Patent ID: 9651667
Date: 2017-05-16
CPC Classifications: G01S

Claim:
1. A method of determining, using a processor, a position of a rover, the method comprising: obtaining rover observations comprising code observations and carrier-phase observations of GNSS signals on at least two carrier frequencies over multiple epochs; receiving correction data comprising for each of the epochs at least one code bias per satellite, the code bias comprising at least one of: (i) a fixed-nature MW bias per satellite or (ii) values from which a fixed-nature MW bias per satellite is derivable, the correction data further comprising at least one of: (iii) an ionospheric delay per satellite for each of multiple regional network stations, (iv) non-ionospheric corrections, or (v) information on the corrections continuity for one or more correction components; applying the correction data to the rover observations using one of (i) creating synthetic reference data for each of the epochs from the correction data for a synthetic station location or (ii) directly correcting the rover observations; determining for each epoch whether an ionospheric cycle slip has occurred in at least one of (i) the rover observations or (ii) observations at the regional network stations used to prepare the correction data; upon determining that an ionospheric cycle slip has occurred, resetting values of state variables affected by the ionospheric cycle slip and retaining values of state variables not affected by the ionospheric cycle slip; and estimating updated values for a set of state variables using each epoch of the rover observations and the correction data, the set of state variables including the state variables affected by the ionospheric cycle slip and the state variables not affected by the ionospheric cycle slip.