This paper presents a study of the dielectric properties of radar absorbent materials (RAMs) for use at X- band. Two different RAMs with different conductivities were prepared from the conducting polymer polyaniline. The RAMs were characterized with respect to their absorption and reflectivity to electromagnetic waves, and electric permittivity. The evaluated materials attenuated the energy of the incident radiation from 30 to 65%. A hybrid optimization algorithm (HA) was used to find the optimal parameters for these materials for processing. The results obtained by the HA are in good agreement with experimental measurements.