CHANDIGARH: A team of researchers at Indian Institute of Technology, Mandi, in Himachal Pradesh
has developed a new ‘signal absorber’ technology that can make defence equipment and civilian applications invisible to radar. They have created an artificial material that can absorb a wide range of radar frequencies, irrespective of the direction from where the signal hits the target.
It can be used to cover windows or glass panels of stealth vehicles and covert establishments that need to be made invisible to radar. Talking about the research, Dr G Shrikanth Reddy, assistant professor, School of Computing and Electrical Engineering at IIT Mandi, said, “We have developed a technology based on Frequency Selective Surface (FSS) that absorbs a wide range of frequencies used in radar, making the surface invisible to radar.
The proposed design uses an optically transparent ITO-coated PET sheet wherein the FSS patterns are created on this PET sheet. The FSS patterns on the PET sheet were created with laser engraving technology, and due to symmetrical nature of FSS patterns, the proposed absorber is polarization insensitive and absorbs a wide range of EM wave frequencies within C, X and Ku Band.”
Radar Cross Section (RCS) reduction is a way to make something less visible to radar. It is achieved by using materials that can absorb radar signals, or by shaping the object in a way that makes it difficult for radar to detect. He added that tests have shown that this FSS technology can absorb over 90% of the radar waves in a wide range of frequencies. The team performed experimental studies on their design and the results matched well with the theoretical analysis, verifying its effectiveness.
“This technology can be used on window or glass panels of stealth vehicles and covert establishments due to its optical transparent nature. The team has already developed a prototype. It has potential applications for RCS reduction and absorption of unwanted radiation leakages,” Reddy said.
Radar-absorbing materials play a crucial role in defence applications as they are used to reduce or eliminate the radar signature of military aircraft, ships and vehicles, according to sources. They can also be used to protect critical infrastructure such as communication towers, power plants and military bases from radar detection. This can prevent non-friendly entities from targeting important facilities. The work has been published in the journal, IEEE Letters on Electromagnetic Compatibility Practice and Applications, co-authored by Reddy and his team, Dr. Awanish Kumar and Jyoti Bhushan Padhi.
Signal Absorber
IIT Mandi researchers develop artificial material that can absorb a wide range of radar frequencies, irrespective of the direction from where the signal hits the target
‘Signal absorber’ technology can make defence equipment and civilian applications invisible to radar’
Technology based on Frequency Selective Surface (FSS) that absorbs radar frequencies. Proposed design uses optically transparent ITO-coated PET sheet, on which FSS patterns were created with laser engraving technology
Proposed absorber is polarisation insensitive and absorbs a wide range of EM wave frequencies within C, X and Ku Band
Technology can be used on window or glass panels of stealth vehicles and covert establishments