Research On Architecture And Key Technologies Of Multi-radio Multi-Channel Wireless Mesh Access Network

With the continuous development of wireless network technology and the fact that smart cities have become a reality step by step,people are increasingly demanding access to Ethernet resources through wireless networks,and the emergence of a large number of wireless terminal devices for wireless networks used to access Ethernet.Both coverage and throughput have raised higher requirements.IEEE 802.11-based wireless mesh networks have received continuous attention as a self-organizing,easy-to-deploy,highly stable,and capable network with high throughput.However,most of the current IEEE 802.11-based wireless mesh network routers only have one radio.The mesh network uses only one channel for a certain period of time,which results in low network throughput and instability.Configuring multiple radios for nodes in a mesh network and using multiple channels during network running have been proven to effectively improve mesh network performance.However,current research on multi-radio multi-channel(MRMC)mesh networks mainly focuses on channel allocation algorithms or routing algorithms.There are relatively few designs for overall system,especially based on out-of-band control schemes.In this paper,through the demand analysis of multi-radio multi-channel mesh network,the shortcomings of the in-band control scheme and the advantages of the out-of-band control are pointed out.Based on the idea of software-defined network,the out-of-band control MRMC mesh network architecture is designed and implemented.The architecture is divided into a data plane and a control plane.In the data plane,this paper focuses on designing and implementing two key algorithms: radio and channel allocation algorithms and load balancing algorithms.The radio and channel allocation algorithm ensures that the multi-radio multi-channel mesh network can be automatically networked.The load balancing algorithm alleviates the irrational load distribution of the network to some extent,and indirectly improves the performance of the network.In the control plane,this paper divides the node and server side of the control plane into modules,and designs and implements the management system of the MRMC mesh network.This paper tests the access network system in terms of function and performance.The test results show that,on the one hand,the system can not only support the normal operation of the MRMC mesh network,but also has certain compatibility and can work on different hardware platforms;on the other hand,during indoor testing,the MRMC mesh network is compared with the single-channel mesh network of 4 hops.The single hop rate of MRMC mesh network is about 60% higher than that of the single-channel mesh network,but there is still a gap between the theoretical analysis results and the test results.Outdoor test single-hop throughput rate attenuation is less than 15%,and the throughput after fivehop can still reach 318 Mbps.We analyzed the reasons for this gap and gave questions that need to be addressed and what can be improved.