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Thread: AESA Radar range calculator.

  1. #61
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    Which essentially bring us back to square one. No matter, i will push forward. see what i could dig up later.

    Perhaps approach using cost break down of typical AESA would yield better result. Then again price may differs. So the result would likely differs by some margin.

  2. #62
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    Performance also contributes since some radars require a lot of support equipment as part of them. The AMDR contracts would cover ancillary and cooling footprint while the TPS-80 is air-cooled but comes with a trailer and other recurring hardware essential to the warfighter but not linked directly to the radar side or its RF components. You would need detailed BOMs to get to the bottom of this. Things get even more complicated when the OEM is essentially an integrator such as a Lockheed or a SAAB that is sourcing equipment form multiple suppliers that have their individual component BOMs and profit margins. At least with the likes of AMDR and TPS-80, majority of the organic components (at least the most expensive RF ones) are produced by the Prime but in case of the Space Fence, the 50K+ T/R modules are coming form a different supplier (iirc Cree) while other components are being produced by Lockheed. Needless to say, this will be proprietary information EXTREMELY closely guarded for competitive reasons.

    When you get into GaN, TRL and MRL numbers matter despite marketing and PR claims of a number of suppliers that they can produce and have something on the test set up. When you require X,XXX to XX,XXX GaN RF components a year, your mastery of manufacturing and the technical capability absolutely matters as far as yields and ultimate production cost is concerned. Contrary to marketing spin, this is not a level playing field when you get down to individual foundries or integrator primes.
    Last edited by bring_it_on; 11th October 2017 at 13:54.
    Old radar types never die; they just phased array

  3. #63
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    I think this should suffice for now.

    Click image for larger version. 

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  4. #64
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    Good job, Man!!!

  5. #65
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    @swerve

    Erieye-ER (one customer so far) has S-band GaN modules. I think the Erieye antenna is 8 x 0.6 metres, so about the same as your 2x2 metres. Dunno how many modules, though, or what power.

    The GaN modules are said to give a massive increase in detection range of VLO objects. Maximum range against big, high RCS things such as ships is still the horizon.
    I still have doubts about the high performance calculated by stealthflankers spreadsheet but if there is no mistake, it now makes perfect sense why some countries like Sweden go for S-band. Its not only economical but would have a high capability against LO up to VLO assets.
    SiC, silicon and GaA are all able to provide a 50W peak power per element, no strict need for advanced and expensive GaN modules.

    If there is no tight space restriction, a 6000 element array with low cost 50W elements provides the same range performance as a 3000 element, state of the art GaN 400W array.
    Thanks to stealthflankers sheet, this now becomes visible. As well as the extreme performance even lower power 50W non-GaN S-band TRMs can develop, exceeding line of sight endo-atmospheric range against any conventional target and providing stand-off EW range counter-VLO capability or/and burn-trough capability in heavy jammed environment.

    It now also makes sense why Russians skipped the Gamma-D radar and went for the Gamma-S, as its high power is sufficient to compensate better counter-VLO performance of L-band. On the other hand, you can't achieve power levels of 50W without more expensive GaN modules in higher bands such a X-.

    But I still don't know if PW of 100µs and PRF of 2khz would be applicable for such early warning radars as those data are only derived from that TRM datasheet I posted. I still would like to know what PRF and PW levels are common for VHF- to X-band radars in search mode or illumination.

  6. #66
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    You can try Radar tutorial's database

    One example for your interest would be the Seek Iglo
    http://www.radartutorial.eu/19.karte...rte007.en.html

    Example of VHF band.
    http://www.radartutorial.eu/19.karte...rte049.en.html


    Selection of PRF for early warning radar band will usually be much lower compared to higher band radar (X etc) Mainly because tradeoff between doppler and range ambiguity.
    ----
    For X band and higher we may have several different PRF. a fighter radar may have like 10-11 PRF. Consist of 1 Low PRF mode for SAR or MTI, 8 for Medium PRF mode, 2 would be high PRF for Velocity search.

  7. #67
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    Quote Originally Posted by PeeD
    providing stand-off EW range counter-VLO capability or/and burn-trough capability in heavy jammed environment.
    The table is strictly in no jamming environment.

    Quote Originally Posted by PeeD
    I would expect half wavelength spacing, hence a 2x2m array @ 4000 elements,
    S band with 15 cm wavelength (2Ghz).
    4000 elements=> 64 vertical and 64 horizontal lines
    If the aperture is square then its length 64×15÷2 = 480 cm or 4.8×4.8 meters with half wavelength spacing.

    S band with 11.5 cm wavelength (3Ghz) need 3.6×3.6 meters array for 4000 elements.
    Last edited by mig-31bm; 12th October 2017 at 13:58.

  8. #68
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    @stealthflanker

    Thanks, yes I also found those data from radartutorial to model my VHF and S-band radars with you spreadsheet.
    For the PW of VHF-band radars it seems to have been greatly increased in state of the art radars. Phase shift keyed signals are claimed to be 42*6µs for this P-18 upgrade: http://www.litak-tak.eu/en/products/radars/p-18ml/

    If I have interpreted it right it would result into an effective 252µs pulsewidth. Hence the performance of an AESA solid state P-18 would be more than double for the same peak power (speaking of Nebo).

    Then also the huge possible pulsewidth of 800µs for the AN/FPS-117 creates some confusion. But for low PRF it should be possible at max. duty cycle.

    @mig-31bm

    Jamming is not included, but the very high performance of large S-band arrays would not only be effective against VLO targets, but also increase the burn trough performance when jammed. Hence the range performance is a direct indicator for counter-VLO and (non-ECCM) counter-jamming performance.

    You and stealthflanker are of course right about the array size. It is about 3,6m x 3,6m for 4000 TRMs and just 1600 for a 2m x 2m array.

    However even those "just" 1600 S-band low power 50W elements would have a ~230km detection range against a 0,001m˛ target. This could easily mean that a VLO asset with a X-band performance of 0,0001m˛ would be detected at 230km stand-off range by that 2m x 2m array, in case the RAM/RAS (or also shaping) performance is decreased by 10dbsm @ 3Ghz.

    I'm surprised by those performance levels. To some extend it changes the view that L-, UHF-, and VHF-band assets are the best approaches for counter-stealth. Use brute force of a cheaper TRM technology (non-GaN, 50W, possibly air cooled tile modules) and with a large enough array, you get the job done at a much higher position accuracy.

  9. #69
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    I think this should suffice for now.
    This is something more recent...
    Attached Images Attached Images  
    Old radar types never die; they just phased array

  10. #70
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    very Good Job @Stealthflanker

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