Patent ID: 8694250

Claim:
A method of operating an apparatus comprising a processor and a storage element with instructions that enable the processor to process data collected by at least two receivers from multiple satellites of multiple Global Navigation Satellite Systems (GNSS) where at least one GNSS is Frequency Division Multiple Access (FDMA), comprising: a. obtaining data sets comprising a first data set from a first receiver and a second data set from a second receiver, wherein the first data set comprises a first FDMA data set and the second data set comprises a second FDMA data set, wherein at least one of a code bias and a phase bias may exist between the first FDMA data set and the second FDMA data set, b. determining at least one receiver-type bias to be applied when the data sets are obtained from receivers of different types, c. processing the data sets, based on the at least one receiver-type bias, to estimate sets of carrier floating-point ambiguities, and d. determining carrier integer ambiguities from the carrier floating-point ambiguities, comprising determining at least two integer ambiguity candidate sets with at least one confidence indicator for each of a first candidate set and a second candidate set, and at least one of (i) comparing at least one confidence indicator for the first candidate set with at least one confidence indicator for the second candidate set to determine whether to apply a receiver-type bias; (ii) applying no receiver-type bias if the comparison shows a first confidence indicator to be conclusively better than a second confidence indicator, applying the at least one receiver-type bias if the comparison shows the second confidence indicator to be conclusively better than the first confidence indicator; (iii) applying no receiver-type bias if the comparison shows a first confidence indicator to differ from a second confidence indicator by less than a predetermined amount; and (iv) applying no receiver-type bias if said at least one receiver-type bias is below a predetermined threshold.