Research On Scheduling Algorithm And Implementation On MAC Layer Protocol In TDMA Wireless Mesh Network

As a new network architecture in wireless network,Wireless Mesh Network(WMN)based on the IEEE 802.16 standard has attracted many attentions from companies and schools.Compared with the traditional wireless network,it has the advantages of flexible networking,a high transmission rate,and a wide coverage area.How to maximize the use of limited resources and ensure the user business Qo S in WMN is an important research area,which has got attentions from many researchers.Wireless mesh network based on TDMA has the characteristics of large system capacity,good communication quality,and high resource utilization.The resource scheduling mechanism in MAC layer of WMN is responsible for user bandwidth allocation and data scheduling,so the design of a reasonable MAC layer protocol and scheduling mechanism has a great impact on the wireless resource utilazation and user Qo S.This work is focused on the designing and implementing of the sea-level wireless communication project in laboratory.Due to the WMN based on the IEEE 802.16 standard can not meet the time delay requirement and the existing scheduling algorithm in MAC layer can not meet the needs of sending massive businesses,we designed and improved the system based on IEEE 802.16 standard wireless mesh network to meet the project's sea-level wireless communication scenario,and then completed the system.Firstly,the composition of the MAC layer protocol based on the IEEE 802.16 standard,the hierarchical functions and the frame structure are analyzed in detail.Secondly,the standard frame structure is improved in the time domain,which could reduce the signaling overhead and increases the utilization rate of resources,to meet the goal of the requirements of massive business es transmission and guarantee use r Qo S in a relatively stable communication environment.Then it designs an accessing network mechanism and proposes a resource allocation algorithm based on the coloring theory.According to the business priority,they are grouped when scheduling.And the strategy of three rounds scheduling is adopted in group to meet the requirements of different service Qo S.A threshold is set for the number of processing real-time business between the groups to prevent other business starving to death.The scheme based on the MAC layer protocol of the TDMA wireless mesh network is designed and implemented based on FPGA in this thesis.According to the different functions,the MAC layer protocol is divided into eleven sub-modules,which are the main program module,the convergence sublayer interface module,the classifier module,the data processing module,the connection management module,the resource scheduling module,the network synchronization module,maintenance module,routing management module,public data module,and PHY interface module,then the function of each of sub-module is analyzed.Finally,the designing and implementation of the scheduling module and the relationship with other interface modules are introduced.As the scheduling module holds a critical position in the entire Mesh network,the design of the scheduling module greatly affect the performance of the network.Furthermore,it can not only ensure the business Qo S requirements,but also improve the efficiency of the entire network data transmission.In this thesis,a test bed is built to verify the functions of the wireless mesh network,such as accessing network,synchronization and resource scheduling.