Abstract: For the uplink two-cell multiple-input multiple-output cellular interfering network with delayed feedback, a retrospective interference neutralization (RIN) scheme was proposed by using hybrid channel state information at the transmitter (CSIT). First, each user was scheduled to send fresh data streams to each base station so that each base station can obtain side information. Subsequently, each user used the hybrid CSIT to precode information and sent the precoding information to each base station. Finally, each base station eliminated all inter-cell interference by using the precoding information. The achievable degrees of freedom, the achievable sum rate, the simulation validation and the application conditions of RIN scheme were given. Experiment shows that the proposed RIN scheme can provide significant degrees of freedom gain over the time division multiple access and the existing retrospective interference alignment schemes.

Key words: cellular interfering network, channel state information, degrees of freedom, interference neutralization, retrospective interference alignment