| 摘要 |
PROBLEM TO BE SOLVED: To provide a GPS terminal for transmitting positional information with low power consumption, and in consideration of convenience and conditions on the management center side. SOLUTION: A CPU 12 performs control so as to prevent a communication module 13 from transmitting positional information obtained by a GPS receiving part 11 if the distance between its present position and its one-minute anterior position does not exceed a prescribed distance. If the voltage of a battery 15 is lowered to a prescribed value, the module 13 transmits the residual capacity of the battery 15 by storing it in positional information when the positional information is next transmitted. The management center 2 transmits a stop command to the GPS terminal 1 to stop the transmission function of the module 13. After that, the center 2 transmits a positional information request command to the terminal 1 only when positional information is wanted, and the CPU 12 causes the module 13 to transmit positional information only when this request command is received. COPYRIGHT: (C)2004,JPO
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