Greedy Algorithm for Stream Selection in a MIMO Interference Channel

In this paper, a Greedy stream selection algorithm is proposed for a M × N K -user Multiple Input Multiple Output Interference Channel (MIMO-IC). The proposed algorithm tries to find the “best stream” allocation by removing streams with low signal-to-interference-plus-noise ratio (SINR) until the system capacity cannot be increased. The algorithm runs with the Min- imum Mean Square Error Interference Alignment (MMSE-IA) algorithm and its performance is compared with the exhaustive search by Monte Carlo simulations in two different scenarios. The first scenario is refereed as symmetric attenuation scenario which no path loss is considered among the network nodes. In the second one, by its time, the signal strength is function of the distance, thus more streams are allowed to be transmitted. The results show that the Greedy algorithm outperforms, in both scenarios, any fixed solution and it achieves a good Sum Capacity performance when compared with the best stream allocation (exhaustive search), but with less computational complexity.