The Research On Interference Cancellation In Wireless Networks

The fifth generation telecommunication will gradually be applied to various fields for the characteristics of large bandwidth,low latency and high reliability.The complex and diverse application scenarios and dense network deployment make the system performance greatly be affected by inter-cell interference and inter-user interference.How to effectively manage interference has become an important research direction of current wireless communica t io n technology.As a key technology of interference management,interference alignment can effectively cancell interference and improve network performance.For multi-cell mult iinput multi-output(MIMO)interference multiple access channel(IMAC)networks,this paper proposes a joint base station association interference alignment and cancel at io n method.The traditional joint interference alignment and cancel ation methods only focus on the situation that the association amongst users and base stations is predetermined,but ignore the influence of the association amongst users and base stations on the system performance.As an important technology of coordinated multipoint transmission and reception,dynamic access point selection can effectively improve the performance of the system.Due to base station association is a kind of dynamic access point selection,the dynamic base station association can be used to improve the degrees of freedom.For the situation that the association amongst users and base stations can be dynamica l ly selected,a joint base station association interference alignment and cancel ation method is proposed in this paper.In order to solve this problem,taking the maximum degrees of freedom that the system can achieve as the goal to establish the objective function,and then it is transformed into a quadratic constrained integer programming model.Moreover,the model is decomposed into a series of quadratic constrained integer programming models,and each model is transformed into a mixed integer linear programming model.By solving the mixed integer linear programming model,the solution of the objective function is obtained.According to the solution,the joint base station association interference alignme nt and cancellation scheme is determined,and the maximum degrees of freedom that the system can achieve is obtained.Finally,the joint base station association interference alignment and cancel ation method is simulated.The results show that,this method can effectively improve the degrees of freedom,compared with the joint interference alignment and cancel ation for the situation that the relationship is predetermined.