Patent ID: 6577615
Filing Date: 2003-06-10
Classification: H04W

Abstract:
A method for frequency synchronization of a mobile station of a radio communications system, the method comprising the steps of:providing frequency channels in the radio communications system which are formed both by time slots and by broadband frequency ranges wherein information from one or more connections is transmitted simultaneously in the frequency channels between mobile stations and base stations, and wherein the information from different connections is distinguishable by spreading codes; providing one of the frequency channels for repeated frequency synchronization of the mobile stations in a downward direction; transmitting a chip sequence within one frequency channel; determining estimated values for the chip sequence from received signals by the mobile station to be synchronized; calculating a phase drift in the estimated values from at least a comparison of the estimated values with a reference chip sequence, which is identical to the transmitted chip sequence; determining a frequency offset from the phase drift; and using the frequency offset by the mobile station for frequency synchronization.