Rajendra is a C-band passive electronically scanned array (PESA) multi-function fire-control radar developed by the Electronics and Radar Development Establishment (LRDE), DRDO, serving as the engagement/tracking radar for the Akash surface-to-air missile system. Derived conceptually from the Rajendra family of phased-array radars developed for India’s air defence needs, it is one of the earliest indigenous phased-array radars fielded operationally by the Indian armed forces.[1]
Rajendra uses a passive phased array of roughly 4,000 discrete radiating elements to electronically steer its beam without physically moving the antenna, enabling rapid multi-target search, track and engagement support. Mounted on a mobile launcher-adjacent platform (typically alongside a battery of Akash launchers), a single Rajendra radar can simultaneously track up to 64 targets and provide guidance data to engage as many as four targets at once via the Akash missile’s command-guidance uplink.[1][2]
The radar provides detection and track coverage against targets of roughly 2 m² radar cross-section from about 4 km out to 80 km, and against altitudes from as low as 30 m up to 20 km, with a transmitted power rated at 70 kW or greater. Being the fire-control element of the Akash system, Rajendra’s tracking accuracy and multi-target handling directly determine Akash battery engagement capacity.[1]
An upgraded “Rajendra Mk-II” variant with improved processing and an extended engagement envelope has been associated with the Akash-NG and later Akash upgrade programmes. The core Rajendra design philosophy — a mobile PESA fire-control radar tightly coupled to a mobile SAM battery — has informed subsequent LRDE fire-control radar work.[2]
| Type | C-band passive electronically scanned array (PESA) fire-control/engagement radar |
| Developer | LRDE, DRDO |
| Role | Fire-control radar for Akash SAM system |
| Array elements | ~4,000 discrete radiators |
| Detection range | 4–80 km (≥2 m² target) |
| Altitude coverage | 30 m – 20 km |
| Power | ≥70 kW |
| Simultaneous tracks | Up to 64 |
| Simultaneous engagements | Up to 4 targets |