Abstract: A method of determining the location of a mobile receiver is provided. The method works within a radio system in one or more dimensions, the radio system includes a network of transmitters the positions of which are known. The method comprises the steps of: compiling a list of the signals detected by the receiver, sending said list to a calculation device; constructing a position function which relates to the probability that the receiver is at a given location, which position function has components corresponding to each member of the list, each component including a predetermined probability function that depends on mobile receiver position; and evaluating said position function to determine a position that corresponds to the highest probability of location, and defining that position to be the location of the mobile receiver.

Abstract: In a terminal 106 having a receiver 202 for receiving the signals from plural transmission sources 101-105 whose positions and transmission time offsets are unknown within the terminal, a method is provided for determining the change in the time (elapsed time) at the terminal between two instants. At a first position of the terminal a first set of measurements, aligned to a first instant, of a signal parameter representative of the time or phase of receipt of said signals from said plural transmission sources relative to one or more of them, or to a reference, or to a terminal clock is obtained. Then at a second position of the terminal a corresponding second set of measurements, aligned to a second instant, of a signal parameter representative of the time or phase of receipt of said signals from said plural transmission sources relative to one or more of them, or to the reference, or to the terminal clock is also obtained.

Abstract: In a terminal 106 having a receiver 202 for receiving the signals from plural transmission sources 101-105 whose positions and transmission time offsets are unknown within the terminal, a method is provided for determining the change in the time (elapsed time) at the terminal between two instants. At a first position of the terminal a first set of measurements, aligned to a first instant, of a signal parameter representative of the time or phase of receipt of said signals from said plural transmission sources relative to one or more of them, or to a reference, or to a terminal clock is obtained. Then at a second position of the terminal a corresponding second set of measurements, aligned to a second instant, of a signal parameter representative of the time or phase of receipt of said signals from said plural transmission sources relative to one or more of them, or to the reference, or to the terminal clock is also obtained.