Patent ID: 8254281

Claim:
A method for Doppler shift estimation and compensation in a communications system comprising a base station (BS) and a mobile station (MS), the method comprising the steps: (a) transmitting by the BS one or more downlink (DL) signals with one or more pilots signals to the MS; (b) receiving said one or more DL signals by the MS and calculating or measuring a compensation frequency f T ; (c) storing the compensation frequency f T into a memory element; (d) transmitting one or more uplink (UL) signals, with one or more pilots; (e) receiving said one or more UL signals and estimating a Doppler shift f′ D ; (f) transmitting f′ D descriptive data by the BS to the MS; and (g) calculating at the MS an estimation of clock mismatch f′ C using the stored compensation frequency f T and the estimated Doppler shift f′ D according to the formula f′ C =f T −f′ D .