摘要水流流速测量是水文工作的重要内容，在很多行业中都是一项很重要的工作。大到水利枢纽工程的测量，以及防洪抗旱等决策的制定，小到企业生产，家居生活。

本文分析了非接触式雷达多普勒流速测量系统的基本原理。根据系统的用途和性能要求，设计了雷达多普勒流速测量系统的整体方案，全面论述了系统的设计思想、硬件电路结构和软件的设计流程。47278

本设计系统以能够发送和接收电波的Stalker S3微波雷达传感器为信号处理核心，以低电压、高性能的AT89C51单片机为控制核心，同时也加入了电平转换电路、D/A转换电路和LCD显示电路。最后，通过软件代码的设计，系统可以实现传感器报文数据中当前流速的分离、D/A转换、LCD显示等功能。

背景，内容，结论

毕业论文关键词：微波雷达传感器；单片机；D/A转换；LCD显示

Abstract Rivers flow velocity measurement is the important content of the hydrologic work, which in many industry is very important, from Water Control Project measurement and flood control and drought relief decision-making to Enterprise production, household life. 

This article analyzes the basic principle of the radar Doppler velocity measurement system. According to the purpose of system and performance requirement, designs the overall solution of the radar Doppler velocity measurement system and comprehensively discusses the design idea, hardware structure and software designed process of the system. 

The sign processing core of the this design system is Stalker S3 microwave radar sensors that can send and receive waves and the control core of the system is AT89C51 microcontroller that is low voltage and high performance. In addition, the system also contains level converter circuit, D/A transformation circuit and the LCD display circuit. At last based on the design of the software code, the system can realize the function of the separation of the current velocity from the message data of the microwave radar sensors, D/A transformation and the LCD display.

Keywords: Microwave radar sensors; Microcontroller；Digital to Analog converter；LCD Display

 目  录

第一章 绪论 - 1 -

1.1 课题背景及其意义 - 1 -

1.2 国内外发展状况 - 2 -

1.3 本课题研究的主要内容 - 4 -

第二章 系统总体设计 - 6 -

2.1 基本原理 - 6 -

2.2 非接触微波雷达传感器的选择 - 7 -

2.3 系统总体设计方案 - 9 -

第三章 硬件电路设计 - 11 -

3.1 单片机的选择 - 11 -

3.2 D/A转换器 - 13 -

3.3 电平转换电路 - 17 -

3.4 LCD电路 - 20 -

3.5 电源模块 - 21 -

3.6 原理图的设计 - 22 -

3.7 PCB的设计 - 28 -

第四章 软件设计 - 30 -

4.1 MCS-51单片机开发环境 - 30 -

4.2 传感器报文数据（当前流速）的分离 - 32 -

4.3 D/A转换程序设计 - 36 -

4.4 LCD显示程序设计 - 37 -

结  论