Patent ID: 7099378

Claim:
A method for canceling multiple user interference in a communications system wherein a plurality of users communicate over a shared channel, the method comprising: receiving data that provides a plurality of discrete values produced at a sub-symbol interval that is less than a full symbol period; interpolating the signature waveforms for at least some of the plurality of users to a common sampling lattice of the received data; and iteratively calculating a symbol estimate corresponding to a given user at the sub-symbol interval using the interpolated signature waveforms, wherein iterations of calculating the symbol estimate respectively comprise: determining a current interference estimate for a current sub-symbol interval by combining the determined interference contributions for individual ones of the plurality of users corresponding to a previous sub-symbol interval, removing the current interference estimate from the received data to provide an innovation signal for the current sub-symbol interval, and in parallel, adding the innovation signal for the current sub-symbol interval to the interference contribution from a given user to produce an interference cancelled signal for the given user, using the interference cancelled signal for the given user for the current sub-symbol interval to update the symbol estimate for the given user at the current sub-symbol interval, and determining an interference contribution for individual ones of the plurality of users for use in determining a next interference estimate for a next sub-symbol interval.