Wednesday, May 24, 2017

New M.Tech. Thesis Submitted from Electronics

DESIGN AND OPTIMIZATION OF RADAR ABSORBING MATERIAL WITH THE HELP OF RESISTOR FSS by Ravinderjit Kaur

Abstract
RADAR absorption materials (RAMs) and coatings have been widely used in stealth technology since World War II. Stealth refers to the ability to evade from the detection from any kind of radar detection. Radar absorbing materials have found a significant importance in today’s stealthy technologies to make the combat aircrafts or drones electromagnetically invisible to the radar detectors. So a combat aircraft can be useful in the war field only if it is not detectable by sensors and moreover the capacity load it can hold to carry maximum armed forces and ammunitions. Therefore, numerous research works have been done to pursue a high-performance absorber to solve the electromagnetic pollution problem. Earlier different types of paints were used to coat the surfaces of the aircrafts, also known as black body paints. But paint not only used to make the aircraft heavier but would also incur unnecessary costs. With the advancement it has been invented that instead of painting the surface, the surface itself be made up of radar absorbing material. Various designs were also proposed in this regard but of hardly any use, as they also were not able to reduce detection to great extent. Then with further advancement it has been invented that the frequency selective surface embedded in the layers of radar absorbing material has better absorption than the normal ones. But
till now the proposed different geometric structures or the use of lumped elements in the material so far has one or the other limitation. So this work has been proposed to find the best trade off between the maximum absorption bandwidth and minimum material thickness with the use of particle swarm optimization and also compares the results of with and without lumped elements. The proposed comparison and results of optimization are in good agreement.