摘要 |
Numeric values "a" representing a respective order of transmission by a plurality of transmitting units, and a numeric value N representing the total number of transmitting units, are set for each of the transmitting units. At startup, a transmitting unit for which the value "a" representing the order of transmission of the unit has been set to 1 sets a trigger value to N and transmits information about the value "a" of the unit and detection information from a sensor, and, when the value N is detected from a received signal, transmits the value "a" of the unit and detection information. When a value of a-1 is detected from a received signal, the transmitting unit for which the value "a" representing the order of transmission of the unit has been set to other than 1 transmits the information of the value "a" of the unit and detection information. |