India's Radar Revolution: DRDO Seeks Partner for Next-Gen AESA Radar Development

India's Defence Research and Development Organisation (DRDO) has taken a significant step towards strengthening its indigenous radar expertise by issuing a Request for Proposal (RFP) for the development of a cutting-edge 256-element X-band Active Electronically Scanned Array (AESA) radar panel.

The DRDO's latest RFP marks a major milestone in India's efforts to develop and integrate advanced radar technologies, which are critical components of modern military systems. The programme seeks an industry partner capable of designing and developing a complete radar array architecture comprising modular transmit/receive (T/R) boards, liquid-cooled antenna panels, mechanical structures, and associated test infrastructure.

At the heart of the programme is the development of a 256-element flat panel antenna array operating in the X-band frequency range of 8.5–10.5 GHz. The array will consist of 256 radiating elements arranged in a 16×16 configuration, utilising 256 independent transmit/receive (T/R) channels to enable precise electronic beam steering without the need for mechanical movement.

A key feature of the proposed design is its modular architecture, based on scalable 8×8-element T/R circuit (TRC) boards. Each module will contain 64 radiating elements and associated T/R electronics, allowing multiple modules to be integrated into a larger flat-panel radar. This modular design simplifies manufacturing, testing, maintenance, and future upgrades while allowing the technology to be adapted for radar systems of varying sizes and applications.

The RFP also calls for the development of several critical supporting subsystems, including the TR printed circuit boards (PCB), antenna array panels, liquid-cooled cold plates, mechanical enclosure, radome, and dedicated test jigs. These components are essential for creating a fully integrated radar panel capable of reliable operation under demanding environmental and thermal conditions.

Thermal management forms one of the most significant aspects of the programme, with the 256-element array expected to consume approximately 2.6 kW of electrical power and dissipate around 2.2 kW of heat at a 20 percent duty cycle. To manage this thermal load, the DRDO has specified an integrated liquid-cooling system using cold plates, ensuring stable operation of the high-power T/R modules while maintaining radar performance and reliability.

Each individual 8×8 T/R module is specified to consume up to 650 watts while dissipating approximately 550 watts of heat, also requiring liquid cooling. These modules will serve as the fundamental building blocks of the complete radar array and demonstrate the scalability of the architecture for larger radar systems in the future.

Performance specifications outlined in the RFP indicate that the radar panel should achieve a 3 dB beamwidth of approximately 3.5 degrees, support electronic scanning of ±60 degrees in azimuth and ±60 degrees in elevation, and generate an output power density of approximately 0.3 microseconds pulse width at a 20 percent duty cycle. The array is also required to maintain a system noise figure of approximately 3.5 dB, enabling high sensitivity for target detection.

The interface requirements include operation from a 28±2 V DC power supply, with control and timing signals handled through LAN and LVDS interfaces. RF connectivity will be provided using SMP connectors, supporting all 256 transmit/receive channels along with calibration interfaces. Such specifications suggest compatibility with modern digital radar architectures and high-speed signal processing systems.

Although the RFP does not identify the intended platform, flat-panel AESA arrays of this class have broad applicability across multiple defence domains. X-band AESA radars are widely employed for fire-control radars, airborne surveillance, naval radar systems, missile seekers, tracking radars, and multifunction sensor suites. Their electronically steered beams allow rapid target acquisition, simultaneous multi-target tracking, and high-resolution imaging while offering greater reliability than mechanically scanned antennas.

The modular 8×8 architecture specified by the DRDO could also facilitate the development of larger radar apertures by combining multiple panels, enabling a common technology base for a range of military applications. Such an approach reduces development costs while simplifying logistics and maintenance across different radar programmes.

The RFP reflects the DRDO's continued focus on strengthening indigenous expertise in critical radar technologies, particularly in high-performance T/R modules, thermal management, advanced packaging, and scalable antenna architectures. These technologies form the backbone of modern AESA radars, which are increasingly becoming standard equipment on fighter aircraft, warships, ground-based air defence systems, and advanced surveillance platforms.

The development of this cutting-edge 256-element X-band AESA radar panel will not only enhance India's indigenous radar capabilities but also contribute to the country's efforts to become a major player in the global defence industry. As the DRDO continues to push the boundaries of radar technology, it is likely that this programme will have a significant impact on the country's military modernisation efforts and its ability to counter emerging threats in the region.