PURPOSE: To extend remarkably the transmission range by operating aonly a terminal equipment having the closest address to its own address in a signal as a repeater among terminals having addresses between one's own addresses and destination addresses in the sent signal.

CONSTITUTION: Assuming the sent one's own address as M and the destination address as N, when M<N-1, a terminal equipment having the address M+1 is operated to store tentatively a sent voice message, its own address (M+1) and the destination address 'N' are sent and the recorded voice message is reproduced and sent. The corresponding terminal equipment repeats sequentially the repeating transmission while its own address is incremented by one in such a way. When the relation of M>N+1 exists, the terminal equipment having an address M-1 applies repeating transmission, and its own address M-1 and the destination address N are sent. Then the corresponding terminal equipment repeats sequentially the repeating transmission while its own address is being decremented by one.