Pakistan's Airborne Early Warning and Control Aircrafts

[blain2]

Yeah but isn't the standard fighter sized target 1metre sqaure? the su-30 is at the least 3m2 if not larger

I believe its 5m2 (Su-30) but the graphic just shows a supposed aircraft. I am sure when they tested out the Erieye's performance in Sweden against fighter sized aircraft, I would think they were probably using calculations for some platform in the Swedish inventory like Gripen/Viggen which are considerably smaller than the Flankers.

 

[HAIDER]

Some interesting comments about Saab and SU30..(mostly Indian comments)

AWACS carries lot of passive intelligence systems along with its active radar and these passive systems can detect at almost twice the range of radar. Saab 2000 Erieye AEW&C able to incorporate high-speed dash with low-speed loitering capability, with inherent fuel efficiency that meets demanding AEW&C requirements for performing a 180-degree turn in less than 30 seconds with an endurance of more than 9 hours. It carries self protection system not to forget the fighter escort. Pakistan's aircraft has five on-board operator stations, versus three on modified EMB-145s and Sweden's two upgraded Saab 340s, a service ceiling of over 30,000ft (9,150m) and a mission endurance of 9.5h. It carriesSaab HES-21 electronic warfare suite comprising laser, radar and missile approach warners and countermeasures dispensers.Erieye radar provides 150 Deg coverage to each side of its conformal array.Saab-2000 AEW&C uses new-generation radar transmit/receive modules with 60% higher output allowing Saab-2000 AEW&C to have increased the AEW range of over basic Erieye design.
And india don’t have R-37

Some additional information about the Saab 2000 AEW&C
Virtually all of the radar components have been replaced since the Erieye was first fielded in 1996, and all of the computer systems are COTS-based for cost-effective and rapid upgrade. Power output is around 20 percent greater than it was previously, although power requirements, and thus cooling, for the mission system have decreased by 30 percent. The effects of improvement can also be seen in a 53-percent reduction in system weight and 78-percent reduction in floor space. At the same time, computing power has increased a hundredfold.Backing up the radar is a sophisticated Saab Avitronics HES-21 ESM/protection suite that uses interferometer antennas and digital receivers for highly accurate tracking and ranging of emitters. HES-21 data is fused with that from the radar to provide detailed tracking, and it can generate its own tracks at ranges greater than that possible with the radar. The system also includes a comprehensive self-protection function, automatically controlling the launch of chaff and flares.Although the aircraft are pre-owned, structural life is not a factor. The airliner was designed with an initial structural life of 75,000 hours, and on average, the fleet has used less than 20 percent. Based on typical use rates, the remaining life of the AEW&C is more than 35 years, with options for further re-lifting. Another point to be noted is the fact that Saab 2000 AEW&C will be operating at higher altitude then the Saab 340 AEW&C allowing it to detect over the horizon targets at longer ranges.

My dear friend, N011M ables to engage only 4 missiles continuously, besides r-37's range is not 300 km., a sukhoi can be tracked by AWACS at a range 300 km. & the enemy will get enough time to counter(by SAM or fighters) sukhoi. In maximum times when AWACS gets threat signal it changes it's location
==============================================
su30 sees AWACS from 500km ,and yes r37 has range of 300km and how long it takes to fire 6 r37 ,and yes there will be more su30 to fight with fighters defending AWACS besides 10 su30
carrying r37

besides 6 r37 which weigh 4200kg su30 still has roome to carry upto 4 r77+2 r73
and if fighters defending AWACS come to counter those su30 which carry r37 then su30 still can engage them with r77 or r73

and if AWACS changes its location it can't out run r37 which is coming towards it at mach 6

su30 can engage 4 targets means it can 3 targets with two r37 per target

now if 20 missiles fired at each awacs and even 3-4 survive after heavy jamming and countermeasure it will make kill

for the same reason su30 carry more missiles with different types of seekers so that it can fire more missiles per threat to increase kill
kill probability


my main point is number matters because there are various counter countermeasures nowdays and to increase kill probablity against these EW systems one needs to fire more missiles per target

First of all let me say that currently uses NIIP N011M Bars passive electronically scanned array radar and it was speculated that SU-30MKI might start using the passive phased array Radar Irbis-E by 2010 for new build aircraft and later on current aircraft will be updated with IRBIS-E but now another option of AESA is explored for last batch of SU-30MKI
Maximally effective detection range for No-11M :
a. 245 km for RCS = 10 m2 target (F-15, Su-27)
b. 137 km for RCS = 1m2 target (F-16, MIG-29 SMT)
c. 78 km for RCS = 0.1m2 target (F/A-18 E/F, Rafale)
d. 45 km for RCS = 0.01 m2 target (NG stealthy cruise missies)
e. 25~30 km for RCS = 0.001~0.002 m2 target (F-35 A/B/C)
f. 14~21 km for RCS = 0.0001~0.0005 m2 target (F/A-22)
And these ranges will decrease in lookdown shoot down mode
In simple words, as Type99 have said that there is too many things going on and these can’t be handled by the just two man who have to control and navigate the aircraft and its weapons too. Phalcon Airborne Early Warning radar can stay in air for up to 10 hours without any need for air to air refueling due to improved engines and can hold radar that provides 360 deg coverage and lot of processing power and space for dozen or more operator with individual workstations. Beside radar Phalcon also have ECM and intelligence capabilities through passive means. It has rest area and basic facilities for the crew that can’t be matched by the Su-30MKI
So basically what su-30 offers is a very basic capability of forward controller incase a true AEW&C is not present and has no match for the capabilities of a AEW&C.

 

[blain2]

Blain2, I have to say he is right!
I tried to get more infos about the Phalcon and the Erieye system, to understand what the differences are and as Gucci Juice said it seems to be the intelligence gathering capability!

PAF will getting the 5 Saab 2000 AEW&C right? But Saab also offers the Saab 2000 Sigstar, which is an spy aircraft specially for signal-, comunications- and electronic signals- intelligence missions!

http://www.saabgroup.com/NR/rdonlyr...ECA8/7511/Saab_2000_ERIEYE_AEWC_Datasheet.pdf

http://www.saabgroup.com/NR/rdonlyr...14DFECA8/7512/Saab_2000_SIGSTAR_Datasheet.pdf

Wiki definition: Signals intelligence - Wikipedia, the free encyclopedia

Brazilian Embraer which uses the same Erieye system on their aircrafts also have 2 versions:
EMB 145 AEW&C
Embraer Defense Systems

EMB 145 MULTI INTEL
Embraer Defense Systems

You said that the Phalcon has a bit more detection range, but what I also found out is that it offers full 360° detection. The Saab 2000 Erieye (and all other aircrafts with similar radar on top systems) offers the full detection range only to 300° as the following video and article shows:

Erieye AEW&C Airborne Early Warning & Control mission system radar (Sweden) - Jane's Avionics

MDv2ABV6KHg[/media] - Embraer EMB145 ERIEYE vs BOEING 737 AEW&C AWACs
Also in the same article it is mentioned that:


To make it clear, it's not my intention to blame the Erieye system!
But the Phalcon system seems to offer all important intelligence gathering features in a single aircraft and in combination with the better platforms (the rotodome and the aircraft) it gives some advantages to IAF.

More infos to the Phalcon system:

Phalcon airborne early warning system (Israel) - Jane's C4I Systems

Phalcon Airborne Early Warning and Control (AEW & C) radar (Israel) - Jane's Radar And Electronic Warfare Systems

Phalcon

Erieye provides 360 degree coverage and no less than SAAB brochure states that (as has Mean Bird pointed that out above).

See the following to get a better appreciation of what SAAB 2000 is capable of. It is the most capable system produced by SAAB as of yet. In the PAF service, one of its dedicated tasks is to supplant our DA-20 ELINT platforms. The SAAB 2000 is fully capable of SigInt and ELINT operations with DRFM etc.

The first Saab Erieye 2000 AEW aircraft is currently undergoing flight testing in Grenada, Spain and expected to continue throughout the fall of this year. This is the lead of five aircraft ordered by Pakistan. Two similar aircraft have also been offered to Thailand, the first has already been ordered together with the first six Gripens, while the second is included as an option with six additional fighters, replacing aging F-5s. Previously, similar configurations were used with the Saab 340 and Embraer 145. Saab is currently promoting the longer, more spacious Saab 2000 platform for a wide range of special missions, as an attractive, cost effective solution for airborne early warning (AEW) missions.
(more...)


Saab 340 carries an Erieye AEW radar, in service with the Swedish Air Force. Photo: Saab
According to Matthew Smith, Director of Marketing – Airborne Surveillance Arena at Saab, these special mission platforms are derivatives of the regional airliner, including the Saab 340 and the larger Saab 2000 platform, which provides more spacious cabins, long-range and persistence at an affordable cost. The company proposes the smaller Saab 340 as Maritime Patrol Aircraft (MPA) search missions, while the larger Saab 2000 is better positioned for longer range MPA, as an AEW, carrying the dorsal Erieye radar and ESM A close-up depicting the superstucture carrying the Erieye radar system installed on the Saab 2000 aircraft destined for teh Pakistani Air Force. Photo: Defense Updatesystem. The Saab 2000 is also positioned to carry signal Surveillance, Targeting, Acquisition and Reconnaissance (SIGSTAR) mission.

The Saab 2000 platform has a cruising speed of 370 knots, it can climb to an altitude of 20,000 ft in 10 minutes, reaching operating area 1,000 nautical miles afar within three hours. It can operate from high altitude airfields, taking off with maximum load and fuel even at hot temperature. Flight safety is maintained throughout all flight conditions, including single engine operations, where the aircraft can maintain altitude at 20,000 ft. To extend mission endurance, Saab packed an extra fuel tank at the rear section of the cabin. For example, in the MPA and SIGnal Surveillance, Targeting, Acquisition, Reconnaissance (SIGSTAR) missions, the Saab 2000 platform can operate at a maximum range exceeding 2000 nautical miles, on a mission endurance exceeding 9.5 hours. The MPA aircraft can carry out a mission covering a 200 nm Exclusive Economic Zone (EEZ) for 5.5 hours at an altitude of 2,000 ft. The Saab 340 MPA can operate on shorter missions lasting 3.5 hours. It's maximum range exceeds 1,300 nm and endurance is about 7 hours. In the SIGSTAR mission, the aircraft becomes operational immediately after takeoff, performing COMINT, ELINT, ESM missions supported by real-time analysis or offline analysis both onboard and on the ground.

An Erieye radar fitted onto the Embraer 145 is in service with the Brazilian and Hellenic air forces. Photo: EMbraer

The Erieye 2000 AEW aircraft is designed as a more capable aircraft, compared to past generation Erieye. The improved radar can detect smaller targets, including hovering helicopters. The system also uses Identification, Friend /Foe (IFF) system, Electronic Support Measures (ESM) and Automatic Identification System (AIS) which all integrate into a complete surveillance system. The defensive suite is also integrated with the sensors, and comprises of Self Protection System, Missile Approach Warning (MAW) and Laser Approach Warning (LAW) sensors controlling chaff and flare countermeasures.

The radar, mounted on the dorsal superstructure is the main sensor of the Erieye system. Operating in AEW missions from an altitude of about 8,000 meters, Erieye can detect targets at distances beyond to 400 km, including aircraft, surface vessels, and even cruise missiles and other low radar cross-section (RCS) targets flying at 200 km range. Surface naval targets can be detected at a range of 300 km.

The cabin accommodates five operator consoles, which can share the operational picture with ground-bound control system via communications and tactical datalink. The spacious cabin has accommodations for rest area and a galley. It also houses a large fuel tank which provides for the extended range and endurance performance of the aircraft. Mission training, planning and debriefing systems are also integrated into the system.

Saab expects to use commercial Saab 2000 aircraft to be converted to special missions, as some of the 58 platforms currently in service are scheduled for major overhaul or modification. Although the company claims the system can be accommodated in other platforms, and has installed the radar on Embraer's EMB-145, the recently announced alliance between the Brazilian company and India's Defense Research & Development Organization (DRDO) to develop AEW aircraft based on Embraer's special-mission aircraft platforms leaves little for future cooperation with Saab.

According to Smith, commercially operated Saab 2000 aircraft have flown about 25% of their life expectancy, leaving 30-35 years of remaining special-mission life span on average. Preparing a platform for the special mission role requires significant modification lasting 6-8 months, including engine refurbishment in cases new engines are introduced, structural strengthening as required, bonded and anodized corrosion protection at manufacture ensures continued corrosion protection in salty environments for maritime operations. Aircraft are also installed with self protection systems (chaff dispenser and ESM pod on each wingtip and chaff/flare dispensers at the belly. Auxiliary power unit and cooling systems are installed at the aft section. The main sensors are located at the belly (MPA) or dorsal superstructure (Erieye) which requires the most significant changes, such as the additional superstructure installation for the Erieye platforms, involving dorsal, tail and wing strengthening, wingtip pods installations, and installations of self protection systems in the wingtip, nose belly and on the engine cowling.

 

[mean_bird]

Yeah but isn't the standard fighter sized target 1metre sqaure? the su-30 is at the least 3m2 if not larger

I believe the Su-30 has an RCS of 10-15m². F-15 (older ones) have an RCS of 15m² while F-16 has an RCS of 1.2m²

I think standard fighter size is considered 3m² by most people.

 

[SQ8]

The RCS you refer to are fully loaded for the F-15 and flanker series and a clean (no stores) for the F-16. Add missiles, pods to the viper. and the return grows exponentially.

 

[sancho]

Erieye provides 360 degree coverage and no less than SAAB brochure states that (as has Mean Bird pointed that out above).

See the following to get a better appreciation of what SAAB 2000 is capable of. It is the most capable system produced by SAAB as of yet. In the PAF service, one of its dedicated tasks is to supplant our DA-20 ELINT platforms. The SAAB 2000 is fully capable of SigInt and ELINT operations with DRFM etc.

I know that site and it was the reason how I came to know about those Saab 2000 Sigstar aircrafts.

In the SIGSTAR mission, the aircraft becomes operational immediately after takeoff, performing COMINT, ELINT, ESM missions supported by real-time analysis or offline analysis both onboard and on the ground.

Please check the datasheets from the official saab site that I gave and you will see that there is an AEW&C version and an intelligence version. IFF, AIS and ESM are stated there too, but only the Sigstar version has SigInt and ELINT features!
About the degree of detection, as it is statet in Jane's the Erieye has some ability to detect in front and back directions, but not the same as it has to the sides and specially not to track.

 

[blain2]

I know that site and it was the reason how I came to know about those Saab 2000 Sigstar aircrafts.

Please check the datasheets from the official saab site that I gave and you will see that there is an AEW&C version and an intelligence version. IFF, AIS and ESM are stated there too, but only the Sigstar version has SigInt and ELINT features!
About the degree of detection, as it is statet in Jane's the Erieye has some ability to detect in front and back directions, but not the same as it has to the sides and specially not to track.

I am aware of the Sigstar variant and while I cannot prove it to you that what Pakistan is getting has considerable ELINT capabilities, but it is a big enough clue to realize that Erieyes will be undertaking a role that is currently the purview of dedicated ELINT platforms in the PAF. There is a difference between a platform not having any or some capabilities to conduct ELINT missions. Erieye can do quite a bit of the ELINT work.

Secondly JANES is wrong because their information is not always on the dot. They have folks who search around and write articles (I know first hand all the mistakes they make with regards to articles they write about Pakistan). I am showing you a data sheet released by SAAB - the manufacturer, which clearly states 360 degree azimuth coverage and you are still arguing about JANES. Not sure why its so hard for people to see things as the manufacturer describes them? Here is another link that confirms 360 degree coverage:EMB-145 Erieye Airborne Early Warning and Control Aircraft - Air Force Technology

The 150 degree detection that has been oft-repeated was the case with the older platforms delivered to Swedish AF. Pakistan's key requirement was for full 360 detection and on-board operators to eliminate the need to transmit to ground stations for relaying to other nodes. Both requirements have been met by SAAB.

Secondly, ComInt/SigInt can be looked at in many different ways. All AEW&C platforms have some SigInt and considerable ELINT capabilities. However there are always dedicated aircraft whose sole purpose is to perform Sigint roles. The US can afford to fly dedicated SigINT/ComINT platforms like RC-135 Rivet Joint which do nothing but perform these roles. This particular capability does not take anything away from the primary mission of the Early Warning platforms which is to give a proactive situational awareness to defence planners. On this count, Erieye does a job just as good as any other contemporary AEW systems available on the market.

 

[sancho]

Erieye can do quite a bit of the ELINT work.

You are right about that I found some more pages of that datasheet and it says that the ESM includes some basic ELINT capabilities.

Saab+2000+AEW+&+C-7.JPG (image)
But still to gather more or all intelligence infos you need Saab Sigstar, or Emb Multiintell, that's why I said the main advantage of IAF Phalcon is that it combine that all in a single aircraft.

Secondly JANES is wrong because their information is not always on the dot. They have folks who search around and write articles (I know first hand all the mistakes they make with regards to articles they write about Pakistan). I am showing you a data sheet released by SAAB - the manufacturer, which clearly states 360 degree azimuth coverage and you are still arguing about JANES. Not sure why its so hard for people to see things as the manufacturer describes them? Here is another link that confirms 360 degree

The 150 degree detection that has been oft-repeated was the case with the older platforms delivered to Swedish AF. Pakistan's key requirement was for full 360 detection and on-board operators to eliminate the need to transmit to ground stations for relaying to other nodes. Both requirements have been met by SAAB.

As I said before, Jane is not saying that the Erieye don't has 360° detection, but that the full detection rate (300 - 400 Km) might only be right for 150° to both sides.
Let's see it logically, the radar on top is clearly oriented to both sides. There are no extra radars to the front and the back, like you can see it on the Gulfstream AEW&Cs with Phalcon radar:

http://www.flightglobal.com/assets/getAsset.aspx?ItemID=25153

So logically if there is some detection in these aeras, they can't be as capable as to the sides!
That's why I tend to believe Jane's, also it is not the only source that claims that this.
(Btw this source also exlains that 150° is the improved version!)

Saab 2000 AEW&C prepares for duty: AINonline

The Saab 2000 AEW&C is the latest iteration of the Saab Microwave Systems Erieye concept. The five-operator system has increased command and control capabilities, including the Swedish Link-E system.

The radar itself, which consists of 192 transmit/receive modules, has been improved with an extended early warning mode and the ability to spot hovering helicopters. Coverage has been increased to two 150-degree sectors (from 120-degrees, still with a 1-degree beamwidth), with range out to the horizon (typically 199 to 217 miles).

This source makes a comparison of AWE&Cs systems, but even though they talk about the older Erieye system (120° instead of 150°) it says the same.

AEW&C - Phased Array Technology Parts 1 & 2

The limitation of the two sided array is that it can only cover two 120 degree sectors abeam of the aircraft, leaving 60 degree blind sectors over the nose and tail of the aircraft, and reduced antenna performance from 45 degrees off the beam aspect.

Saab scans AEW market for new Erieye buyers

The aircraft's fuselage has been strengthened to carry the Erieye radar, while its vertical tail has been extended to compensate for the payload, which provides 150e_SDgr coverage to each side of its conformal array.

So far Erieye looks to me like a good AEW&C system, even I am still not sure about the 150° detection point, but it offers not so much capabilities like the Phalcon systems.

 

[Arsalan]

well for me the bottom line is that PAF must have taken all thes points into accounts that even we people know about-- i mean they are surely more professional then we or atleast most of us are!
this hase been become an obvious game plane now, both the nations wait for the other to get something so that they can buy a new tech to counter it! the SAAB deal must have also been made keeping in mind the IAF Su30 and the Phalcons! same is rumored about the IAF MRCA that the delay may have somthing to do with the PAF procurment and PAF wait for the MRCA to be finalized to decide waht we should go for, it may be only a rumor but surely carry some sense!

regards!

 

[circuitbaba]

Location of AEW

As par my calculations via Maps and maximum coverage of Pakistani and Indian Air space they should be placed at Mianwali and Khuzdar

Since we r getting 5 each of both Eeriye and ZDK-03 with a range of 450km
The range is confirmed for eeriye while the range for ZDK-03 is assumed
If we get the Hawkeye 2000 AEW on the P-3C then they can be stationed at Ormara or Karachi....to get maximum sea coverage of instrumental 550km APS-145 radar for the Hawkeye.....
Plz note i am not taking abt E-2C ....as par the agreement the same radr will be mounted on P-3C for Pakistan navy..

 

[mughaljee]

sancho Jee,
Nice information

 

[Rank]

 

[MaXimMaRz]

Location of AEW

As par my calculations via Maps and maximum coverage of Pakistani and Indian Air space they should be placed at Mianwali and Khuzdar

Since we r getting 5 each of both Eeriye and ZDK-03 with a range of 450km
The range is confirmed for eeriye while the range for ZDK-03 is assumed
If we get the Hawkeye 2000 AEW on the P-3C then they can be stationed at Ormara or Karachi....to get maximum sea coverage of instrumental 550km APS-145 radar for the Hawkeye.....
Plz note i am not taking abt E-2C ....as par the agreement the same radr will be mounted on P-3C for Pakistan navy..

Hi, can you elaborate how you calculated mianwali and khuzdar? is khuzdar for the western front?

 

[gambit]

As I said before, Jane is not saying that the Erieye don't has 360° detection, but that the full detection rate (300 - 400 Km) might only be right for 150° to both sides.
Let's see it logically, the radar on top is clearly oriented to both sides. There are no extra radars to the front and the back, like you can see it on the Gulfstream AEW&Cs with Phalcon radar:

http://www.flightglobal.com/assets/getAsset.aspx?ItemID=25153

So logically if there is some detection in these aeras, they can't be as capable as to the sides!
That's why I tend to believe Jane's, also it is not the only source that claims that this.
(Btw this source also exlains that 150° is the improved version!)

Saab 2000 AEW&C prepares for duty: AINonline


This source makes a comparison of AWE&Cs systems, but even though they talk about the older Erieye system (120° instead of 150°) it says the same.

AEW&C - Phased Array Technology Parts 1 & 2


Saab scans AEW market for new Erieye buyers


So far Erieye looks to me like a good AEW&C system, even I am still not sure about the 150° detection point, but it offers not so much capabilities like the Phalcon systems.

In order to have a better understanding of why there is such a limitation on this system, there must be an understanding of basic phase array operation...

In a phase array antenna, each transmit-receive (TR) element is essentially a miniature radar antenna. The antenna computer then modulate individual TR power output and the entire system exploit the wave superposition principle to effect beamforming and to move or electronically 'sweep' the main beam.

Superposition of Waves

The above link illustrate basic wave superposition operations.

If a single element is out of phase, even for a microsecond, or its power output is not as responsive as its brethens for any reason, the mainbeam at the very least will contain noise, or possibly malformed at certain sweep angle, or not as narrow as needed, and many other types of beam forming and control errors. It is better that the degraded element be disabled than to allow operation hence continuously having a negative impact on overall radar operation. With the wave superposition principle in play, the more TR elements there are in an array, the narrower the main beam and greater precision, or finesse, in beam control. Array elements choreography -- softwares -- can make or break an entire design, regardless of how well the hardwares were manufactured.

For a phase array antenna, when the main beam (or lobe) is 'swept' near either extreme ends, its sidelobes, and sidelobes are inevitable, begins to be compressed against the main lobe, effectively 'contaminating' or 'jamming' the main lobe, making target acquistion, tracking and targeting difficult. There is a direct relationship between array element counts, antenna size and freq employed. Radar engineers, particularly phase array antenna engineers, prefers high ghz freqs as these bands offers tighter main beams but at the expense of detection range. Once basic array operations are understood, one can easily see why for a two-sided array system like the Ericsson Erieye there are two 60deg blind spots, front and rear of the aircraft and why it is difficult to ascertain the validity of any claim above the 120deg practical electronic scan limits, like the Saab 340 system so claimed. Such an increase is not impossible, but until the client performed full tests under 'real world' conditions and analyze the data for himself, the client should be wary of any claim above 120deg.

Mr. Kopp did not elaborate on the advantages of an active array over the passive one. Not his fault as the article was not about those differences...

AEW&C - Phased Array Technology Parts 1 & 2

Another powerful feature which may be exploited only in active arrays, is the ability to control the gain of the individual transmit/receive/shifter modules.

Control, not merely of gain, of individual elements is an active array's greatest asset. For a passive array antenna, the system can only produce ONE transmit beam.

Assuming a typical two-dimensional system like that of a passive array. However, for an active array system...

a - The entire array is used to produce a single beam that is narrow in azimuth and elevation. A PESA system can only do this.

Here comes the good parts...With a couple of techniques called 'subarray partitioning' and 'spatial interleaving'...

b - Two independent arrays, each with half power and narrow. The black dots are elements that are on a different freq than the crossed elements. One can be for azimuth search, the other for elevation search. More detailed target resolutions for multiple targets than (a). Combat is imminent.

c - There are nine beams created by this partitioning scheme. The black dots are two narrow elevation beams and one narrow azimuth beam and are for general and detailed multiple targets search, especially if any of those targets are low altitude and slow or not moving targets like helos. The other six beams can be used for communication, ECM, data relays between friendly forces, etc...This partitioning scheme is useful for ships like the AEGIS system. Combat is underway.

d - Six individual beams. Each sufficiently narrow in azimuth and elevation. Useful against several targets. Practically jam-proof as each beam can employ frequency agility, pulse repition freq/amplitude/phase jittering and mono-pulse targeting solution. Each beam can also act as communication, data relays or ECM, depending on situation. Combat is underway and this is where an F-22, or any US fighter equipped with an AESA system, will shoot down several opponents, probably of Russian and/or Chinese junks, without them knowing their death warrants have been signed.

With multiple beams, each can be swept in direction independent of its brethens. Subarray partitioning is not for the faint of programming skills and low manufacturing technology base, especially if the intent is to install such a system into a small vehicle like a fighter aircraft where power supply and cooling are critical. This is why the Russians and the Chinese are at least one generation behind the US, even if they managed to roll out an AESA system that can be fitted into a fighter. The US is already installing AESA systems into older fighters like the F-15 and F-18.

 

[hj786]

Subarray partitioning is not for the faint of programming skills

I talked to a guy who was on the team that developed the Blue Vixen radar. He told me that one of the programming geniuses wrote his own word processing program in 3 days.