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Research seminar on Indian AESA radars.

amardeep mishra

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Hi everyone! These are some of the developments and my own thoughts based on my interaction and experience with radars.

Some of the major modes realized so far in uttam AESA radars are-
1)Air-Air mode
(a) Target acquisition mode
(b) Countermeasure support mode
(c) Performance monitoring
(d) Multi target track
(e) Weapon systems support.
2)Air to sea mode
(a) Target detection and tracking-ISAR and RS.
3) Air to ground mode
(i) Imaging modes
(a) Real beam mapping.
(b) Strip map
(c) Spotlight mode
(d) Air to ground ranging and terrain avoidance.
(e) GMTI
(f) GMTT
4) Target search and track.

All these modes are interleaved that means they are performed one after the other sequentially however since the time scales are in micro seconds it appears near simultaneous to the pilot.
The main constraint to the AESA is the power and cooling requirements from the fighter platform.
The design of X-band T/R modules package also known as "planks" have been realized in the country for the first time and patented! Yes LRDE bangalore hold the patent. They have settled with vaccum barzing technology for manufacturing these planks in India.
They're 3 variants of this plank-4,6 and 8 T/R module.
These QTRM planks form the building blocks of not only fighter jet AESA radar but also a lot of other strategic AESA radars under design and development at DRDO.
This fighter borne AESA has a minimum range of 115kms against a 2m^2 target.
@Oscar
@Nilgiri
Capture.PNG




 
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Mishra sahab I am not able to watch the video but do you know at what development stage we are now in uttam's development ??
 
@amardeep mishra the radar is pretty basic. Only 18 T/R modules (correct me if I am wrong here) and based on older GaAs technology. In comparison, the AESA radar for Thunder is going to have 1000 T/R modules. We don't have the details yet, but that type of density would indicate a GaN process.
 
@amardeep mishra the radar is pretty basic. Only 18 T/R modules (correct me if I am wrong here) and based on older GaAs technology. In comparison, the AESA radar for Thunder is going to have 1000 T/R modules. We don't have the details yet, but that type of density would indicate a GaN process.


First of all Pakistan does not build AESA.

And Uttam is a GaAs AESA but we have many GaN based AESA too. Soon the T/R modules will be replaced. When you have something of your own , replacement is easy. Production one will have GaN.

Also we are developing AESA for last 10 years.

LSTAR is the first AESA in use. Many land based and air borne radars developed as well.

oW3Wx0M.jpg
 
@amardeep mishra the radar is pretty basic. Only 18 T/R modules (correct me if I am wrong here) and based on older GaAs technology. In comparison, the AESA radar for Thunder is going to have 1000 T/R modules. We don't have the details yet, but that type of density would indicate a GaN process.

The 18 TRM one isn't for fighter aircraft. Probably a missile seeker or something. Fighters usually have between 500-1000 modules.

Number of modules does not indicate architecture process. All the 1000+ TRM radars that are in use today (mostly on US jets like F-15C and F/A-18E/F) are all based on GaAs process. GaN is useful for increasing the throughput & power transmission capability of each module - doesn't have to do with the module's size/number. What judges the number of modules is the scale of the MESFET semiconductor production process (measured in nm or grams), and how big the nose cone of the plane it's supposed to be put on is.

GaN for AESA-FCR is a very new process and no Air Force in the world currently uses it, not even USAF.

Induction of GaN-based AESA-FCRs in an operational role will only begin in the next 5-10 years in the West (F-35 getting operational, Rafale RBE-2AA upgrade, Captor-E upgrade, possible F-22 upgrade). It's doubtful if the PAK-FA's N036 has GaN right off the bat or not, and China afaik still hasn't revealed any GaN-based AESA-FCR.

So if someone says JF-17 will have GaN radar, I find that extremely hard to believe.
 
Getting few prototypes is one thing and getting it mass produced for active deployment is other. DRDO simply don't have capacity to mass produce for active deployment.
 
@amardeep mishra the radar is pretty basic. Only 18 T/R modules (correct me if I am wrong here) and based on older GaAs technology. In comparison, the AESA radar for Thunder is going to have 1000 T/R modules. We don't have the details yet, but that type of density would indicate a GaN process.
Hi @CriticalThought
No I am afraid you got it wrong. The AESA radar under development at LRDE bangalore features 736 T/R modules--also note that this radar is highly scalable which means the size of aperature can be gracefuly increased. The average power of the radar is close to 3.6kW resulting in a minimum range of 115km against a 2m^2 RCS target. However as explained in the video above, range depends on a lot of factors. Now these are the information available in open source. Indian research is much more transparent vis-a-vis chinese research hence it is much easier to obtain such seminar lectures and papers on various indian projects,OTOH chinese research is difficult to get our hands on. Kindly note, my objective was not to prove one system to be superior to another--because we simply cant do that as we lack any credible proof for the chinese system. You can get the patent documents of LRDE's patented X-band plank that forms the building block of various AESA radars that India is currently working on. These "planks" come in 3 models-
1) with 4 T/R module
2) with 6 T/R module and
3) with 8 T/R module
Also just because chinese one has 1000T/R module- it doesnt necessitate GaN wafers as against GaAs. Also note India has manufactured various GaN wafers for application to next gen of AESA radars.

No one can patent AESA, its how you design and produce them can be patented.



DRDO started working on AESA 12 years back.. with GaAs technologies in place,

https://www.drdo.gov.in/drdo/pub/techfocus/2008/oct08.pdf

We had started production in GaN fab as well,

http://www.thehindu.com/news/cities/bangalore/a-gallium-nitride-fab-in-the-offing/article7362861.ece
@CriticalThought
Tbh,India started working on AESA radars sometimes in early-mid 2000s, GaAs has been mastered and in fact patent was also filed for the design of QTRM plank. India is now working on GaN. However more than the hardware, AESA is more algorithm intensive these days. Developing algorithms that fully utilizes the capabilities of AESA is increasingly become a challenge.
 
Getting few prototypes is one thing and getting it mass produced for active deployment is other. DRDO simply don't have capacity to mass produce for active deployment.
Note : DRDO or in this case , the main agency leading the AESA development is LDRE - IS and ALWAYS has been A Development and Research Never Production!!!.... Once the Tech is mature enough for production , will be given to some other Gov Agency such as BEL or any other Private Co. for Production

Case and Point : it is the ADA that has designed and develop the LCA and it is only HAL that is the production/integrator
 
The 18 TRM one isn't for fighter aircraft. Probably a missile seeker or something. Fighters usually have between 500-1000 modules.

Number of modules does not indicate architecture process. All the 1000+ TRM radars that are in use today (mostly on US jets like F-15C and F/A-18E/F) are all based on GaAs process. GaN is useful for increasing the throughput & power transmission capability of each module - doesn't have to do with the module's size/number. What judges the number of modules is the scale of the MESFET semiconductor production process (measured in nm or grams), and how big the nose cone of the plane it's supposed to be put on is.

GaN for AESA-FCR is a very new process and no Air Force in the world currently uses it, not even USAF.

Induction of GaN-based AESA-FCRs in an operational role will only begin in the next 5-10 years in the West (F-35 getting operational, Rafale RBE-2AA upgrade, Captor-E upgrade, possible F-22 upgrade). It's doubtful if the PAK-FA's N036 has GaN right off the bat or not, and China afaik still hasn't revealed any GaN-based AESA-FCR.

So if someone says JF-17 will have GaN radar, I find that extremely hard to believe.

News from 2015
http://aviationweek.com/defense/saab-says-it-ready-produce-gan-radar-sensor
Saab says it is ready for volume production of a fighter radar using gallium-nitride (GaN) technology in an active, electronically scanned array (AESA). The Swedish company appears to be far ahead of competitors, none of which is known to have brought a GaN fighter radar to the same level of maturity. Saab displayed a model of the X-band radar’s antenna at the Seoul ADEX aerospace and defense show in October, promoting the system for South Korea’s proposed KF-X fighter.

Then in 2017
https://www.compoundsemiconductor.n...based-sensor-for-indian-fighter-aircraft.html
SAAB offers GaN-based sensor for Indian fighter aircraft
16th February 2017
AESA fighter radar and electronic warfare suite uses latest GaN and SiC substrates
Defence and security company Saab has announced that it is offering a GaN-based fighter sensor package for the Indian Tejas LCA Mk1A fighter aircraft. The package consist of a state-of-the-art Saab Airborne Electronically Scanned Array AESA fighter radar closely integrated with a compact electronic warfare suite using GaN based AESA technology.

The AESA fighter radar is developed by Saab with antenna technology based on the latest technologies using GaN and SiC substrates in combination with the latest generation of exciter/receiver and processor technology, giving optimum installed performance in a dense signal environment.

The radar has a complete mode suite which includes air-to-air, air-to-ground and air-to-sea capabilities. A built-in memory provides a tool to record a large amount of data from performed flights.

https://en.wikipedia.org/wiki/Zhuk_(radar)#FGA-35.283D.29
FGA-35(3D)[edit]
The FGA-35(3D) was first shown at MAKS in 2013. It's a GaN-based AESA, scalable, meant for various platforms with the version shown at MAKS having a 688mm(?) antenna and 960 T/R's. In an interview the new radar was mentioned to be weighing about 130 kg(for fighter planes)[20] and having a 200 km range for a 5-ton UAV version.[21] FGA-35(3D) was relabeled as FGA-35 while the original FGA-35 was relabeled as FGA-29.

GaN will naturally enable more T/R modules because its power efficiency means more power can be output for the same amount of cooling.

Hi @CriticalThought
No I am afraid you got it wrong. The AESA radar under development at LRDE bangalore features 736 T/R modules--also note that this radar is highly scalable which means the size of aperature can be gracefuly increased. The average power of the radar is close to 3.6kW resulting in a minimum range of 115km against a 2m^2 RCS target. However as explained in the video above, range depends on a lot of factors. Now these are the information available in open source. Indian research is much more transparent vis-a-vis chinese research hence it is much easier to obtain such seminar lectures and papers on various indian projects,OTOH chinese research is difficult to get our hands on. Kindly note, my objective was not to prove one system to be superior to another--because we simply cant do that as we lack any credible proof for the chinese system. You can get the patent documents of LRDE's patented X-band plank that forms the building block of various AESA radars that India is currently working on. These "planks" come in 3 models-
1) with 4 T/R module
2) with 6 T/R module and
3) with 8 T/R module
Also just because chinese one has 1000T/R module- it doesnt necessitate GaN wafers as against GaAs. Also note India has manufactured various GaN wafers for application to next gen of AESA radars.


@CriticalThought
Tbh,India started working on AESA radars sometimes in early-mid 2000s, GaAs has been mastered and in fact patent was also filed for the design of QTRM plank. India is now working on GaN. However more than the hardware, AESA is more algorithm intensive these days. Developing algorithms that fully utilizes the capabilities of AESA is increasingly become a challenge.

In your first video, the guys says the planks will be arranged in a semi-circular 4+6+8 configuration. That's why I thought there will be 18 T/R modules. It didn't really make any sense TBH.

Can you give me a link to this patent? Thanks in advance.
 
we have many GaN based AESA too.
In your first video, the guys says the planks will be arranged in a semi-circular 4+6+8 configuration. That's why I thought there will be 18 T/R modules. It didn't really make any sense TBH.

Can you give me a link to this patent? Thanks in advance.
Yeah sure @CriticalThought , here are the links for the patent and research papers-
https://www.rroij.com/open-access/d...le-of-active-phasedarray-radars.php?aid=42971

Here is the link of LRDE's patent filed in european patent office
http://www.freepatentsonline.com/EP1279046.pdf

You can go through it as well
http://capsindia.org/files/documents/CAPS_Infocus_RS_7.pdf
 
Yeah sure @CriticalThought , here are the links for the patent and research papers-
https://www.rroij.com/open-access/d...le-of-active-phasedarray-radars.php?aid=42971

Here is the link of LRDE's patent filed in european patent office
http://www.freepatentsonline.com/EP1279046.pdf

You can go through it as well
http://capsindia.org/files/documents/CAPS_Infocus_RS_7.pdf

Just for the sake of scholarly discussion, the journal's impact factor is only 5.621. It is not listed amongst internationally renown journals in electrical/electronics engineering

http://www.scimagojr.com/journalrank.php?category=2208

Note that the SJR metric used in the above link is even more restrictive than journal impact factor.

Then, the paper itself fails to provide any comparisons with contemporary systems. How is it better in terms of power consumption, rate of operation etc. from other international systems? This paper merely advances upon the previous achievements of Indian engineers. I really like the overall approach how you guys are gradually increasing your learning and capabilities, and doing it very systematically as well. But this is certainly not cutting edge research.

The patent itself doesn't seem connected with the research paper. I don't know if any other system has utilized a hybrid solution MMIC and MIC, but then again why wouldn't someone just used MMIC throughout?

I wish you guys good luck in obtaining the patent, but it is said that a patent in only worth if it has been defended in court.
 

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