Research on interference alignment algorithm based on user grouping

In a multi-cell and multi-user cellular system, the communication quality of users is seriously affected due to the existence of inter-cell interference (ICI) and inter-user interference (IUI).As an interference management technology, interference alignment (IA) can not only eliminate interference, but also greatly improve the degree of freedom of the system, that is, improve the system capacity.This paper proposes a three-cell multi-user grouping interference alignment algorithm,which first groups the users of the three cells,converts the complex interference channel into a simple communication channel,and then eliminates the inter-user interference by transmitting beamforming matrix, and eliminates inter-cell interference by designing the receiving beamforming matrix.When calculating the transmitting beamforming matrix, the multi-matrix connected at the transmitter and solved by the eigenvector.When calculating the receiving beamforming matrix, the receiving beamforming matrix is obtained by using the inverse property of the matrix.Compared with the traditional method of solving the transmitting beamforming matrix and the receiving beamforming matrix, the complexity of the algorithm is greatly reduced.And the simulation shows that the algorithm has a better sum rate than the traditional interference alignment algorithm under the same signal-to-noise ratio (SNR).