基于射频识别技术的门禁系统的设计(终极版)

（4）The Design including watchdogs, LCD, data storage and real-time clock module, and other peripheral circuits, using serial design such as SPI, I2C, thus saving the MCU's I / O interface. Access Control System Design at the same time combining the access control circuit, completed the equipment selection.
RFID with convenient and efficient becomes the focus of attention of the industry, andChinais being an RFID tag production of the most promising production base.
（1）研究了基于射频识别技术的门禁系统的总体设计，设计了射频IC读卡器的电路原理图，给出了PCB板。读卡器主要由射频天线、读卡模块、RS485通信接口及单片机控制系统组成，能读写Philips公司的Mifare非接触式智能射频卡，读卡距离约10cm。当没有卡进入读卡能量范围时，系统显示时钟，当有卡进入时则读卡内数据并将卡号信息显示在液晶显示器上。
Keywods：Access Control System；Radio Frequency Identification；MF RC500；Proximity Coupling Device；Serial Communication.
1.2国内外研究发展现状2
1.3本文主要研究内容3
第2章门禁系统的技术基础5
3.2系统硬件模块分析17
3.2.1射频读写模块分析17
3.2.2其他部分硬件分析18
3.3射频读写模块设计19
3.4直接匹配天线20
3.4.1 EMC电路20
3.4.2接收电路20
3.4.3直接匹配天线的天线匹配电路21
3.5 RS485通讯模块25
3.5.1RS485接口26
3.5.2RS485网络拓扑结构27
2.1射频识别技术5
2.1.1射频识别技术原理5
2.1.2RFID天线6
2.1.3射频识别系统的典型结构8
2.1.4RFID同其它自动识别技术的比较9
2.2门禁系统结构原理10
2.3密码技术12
第3章基于射频识别的门禁系统总体设计16
3.1系统总体方案设计16
3.1.1系统设计的基本要求16
3.1.2系统方案17
射频识别以其方便快捷成为业界瞩目的焦点，而中国正在成为射频识别标签生产最被看好的生产基地。将射频识别应用到门禁系统，具有广泛的应用前景，本文基于这一思想设计了小型门禁系统的底层模块，同时还有待于进一步研究扩展，比如利用Internet接入取代RS485联网方式，扩大系统的规模。
关键词：门禁系统；射频识别；MF RC500；读卡器；串口通信
（4）设计单片机的包看门狗、液晶显示、数据存储和实时时钟等在内的外围模块电路，采用串口设计如SPI、I2C等，从而节约了单片机的I/O接口。同时结合门禁系统设计门禁控制电路，完成设备的选材。
（5）根据射频识别门禁系统总体设计要求，采用模块化软件设计方法，根据MF RC500的特性，系统地对MF RC500芯片的操作流程进行研究，设计主程序的流程图和各个模块子程序，使用C51语言开发了读写器的底层控制软件，并完成程序的调试，证明结果满足设计要求。
（5）Tomeet the Radio Frequency Identification Access Control System design requirements ,we design by modular software method. According to the characteristics of MF RC500 and the systematic research on the operation of MF RC500 chip process, design the flow chart of the main program modules subroutine, use C51-language development the bottom of the reader control software, and completed the debugging process that results meet the design requirements.
（2）深入研究RFID天线的EMC过滤器、接收电路以及天线匹配电路等构成，结合本设计采用了线圈天线，并从品质因素Q和调谐频率两方面设计读写器天线，设计优化了天线耦合电路。
（3）针对设备组网应用要求，门禁终端通信采用RS485总线，同时结合门禁读卡器研究了RS485的网络拓扑结构，通过RS485接口与PC机组成通信网络系统。读卡器平时可独立工作，PC机会每隔一定时间访问读卡器，用PC机上的时钟统一校准读卡器上的时钟，并读取存储器内的读卡数据，以便读卡器中的数据得到及时处理。
Applicated Radio frequency identification to the Access Control System, has broad application prospects. Based on this thinking, this paper gives out the realization of the specific design, but also to be further study on the expansion, such as the use of Internet access to replace RS485 interconnection, expanding the size of the system.
3.6外围接口电路29
3.6.1看门狗电路29
3.6.2液晶模块31
3. 7数据存储的硬件设计35
3. 7. 1数据存储器的接口36
3. 7. 2I2C总线协议36
3.8实时时钟的硬件设计37
3. 8. 1实时时钟的接口37
（3）Regard theApplication for network equipment requirements,Access Control Terminal using RS485 communications, while combining Access Control RS485 reader on the network topology, through the RS485 interface and PC component communication network system. Reader peacetime can work independently, PC every opportunity to visit some time reader, with PC clock reunification on the clock calibration reader, and the memory card reader to read data to the reader to obtain timely data processing.
（2）Deeply studed the RFID antenna EMC filters, receive circuit and antenna matching circuits, etc., and considering the special design,we use the coil antenna ,optimize the coupling circuit by raise the quality factor Q and the frequency tuning.
（1）This paper introduces the design of the Access Control network system based on radio frequency identification IC card, which analysises the design of hardware detailedly, gives out the electric circuit principle diagram of making contactless IC cardProximity Coupling Device（PCD）. The PCD is consisted of RF antenna, read/write module, RS485 communication interface and MCU, which can read/write the Mifare contactless Smart Card of Philips company, the distance of reading card is10 cmroughly.The system will display the clock when there is no card entered into the scope of RF energy；when the card entered into that, the reading card data will be displayed.
Abstract
To meet the needs of the information age, ensuring security of the internal architecture and the users different kinds of needs , entrance guard system comes out Gathered with computer technology, electronic technology, mechanical technology, magnetic-electric technology and radio frequency identification technology, Access Control System makes card and locks get " integrity dialogue" function. That smart cards to control the open or close of the doors ,introduces a new management concept , which not only manager can provide a safe, faster, more automated management style, but also offer the users, a great convenience. In this paper, we research on the design of radio frequency identification Access Control System.