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  2. "Computers cannot create information that they weren't given in the first place. Computers aren't magical. They cannot improve the resolution of a grainy photo to show the face of the killer reflected in a raindrop." With this I must strongly disagree. Computer(so well mathematics) can create data from nothing. Simplest pseudo-random number generator is doing pretty much that. Or for example camera in You smartphone is doing just that. Create colorfull image from partial data. Consoles do that in form of upscaling for example. " They cannot improve the resolution of a grainy photo to show the face of the killer reflected in a raindrop." Such system(algorithms) like in this vid are used in all kinds of CCTV for example(it's cheaper to run program on some ARM than buy hi res CCTV camera with good lenses).
  3. Maximum angular resolution is a function of beam width. Beam width is a function of antenna size and operating wavelength. An AESA might be able to wring a slightly smaller beam width out of a given antenna size and a given wavelength, but it is still subject to these same limitations. It's fundamental physics; you see similar-looking equations if you look into the maximum focal range of laser weapons. L band is an order of magnitude longer wavelength than X band. Wing antennas are narrower than nose-mounted radars. This supposed "wing mounted L band AESA radar" is going to have less than a tenth the resolution of the nose radar. Computer signal processing do a much better job of finding useful signals. A more capable computer can find information that a weaker computer would have to throw away as noise. But there are information theoretic limits. Computers cannot create information that they weren't given in the first place. Computers aren't magical. They cannot improve the resolution of a grainy photo to show the face of the killer reflected in a raindrop. If a radar has a small antenna relative to its operating wavelength then its beam will be quite wide. If there are two targets within that beam width at the same distance moving at the same speed then there is no possible way that the computer will be able to tell whether it's one target or two. There simply is not enough information for the computer to dig through to find out what is going on. Likewise, if a radar has a wide beam and it's engaging a moving target, it is going to have a hard time figuring out where exactly in this wide beam the returns are coming from. It can move the beam around until it stops getting return signal, but the edge of a radar beam isn't a clean and abrupt end, and if the target is moving it won't be able to do this quickly enough to get a precise location anyway. These are fundamental problems with the amount of information that the antenna can provide the computer. The computer won't be able to fill in the blanks.
  4. But does size rly matter? It's not simple antenna. And generally the more complex system get the more it can "bend physics". I'm quite sure there are many ways to made antennae much much smaller while not loosing resolution or even gaining by design complexity. Also after getting data from antenna then come insane amount of mathematics(imagining theories, algorithms, AI, whatever) that probably can made from seemingly useless data, perfectly usable thing.
  5. It's an Actively Electronically Scanned Array (AESA), but that does not mean it is a radar. AESA is just a type of antenna, it doesn't necessarily mean it's a radar antenna. It could be a transmit-only antenna, or a receive-only antenna. It can't be a radar. Or if it were, it would be the world's most singularly useless radar. This isn't a matter of experience or design finesse, this is a matter of fundamental radar antenna physics. That is not a large enough antenna relative to the wavelength it's operating in. It is almost certainly an IFF system, but one that uses an AESA. The way IFF works is that the aircraft with the IFF system gets pinged by a radar, and the radar sends a coded interrogation signal. The aircraft that receives this signal sends back a coded response, which identifies it to friendly forces. The problem with this for a stealthy jet is that the IFF system is broadcasting radio waves, which is decidedly un-stealthy and could allow any radar with a passive seeker mode to get a bearing fix on the aircraft. The solution Sukhoi is using here is an AESA IFF system. Instead of a regular antenna, the response IFF signals are transmitted through the AESA, which allows it to confine the signal to a very narrow beam. AESA has extremely high gain and very small sidelobes, so it can make the IFF beam much narrower than a conventional antenna. That makes it much less likely that an enemy eavesdropper will detect these signals and use them to locate the PAK-FA.
  6. In some parts of the internet, enthusiastic, shall we say, commentators suggested that the wing antennae on the PAK-FA were some sort of super-duper stealth-busting L-band AESA system. This is a completely stupid idea. While it is true that L-band radars work better against stealth aircraft than X-band radars typically used in fighters, an L-band radar small enough to fit into the wings of the PAK-FA would have such poor resolution that it would be useless. Producer itself state it's L band AESA radar. Also apparently it's already implemented in other SU planes. And generally they(Russians) have experience in L band radars. http://www.niip.ru/eng/index.php?option=com_content&view=article&id=22:-l-&catid=30:esa-with-ebs&Itemid=42
  7. Figure from an experiment, showing how ERA is drastically less effective when it is not oblique relative to the threat:
  8. Top image is a flamethrower. It appears similar to the LPO-50/Type 74, but different enough. Not sure on any name.
  9. The automatic grenade launcher is a QLZ-04.
  10. Gogo gadget @Khand-e
  11. Upper photo what is this thing? Weird shotgun with bipod/small grande launcher/electronic warfare thing/flame thrower/training device? Bottom how is that granade launcher called?
  12. More people are lurking in Small arms thread, including several verry acknowledge members, you will get an answer much faster there.
  13. Logical step after 30 mm programmable HE-frag shells were tested on Pantsir. Posted video a while ago
  14. photos are from this thread that's why question here
  15. we have dedicated thread for small arms for this type of questions.
  16. Upper photo what is this thing? Weird shotgun with bipod/small grande launcher/electronic warfare thing/flame thrower/training device? Bottom how is that granade launcher called?
  17. Four wheels sounds stable enough to make it into a technical.
  18. That's nice of Hezbollah to show their take over of an outpost that was already abandoned as part of the disengagement. They're just shooting randomly in the air, and that RPG sure isn't going to do anything to the hundreds of tons of concrete walls and bunkers of that outpost. Especially after most of it was demolished already with mines.
  19. Youtube tank videos are almost always crap unless they are from The Chieftain Under the Hatch series or Bovington Museum "Tank Chats."
  20. http://www.janes.com/article/69809/russia-working-on-new-medium-calibre-ammo
  21. Iranians love to name weapons "Heidar". Heidar-5 is BTR-60-based minelayering vehicle, Heidar-6 is BTR-60 with BMP-1 turret and this is 12.7 Heidar anti-material rifle.
  22. That is Bulsae-3 ("Phoenix") ATGM. MANPADS are version of HT-16PGJ.
  23. German naval Battlegroup in the Mediterranean sea ca. 2004
  24. The left side of the turret AFAIK houses the ATGM while the right side of the Turret houses the MANPADS. What kind of ATGM is shown here however you have to ask someone more knowledgeable than me.
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