METHOD AND SYSTEM FOR RECOGNIZING LOCATION BY USING SOUND SOURCES WITH DIFFERENT FREQUENCIES

• US 20090154294A1
• Filed: 09/19/2008
• Published: 06/18/2009
• Est. Priority Date: 12/17/2007
• Status: Active Grant

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: Kim, Hong-Kee, Kim, Jong-Sung, Jeong, Hyuk, Son, Wook-Ho
• Granted Patent: US 7,916,577 B2
• Time in Patent Office: Days
• US Class Current: 367/128
• CPC Class Codes: G01S 11/16 using difference in transit time between electrical and acoustic signals
• CPC Class Codes: G01S 5/30 Determining absolute distances from a plurality of spaced points of known location

Abstract

Provided are a method and a system for recognizing a location to control the location of a moving object by installing an ultrasonic satellite transmitting an ultrasonic signal. The method includes generating a synchronizing signal at a plurality of the ultrasonic satellites. The ultrasonic satellites simultaneously transmit the ultrasonic signals respectively having different frequency from each other. A receiver of the moving object receiving the ultrasonic signal measures a distance between the receiver of the moving object and each ultrasonic satellite by classifying a frequency of the ultrasonic signal, and calculates a current location of the moving object by using the measured distance. The system includes ultrasonic satellites for transmitting ultrasonic signals, a moving object for recognizing a current location by receiving the ultrasonic signals from the ultrasonic satellites, a reference time broadcasting device for providing a synchronizing signal to the ultrasonic satellites and the moving object in operation, and a server for providing coordinates of the ultrasonic satellites to the moving object.

Claims

1. A method for recognizing a location to control the location of a moving object by installing an ultrasonic satellite transmitting an ultrasonic signal, the method comprising:

generating a synchronizing signal at a plurality of the ultrasonic satellites;

simultaneously transmitting, at the ultrasonic satellites, the ultrasonic signals respectively comprising different frequency from each other;

measuring, at a receiver of the moving object receiving the ultrasonic signal, a distance between the receiver of the moving object and each ultrasonic satellite by classifying a frequency of the ultrasonic signal; and

calculating a current location of the moving object by using the measured distance.

2. The method of claim 1, further comprising:

endowing each of the plurality of the ultrasonic satellites with a unique serial number;

transmitting, at the ultrasonic satellites, the unique serial number, a location information and a frequency used in each of the ultrasonic satellites, to the moving object; and

storing/managing the unique serial number, the location information and the frequency in the receiver of the moving object.

3. The method of claim 1, further comprising disposing three ultrasonic satellites coplanarly on a ceiling or a floor of a space in which the moving object is able to move.

4. The method of claim 1, wherein the measuring of the distance comprises:

receiving the ultrasonic signal comprising different frequency transmitted from the ultrasonic satellite immediately or at a predetermined time after a reception of the synchronizing signal;

obtaining a time interval between a simultaneous time or a predetermined lapsed time after the reception of the synchronizing signal and a time of the reception of the ultrasonic signal; and

calculating the distance from each of the ultrasonic satellites by multiplying the time interval by the velocity of sound.

5. The method of claim 1, wherein the measuring of the distance comprises:

comprising information on a time when the ultrasonic signal is transmitted from each of the ultrasonic satellites in the transmitted ultrasonic signal;

obtaining a time interval between a time recorded in the information comprised in the received ultrasonic signal and a time when the receiver receives the ultrasonic signal actually; and

calculating the distance from each of the ultrasonic satellites by multiplying the time interval by the velocity of sound.

6. A location determination receiver for recognizing a location of a moving object, comprising:

an ultrasonic antenna;

a receiving unit capable of simultaneously processing three or more ultrasonic signals;

a operation unit for calculating a distance from each of ultrasonic satellites transmitting each of the ultrasonic signals by using a reception of each of the ultrasonic signals; and

a location determining unit for calculating a current location of the receiver by using the distance from each of ultrasonic satellites.

7. The location determination receiver of claim 6, wherein the receiving unit receives frequency components of all the ultrasonic signals to extract each of the frequency components from the ultrasonic signals.

8. The location determination receiver of claim 6, wherein the receiving unit comprising a plurality of receiving ends for receiving ultrasonic signals respectively having a specific frequency.

9. The location determination receiver of claim 6, further comprising a timer.

10. A system for recognizing a location of a moving object, comprising:

a plurality of ultrasonic transmitters for transmitting an ultrasonic signal comprising different frequency respectively;

a reference signal broadcasting device for supplying a synchronizing signal to each of the ultrasonic transmitters;

a ultrasonic receiver for determining its own three-dimensional location by receiving the ultrasonic signals from the ultrasonic transmitters;

a server for providing location coordinates of the plurality of the ultrasonic transmitters; and

wherein the ultrasonic transmitters simultaneously transmit the ultrasonic signals in accordance with the control of a controller.

11. The system of claim 10, wherein the number of the ultrasonic transmitters are three or more when the ultrasonic transmitters are coplanarly disposed within a space in which the moving object is able to move, and are four or more when the ultrasonic transmitters are non-coplanarly disposed.