AbstractRecently a few studies have been made of distributed coupled‐line type digital frequency multipliers which multiply the repetition frequency of a square input wave. the transfer functions of an n‐section distributed coupled‐line constant‐resistance network and an n‐section distributed‐constant bridged‐T network have the form of a rational function of order n with respect to delay operator z−1. We develop our discussion on the basis of this transfer function. the theory is developed for the coefficients of the rational function and the output response in a stationary state can be determined by the coefficients of both the denominator and numerator. the obtained results can be applied to all networks having the transfer functions treated in this paper, but the detailed realization condition for each individual network is not discussed. the experiments and calculations shown in Figs. 4 ‐ 7 are conducted using the distributed coupled‐line constant‐resistance network as an application example. the network described here can be a digital frequency multiplier for two incident impulse trains, 1111 and 1‐11‐1. the behaviors of the multiplier in the frequency domain as well as in the time domain are investigated and it is shown that a faster impulse train can be obtained at the output in the time domain by adequately thinning out the discrete frequency components of t