目录
第一章 绪论 ......................................................................................................................................................1
1.1 课题设计的目的及意义 .....................................................................................................................1
1.2.2 超声波测距原理框图 .............................................................................................................2
1.2.3 超声波测距 ............................................................................................................................2
第二章 超声波的发展及测距原理 ..................................................................................................................3
2.1 超声波的发展与运用 .........................................................................................................................3
2.2 超声波测距原理 .................................................................................................................................3
2.3 超声波测距在汽车上的运用 ............................................................................................................5
2.4 超声波传感器的介绍 ........................................................................................................................6
2.4.1 超声波传感器介绍 ................................................................................................................6
2.4.2 超声波传感器的特性 ............................................................................................................7
第三章 系统硬件设计 ....................................................................................................................................9
3.1 系统设计的要求 ................................................................................................................................9
3.2 系统整体设计方案 ..........................................................................................................................10
3.3 单片机系统介绍 ..............................................................................................................................10
3.3.1 AT89C51 单片机介绍 ...........................................................................................................10
3.3.3 单片机的时钟电路 ...............................................................................................................16
3.3.4 单片机的电源电路 ..............................................................................................................17
3.4 超声波发射电路 ..............................................................................................................................25
3.5 超声波接收电路 ..............................................................................................................................26
3.5.1 CX20106A 集成电路介绍 .....................................................................................................26
3.5.2 超声波接收电路 ...................................................................................................................28
3.6 距离显示电路 ..................................................................................................................................29
3.7 报警电路 ..........................................................................................................................................30
3.7.1 音频集成功放 LM386 简介 ..................................................................................................30
第四章 系统软件设计 ....................................................................................................................................32
结论..................................................................................................................................................................35
致谢..................................................................................................................................................................38
参考文献..........................................................................................................................................................39
附录..................................................................................................................................................................40
附录一：系统电路图 ..............................................................................................................................40
附录二：主要元器件清单 ......................................................................................................................41
附录三：源程序 ......................................................................................................................................42
