LOCATION MESSAGING SYSTEM USING GPS

A GPS receiver communicates with a management center through a portable telephone terminal. The management center is connected to a telephone unit and a facsimile unit in a house through a telephone line. When the user presses a predetermined button with the telephone unit, a request for location information of the receiver is transmitted to the management center. The management center transmits the location information request as a DTMF signal to the receiver. The receiver measures the location thereof. The measured result and time information of a navigation message thereof are transmitted as a DTMF signal. When the management center determines that the message is old corresponding to the time information, the management center compensates the measured result. The management center transmits the location information to the telephone unit. The management center transmits image data with map information to the facsimile unit.