The Indian Air Force (IAF) is set to enhance its air surveillance and defence capabilities with the procurement of 18 Ashwini Low-Level Transportable Radars (LLTRs). The Ministry of Defence has signed a contract worth Rs 2,906 crore to acquire these state-of-the-art radar systems, which will play a crucial role in bolstering the nation’s air defence network.
 |
| LLTRs Ashwini |
Overview of Ashwini LLTR
Ashwini LLTR is an indigenous rotating active phased array multifunction 4D radar developed to provide automatic detection and tracking of aerial targets. It is capable of detecting a wide range of airborne threats, including fighter aircraft and slow-moving targets. The radar boasts an impressive instrumented range of 200 km, with the ability to detect a target with a radar cross-section (RCS) of 2 square meter at a distance of 150 km. Its altitude coverage extends from 30 meters to 15 km.
The radar operates in two modes:
Rotation Mode: The antenna rotates at 7.5/15 rpm, providing 360-degree surveillance in azimuth and 40-degree coverage in elevation.
Staring Mode: The antenna is fixed in a specified azimuth direction with a ±60-degree azimuthal coverage and 40-degree elevation surveillance.
Built on solid-state active aperture phased array technology, the radar employs Digital Beam Forming (DBF) for enhanced electronic scanning in both azimuth and elevation. Wide transmit beams and multiple receive beams ensure optimal target tracking and detection.
Advanced Technologies in Ashwini LLTR
The development of Ashwini LLTR has led to the establishment of several critical technologies, paving the way for future radar projects. These include:
Rotating Active Phased Array with time synchronisation of multiple receivers
2D Digital Beam-Forming (DBF)
DBF-based active array calibration
Multi-beam processing
Critical real-time software and firmware development
Advanced mechanical packaging, including thermal management and structural engineering
IAF's Need for Ashwini LLTR
Ashwini LLTR addresses a crucial need of the IAF by eliminating radar blind spots caused by terrain. This highly mobile radar system can detect objects moving at 1 km/sec at an altitude of 15 km. It provides impressive detection ranges: 200 km for targets with an RCS of 2 sqm and 50 km for smaller targets with an RCS of 0.2 sqm. Moreover, it has the capability to track up to 200 targets simultaneously, making it a critical asset for air defence operations.
 |
| Target Tracking HMI display |
Application Areas
The Ashwini LLTR technology is versatile and can be adapted for various military applications, including shipborne radar systems. Its advanced detection and tracking capabilities make it a vital component for naval and land-based defence installations.
Successful Field Trials
The first phase of field trials for Ashwini LLTR in an integrated mode was successfully completed in 2019, demonstrating its effectiveness and reliability. The successful trials marked a significant step towards its deployment in the IAF, ensuring robust airspace surveillance and threat detection.
The procurement of Ashwini LLTRs is a significant leap in strengthening India’s air defence capabilities. With cutting-edge technology, high mobility, and advanced target tracking features, these radars will play a crucial role in securing the country’s airspace. As the system gets inducted into the IAF, it will serve as a force multiplier, enhancing situational awareness and air defence operations across diverse terrains and operational scenarios.