Tomographic Characterization of a Multifunctional Composite High-Impedance Surface

Abstract

The performance of a multi-functional composite high impedance surface (HIS) has been evaluated using the coherent Doppler tomography (CDT) and finite impulse response (FIR) filtering techniques. The HIS was fabricated using a combination of embroidery and advanced laser manufacturing processes. The result is a new conformable multi-functional glass fiber re-enforced polymer (GFRP) substrate suitable for structural load-bearing smart skin applications. The CDT method was utilized because it enabled the generation of a high resolution tomographic map of the HIS reflectivity. Tomograms generated at high incidence angles (> 80° from normal) were used to localize and FIR filter unwanted scattering associated with the ground plane edges and HIS transition regions. The resulting scattered fields from a defect (metallic block positioned in the center of the tomogram) were then used to assess the surface wave absorption within the HIS. Measured and simulated results are in excellent agreement.