Reporting of changes in navigation map data for navigation system

A navigation unit arranged to communicate with a cellular communication network, the navigation unit comprising:

• a processor connected to a navigation device, a mobile communication unit and toa memory unit,
• the navigation device being arranged to detect an actual location of the navigation unit,
• the memory unit being arranged to store navigation map data, and
• the processor being arranged to:
• calculate a route to a destination using the navigation map data;
• detect when the calculated route to the destination is left, and if so, store detected position data in the memory unit;
• filter out detected position data corresponding to detours for fuel stations, restaurant visits, and other events associated with prolonged periods of the navigation unit being stationary;
• and
• initialize a transmission of the detected and filtered position data to a navigation map server via the mobile communication unit upon detection that:
• a detected actual location is back on the calculated route,
• the detected actual location is on a recalculated route to the destination from the actual location, or
• the destination has been reached.

A method performed by a navigation unit of a vehicle for updating navigation map data, comprising:

• detecting an actual position;
• calculating a route for a vehicle to a destination using navigation map data;
• detecting when the calculated route to the destination is left, and if so, continuously storing detected actual position data until:
• the vehicle is back on the calculated route,
• the vehicle is on a recalculated route to the destination from the actual position, or
• the destination has been reached;
• wherein storing detected actual position data comprises filtering out detected position data corresponding to detours for fuel stations, restaurant visits, and other events associated with prolonged periods of the navigation unit being stationary;
• and then
• transmitting the detected actual position data to a navigation map server.

A navigation map server in communication with a network node associated with a group of cells of a cellular communication network, the navigation map server comprising:

• a memory unit for storing navigation map data,
• a map update service module being arranged to receive position data from a plurality of navigation units via the cellular communication network, the position data comprising deviations from a calculated route, wherein data corresponding to detours for fuel stations, restaurant visits, and other events associated with prolonged periods of the navigation unit being stationary are filtered out;
• and
• an evaluation module in communication with the map update service module, the evaluation module being arranged to evaluate the position data to obtain navigation map update data for a geographically limited area associated with the group of cells based on a threshold value of occurrences of the position data.

A method for updating navigation map data, comprising:

• receiving via a network node associated with a group of cells of a cellular communication network position data from a plurality of navigation units,
• storing the position data comprising deviations from a calculated route, filtering out detected position data corresponding to detours for fuel stations, restaurant visits, and other events associated with prolonged periods of the navigation unit being stationary;
• and
• evaluating the position data to obtain navigation map update data for a geographically limited area associated with the group of cells, wherein evaluating the position data to obtain navigation map update data is based on a threshold value of deviations from the calculated route.