基于ZigBee的无线嵌入式系统的研究与开发

发布时间：2018-01-16 22:29

本文关键词：基于ZigBee的无线嵌入式系统的研究与开发　出处：《江南大学》2012年硕士论文　论文类型：学位论文

【摘要】：随着物联网技术的发展,工业生产的信息化程度越来越高,管理者对生产状况需要随时都能掌握,要求生产装置的信息化程度更高。目前工业生产的通信网络布线主要通过RS232、CAN、以太网等传统有线方式,虽然能够满足一定的要求,但是由于生产设备的升级越来越迅速,随之带来的成本越来越高,将无线设备引入工业领域代替有线通信方式,在降低系统升级成本和使系统升级更加灵活方面具有一定的意义。目前,无线传感网络技术发展比较成熟,已经成功应用于智能交通、智能医疗以及环境监测等行业,国内对于无线传感网络以及物联网相关技术的研究近几年才在国家政策的支持下发展相对迅猛。本文采用美国德州仪器(TI)公司的CC2530芯片作为主控芯片,并结合ZigBee无线技术、低功耗设计、时间同步技术、串口通信技术等,以嵌入式软硬件协同设计思想设计并实现了一套基于ZigBee通信技术的嵌入式无线通信模块,将该模块嵌入到现有工业系统中广泛使用的控制监控设备PLC、HMI中,整合工业PC组成无线工业通信网络,实现物联网技术在工业行业的应用和推广。系统的硬件电路以CC2530芯片为核心,采用嵌入式模块化设计,设计了两类设备,分别用于监控通信和低功耗路由通信。利用RTC模块和模拟开关控制CC2530的电源,来克服ZigBee路由设备无法进入休眠的弊端,以达到降低系统整体功耗的目的。模块对外提供常用的RS232和RS485的通信接口,可以与其余工业现场设备进行连接通信。模块的下位机软件在TI的Z-Stack协议栈的基础上完成,采用多任务并行处理机制,包括协议数据转换、时间同步协议服务、无线通信、串口通信等任务,各任务之间通过设置事件标志进行同步。利用MODBUS站号和ZigBee网络地址绑定,形成地址映射表完成两个协议数据的转换,完成MODBUS网络和ZigBee无线网络的数据交互和网关功能。采用PTP精确时间同步协议完成网络节点的时间同步,在MAC层添加PTP服务的响应,并触发读取硬件时间戳信息,提高系统节点的时间同步精度。经测试表明,本文设计的模块硬件部分的发射功率达+2dBm,接收灵敏度达-98dBm,通信链路预算达100dBm,实际可靠通信距离可达100m,通过PA扩展可达1000m。低功耗模块在休眠状态实际工作电流仅为RTC芯片BL5372的400nA,模块通信速率达219kbs,通信误包率在0.1%左右,时间同步精度达+50us,且波动较小。本文设计的基于ZigBee的无线嵌入式通信模块经过量产测试,正式在市场上销售并成功应用于多种工业监控项目,市场反响良好。
[Abstract]:With the development of the Internet of things technology, the level of industrial production information is becoming more and more high, managers need to be able to grasp the production situation at any time. At present, the communication network wiring of industrial production is mainly through RS232 CAN, Ethernet and other traditional wired methods, although it can meet certain requirements. However, due to the rapid upgrading of production equipment, resulting in higher and higher costs, wireless devices will be introduced into the field of industry instead of wired communications. It has a certain significance in reducing the cost of system upgrade and making the system upgrade more flexible. At present, wireless sensor network technology is relatively mature, has been successfully applied in the intelligent transportation, intelligent medicine and environmental monitoring and other industries. Domestic research on wireless sensor networks and Internet of things related technologies has developed rapidly in recent years with the support of national policies. This paper uses the CC2530 chip of Texas Instruments Company as the main control chip, and combines ZigBee wireless technology, low power design, time synchronization technology, serial communication technology and so on. A set of embedded wireless communication module based on ZigBee communication technology is designed and implemented by the idea of embedded hardware and software co-design. The module is embedded into the PLCU HMI, which is widely used in the existing industrial system, and the industrial PC is integrated to form the wireless industrial communication network. The hardware circuit of the system takes CC2530 chip as the core, adopts embedded modularization design, and designs two kinds of equipment. RTC module and analog switch are used to control the power supply of CC2530 to overcome the disadvantage that ZigBee routing equipment can not enter dormancy. In order to reduce the overall power consumption of the system, the module provides common communication interface between RS232 and RS485. The software of the module is completed on the basis of TI's Z-Stack protocol stack, and adopts multi-task parallel processing mechanism, including protocol data conversion. Time synchronization protocol service, wireless communication, serial communication and other tasks, each task by setting event flag synchronization. Using MODBUS station number and ZigBee network address binding. An address mapping table is formed to complete the conversion of two protocol data. Data exchange and gateway function between MODBUS network and ZigBee wireless network are completed. PTP precise time synchronization protocol is used to complete the time synchronization of network nodes. Add the response of PTP service in MAC layer and trigger to read hardware timestamp information to improve the accuracy of time synchronization of system node. In this paper, the transmission power of the hardware part of the module is 2 dBm, the receiving sensitivity is -98 dBm, the communication link budget is 100 dBm, and the actual reliable communication distance is 100 m. The actual operating current of low power module in dormant state is only 400nA of RTC chip BL5372, and the communication rate of the module is 219kbs. The communication packet error rate is about 0.1%, the time synchronization accuracy is 50 us. and the fluctuation is small. The wireless embedded communication module based on ZigBee is tested by mass production. Officially sold in the market and successfully applied to a variety of industrial monitoring projects, the market response is good.
【学位授予单位】：江南大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：TP368.1

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