Mobile device and method for processing an acoustic signal

• US 8,928,630 B2
• Filed: 07/02/2010
• Issued: 01/06/2015
• Est. Priority Date: 10/09/2009
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Lee, Ho-Sub
• Primary Examiner(s): Lee, Gene W
• Application Number:
  US12/829,646
• Publication Number:
  US 20110084940A1
• Time in Patent Office: 1,649 Days
• Field of Search: 345156-184, 178 1801- 1811, 178 1901- 1907, 178 2001- 2004
• US Class Current: 345/177
• CPC Class Codes: G06F 3/0416 Control or interface arrangements specially adapted for digitisers
• CPC Class Codes: G06F 3/043 using propagating acoustic waves
• CPC Class Codes: G06F 3/04883 for inputting data by handwriting, e.g. gesture or text

Abstract

A mobile device and method for processing an acoustic signal are provided. The mobile device may calculate a position of an inputted touch and recognize a character from the calculated position. The mobile device may perform a function corresponding to the recognized character, or display the position of the touch.

Claims

1. A mobile device for processing an acoustic signal, the device comprising:

a sensing unit configured to sense an acoustic signal based on a touch inputted on a surface of the mobile device;

an acoustic signal processing unit configured to perform signal processing on the sensed acoustic signal and determine an actual propagation speed of the sensed acoustic signal using a vibration unit;

an acoustic signal position determining unit configured to divide the signal-processed acoustic signal into segments of the signal corresponding to different periods of time, and apply a multilateration comprising a hyperbolic positioning method to each of the divided segments to calculate consecutive coordinates with respect to the position of the inputted touch; and

a character recognition unit configured to recognize a character from the consecutive coordinates.

2. The mobile device of claim 1, wherein the sensing unit comprises at least one of:

a noise sensor, a vibration sensor, and an ultrasonic sensor.

3. The mobile device of claim 1, wherein the acoustic signal processing unit is further configured to process the acoustic signal by performing at least one of:

amplifying and filtering the sensed acoustic signal.

4. The mobile device of claim 1, wherein the acoustic signal processing unit is further configured to process the acoustic signal to convert the sensed analog acoustic signal to a digital acoustic signal by performing at least one of:

a sampling operation, a quantization operation, and an encoding operation.

5. The mobile device of claim 1, wherein the character recognition unit is further configured to recognize a character based on an input of consecutive coordinates of the calculated position.

6. The mobile device of claim 1, further comprising:

a user configuration unit configured to receive, from a user, a designation for a function to be performed in association with the recognized character; and

a function execution unit configured to perform a function corresponding to the recognized character.

7. The mobile device of claim 1, wherein:

the sensing unit comprises a plurality of acoustic sensor pairs; and

the acoustic signal position determining unit is further configured to;

measure a difference in time from when the acoustic signal reaches each of the plurality of acoustic sensor pairs; and

calculate coordinates of the position using the measured difference in times.

8. The mobile device of claim 7, wherein the acoustic signal position determining unit is further configured to calculate the coordinates of the position inputted by the touch using Equations 1 and 2,

√

{square root over ((X−

X₁)²+(y−

y₁)²)}{square root over ((X−

X₁)²+(y−

y₁)²)}−

√

{square root over ((x−

x₃)²+(y−

y₃)²)}{square root over ((x−

x₃)²+(y−

y₃)²)}=vΔ

t_1,3 

 

[Equation 1]

and

√

{square root over ((X−

X₂)²+(y−

Y₂)²)}{square root over ((X−

X₂)²+(y−

Y₂)²)}−

√

{square root over ((X−

X₄)²+(y−

y₄)²)}{square root over ((X−

X₄)²+(y−

y₄)²)}=vΔ

t_2,4 

 

[Equation 2]

where x and y denote coordinates of the position of the inputted touch, and (x₁,y₁), (x₂,y₂), (x₃,y₃), and (x₄,y₄) denote coordinates of the locations of the plurality of acoustic sensor pairs.

9. A mobile device for processing an acoustic signal, the mobile device comprising:

a sensing unit configured to sense an acoustic signal based on a touch event with respect to an object that is approximately in contact with the mobile device;

an acoustic signal processing unit configured to perform signal processing on the sensed acoustic signal and determine an actual propagation speed of the sensed acoustic signal using a vibration unit;

an acoustic signal position determining unit configured to divide the signal-processed acoustic signal into segments of the signal corresponding to different periods of time, and apply a multilateration comprising a hyperbolic positioning method to each of the divided segments to calculate consecutive coordinates with respect to the position of the inputted touch; and

a shape recognition unit configured to recognize the consecutive coordinates as a shape.

10. The mobile device of claim 9, further comprising:

the vibration unit is configured to generate a vibration signal based on the sensed acoustic signal,

wherein the acoustic signal processing unit is further configured to measure the actual propagation speed of the sensed acoustic signal based on the distance between the sensing unit and the vibration unit and the time it takes for the vibration signal to be sensed by the sensing unit.

11. The mobile device of claim 9, further comprising a display unit configured to display the recognized shape in a symmetrical manner.

12. A method of processing an acoustic signal, the method comprising:

sensing an acoustic signal based on a touch inputted on a surface of a mobile device or an object that is approximately in contact with the mobile device;

signal processing the sensed acoustic signal;

determining an actual propagation speed of the sensed acoustic signal using a vibration unit;

dividing the signal-processed acoustic signal into segments of the signal corresponding to different periods of time;

calculating consecutive coordinates of the position of the inputted touch by applying a multilateration comprising a hyperbolic positioning method to each of the divided segments; and

executing a function based on the consecutive coordinates.

13. The method of claim 12, wherein the sensing comprises sensing the acoustic signal based on the touch inputted on the object that is approximately in contact with the mobile device.

14. The method of claim 12, wherein:

the signal processing comprises at least one of;

amplifying and filtering the sensed acoustic signal; and

the signal processing comprises at least one of;

a sampling operation, a quantization operation, and an encoding operation to convert the sensed analog acoustic signal into a digital acoustic signal.

15. The method of claim 12, wherein the calculating comprises calculating the position using a multilateration comprising a position calculation algorithm, based on the time it takes for the acoustic signal to reach an acoustic sensor that includes at least one of:

a noise sensor, a vibration sensor, and an ultrasonic sensor.

16. The method of claim 12, wherein the calculating comprises:

measuring a difference in time from when the acoustic signal reaches each of a plurality of acoustic sensor pairs for sensing the acoustic signal; and

calculating coordinates of the position by applying the measured difference in times to Equations 1 and 2,

√

{square root over ((x−

x₁)²+(y−

y₁)²)}{square root over ((x−

x₁)²+(y−

y₁)²)}−

√

{square root over ((x−

x₃)²+(y−

y₃)²)}{square root over ((x−

x₃)²+(y−

y₃)²)}=vΔ

t_1,3 

 

[Equation 1]

and

√

{square root over ((x−

x₂)²+(y−

Y₂)²)}{square root over ((x−

x₂)²+(y−

Y₂)²)}−

√

{square root over ((X−

X₄)²+(y−

y₄)²)}{square root over ((X−

X₄)²+(y−

y₄)²)}=vΔ

t_2,4 

 

[Equation 2]

where x and y denote coordinates of the position of the inputted touch, and (x₁,y₁), (x₂,y₂), (x₃,y₃), and (x₄,y₄) denote coordinates of the position of the plurality of acoustic sensor pairs.

17. The method of claim 12, further comprising:

storing, in a storing unit, a character corresponding to the function to be performed,

wherein the executing comprises;

recognizing, as a character, a consecutive input with respect to coordinates of the calculated position; and

executing the function based on the recognized character stored in the storing unit.

18. The method of claim 12, further comprising:

recognizing the calculated position as a continuous shape; and

displaying, on a screen, the recognized shape.

19. A non-transitory computer-readable storage medium storing a program for controlling a computer to execute a method, the method comprising:

sensing an acoustic signal based on a touch inputted on a surface of a mobile device or an object that is approximately in contact with the mobile device;

signal processing the sensed acoustic signal;

determining an actual propagation speed of the sensed acoustic signal using a vibration unit;

dividing the signal-processed acoustic signal into segments of the signal corresponding to different periods of time;

calculating consecutive coordinates of the position of the inputted touch by applying a multilateration comprising a hyperbolic positioning method to each of the divided segments; and

executing a function based on the consecutive coordinates.