Position estimation

A data processing system for use with a mobile user device that is moveable along a path through a plurality of positions, the data processing system comprising:

• a position estimation module configured so that, for each of the plurality of positions, the position estimation module:
• receives position estimate data and measurement data from a plurality of positioning modules associated with the mobile user device;
• calculates an estimate of the position in dependence on the data received from the plurality of positioning modules;
• and
• stores the estimate of the position and the measurement data, and
• a processing module, configured to:
• process the stored measurement data to calculate at least one revised estimate of a respective position, and to process said at least one revised estimate to update the database of positioning data.

A non-transitory computer readable carrier storing computer program code for use with a data processing system, said data processing system being operable in connection with a mobile user device that is moveable along a path through a plurality of positions, said data processing system including a processor and associated memory, and the computer program code, when stored in said memory and executed by said processor, causing the data processing system to perform a method of:

• at each of the plurality of positions:
• receiving position estimate data and measurement data from a plurality of positioning modules associated with the mobile user device;
• calculating an estimate of the position in dependence on the data received from the plurality of positioning modules;
• and
• storing the estimate of the position and the measurement data;
• subsequently processing the stored measurement data to calculate at least one revised estimate of a respective position;
• and
• processing said at least one revised estimate to update the database of positioning data.

A method of updating a database of positioning data, using a mobile user device moved along a path through a plurality of positions, the method comprising the steps of:

• at each of the plurality of positions:
• receiving positioning data from a plurality of positioning modules associated with the mobile user device;
• and
• calculating an estimate of the position in dependence on the positioning data;
• subsequently processing geographical data, relating to a geographical region in the vicinity of the path, to calculate at least one revised estimate of a respective position;
• and
• processing said at least one revised estimate to update the database of positioning data.