Research On The Capacity Of MIMO Wireless Network Based On 802.11ac

In the era of global informationization,information technology is constantly innovating,and more and more intelligent mobile terminal devices are flooding into the network,which making the problem of wireless network capacity more prominent.Therefore,researchers are working on this field to meet people's requirements for network service quality.Traditional wireless communication technology has a drawback—no matter how to adjust the coding strategy,it is difficult to break through the limits of Shannon's capacity.How to improve network capacity becomes a problem.The emergence of Multi-Input and Multi-Output(MIMO)brings new hope to researchers.Although MIMO can improve the network capacity and the network reliability without increasing bandwidth and transmit power,excessive use of Channel State Information(CSI)in actual operation will increases time cost.The MIMO technology in the 802.11 ac protocol can solve this problem by detecting protocol.Therefore,the study of MIMO wireless networks using 802.11 ac protocol has important theoretical and practical significance.In this context,this paper analyzes the capacity of MIMO wireless networks based on the 802.11 ac protocol.The details are as follows:(1)Two distributed APs-STAs(Access Points-Stations)grouping algorithms are proposed under the Signal to Interference and Noise Ratio(SINR)model.In order to find the appropriate APs-STAs grouping in the network,an algorithm based on exhaustive ideas is introduced.The algorithm first sorts the STAs according to the number of antennas,and then determines whether the ordered STAs can satisfy the constraint conditions of the interference processing,and finally selects the groups that satisfy the SINR constraint condition.Compared with the previous algorithm,although the algorithm obtains greater network capacity,it will cause huge time overhead.In order to improve the shortcomings of the algorithm,another time-saving optimization algorithm is given.The experimental results show that both proposed algorithms increase the network capacity by 15%-52%.(2)Two client scheduling strategies are proposed under the condition of ensuring client fairness.Firstly,the 802.11 ac multi-user MIMO passive network is modeled,and the Block Diagonalization(BD)precoding technology is used to eliminate the interference of intra-cell and inter-cell.Secondly,in order to achieve client fairness,this paper defines the client priority according to the rate of data demanding and introduces a greedy strategy.The strategy looks for a scheduling set in odd time slots and performs data transmission,and collects energy in even time slots.Finally,the optimal transmit power is solved by bringing the scheduling set into the convex optimization problem,and the network capacity is further solved.Since the greedystrategy does not obtain the overall optimal solution,so the constraint condition is added to the greedy strategy to give an optimization strategy.That is,the data transmission is guaranteed in the parity time slot.Simulation results show that both strategies can achieve better network performance.