摘要目前，我国大多数汽车倒车雷达采用超声波测距方式测量障碍汽车与障碍物的距离，使用单片机对超声波探头进行控制，使用数码管显示汽车尾部到障碍物的距离然后使用蜂鸣器进行声音报警。它只能显示车到障碍物的距离，无法显示车后方的直观影像，司机无法看到地坑和低矮的障碍物。本课题所研究的内容是使用DSP芯片作为视频采集显示模块的主控芯片，用单片机做为超声波测距模块的主控芯片的倒车雷达可视装置。本文按照系统要求的功能设计了硬件的框架，并通过各种资料查找要实现这些功能所需要掌握的方法及原理，然后做出了硬件的原理图并用C语言编写了系统的软件部分。系统通过 DSP数字处理芯片控制 OV7740 摄像头进行图像采集，使用STC89C52作为超声波测距的主控芯片，并分别通过彩色液晶屏和显示屏把汽车后的障碍物信息传递给驾驶员，然后通过和设定的报警距离进行比较若小于设定的报警距离则开启蜂鸣器报警。本文然后根据理论分析和需求进行硬件和软件设计。在硬件方面给出了芯片的选型，设计时用到的理论，并画出了电路的原理图；软件方面通过KeilC51C语言开发软件编写了超声波测距源程序，并做出了视频采集显示、超声波测距程序设计方框图。84464

毕业论文关键词：超声波传感器，DSP芯片，STC89C52单片机

Abstract At present, most of the car reversing radar in our country use ultrasonic distance measurement method to measure the distance between the obstacle and the obstacle, Control of ultrasonic probe by using single chip microcomputer, using LED digital tube to display the distance also has the sound and light alarm function。It can only show the distance between the vehicle and the obstacle, could not display the rear visual image, driver cannot see the pit and low obstacles。The content of this research is to use DSP chip as the video capture module。STC89C52 single chip microcomputer as the ultrasonic ranging module reversing radar visual system。Firstly, according to the system requirement, this paper analyzes the feasibility of the system in theory,the feasibility of the implementation of the system is analyzed theoretically。System through the DSP digital processing chip to control the OV7740 camera image acquisition,using STC89C52 as the main control chip of ultrasonic distance measurement,and through the color LCD screen and 1602LCD screen to the car after the obstacle information to the driver,And according to the set to display the distance of the threshold and the threshold of the alarm to determine the range of display and alarm。In this paper, according to the theoretical analysis and demand for hardware and software design。Hardware, given the hardware design schematic diagram of interface circuit; software by Keil C51 microcontroller C language to develop the system compiled ranging source, given the video acquisition and display, ultrasonic ranging program design block diagram。

Keywords：ultrasonic sensor，DSP，STC89C52 microcomputer

目录

第一章 绪论 1

1。1选题的目的和意义 1

1。2课题研究背景 1

1。3研究现状 1

1。4研究内容 2

1。5论文的结构 3

第二章 系统总体结构设计 4

2。1 系统的基本功能 4

2。2系统的总体结构 4

2。3测距传感器的选择 5

2。3。1激光测距