Research On Key Technology Of The Next Generation Wi-Fi MAC Layer

With the rapid popularization of WLAN,the demand for Wi-Fi services and the number of devices are increasing day by day.The current Wi-Fi standard,IEEE 802.11 ax,focuses on improving efficiency and throughput in dense scenarios.It introduces technologies such as OFDMA,high-order modulation and full duplex.It also brings the standardization of 6 GHz high frequency,320 MHz large bandwidth into consideration.However,in many cases,such as home,business and hot spots,the demand for wireless data services will continue to grow beyond the capabilities of the IEEE 802.11 ax.In order to improve peak throughput and reduce latency,the IEEE Protocol Organization established the EHT Interest Group in May 2018 to prepare the next generation of Wi-Fi EHT standards.EHT technologies will include 16 spatial streams,multi-band,multi-AP cooperation,etc.How to integrate the key technologies of the existing MAC layer with the new features of the protocol and make it more suitable for EHT transmission scenarios is an urgent problem to be solved.In this paper,three key technologies in the existing standards are used to optimize the EHT MAC protocol design.A frame aggregation mechanism that separates the MAC frame header from the payload is designed.At the same time,through the frame aggregation mechanism of sending MAC frame header by low MCS on low frequency band and sending payload by high MCS on high-frequency band,the reliability of frame aggregation mechanism is improved by low-frequency low MCS transmission of the MAC headers.In order to overcome the drawback of overhead of bitmap in multi-TID blockack,an efficient multi-TID adaptive strategy is proposed,which is suitable for both single-user and multi-user scenarios,and significantly improve the acknowledge efficiency when a large number of data are to be acknowledged.Aiming at the problem of increasing channel information feedback overhead due to the increase of space streams and bandwidth,this paper designs a channel information feedback mechanism which combines partial RU and differential feedback.It can reduce feedback overhead and feedback delay when feeding back channel information with large bandwidth and multi-space streams,thus ensuring the timeliness of channel information.The design for the key technologies of the IEEE EHT protocol proposed in this paper are all based on the existing standards,and its technical advantages are verified by simulation.The research carried out in this paper is of great significance to promote the formulation of new standards and the development of wireless LAN technology.