Аннотация:We examine a new method for the calculation of the traveling wave characteristic in a layered medium. The seismic impedance tensor method is improved by introducing the notion of a potential function and new iterative relationships are obtained for isotropic layered media. Comparison of the dispersion equation roots between the generalized reflection-transmission coefficient method (GR/TC) and the seismic impedance tensor method (SIT) has detected some roots that do not exist in SIT. To check the accuracy of the roots in both methods, we have compared the experimental results between the classical transition matrix method (Thomson-Haskell) and our new method (SIT) for the same layered medium model. The experimental results show that the roots obtained by the impedance method coincide with the classical transition matrix method. This also shows that some roots obtained from the dispersion equation in GR/TC cannot be accurately determined.