Patent ID: 7194272
Filing Date: 2007-03-20
Classification: G01S,H04W

Abstract:
1. A calculation method to be used in a radio system comprising a set of transmitters and a set of receivers, in which radio system the time difference between the reception of signals transmitted by the transmitters is measured, and the geometrical time difference of the transmitted signals is calculated, comprising: forming the real time difference between the transmission moments of signals transmitted by a transmitter serving a respective receiver and by the neighbor transmitter of said transmitter as a function of time by means of measuring the time difference between the reception moments of the signals and by means of the geometrical time difference, in such a way that the geometrical time difference is added to the time difference based on the reception moments, summing up directly measured real time differences in order to calculate the real time differences between the other transmitters in the coverage area of the receiver, and calculating the real time differences between transmitters in coverage areas of various receivers by using the time differences that have already been calculated between the transmitters.