To easily realize a device by subtracting an interference replica signal of its own user from an interference replica signal from other user and giving the difference to an interference cancel unit so as to reduce a transmission speed for a part through which an interference replica signal of other users is propagated for each user.

An ICU 13 at 1st stage of each user sends an interference replica signal generated by an ICU#1-1 to an ICU#1-2, from which the signal is sent to a succeeding adjacent ICU#1-3 together with a replica signal generated in the ICU#1-2. Then the signal is processed similarly up to a final ICU#1-k, and sum of interference replica signals generated at them is sent to a succeeding stage. Simultaneously the interference replica signals generated by IC13 of each user are sent to a subtractor 17 via a transmission line 16. By using this method, the transmission speed of the interference replica signal to be informed to each user is enough to be the same as the interference replica signal by one user even when number K of users and number of stages N are increased.