Abstract: Inter-carrier interference (ICI) cancellation in an OFDMA receiving signals from two transmitters is performed by identifying the transmitted sub-carriers that cause the largest ICI to sub-carriers received from other transmitters, and removing the ICI contribution from these sub-carriers. This may be accomplished by calculating the ICI terms only based on the interfering sub-carrier and the frequency offset. Alternatively, the transmissions causing the ICI are demodulated, the ICI on other signals is then determined and subtracted, and other signals are then demodulated. Which transmissions cause the largest ICI on others depends on the relative strength of the corresponding sub-carriers and how much orthogonality is lost. The latter might be due to frequency error, Doppler spread, or a combination of both.

Abstract: 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 accomplished by calculating the ICI terms based on an estimate 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.

Abstract: Inter-carrier interference (ICI) cancellation in an OFDMA receiving signals from two transmitters is performed by identifying the transmitted sub-carriers that cause the largest ICI to sub-carriers received from other transmitters, and removing the ICI contribution from these sub-carriers. This may be accomplished by calculating the ICI terms only based on the interfering sub-carrier and the frequency offset. Alternatively, the transmissions causing the ICI are demodulated, the ICI on other signals is then determined and subtracted, and other signals are then demodulated. Which transmissions cause the largest ICI on others depends on the relative strength of the corresponding sub-carriers and how much orthogonality is lost. The latter might be due to frequency error, Doppler spread, or a combination of both.