Modeling and measurement of target-string interactions

One method of supporting a target during a radar cross-section (RCS) measurement is to suspend the target from strings. Even for electrically small diameter strings, significant specular backscattering is produced when a string is oriented perpendicular to the radar illumination. This contamination, often referred to as string "flash", is clearly evident in measurements of string-supported targets. Specular scattering due to indirect, target-dependent illumination of the support strings is frequently not considered. This can result in significant target-support interaction (TSI) contamination. We modeled and measured this multiple scattering interaction as part of an on-going effort to assess the impact of TSI on RCS measurements.