【正文】
指頻率高于20Hz的機(jī)械波。汽車擁有量在最近是一二十年里大幅增加,造成道路擁堵,交通事故頻發(fā),給人們的生命和財(cái)產(chǎn)安全帶來(lái)了巨大損失。對(duì)組成各系統(tǒng)電路的芯片進(jìn)行了介紹,并闡述了它們的工作原理。論文的內(nèi)容是基于AT89C51單片機(jī)結(jié)合于一體,設(shè)計(jì)出一種基于AT89C51單片機(jī)的倒車防撞報(bào)警系統(tǒng)。交通擁擠情況也日趨嚴(yán)重,撞車事件屢屢發(fā)生,造成了不可避免的人身傷亡和經(jīng)濟(jì)損失,針對(duì)這種情況,設(shè)計(jì)一種響應(yīng)快,可靠性高且較為經(jīng)濟(jì)的汽車防撞預(yù)警系統(tǒng)勢(shì)在必行,超聲波測(cè)距法是最常見(jiàn)的一種距離測(cè)距方法,本文介紹的就是利用超聲波測(cè)距法設(shè)計(jì)的一種倒車防撞報(bào)警系統(tǒng)。對(duì)于系統(tǒng)的一些主要參數(shù)進(jìn)行了討論,并且在介紹超聲波測(cè)距系統(tǒng)功能的基礎(chǔ)上,提出了系統(tǒng)的總體構(gòu)成,通過(guò)多種發(fā)射接收電路設(shè)計(jì)方案比較,得出了最佳設(shè)計(jì)方案,并對(duì)系統(tǒng)各個(gè)設(shè)計(jì)單元的原理進(jìn)行了介紹。關(guān)鍵詞:?jiǎn)纹瑱C(jī) 超聲波 AT89C51AbstractWith the development of society and economy of transportation industry is booming, the number of cars in the sharp rise. Traffic congestion has bee more and more serious, the crash occurred repeatedly, resulting from the inevitable casualty and economic loss, in view of this situation, design a kind of fast response, high reliability and more economy car collision avoidance warning system to be imperative, ultrasonic ranging method is the most mon type of distance measuring method, this paper describes the use of ultrasonic locating design a backdraft anticollision alarm system.The content of the thesis is based on the AT89C51 singlechip integration, design based on AT89C51 backdraft anticollision alarm system. The system uses a bination of hardware and software, the method of module, and multiuse characteristics. This paper summarizes the development and basic principle of ultrasonic detection, introduces the principle and characteristics of ultrasonic sensor. Some of the main parameters for the system were discussed, and introducing ultrasonic ranging system functions basis, the overall position of the system, through a variety of transmitting and receiving circuit design parison, the best design scheme, and various system design unit this paper introduces the principle of. On the position of the system circuit chip are introduced, and elaborated the principles of their work. This paper introduces the software structure of system, programmed to realize the function of the system. Finally, through the analysis of system error, an improved scheme is presented.Key words: single chip ultrasonic AT89C51目 錄1超聲檢測(cè)發(fā)展綜述 12 超聲波介紹 2 超聲波傳感器及其測(cè)距原理 2 什么是超聲波 2 壓電式超聲波傳感器簡(jiǎn)介 2 頻率特性 4 指向特性 53 單片機(jī)倒車防撞報(bào)警系統(tǒng)各組成單元方案設(shè)計(jì) 6 發(fā)射接收電路方案設(shè)計(jì) 6 系統(tǒng)顯示電路設(shè)計(jì) 7 系統(tǒng)報(bào)警電路設(shè)計(jì) 7 單片機(jī)復(fù)