An input receiving section 102 of a transmitter apparatus 101 receives inputs of multiple synchronized signals r.sub.1, . . . , r.sub.N, an asynchronizing section 103 outputs multiple asynchronized signals v.sub.1, . . . , v.sub.N that are obtained by delaying the multiple synchronized signals r.sub.1, . . . , r.sub.N by time t.sub.1, . . . , t.sub.N, a modulating section 104 modulates the multiple output asynchronized signals v.sub.1, . . . , v.sub.N to output modulated signal w.sub.1, . . . w.sub.L (1.ltoreq.L.ltoreq.N), a transmitting section 105 transmits the output modulated signal w.sub.1, . . . w.sub.L, and the delay time t.sub.1, . . . , t.sub.N is shorter than a reciprocal number of a minimum value of clock rates of the multiple input received synchronized signals r.sub.1, . . . , r.sub.N, and is desirably proportional to one generated by a chaos random number in particular.