Research Of Interference Problems In OBSS Scene

Today,high-speed wireless access technology is changing with each passing day,as the product of the combination with computer network and the mobile communication technology,WLAN technology has made rapid development.Subsequently,the OBSS(overlapping basic service set)’s interference under WLAN’s high-density deployment has been a problem to be considered.Therefore,this paper focuses on how to improve the channel capacity in OBSS and how to solve the interference problem with less cost.One hand,this paper use the idea of partial interference alignment,research the OBSS’s special scene that the strong and weak interference coexist,while mainly to strong interference.When only using the distributed interference alignment for the strong interference region,since distributed interference alignment can only align the interference of strong interference region,without the interference of the weak treated.Hence,weak interference can limit the system’s channel capacity.For this problem,the paper takes weak interference’s influence factor,and add weak interference’s influence to the covariance matrix of distributed interference alignment to eliminate the weak interference while eliminating the strong interference in the iteration.Simulation results show that the algorithm can effectively improve the channel capacity of the system,and greater power attenuation factor,the improved effect is more obvious.On the other hand,For OBSS scenario,this paper researches the optimal transmit antenna selection based on the poor search’s distributed interference alignment and a low complexity transmit antenna selection algorithm based on greedy strategy.On this basis,it gets a new distributed interference alignment scheme under the condition of transmitting antenna selection.The scheme is completed by two steps.First,for each BSS(basic service set),using the antenna selection algorithm based on the maximum Frobenius norm to find transmission antennas with relatively good channel quality from the channel matrix.Then,on this basis,using distributed iterative interference alignment technology to align interference.Compared with the optimal emission antenna selection and low complexity algorithm based on greedy strategy,The scheme only loss a few dB in the performance,but can exponentially reduce algorithm complexity,thus effectively improve the transmission capacity in the effective time of a block MIMO channel.At last,On the basis of research about distributed interference alignment technology under the condition of transmitting antenna selection,this paper further studies distributed interference alignment algorithm under the condition of joint antenna selection between sending side and receiving side.The research results have a certain reference value on the solution of interference problem in OBSS scene.