介绍了一种基于单片机的区域交通信号控制系统设计方案,阐述了系统的工作原理及各主要模块的软硬件实现方法。系统能够根据车流量信号动态地改变交通信号灯各状态配时,并通过无线通信技术,有效地解决了特定区域内各路口信号机之间数据的传输,实现了区域交通信号的智能控制。该系统抗干扰能力强,可靠性高,使用非常方便。
上传时间: 2013-10-21
上传用户:kinochen
在理论分析循环码编码和译码基本原理的基础上,提出了基于单片机系统的(24,16)循环码软件实现编码、译码的方案。仿真结果表明(24,16)循环码能有效地克服来自通讯信道的干扰,保证数据通信的可靠及系统的稳定,使误码率大幅度降低。本论文对(24,16)循环码的研究结果表明,可以有效地降低错误概率和提高系统的吞吐量,实现纠错仅需要在接收端增加有限的存储空间和计算复杂度,具有一定的实用价值。 Abstract: Based on analyzing the theory of encoding and decoding of cyclic code, this paper showed the schemes of encoding and decoding of(24,16)cyclic code by the software and based on microcontroller. Simulation results show that using (24,16) cyclic codes can effectively overcome the interference from communication channel, ensure the reliability and stability of data communication systems, and reduce the bit error rate greatly. The results of this paper show that by using the (24,16) cyclic code, the error rate can be reduced and the system throughput can be improved. Meanwhile, the system only needs to enlarge limited storage space and computation the complexity at the receiving end to realize error correction. Thus the (24,16) cyclic code has a practical value.
上传时间: 2013-11-09
上传用户:gaoliangncepu
多媒体手机在满足传统语音通信的同时还必须提供稳定、高质量的多媒体表现,传统的单处理器方案不能满足这些并行任务的处理能力要求,采用具有视频、Java和安全专用硬件加速器的多处理器引擎系统级芯片能有效解决这些多媒体任务要求,并能有效降低系统功耗。 手机正在成为手持式娱乐中心,同时作为高端的宽带无线电话使用。用户携带手机是为了使用其无线功能,但同时也希望它具有PDA、MP3播放器、数码相机、摄像机、视频播放器和游戏机功能。然而,开发这样的一个多媒体设备具有更大的技术挑战,特别是在服务质量、反应速度和电池寿命等关键性能方面。解决这些问题的方法是将多个处理引擎集成到系统级芯片中。
上传时间: 2013-11-25
上传用户:yepeng139
提出了一种可根据环境光强、红外和温度变化而实现自动开关、调节亮度的LED照明系统的设计方案。采用单片机C8051F020为系统控制核心,设计了由硅光电池和集成运放组成的光强传感器,选用热释电模块作为红外无线感应器,采用DS18B20为温度传感器,还利用液晶实现了工作信息显示。实验结果表明,系统在光强大于2 170 lx或温度高于82.5 ℃时能自动关断,当光强小于1 040 lx或温度低于49.3 ℃时能自动开启;当光强在1 000~2 000 lx变化时,LED亮度能自动调节,以维持环境照度基本稳定。
上传时间: 2013-10-10
上传用户:xaijhqx
为提高温度测量效率,降低系统的成本,扩展传输距离,设计出一种新型温度采集系统。单片机通过控制具有单总线方式的温度传感器DS18B20实现对温度的测量,同时单片机通过控制具有单总线方式300~450MHz频率范围内的MAX7044与MAX7033无线发射与接收芯片实现温度数据的无线传输。与传统温度采集系统相比,该系统利用单总线方式连接,采用无线传输方式实现远距离通信,易于系统的集成与扩展。实验结果表明,该系统结构简单、方便移植,能够同时实现多达上百点温度的测量与500m范围的传输。 Abstract: To improve the temperature measurement efficiency and reduce system cost,expansion of transmission distance,a new type of temperature acquisition system is designed.Microcontroller controlled temperature sensor DS18B20which has a single-bus achieves temperature measurement,while microcontroller by controlled the MAX7044and MAX7033chip with a single-bus and having300~450MHz radiofrequency to achieve the wireless transmission of temperature data.Compared with conventional temperature acquisition system,the system uses single-bus connected,and uses wireless transmission means to achieve long-distance communications,easy-to-system integration and expansion.The experimental results show that the system is simple,convenient transplantation,and can be implemented in as many as a hundred-point temperature measure-ment and the transmission range of500meters.
上传时间: 2013-10-29
上传用户:515414293
介绍一种以Atmel公司的Attiny13为处理器的投影仪防盗器设计方案。该防盗器具有功耗低,功能完整,防盗效果良好等特点,除具有报警功能外,防盗器还具有以无线方式向主机发送报警信号的功能。采用315MHz发射模块实现无线信号发送。该投影仪防盗器可适应众多厂家生产的防盗器主机。 Abstract: This paper introduces the design scheme of overhead projector's anti-theft device which users ATMEL company’s Attiny13as processor.This anti-theft device features low powerloss,functional integrity,good effect of anti-theft.In addition to its own with alarm functions,the anti-theft device also has alarm function which can send alarm signal to the host through wireless way.It sends wireless signal using315MHz transmitting module,so this overhead projector’s anti-theft device is adapted to anti-theft device host produced by many manufacturers.
上传时间: 2013-11-02
上传用户:ysystc699
CANopen主节点除具备CANopen设备的基本条件外,还需具备NMTMaster的功能,即对CANopen网络进行管理。对CANopen主节点的实现提出三种方案:方案1:在CANopen-Chip基础上开发CANopen主站。方案2:通过对CANopen协议栈源代码的二次开发在单片机上实现嵌入式CANopen主站。方案3:利用CANopenMasterAPI在PC机上实现CANopen主节点。
上传时间: 2013-11-02
上传用户:luke5347
介绍一种简单射频识别系统设计。该设计包括阅读器、应答器和线圈3部分。由单片机控制阅读器向应答器发射无线信号,并接收应答器回送的信号,再通过分析回送信号识别物品。阅读器和应答器之间以半双工通信方式通信。 Abstract: A simple design of radio frequency identification system is given in this paper.The design includes reader,responder and winding.Through MCU,signals are sent to responder from reader,then corresponding signals are sent back. According to the analysis of the signals sent back,the objects can be identified.Half-duplex communication is adopted? between? reader? and? responder.
上传时间: 2013-10-11
上传用户:plsee
基于幅移键控技术ASK(Amplitude-Shift Keying),以C8051F340单片机作为监测终端控制器,C8051F330D单片机作为探测节点控制器,采用半双工的通信方式,通过监控终端和探测节点的无线收发电路,实现数据的双向无线传输。收发电路采用直径为0.8 mm的漆包线自行绕制成圆形空心线圈天线,天线直径为(3.4±0.3)cm。试验表明,探测节点与监测终端的通信距离为24 cm,通过桥接方式,节点收发功率为102 mW时,节点间的通信距离可达20 cm。与传统无线收发模块相比,该无线收发电路在受体积、功耗、成本限制的场合有广阔的应用前景。 Abstract: Based on ASK technology and with the C8051F340 and C8051F330D MCU as the controller, using half-duplex communication mode, this paper achieves bi-directional data transfer. Transceiver circuit constituted by enameled wire which diameter is 0.8mm and wound into a diameter (3.4±0.3) cm circular hollow coil antenna. Tests show that the communication distance between detection and monitoring of the terminal is 24cm,the distance is up to 20cm between two nodes when using the manner of bridging and the node transceiver power is 102mW. Compared with the conventional wireless transceiver modules, the circuit has wide application prospect in small size, low cost and low power consumption and other characteristics.
上传时间: 2013-10-19
上传用户:xz85592677
为了提高环境参数采集的自动化水平,提升效率,设计了无线传感器系统。本系统运用了传感器技术、通信技术和单片机技术,实现了对环境温度、湿度、光照度以及可燃性气体浓度等参数的检测。它能够实时地与上位机进行无线通信,满足对环境参数实时监测的要求。 Abstract: In order to increase the degree of automation and improve the efficiency of the environment monitoring parameters,the wireless sensor system was developed.Combining with the technique of sensor,automatic monitoring,communication and single-chip microcomputer,it realized real-time monitoring environment parameters,such as temperature,humidity,illumination,concentration of com- bustible gas and so on.At the same time it can communicate with upper personal computers,satisfy the desire of real-time monitoring.
上传时间: 2013-11-22
上传用户:longlong12345678