Design And Implementation Of Expandable BBU Alarm System In LTE Distributed Base Station

In order to meet the market demand of operators and industry users for high reliability,low cost and flexible network configuration of LTE distributed base stations,a communication company decided to start the research and development of scalable BBUs.Compared with the integrated BBU in the traditional distributed macro base station,the expandable BBU separates the functions of the main control transmission unit and the baseband processing unit,and the main control board and the baseband board are respectively inserted in different slots,and support multiple baseband boards.The main control board is mainly responsible for functions such as master control,transmission access,and service data distribution.At the same time,an external clock synchronization source is connected to issue a system synchronization signal to each unit.The baseband board is mainly responsible for the baseband processing function of the wireless interconnection and wireless access,the baseband convergence separation function,and the Ir interface function.The hardware selection of peripheral boards such as baseband boards uses ARM processors with smaller FLASH and SRAM.Therefore,the application layer software cannot reside on each peripheral board,but the operation and maintenance functions of these boards are indispensable.Based on the newly developed expandable BBU and unique hardware selection,this paper refines the requirements of the alarm system in the operation and maintenance software,and analyzes the requirements in detail.Based on the analysis of the requirements of the alarm system,the scheme design and software implementation of the alarm system on the expandable BBU were carried out.The scheme design and software development functions of the alarm system were verified through experiments,and the entire extended BBU alarm system was finally completed.Features.This paper mainly develops from the following parts: first introduces the concept,system architecture and network interface of LTE mobile communication network,then introduces the distributed base station in the important network element eNodeB in the LTE system architecture,and the BBU in the distributed base station.RRU.Secondly,according to the system scheme and overall requirements,the detailed requirements analysis of the alarm system in the expandable BBU is made.In the demandanalysis,the alarm system is divided into functions,and each function is briefly introduced.The hardware structure of the expandable BBU and the limitations of each peripheral board hardware are introduced.Based on the requirements analysis,the functions and interfaces of the extended BBU alarm system are designed and implemented.Finally,on the basis of software and hardware analysis and design,the experimental environment is set up in the laboratory,the function of the alarm system is tested,and the experimental results are analyzed and summarized.The program has been put into use in the project.More than a year,full-featured,stable performance,and recognized by customers.