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Embraer Develops platform for DRDO AWACS ,20 more to be ordered

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well there seems to be 2 platforms of AEW&C in that pic. One is the EMB 145 and what is the one in the back ground?
 
We can create AESA radars on our own..but we cant make one for TEJAS...


probably the same reason regarding nuke-reactor..we could make a reactor decades ago,but we could not make one for ARIHANTH tiill few years back.
The reason is miniaturization..
Miniaturization was the problem with ARIHANTH and is the problem for TEJAS imo//

Apart from that one of the main reason was high g force on the fighter aircrafts. Thats why we could easily build a PD radar for ALH or transport radar it it wasn't working well when tested under high g. But think AESA will not be a problem for DRDO, they already mastered it in various fields.
 
so 3 are on order so 20 more to come totaling to 23 :chilli: .....great going IAF this aircraft will be capable of IN FLIGHT REFUELING ...which the pakistani counterpart lacks currently
:cheers:

We currently have 2 Phalcon radars mounted on the Il-76 platform


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1 more is going to delivered , soon

IAF is considering a purchase of another 6 Phalcons . It has been reported they have placed orders for more IL-76 but i cant verify that.

The 20 Brazilian platforms on order will be used by DRDO to make their own Indigenous AEW&CS

EMB1459Nov2008.jpg


http://*****************/wp-content/uploads/2008/07/cabs-aewnc-antenna.jpg
 
Thank God DRDO did not wanted to make also the aircraft by themselves. Somebody must have told the the top brass in DRDO "not to reinvent the wheel". We should follow the Israeli way of doing things. Take the good things from around the world and make it better.

Can any one pls tell me what is the difference b/n rotodrome and fixed antenna on an AWACS. What are the advantages and disadvantages?
 
Thank God DRDO did not wanted to make also the aircraft by themselves. Somebody must have told the the top brass in DRDO "not to reinvent the wheel". We should follow the Israeli way of doing things. Take the good things from around the world and make it better.

Can any one pls tell me what is the difference b/n rotodrome and fixed antenna on an AWACS. What are the advantages and disadvantages?

Basically a rotodome gives you continuous 360 degree coverage , with the fixed antenna (rectangular) there is possibility of blind spot at the front and back of the array.

But I think the Fixed antenna is cheaper ..And you can get around the blind spots by following a special flight path that involves taking turns at specific time intervals...
 
Basically a rotodome gives you continuous 360 degree coverage , with the fixed antenna (rectangular) there is possibility of blind spot at the front and back of the array.

But I think the Fixed antenna is cheaper ..And you can get around the blind spots by following a special flight path that involves taking turns at specific time intervals...


Yes you are correct.

Rotodome gives the 360 degrees azimuthal coverage, however, the mechanical spining of dome is not desirable. The vibrations of flight and mantinance requirements makes it pretty expensive.

The new technology of Smart antenna arrays does the electronic scanning instead of mechanical and thus much more robust and cost effective.

During my PhD here in UK, I had a chance to work with a professor of IIT Delhi for sometime. We worked on ASEA and SAR radar projects for DRDO. The requirements clearly states that they were looking for electronic beam scanning not mechanical one.

The trickiest part is to overcome the blocking of aeroplane structure itself to counter the blind spot . Fortunatley, DRDO have very bright minds working for them and I've seen some impressive methods to get the 360 degrees spherical scanning.

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Thanks to CABS and LRDE.... and Please can any one clarify this doubt for me, Iam not a technical person so forgive me.... When We can create an AESA radar for this, why not for LCA tejas???

Sir , I will try to explain in simple words . Most of members would be aware of this thing before hand bcoz its discussed many times before , but for others interested I am posting here.

When a AESA design is picked up there are three things that hinder a successful design

1)Heating issues + Duty cycle - major one
2)Design and placing of array/modules
3)Cost of developing TR module

If we closely look at the TR module developed by LRDE for AEW version - here it is
trmodules_big.jpg


And number of such modules for antennae as per DRDO brochure is 160modules in Active radar unit .
This 160 numbers of module is individually actually an 160 TRMM (Transmission Receive multi module ) where in each TRMM consists of -
-8 TR modules
-8 electronic power amplifiers
-Low noice receivers
If you look at the handout above each TR module has about 200W rating with 10% duty cycle .

If we calculate heat generated for total system its about 200w x 160 / 1000 = 32KW peak power , which amounts to 32 x 10 / 100 =3.2KW consistent Avg Power at 10% duty cycle .

Calculate same for individual module -
200W each or 2000Joules for a 10sec radar pulse transmission [ watt = joules / time ] at 10% duty cycle 20w or 200joules for 10sec pulse .
In other words 20joules of energy needs to be tackeled every second by each TRMM , 20joules for TRMM or 20/8 for each TR module .

Thats huge amount of heat required to be cooled off , in sense requiring wide surface area for effective controlling , and a better + Large cooling plate . What they did was scooped atm air to whole length of AAU to maintain uniform cooling of module and a Liq cooling pipe

In case of AEW radar bcoz its such large size and peculiar rctangular shape it can be managed but think about such ratings in Tejas where along with small size a circular section provides difficulty in maintaining uniform heat distribution, its practically impossible . Even if they miniaturize this , it will require considerable skill and time to arrive at a perfect design where cooling can be uniform . Not every design of AESA in this world has managed to put liq cooling pipes inside . For eg NIIR-Phaztron had done heat by employing conduction cooling to the airframe metal structure instead of plumbing cooling pipes . So it would practically require a new brick-design of Tr module diff from this AEW version
Just to give an idea TR module on F22 is size of finger nail , such is manufacturing capability /tolerance of Western countries . and even at that size we see TR module with 5-10 W consistent power . Infacr TAIWAN and JAPAN are so ahead - Hyundai managed to place a 50w rated TR module on GPS/Mobile sized device .

2) Second aspect - L band vs X band
TR module that we see here are L band/S band where as most modern AESA have and X band operating freq . This presents another challenge bcoz we cant directly use an L band array , X band has certain advantages
like Higher Freq
Shorter wavelength meaning that much smaller Antennae size for SAR resolution . While in case for L band as wavelength is larger you may miss certain smaller wavelength objects along with requirement of bigger sized antennae . L band is ideal for AEW not tejas.

Important thing to note further is placement of array units - The antenna array spacing should be precise to maximize power to the main beam; complex calibration is later required to achieve consistent performance with center beam sharpening and minimizing side lobe losses . All this in turn require time and funding + sophistication , that's why very few developed countries are going for AESA module manufacturing alone.

3) Cost
Dont know about other countries - But in USA manufacturing a F22 like TR module costs about 2000-3000$ consider a 2000TR module antennae and costs jumps to 4Mill of radar antennae + Software + Signal processors (COTS Processor etc ) and we have price of AESA radar = Mig21 .
Its a highly costly venture , whole Europe is busy catching up Americans who manufacture it in large scale for Military use/Commercial use . Russians till now imported from Taiwan .

Lets see and hope India does what it does best -Cost effective solutions

Resource for figures -
http://reflect08.drdo.in/CABS Dr. S...Intelligent Multi-Sensor System_LEAD TALK.pdf
 
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) Second aspect
TR module that we see here are L band/S band where as most modern AESA have and X band operating freq . This presents another challenge bcoz we cant directly use an L band array , X band has certain advantages
like Higher Freq
Shorter wavelength meaning that much smaller Antennae size for SAR resolution . While in case for L band as wavelength is larger you may miss certain smaller wavelength objects along with requirement of bigger sized antennae . L band is ideal for AEW not tejas.

The AESA radar for Tejas is indeed X-band. It will be fitted on the Tejas in 2014.

Yes, there are certain advantages of X-band as FC radar for fighter aircraft and L-band has its own advantages thats why most of the AWACS are L-band including our Phalcon and DRDO AWACS. While PAK FA has both X-band and L-band radars.
 
Thank God DRDO did not wanted to make also the aircraft by themselves. Somebody must have told the the top brass in DRDO "not to reinvent the wheel". We should follow the Israeli way of doing things. Take the good things from around the world and make it better.

Can any one pls tell me what is the difference b/n rotodrome and fixed antenna on an AWACS. What are the advantages and disadvantages?

DRDO does not design and manufacture aircrafts :taz: think before you type
:cheers:
 
Actual AWACS system don't use rotodomes anymore, because the AESA radar beam can be steered to up to 150°. Our A50 Phalcon uses 3 radar arrays placed in a triangle form, which means the beam moves around the aircraft, from one array to the other and not the whole dome.

E3 with rotodome and 2 radar arrays:

Usaf.e3sentry.750pix.jpg



A50 with 3 radar arrays in triangle form:

A-50Eview.jpg



Othe system that offer full 360° radar detection are the new Boeing 737 Wedgetail and the Israeli G550 Phalcon:

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The 737 MESA system has 2 radar arrays to the sides, just like Erieye, or our DRDO AWACs, but it also has an array on top that will provide some detection to the front and back parts.
The G550 Phalcon instead has no radar mounted on top at all, it uses 4 radar arrays around the airframe. 2 main arrays on each side, 1 in the nose and one in the back below the tail fin.
Although these 2 aircrafts can detect targets in front and back areas, the the detection range will not be equal to the side arrays, so not equal to the triangle, or rotodome system.

All systems with 2 radar arrays to the side only, will have blind spots to the front and back areas. The only difference will be how big those areas will be, because while the older Erieye system could only offer 2 x120° detection with the radar arrays, the improved one with PAF offers 2 x 150°. That means a gap of 30° to the front and 30° to the back, and not 60° like on the older system. It will be interesting to see how good and comparable the DRDO system will be!
 
Thank God DRDO did not wanted to make also the aircraft by themselves. Somebody must have told the the top brass in DRDO "not to reinvent the wheel". We should follow the Israeli way of doing things. Take the good things from around the world and make it better.

Can any one pls tell me what is the difference b/n rotodrome and fixed antenna on an AWACS. What are the advantages and disadvantages?

No We went for Embraer After The failure of Airavat, which was Mounted on top of HS-748

ASO_Airavat_in_1996_Test.jpg

BAeHawker%20Siddeley%20HS748%20AEW%20-%20India.jpg

Indian%20AEW1_small.jpg


Thats why we opted for different Platform, and More over DRDO does not manufacture aircrafts....
 

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