ULTRASONIC DISTANCE MEASURING DEVICE, ULTRASONIC DISTANCE MEASURING METHOD AND ULTRASONIC DISTANCE MEASURING PROGRAM

摘要

PROBLEM TO BE SOLVED: To provide an ultrasonic distance measuring device capable of accurately measuring a distance to a measuring object using a reflection wave from the object, even in an environment where a direct wave or a proximity reflection wave exists.;SOLUTION: An ultrasonic distance measuring device 1 comprises: a transmitter 15 for converting transmission signals B modulated with a specific code A into ultrasonic waves and transmitting them; receivers 21, 25 for receiving reflection waves generated when an object reflects ultrasonic waves, converting the reflection waves into reception signals C, and demodulating them; a correlation value calculator 31 for calculating correlation values between demodulated reception signals D and the specific code A; a peak detector 32 for detecting, from among calculated correlation values, a specific peak whose magnitude is larger than a predetermined value and corresponding to which a distance to the object is smaller than a predetermined value; a cancel signal generator for generating a cancel signal from a transmission signal or a reception signal; and a subtractor 41 for subtracting a cancel signal from a reception signal so as to reduce the magnitude of the specific peak.;SELECTED DRAWING: Figure 1;COPYRIGHT: (C)2018,JPO&INPIT