Patent ID: 7702460

Claim:
An apparatus, comprising: a first navigation unit provided in a first moving vehicle that comprises a hybrid global positioning system (GPS)/inertial navigation system (INS) component, wherein the hybrid GPS/INS component provides first GPS information and first INS information for the first navigation unit; wherein the first navigation unit is configured to receive second GPS information and second INS information from a second navigation unit provided in a second moving vehicle; wherein the second navigation unit comprises a GPS component configured to determine a double-differenced GPS carrier phase measurement through employment of the first GPS information and the second GPS information; wherein the first navigation unit comprises a relative Kalman filter configured to update an INS error estimate for an estimate of a relative position between the first and second navigation units based on a combination of the double-differenced GPS carrier phase measurement and the first and second INS information, wherein each GPS/INS hybrid positioning solution incorporates OPS update measurements to calculate the INS error estimate; wherein the relative Kalman filter is configured to feed back Kalman corrections to update an INS error estimate for the relative position estimate; wherein the relative Kalman filter is configured to feed back covariances to the GPS component for at least one of detection of cycle slips and recovery of an integer solution.