Combined channel estimation and frequency correction for packet oriented mobile communication systems

We show how the well known least square (LS) algorithm can be used for combined channel estimation and frequency correction in packet oriented mobile communication systems. The method is derived by investigation of the effect of a frequency offset, e.g., due to the instability of the local oscillators, on the LS estimates. The algorithm corrects frequency offsets resulting in phase shifts per symbol that are in the range of several degrees. Imperfect correlation properties of the applied synchronisation sequence are automatically compensated by the algorithm