Abstract: The invention relates to methods for providing information for use by a navigation satellite system (NSS) receiver and/or processing entity receiving data therefrom, for positioning purposes. In one embodiment, satellite orbit information and satellite clock error information applicable over a wide area and to epoch t1 is obtained (s10) for each of a plurality of NSS satellites. Ambiguities in the carrier phase of NSS signals received at epoch t1 at narrow area reference stations are estimated (s20). For each satellite, the satellite orbit and satellite clock error at epoch t2 are predicted (s30). A residual error for modelling errors having a common or substantially common line-of-sight dependency is estimated (s40a). The residual error is added (s50a) to the predicted satellite clock error to form a redefined satellite clock error. The invention also relates to variants of the above-mentioned method, and to systems, computer programs, and computer program products.

Abstract: The invention relates to a method carried out by a navigation satellite system (NSS) receiver or a processing entity receiving data therefrom, for estimating parameters useful to determine a position. The NSS receiver observes NSS signals from NSS satellites over multiple epochs. A filter, called “precise estimator”, is operated, which uses state variables, makes use of NSS signals observed by the NSS receiver, and computes its state variable values based on observations that are not derived from NSS signals observed by the NSS receiver. Seeding information is obtained, and a constrained solution, called “seeding- and ambiguity-constrained solution”, is computed by constraining the ambiguities of the precise estimator by the seeding information, by resolving the resulting ambiguities, and by constraining at least one of the other state variables of the precise estimator by the resolved ambiguities. A corresponding system is also disclosed.

Abstract: The invention relates to a method carried out by a navigation satellite system (NSS) receiver or a processing entity receiving data therefrom, for estimating parameters useful to determine a position. The NSS receiver observes NSS signals from NSS satellites over multiple epochs. A filter, called “precise estimator”, is operated, which uses state variables, makes use of NSS signals observed by the NSS receiver, and computes its state variable values based on observations that are not derived from NSS signals observed by the NSS receiver. Seeding information is obtained, and a constrained solution, called “seeding- and ambiguity-constrained solution”, is computed by constraining the ambiguities of the precise estimator by the seeding information, by resolving the resulting ambiguities, and by constraining at least one of the other state variables of the precise estimator by the resolved ambiguities. A corresponding system is also disclosed.