Research On Channel Access Technology In Next Generation WLAN

As a representative of short-distance communication,wireless local area network plays an increasingly important role in production and life,providing basic communication support for various services and applications.The ever-increasing communication demands in the industrial field and life scenarios have also put forward higher requirements on the performance indicators of wireless local area networks,promoting the continuous evolution and development of related standards.In order to meet the communication needs of emerging services such as high-definition video and virtual reality,the standardization organization has formulated the next-generation wireless local area network standard with the goal of achieving extremely high throughput.The standard is named EHT.In order to achieve performance improvement,a variety of potential technologies have been considered in the physical layer and medium access control layer of the EHT,and its protocol architecture has also been improved to some extent.Channel access in the wireless local area network is one of the key technologies of the medium access control layer.Its function is to coordinate the channel occupancy of each user node in the network,which affects the performance of the network to a large extent.A new protocol system and architecture has been introduced into the next-generation wireless local area network standard,and the channel access mechanism has also been constrained and expanded adaptively.Following the evolution direction of the next-generation wireless local area network standard,this paper focuses on the channel access technology,and proposes an optimization scheme for the adaptive selection of the primary link and the enhanced utilization of the auxiliary link in the multi-link synchronous access.The specific research contents of the paper are as follows:This paper firstly summarizes the development process of wireless local area network and the key technologies in EHT,and explains the evolution of key technologies in the development process of the standard.Then,it mainly introduces the operation mechanism related to channel access,summarizes the emerging and traditional channel access mechanisms existing in the EHT standard.Focusing on the important protocol improvement of multi-link operation,this paper introduces the advantages,constraints and asynchronous and synchronous operation methods related to channel access.Aiming at the problem that the channel access efficiency is not high due to the single primary link selection mechanism in multi-link synchronous operation,this paper proposes a switching scheme for the primary link selection mechanism in multi-link synchronous access.The index of the channel access density is used as an important reference factor to realize the adaptive switching of the primary link selection mechanism.The protocol flow,frame structure and algorithm involved are optimized and designed,and the effectiveness of the scheme is proved through theoretical analysis and simulation experiments.Aiming at the problem that the access performance of multi-link devices is degraded due to the failure of the auxiliary link to start transmission at the same time as the primary link in the multi-link synchronous operation,this paper proposes a scheme of auxiliary link backoff re-initiation in multi-link synchronous access.Considering the service requirements of the device,the channel access density of the current link,and the remaining time available for the auxiliary link,the back-off is re-initiated and data transmission is performed on the auxiliary link under appropriate conditions.The optimization and design of the protocol process,frame structure and related algorithms involved are carried out,and the effectiveness of the scheme is also proved through theoretical analysis and simulation experiments.