Abstract: A global positioning system (GPS) receiving system which achieves an equivalent synchronization in time measurement of GPS signals utilizing software without requiring highly accurate synchronization for receiver clocks with time information embedded in the GPS signals. The GPS receiving system performs a relative navigation process after correcting a pseudorange with a time tag error which is attributable to inaccuracy of receiver clocks of first and second moving objects. A relative navigation process correcting an absolute error of a time tag with a clock bias is also described. A differential computation unit calculates a difference between the first pseudorange and the second pseudorange commonized by the time tag commonizing unit. Correction in a time tag error correction unit is performed for the selected GPS data with a common GPS satellite identification number.

Abstract: A GPS receiving system which achieves an equivalent synchronization in time measurement of GPS signals utilizing software without requiring highly accurate synchronization for receiver clocks with time information embedded in the GPS signals. The GPS receiving system performs a relative navigation process after correcting a pseudorange with a time tag error which is attributable to inaccuracy of receiver clocks of first and second moving objects. A relative navigation process correcting an absolute error of a time tag with a clock bias is also described. A differential computation unit calculates a difference between the first pseudorange and the second pseudorange commonized by the time tag commonizing unit. Correction in a time tag error correction unit is performed for the selected GPS data with a common GPS satellite identification number.

Abstract: An artificial satellite navigation system and method. The artificial satellite navigation system includes a global positioning system (GPS) receiver, local satellite, and remote satellite absolute navigation units estimating the position and velocity of a local satellite or a remote satellite and bias and drift of a clock in the receiver. A difference calculation unit calculates differences in position and velocity from the local satellite and remote satellite absolute navigation units. A relative navigation unit estimates the relative position and velocity of the local satellite with respect to the remote satellite. The relative navigation unit navigates the local satellite relative to the remote satellite.