短距离无线网络通信技术及其应用(论文17000字)
摘 要
如今，短距离无线通信技术日益热门，并且蓝牙已有了国际标准。本文主要对蓝牙相关知识以及理论进行了探讨，例如其原理、结构以及方案等，针对其中存在的不足，提出了一些相关建议，使得短距离无线通信更加的简便高效。
在无线接受以及发送方面，本系统使用DSSS技术，频率为2.4GHz ISM频段，文章不仅阐述了用于短距离无线通信的扩频技术，分析了一些伪随机码对于扩频通信的使用，还展现出了本系统中的硬件电路框图，其主要用于物理层，另外还阐述了相关芯片组的原理，并基于此设计并测试了无线收发电路。
设置在无线通道之上的数据链路层，含有MAC和LLC这两层。文中对LLC层所实现的的基本功能做了阐述，例如差错以及流量控制等，并且对无线网络中常常出现的MAC协议进行分析，随后对本系统所用的MAC协议的控制程序进行了分析，并且展现了数据链路层采用的硬件电路框图，因为本系统是在MCU上通过编程来实现协议的，因此对其软件流程也进行了分析。
【关键词】无线通信 DSSS MAC协议 蓝牙 CSMA
Abstract
In today's power has been integrated into our homes, is a powerful support for China's economic development. But the grid system is stable and safe development of our country threatened by reactive power greatly, and even now have been on the further development of electric power system had a great effect. So reactive power compensation has now become the development of intelligent power grid and enhance the utilization efficiency of key research projects, especially without power real-time J fast and very precise compensation for the development of the power grid in China also has very important significance. But because of the traditional reactive power compensation equipment compensation technology is quite backward, and so now if you want to meet the standards of compensation network is unlikely. But along with our country about the innovation and development of electric technology, about static reactive power compensation of static var generator (svG) devices have been successfully developed, because it has a fast response, high control precision, dynamically continuous compensation and restrain the voltage fluctuation and flicker is quite perfect performance, so it has become a flexible ac transmission system devices is quite important.
This paper first for the reactive power compensation device development present situation and the domestic and foreign research status quo of svG makes a simple introduction, and then analyzes the theoretical principle of the svG reactive compensation, finally to svG movement characteristics on the theoretical analysis and stability, the analysis model for mathematical model. In this paper, using reactive current tests for reactive current signal, the method is in d - q under the premise of the positive and negative double sequence of coordinate transformation. In order to achieve the purpose of strengthen the control performance of the SVG, this paper now SVG all kinds of the most commonly used control method has carried on the quite serious research and analysis, and considering their advantages and disadvantages of different and the situation of the unbalanced load, the final design out a way to control the power imbalance, this method is based on d - q coordinate transformation under the premise of positive and negative double sequence control, not only can complete real-time dynamic compensation of reactive power current, but also for the negative sequence current produced by the unbalance of system has very effect.
Based on the theory of SVG research foundation, and MATLAB is a powerful simulation effect, create the SVG system simulation model. And did a lot of related dynamic simulation experiment, the purpose is to verify the above mentioned reactive current test and control strategy, and concluded that SVG has very strong dynamic performance, it can achieve the effect of reactive power compensation, the negative sequence current and the blocking effect of each parameter are comply with the design requirements. Finally simulation analysis based on SVG device for the design of the hardware circuit and the selection, so as to set up a small test platform, and for some finished writing and debugging software control program.
Key words: reactive power compensation, static reactive power generator, d - q coordinate transform, instantaneous reactive power and reactive current detection，Unbalanced load
目录
摘 要 II
Abstract III
目录 IV
第一章 绪论 1
第一节 研究背景 1
第二节 短距离无线通信的相关解决方案 1
第三节 本文的工作 4
第二章 短距离无线通信的主要标准 5
第一节 蓝牙技术概述 5
第二节 蓝牙系统的体系结构 6
一、 蓝牙的底层模块 7
二、 中间协议层 7
三、 高端应用层 8
第三节 蓝牙的实现 9
一、 单芯片实现方案 9
二、 两芯片组方案 11
第四节 目前蓝牙的不足之处 12
第三章 无线网络的物理层 14
第一节 对整个系统的介绍 14
第二节 在2.4GHz ISM频段广泛使用的扩频技术 15
第三节 2.4GMz无线电波传输环境 17
第四节 对物理层电路框图的介绍 18
第五节 设计该电路要注意的地方 21
第六节 对无线收发电路的测试结果 22
第四章 数据链路层 24
第一节 数据链路层所完成的基本功能 24
一、 停止等待式机制 25
二、窗口机制 26
第二节 实现数据链路层功能所用的电路 27
结 论 29
参考文献 30 |
