Multistep Cylindrical Structure Design for Wideband Radar Cross Section Reduction at Normal Incidence

A wideband radar cross section (RCS) reduction measure applicable to rod-like targets is proposed. This technique uses the differences in radii among multistep cylindrical structures to create a phase reversal for backscattering cancelation. In order to broaden the reduction bandwidth, a simple one-step design is evolved into a multistep one using the binomial expansion method. Its superior performance is verified via numerical simulations based on the physical optics (PO) and full-wave method. Under normal incidence, a 2.45:1 bandwidth ratio is achieved for more than 20-dB RCS reduction with a five-step design. Effects of critical design parameters such as the number of steps and the cylinder displacement order are examined. This approach can be employed on rod-like defense targets. A series of simulations that emulate a periscope protruding from the sea surface is conducted to demonstrate the applicability of the proposed technique.