Patent ID: 6292750
Filing Date: 2001-09-18
Classification: G01C,G01S

Abstract:
An improved vehicle positioning system, comprising:a global positioning system (GPS) processor for providing GPS measurements including pseudorange, carrier phase, and Doppler shift;an inertial measurement unit (IMU) for providing inertial measurements including body angular rates and specific forces;a central navigation processor, which are connected with said GPS processor and said IMU, comprising an inertial navigation system (INS) processor, a robust Kalman filter, and a carrier phase integer ambiguity resolution module; andan input/output (I/O) interface connected to said central navigation processor;wherein said GPS measurements are passed to said central navigation processor and said inertial measurements are injected into said inertial navigation system (INS) processor;an output of said INS processor and said GPS measurements are blended in said robust Kalman filter; an output of said robust Kalman filter is fed back to said INS processor to correct an INS navigation solution outputting from said central navigation processor to said I/O interface;said INS processor provides velocity and acceleration data injecting into a micro-processor of said GPS processor to aid code and carrier phase tracking of GPS satellite signals;an output of said micro-processor of said GPS processor, an output of said INS processor and an output of said robust Kalman filter are injected into said carrier phase integer ambiguity resolution module to fix global positioning system satellite signal carrier phase integer ambiguity number;said carrier phase integer ambiguity resolution module outputs carrier phase integer number into said robust Kalman filter to further improve positioning accuracy; andsaid INS processor outputs navigation data to said I/O interface.