共查询到20条相似文献，搜索用时 464 毫秒
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面向移动校讯通的短信收发系统的设计与实现 总被引：1，自引：0，他引：1
介绍一个面向移动校讯通的短信收发系统的设计与实现。在分析短信收发原理的基础上,设计了短信收发系统。利用GSM设备实现了短信收发功能,并在学校与家长沟通中获得良好的应用。 相似文献
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从机房收发电子作业所采用的一般方法人手,重点阐述了后台服务器设置、学生工作站操作、教师收发作业操作过程及其他如PHP／JSP等大众化的网页收发电子作业操作思路,证明了利用ASP服务器端收发学生作业这种方法,具有明显的实用、借鉴和参考价值。 相似文献
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黄小芬 《福建工程学院学报》2013,11(4)
由单片射频收发芯片nRF24E1和短信收发模块TC35组成的智能家居远程监控系统,通过嵌入51单片机内核的单片射频收发芯片nRF24E1构成星形结构网络,采集、处理以及无线收发家居中可能出现的意外情况并利用GSM模块的短消息收发功能,实现远程安防监控和家电控制. 相似文献
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本文介绍了“小飞侠考试改卷系统”收发作业的功能,“小飞侠”为收发课堂作业文件提供了一套既安全又灵活的方法,方便老师收发课堂作业。 相似文献
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该文主要介绍了利用JF24D高频率发射信号模块和接收信号模块设计的单群机无线二进制码的无线通讯短信收发系统的通信技术.该通讯系统设计采用的是目前流行的无线传输TD-LTE技术,在高频率发射和接收信号模块的基础上实现了任意两机之间的短信数据收发通信,以及单机系统对群机系统的数据收发通信技术.该系统设计主要分为硬件电路设计、软件系统设计和无线通讯信号收发模块设计三个方面.系统设计的方法主要包括收发信号编解码技术、无线通讯协议技术、收发信号防干扰技术、短信编写技术和IPS液晶显示屏显示技术等. 相似文献
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nRF2401是Nordic公司推出的单片2.4GHz无线收发一体芯片,只需少量外围元件便可组成射频收发电路,可以方便地使用在无线控制系统中。文章主要介绍在PIC单片机中使用nRF2401收发数据的硬件电路及其PICC语言的详细实现。 相似文献
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淀粉们都是怎样登录邮箱收发邮件的？
A、当然是登录网站首页,再按部就班……
B、使用邮件客户端工具来收发邮件。
C、对于这个问题,我很困惑。
选什么呢？相信还是选A或B的淀粉居多。但如果你选C。找不到一个更完美的收发邮件的方法,那不妨来试试下面这个方法吧!把邮箱的快捷方式请到桌面上,让收发邮件更快捷自如（以163邮箱为例）! 相似文献
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天线实验教学仿真系统的研究 总被引：4，自引：0，他引：4
采用Visual Basic软件开发工具设计并实现了天线实验教学仿真系统。首先给出了系统的构成,讨论了天线模型的建立、天线方向性图和天线输入阻抗的测量,最后介绍了系统的软件实现过程。所设计的天线实验教学仿真系统实现了天线的方向性图和输入阻抗的测量过程。应用表明,天线实验教学仿真系统具有交互性好、实用和逼真等特点。 相似文献
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介绍天线调谐器反Г形阻抗匹配网络的结构形式和匹配区域;分析反Г形网络各参数取不同值时对HF双极天线的适配性,给出参数变化随频率、VSWR门限变化时对HF双极天线输入阻抗的适配曲线,为设计天线调谐器阻抗匹配网络和决定天线调谐器适配天线类型提供参考． 相似文献
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Characteristics of a single-feed dual-frequency bow-tie microstrip antenna are studied. By using the variation method, simple formulas for resonant frequencies of the bow-tie microstrip antenna are derived. It is shown that the dual-frequency ratio can be controlled easily by choosing the parameters of the antenna. This design gives compact antenna size and simple antenna structure. Experimental results are presented, verifying the validity of the design. 相似文献
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温煜东 《晋城职业技术学院学报》2013,(6):59-61
本文设计了一种应用于无线局域网的电磁带隙结构(EBG)的微带天线。通过在微带贴片天线的辐射单元周围加载蘑菇型EBG结构,使得天线的带宽、增益性能得到了显著改善。仿真结果表明,与普通贴片天线相比,加载EBG结构时天线带宽增加了6%,主辐射方向上增益增大了1.98dB。 相似文献
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ZHU Fang-ming HU Jun 《浙江大学学报(A卷英文版)》2007,8(2):192-196
INTRODUCTION Metamaterials are periodic metallic structures exhibiting unique properties not existing in natural materials. They are also called backward wave mate- rials, double negative materials, or left-handed mate- rials (LHM) in particular, in which the vectors E, H and k form a left-handed system. Since the idea pro- posed by Veselago (1968), metamaterials have at- tracted great interest in the last years (Smith et al., 2000; Pendry, 2000; Smith and Kroll, 2000; Shelby et al., … 相似文献
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To establish wireless channel suitable for the cabin environment, the power coverage was investigated with distributed antenna system and centralized antenna system based on the actual measurement of channel impulse response. The results indicated that the distributed antenna system has more uniform power coverage than the centralized antenna system. The average relative errors of receiving power of both antennas were calculated. The optimal position of the centralized antenna was obtained by Gaussian function refinement, making the system achieve a better transmission power with the same coverage effect, and providing a reference for antenna location in the future real communication in the cabin. 相似文献
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MEHTA Amit 《浙江大学学报(A卷英文版)》2007,8(12):1901-1904
A dual S shaped micro strip antenna with a realistic feed is proposed for generation of tilted beam radiation pattern pertaining for beam steering applications. To achieve this, four feeding points are located at a distance of 5.6 mm from the antenna centre. These feeding points when excited one by one generate four tilted beams in four different space quadrants, thus yielding a beam steerable antenna. Importantly, since the proposed antenna is symmetrical in the structure, all the four tilted beams have the same radiation pattern characteristics. A further enhancement of the antenna bandwidth is also achieved using 100-μm capacitive coupling between the feed and the antenna strip. 相似文献
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A simple and compact ultra wideband (UWB) printed monopole antenna with band-notched performance is proposed in this paper. The antenna is partially grounded so that the Q value is depressed and the impedance bandwidth is broadened. A small strip bar is loaded on each arm of the similar U-shaped radiator. The impedance bandwidth of the antenna overlap with IEEE 802.11a is rejected consequently. The geometry parameters of the antenna are investigated and optimized with HFSS. The measured bandwidth of the proposed antenna occupies about 7.89 GHz covering from 3.05 GHz to 10.94 GHz with expected notched band from 4.96 GHz to 5.98 GHz. A quasi-omnidirectional and quasi-symmetrical radiation pattern in the whole band is also obtained. As a result, a UWB wireless communication system can be simplified with the band-notched UWB antenna presented. 相似文献
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本文在基片集成波导腔体结构的基础上,结合共地共面波导结构,提出了一种低剖面带宽增强型背腔缝隙天线．本天线兼具传统金属波导缝隙天线辐射效率高、功率容量大以及传统微带缝隙天线体积较小的优点,同时还具有了低剖面、重量轻、易于与平面电路集成的特点．仿真结果显示,该天线中心工作频率为5．8GHz,最大增益6．9dBi,相对带宽2．25％,完全覆盖5．8GHz频段,适用于RFID应用． 相似文献
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介绍了CATV系统卫星接收天线与引向天线的工作原理;讨论了引向天线有源（或无源）振子大小、间距与频道的关系,并以表格的形式推出了3种多单元引向天线的一系列参考数据。 相似文献