Design And Implementation Of NAS Protocol Stack On TD-LTE Broadband Multimedia Trunking System

Trunking communication technology and TD-LTE technology combine to form a TD-LTE broadband wireless multimedia trunking system.The main advantages of TD-LTE include: faster communication transmission speeds,wider network spectrum,and more flexible communication methods.This article analyzes the core functions of the non-access layer of the TD-LTE broadband wireless multimedia trunking system and its main protocol flow.The non-access stratum signaling does not need to be processed by the access layer radio access controller and base station,and only the terminal side and the network side need to participate.The non-access stratum protocol is a group of protocol sets.The set of protocols includes protocols for the management of mobility and session management between the terminal side and the network side.The EPS mobility management protocol defines a terminal mobility management process.The EPS session management protocol defines the management and control process of the EPS bearer context,and cooperates with the bearer control function provided by the access layer to complete the user plane control process.This article first introduces the current status of TD-LTE technology development and the related background of trunking communication system.It also describes the author's main work combined with the functional block diagram of non-access layer implementation,and introduces the overall structure of this paper.Then based on the background analysis,the TD-LTE broadband multimedia trunking system architecture is introduced,and the structure of the TD-LTE control plane protocol stack is analyzed in detail,and the related protocol layers are introduced.At the same time,it gives the research and analysis of related literatures and papers on the realization of existing non-access layer functions,and points out the design scheme and implementation ideas for this paper.The third and fourth chapters of this article are the main chapters.Based on the TD-LTE broadband wireless multimedia trunking system,the functional function of the terminal non-access layer is designed and implemented.The third chapter describes the overall architecture design of the non-access stratum,functional design of the four main functional components of the non-access stratum at the terminal side,including thread initialization,location information management functions,non-access layer signaling Connection management capabilities,message construction,and resolution capabilities.The fourth chapter carries out the realization of function function on the basis of the designing scheme of the third chapter,and expounds the corresponding implementation process description of the design scheme.The fifth chapter is the test part of this paper.It mainly tests the function implementation of the non-access stratum protocol,including the design of test steps and test cases.Unit tests are performed for each functional module according to the test procedure to ensure the feasibility of the design.And correctness.Finally,the sixth chapter summarizes the full text.After completing the functions designed in this paper,it points out the unimplemented functions and points out the next working direction.