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Karthi

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uat.jpg
l2-uav-targets.jpg
L7T TActical UAV.jpg


L& T Tactical UAV

Max take-off weight - 700 kg
Wingspan - 15 m
Max. payload - 140 kg
Max. endurance - 11 hours
Maximum speed - 60 m/s (115 knots)
Service ceiling - 7.6 km (25,000 feet)

Second picture is from L&T brochure , if anybody has editing skills, please clean it up
 

Karthi

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LRDE developed X band AESA experimental 64 element Active Antenna Array probably for gaining experience for UTTAM( My Guess)

Antenna Elements arranged in (16 x4) array.jpg


Antenna Elements arranged in (16 x4) array. Look at the Vivaldi antenna (Tapered Slot antenna both are same) only advanced western countries have this tech even Russia don't have this ( i never seen any Russian antenna with Vivaldi array , may be i am wrong) , you can see similar tech in UTTAM AESA

antenna front view with antenna elements.jpg


antenna front view with antenna elements

arrangemnet of TRmodules in the plank.jpg


arrangement of TR Modules in the plank.

cooling arrangement .jpg


cooling arrangement
rear side of the array..jpg


rear side of the array.

Transmit Receive Module(exploded view)..jpg


Transmit Receive Module(exploded view).

Transmit Receive Module(top view).jpg


Transmit Receive Module(top view)
 

Swiftfarts

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LRDE developed X band AESA experimental 64 element Active Antenna Array probably for gaining experience for UTTAM( My Guess)

View attachment 64116

Antenna Elements arranged in (16 x4) array. Look at the Vivaldi antenna (Tapered Slot antenna both are same) only advanced western countries have this tech even Russia don't have this ( i never seen any Russian antenna with Vivaldi array , may be i am wrong) , you can see similar tech in UTTAM AESA

View attachment 64117

antenna front view with antenna elements

View attachment 64118

arrangement of TR Modules in the plank.

View attachment 64119

cooling arrangement
View attachment 64120

rear side of the array.

View attachment 64121

Transmit Receive Module(exploded view).

View attachment 64122

Transmit Receive Module(top view)
I am not sure they are tapperd slotted array. Those are notch radiators for sure which is a good thing. For example Uttam bandwidth is between 2-3 Ghz max. a TSA will allow wider bandwidth upward of 5 Ghz easily. They were testing TSA based KA Band AESA seeker so I think they probably are developing one X band radar for upcoming AMCA. as for russians , yes it does look like that they are behind.
 
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Karthi

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I am not sure they are tapperd slotted array. Those are notch radiators for sure which is a good thing. For example Uttam bandwidth is between 2-3 Ghz max. a TSA will allow wider bandwidth upward of 5 Ghz easily. They were testing TSA based KA Band AESA seeker so I think they probably are developing one X band radar for upcoming AMCA. as for russians , yes it does look like that they are behind.

images.jpg


Notch radiator

1280px-Vivaldi-Antenna-Testing-In-Chamber.jpg


Vivaldi Antenna .

You may be right , but we developed Vivaldi Antennas for sure.
 

Swiftfarts

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View attachment 64137

Notch radiator

View attachment 64138

Vivaldi comes in different types.

You may be right , but we developed Vivaldi Antennas for sure.
Taper types.

main-qimg-4871efdcc7e1e8f7ff7e61e31978eda8.png


AN/APG 81 AESA ( F 35 radar ) look like use a version of stepped constant taper type , i think ?

main-qimg-f1fa99bc390f74e72e4d68b012a0158f.png

IMG_20200923_190929.jpg


While RBE 2 AESA use vivaldi.

I seriously don't know what type Uttam use ? But good thing is that's it's has notch radiators, rather than old slot, loop/ring.
 
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Swiftfarts

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View attachment 64133
Both Ku and X band AESA seeker use vivaldi(TSA).
I think X band AESA seeker is in use in QRSAM while KU band AESA is in use in ASTRA BVRAAM. :)
Ei-uYQ0UcAA6bsn (1).jpeg


If one look at TRM density in X band seeker above ^ . it has a 180mm diameter aperture size and has 84 radiating elements. Now if you scale up same configuration to say for SU 30 radar aperture of say 900mm how many TRM you can get ?

Seeker TRM density is probably less to avoid constructive and destructive interference + also to deal with power and cooling requirements. also vivaldi is basically two TRM packed in one so let's take it as a double . 84*2 > 168 elements ?

Since antenna size of a radar need to be comparable to it's wavelength and X band wavelength is between 2.5cm - 3.75cm.

We can calculate some good s**t here boys and girls. Thanks @Picdelamirand-oil from other forum to give us the equation to calculate TRM fill factor.

so here's the equation.

E = (4*A)/lamda ^2.

E = number of elements.
A= antenna physical area.

Since we know aperture size( diameter ) of major fighter jets , including Tejas , SU 30 , etc and Seeker above and there wavelength , we can calculate the hypothetical TRM fill factor.

180mm diameter antenna array give us around > between 72 minimum and 162 elements max. since the seeker has 84 we get a lamda of 3.48cm.

now for SU 30 with same lamda value as above as seeker ( 3.48 cm ) , with 90cm diameter aperture size.
we get a fill factor of around 2 ,100 TRM count :cruisin2: for our SU 30 god damnit.:balleballe:

I might be way off here with my calculations and scaling up so free to correct me.
Uttam gaya tel lenay this thing is what we need to scale up lmao!.
 

Swiftfarts

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So i did some more calculation , with same arrangement as X band seeker( lambda = 3.48 ) and got a fill factor for 60cm Aperture( diameter ) of Tejas as 930 TRM. That's more than Rafale :lol:

Well now i am pretty sure where's that increase in TRM count we keep hearing about for production version gonna come from :cruisin2:.

we know AN/APG 81 has a aperture size of 70 or 80cm or between , with 1676 TRM count. so we can calculate it's lamda which turn out to be around 3.46 if aperture diameter is 80cm and 3 if Diameter is around 70cm.
same as around that of X band AESA seeker , so look like we have achieved parity or are close to achieving one lol.
 
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Emperor Kalki

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This poster mentions anti radiation missile amongs the various weapons systems.
Is there any hele-compatible anti-rad missile in works.....any offshoots of any existing hele-launched missiles or anything....
Or is that just a mention of lch's anti-rad capability?
 

Dessert Storm

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Better to use HAL LUH for the project than older Cheetah helicopters.
Yeah. The learnings from the project can be applied to any platform, just like Maitri missile learnings were put to use in other systems.
That said, given that a working prototype is available, why not give it a try. If the economics work out, fine, otherwise use the learnings some place else.
 

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