Patent ID: 6662013
Filing Date: 2003-12-09
Classification: G01S,H04B

Abstract:
A GPS receiver for receiving navigation messages from a plurality of satellites and measuring the location of the GPS receiver corresponding to the received navigation messages, comprising:a wireless hand held means connected to said GPS receiver for receiving or transmitting data and control commands; signal processing means for receiving signals from the satellites, extracting navigation messages from the signals, and measuring the location of the GPS receiver corresponding to the extracted navigation messages and for receiving a control signal from a navigation control base for determining a measuring time in a predetermined time interval; a network means for communication with said base; an input or output means for transmitting to or receiving data from said base through said network means so as to control said GPS receiver; and transmitting means for adding time information corresponding to said navigation messages to compensate the error location of the GPS receiver at which each of the navigation messages was extracted to the relevant navigation message, storing the navigation message and obtaining a difference information of the navigation messages at a measuring time, and transmitting the resultant data to the outside of the GPS receiver through said wireless hand-held terminal; whereby said GPS receiver is operable to power up in response to a message from said base requesting that said receiver transmit data and power down in response to a message from said base acknowledging that said base has successfully received data transmitted from said receiver.