Pakistan's Airborne Early Warning and Control Aircrafts

[Arsalan]

the news was not published today rather it is quite old one. there may be some changes in time frame. i hope you understand the point,

regards!

 

[gambit]

well i have to agrr with this, we never find out that weather the 360 degree coverage is as effective as it is in rest of 300 degree or is it with or without ESM, and if with it how effective is it??
the effeiciency of such platform wont ever surface as they are classified info!

regards!

Saab 2000 Airborne Early Warning and Control Aircraft - Air Force Technology

The system is capable of tracking multiple air and sea target over the horizon and provides above 20km altitude coverage, 360° coverage and has sea surveillance capability.

There are alot of acronyms thrown willy-nilly about. I pointed out a while back on why the claim of 360deg coverage by Saab should be suspicious. In order to understand why it should be suspicious, one must understand basic ESA antenna operation.

An ESA antenna works by the wave superposition principle...

Superposition of Waves

An individual transmitter-receiver (TR) element will simply produce a wave front radially from the surface it is mounted. But in above image example with an eight elements array, the wave superposition principle will produce a main beam at the center of the array. There is a complex relationship between element count and their spacing but that is beside the point for now. Suffice to say that main beam width is directly affected by overall antenna physical dimensions: The more elements, the tighter the main beam, which is desirable, and therefore the larger the antenna.

Individual elements are manipulated via power inputs which produces different individual wave fronts, then the wave superposition principle takes over and the main beam is electronically swept. Currently, ESA antenna design is restricted to flat planar configuration. Shaped and conformal arrays are still in the experimental stages. On a planar array, the main beam, no matter how tight, inevitably will come into contact with antenna physical limitations and undesirable sidelobes, which for an ESA is about 45deg on either side of the mainlobe, or main beam as some prefer to call it.

It is then evident that the larger the overall antenna physical dimensions, the tighter the main beam will be. Tight beams like 'pencil beams' produces highly accurate target information like the usual altitude, speed and aspect angle with respect to the transmitter. So in order for the Saab system to increase from 120deg to 150deg would mean either an increase in antenna size or increased freq employed or a delicate combination and balancing of both factors. But because this is still a planar design, it is very difficult to see how the main beam, or lobe, can approach literally 180deg coverage. I am willing to bet that the 360deg coverage claim is more for puclic dissemination than true technical capabilities.

There is also the issue called 'target resolution cell' when it comes to benefits of as tight a main beam as possible...

Definition: radar resolution cell

radar resolution cell: The volume of space that is occupied by a radar pulse and that is determined by the pulse duration and the horizontal and vertical beamwidths of the transmitting radar. Note: The radar cannot distinguish between two separate objects that lie within the same resolution cell.

Main beam dimensions affect cell dimensions. The appropriate analogy is dividing a fixed volume into individual cubes. The goal is to have as small a resolution cell (or cube) as possible in order to distinguish multiple targets. A B-52 will occupy multiple cells, say 100 for example, whereas two small birds inside one of those cells will be seen as one target. But then if a higher freq and/or a larger antenna are used or combination of both, then the two birds will be discriminated, and of course the number of cells that the B-52 occupy will increased, like 100,000 cells, for example.

But there is a downside to having a tight main beam and that is when volume search is involved. Obviously...Target information is available only when the main beam impact the target. In volume search another delicate balance must be achieved with main beam dimensions and sweep rate. The tighter the main beam the higher the sweep (or scan) rate must be. Going back to the individual cubes inside the larger cube. You want to produce those individual cubes as consistently as possible inside that fixed volume and the smaller those cubes the more time you have to use to create them. Simply put...The larger the volume the more time required to properly process the volume.

An ESA system will perform these tasks faster than the classic single transmitter mechanically motivated antenna system but is still constrained by these laws. Increased main beam dimensions equal to faster volume search but at the expense of target resolutions, and it is a dangerous situation if there are multiple targets like small fighters. See 'target resolution cell' explanation above. Greatest danger is with very low observables like the F-22 or F-35 where multiple aircrafts inside a cell are seen as one target and its perceived (or interpreted) single RCS could be dismissed outright as 'clutter'.

 

[sancho]

i never meant to offened you, sorry if you take it like that,
however it was rather strange that you again claimed that the Erieye will have a 150 degree coverage on both sides, makeing it 300 degree in total and rest of the areas will relay on other sources while the post was clearly claiming that changes have been made to original design to give it 360 degree coverage,,,
however, i agree that it do not have much to do with ones flag but the about the fact that how reliable the soource claiming a point is. in this regard i guess you will agree with the content brought up by various poster clearing the full 360 degree coverage!

regards!

I don't say 360° coverage is not possible, but all sources claims only a max of 300° radar coverage, as I said even the official Saab 2000 Erieye video shows detection only in this area and not in the 30° to front and back. Of course they don't mention it in detail, but there must be a reason don't yo think? The only thing I want to know is how else they achive the missing 60° of coverage (most likely through ESM) and with what performance.

I just read on some sites that he Saab 2000 is also positioned to carry signal Surveillance, Targeting, Acquisition and Reconnaissance (SIGSTAR) mission but would PAF version have this capability it is yet to know whereas any advanced AWACS will have it from beginning.

Now if that is true for PAF's version then your argument is pretty valid as it will add a "C" with AEW role of Erieye making it AEW&C. Otherwise this C only came with the help of Ground station which is a major difference between a classic AEW&C and AWACS.
Hope this will explain a little

The SIGSTAR is a special version of the Saab 2000 only for Siginit and Elinit gathering, not for AEW, both are 2 different aircrafts with differen arrays and antennas. Search in this thread, I posted some pics and infos about them before.

I am not talking about earlier versions i am talking about up to date data which states that Radar provide 360 degree coverage (with or without ESM system).

Me either, the earlier version was the Saab 340 which had also 2 radar arrays with a detection of 120° each, the actual Saab 200 was improved to 150° each.

 

[Arsalan]

I don't say 360° coverage is not possible, but all sources claims only a max of 300° radar coverage, as I said even the official Saab 2000 Erieye video shows detection only in this area and not in the 30° to front and back. Of course they don't mention it in detail, but there must be a reason don't yo think? The only thing I want to know is how else they achive the missing 60° of coverage (most likely through ESM) and with what performance.

no, not again,,
dear have you forgotten the post on last page, they explained the 360 degree coverage issue. how are you agian comming up with the same old idea of 300 degree. the Erieye PAF is going to get we modified according to PAF wish and now give 360 degree coverage...
now i gusss it is the same thing posted in last 20 or so posts, references provided, explanation give..
still if you think it is 300 degree, you are the einner dude,,, !

regards!

 

[sancho]

So in order for the Saab system to increase from 120deg to 150deg would mean either an increase in antenna size or increased freq employed or a delicate combination and balancing of both factors. But because this is still a planar design, it is very difficult to see how the main beam, or lobe, can approach literally 180deg coverage. I am willing to bet that the 360deg coverage claim is more for puclic dissemination than true technical capabilities.

Thank you for the explaination Gambit! What about ESM and detecting, or tracking aircrafts? Is that possible and in what distance could an aircraft be detected?
I am also interested in the Boeing 737 Wedgetail, can you say somthing about the radar performance of it, especially of the top array?
Could this plattform also be used with the Israeli Phalcon system?

 

[sancho]

the Erieye PAF is going to get we modified according to PAF wish and now give 360 degree coverage...
now i gusss it is the same thing posted in last 20 or so posts, references provided, explanation give..
still if you think it is 300 degree, you are the einner dude,,, !

regards!

Ok then explain to me please, how will it be modified to achieve the 360° coverage? Will it get 1 top radar array like the Boeing Wegetail? Will it get 2 radar arrays, one on the nose, the other on the back like the Gulfstream Phalcon AWACS?
There is only this claim of 360° but no real explaination how. The systems I mentioned above shows different ways to achieve that, but as far as I understand it, the Erieye won't get new radar arrays right?
Btw, feel free to disagree! I don't want to convince you, or somebody else. I only want to have a discussion about it and get new, or better infos about the systems. But as far as I only hear it is possible, without saying how, I also feel free to have a different opinion.

 

[BoggedDown]

I would guess attaching T/R modules in double sided S-shape or I-shape array (instead of straight l-shape array) would achieve 360 degrees.

 

[Arsalan]

Ok then explain to me please, how will it be modified to achieve the 360° coverage? Will it get 1 top radar array like the Boeing Wegetail? Will it get 2 radar arrays, one on the nose, the other on the back like the Gulfstream Phalcon AWACS?
There is only this claim of 360° but no real explaination how. The systems I mentioned above shows different ways to achieve that, but as far as I understand it, the Erieye won't get new radar arrays right?
Btw, feel free to disagree! I don't want to convince you, or somebody else. I only want to have a discussion about it and get new, or better infos about the systems. But as far as I only hear it is possible, without saying how, I also feel free to have a different opinion.

i am not objecting to difference in opinion. I am no one to object as this is a public forum and all of us have equal rights here,,,
the thing that i am concerned is that despite of being provided various articeles claiming 360 degree coverage you seem to stick to the idea. i am not an aeronauticle engineer who can explian how, all i can do is to provide you with articles my professionals that this is what it is , , , and i guess you have been through some good literature by now,
anyways dude it is your point of view and have every right to carry on with it, i cannot object. however i will always try to convince other members about my point with those articles as i take it as my right to avoid them to be misleaded!
discsussion with some costructive ambitions is always welcomed!


regards!

 

[paritosh]

I would guess attaching T/R modules in double sided S-shape or I-shape array (instead of straight l-shape array) would achieve 360 degrees.

in an electronically scanned array radar...t/r elements are best in perpendicular arrays('+' shaped..."-" for azimuth and "I" for elevation) to give an electronically steered 0-180 deg azimuth and 0-180 elevation...for a resultant 360 deg scan.

 

[PakShaheen79]

http://img386.imageshack.us/img386/7272/saab2000ig9.jpg

May this help. I see some thing like 360 in this poster but nothing like 270, 300 etc.

 

[pakarm]

AOA SIR WHAT IS AWACs/. WHAT I STANDS FOR

 

[Arsalan]

airborne warning and control system AWACS
however bro it will be better if you can search such small points by yourself. all you had to so was to type AWACS in google,,,,

Regards!

 

[PakShaheen79]

AOA SIR WHAT IS AWACs/. WHAT I STANDS FOR

AWACS ->Airborne Warning and Control System
AEW&C ->Airborne Early Warning and Control

AEW&C is newer and modern term. 95% of functions are same. With advent in technology now ops like C2,C3,C3I and C4I are also being associating with these kind of panes. purpose is pretty much same "looking deep into enemy air and ground space".

 

[sancho]

i am not objecting to difference in opinion. I am no one to object as this is a public forum and all of us have equal rights here,,,
the thing that i am concerned is that despite of being provided various articeles claiming 360 degree coverage you seem to stick to the idea. i am not an aeronauticle engineer who can explian how, all i can do is to provide you with articles my professionals that this is what it is , , , and i guess you have been through some good literature by now,
anyways dude it is your point of view and have every right to carry on with it, i cannot object. however i will always try to convince other members about my point with those articles as i take it as my right to avoid them to be misleaded!
discsussion with some costructive ambitions is always welcomed!


regards!

That's it mate, provide me an atricle that explains and not only claims how Erieye will achive that coverage and I'll follow your opinion.
I am mainly interested in this because IAF will have a similar system with the DRDO AWACS, but there is not much know about it so far. So understanding Erieye can help to understand, or compare DRDO AWACS later. For Pak members this could be interersting too I guess, because with KJ 200 PAF also gets another of this 2 array systems and there is also not much is known about it's capabilities. So if Erieye can achive 360° coverage with only 2 radar arrays it must be possible for KJ 200 too.

 

[Gin ka Pakistan]

So Pakistan will have two AWACS System in future
1. Swedish: 4 planes
2. Chinese: 2 planes

and both are not Compatible with each other so that means two system will have to be develop at the same time isn't that waste of money from PAF???