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    General Questions Thread:

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    medo

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    Re: General Questions Thread:

    Post  medo on Thu Jun 16, 2011 8:38 pm

    http://arms-tass.su/?page=article&aid=96098&cid=44

    Russian air force unit in Russian Far east receive two Su-30 planes and it they plan to receive at least one squadron of Su-30 planes. From photo it seems, that they receive Su-30MKI type of Su-30 with canards and trust vectoring system. I wonder which radar it have in nose, Bars-M or maybe Irbis?
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    GarryB

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    Re: General Questions Thread:

    Post  GarryB on Fri Jun 17, 2011 5:35 am

    The Su-30 in Russian air force service should not be confused with export Su-30s.

    Exported Su-30s are multirole aircraft used as interceptors, fighters, and medium strike aircraft.

    Domestic Su-30s were based on the two seat Su-27UB operational fighter trainer, but were intended for the role of mini AWACS type operations with other aircraft.

    The purpose of the Su-30 is to use its larger more expensive and more powerful radar (ie larger and more powerful than the standard radar fitted to Mig-29 and Su-27 base aircraft) and to direct other aircraft to intercept threats. The aircraft they control generally are smaller and operate closer to the enemy and do not turn on their radars though they will use passive sensors like IRST and helmet mounted sights.

    The purpose is to allow the aircraft to take full advantage of the powerful radars of the Su-30 while at the same time using the weapon capacity and small aircraft advantages of the smaller aircraft.
    For the enemy to find the smaller aircraft they will need to use their own radars which will give away their position and allow their engagement.

    In many ways it is a shift from using ground controllers looking at radar screens from ground based radars sitting in vans on the ground to sitting behind the pilot and moving with the air formation. It makes it much more mobile and flexible and of course makes low flying targets more visible too.

    The Russians didn't ignore the Su-30MKI technology and development... a lot of that stuff likely aided the development of the Su-35 and Su-34 as well as the Su-27SM and Su-27SM2 upgrades.
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    medo

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    Re: General Questions Thread:

    Post  medo on Fri Jun 17, 2011 8:59 pm

    The Su-30 in Russian air force service should not be confused with export Su-30s.

    You are correct, but this is the easiest way to explain differences between Su-30 which are now based in Kaukasus region and are without canards and trust vectoring system and Su-30, which are now in units in Rassian Far East and are equipped with canards and trust vectoring system.


    Domestic Su-30s were based on the two seat Su-27UB operational fighter trainer, but were intended for the role of mini AWACS type operations with other aircraft.

    As I know all Su-30 are based on Su-27UB. The rule, that you mention was dedicated for Su-30 in nineties era. The new Su-30 from this time is for sure multirole fighter the same as Su-27SM is. Maybe they will be used only as fighters and interceptors, but modern radars and electronics give them those capabilities. At least for SEAD missions with their new RWRs, which could work with anti-radar missiles.
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    GarryB

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    Re: General Questions Thread:

    Post  GarryB on Sat Jun 18, 2011 7:44 am

    Oops... I made the error I was trying to point out.... Embarassed

    These new Russian AF Su-30s will likely be Su-30MKK like aircraft.

    Very simply the Su-30MKK is a Su-30MKI but with all the foreign stuff replaced with Russian stuff and simplified a bit.

    There will be no Israeli or Thales stuff in these aircraft though they will likely have improved stuff over that which was sold to China in some areas the Su-30MKI will have superior components.

    A PVO, which is now air and space defence force Su-30 would be operated and fitted out for the Mini AWACs role. For the Russian AF I suspect this is a swing role fighter bomber to supplement the Mig-35s and increase the number of in service Russian aircraft able to carry new guided weapons against air and ground targets.
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    medo

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    Re: General Questions Thread:

    Post  medo on Sat Jun 18, 2011 9:29 pm

    A PVO, which is now air and space defence force Su-30 would be operated and fitted out for the Mini AWACs role. For the Russian AF I suspect this is a swing role fighter bomber to supplement the Mig-35s and increase the number of in service Russian aircraft able to carry new guided weapons against air and ground targets.
    [quote]

    I think Mig-31BM is also able to do the job of mini AWACS and operate a group of fighters and share radar picture with data link. Unfortunately there is nothing known about modernized Zaslon PESA radar in Mig-31BM, if it is on the level of Irbis or Bars-M radar. Sometimes I wonder if PAK-FA will be successor of Mig-31 or of Su-27. I think PAK-FA could replace Mig-31 and Su-35 could replace Su-27. Su-30 could be real multirole fighter with crew of two in VVS to fill gaps in all roles as air defense fighter, SEAD platform, fighter-bomber or as a platform for antiship missiles.
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    GarryB

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    Re: General Questions Thread:

    Post  GarryB on Mon Jun 20, 2011 10:31 am

    The Mig-31 had a digital datalink that enabled them to link up to 4 Migs flying 200km apart to create an enormous virtual antenna that could cover from ground level to high altitude with a length of over 1,200km of airspace to a depth of about 200km that could be covered.

    The new air and space defence will likely combine airborne, ground based and satellite based radar and optronics systems to achieve a complete air and space picture of "traffic" above Russia.

    I think the Su-30M would be a useful addition, but really don't think PAK FA would be best used as a Mig-31 replacement.

    Stealth is of little use for an interceptor, which has little to fear from enemy fighters and needs speed and a powerful radar to detect long range targets or small targets at medium ranges.

    A PAK FA will carry long range missiles for specific missions but it will more likely be taking down JSTARS aircraft and AWACS aircraft and also tanker aircraft and troop transports.

    It will not likely be operating in places where strategic bombers will be coming.

    The PAK FA and the Su-35 and Mig-35s will compliment each other... just like an AN-124, a Mi-26, and an Mi-17 compliment each other in that the An-124 can deliver large loads to medium sized airports and then the load it delivers can be broken down into smaller loads for the helos to deliver to smaller airfields in more remote locations where the material is actually needed.

    Regarding the new radar for the upgraded Mig-31BM I was under the impression that they are fitted with the ZASLON-M radar and the other electronics are upgraded too. Not AESA but a highly developed PESA with very good performance. The electronics behind the original ZASLON radar were very weak and just new electronics 15 years ago would greatly improve performance because it was a PESA radar design.

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    question plz

    Post  ASHRAF on Sun Oct 16, 2011 6:48 am

    dose anyone know the type of equipment in red box in su-30/27-mig-29 ??


    http://dl.dropbox.com/u/45388524/mig-29a.jpg


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    GarryB

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    Re: General Questions Thread:

    Post  GarryB on Mon Oct 17, 2011 5:25 am

    Would have to look up my LOMAC manual, but off the top of my head I think they are IR sensors that track the movement of the pilots head to determine where the pilot is looking.
    This is used to determine where the helmet mounted sight is being directed for the purposes of pointing the radar or seekers on armed missiles at targets.

    Austin

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    Re: General Questions Thread:

    Post  Austin on Sun Nov 06, 2011 8:43 am

    Mindstrom As we talk of RCS figures I wonder how Kh-101 with an RCS of 0.01 m2 and Kh-555 with RCS of 0.1-0.2 m2 will be effective in penetrating NATO/US layered air defence ?

    Here is what yefim gordon mentioned in his book Russian Strategic Aviation.

    The flight testing of the Kh-101 has already been completed. This missile weighs some 2,200 - 2,400 kg , the weight of warhead is 400 kg. According to press reports, the Kh-101 has a maximum range of 5,000-5,500 Km a variable flight profile at altitudes ranging from 30 - 70m to 6000m , a cruising speed of 190-200 m/s and a maximum speed of 250-270m/s. It can well be classed as a low-observable flying vehicle because the radar cross section of the Kh-101 is 0.01 m2. The missile is equipped with an electro-optical system for correcting the flight trajectory and with a TV guidance system for terminal guidance. This ensures the hitting precision with a deviation of some 12- 20m.

    The upgraded Tu-95MS can carry eight Kh-101 missiles on four wing pylons. The same missile will also equip the upgraded Tu-160 which will be able to carry six missiles in each of its two weapons bays total of 12 Kh-101 or 102 missile. The highly accurate guidance system of the Kh-101 and its combined HE/fragmentation/penetrating warhead will enable one modernised Tu-160 to fulfil tasks previously achievable with an entire regiment of bombers. The upgraded version of Tu-22M3 is capable of carrying four Kh-101 missiles or six to eight Kh-SD
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    Re: General Questions Thread:

    Post  GarryB on Sun Nov 06, 2011 11:40 am

    As we talk of RCS figures I wonder how Kh-101 with an RCS of 0.01 m2 and Kh-555 with RCS of 0.1-0.2 m2 will be effective in penetrating NATO/US layered air defence ?

    Surprise is the key... if they don't expect them they will be very effective. If the enemy are alert and ready then a few might get through but some wont.

    The upgraded Tu-95MS can carry eight Kh-101 missiles on four wing pylons. The same missile will also equip the upgraded Tu-160 which will be able to carry six missiles in each of its two weapons bays total of 12 Kh-101 or 102 missile. The highly accurate guidance system of the Kh-101 and its combined HE/fragmentation/penetrating warhead will enable one modernised Tu-160 to fulfil tasks previously achievable with an entire regiment of bombers. The upgraded version of Tu-22M3 is capable of carrying four Kh-101 missiles or six to eight Kh-SD

    Interesting figures.

    The Tu-95MS used to carry 16 Kh-55s, with 10 under the wings on 4 pylons (one triple and one twin under each wing) and 6 in an internal rotary launcher.
    The Kh-101 and Kh-102 are much larger and can only be carried externally... but the 8 it could carry could be in addition to 6 older Kh-55 or Kh-SD missiles internally.
    The huge weapon bays of the Tu-160 mean the Kh-101/2 can be carried internally so that is normal.
    The Backfires numbers are interesting... All these cruise missiles are too big for the Backfire as its internal weapon bay is designed for the Kh-15 (which can be carried in loads of 24 internally in the Tu-160 so it is half the size of the Kh-55), so the Kh-101 and Kh-SD would have to be external loads.

    The Backfire has four external hard points so one Kh-101 on each pylon makes sense. With the Kh-SD the 6-8 missile capacity suggests two missiles under each of the wing pylons and one or two under each of the engine positions where they often carry multiple ejector racks for large numbers of bombs.
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    Re: General Questions Thread:

    Post  GarryB on Sun Nov 06, 2011 12:08 pm

    Surprise is the key... if they don't expect them they will be very effective. If the enemy are alert and ready then a few might get through but some wont.

    Note I am referring to a conventional attack.

    In WWIII with Tu-160s launching missiles at the US by the time they fly to their launch positions and fire their missiles, and those subsonic missiles make it to the target areas both sides' ICBMs and SLBMs will have wiped out all the main air defences and population centres... no one will notice the cruise missiles till they go pop.

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    Re: General Questions Thread:

    Post  Mindstorm on Mon Nov 07, 2011 12:28 am

    Mindstrom As we talk of RCS figures I wonder how Kh-101 with an RCS of 0.01 m2 and Kh-555 with RCS of 0.1-0.2 m2 will be effective in penetrating NATO/US layered air defence ?

    Here is what yefim gordon mentioned in his book Russian Strategic Aviation.


    Finally you have reached the central point Austin !!

    As even only simple logic suggest (you don't need to read the whole Eugene F. Knott's Cap 14 of Radar handbook ,to realize that  Very Happy ) we can say that among all the reradiating surfaces present at world of any shape and with any degree of electromagnetic superficial conductivity, the most low observable ,or "stealth" if you prefere,one is obviously .......a not existent surface !!
    Just for this reason no stealth aircraft will ever be capable to reach ,even by far, the overall level of low X band radar visibility of later cruise missiles, constructed with stealth features;  for the simple reason that where in an aircraft are present :  aerodynamic surfaces,cockpit, wings, air ducts, landing gears etc..etc...in a "stealth" cruise missile is present.......nothing.
    ...Do you know nothing is very "stealth "  Razz  Razz

    Is just for this motivation that russians ,talking of the capabilities of the Irbis radar, define its capability to detect at 90 km of range targets with an effective area of diffraction of 0,01 square meters -equal to the most low observable cruise missiles now operative worldwide - as a capability to detect super-low-observable targets and not simply very-low-observable targets ; those missiles in fact show an average area of diffraction more than an order of magnitude lower than the most low observable fighter aircraft (average RCS of 0,01 Square meters against 0,3 - 0,4 square meters).

    Austin

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    Re: General Questions Thread:

    Post  Austin on Mon Nov 07, 2011 9:04 am

    Thanks Mindstorm for replying in great details and explaining , appreciate it.

    Couple of related questions and you views on this.

    1 ) So 0.1-0.2 m2 RCS of Kh-555 and 0.01 m2 for Kh-101 is the average RCS of these cruise missile ?

    Since Shape impacts the way RCS is affected by different band ( X,L,S etc ) , I see Kh-55 ,555 has more or less cylindrical ( Kh-555 has jetisable fuel extension ) and Kh-101 has some shaping , but it is fair to say RCS for cruise missile is only X band specific ?

    2 ) Is it true the Sheez Size and Shape of B-2 makes its very low RCS across All Bands including VHF and More or Less B-2 remains undetectable by all known radars ?
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    Re: General Questions Thread:

    Post  GarryB on Mon Nov 07, 2011 11:05 am

    2 ) Is it true the Sheez Size and Shape of B-2 makes its very low RCS across All Bands including VHF and More or Less B-2 remains undetectable by all known radars ?

    Nothing is undetectable.
    In visible wavelengths it is easily detectible, and in IR it is apparently quite detectable too.

    Very simply one of the problems of detecting a B-2 with the RCS of an insect disappears if it flys high and fast... flying low there would be many real insects so looking for insects amongst them would be hard... of course I doubt there would be many in the north pole there are plenty of sandflys and mosquitos in summer in Siberia.

    The point is that the B-2 will be flying at medium heights at high subsonic speeds that no insect could even come close to.

    This means if you spot an insect approaching Russian territory at 800km/h at 13,000m then it is probably a B-2.

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    Re: General Questions Thread:

    Post  Mindstorm on Mon Nov 07, 2011 5:58 pm

    1 ) So 0.1-0.2 m2 RCS of Kh-555 and 0.01 m2 for Kh-101 is the average RCS of these cruise missile ?


    Yes, average RCS ,in the X band, for airborne long range look down radars, naturally ; for a simple question of inception ,for a ground based optimized low altitude radar those missiles would show a significantly higher RCS , but is also true that the tracking range of those type of low altitude AD radars is generally limited to some dozen of Km.



    Since Shape impacts the way RCS is affected by different band ( X,L,S etc ) , I see Kh-55 ,555 has more or less cylindrical ( Kh-555 has jetisable fuel extension ) and Kh-101 has some shaping , but it is fair to say RCS for cruise missile is only X band specific ?

    Yes absolutely ,in other radar bands (even only L band) theirs effective RCS would be more than an order of magnitude greater.


    2 ) Is it true the Sheez Size and Shape of B-2 makes its very low RCS across All Bands including VHF and More or Less B-2 remains undetectable by all known radars ?

    Is true that size of B2 contribute to degrade, up to a point, the degradation of shaping/RAM stealth features experienced by smaller LO/VLO aircraft against VHF radars ,but its "low observability" would be still extremely compromised ,in particualr against the last generation of russian high end VHF AESA radars and even more against AESA integrated multispectral ones with enormous tracking range ,like the new, monstrous ,55Zh6ME radar .

    Russians believe to have "resolved" the problem of low observable intruders long time ago ; it is not a case that, talking of the strategical level of airspace defence problem , procurement plans foresee a very robiust mass production of S-400 and S-300V4 , while all the R&D efforts are already all concentrated and projected (with S-500 and the S-1000 project ...designation still uncertain) for assure to neutralization of the new generation of offensive menaces : platforms/weapons attacking from low level orbital pacts at high hypersonic speed.


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    Re: General Questions Thread:

    Post  Austin on Mon Nov 07, 2011 6:15 pm

    Mindstorm wrote:Yes, average RCS ,in the X band, for airborne long range look down radars, naturally ; for a simple question of inception ,for a ground based optimized low altitude radar those missiles would show a significantly higher RCS , but is also true that the tracking range of those type of low altitude AD radars is generally limited to some dozen of Km.

    When you say ground based low altitude radar you would mean the Ka band types ?

    So tell me one thing the F-22,PAK-FA 0.3-0.2 m2 RCS is band specific like X-band , or do they cover L , S ,C ,E/F and other bands as well ? Both Aircraft do have shape that effective against broad band.

    I am fairly certain the VHF band will have little to no effect with the stealth of F-22 or PAK-FA.

    My understanding is RAM contributes to significant reduction of RCS and the RAM used on current stealth and non-stealth aircraft reduces X band visibility.



    Yes absolutely ,in other radar bands (even only L band) theirs effective RCS would be more than an order of magnitude greater.

    Thats true , but if you see Kh-101 closely what every has been released you will notice they have some sharp shapes , probably this missile is effective beyond X band due to use of Shaping ?

    The Kh-555/55 dont seem to have any shaping , so it gets its low RCS by virtue of its small size and application of RAM.


    2particualr against the last generation of russian high end VHF AESA radars and even more against AESA integrated multispectral ones with enormous tracking range ,like the new, monstrous ,55Zh6ME radar .

    The Nebo-M AESA VHF radar seems to use AESA for only Height Finding.

    Multispectral Radar means exactly what can you please clarify any details on 55Zh6ME ?

    Russians believe to have "resolved" the problem of low observable intruders long time ago ; it is not a case that, talking of the strategical level of airspace defence problem , procurement plans foresee a very robiust mass production of S-400 and S-300V4 , while all the R&D efforts are already all concentrated and projected (with S-500 and the S-1000 project ...designation still uncertain) for assure to neutralization of the new generation of offensive menaces : platforms/weapons attacking from low level orbital pacts at high hypersonic speed.

    Never heard of S-1000 project what it is ? The S-300V4 specs still remains classified and they arnt telling yet ,my bet would be its similar to Anetey-2500.

    Thanks for all your reply its a learning experience Smile

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    Re: General Questions Thread:

    Post  Mindstorm on Mon Nov 07, 2011 11:37 pm



    My understanding is RAM contributes to significant reduction of RCS and the RAM used on current stealth and non-stealth aircraft reduces X band visibility.


    Sorry Austin but your understanding is not correct ,RAM in a low observable platform represent by far the less influencing factor .
    At example talking of very narrow frontal head-on angle ,we can say that with shaping you can achieve RCS reduction in X band almost equal to about three orders of magnitude instead with RAM at maximum a reduction of a bit more than one order of magnitude , clear the difference of which we talk here ?


    Exist a famous phrase of David Overholser which speak volumes about that :

    " To reduce radar crossing reduction of an aircrfat exist four main laws : the first is surely shaping, the second instead is.... shaping , the third one ,instead ,must be considered ...shaping ,and the fourth radar absorbing materials ."



    So tell me one thing the F-22,PAK-FA 0.3-0.2 m2 RCS is band specific like X-band , or do they cover L , S ,C ,E/F and other bands as well ? Both Aircraft do have shape that effective against broad band.

    I am fairly certain the VHF band will have little to no effect with the stealth of F-22 or PAK-FA.


    Those figures represent the effective AVERAGE tactically exploitable RCS figures for those aircrfat in X/S band (taking into account a "critical", very narrow, head-on angle irradiation also Alexander Davidenko could have declared dramatic (but naturally completely worthless...) figures in the -40 dBSM order ,but you know between the two is not Russia the nation of marketing, Hollywood and wrestling...

    Making assumptions on degree of radar band coverage of PAKFA's low observability at today is not serious , what we know is that the requirement is a level of "stealth" in the region of F-22 (or just slightly lower ) without compromise combat range, hypermanoeuvrability a low /transonic and supersonic speed ,capability to employ a much more powerful and variegated panoply of weapon systems ,and integration of a full spherical very advanced sensor suit and DAS (i image that you is aware that ,at example, the sphere already present behind the cockpit is an experimental DIRCM covering rear emisphere ).

    My idea is that ,except with the integration of some innovative feature the technology of which is still not sufficiently mastered ,the first PAKFA operationalized will shopw a "stealth" mostly optimized for X/S band ,with the usual gradual degradation of its capabilities at the increase of the radar beams wave's lenght.



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    Re: General Questions Thread:

    Post  Austin on Tue Nov 08, 2011 1:33 pm

    Mindstorm wrote:My idea is that ,except with the integration of some innovative feature the technology of which is still not sufficiently mastered ,the first PAKFA operationalized will shopw a "stealth" mostly optimized for X/S band ,with the usual gradual degradation of its capabilities at the increase of the radar beams wave's lenght.

    Yes I am aware of the DIRCM system on top , hopefull they make it to Su-35S.

    If what you say is true and F-22 and PAK-FA is optimised for X/S band stealth , then why is the case that USAF calls F-22 Stealth as All Aspect and F-35 does not seem to be reffered as All Aspect Stealth aircraft ?

    PAK-FA in its current form seem to have stealth on its Frontal and Side but not Rear or under Belly if you have read Carlo Kopp Article on PAK-FA.

    I bet the PAK-FA average stealth is at a lower level compared to F-22 and only when the 2nd Gen Engine Comes and when it gets Flat Nozzle will it come very close to F-22 stealth.

    Why to you refer to export model of RVV-SD and RVV-MD being different that Russian Airforce one , is there any evidence to suggest that Russian Airforce weapons are better or export model is downgraded any way ?

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    Re: General Questions Thread:

    Post  Austin on Sun Dec 25, 2011 1:29 pm

    Can some one tell me the first missile RVV-AE has seeker stating X/Ku band , what does it mean it has dual band radar ?

    http://missiles.ru/_foto/MAKS-2011_1_news/IMG_1420.JPG
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    Re: General Questions Thread:

    Post  GarryB on Sun Dec 25, 2011 11:35 pm

    Think of the frequency band as being like a radio... because that is exactly what it is.

    If you have an old combined TV/radio you get a dial that lets you manually scan different frequency ranges. AM and FM are both radio frequencies, while VHF and higher frequencies are used for TV signals.

    Very simply an AM/FM radio has a switch so you can scan AM and FM frequencies looking for a signal.

    A missile with an active radar seeker can detect waves in the X band and the Ku band. Now that doesn't mean that the seeker can operate in the entire X and Ku bands... Japanese radios in some Japanese cars only have a limited FM range from about 86 through to about 91 MHz, while western radios tend to go much higher... often to 108MHz.

    So what we can say is that the early RVV-AE seekers operated in at least part of the X band and at least part of the Ku band.

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    Re: General Questions Thread:

    Post  Austin on Mon Dec 26, 2011 6:31 am

    Garry I get the impression that the Ku and X band radar are possible reference to IEEE and NATO bands , its not a dual band radar , it would be very difficult to have a dual band radar in that small space and with limited capacity for electronics , power ,raw signal processing capability.
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    Re: General Questions Thread:

    Post  GarryB on Mon Dec 26, 2011 12:38 pm

    It is all about antenna design.

    Have a look here:

    http://en.wikipedia.org/wiki/Radar#Frequency_bands

    Scroll down to frequency bands and you will see that the X band is the range of 8 GHz to 10 GHz, and the Ku band is 12 GHz to 18 GHz.

    This means that if the radar antenna in the R-77 has a frequency range of 9GHz to 14GHz then it operates in the X and the Ku band.

    I have a TV tuner card in my computer... it is a WinFast TV2000XP and it has two antenna connections... one for radio and one for TV because of the very different frequencies they operate require very different antennas.


    There is a bit of hard ware on the card and with a bit of software for the computer and the antennas connected properly in the FM band I can detect signals from 76MHz to 108Mhz. It doesn't work in the AM band so I can't detect AM band signals.

    In TV mode however I can detect signals in the VHF and UHF frequency ranges.

    Do you get it?

    A band is a range of frequencies and an antenna design might be designed to operate in a range of different frequency bands.

    Most televisions operate in the VHF and UHF bands though often they need two different antennas to work properly... a large antenna for the longer wave and a smaller antenna for the shorter wave.

    It has nothing to do with power or signal processing power... an AM/FM radio receives signals in two different bands, and it is only because FM is a weak line of sight signal that an FM radio often needs an extended aerial to operate properly, while the longer wave AM signal can be picked up with the internal aerial and can be picked up a lot further from the station because it bounces off the atmosphere better so can be picked up from longer range.

    Of course being a higher frequency you can pack a lot more data in the FM signal so you can have stereo sound or even digital radio with FM, whereas you can't with AM.

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    Re: General Questions Thread:

    Post  Austin on Mon Dec 26, 2011 1:31 pm

    Garry , I understand what you are trying to say.

    I have rarely seen radar designed in more than one band and i am talking of more capable bigger radar , the missile has small radar with limited power and processing capability.

    Having a dual band X/Ku for that seeker is impossible , I suspect it rather a X band radar or Ku band one of both depending if its talking of IEEE or NATO frequency.
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    Re: General Questions Thread:

    Post  GarryB on Mon Dec 26, 2011 10:05 pm

    Garry , I understand what you are trying to say.

    With respect Austin... I don't think you do.

    Designers don't just choose a radar frequency for fun.
    Specific frequencies have different properties which leads to different advantages and disadvantages.

    If you want to spot objects on the ground then a very high frequency radar can give an almost photo like view of things like terrain... that is why we get such a detailed view of the world, but the cost is processing power. Flash still images in front of a human at the pathetically slow rate of 25 frames per second and we think we are seeing normal live moving action... when in fact we are seeing still images flashed before our eyes at a rate of 25 frames per second.

    If you just want to detect the presence of a target then a long wave radar will ignore clouds and shaping of the object.

    Different frequencies have different performances in different conditions, so looking down yo might find changing frequency gives you better performance, while looking up a different frequency again might be better.

    The point is that the missiles seeker in an Active Radar Homing missile is a transmitter and receiver so it can choose the frequency to transmit... the fact that it can transmit, means it can also receive it, so it sends a pulse and listens for the signals it gets in return... using doppler shift (which is a property of the returning wave) it can separate moving objects from those that are still in comparison with their background).

    I have rarely seen radar designed in more than one band and i am talking of more capable bigger radar , the missile has small radar with limited power and processing capability.

    Size of the radar, processing power, and level of power have nothing to do with it. A transistor radio can detect several bands at once, in fact I have a short wave radio that can detect AM frequency radio waves from 530KHz to 1600KHz, plus short wave 1 from 2.3 MHz to 7 MHz, and Short Wave 2 from 7 MHz to 22MHz.

    In the case of a radio it only receives and does not transmit... in the case of this ARH missile its antenna both transmits and receives.

    The radio and Radar bands are not based on antenna capabilities.

    The radio transmitter for the Shturm and ATAKA missile operates in the 35GHz range which is high K or Ka band... and a very similar frequency to speed camera radar... very hard to jam.

    What makes it so impossible?

    Having a single radar antenna that can transmit and receive HF (10-100m wavelength) and MMW radar (7.5mm to 0.1mm wavelength) would be near impossible.

    Having a single antenna that can transmit and receive X (25mm-37.5mm wavelength) and Ka (16.7mm-25mm wavelength) Band radar signals is not that big a deal!

    Processing and power and radar size doesn't come in to it.. basically a radar that can operate in frequency ranges of 20mm to 30mm... which is a pathetic 1cm range of bandwidth is technically an X/Ku band radar. In fact a radar antenna designed to operate in the 24-26mm range is technically an X/Ku band radar... how can a radar with a 2mm bandwidth be impossible to make?

    Austin

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    Re: General Questions Thread:

    Post  Austin on Tue Dec 27, 2011 6:58 am

    I was talking to a friend on this , he was saying this could be either Ku or X band seeker , which means option for both of those and not a dual band one.

    Its really not easy to get a dual band seeker design and fit in missile cone , its expensive and secondly the power requirement and hardware is different.

    Its easy to have multiband passive seeker or receiver , but a dual band active seeker is a very tough ask and almost impossible.

    Even the latest meteor seeker operates in single J band.

    Actually multiband seeker is quite common in ARH missile like latest KH-31P

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