Indian Missile News And Discussion

[Arun_S]

[quote name='sumishi' date='02 October 2011 - 05:40 PM' timestamp='1317556966' post='113122']

[size="3"]Sirji, what is the link to that Agni article /blog / thread?

Thanks![/size]

[/quote]



Used to be on Bharat Rakshak, but couple of years ago I pulled out all my pages that constituted BR's missile section and also space section. Have been too busy to host it somewhere else after purging all BR watermarks in my diagrams.



I some web archiving sites still have those articles.



My first article on Indian Defense Review (IDR) was also re-published on BR's SRR (Security Research Review) available [url="http://www.bharat-rakshak.com/SRR/Volume13/sanjay.html"]online[/url] {This article was largely a subset of my Agni web page on BR. Sanjay's contributing to contwnt was minor, he did some editing, and but he used his name first but that did not bother me}.

Avionics, Navigation and Control



The Agni family of missiles uses a strap-down INS system for flight control and navigation.



The Agni introduced a new concept by adopting MIL-STD-1553 databus for all on-board communication and control device interconnections (mainly INS system, Flight Control Computer, actuators and sensors).41 It is the standard that is adopted in new civilian and military aircraft (circuit routing and device mounting) and all the software in the Agni-II has been designed around this bus. DRDO sources claim that this reduces the number of connections and also making the missile more rugged. However, some missile analysts feel that a standard databus may not be the best path to follow. It is said that a customised databus is better because in a standard databus, one tends to use off-the-shelf electronic devices whose performance may not be optimal. However, most modern missiles are moving towards digital buses using commercial off-the-shelf technology, which enables affordable sub-system replacement or enhancement.



Accuracy



[color="#800080"]Agni-II navigation and aiming utilises an advanced ground based beacon system using TDOA (Time Delay Of Arrival) technique similar to GPS42 that constantly provides missile flight position and velocity update that has been proven in test flights.43 The TDOA system reportedly improved the accuracy by three times.44[/color]



India has demonstrated a measure of mastery in navigation sensors and flight control through its space programme. The placement accuracy in GTO (involving powered flight of 1,000 seconds, much of it in sub-G or gravity free environment) is a far more complicated and delicate matter45 than that of the sub-orbital trajectory of an IRBM. Thus the GSLV-D2 and GSLV-F01 GTO Apogee accuracy of 1965 PPM46,47 and 361 PPM48,49 respectively, compares with Agni-II’s 40 metres CEP at IRBM range with 13 PPM accuracy.

Of course this is also on Wikipedia's Agni page, that got much of its present content from my updating the Wiki page.



The highlighted sentence has been since then referred and incorporated in may web articles on Agni missile since then. As Googling will show.