Distance measurement method and device using ultrasonic waves

• US 20060247526A1
• Filed: 07/29/2004
• Published: 11/02/2006
• Est. Priority Date: 07/29/2003
• Status: Abandoned Application

• Current Assignee: KT Corporation
• Original Assignee: KT Corporation
• Inventors: Lee, Dong Hwal, Kang, Young Shin, An, Heui Tay
• Application Number:
  US10/566,286
• Publication Number:
  US 20060247526A1
• Time in Patent Office: Days
• US Class Current: 600/438
• CPC Class Codes: G01S 15/102 using transmission of pulses having some particular characteristics

Abstract

The present invention provides a distance measurement method and device using ultrasonic sufficiently amplifying a received ultrasonic wave signal and separating a specific frequency from an ultrasonic wave signal mixed with an unnecessary signal to extract an arrival signal of a first pulse. It is thus possible to calculate a distance of an object safely.

Claims

1. A distance measurement method using ultrasonic, comprising the steps of:

transmitting an ultrasonic pulse having specific frequencies to each object;

receiving the ultrasonic pulse that is reflected from the object or directly transmitted; and

extracting a specific frequency of the received ultrasonic wave pulse to find an arrival time of a first pulse and converting the time into a distance.

2. The distance measurement method as claimed in claim 1, wherein the step of finding the arrival time and converting the time into the distance further includes the step of separating a specific frequency of the ultrasonic and converting an arrival time of an ultrasonic that is received for the first time among the separated ultrasonic into the distance, in a state where the waveform is mixed with noise having different frequency properties from the specific frequency of the transmitted ultrasonic.

3. The distance measurement method as claimed in claim 1, wherein in the step of converting the time into the distance, the extraction of the specific frequency from the received ultrasonic further comprises the steps of:

amplifying the received ultrasonic to generate an amplified signal;

weakening a signal of an unnecessary frequency among the amplified signal through an analog filter circuit to generate a filtered signal;

amplifying the filtered signal again to generated a re-amplified signal;

converting the re-amplified signal into a digital signal; and

extracting a specific frequency from the converted digital signal through a digital signal processing.

4. The distance measurement method as claimed in claim 3, further comprising the step of specifying a distance range to be excluded when measuring a distance of the object, such that a distance exceeding the specified distance range is measured.

5. The distance measurement method as claimed in claim 1, wherein the step of receiving the ultrasonic reflected from the object while the object is moving comprises changing a received frequency depending on variation of the frequency of the transmitted ultrasonic.

6. A distance measurement method using ultrasonic, comprising the steps of:

installing a first receiver for receiving an ultrasonic at a known position;

installing a second receiver for receiving an ultrasonic at an object to be measured;

transmitting an ultrasonic having a specific frequency from a location where a distance from the object will be measured, to the first and second receivers;

extracting specific frequencies of the ultrasonic received from the first and second receivers to find an arrival time of a first signal and converting the time into a distance;

transmitting error information related to a difference between the distance received by the first receiver and the known distance to the second receiver; and

allowing the second receiver to correct the velocity of sound using the error information.

7. A distance measurement device using ultrasonic, comprising:

a transmitter for generating an ultrasonic having a specific frequency;

a sensor for detecting the ultrasonic reflected from an object;

an amplifier for amplifying the ultrasonic detected by the sensor;

an analog filter for selectively attenuating other frequencies except for a specific frequency from the ultrasonic amplified by the amplifier;

a secondary amplifier for amplifying an analog signal selected through the analog filter;

an A/D converter for converting the amplified analog signal to a digital data;

a memory for storing the digital data therein;

a digital signal processor for processing the digital data stored in the memory;

an output unit for displaying results processed in the digital signal processor;

a numerical input unit for informing the digital signal processor of a processing condition; and

a communication unit for connecting the digital signal processor and an external apparatus to each other so that the digital signal processor and the external apparatus can exchange information,

wherein a transmission time of a first signal among the received ultrasonic and a delayed time of an arrival time of the first signal calculated in the digital signal processor are measured.