Design And Implementaion Of Lte Uu Interface Layer3Protocol Monitor System

The development of new technology in LTE network has raised urgent requirement of new LTE network monitoring system.The air interface has been an important part since the LTE network has used flat network architecture.The Layer3Protocol is in charge of radio resource allocation and the communication between UE and core network.To implement the monitoring of the Uu interface in LTE network,Paper first introduced the business process of LTE Layer3Protocol. The Monitoring system of LTE Uu interface is designed and implemented based on the Uu Interface Tester software platform. The system includes three modules:RRC and NAS protocol decoding module,CDR synthesis of Uu interface and statistical analysis module of the messages and business on Uu interface. After the analysis of the RRC decoding feature using ASN.1,paper gave a method to decode RRC messages using ASN.1decoder. After the analysis of the NAS decoding feature,paper gave a method that can implement the decoding of all information elements, to decode NAS messages..A primary and secondary CDR synthesis program was put forward and designed by which call tracing and business analysis were separated. The data structure module of primary and secondary CDR was instroduced together with a hash dynamic synthesis method to CDR and message synthesis, thus the program can get the network delay and the rate data of certain businesses.In the laboratory under simulation environment,by using simulated eNodeB,the Uu interface monitor grabs the data using simulated USIM and puts the data in cache memory.The Layer3Protocol monitoring module can accomplish the decoding, CDR synthesis and Statistics of CDR and messages.Thus it proves that the program got good results.