Measured and FDTD Calculated Ultra Wide Band (UWB) RCS for treated test fixtures

This paper presents comparisons of measured, and finite difference time domain (FDTD) calculations of ultra wide band scattering for dimensionally scaled, shaped and treated fixtures and measurements on a ground plane fed by vertically polarized TEM horn antenna operating from 50 MHz to 18.05 GHz. Method of moment (MoM) calculations are used to cross-check measurement and FDTD. UWB exotic material effects should be more easily observed at low scattering levels. Our findings indicate that for multiple target characteristics and over UWB bandwidths, FDTD code furnish a sufficient level of predictive accuracy (i.e. -30 to -40 dBsm) such that it might be applied in RCS predictions of treated targets where exotic RF - material interactions resulting from high power UWB waveforms might be used. RCS predictions could then be applied to improve signal processing algorithms. The paper discussed measurement technique, choice of fixtures, FDTD model, the measurement-model level of agreement and outlines a path to verification.