Hybrid interference alignment and power allocation for multi-user interference MIMO channels

This paper proposes a hybrid interference alignment scheme which combines maximizing signal-to-leakage-noise ratio (Max-SLNR) at transmitter and maximizing signal-to-interference-noise ratio (Max-SINR) at receiver. The proposed scheme gives the same sum rate as the existing method using Max-SINR at both transmitter and receiver by avoiding the operation of reversing channel, thus it provides a simpler solution. Furthermore, two power allocation procedures are devised based on game theory and water filling. The gain of these schemes over equal power allocation increases to 2 bit/s/Hz in correlated fading channels as large-scale fading becomes significant. Additionally, user fairness is solved by introducing weighting factors.