| 摘要 |
PURPOSE:To prevent a battery from being consumed unnecessary by turning on and off the power source of a receiver according to the entry and exit of an individual into and form a monitor area. CONSTITUTION:Transmitting and receiving terminal equipments (SR) 211-2nl sends electromagnetic waves of specific frequencies repeatedly at a constant period for a specific time according to a command from a center equipment (CTE) 5, and receive answer signals from individual bodies 71-7m which are possessed by the individual in respective rooms 11-1m. The power sources of the individual bodies 71-7m are turned on in synchronism with the fixed period transmission, and at the time the transmission individual bodies 71-7m are turned off. Accordingly, power source of the IDs 71-7m are on-off controlled according to the entry and exit of the individual into and from the respective rooms 11-1m. |
