CPC G01S 19/47 (2013.01) [G01S 19/45 (2013.01); G01S 19/54 (2013.01); G01C 21/165 (2013.01); G01C 21/20 (2013.01); G01S 19/40 (2013.01); G01S 19/41 (2013.01); G01S 19/53 (2013.01)] | 20 Claims |
1. A method for estimating attitude and heading of a system, comprising:
obtaining inertial measurements from one or more inertial sensors;
obtaining raw carrier phase measurements from two or more Global Navigation Satellite System (GNSS) receivers communicatively coupled to respective GNSS antennas;
determining carrier phase double difference (CDD) measurements from the raw carrier phase measurements;
determining predicted CDD values based on statistical filter predicted states;
determining CDD measurement residuals and respective variances based on the CDD measurements and the predicted CDD values;
applying a wrapping function with limit of ±half of a GNSS carrier signal wavelength to the CDD measurement residuals to generate refined CDD measurement residuals;
validating the refined CDD measurement residuals to determine valid CDD measurements; and
estimating attitude and heading of the system using the valid CDD measurements and the inertial measurements.
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