Abstract
Sound frequencies above 20kHz is called Ultrasound, it belongs to the scope of
mechanical wave.Ultrasound can also follow the general mechanical wave
propagation in an elastic medium, as in the medium occurs at the interface reflection
and refraction, absorption of the medium into the medium occurred after attenuation.
Ultrasound can be used for distance measurement with these properties. With the
continuous improvement of technological level, ultrasonic distance measurement
techniques are widely used in daily work and life.
System design includes two parts, namely, hardware and software programs.
Hardware circuit includes a microcontroller circuit, transmitter circuit, receiver circuit,
display circuit and temperature compensation circuit, in addition to reset circuit and
communication circuit. AT89S52 microcontroller is the core of hardware which is
low cost,miniaturization,with LCD liquid crystal display and so on. The modular
design of the livelong circuit contains the signal transmission and reception,
temperature measurement, display, voice broadcast and other modules.The
microcontroller timer starts time when the probe launch ultrasound, after the original
ultrasound was reflected, ultrasound will be incepted by the probe,then
microcontroller stop working and get time. After sending the
temperature'measurement to the microcontroller, process of correction will revise the
speed.It can achieve the function of ultrasonic ranging by combining the anterior time
and speed. Main software program include preset subroutine, subroutines launch,
receive routine, display routines and other modules. It controls the microcontroller to
send and receive data, velocity correction on the ultrasonic at a certain temperature,
data displaying on the LCD.
Key Words ： AT89S52 ； Ultrasonic wave ； Ensor,Range Finder ； Tempearture
compensation；LCD
