摘要
随着科学技术的不断发展，人们对现代化办公场所和生活起居提出了更高层次的安防需求，智能门禁系统逐渐取代普通的门锁，手工出入管理已经不能适应现代化管理的实际需求。 本文以深圳职业技术学院横向项目“远距离无线门禁系统开发及安装维护”的研究成果为支撑，通过理论研究和工程实践，研制出了2.4G无线门禁控制系统。论文的创新工作主要有： (1) 根据无线门禁系统使用需求设计了硬件系统。通过移植μC/OS-II嵌入式系统，实现了16个任务分8级调度。通过对nRF24LE1和MF RC522射频电路的研究，提升了2.4G传输模块传输距离和CPU卡读卡模块读卡稳定性。 (2) 针对无线门禁网络节点不需要移动的特点，使用静态路由技术，无线网络以节点为中心向外辐射，以-64dbm作为辐射半径，展开无线网络。最后使用OMNET++4.0仿真了30个门禁节点的无线网络，通过仿真实验对无线网络节点数据接收量、各级节点数据吞吐量、节点数据包发送延迟、节点待发数据队列深度等组网参数进行了分析，确定了存储容量和传输时间参数。 (3) 为了解决远距离RFID系统出现碰撞的问题，提出了一种新型Q+值防碰撞算法，解决了大量电子标签同时回复一个阅读器而产生碰撞的问题，降低了读卡的平均时延。仿真实验验证该算法的可行性和有效性。
本文在实验室环境下，对2.4G无线门禁控制系统已进行硬件和软件测试。实验数据验证2.4G无线门禁控制系统的稳定性，为无线门禁控制系统的进一步研究奠定了基础。
关键字：无线门禁网络；μC/OS-II；OMNET；远距离RFID系统；Q+值防碰撞算法
Abstract
With the continuous development of science and technology, a higher level of security management of modern office space and living accommodation is needed, the common door lock system is gradually replaced by intelligent access control systems, manual access control can not meet the actual needs of modern management.
In this paper, based on the business project of Shenzhen Polytechnic “long-distance wireless access control system development and installation and maintenance”, with theoretical analysis and engineering practice, a 2.4G Wireless Access Control System is developed. The main innovation of the paper includes:
(1) The hardware system is designed by the demands of wireless access control system. By transplantting μC/OS-II embedded systems to achieve 8 levels scheduling of the task. The performanc
e of the 2.4G transmission module and the CPU card reader module are enhanced through the study of nRF24LE1 and MF RC522 circuit.
(2) Aiming to the characteristics of wireless nodes do not need to move, wireless network is used as the static routing technology, consider the base node as center, using -64dBm signal strength as the transmission radius. At last, the OMNET are used to simulate the wireless network which has 30 nodes. The simulation results can be analysed the amount of base station node data, the amount of throughput data at all levels of nodes, the packet transmission delay of node, the waiting queue depth of data in the node and so on. The communications protocol ensures the reliability of the system capacity and transmission time parameters.
(3) In order to solve the tag collision problem in long distance RFID systems, an enhanced Q+ Anti-collision algorithm is proposed. The new algorithm solved the problem which a large number of electronic tags replyed a same reader will come out collision, and reduced the average reader delay of cards. The algorithm's reliability has been proved by the simulation results.
2.4G wireless access control had debugged the system hardware and software in the laboratory environment. The reliability of 2.4G wireless access control system had proved by the experimental dat
a, and it laid the foundation for further research and development of wireless access control system.
Key word: Wireless access networks;μC/OS-II;OMNET; Long distance RFID systems; Q+ Anti-collision algorithm;
目录
摘要 ............................................................................................................................ I ABSTRACT .................................................................................................................. II 第1章绪论 .. (1)
1.1课题研究的背景及意义 (1)
1.2无线门禁国内外现状及发展趋势 (2)
1.2.1国外发展现状及发展趋势 (2)
1.2.2国内发展现状及发展趋势 (2)
1.3本文主要研究内容与章节安排 (4)
1.3.1本文主要研究内容 (4)
1.3.2本文章节安排 (4)
第2章无线门禁系统整体方案设计 (5)
2.1系统整体方案 (5)
2.1.1无线门禁系统安装方案 (5)
2.1.2无线门禁的工作过程 (6)
2.2门禁系统控制板硬件设计 (7)
2.2.1 MCU芯片选型 (8)
2.2.2实时时钟设计 (9)
2.2.3存储模块设计 (9)
2.2.4 LCD显示模块设计 (10)
2.2.5 CPU卡读卡模块设计 (10)
2.2.6 2.4G无线传输模块设计 (11)
2.3μC/OS-II嵌入式系统移植 (13)
2.3.1无线门禁工作状态 (13)
2.3.2用户身份验证 (14)
2.3.3数据存储管理 (15)
2.3.4电锁开关检测 (15)
2.3.5无线数据传输 (16)
2.3.6任务调度优先级 (17)
2.3.7软件系统移植 (19)
2.4射频PCB设计 (20)
2.4.1 PCB电源的处理 (20)
2.4.2 PCB地的处理 (21)
2.4.3阻抗匹配 (23)
2.4.4射频板基材的选型 (25)
2.4.5 2.4G模块的天线设计 (25)
2.4.6 13.56MHz无线读卡模块设计 (27)
2.5本章小结 (29)
第3章无线网络通信协议设计 (30)
3.1无线网络数据链路层 (30)
3.1.1差错控制方式 (31)
3.1.2差错控制编码 (31)
3.2无线数据帧设计 (32)
3.3无线门禁组网描述 (33)
3.3.1网络地址分配 (33)
3.3.2网络路由建立 (34)
3.4网络数据访问控制方式 (36)
3.5OMNET++网络仿真 (37)
3.6本章小结 (41)
第4章RFID防碰撞算法设计 (42)
4.1RFID碰撞产生原因 (42)
4.2RFID系统中的防碰撞算法 (43)
4.2.1 Q值算法 (44)
4.2.2 Q+值算法 (45)
4.2.3 C值的改进 (46)
4.2.4算法性能分析 (48)
4.3本章小结 (49)
第5章无线门禁系统测试 (50)
5.1无线门禁硬件测试 (50)
5.1.1 MCU在线测试 (50)
5.1.2存储模块读写测试 (51)
5.1.3串口传输测试 (52)
5.1.4天线驻波比测试 (52)
5.1.5无线信号检测 (53)
5.1.6有源标示卡通信距离测试 (53)
5.2无线门禁软件测试 (54)
5.2.1系统上位机测试 (54)
5.2.2无线门禁系统读卡测试 (55)
5.2.3 RFID系统读卡测试 (55)
5.2.4无线门禁网络测试 (57)
5.3无线门禁装置 (58)
5.4本章小结 (59)
第6章总结与展望 (60)
参考文献 (61)
个人简历、在学期间发表的学术论文与研究成果 (65)
豫公网安备41160202000603
站长QQ:729038198
关于我们
投诉建议