Joint interference alignment and power allocation in MIMO interference network

Interference alignment (IA) technique has shown great promise in many theoretical studies. However, the performance improvement brought by IA in the MIMO interference network has not been investigated well when combined with power allocation. This paper proposed a joint IA-based beamforming design and power allocation method with an objective of optimizing the overall throughput for a MIMO interference network consisting of K transmitter-receiver pairs. Since the joint optimization problem is not convex, we invoke a iterative approach. Based on the minimum interference leakage criterion, the general minimum leakage distributed IA algorithm without the limitation of average power allocation is presented. Then we deal with a network-wide power allocation problem by modified iterative water-filling algorithm, while taking into consideration both the interstream interference and interlink interference. Finally, simulation results show that the proposed method outperforms the minimum leakage distributed IA algorithm in terms of improving throughput and reducing total interference power of the whole MIMO interference network.