Design And Implementation Of RRC In 5G Terminal System

The 5th Generation Mobile Communication(5G)technology has received extensive attention from the industry due to its low latency,high speed,and high reliability.As an important part of the control plane of the 5G New Radio(NR)protocol stack,the radio resource control layer(RRC)can quickly access the cell under the control of the RRC layer to establish a connection with the network.A prerequisite for obtaining normal communication services.The design,development and implementation process of this thesis is based on the major special project of Chongqing Science and Technology Commission "R&D and Application of 5G Terminal Simulation Equipment",combined with the 3rd Generation Partnership Project(3GPP)Release 15 version agreement and domestic and foreign Relevant technical research,analysis,design,implementation,and test verification of the related processes of the RRC sublayer of 5G terminal equipment.The main work and innovations of this thesis are as follows:1.Combining the 3GPP protocol and 5G technical characteristics,the 5G system architecture and air interface protocol stack are studied and analyzed,which focuses on the cell selection in the idle state of the RRC layer and the RRC connection establishment,connection release/suspension and connection in the connected state.Recovery process.A cross-platform data transmission mechanism of personal computer(PC)combined with multi-core digital signal processor(DSP)is used to implement the RRC layer of terminal equipment.2.According to the finite state machine design theory and the functional characteristics of the RRC layer,the existing state of the RRC layer in the protocol is decomposed into several finite states.Use modular design ideas to design RRC layer functions,exception handling procedures,and timers used.Among them,PC multithreading and C language library functions are used to complete the design and implementation of timers;the exceptions are treated according to the results caused by the exceptions.The design of process classification integration can better simplify the processing flow.The RRC layer related function process and other auxiliary modules are developed and realized through the function code,and the function realization process is described in detail.3.For the design and implementation of the RRC layer of the 5G terminal system,the function of the RRC layer is tested by extracting test points and writing test cases.The test plan includes the processing of normal and abnormal processes,and is triggered by the interaction of primitives between layers.The corresponding process of the RRC layer is to observe whether the processing result can meet the protocol requirements.Through 60 rounds of testing,continuous debugging,optimization and improvement based on the implemented functions and the bugs presented by the code during exception handling.The final test results show that the parameter changes in the test samples meet the expected results,and the test case pass rate reaches 100%,which is verified The feasibility and rationality of the RRC layer of the 5G terminal equipment designed in this thesis are verified,and the implemented content meets the protocol consistency requirements.