Improvement on RCS reduction using flat lossy focusing reflectors

Area of Science:

• Electromagnetics and Applied Physics
• Materials Science

Background:

• Subwavelength gratings are crucial for manipulating electromagnetic waves.
• Existing periodic gratings have limitations in controlling scattered fields.
• High absorptivity is a key requirement for advanced electromagnetic applications.

Purpose of the Study:

• To propose a novel planar non-periodic subwavelength resistive grating (SWRG).
• To demonstrate complete manipulation of scattered field phase fronts.
• To achieve high absorptivity while enhancing radar cross section reduction.

Main Methods:

• Design and simulation of a planar non-periodic subwavelength resistive grating.
• Analysis of scattered field properties, including phase front manipulation and focusing.
• Comparison of performance with periodic grating counterparts.

Main Results:

• The non-periodic SWRG allows complete control over scattered field phase fronts.
• The SWRG exhibits focusing properties akin to a resistive concave reflecting lens.
• Achieved up to 22.86 dB improvement in radar cross section reduction in the boresight direction compared to periodic designs.

Conclusions:

• Non-periodic design of SWRGs offers superior control over electromagnetic scattering.
• The unique focusing property enhances radar cross section reduction capabilities.
• This technology has significant potential for stealth, aerospace, and microwave anechoic chamber applications.