摘要本文主要对毫米波无线数据传输编解码器设计方法与过程进行了阐述,系统以51系列单片机为核心。此次课题设计使用的是ATMEL公司的AT89S51和AT89S2051,完成数据编解码器设计,以实现12位数据的毫米波无线传输,系统主要有数据采集、编码发送和数据接收解码三部分组成。设计过程包括涉及基于Protel99se软件平台的硬件电路设计和基于Keil高级程序语言平台的软件设计。在利用单片机和无线数据传模块进行无线数据通信时,通常的办法是通过单片机的串行I/O口来完成数据的串行通信。然而此方法存在许多不足之处,如差错检测能力差、帧格式不灵活等。针对高速通信的场合,提出了一种通过单片机和无线数据传模块以软件方式实现对传输数据编码、解码的原理与方法(通过控制计数器延时对数据进行编码,通过设定延时判断电平的方式对数据进行解码)。此外还介绍了一种改进的编解码方式即“曼彻斯特编解码”。数据的编码采用了曼彻斯特编码格式,每帧数据包括同步头、有效数据位和冗余校验位这三部分。解码包括同步头和数据位的判定及循环冗余校验。在数据位的判定中提出了用软件实现“样本取多”的判定方法。该判定方法不但可以提高采样的准确度,而且还具有一定的滤波功能。实验表明,该套系统能有效运作,可以实现在复杂环境下快速稳定地进行数据通信的设计目的,应用前景广阔。64173
毕业论文关键词 无线数据通信;单片机;编码/解码;毫米波;串行通信
毕业设计说明书(论文)外文摘要
Title Design of millimeter wave wireless data transmission codec
Abstract This paper mainly discusses the design and implementation of millimeter wave wireless data transmission codec. The system based on AT51 series microcontroller is designed in this paper. AT's AT89S51 and AT89S2051 is used in this project to achieve the purpose which is 12 bits of millimeter wave wireless communication data to be transmitted. The system is composed of data acquisition, encoding and decoding. The design process including hardware circuit design based on Protel99se and software design using advanced programming language platform KeilC. During the part of software design, a simple way to code is introduced. Encode the data by controlling a counter delay and decode the data by judging whether the electrical level has changed during a set delay as well. Furthermore, Manchester code was used in data coding format. Each frame of data included three parts of synchronous head, valid data bits and redundancy check. Decoding included synchronous head and data bits determination and cyclic redundancy check. Experiments shows that, the system can operate effectively even in complex environment will have a broad prospect in application.
Keywords wireless data communications; MCU; encode; decode; millimeter wave; serial communication
1 引言 3
2总体设计 4
2.1毫米波通信结构 4
3 系统硬件设计 5
3.1硬件电路框图 5
3.2发送模块AT89S51 6
3.2.1.单片机芯片选择 7
3.2.2 输入/输出(I/0端口)结构 9
3.2.3 XTAL口外接晶振结构 10
3.2.4 复位电路结构