fool the jammers of that formation. I have used the word formation. They launched multiple low level attack and high altitude attack missiles and the Israeli F-16 was cooked by the high top attack missile. I had long back stated to my French members that the Spectra will analysie and address the most potent threat and work to neutralise it. In case of A2A battle, it will work to fool the incoming missile. I was never convinced about its stealth capability nor do I believe in it today. I have always maintained that Rafale is an excellent aircraft and Spectra is the best best ASPJ in the world. But calling it stealth enhancing is stupid. Even in Libya campaign as stated by French themselves to their parliament, Rafale was picked up by the old radars of Libyan AF and targeted but were able to save themselves due to Spectra which fooled the incoming missiles. AND that French AF needed true SEAD/DEAD capability which was available only to USAF/USN at that time.

We don't need to analyse the signal we just have to recognise that there is a radar signal to present the "adaptative mirror" to it. The adaptative mirror is ready because it doesn't depend on the signal but only on the signature of the Rafale, it's course and orientation, and the localisation of the ennemi radar. It's the receive signal which is send to the ennemi radar after reflexion on the "adaptative mirror" without analysis. The analysis when done is a separate process from the active cancellation which is done at long distance to classify the radar as "ennemi".
And yes we are abble to prepare more than 10 "Adaptative mirror"!

Can Spectra handle unlimited number of radars which are frequency hopping at the sametime? It will be like dealing with billions of radars at the sametime. Stealth can only be done by shaping, shaping, shaping and RAS. Everything else is bullshit if we talk of stealth. Rafale is not a stealthy design.

 

[Nikhil]

Excellent. This is what has been my thinking also all along. You were not part of the older forum where I had such discussions with @Picdelamirand-oil. I had stated exactly the same. There is one more very serious flaw also partly pointed by you. HOW MANY RADARS CAN SPECTRA JAM AT THE SAME TIME? What is the duty cycle of the Spectra jammers when faced with multiple type of radars with varying transmission power? When the aircraft is illuminated by more than one radar, how will the jammers workand how many can they jam simultaneously? What will be the delay in responding to each frequency when the aircraft is overcome with multiple radars which are also changing their frequency at the speed of light? Russians shot down an Israeli F-16 using the same overwhelming jamming and multiple missile launch to fool the jammers of that formation. I have used the word formation. They launched multiple low level attack and high altitude attack missiles and the Israeli F-16 was cooked by the high top attack missile. I had long back stated to my French members that the Spectra will analysie and address the most potent threat and work to neutralise it. In case of A2A battle, it will work to fool the incoming missile. I was never convinced about its stealth capability nor do I believe in it today. I have always maintained that Rafale is an excellent aircraft and Spectra is the best best ASPJ in the world. But calling it stealth enhancing is stupid. Even in Libya campaign as stated by French themselves to their parliament, Rafale was picked up by the old radars of Libyan AF and targeted but were able to save themselves due to Spectra which fooled the incoming missiles. AND that French AF needed true SEAD/DEAD capability which was available only to USAF/USN at that time.


Can Spectra handle unlimited number of radars at the sametime? Stealth can only be done by shaping, shaping, shaping and RAS. Everything else is bullshit if we talk of stealth. Rafale is not a stealthy design.

If adaptive mirror technique as described by @Picdelamirand-oil do exist than sky is the limit. there is basically know need to analyze anything in real time. I hope what he say is true....than even the most modern AESA, multiple AESA can be tackled simultaneously.

 

[suryakiran]

If adaptive mirror technique as described by @Picdelamirand-oil do exist than sky is the limit. there is basically know need to analyze anything in real time. I hope what he say is true....than even the most modern AESA, multiple AESA can be tackled simultaneously.

The difference, I think with a very very rudimentary understanding is as follows. You and vstol are talking about jamming. Piced is not. He is talking about another approach.

 

[vstol Jockey]

If adaptive mirror technique as described by @Picdelamirand-oil do exist than sky is the limit. there is basically know need to analyze anything in real time. I hope what he say is true....than even the most modern AESA, multiple AESA can be tackled simultaneously.

I would like to know more about this adaptive mrrior tech. Tilldate I have not come across anystuff which has it as it needs extremely high processing power which we do not have today. But even if it is true, how many radars can be tackled at the same time remains the question.

The difference, I think with a very very rudimentary understanding is as follows. You and vstol are talking about jamming. Piced is not. He is talking about another approach.

We both know what we are talking about and also what @Picdelamirand-oil is talking. Our question is not about tech but about the number of reflections this so called mirror tech can handle when each frequency is being changed. What is the limit of this mirrior tech?

 

[JustCurious]

In all-out war, it will take 2-3 days for IAF to take over their skies. It's pretty standard for a superior air force.

Whether they can manage it, only a war will tell.

Superior being the keyword - IAF is yet to demonstrate any superiority.
It's track record during last 2 decades hasn't been much to speak of.

If you are referring to numbers, yes we do have some 1:1.5 kind of numerical superiority.
But, we have PLAAF to handle as well, while PAF can bear their entire force upon us.
So, we are clearly numerically crippled as well - until Rafale is inducted in meaningful numbers beyond 36 or MKI's get upgraded.

MWF is way too distant in future.
AMCA - well
Let's just hope PAKFA works someday, as it is expected to be.

 

[suryakiran]

I would like to know more about this adaptive mrrior tech. Tilldate I have not come across anystuff which has it as it needs extremely high processing power which we do not have today. But even if it is true, how many radars can be tackled at the same time remains the question.


We both know what we are talking about and also what @Picdelamirand-oil is talking. Our question is not about tech but about the number of reflections this so called mirror tech can handle when each frequency is being changed. What is the limit of this mirrior tech?

Aah ok. My logical (and very rudimentary) understanding seemed to be that, picdel seems to be suggesting a mechanism where the effort is on not spoofing the return, but rather on ensuring the return is not Rafale. So no matter what the frequency, it will be sent somewhere else.

But, will now keep quiet and read more about the discussion you are having. Very interesting and enlightening.

 

[Picdelamirand-oil]

I would like to know more about this adaptive mrrior tech. Tilldate I have not come across anystuff which has it as it needs extremely high processing power which we do not have today. But even if it is true, how many radars can be tackled at the same time remains the question.


We both know what we are talking about and also what @Picdelamirand-oil is talking. Our question is not about tech but about the number of reflections this so called mirror tech can handle when each frequency is being changed. What is the limit of this mirrior tech?

There is no limit in principe but there is practical limit due to processing power for exemple. I don't know the limit but I think this was 1 radar before DEDIRA and about 20 radar after DEDIRA. But even if it is one radar, it could be usefull if it is the seeker of the missile coming to you!

After that the MDPU is to day equipped with an electronic board with one or more processors for processing. So far, it has been preferred to increase the processing power of this board rather than multiply their number. But there are 18 slots, and there is room to add an extension for 18 more slots. So if my evaluation is correct and if you want more you can multiply by 36 the number of processed radar, that's 720 maximum (today). In the future the power of each individual board may increase.

 

[Picdelamirand-oil]

If adaptive mirror technique as described by @Picdelamirand-oil do exist than sky is the limit. there is basically know need to analyze anything in real time. I hope what he say is true....than even the most modern AESA, multiple AESA can be tackled simultaneously.

You need one mirror for each Radar location, so you need processing power to upgrade in real time all your "adaptative Mirror"
what I called "adaptative mirror" is not the real processing description, it's an analogy for you to understand how we are able to manage such a fast reaction to the incoming signal. And we don't need to alter the first pulse to have a good efficiency we just need to alter the whole sequence for the ennemi radar to don't match its replica with the return of the Rafale.

 

[vstol Jockey]

You need one mirror for each Radar location, so you need processing power to upgrade in real time all your "adaptative Mirror"
what I called "adaptative mirror" is not the real processing description, it's an analogy for you to understand how we are able to manage such a fast reaction to the incoming signal. And we don't need to alter the first pulse to have a good efficiency we just need to alter the whole sequence for the ennemi radar to don't match its replica with the return of the Rafale.

Yes and how many radars can u do it with? The truth is that Spectra can be overwhelmed by multiple radars and missiles. It will always give max power and priority to the most dangerous one and will use its stuff to neutralise the most immidiate threat. So there is no stealth associated with so called active cancellation tech of Rafale. It is just a better evolved EW system and nothing more.

 

[Picdelamirand-oil]

Yes and how many radars can u do it with? The truth is that Spectra can be overwhelmed by multiple radars and missiles. It will always give max power and priority to the most dangerous one and will use its stuff to neutralise the most immidiate threat. So there is no stealth associated with so called active cancellation tech of Rafale. It is just a better evolved EW system and nothing more.

720 is not enough?

MMRCA 2.0 - Updates and Discussions

@vstol Jockey @Ashwin @Nikhil is it possible for spectra to acheive active cancellations against an aesa radar? There was discussion on this started by @BMD here's the link... Why active cancellation vs stealth is a myth • US approach is pure stealth...why? . US stealth technology is...

www.strategicfront.org

 

[randomradio]

Superior being the keyword - IAF is yet to demonstrate any superiority.
It's track record during last 2 decades hasn't been much to speak of.

If you are referring to numbers, yes we do have some 1:1.5 kind of numerical superiority.
But, we have PLAAF to handle as well, while PAF can bear their entire force upon us.
So, we are clearly numerically crippled as well - until Rafale is inducted in meaningful numbers beyond 36 or MKI's get upgraded.

MWF is way too distant in future.
AMCA - well
Let's just hope PAKFA works someday, as it is expected to be.

Do you know, after the Balakot strikes, we now have complete air superiority in Kashmir? That's the reason why we have been accurately pounding Pak Army positions beyond the LoC using UAVs.

After the strikes, the PAF completely retreated out of Kashmir and our UAVs have been flying inside their territory ever since.

Anyway, surge operations last 2-3 days, it's pretty standard, and that's when the OPFOR is erradicated as a threat.