By Lawrence Williams, PhD., Director Product Management, Matthew Commens, PhD., Product Manager, HFSS, and Steve Rousselle, Technical Director, ANSYS, Inc.
Advances in modern radar systems include specialized active antennas, microwave circuits and devices, agile beam steering and shape, and digital space-time signal processing. While the pace of radar technology continues to march forward, two fundamentals remain constant. The first is that the electromagnetic properties of antennas, radomes, and the installation platform are governed by the underlying and unwavering physics. The second is that engineers designing these systems will push the limits of simulation, based on that underlying physics, to solve ever-larger and more complex electromagnetic radiation and scattering problems. While the physics does not change, the numerical methods engineers and scientists apply continues to advance, built upon the fundamental principles and theorems of electromagnetics.
The technological needs of the radar system designer or antenna designer are to provide understanding of the radiation and scattering performance. A phased array radar antenna, for instance, does not operate in free-space. On the contrary, it may be mounted on the front or side of an aircraft. That aircraft is likely constructed of both metallic and composite materials. The antenna is covered by a radome that likely contains a frequency selective surface (FSS). Understanding the radiation and scattering performance of such a system requires a very comprehensive simulation capability.