APPARATUS AND METHODS FOR ESTIMATING AND CORRECTING FREQUENCY OFFSET IN LTE

摘要

The invention provides an apparatus and methods for estimating and correcting frequency offset based on Zadoff-Chu sequences that are used in LTE (Long Term Evolution) as either random access preambles or dedicated pilots. By measuring the power difference of the first two largest peaks among the correlation output between the received signal and the concerned Zadoff-Chu sequence with different cyclic shifts, the apparatus estimates the frequency offset between the transmitter and receiver using the relationship between the frequency offset and the power difference of the first two largest peaks. The correcting is performed based on the estimated frequency offset. The apparatus and the method disclosed can estimate higher frequency offset, and can tolerate more noise.