Research On Enhanced-Multicast Technology In Next Generation Wireless Lan

Multicast technology is a point-to-multipoint data transmission strategy between a sender and all the receivers in the multicast group.Because of its advantages of saving spectrum resource and reducing network load,the applications of multicast in wireless local area network(WLAN)are increasingly widespread and have attracted more and more attention.The next generation of WLAN 802.11 ax protocol is an important technical direction of 5G for indoor and outdoor dense network deployment environments,which is designed to enhance the network spectrum efficiency,throughput and performance in dense network environments.802.11 ax is a current research hotspot in wireless communication fields.Combining multicast technology and the next generation of WLAN will benefit the improvement of network performance greatly.However,the existing WLAN multicast technologies use a single multicast group for multicast traffic transmission.In a large-scale intensive user networking environment,multicast users have different link rates due to different channel conditions.The performance of multicast users that have high link rates is bound to be limited by multicast users with low link rates in the same multicast group,and the user satisfaction of multicast users that have high link rates is also pulled low,and which is unfair to them,and at the end,resulting in the overall performance of the multicast group can’t be optimal.If a multicast group is subdivided,the multicast users with large link rate differences are divided into different submulticast groups,which can reduce the influence of multicast users with low link rates on multicast users with high link rates,and the overall performance of the multicast group can be improved.Based on the above problems,the main works of this paper include the following aspects:Firstly,this paper establishes the mathematical models of two multicast scenarios to analyze the performance optimization of WLAN multicast technology.To improve the efficiency,a heuristic multicast user grouping algorithm is proposed,which can effectively reduce the time complexity.Secondly,based on the analysis results from multicast mathematical models,combined with the uplink and downlink OFDMA technology in 802.11 ax protocol,an enhanced-multicast technology for the next generation of WLAN in the large-scale dense network environments is proposed in this paper.At the same time,the MAC frame is innovated,and some new control frame types are proposed in this paper.The simulation results show that the enhanced-multicast technology proposed in this paper performs better in throughput,frame cost,delay and packet delivery ratio than other multicast technologies,which can significantly improve the performance of multicast in the large-scale dense network environments.Thirdly,with the theoretical analysis,the hardware and software platform and the architectures of AP and multicast-users are designed.The platform is composed of several FPGA development boards and host computers.The FPGA development boards are used to implement the functions of AP and multicast-users respectively.The implementation framework is divided into two parts: the software module and the hardware module.The host computer connected with the AP is used as a multicast data source,while the host computer connected to the multicast-user is used for packet analysis of the received multicast data.The experimental results of the platform show that the enhanced-multicast technology is feasible.