Analysis of transmission lines with frequency-dependent parameters by wavelet-FFT method

A wavelet approach to the analysis of transmission lines equations with frequency-dependent parameters is presented. The transmission line equations in the frequency domain are expanded on a wavelet basis, yielding an algebraic system in the wavelet-frequency domain. The algebraic system is then solved by the use of standard techniques; the results are inverse transformed yielding the behavior of voltage and current all along the line in the frequency domain. Inverse fast Fourier transform gives the time domain solution. The convenience of using the wavelet transform is that the matrices are sparse and of lower dimension if compared to standard techniques. The proposed method is characterized by low CPU times and low memory consumption.