A fast algorithm for computing the transfer function for a nonuniform acoustic tube with acous
tical losses and branches has been developed. It is based on the derived analytical correlations between the
crosssection areas of such a tube and the coefficient of a corresponding autoregressive model with a moving average (ARMA model). Comparison of transfer functions calculated with the use of the derived correlations with the results of a standard transmissionline method shows the accuracy and efficiency of the developed algorithm.