On the validity of the homogeneous lattice model for the calculation of the surface resistivity of a granulated superconductor

Propagation of electromagnetic wave in high-temperature superconducting ceramics is considered in terms of disordered solid medium which effective characteristics are calculated. Possibility to describe superconducting ceramics using homohgeneous lattice model to estimate surface impedance at ultra-high frequencies is shown. This model is shown to be satisfactory one in application field of ceramics continuous description