Abstract: A method and apparatus for multi-user detection is disclosed. A signal is received in a shared spectrum, and samples of the received signals are produced as a received vector. The received vector is segmented into vector segments. Each segment has a portion that overlaps with another segment and the overlapping portion includes at least one chip less than twice a channel impulse response length. For each vector segment, symbols are successively determined for communications by determining symbols for a communication in the communications, ordering the communications by received power and removing a contribution of the communication from the vector segment. The determining of symbols includes equalizing an input vector corresponding to a segment of the received vector using fast Fourier transform. The determined symbols are assembled into a data vector for each communication in the communications.