Patent ID: 8611831

Claim:
A transmission device, comprising: N number of transmitting units for transmitting predetermined information by radio waves of identical frequency each time that a given time T elapses, wherein each of the transmitting units have; an information storage component configured to store, from among preset numbers from 1 to N representing a transmission sequence, a numeric value N, as well as a numeric value unique to the unit, which is different from numeric values stored in other of the transmitting units; a trigger value determining component configured to, when a value obtained by subtracting 1 from the numeric value unique to the unit is positive, store the subtraction result as a trigger value, or when the subtracted value is negative, store the value of N as a trigger value; a receiver configured to receive radio waves of the frequency; an at-startup transmitter configured to transmit the numeric value unique to the unit and the predetermined information when the numeric value unique to the unit is 1 at startup; a detector configured to detect the numeric value from a radio wave signal received by the receiver; a clock configured to clock time elapsed after the detected numeric value matches the trigger value; and a transmitter configured to transmit the predetermined information and the numeric value unique to the unit when the elapsed time clocked by the clock matches a predetermined time t that is less than the given time T.