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porky_kicker

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Similar mast systems are already operational

4788731_homekanpurnewsphoto98a47f7thumb_jpeg0fb0025039bf92e1eedefd22326a92e0.jpg


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The one above is already deployed with BFSR-MR ( and possibly similiar masts for LORROS also exists )

And I read the additional materials posted from the tender in the twitter thread. It mentions a 5 m main reflector , a sub reflector , a feed horn and a mirror mechanism .

EvkQzxBUUAMgXtm.jpeg


This indicates a cassegrain antenna which is generally used for satellite communications , but is also used for land communication .

Using a elevating mast for cassegrain antenna doesn't make sense if it is for satellite communication , therefore It could be for land communication over long distances because such antennas have good directivity and low loss .

Now comes the intriguing part , the docs mentions a mirror assembly which is located behind the main reflector and the feed horn is positioned perpendicular to it ( also behind the main reflector ).

EvkQzxAU4AEIB5r.jpeg


AFAIK In a cassegrain antenna the feed horn lies directly behind the main antenna along the axis of the sub reflector. The introduction of the mirror mechanism and shifting of the feed horn away doesn't make sense and for what ?

Is it for some kind of system for optical transmission ? I don't know. Feed horn is mentioned , but what kind is omitted . AFAIK Optical feed horns exists.

I don't have enough knowledge to comment on the same.
 
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fire starter

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Similar mast systems are already operational

View attachment 80362

View attachment 80363

The one above is already deployed with BFSR-MR ( and possibly similiar masts for LORROS also exists )

And I read the additional materials posted from the tender in the twitter thread. It mentions a 5 m main reflector , a sub reflector , a feed horn and a mirror mechanism .

View attachment 80366

This indicates a cassegrain antenna which is generally used for satellite communications , but is also used for land communication .

Using a elevating mast for cassegrain antenna doesn't make sense if it is for satellite communication , therefore It could be for land communication over long distances because such antennas have good directivity and low loss .

Now comes the intriguing part , the docs mentions a mirror assembly which is located behind the main reflector and the feed horn is positioned perpendicular to it ( also behind the main reflector ).

View attachment 80367

AFAIK In a cassegrain antenna the feed horn lies directly behind the main antenna along the axis of the sub reflector. The introduction of the mirror mechanism and shifting of the feed horn away doesn't make sense and for what ?

Is it for some kind of system for optical transmission ? I don't know. Feed horn is mentioned , but what kind is omitted . AFAIK Optical feed horns exists.

I don't have enough knowledge to comment on the same.
Since when LRDE started developing communication system.
 

porky_kicker

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not possible IMHO iskander is a quasi ballastic missile and barack 8 missiles do not hve speed to intercept the missiles
Eh?

Interception occurs head on or in tail chase mode for ballistic / quasi ballistic targets ?

Is there any interceptor in existence which can chase a ballistic or quasi ballistic missile traveling from anywhere between 5 Mach to 30 Mach ?

Interception occurs in head on mode or in the lateral cross over mode. All that is required is the necessary speed to position the interceptor on the path of the incoming missile at the exact moment when they will in close proximity ( for proximity warhead detonation ) or hit each other ( for hit to kill warhead ).
 

porky_kicker

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Since when LRDE started developing communication system.
I gave my views based on the tender material . Which lab is doing what , I am not concerned . And what I wrote is a best guess from me and I could easily be wrong.

Just for the sake of discussion

You could ask why would lrde a radar establishment would come up with something like this for a radar ?

AddText_03-04-05.04.42.jpg


Do you know of any radar which has a mirror mechanism along the focal axis of an antenna and the feed horn aligned perpendicular to the focal axis behind the main reflector ? ( If the feed horn is behind the cassegrain antenna , it lies axially along the focal axis [ in the pic Z direction ] )

I personally know of none, not much into these antennas/radars, amateurish knowledge at best.

Anyways it could be for communication , or for testing or for calibration or a radar ( which I personally doubt )

But I will be happy to be proven wrong.
 
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fire starter

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I gave my views based on the tender material . Which lab is doing what , I am not concerned . And what I wrote is a best guess from me and I could be wrong also.

Just for the sake of discussion

You could ask why would lrde a radar establishment would come up with something like this for a radar ?

View attachment 80370

Do you know of any radar which has a mirror mechanism along the focal axis of an antenna and the feed horn aligned perpendicular to the focal axis behind the main reflector ? ( If the feed horn is behind the cassegrain antenna , it lies axially along the focal axis ).

I personally know of none, not much into these radars, amateurish knowledge at best.

Anyways it could be for communication , or for testing or for calibration or a radar ( which I personally doubt )

But I will be happy to be proven wrong.
Good read regarding optical horn antennas.
 

fire starter

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Do you guys know of Indian communication system which act as secondary back ups incase of nuclear strike ie able to operate despite heavy EM interference post nuclear strikes.
Which ? I remember u hinted about it few yrs ago. Is it based on laser?
 

porky_kicker

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Dual stage? And which missile it will be used.
To be fair , I wanted to edit the post , but time to edit had expired.

I was not able to 100% ascertain if the one in the pic is concrete penetration warhead. I give 50/50 chance.

There is also the multistage warhead in development whose pic I posted
already.

And I wonder what's the status on this one , it is definitely for targeting HDBTs.

Ad3-04-06.02.17.jpg


I suspect news regarding the above will never be released.
 
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