Cooperative positioning

摘要

A system for determining a position of a pair of portable devices in close proximity to one another, the system comprising: a first portable device configured to form first positioning data for use in accordance with a first position determination mechanism; and a second portable device operable to calculate a position in accordance with the first position determination mechanism; wherein the first portable device is configured to transmit said first positioning data to the second portable device, and the second portable device is configured to calculate a position of the first and second portable devices in dependence on the first positioning data.