Finite Feedback Interference Alignment Algorithm Based on Upper Triangular Decomposition

In the receiving system with multi-cell edge users, the traditional limited feedback precoding method has quantization error and the system performance is not ideal. Therefore, a limited feedback precoding algorithm based on upper triangular decomposition is proposed. First, Adjust the system channel matrix by considering the channel quality of the cell user; Secondly, The joint channel is triangulated to obtain an equivalent model, and all users' data streams are integrated for water injection method power allocation; Finally, the precoding matrix and the interference suppression matrix are designed by minimizing the interference leakage and the minimum mean square error criterion. The simulation results show that the proposed algorithm can reduce the quantization error and improve the performance of the system.