Comparative analysis of radar tech of Pakistan and India

[Omega007]

PSG simply indulges in "cut-paste" journalism; except that being the ardent "pamphlet-hound" that he is; he has many pieces of paper that he can cull out of. While Shiv Aroor is simply an "overgrown schoolboy" masqueraing as a Defence Journo.

Prasun is not a journalist in a true sense and he doesn't claim to be one either.He's more like an enthusiast.And about Shiv,less said is better.

 

[he-man]

Prasun is not a journalist in a true sense and he doesn't claim to be one either.He's more like an enthusiast.And about Shiv,less said is better.

pks just pastes the drdo slides on his blog with a shitty analysis which is neither readable nor understandable.
His analysis on mki upgradation was simply bullshit and i stopped following him after that.

 

[Omega007]

pks just pastes the drdo slides on his blog with a shitty analysis which is neither readable nor understandable.
His analysis on mki upgradation was simply bullshit and i stopped following him after that.

The feeling is not much different here either.

 

[amardeep mishra]

Mr mishra i would like a few clarifications.

1)Are mmic's being produced in india itself or made outside based on our dsign?
2)Whats the average semiconductor fab process size involved in nm?
3)Why do we fail to produce even a simple slotted array radar for tejas??Is it related to cooling?
4)If indeed drdo is making progress in uttam aesa can u please specify the average power of the t/r module??Also will the cooling system be indigenous??

Hi ,
here are the answers-
1)For certain applications yes,they are made in india,but you must understand that radar processing is essentially done on FPGAs because of their inharent advantage over fixed microprocessors etc.For one,FPGA's offer higher dynamic range in operations.And higher dynamic range translates in dBs for instance 8-24bit range gives rise to 90-140dB margin. Prominent FPGA manufacturers for radar processing are XILINC and ALTERA
2)As far as i remember last time, 0.8micron was the least SCL could manufacture(thats a lab under ISRO)- and with two upcoming FABs,our capabilities in this sector would be pretty much top notch! But for now,india sadly lacks a large scale FAB on the lines of china and japan.
3)I actually happen to have a detail technical document from LRDE pertaining to cooling requirements of LCA's AESA radar
4)The peak power handling requirement envisaged by LRDE,in their cooling system was somewhere close to 3.6-4kW, hence i am guessing the peak radar power should be well withing 4kW range

 

[he-man]

2)As far as i remember last time, 0.8micron was the least SCL could manufacture(thats a lab under ISRO)- and with two upcoming FABs,our capabilities in this sector would be pretty much top notch
3)I actually happen to have a detail technical document from LRDE pertaining to cooling requirements of LCA's AESA radar
4)The peak power handling requirement envisaged by LRDE,in their cooling system was somewhere close to 3.6-4kW, hence i am guessing the peak radar power should be well withing 4kW range

I think u meant .08 micron translating to 80 nm which is rather poor.
And an aesa with 4 kw power is practically shit in 2014 as even a simple slotted array like zhuk me is more powerful.

Compared to this the pesa of su-35 has peak power of 20 kw(average of 5).
Considering uttam aesa being small and having 700 t/r elements(estimate),,the power per t/r module is just 5w which is again poor compared to >10 for competing western/russian designs.

Zhuk ae made in 2007 had 4 watts per t/r module and u canimagine where russians are now.As for americans and israelis they might have reached 15 watts already.

 

[amardeep mishra]

Compared to this the pesa of su-35 has peak power of 20 kw(average of 5)

You must understand the russian radar design philosophy that tends to focus on higher PAP figures(resulting from a higher Peak power and aperature) in order to offset their inability to design sophisticated AESA radars on the lines of northrub gurman or thales etc.
A higher PAP is perhaps only good if you are interested in "longer ranges" or sometimes even blinding a less sophisticated enemy (with that massive 20kW of raw power).But practically you want a radar to do a LOT of things apart from having a decent range- This is a very very elaborate topic my friend and would take a lot of time!
On a lighter note,if we assume nose diamter of LCA to be ~650mm then this LRDE's AESA offers a PAP of close to 1.2kWm^2

 

[he-man]

On a lighter note,if we assume nose diamter of LCA to be ~650mm then this LRDE's AESA offers a PAP of close to 1.2kWm^2

Thats why i calculated the power per t/r module which comes as rather bad at 5 watts.
Forget russian aesa/pesa,,,,even french rbe2 pesa(now rbe2 aa aesa is installed on rafale) had a peak power of >8 kw.

Even apg-77 is estimated above 15 kw,,so power does matter,,the better performing a t/r module,the better it is.

At this current rate of progress when we make a good/decent GaA module for x band fighter aesa,,the world would have already moved on to GaN aesas.

 

[amardeep mishra]

Thats why i calculated the power per t/r module which comes as rather bad at 5 watts

Tbh,if you go through the site of ASTRA microwave corp,the power specification quoted by them in the datasheet for their x-band amplifier is 10w/piece i.e a single amplifier being capable of dissipating out 10watts of power- but i am not sure if this is the same transistor amplifier they use in the T/R module

the world would have already moved on to GaN aesas.

JFYI, -
DRDO has already designed GaN based TRMMs that can dissipate power in the vicinity of 80w

 

[he-man]

Tbh,if you go through the site of ASTRA microwave corp,the power specification quoted by them in the datasheet for their x-band amplifier is 10w/piece i.e a single amplifier being capable of dissipating out 10watts of power- but i am not sure if this is the same transistor amplifier they use in the T/R module

Looks doubtful as it means uttam aesa has just 300-400 t/r modules??!!
Is that figure for x band t/r element??

DRDO has already designed GaN based TRMMs that can dissipate power in the vicinity of 80w

Any link/proof??

Tbh,if you go through the site of ASTRA microwave corp,the power specification quoted by them in the datasheet for their x-band amplifier is 10w/piece i.e a single amplifier being capable of dissipating out 10watts of power- but i am not sure if this is the same transistor amplifier they use in the T/R module

They mention just elements for telemetry application for missiles

Radar

• Transmit/receive (TR) modules in UHF, L, S, C, X and Ku band for active apertures
• Low power microwave sub-systems for central acquisition radar (CAR)
• Electronic beam former for 3-D radar
• Microwave receivers
• High power 4-port circulators for radar applications.
• High power limiters

Telemetry

• Data and video telemetry transmitter systems for LCA and IJT
• Video telemetry receivers
• Telemetry tracking systems
• 1 watt and 10 watt telemetry transmitters for missile applications

Ground-based and sureveillance

• 8-Ch and 16-Ch frequency synthesizer for army applications
• VHF/UHF and microwave range front-end LRUs for ground surveillance applications
• VHF/UHF and microwave range biconical, dual-polarised antennae for ground surveillance applications
• * Technology from DLRL Hyderabad

Astra Microwave Products Ltd - Defence

 

[amardeep mishra]

@he-man
I think they have chnaged the website,for i remember very very correctly that ,2-3 years back they used to provide datasheet for their products in their site,or there must be that datasheet somewhere.
And as for that GaN based TRMM,you need to look into tech focus,i will send you those once i am free- probably after feb

@he-man
Here it is- go through this
Welcome to Astra Microelectronic Technologies Limited - INDIA

 

[he-man]

@he-man
I think they have chnaged the website,for i remember very very correctly that ,2-3 years back they used to provide datasheet for their products in their site,or there must be that datasheet somewhere.
And as for that GaN based TRMM,you need to look into tech focus,i will send you those once i am free- probably after feb

@he-man
Here it is- go through this
Welcome to Astra Microelectronic Technologies Limited - INDIA

I can't find any x band module,,only amplifiers are there!!

 

[Dillinger]

Hi ,
here are the answers-
1)For certain applications yes,they are made in india,but you must understand that radar processing is essentially done on FPGAs because of their inharent advantage over fixed microprocessors etc.For one,FPGA's offer higher dynamic range in operations.And higher dynamic range translates in dBs for instance 8-24bit range gives rise to 90-140dB margin. Prominent FPGA manufacturers for radar processing are XILINC and ALTERA
2)As far as i remember last time, 0.8micron was the least SCL could manufacture(thats a lab under ISRO)- and with two upcoming FABs,our capabilities in this sector would be pretty much top notch! But for now,india sadly lacks a large scale FAB on the lines of china and japan.
3)I actually happen to have a detail technical document from LRDE pertaining to cooling requirements of LCA's AESA radar
4)The peak power handling requirement envisaged by LRDE,in their cooling system was somewhere close to 3.6-4kW, hence i am guessing the peak radar power should be well withing 4kW range

That detailed document was supposed to be classified, the document itself states as much.

Uttam's been given 459.65 crore so far in funding as per the MoD's submission in front of the Standing Committee on Defence.

 

[Jayanta]

pks just pastes the drdo slides on his blog with a shitty analysis which is neither readable nor understandable.
His analysis on mki upgradation was simply bullshit and i stopped following him after that.

Prasun over Shiv Aroor any day....

 

[amardeep mishra]

That detailed document was supposed to be classified, the document itself states as much.

HI
You are right,the front page of that document says "restricted access"(but amazingly i got it off the internet,meaning that the document was "once" classified and now it has been de-classified). But thats not the point,the point is,the peak power of the radar is <4kW .
Here i would like to point out that the PAP of a radar is also a function(power and aperture being constant) of weighing function(or weighing coefficients ,often expressed in the form of a complex one dimensional matrix W(nx1) where n denote the number of antennae elements) used in the antenna(for instance ,for a 1000 element linear array hanning coefficients are better than chebyscheff coefficients).
It is this weighing coefficients that are responsible for the beam steering in any phased array radar- you remove this from a PA and it'll be no different from an ordinary radar.
Apart from contributing to the PAP,these weighing functions can generate precise nulls(i.e the radar will block any signal coming from that direction) at angles that can be manipulated(this property comes in handy when you're facing a hostile electronic jamming coming from a particular direction)
As we can see,in the picture below that,this particular radar produces nulls at roughly 72, 94, 120, and 153 degrees

picture courtesy antenna theory.com

@he-man
The power of a t/r module is determines by the amplifier it has(transmission path)- hence i asked you to look into x-band PAs of astra microwave

@Dillinger

here is what i was saying earlier,PAP as a function of linear array elements(n) was plotted for various weighing functions,one can see,the hamming window,offers the highest for a 1000element array

Picture courtesy- Aris alexopoulos and andrew shaw(DSTO- australia)