A method for analysis of transmission line networks using frequency response approximation

In the method based on the discrete Fourier transform of transmission line networks, the number of frequency components to be considered depends on th e effective frequency of the network and the amount of time the input power supply is restricted. Hence, if the input power supply lasts a long time, many frequency components are needed and the computational efficiency is de graded, even if the effective frequency of the network to be analyzed is un changed. This is because the network equation needs to be solved every time in order to obtain the response at each frequency. In this paper, a method is proposed in which the solutions of the network equation are sought as f ew times as possible and the frequency response is approximate instead. As approximation methods, one based on the third-order spline function and one based on the discrete Fourier transform-inverse transform are used. Throug h numerical examples, it is shown that the proposed method is superior in t erms of computational efficiency to the moment matching method (known as a high-speed simulation method) for a relatively small-scale problem. (C) 200 0 Scripta Technica.