基于ARM_Linux和太阳能充电的有源RFID系统设计

发布时间：2018-05-01 14:15

本文选题：有源RFID + 太阳能　；参考：《电子科技大学》2014年硕士论文

【摘要】：2.45GHz有源RFID系统具有通信距离远、天线尺寸小、频段免注册等优点。随着由电子科技大学牵头组织的2.45GHz ISO/IEC18000-4标准制定工作的逐步推进,2.45GHz RFID系统在国内必将得到更广泛的推广。目前的有源RFID系统用于户外跟踪或监测物体时,在节能、管理和实用性方面还有许多不足。本文基于此,设计了基于ARM_Linux和太阳能充电的有源RFID系统,它采用环保的太阳能供电,具有防拆卸、防冲突功能,同时还有高效率管理的蓝牙报警功能和远程网络访问功能。本文首先分析了RFID技术的发展状况和从环境中获取能量的一些方式;然后详细地分析了实际应用中RFID系统的需求,并基于此设计了系统的整体框架。在电子标签的设计中对系统的主控芯片和射频芯片进行了调研分析,最终选择了MSP430F2121作为主控制器,nRF24L01芯片作为射频模块的核心,太阳能电池和锂电池作为供能和储能元件。由于采用了CN3063电池管理芯片使得读写器的太阳能供电系统能够自动完成充放电管理,同时对太阳能供电系统的电压进行了测试,可用于电子标签供电,延长了电子标签的使用寿命。对电子标签的拆卸报警功能和防碰撞功能进行了研究:通过一个开关来控制电子标签与所跟踪物体的状态,为了使这个报警信息能够快速告知管理人员,在读写器中扩展了蓝牙模块,通过它把这个报警发送给管理人员的手机。对于防碰撞功能通过ALOHA算法和分配信道的方式来降低数据包冲突的概率。读写器采用S3C2440A作为CPU,DM9000作为以太网控制器,同时在读写器上移植Linux嵌入式操作系统、BOA服务器和SQLite3数据库,并开发nRF24L01射频模块的驱动程序。在CGI程序设计中采用Posix消息队列给读写器的射频接收单元传递命令,利用多线程的方式对接收到的数据进行处理。读写器通过数据库存储电子标签的数据,编写HTML应用程序之后,可以通过Web浏览器访问电子标签所采集到的温度信息。最后,对电子标签的天线和通信距离进行了理论分析和实际测试,整个系统工作状态良好,读写器与电子标签的最大稳定通信距离可以达到120m,当两者之间有防碍物时,通信距离会减小。
[Abstract]:2.45GHz active RFID system has the advantages of long communication distance, small antenna size and free registration in frequency band. With the development of 2.45GHz ISO/IEC18000-4 standard, led by the University of Electronic Science and Technology, the 2.45GHz RFID system will be popularized more widely in China. The current active RFID system has many shortcomings in energy saving, management and practicability when it is used to track or monitor objects outdoors. Based on this, this paper designs an active RFID system based on ARM_Linux and solar charging. It uses environmental protection solar power supply, has anti-disassembly and anti-conflict functions, and also has the Bluetooth alarm function of high efficiency management and remote network access function. This paper first analyzes the development of RFID technology and some ways to obtain energy from the environment, then analyzes the requirements of RFID system in practical application in detail, and designs the overall framework of the system based on this. In the design of electronic tag, the main control chip and radio frequency chip of the system are investigated and analyzed. Finally, MSP430F2121 is chosen as the core of the main controller nRF24L01 as the core of the RF module, and solar cells and lithium batteries are used as the energy supply and energy storage components. Because of the use of CN3063 battery management chip, the solar power supply system of the reader can automatically complete the charge and discharge management. At the same time, the voltage of the solar power supply system is tested, which can be used to supply power with electronic label. Extended the service life of electronic label. In this paper, the disassembly alarm function and anti-collision function of electronic label are studied. A switch is used to control the status of the electronic tag and the object being tracked, so that the alarm information can be quickly informed to the manager. The Bluetooth module was extended in the reader to send the alarm to the manager's mobile phone. For anti-collision function, the probability of packet collision is reduced by ALOHA algorithm and channel allocation. The reader adopts S3C2440A as the Ethernet controller, at the same time, the Linux embedded operating system S3C2440A server and SQLite3 database are transplanted on the reader, and the driver of nRF24L01 RF module is developed. In the design of CGI program, the Posix message queue is used to transmit commands to the RF receiving unit of the reader, and the received data is processed by multithreading. The reader stores the electronic tag data through the database, and after writing the HTML application program, it can access the temperature information collected by the electronic tag through the Web browser. Finally, the antenna and communication distance of the tag are analyzed theoretically and tested in practice. The whole system works well, and the maximum stable communication distance between the reader and the tag can reach 120 m, when there is an obstacle between the two, The communication distance will be reduced.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TP391.44;TM615

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