Combined per-user SLNR and SINR criterions for interference alignment in uplink coordinated multi-point joint reception

An interference alignment (IA) algorithm for uplink coordinated multi-point (CoMP) is proposed. For the design of precoder at the transmitter, the unselfish per-user signal-to-leakage-and-noise ratio (SLNR) criterion is used. On the other hand, the per-user signal-to-interference-and-noise-ratio (SINR) criterion is adopted to determine the decoder of the receiver. The proposed algorithm does not rely on the channel reciprocity and thus is suitable to operate in case of different user transmission powers. Through iterative procedure, we show that the per-user-based criterion which keeps user data streams orthogonal can suppress interference effectively and achieve higher sum rate than the conventional IA algorithms, such as minimum leakage and maximum per-stream SINR algorithms in the multi-user CoMP joint reception scenarios.