Abstract: A method for calculating a position of a mobile device relative to a selected reference station of a plurality of reference stations, the method comprising: receiving satellite signal measurements associated with a first reference station; receiving location signals from a plurality of satellites; tracking a baseline between the mobile device and the first reference station using the satellite signal measurements associated with the first reference station and the location signals to provide the position of the mobile device relative to the first reference station; sending a handover request, the handover request comprising the current position of the mobile device; receiving a handover message comprising integer ambiguities for a baseline between the first reference station and the second reference station; initialising tracking of a baseline between the mobile device and the second reference station using the integer ambiguities of the handover message; receiving satellite signal measurements associated wit

Abstract: A robotic lawnmower (100) for movable operation within a work area (205) has a satellite navigation device (190), a deduced reckoning navigation sensor (195) and a controller (110). The controller causes the robotic lawnmower (100) to movably operate within the work area (205) in a first operating mode, the first operating mode being based on positions determined from satellite signals received by the satellite navigation device (190). The controller determines that a position cannot be reliably determined based on satellite signals received by the satellite navigation device (190), and in response thereto causes the robotic lawnmower (100) to movably operate within the work area (205) in a second operating mode. In the second operating mode, a deduced reckoning position estimate is obtained by the deduced reckoning navigation device (195). A search space is defined using the deduced reckoning position estimate, and the satellite navigation device (190) is recalibrated based on the defined search space.

Abstract: A robotic lawnmower (100) for movable operation within a work area (205) has a satellite navigation device (190), a deduced reckoning navigation sensor (195) and a controller (110). The controller causes the robotic lawnmower (100) to movably operate within the work area (205) in a first operating mode, the first operating mode being based on positions determined from satellite signals received by the satellite navigation device (190). The controller determines that a position cannot be reliably determined based on satellite signals received by the satellite navigation device (190), and in response thereto causes the robotic lawnmower (100) to movably operate within the work area (205) in a second operating mode. In the second operating mode, a deduced reckoning position estimate is obtained by the deduced reckoning navigation device (195). A search space is defined using the deduced reckoning position estimate, and the satellite navigation device (190) is recalibrated based on the defined search space.