Sukhoi PAK FA

Steven Rogers

NaPakiRoaster
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No, that was not my point, it was just a real life example of corner reflectors being visible to radars. The whole thing started with EOTS being a astute corner reflector.

Please pay attention, you seem lost.
At that smal range the whole aircraft is a source of reflection....you're putting an object of 20mts size just 150-200mts away against a 10kWpower...the whole RCS thing is based on detection at beyond visual range,and not in front of eyes ....
 

panzerfeist1

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Did I denied the presence of hypersonic missile in the Russian programs..No...Russia is manufacturing GaAs based electronics since 80s,infact it was the first to use GaAs in the radars after introducing the PESA radar...all of its electronics even today use GaAs...their development in GaN is not well know but people busy on jumping on GaN being used by Russia in the defence....
GaAs from the 80s are different from the ones used in the late 2000s like size examples. Also numerous examples have been shown that KRET has made GaN EW systems for krasukha, khlibiny, tarantula and Himalayas, stating GaN was present in their EW systems in 2015, claiming they have switched to 20 watts in 2017 in their AESA arrays. But my main concern is the photonic integrated circuit production timeframe and that radars candidacy for the 2nd version of the Su-57. Because this news has been all over their articles and even straight from their companies.
 

StealthFlanker

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There are many types of corner reflectors such as dihedral and trihedral that have various intensity based on line of sight (LOS) and shape or degrees of corner reflector. @StealthFlanker as well as Steven Rogers, you both commented that the source/image I posted would have to have a bistatic radar to work. Okay I will post an obtuse corner reflector using monostatic radar measured by synthetic aperture radar (SAR).



View attachment 55861

Clearly a abuse angle is very visible to radar. The LOS is the most important factor as the illustration above shows the transmitter/receiver is sending out and receiving a signal. The ‘double bounce’ and various reflectors is for illustration only, they are real and there is more then just a ‘double bounce’ with certain corner reflectors but people overlook the obvious, the X Y axis of 0. Any corner reflector will be picked up on radar if the angles are right. While Intensity will vary on the types of corner reflectors.

Like this, which shows a 90 degree corner, which has the ‘double bounce, but also pay attention to the part in red:


View attachment 55862
It is very important to cite the full context of the photo rather than one image alone, and you are making the very same mistake that most people would make when they cite information, which is cherry picking what they looking for and completely ignore appearance contrary information
Let give the source you quoted a closer look:
Pay attention to the color scale on the right hand side, I have circled it so that it is easier for everyone to follow:

dihedral target.PNG

90 Degrees corner simulation:
90 degree angle.PNG


Obtuse corner simulation
obstute corner.PNG

If anyone still doesn't understand after looking at the parts inside red circle and bar, let me explain in simple words: in the right angle corner simulation, the RCS value of the corner hotspot reached 40 dB, whereas in the obtuse angle simulation the RCS value of the hotspot reached 0 dB. Before anyone say that only 40 dB different, what is the big deal?. I like to remind you that dB unit scale exponentially, 40dB different literally equal to 10,000 times different in magnitude. Why? because an obtuse angle doesn't cause the double bounce effect
canardvstailhc5.jpg





You obviously are blind, you think that the EOTS is “smaller” then the 101KS-V?
EOTS is generally considered better not because of the size, but because it is faceted, therefore the reflection lobe can be directed away from the source while a parabolic shape is more likely to have wide reflection lobe. Of course, that doesn't mean 101ksv make su-57 unstealthy or that Su-57 isn't a stealthy fighter.
Besides, if we talking about the size of the corner, there are many other bigger corner hot spots.
corner.jpg



The problem is that the Rafale tracked the F-22 for long periods of time in close dogfights. Part of it was corner reflectors, part of it was the top side of the F-22 presenting perfect 90 degree angles and part of it was Rafale pointing its radar into the F-22 engines
Rafale has an IRST with LRF so that all a moot point. Secondly, stealth aircraft are not invisible, even low RCS from close range can have the same effect as high RCS from long distance
1-5.png
 

StealthFlanker

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I posted scientific data. Stealthflanker started nitpicking my source by stating it was measured by biostatic radar and very unlikely to produce radar return at those angles, you started repeated and copyed his points so then I posted the same source using an obtuse corner reflector using monostatic method when at a different angle and now suddenly you are crying that the image was taken by SAR imaging to generate an image of RCS :lol:
I didn't say obtuse angle is invisible to radar, I say the double bounce effect that gives a right angle corner massive RCS doesn't happen for an obtuse angle. That why as you can see in the simulation, the RCS value for right-angle corner reflector is literally 10,000 times higher than the one for obtuse angle
 

panzerfeist1

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Since no one has access to anechoic chambers or if they did are not willing to disclose those features with estimate values to the public can we talk about precision of DIRCM systems next?

I do know that both 5th gen aircrafts will have them both on the top and bottom since 101ks-o was displayed that way from the beginning and thanks to garryas post here https://forums.eagle.ru/showthread.php?t=35070&page=348(i probably will be interested in creating an account there) we can conclude the F-35 will have that as well for the top and bottom meaning both aircrafts can engage air to air missiles. But the next question is the precision.

one aircraft covers 360 degrees of Mid-Wave IR, Short-Wave IR and Near IR, 360 degree passive detection and 120 degree radar coverage.

Other aircraft covers 360 degrees of UV detection, 360 degree radar coverage, some in different bands like L-band and option of 180 degree infrared coverage, 360 degree passive detection. The 2nd version will probably have higher and lower frequency radar tracking capabilities than the previous version like UHF, k-band 100ghz for 360 degree coverage making quite the use of the electromagnetic spectrum.

What offers the best precision in what ranges for each usage? for example K-band will be great at shorter distances but will suck compared to X-band at longer distanes. Near and midwave infrared coverage has to have its precision depending on its distances. Any added thoughts to this would be great.
 

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