Ultra-Low-Cost Radar Cross Section Measurement and Validation Method Using a 3D-Printed Scale Model in a Non-Anechoic Chamber Environment

This paper validates the accuracy of radar cross section (RCS) measurements conducted in an environment that significantly reduces the three main costs associated with RCS measurements: spatial costs, target under test (TUT) production costs, and the costs of constructing and maintaining an anechoic chamber. Measurement results for simple shapes that satisfy far-field conditions, such as metal spheres and metal plates, are presented. Additionally, results are provided for a geometrically complex 1/15 aircraft scale model that does not satisfy far-field conditions. The noise equivalent RCS (NERCS) of the proposed non-anechoic chamber setup is determined by measuring various sizes of metal spheres, and the RCS error over time is evaluated by measuring a metal plate continuously for 12 h in a non-temperature and humidity-controlled environment. The NERCS is found to be -43.2 dBsm. The mean RCS error for the metal plate, measured immediately after background measurement and again after 12 h, is found to be 0.005 dB and 0.220 dB, respectively. For RCS measurements of the 1/15 scale model, an image-based near-field to far-field transformation (NFFFT) algorithm is employed. The NFFFT results, including image filtering, show a mean RCS error of 5.6 dB. This error is 1.9 dB higher than previously reported results obtained in an anechoic chamber environment using an amplifier to enhance the signal-to-noise ratio (SNR). These findings can serve as guidelines for considering measurement results in a highly simplified RCS measurement setup, offering rapid feedback crucial for stealth platform design.