INTER-CARRIER INTERFERENCE CANCELLATION FOR OFDMA SYSTEMS

摘要

Inter-carrier interference (ICI) cancellation is performed on a received signal comprising signals transmitted by a transmitter to a plurality of users. ICI cancellation is performed for a given user by identifying the signals transmitted to other users that cause the largest ICI to signals transmitted to the receiving user, and selectively removing the ICI contribution from these transmissions. This may be acc omplished by calculating the ICI terms based on an es timate of the transmitted signal calculated as the received signal divided by an estimate of the channel. Alternatively, the transmissions causing the ICI may be selectively demodulated and decoded, and the improved estimates of the transmitted signal used for ICI estimation and cancellation. Which transmissions cause the largest ICI on others depends on the relative strength of the corresponding data and pilot symbols and how much orthogonality is lost.