【正文】 esonators to generator the internal structure as shown it has two piezoelectric chip and aresonance its two plus pulse signal the frequency equal to the intrinsicpiezoelectric oscillation frequency chip the chip will happen piezoelectric resonance andpromote the development of plate vibration resonance ultrasound is the two are not interelectrode voltage when the board received ultrasonic resonance itwill be for vibration suppression of piezoelectric chip the mechanical energy is convertedto electrical signals then it bees the ultrasonic traditional way to determine the moment of the echos arrival is based onthresholding the received signal with a fixed threshold is chosen well abovethe noise level whereas the moment of arrival of an echo is defined as the first moment theecho signal surpasses that intensity of an echo reflecting from an objectstrongly depends on the objects nature size and distance from the the timeinterval from the echos starting point to the moment when it surpasses the thresholdchanges with the intensity of the a consequence a considerable error may occurEven two echoes with different intensities arriving exactly at the same time will surpass thethreshold at different stronger one will surpass the threshold earlier than theweaker so it will be considered as belonging to a nearer principle of ultrasonic distance measurement Ultrasonic transmitter in a direction to launch ultrasound in the moment to launch thebeginning of time at the same time the spread of ultrasound in the air obstacles on his wayto return immediately the ultrasonic reflected wave received by the receiver immediatelystop the in the air as the propagation velocity of 340m / s according tothe timer records the time t we can calculate the distance between the launch distancebarrier s that is: s 340t / Ranging System for the Second Circuit Design ‐8‐ 畢業(yè)設計（論文）英文翻譯 System is characterized by singlechip microputer to control the use of ultrasonictransmitter and ultrasonic receiver since the launch from time to time singlechip selectionof 8751 economictouse and the chip has 4K of ROM to facilitate diagram shown in Figure 1 circuit principle diagram ‐9‐ 畢業(yè)設計（論文） 40 kHz ultrasonic pulse generated with the launch Ranging system using the ultrasonic sensor of piezoelectric ceramic sensors UCM40its operating voltage of the pulse signal is 40kHz which by the singlechip implementationof the following procedures to : mov 14h 12h ultrasonic firing continued 200mshere: cpl output 40kHz square wave nop nop nop djnz 14h here ret Ranging in front of singlechip termination circuit input port single chipimplementation of the above procedure the port in a 40kHz pulse output signal afteramplification transistor T the drive to launch the first ultrasonic UCM40T issued 40kHzultrasonic pulse and the continued launch of the right and the left side ofthe circuit respectively then input port and the working principle and circuit infront of the same Reception and processing of ultrasonic Used to receive the first launch of the first pair UCM40R the ultrasonic pulsemodulation signal into an alternating voltage the opamp amplification IC1A and afterpolarization IC1B to is locked loop with audio decoder chip LM567 internalvoltagecontrolled oscillator center frequency of f0 1/ capacitor C4 determinetheir target in the launch of the carrier frequency on theLM567 input signal is greater than 25mV the output from the high jump 8 feet into alowlevel as interrupt request signals to the singlechip in front of singlechip termination circuit output port INT0 interrupt thehighest priority right or left location of the output circuit with output gate IC3A accessINT1 port singlechip while singlechip and received input IC3A interrupted ‐10‐ 畢業(yè)設計（論文）英文翻譯by the process to identify the source of inquiry to deal with interrupt priority level for thefirst left right of the source code is as follows:receive1: push psw push acc clr ex1 related external interrupt 1 jnb right pin to 0 ranging from right to interrupt serviceroutine circuit jnb left pin to 0 to the left ranging circuit interruptservice routinereturn: SETB EX1 open external interrupt 1 pop acc pop psw retiright:...right location entrance circuit interrupt service routine Ajmp Returnleft:...left Ranging entrance circuit interrupt service routine Ajmp The calculation of ultrasonic propagation time When you start firing at the same time start the singlechip circuitry within the timerT0 the use of timer counting function records the time and the launch of ultrasonicreflected wave received you receive the ultrasonic reflected wave the receivercircuit outputs a negative jump in the end of INT0 or INT1 interrupt request generates asignal singlechip microputer in response to external interrupt request theimplementation of the external interrupt service subroutine read the time differencecalculating the of its source code is as follows:RECEIVE0: PUSH PSW PUSH ACC CLR EX0 related external interrupt 0.第三篇：超聲波測距報警器文獻綜述超聲波測距報警器的設計與實現(xiàn)超聲波測距報警器的設計與實現(xiàn)摘要：本系統(tǒng)采用了單片機最小系統(tǒng)、超聲波模塊、顯示模塊、報警模塊等。因此，它不僅可用于移動機器人，還可用在其它檢測系統(tǒng)中。結論 對所要求測量范圍 30cm200cm 內(nèi)的平面物體做了多次測量發(fā)現(xiàn)，且重復性好。主程序完成初始化工作、各路超聲波發(fā)射和接收順序的控制。第六步：通過公式計算距離 y。測量過零時間與回波的振幅。根據(jù)第二部的數(shù)據(jù)設定時間窗。第四步：設置回波放大器的所得來規(guī)格輸出，假定是 3 伏。第二步：根據(jù)公式改變回波放大器的獲得量直到回撥被檢測到。其部分源程序如下：RECEIVE0： PUSH PSW PUSH ACC CLR EX0 ； 關外部中斷 0 MOV R7 TH0 ； 讀取時間值 MOV R6 TL0 CLR C MOV A R6 SUBB A 0BBH； 計算時間差 MOV 31H A ； 存儲結果 MOV A R7 SUBB A 3CH MOV 30H A SETB EX0 ； 開外部中斷 0 POP ACC ‐4‐ 畢業(yè)設計（論文）英文翻譯 POP PSW RETI對于一個平坦的目標，距離測量包括兩個階段:粗糙的測量和精細測量。部分源程序如下：receive1：push psw push acc clr ex1； 關外部中斷 1 jnb ； 引腳為 0轉(zhuǎn)至右測距電路中斷服務程序 ‐3‐ 畢業(yè)設計（論文）英文翻譯 jnb ； 引腳為 0轉(zhuǎn)至左測距電路中斷服務程序return： SETB EX1； 開外部中斷 1 pop acc pop psw retiright：...； 右測距電路中斷服務程序入口 ajmp returnleft：...； 左測距電路中斷服務程序入口 ajmp 計算超聲波傳播時間 在啟動發(fā)射電路的同時啟動單片機內(nèi)部的定時器 T0，利用定時器的計數(shù)功能記錄超聲波發(fā)射的時間和收到反射波的時間。是帶有鎖 定環(huán)的音頻譯碼集成塊LM567，內(nèi)部的壓控振蕩器的中心頻率 f01/，電容 C4 決定其鎖定帶寬。右側(cè)和左側(cè)測 距電路的輸入端分別接 和 端口，工作原理與前方測距電路相同。‐1‐畢業(yè)設計（論文）英文翻譯 圖 1 電路原理圖 ‐2‐ 畢業(yè)設計（論文） 40