A Fractional Derivative Operator for Surface Impedance TLM Modeling

A new and straightforward implementation of metallic losses in a time-domain field computation namely, the transmission line matrix (TLM) is presented. The approach is based on the description of the skin surface impedance concept directly in time-domain by means of a digital filter representing a fractional derivative operator. Numerical implementation based on recent advances in signal processing is shown. Finally, the new approach is tested and compared to usual TLM implementation showing the stability and accuracy of the scheme.