Design And Implementation For The Campus Smart Sound System Based On Network Communication

Broadcast sound system is an indispensable campus infrastructure.With the development of modern information technology and the popularization of multimedia teaching in primary and secondary schools,people have a variety of functional requirements for campus radio systems.The existing radio systems have become increasingly difficult to meet the various needs of school activities.In response to this situation,the thesis designs a campus intelligent audio system based on network communication through the research of network communication technology,embedded technology and digital audio technology,combined with the demand analysis of the system.System by the host computer servers,routers,intelligent speaker equipment,functional expansion of the four components,is a data communications system.The host computer server is the most important communication node of the whole system,It accepts the user's access and transforms the user's operation into the data command to send to the terminal device for execution,receives the feedback information of the terminal device,and displays the real-time status of the device to the user interface,it is the core of humancomputer interaction unction of the system module.The dissertations uses STM32F103VET6 and CK610 processor chip,designed the intelligent speaker equipment and function expansion equipment,and set up the terminal equipment hardware platform.The software design includes the establishment of system communication network,establishment of equipment software platform and implementation of business function software.As follows: 1.Design PC software framework,design humancomputer interaction data center;2.Design terminal software,transplant Nucleus operating system and peripheral driver in CK610 chip,design multi-tasking framework and design system communication protocol;3.Write module drivers,design business function software,complete the main application functions such as real-time playback,online upgrade and time management.Aiming at the problem that the system does not play smoothly and asynchronously when the system performs the online real-time playback function,the software design optimizes the data transmission and decoding performance of the system from the following aspects:1.The data communication program between CPU uses DMA transmission mode to save CPU operation resources while improving the efficiency of communication program,designs communication protocol between CPU to ensure information link reliability.2.Proposes to use the program design method of double thread decoding and D/A conversion multiple buffer alternately according to the actual situation of audio hardware and libmad audio decoder library to solve the problems of noise and playback unfluency.3.The UDP protocol is used to replace TCP protocol as the communication protocol of the network transport layer,it solves the problem of data transmission delay difference when hundreds of speakers are used at the same time,CRC check and data retransmission mechanism are added to make up for the shortcoming of UDP communication protocol's reliability.After a large number of tests in the laboratory environment show that the system can achieve the desired of the design goals.The system has stable operation,fast and reliable data transmission,rich business functions and strong scalability,which can meet various needs of campus activities and has good market and application prospects.