摘要由于超声波指向性强，能量消耗缓慢，在介质中传播的距离较远，因而超声波经常用于距离的测量，如测距仪和物位测量仪等都可以通过超声波来实现。利用超声波进行测距往往比较迅速、方便、计算简单、易于做到实时控制，并且在测量精度方面能达到工业实用的要求，因此在倒车雷达系统中得到广泛的应用。本超声波测距系统电路采用模块化设计，由超声波发射接收模块、LCD液晶显示模块、温度检测模块、报警模块等组成。通过软件的编程使硬件功能通过单片机的综合处理得到实现。程序有主程序、发射子程序、接收子程序、显示子程序等。该设计抗干扰能力较好，实时性良好，误差可以达到mm级，可以有效地解决汽车倒车和对室内温度感知的问题。此课题采用STC89C52单片机为核心的低成本、高精度、微型化数字显示超声波测距仪的硬件电路和软件设计方法。通过单片机控制从而实现了倒车过程中汽车与障碍物之间的距离显示，当汽车与障碍物距离小于某个值时自动报警，本系统同时也拥有温度报警功能。通过按键设置最高最低温度值，当环境温度超过上限或者下限时，控制系统及时的报警等功能。关键词：单片机STC89C522，超声波传感器测量距离，温度传感器，倒车雷达AbstractBecauseofultrasonicdirectionalityisstrong,energyconsumptionisslow,inthemediumofcommunicationdistance,sooftenusedforthemeasurementofultrasonicdistance,suchasrangefinderandmateriallevelmeasurementinstrument,etccanallthroughtheultrasonictoachieve.Useofultrasonicdetectiontendtobequickly,convenientandsimplecalculation,easytodoreal-timecontrol,andinthemeasurementprecisioncanreachindustrypracticalrequirement,soinreverseradarsystemwidelyapplied.Theultrasonicrangingsystemadoptmodularizationdesigncircuit,byultrasoundreceivingmodule,LCDdisplaymodule,temperaturedetectionmodule,alarmmodule.Throughthesoftwareprogrammingmakehardwarefunctionthroughcomprehensivetreatmentofsinglechipachievedget.Programhasmainprogram,launchprocedure,receivingasubroutine,displayprocedure,etc.Thisdesignanti-interferenceabilityisgood,goodreal-timeperformance,errorcanachievemmlevel,caneffectivelysolvethecarbacktoindoortemperatureandtheproblemofperception.ThesystemthroughtheSTC89C52single-chipmicrocomputercontrolsoastorealizetheback-draftprocesscarsandobstaclesofthedistancebetweentheshows,whencarsandobstacledistancetoavaluelessthanwhentheautomaticalarm,thissystemalsohasthetemperaturealarmfunction.Throughthebuttonlowesthighesttemperature,whenenvironmenttemperaturemorethancaporlowerlimit,controlsystemtimelyalarmfunctions.Keywords：MCUSTC89C52，ultrasonicdistancesensor，temperaturetransmitter，ParkingDistanceControl目录摘要...............................................................................................................................................................ⅠAbstract.........................................................................................................................................................Ⅱ1.绪论.............................................................................................................................................................11.1课题背景及意义...................................................................................................................................11.2超声波简介...........................................................................................................................................11.3课题的主要内容...................................................................................................................................22.系统的...
