Sisir Radar has achieved a significant breakthrough in the development of a miniaturised spaceborne Synthetic Aperture Radar system operating in the X band.

The team has successfully built a Design Verification Model featuring an unfurlable antenna, a technology that is both complex and critical for space applications. This milestone marks a major step forward in indigenous radar engineering.

The engineers have demonstrated the first version of a two‑metre diameter unfurlable antenna structure. The demonstration included both stowed and deployed configurations, showcasing the reliability of the design. The structural members of the antenna have been realised using Carbon Fibre Reinforced Polymer, a material chosen for its strength, lightweight properties and resilience in the harsh conditions of space.

The most challenging aspect of the project was the design and manufacture of the links that enable the antenna to unfurl smoothly and lock into place. After extensive effort, the team cracked this complex engineering problem.

The links have been realised through a combination of 3D printed parts and precision‑machined elements, ensuring both innovation and robustness in the final product.

A particularly noteworthy achievement is that all the links and edge elements were manufactured entirely in‑house. This demonstrates a high level of self‑reliance and technical capability, reducing dependence on external suppliers and ensuring complete control over quality and design. Such in‑house development is rare and reflects the maturity of Sisir Radar’s engineering program.

By successfully building this unfurlable antenna reflector structure from scratch, Sisir Radar has become only the third group in the country to achieve this feat, following the Indian Space Research Organisation and the Defence Research and Development Organisation. This positions the company among the elite in advanced radar and antenna technology development.

The unfurlable antenna is a critical enabler for spaceborne SAR systems, as it allows large aperture sizes to be deployed in orbit while maintaining compact stowed dimensions during launch.

This capability enhances imaging resolution and coverage, making the system highly valuable for earth observation, surveillance and strategic applications. The use of CFRP ensures durability against thermal cycling and radiation, while the precision links guarantee repeatable deployment in space conditions.

This achievement not only strengthens India’s technological base in advanced radar systems but also highlights the growing role of private and independent groups in contributing to national space and defence programs. The success of Sisir Radar in this domain reflects a broader trend of innovation and capability building beyond traditional government agencies.

Agencies