A method and a receiver for receiving positioning signals are disclosed. The positioning signals are received from a plurality of first sources in a first frequency range and from a plurality of second sources in a second frequency range different from the first frequency range. The receiver is switched between the first and second frequency ranges to receive the positioning signals, and the receiver obtains time offset information about a time taken to switch the receiver between the first and second frequency ranges, by obtaining a solution to a set of simultaneous equations based on combined navigation data for the first and second sources.