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.