I quote from the article Prasun’s referes to from FORCE Magazine in late 2006, titled “Flights of Fire“:
By late 2001 the DRDO had inked a comprehensive technologytransfer-cum-design rights buyout package with Radwar and PIT under which the DRDO would obtain and transfer the production technology for the PIT-developed TRS-17 S-band, 3-D radar with 240kmrange, and Radwar-developed N-22 Sband, 2-D 100km-range gapfiller radar, their respective antennae hoisting mechanisms, microwave line-of-sight signals relay antennae and related command-andcontrol consoles to the MoD-owned Bharat Electronics Ltd (BEL) who in turn would call them the Central Acquisition Radar (CAR) and the Battery Surveillance Radar (BSR).
While the CAR would be used along with a Group Control Centre for tracking up to 120 targets and providing fire-direction for up to three Batteries (each comprising four launchers, with each launcher carrying three missiles) of the Akash MSAM, the BSR and its Battery Control Centre will be able to track 72 airborne targets and will be linked to the BEL-built Rajendra target engagement radar, whose main antenna array will comprise 2,000 ferrite phase shifters and will be able to track 64 targets out to 60km, and engage four airborne targets simultaneously with 12 missiles. For the Army and Air Force variants of the Trishul SHORADS, the DRDO opted for Radwar’s S-band, 40kmrange 3-D mobile multi-beam search radar as the principal tactical early warning sensor.
Armed with these technology-transfer deals, the DRDO had by 2003 reinvigorated the Akash’s R&D phase and on 7 December 2005 conducted Akash’s 50th test-firing which, according to DRDL Director Dr Prahlada, was the first test-firing conducted with a fully functional Battery-level command, control and communications system.