Abstract: A method, and components for performing such method, is provided for synchronizing multiple user signals in a multi-user communication system. An interference matrix is generated based on time delay and frequency offset information for the active users accessing an OFDMA uplink receiver. User signals are received from the active users and are segmented into blocks, and the interference matrix is applied to each of the blocks. The received user signal is OFDM demodulated and un-used sub-carriers are discarded. Typically, the method includes also applying a factorization matrix formed by factoring a correction matrix created from the interference matrix and an inverse matrix formed based on the factoring results to the user signal blocks, e.g., the correction step includes multiplying each of the blocks from the user signal by each of these three matrices. The corrected user blocks are then concatenated to form a corrected vector signal.