F22 vs. IRST and radar jammers

Anything goes, as long as it is about the Lockheed Martin F-22 Raptor
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Scorpion1alpha

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Unread post30 May 2015, 09:23

eloise wrote:
Scorpion1alpha wrote:Let's get off the F-35 discussion here. This topic isn't about the F-35, isn't the F-35 forum nor do I care about the F-35 in this forum. Future F-35 stuff mention here will be deleted.

come on, why delete everything :( took me quite long to write that post :|

Apparently, you're not getting it. I'm also not going to repeat myself. If you do it again, it's going to happen again.
I'm watching...
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nicktheaircraftexpert

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Unread post14 Jul 2015, 18:59

hornetfinn wrote:For example OLS-35 in Su-35 is still nowhere as good as AN/AAS-42 produced for F-14D over 20 years ago.


You need to prove that
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Unread post14 Jul 2015, 19:07

nicktheaircraftexpert wrote:
hornetfinn wrote:For example OLS-35 in Su-35 is still nowhere as good as AN/AAS-42 produced for F-14D over 20 years ago.


You need to prove that

range
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nicktheaircraftexpert

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Unread post17 Jul 2015, 06:08

mrbsct wrote:The source wikipedia brought me to is the German Military website which said.

The range of the system is between 50 and 80 kilometers, but could be up to 150 kilometers. The target identification can be carried out more than 40 kilometers. However, the weather conditions

So can it find the F22 at 80 km? Maybye? However I am not sure if it can track it effectively or find good identification ,range, position and velocity for its Meteor Salvo to be effective. How effective is the rangefinding, tracking system on the Tyhpoon?

So the target identification is around 40-50 km depending on the wealthier conditions in my predictions. Picard said that the Typhoon can still find the range by using by " PIRATE can carry out kinematic ranging (either through a weaving maneuver by a single fighter or datalinking several fighters together)." How true is this? This seems rather tedious.

The Tyhpoon website says:
Once a target has been tracked and identified PIRATE can be used to cue an appropriately equipped short range missile, i.e. a missile with a high off-boresight tracking capability such as ASRAAM. Additionally the data can be used to augment that of CAPTOR or off-board sensor information via the AIS. This should enable the Typhoon to overcome severe ECM environments and still engage its targets.

So at 50 km it can still use heat seekers like the ASRAAM without knowing the range,direction and velocity? However I doubt it would be effective because ASRAAM only travels Mach 3.

A duel between the Tyhpoon and the F22 in my estimates, the Tyhpoon will be instantly tracked by the F22 radar instantly around 260 km-200 km due to the RCS of the Typhoon being around 1m2 when weapons are loaded. The F22 is stealth, LPI and can use ALR-94 to make radar even more LPI so there is no way PraetorianDAS can jam or track it. While the Eurofighter outdated doppler radar can be easily tracked and jammed.

The F22 plans the battle and gains a superior position such as above the Eurofighter out of the range of (PIRATE has only low azimuth when pointing up and F22 has higher flight ceiling)azimuth of the IRST. The Eurofighter has a superior missile the Meteor. No escape zones are around 25 km for the AIM-120B, and AIM-120C around 30 km(based on the report I found the that the improved AMRAAM in 2000 was supose to engage 9 g targets at 30 km, and Eurofighter pilots reporting they cannot escape 30 km F22 shots at Red Flag). AIM-120D is 50 percent increase range so around 45 km NEZ, 50 km if lucky and with the F22's superior kinetmatics to the F15's. The Meteor being three times the NEZ of AIM-120B is around 75 km NEZ.

So with the AIM-120D the F22 can beat the Eurofighter with superior positioning. But with the AIM-120C chances are lessened since IRST can find that range and its WVR. The F22 can fire at 50 km, to screw up the Typhoon's postioning to gain the upper hand at 30-40 km. In close range WVR, chances are lessened since Eurofighter has HMD and ASRAAM is better than AIM-9x.

If Eurofighter fought the F35, the F35's higher IR signature(lack of IR reducing nozzle and no supercruise)will put it at a disadvantage, plus it can carry only 4 AMRAAMs. Since its RCS is lower the CAPTOR can probably find it at 40-50 km unless the F35 decides to jam it. Also the F35 has bad kinematics so its NEZ is much lower than 45 km with the AIM-120D. If it came down to WVR, the Eurofighter has better manuerablity and the F35 can't carry the AIM-9x stealthily. The Eurofighter has a huge advantage over the F35 in WVR and BVR IMO.

Do you agree?



The PIRATE is a QWIP so it gets less affected by weather conditions
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eloise

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Unread post17 Jul 2015, 06:43

nicktheaircraftexpert wrote:
The PIRATE is a QWIP so it gets less affected by weather conditions

No
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disconnectedradical

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Unread post18 Jul 2015, 21:46

nicktheaircraftexpert wrote:The PIRATE is a QWIP so it gets less affected by weather conditions


What kind of weather? Fog? Haze? Smoke? The best frequency for penetrating haze is actually short wave IR, while mid wave IR is better for seeing through humidity. I believe PIRATE is dual band with both mid wave and long wave IR frequencies. QWIP does little in this regard other than potentially increasing the number of bands employed. With long wave the ambient emissions from ground objects becomes much more pronounced.

What is your source stating the PIRATE uses QWIP anyways?
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nicktheaircraftexpert

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Unread post19 Jul 2015, 03:12

disconnectedradical wrote:
nicktheaircraftexpert wrote:The PIRATE is a QWIP so it gets less affected by weather conditions


What kind of weather? Fog? Haze? Smoke? The best frequency for penetrating haze is actually short wave IR, while mid wave IR is better for seeing through humidity. I believe PIRATE is dual band with both mid wave and long wave IR frequencies. QWIP does little in this regard other than potentially increasing the number of bands employed. With long wave the ambient emissions from ground objects becomes much more pronounced.

What is your source stating the PIRATE uses QWIP anyways?


there are a bunch of sources if u want to you can look them up
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Unread post04 Dec 2015, 23:16

eloise wrote:Due to the principles that they work, deceptive jamming are quite useless against AESA radar

The deceptive jammer received enemy incoming RF signal , it analyse , and then re transmitted that signal with different characteristic , like different doppler , pulse width . In contrast to noise jamming, deception jammer tries to mimic the radar echo so that the radar will respond as if it is receiving an echo from another aircraft or ship.


So deceptive jamming have to receive and process signal before they can send out jamming signal
Here are some characteristics of AESA radar that make them very resistance to jamming : frequency agility , and random PFR , random scan pattern
Jamming is likewise much more difficult against an AESA. Traditionally, jammers have operated by determining the operating frequency of the radar and then broadcasting a signal on it to confuse the receiver as to which is the "real" pulse and which is the jammer's. This technique works as long as the radar system cannot easily change its operating frequency. When the transmitters were based on klystron tubes this was generally true, and radars, especially airborne ones, had only a few frequencies to choose among. A jammer could listen to those possible frequencies and select the one to be used to jam.
Most radars using modern electronics are capable of changing their operating frequency with every pulse. An AESA has the additional capability of spreading its frequencies across a wide band even in a single pulse, which equates to lowering the emission power, making jammers much less effective. Although it is possible to send out broadband white noise against all the possible frequencies, this means the amount of energy being sent at any one frequency is much lower, reducing its effectiveness

http://self.gutenberg.org/articles/aesa_radar


In general, high PRF radars are more resistant to ECM because their average power is greater. Changing the PRF in a random fashion is an effective counter to deception because deception ECM depends on predictability of the radar. However, because PRF is related to the basic timing of the radar, this technique results in additional complexity and expense. Random PRF has been employed as a very effective ECCM feature in some radars for many years and has the additional benefit of elimination of MTI radar blind speeds.

Scan pattern. The radar scan pattern can influence ECCM capability because it influences the amount of energy directed toward the radar target. An active tracking phased-array radar is quite ECM resistant because of its ability to rapidly scan its radar beam in a random fashion than in the regular circular or sector scan pattern of conventional radars. This irregular beam positioning would give the opposing ECM system little or no warning and make it impossible to predict where and when to transmit false signals. In systems where scanning is performed in the receiver rather than in the transmitted beam, such as those mentioned in the section on angle deception, ECM has no direct access to the radar scan pattern and thus has difficulty using that information to interfere with the radar system operation.

Frequency. Frequency agility is a significant ECCM design feature. Using components such as frequency synthesizers (something like those employed in radio scanners) instead of conventional crystal-controlled oscillators, some radars are able to change frequency within one pulse repetition time (PRT). This makes deception and jamming very difficult. The radar can be designed to change frequency automatically within a certain range, or this can be done manually.

http://fas.org/man/dod-101/navy/docs/fun/part11.htm

To effectively jam an AESA radar, you would need to use noise jamming. For a noise jammer to be effective , the signal to noise ratio that enemy received must be less than 1. To achieve that you either have to increase your jamming power or reduce your reflected signal , or both. F-35 use APG-81 to jam, AESA have very narrow beam, as a result jamming power are more focused at enemy's place. It's also have a tiny RCS, thus reducing the reflected signal significantly
Even if we assume both side use the same kind of jammer, it still much easier for a stealth fighter to jam a normal fighter's radar than the other way round. Here is why :

Image
not only that lower RCS reduce burn through distance , jamming power required will decrease in the same rate as RCS reduction ,50% reduction in RCS = 50% less power required to overwhelm real radar reflection with noise ( you can work it out for yourself , 99.9% reduction in RCS= 99.9% less power required to achieve same level of effectiveness , and so on )
now let take example of 4 aircraft :
1) B-52 : RCS = 100 m2
2) Mig-31 : RCS = 10 m2
3) Mig-35 : RCS = 1 m2
4) F-35 : RCS = 0.001 m2
now compared them :
from B-52 to F-35 then RCS is reduced by 99.999% =>99.999% less power require
from Mig-31 to F-35 then RCS is reduced by 99.99%=>99.99% less power require
from Mig-35 to F-35 then RCS is reduced by 99.9% =>99.9% less power require
( if you not good at math then use this http://www.percentagecalculator.net/ the lowest row )

so again a very powerful enemy radar : if F-35 need 5 kW jammer to shield it's radar reflection with noise signals then Mig-35 will need a 5 MW jammer , Mig-31 will need 50 MW jammer , B-52 will required 500 MW jammer , you can argue that bigger aircraft can carry more powerful jammer but remember even the SPY-1 only have power of 5 MW


What about rafale shooting passively a target at a distance far more than 10 nm at six o'clock as said by a test pilot?

What about using interferometry technique by RWR to allow precise ranging for firing solution?
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Unread post05 Dec 2015, 04:01

house_13 wrote:
What about rafale shooting passively a target at a distance far more than 10 nm at six o'clock as said by a test pilot?

there wasnt any actual shot , it was a simulated shot
and only at distance of 7.8nm ( not even 10 nm let alone further than that)
Image


if you look careful at my picture, they mentioned a method to estimate range again known emitter ( when you already know exactly the kind of radar that enemy have ) hence it will only work again stable emitter ( old mechanical radar ) whose frequency and pulse repetition interval (PRI) remain relatively constant from pulse to pulse. a
Image

house_13 wrote: What about using interferometry technique by RWR to allow precise ranging for firing solution?

you have some misunderstanding here
Interferometer are what used to determine the direction of the emitter , from that you can use the technique i listed to determine the distance to target . But interferometry is not something that determine range on it's own
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Last edited by eloise on 05 Dec 2015, 04:45, edited 1 time in total.
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Unread post05 Dec 2015, 04:11

One of the best ESM system today is the ALQ-218 on EA-18G
it use both long and short baseline interferometer, but still can only geolocate ground emitter
The AN/ALQ-218 utilizes a unique combination of short and long baseline interferometer techniques along with a patented passive ranging algorithmto provide precisionGeolocation of all ground-based emitters

http://www.northropgrumman.com/Capabili ... fault.aspx
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Unread post05 Dec 2015, 17:30

there wasnt any actual shot , it was a simulated shot
and only at distance of 7.8nm ( not even 10 nm let alone further than that)


But if you can do it at distance of 7.8 nm , you can do it further than that using the same method
the picture doesn't mean that this is its max range

if you look careful at my picture, they mentioned a method to estimate range again known emitter ( when you already know exactly the kind of radar that enemy have ) hence it will only work again stable emitter ( old mechanical radar ) whose frequency and pulse repetition interval (PRI) remain relatively constant from pulse to pulse.


Those methods are more effective against ground targets than fighters

Interferometer are what used to determine the direction of the emitter , from that you can use the technique i listed to determine the distance to target . But interferometry is not something that determine range on it's own


In THALES official site they say :
Using sophisticated techniques, such as interferometry for high precision DOA and passive ranging,

https://www.thalesgroup.com/en/worldwid ... ce/spectra

I can give you many links that say interferometry used for accurate measuring of distance , for example
A state-of-the-art interferometer can measure distances to within 1 nanometer

http://www.explainthatstuff.com/howinte ... swork.html
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Unread post05 Dec 2015, 18:21

house_13 wrote:But if you can do it at distance of 7.8 nm , you can do it further than that using the same method

Actually no , it much much easier to measure range at short distance because it easier for triangulation ( function of range and angle ) and also the rate of change are very high at short range allow easier measurement
house_13 wrote:the picture doesnt mean that this is its max range

No evidence that it possible at much longer distance like BVR

house_13 wrote:those methods are more effective against ground targets than fighters

actually estimate range by measure radiated power of a stable emitter is probably the only method that would be practical again moving air target

house_13 wrote:in THALES official site they say :
Using sophisticated techniques, such as interferometry for high precision DOA and passive ranging

https://www.thalesgroup.com/en/worldwid ... ce/spectra


:doh: come on ,pay attention to what you post
and passive ranging again ground emitter is much much easier than a moving air target ( i already explained the reason why )

house_13 wrote:I can give u many links that say interferometry used for accurate measuring of distance , for example
A state-of-the-art interferometer can measure distances to within 1 nanometer

http://www.explainthatstuff.com/howinte ... swork.html

it really doesn't matter how many links you give if you don't really understand what they talking about
have a look https://str.llnl.gov/str/Sommargren.html
there a certain reason why interferometer can measure distance very accurately in specific case
you need to understand the working principles first
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Unread post31 Jan 2016, 15:45

AN/ALQ-184 just power is 9.1 kVa = kW ? You can not know the power factor, how you can conclude ECM pod with 5 KW power can reduce RCS 50%?

http://home.tiscali.cz/falcon4/downloads/alq184.pdf

No ECM pod is yet strong enough to reduce 50% of RCS.

F-35 AESA radar jamming is just advertising, it has never been tested. You know the peak power of the APG-81 ? :bang:

Irbis-E has peak power rating of 20 kilowatts, even APG-77 can not jammer it, because APG-77 peak power is 12 Kw.
According to one of evaluation, the APG-81 has a capacity of only 2 KW

http://en.airforceworld.com/a/20150513/8_2.html

The radar just scan into the fuselage frame, it is detected by the RCS, RCS is what you do not understand, which is reflected signals of the fuselage to the radar detect-track

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Image

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Unread post31 Jan 2016, 20:13

indochina wrote: F-35 AESA radar jamming is just advertising, it has never been tested.

I'm not sure what you mean as the APG-81's EW capabilities have been demonstrated in flight tests and at Northern Edge for years.

2011 http://www.af.mil/News/ArticleDisplay/t ... -2011.aspx

2015 http://www..mil/news/docs/20150624_FighterTest.pdf

Irbis-E has peak power rating of 20 kilowatts, even APG-77 can not jammer it, because APG-77 peak power is 12 Kw.
According to one of evaluation, the APG-81 has a capacity of only 2 KW

http://en.airforceworld.com/a/20150513/8_2.html


An AESA jammer has several advantages, not the least of which is that it's signals only have to go half the distance of the radar's, so you cannot compare them 1:1.

Also, you read that link wrong. Here is the direct quote on the APG-81's "estimated" power.

Due to the small size of the nose of the craft, the APG-81 radar has less components than the APG-77, although there is currently no concrete figure, it is likely around 1,200, giving it peak power of 12 kW and average power of around 2 kW.


So, according to his estimation the APG-81 has a peak power rating of 12kW, not 2kW (that was the "average" power, not "peak"). I noticed that you did not quote his APG-77 peak power estimate that was 22kW.

He was wrong in one fact (not his fault as this was widely believed at the time), the APG-81 has over 1600 T&R modules, not ~1200. Using his power ratios that puts the APG-81 at 16kw peak power, not 12kw. Thanks to it being AESA based, it can also be focused into a tighter beam thereby increasing it's effectiveness-to-kW ratio.
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Unread post01 Feb 2016, 07:48

indochina wrote:AN/ALQ-184 just power is 9.1 kVa = kW ? You can not know the power factor, how you can conclude ECM pod with 5 KW power can reduce RCS 50%?

No ECM pod yet strong enough to reduce 50% of RCS.

No one say ECM reduce RCS , i said the lower the RCS is , the easier it wold be to jam adversary radar , and no it isn't speculation , it is basic physic , you cant even write simple English phrase so I don't expect you to understand it anyway

indochina wrote:F-35 AESA radar jamming is just advertising, it has never been tested. :

Yes it was tested

indochina wrote: Irbis-E has peak power rating of 20 kilowatts, even APG-77 can not jammer it, because APG-77 peak power is 12 Kw.
According to one of evaluation, the APG-81 has a capacity of only 2 KW

Whether it can jam or not depending on the reflection signal , peak power is irrelevance here
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