Resonant Behavior Measurements and Two-Dimensional Imaging of Small Conducting Spheres in Catr

Abstract

Based on swept frequency RCS measurement system, low density foam column and proper data processing procedure, the resonance curves of conducting spheres with RCS below −32.95 dBsm are achieved in a single reflector Compact Antenna Test Range (CATR), with the measurement errors less than 1.0 dB over most of the measurement frequencies. Nine spheres down to −49.01 dBsm are clearly imaged with Range-Doppler (R-D) method and pointwise vector background subtraction technique.

A fast and robust method for target and background estimation in RCS measurements based on ‘hyperaccurate’ algebraic circle fit

“…In order to gain high accuracy of measurement, many clutter and noise reduction techniques have been implemented [2]. Among of them the most usual one is called background or "coherent" subtraction [3], [4]. However this method will lose its effect when the inhomogeneity of the foam support and the shape change of the low-scattering metal pylon cannot be neglected.…”

An Accuracy Method of Extracting Background Clutters

“…Therefore, how to improve the accuracy of removing the clutter becomes priority among priorities [4] . The traditional method called background or "coherent" subtraction is shown in paper [5,6] . Back to 1996 year, Morgan applied the linear least median squares(LMS) algorithm [5] to acquire background signal.…”