Abstract:
A system and method for controlling a digital TV, the system including the DTV; and a 3D pointing device. The DTV includes a receiver to receive control signals from the 3D pointing device; and a control unit to select one of a plurality of functions provided by the DTV in response to a selection signal received from the 3D pointing device, each function having a corresponding execution profile, and execute the selected function in accordance with the corresponding execution profile and a motion parameter sensed by the 3D pointing device including a direction of movement and one of a distance and velocity corresponding to the direction of movement. The 3D pointing device includes a transmitter to transmit the control signals and motion parameter; and a sensor to sense within the 3D pointing device the motion of the 3D pointing device and generate the corresponding motion parameter.

Description:
CROSS REFERENCES TO RELATED APPLICATIONS 
     This nonprovisional application claims priorities under 35 U.S.C. §119(a) on Patent Application No. 10-2008-0051930 filed in Republic of Korea on Jun. 3, 2008 and Application No. 10-2008-0078849 filed in Republic of Korea on Aug. 12, 2008 the entire contents of which are hereby incorporated by references. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This document relates to digital television (DTV) that is able to receive signals from a three-dimensional (3D) pointing device, and more particularly, to DTV that is able to receive signals from a 3D pointing device, which can vary an execution speed according to the degree of motion of the 3D pointing device, in executing functions of DTV in response to the motion of the 3D pointing device, a method of executing the functions of DTV by employing the 3D pointing device, and a method of adjusting the audio properties of DTV by employing the 3D pointing device. 
     2. Discussion of the Related Art 
     Currently, active research has been done on a 3D pointing device or a 3D remote controller employing a gyro sensor or an accelerometer. However, despite that electronic devices, being controlled by the 3D pointing device, are quite numerous, development on applications regarding the electronic devices is insufficient. 
     In recent years, DTV has become providing a variety of functions such as reception of analog or digital broadcasting, reception of electronic program guide (EPG), bi-directional communication, and Internet access. DTV also has become responsible for the functions of a server in home network environment or ubiquitous environment. 
     As DTV has been able to perform a lot of the functions, items that should be controlled by a user have increased and become complicated. Thus, there is a problem that a remote controller of an existing infrared communication method cannot control the complicated functions efficiently. 
     To solve the problem, the remote controller of an existing infrared communication method can be replaced with the 3D pointing device. However, research on how DTV can be controlled efficiently using the 3D pointing device has not been done sufficiently. In particular, there is an urgent need for development where the device characteristics of the 3D pointing device, being able to sense 3D motion, can be efficiently employed in DTV. 
     SUMMARY OF THE INVENTION 
     An aspect of this document is to provide DTV that is able to receive signals from a 3D pointing device, which can vary an execution speed of functions provided from the DTV according to the degree of motion of the 3D pointing device, a method of executing the functions of DTV by employing the 3D pointing device, and a method of adjusting the audio properties of DTV by employing the 3D pointing device. 
     Another aspect of this document is to provide DTV that is able to receive signals from a 3D pointing device, which can sense 3D motion and whose device characteristics can be used to control DTV effectively, a method of executing the functions of DTV by employing the 3D pointing device, and a method of adjusting the audio properties of DTV by employing the 3D pointing device. 
     In an aspect of this document, there is a method of executing functions of DTV by employing a 3D pointing device, wherein the DTV can receive signals from the 3D pointing device that recognizes 3D motion, the method comprising selecting a function provided by the DTV, sensing motion of the 3D pointing device, and executing the selected function, wherein an execution speed of the selected function is controlled according to a degree of the sensed motion. 
     The method may further comprise entering a recognition mode for recognizing the motion of the 3D pointing device according to a user&#39;s manipulation on the 3D pointing device, before the motion of the 3D pointing device is sensed. 
     The execution of the selected function may comprise controlling the execution speed in consideration of at least one of the selected function itself, a distance of the sensed motion, and a speed of the sensed motion. 
     The execution of the selected function may comprise controlling the execution speed in consideration of a current value regarding the selected function. 
     The execution of the selected function may comprise controlling the execution speed in consideration of a direction of the sensed motion, wherein an increment and decrement of a value regarding the selected function may be previously set according to the direction of the sensed motion. 
     The selected function may comprise a function for controlling an output state of information. Here, the selected function may comprise a volume control function of audio information or a picture quality control function of video information. 
     The execution speed can be set by a user. 
     In another aspect of this document, there is a method of executing functions of DTV by employing a 3D pointing device, wherein the DTV can receive signals from the 3D pointing device that recognizes 3D motion, the method comprising executing a first function at a first response speed with respect to motion of the 3D pointing device, selecting a second function different from the first function, and executing the second function at a second response speed different from the first response speed with respect to the motion of the 3D pointing device. 
     The method may further comprise entering a recognition mode for recognizing the motion of the 3D pointing device according to a user&#39;s manipulation on the 3D pointing device. 
     The first and second response speeds may have different values although at least one of a distance of the motion of the 3D pointing device, a speed of the motion of the 3D pointing device, and a direction of the motion of the 3D pointing device is identical. 
     The first and second response speeds may be decided in consideration of at least one of a corresponding function itself and a current value regarding the corresponding function. 
     The first and second response speeds can be set by a user. 
     In still another aspect of this document, there is a method of adjusting audio properties of DTV by employing a 3D pointing device, wherein the DTV can receive signals from the 3D pointing device that recognizes 3D motion, the method comprising outputting audio through an audio output device, selecting a specific one of one or more functions for controlling the audio properties, sensing motion of the 3D pointing device, and executing the selected specific function, while varying a change speed of a value regarding the specific function, in consideration of a current value regarding the sensed motion and the specific function. 
     The method may further comprise entering a recognition mode for recognizing the motion of the 3D pointing device according to a user&#39;s manipulation on the 3D pointing device. 
     The specific function may comprise a volume control function or a tone control function. 
     In the execution of the specific function, an increment and decrement of a value regarding the specific function may be previously set according to a direction of the sensed motion, and the value regarding the specific function is changed according to the direction of the sensed motion. 
     The change speed of the value regarding the specific function can be set by a user. 
     In still another aspect of this document, there is a DTV capable of receiving signals from a 3D pointing device that recognizes 3D motion, the DTV comprising a reception unit for receiving a radio signal from the 3D pointing device, and a controller for receiving the radio signal from the 3D pointing device through the reception unit, sensing motion of the 3D pointing device, and controlling an execution speed of a function provided by the DTV according to a degree of the sensed motion. 
     The controller may enter a recognition mode for recognizing the motion of the 3D pointing device according to a user&#39;s manipulation on the 3D pointing device. 
     The controller may control the execution speed in consideration of at least one of the function itself, a distance of the sensed motion, and a speed of the sensed motion. 
     The controller may control the execution speed in consideration of a current value regarding the function. 
     The controller may control the execution speed in consideration of a direction of the sensed motion, wherein an increment and decrement of a value regarding the function are previously set according to the direction of the sensed motion. 
     The function may comprise a function for controlling an output state of information. Here, the function may comprise a an audio quality control function (e.g., volume, balance, bass, treble, etc.) or a picture quality control function (e.g., brightness, tint, color, contrast, saturation, sharpness, etc.). 
     The execution speed can be set by a user. 
     In further still another aspect of this document, there is a DTV capable of receiving signals from a 3D pointing device that recognizes 3D motion, the DTV comprising a reception unit for receiving a radio signal from the 3D pointing device, and a controller for executing various functions provided by the DTV, receiving a radio signal from the 3D pointing device through the reception unit, and sensing motion of the 3D pointing device. In the case in which a second function different from a first function is selected while the first function is executed at a first response speed with respect to the motion of the 3D pointing device, the controller executes the second function at a second response speed different from the first response speed with respect to the motion of the 3D pointing device. 
     The controller may enter a recognition mode for recognizing the motion of the 3D pointing device according to a user&#39;s manipulation on the 3D pointing device. 
     The first and second response speeds can have different values although at least one of a distance of the motion of the 3D pointing device, a speed of the motion of the 3D pointing device, and a direction of the motion of the 3D pointing device is identical. 
     The first and second response speeds may be decided in consideration of at least one of a corresponding function itself and a current value regarding the corresponding function. 
     The first and second response speeds can be set by a user. 
     In further still another aspect of this document, there is a DTV capable of receiving signals from a 3D pointing device that recognizes 3D motion, the DTV comprising a reception unit for receiving a radio signal from the 3D pointing device, and a controller for executing various functions provided by the DTV, receiving a radio signal from the 3D pointing device through the reception unit, and sensing motion of the 3D pointing device. In the case in which a specific one of one or more functions for controlling audio properties is selected, the controller executes the specific function, while varying a change speed of a value regarding the specific function, in consideration of the motion of the 3D pointing device and a current value regarding the specific function. 
     The controller may enter a recognition mode for recognizing the motion of the 3D pointing device according to a user&#39;s manipulation on the 3D pointing device. 
     The specific function may comprise an audio quality control function (e.g., volume, balance, bass, treble, etc.) or a picture quality control function (e.g., brightness, tint, color, contrast, saturation, sharpness, etc.) 
     The controller may vary the change speed of the value regarding the specific function according to a direction of the sensed motion, wherein an increment and decrement of the value regarding the specific function are previously set according to the direction of the sensed motion. 
     The change speed of the value regarding the specific function can be set by a user. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The implementation of this document will be described in detail with reference to the following drawings in which like numerals refer to like elements. 
         FIG. 1  is a diagram schematically showing a system to which this document is applied; 
         FIG. 2   a  is a diagram showing an exemplary external shape of a 3D pointing device  10  in accordance with an embodiment of this document; 
         FIG. 2   b  is a block diagram showing the construction of the 3D pointing device  10  in accordance with an embodiment of this document; 
         FIG. 3  is a block diagram showing the construction of DTV  20  in accordance with an embodiment of this document; 
         FIG. 4  is a flowchart illustrating a method of executing functions of DTV by employing the 3D pointing device in accordance with a first embodiment of this document; 
         FIG. 5  is a diagram illustrating the concept of an execution speed; 
         FIGS. 6 and 7  are diagrams illustrating a difference in the execution speed according to functions; 
         FIG. 8  is a graph showing an example in which the execution speed of a function is varied while the 3D pointing device  10  is moved; 
         FIG. 9  is a diagram illustrating a change in the execution speed depending on a motion direction of the 3D pointing device  10 ; 
         FIG. 10  is a flowchart illustrating a method of executing functions of DTV by employing the 3D pointing device in accordance with a second embodiment of this document; and 
         FIG. 11  is a flowchart illustrating a method of executing functions of DTV employing the 3D pointing device in accordance with a third embodiment of this document. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The above objects, specific merits and novel characteristics of this document will become more apparent from the following detailed description taken in conjunction with the accompanying drawings. Hereinafter, implementations of this document will be described in detail with reference to the attached drawings. The same reference numbers will be used throughout the drawings and specification to refer to the same or like parts. Further, in describing this document, detailed description on the known functions and constructions will be omitted if it is determined to make the gist of this document unnecessarily vague. 
       FIG. 1  is a diagram schematically showing a system to which this document is applied. This document, as shown in  FIG. 1 , can be applied to a system comprising a 3D pointing device  10  and DTV  20 . 
     The 3D pointing device  10  can sense 3D motion and transmit information about the sensed 3D motion to the DTV  20 . The 3D motion can correspond to commands for controlling the DTV  20 . A user can transfer a specific command to the DTV  20  by moving the 3D pointing device  10  on the space. The 3D pointing device  10  can be equipped with various key buttons. A user can input a variety of commands through the key buttons. 
     The DTV  20  can receive a broadcasting signal from a broadcasting station  30  and output the received broadcasting signal. Further, the DTV  20  can comprise an apparatus that can be connected to an Internet  40  according to the transmission control protocol/Internet protocol (TCP/IP). 
       FIG. 2   a  is a diagram showing an exemplary external shape of the 3D pointing device  10  in accordance with an embodiment of this document.  FIG. 2   b  is a block diagram showing the construction of the 3D pointing device  10  in accordance with an embodiment of this document. The 3D pointing device  10  in accordance with an embodiment of this document is described in detail below with reference to  FIGS. 2   a  and  2   b.    
     The 3D pointing device  10  in accordance with an embodiment of this document can comprise a sensor  101 , a key button  102 , memory  103 , a transmission unit  104 , and a controller  105 . 
     The sensor  101  senses 3D motion of the 3D pointing device  10 . The sensor  101  can comprise at least one of a gyro sensor, a gravity sensor, an inertia sensor, a geomagnetic sensor, and an accelerometer and can sense 3D motion of the 3D pointing device  10  by employing one of the sensors or through a combination of two or more of the sensors. 
     The key button  102  is an apparatus for receiving various pieces of information or commands from a user. For example, the key button  102  can be disposed on the front surface of the 3D pointing device  10 , as shown in  FIG. 2   a.    
     The memory  103  stores a specific program for controlling an overall operation of the 3D pointing device  10 . The memory  103  stores data, which is input/output when the overall operation of the 3D pointing device  10  is executed by the controller  105 , various processed data, and so on temporarily or permanently. 
     The transmission unit  104  transmits information about motion sensed by the sensor  101 , or signals input through the key button  102  to the DTV  20 . 
     The controller  105  controls the constituent elements and is responsible for an overall operation of the 3D pointing device  10  in accordance with embodiments of this document. 
       FIG. 3  is a block diagram showing the construction of the DTV  20  in accordance with an embodiment of this document. The DTV in accordance with an embodiment of this document is described in detail below with reference to  FIG. 3 . 
     The DTV  20  can comprise a first reception unit  201 , a second reception unit  202 , a display  203 , an audio output unit  204 , a key input unit  205 , memory  206 , and a controller  207 . 
     The first reception unit  201  receives signals from the 3D pointing device  10 . The first reception unit  201  and the 3D pointing device  10  can communicate with each other according to a radio frequency (RF) communication method. 
     The second reception unit  202  receives broadcasting signals from the broadcasting station  30 . The broadcasting signals can comprise at least one of audio signals and video signals. Further, the broadcasting signals can comprise data broadcasting having text information. 
     The display  203  displays video information in response to a control signal output from the controller  207 . For example, the video information can comprise video signals, comprised in broadcasting signals received through the second reception unit  202 , a variety of graphic user interfaces (GUIs) provided by the DTV  20  or information indicating the status of the DTV  20 . 
     The audio output unit  204  is an apparatus for outputting audio information. The audio output unit  204  can comprise a speaker. 
     The key input unit  205  is an apparatus for receiving various pieces of information or commands from a user. For example, the key input unit  205  can be disposed on the front or side of the DTV  20 . 
     The memory  206  stores a specific program for controlling an overall operation of the DTV  20 . The memory  206  can store data, which is input/output when the overall operation of the DTV  20  is executed by the controller  207 , various processed data, and so on temporarily or permanently. 
     The DTV  20  can comprise, other than the above constituent elements, an apparatus that can connect to the Internet  40 , and audio/video (A/V) decoding means for decoding A/V signals received from the broadcasting station  30  or the Internet  40 . The A/V decoding means can be software processing means, or hardware processing means such as an additional multimedia chip. 
     The controller  207  controls the constituent elements and is responsible for an overall operation of the DTV  20  in accordance with embodiments of this document. 
     In this document, the DTV  20  performs functions in response to signals received from the 3D pointing device  10 . Information included in the signals, which are transmitted from the 3D pointing device  10  to the DTV  20 , may be various. 
     For example, the 3D pointing device  10  can transmit information itself about 3D motion of the 3D pointing device  10  to the DTV  20 . Here, the DTV  20  processes information about 3D motion of the 3D pointing device  10  and performs functions. 
     For example, the 3D pointing device  10  can process information about 3D motion thereof and transmit information about commands for executing functions, provided by the DTV  20 , to the DTV  20 . Here, the DTV  10  may not receive information itself about the 3D motion of the 3D pointing device  10 . 
     For example, the 3D pointing device  10  can transmit information about 3D motion of the 3D pointing device  10  and partially processed information of the information about the 3D motion to the DTV  20 . Here, the DTV  10  can process the remaining information necessary to perform embodiments of this document. 
     Hereinafter, a concrete operation of the DTV in accordance with embodiments of this document and a method of executing functions of DTV by employing the 3D pointing device in accordance with embodiments of this document are described in detail below. 
       FIG. 4  is a flowchart illustrating a method of executing functions of DTV by employing the 3D pointing device in accordance with a first embodiment of this document. The method of executing functions of DTV employing the 3D pointing device in accordance with a first embodiment of this document can be implemented in the system and the DTV  20  above described with reference to  FIGS. 1 and 3 . The method of executing functions of DTV by employing the 3D pointing device in accordance with a first embodiment of this document and an operation of the DTV  20  for implementing the method are described in detail below with reference to  FIG. 4  and pertinent drawings. 
     A recognition mode for recognizing motion of the 3D pointing device  10  is entered [S 300 ]. 
     The step S 300  can be performed by a user who manipulates the 3D pointing device  10 . The 3D pointing device  10  can comprise an additional button for entering the recognition mode. When a user presses the button, the 3D pointing device  10  and the DTV  20  enter the recognition mode. In response thereto, the 3D pointing device  10  and the DTV  20  can recognize motion of the 3D pointing device  10 . 
     Alternatively, the step S 300  can be performed by a user who presses the button  205  provided in the DTV  20 . For example, although the 3D pointing device  10  senses its motion and transmits a sensed signal to the DTV  20 , if the DTV  20  does not receive the sensed signal or disregards the sensed signal, the 3D pointing device  10  cannot enter the recognition mode. 
     A function provided by the DTV  20  is selected [S 310 ]. Functions provided by the DTV  20  in this document can comprise all functions, which can be executed by consecutive inputs according to motion of the 3D pointing device  10 . The functions provided by the DTV  20  can also comprise all functions for controlling the output state of information. Further, the functions provided by the DTV  20  can comprise all functions whose values may be changed when being recognized by a user. 
     For example, the functions provided by the DTV  20  can comprise a function of controlling audio properties, such as volume control, tone (sound quality, tone quality, timbre, balance, bass, treble etc.) control or equalizer control. 
     As another example, the functions provided by the DTV  20  can comprise a function of controlling video properties. Such control of the video properties refers to control of the picture quality, such as brightness, contrast, tint, color, saturation, sharpness, resolution, etc. 
     As still another example, the functions provided by the DTV  20  can comprise a channel change function, a screen scroll function, and so on. For example, in the case in which the DTV  20  is connected to a web page through the Internet and information provided by the connected web page cannot be displayed on one screen, the DTV  20  can provide the screen scroll function. 
     The step S 310  can be executed when the button, provided in the 3D pointing device  10  or the DTV  20  and matching a specific function, is pressed. Meanwhile, in the case in which the specific function matches a specific motion of the 3D pointing device  10 , a user can select the specific function by moving the 3D pointing device  10  according to the matching. 
     When the 3D pointing device  10  and the DTV  20  enter the recognition mode, the controller  207  receives a radio signal from the 3D pointing device  10  through the first reception unit  201  and senses the motion of the 3D pointing device  10  [S 320 ]. The controller  207  executes the selected function while controlling an execution speed of the function selected in the step S 300  according to the degree of the motion of the 3D pointing device  10 , which is sensed in the step S 320  [S 330 ]. 
     The execution speed refers to a speed that responds to motion of the 3D pointing device  10  when the DTV  20  executes the selected function.  FIG. 5  is a diagram illustrating the concept of an execution speed. Referring to  FIG. 5 , when the 3D pointing device  10  moves from a point A to a point B, the controller  207  gradually changes the audio volume from 40 to 50. The execution speed refers to a change amount of the audio volume with respect to the motion of the 3D pointing device  10  from the point A to the point B. The execution speed may be constant or variable while the audio volume changes from 40 to 50. 
     The controller  207  can control the execution speed by considering at least one of the selected function itself, the distance of the sensed motion, and the speed of the sensed motion. For example, the controller  207  can increase the execution speed gradually as the distance of the sensed motion increases, while executing the selected function according to a default execution speed with respect to the selected function. For example, the controller  207  can increase the execution speed when the speed of the sensed motion is fast, but decrease the execution speed when the speed of the sensed motion is slow. 
       FIGS. 6 and 7  are diagrams illustrating a difference in the execution speed according to functions. In  FIGS. 6 and 7 , the x axis denotes a distance where the 3D pointing device  10  has moved and the y axis denotes a value pertinent to a function. For example, the y axis can denote the audio volume. 
     As shown in  FIG. 6 , a first function and a second function can have different execution speeds. For example, in  FIG. 6 , in the case in which the 3D pointing device  10  has moved ‘d’, the first function can be executed as much as a value corresponding to dV 1  can be changed, and the second function can be executed as much as a value corresponding to dV 2 . As described above, the first function and the second function have different execution speeds with respect to the motion of the 3D pointing device  10 . Further, in  FIG. 6 , although the 3D pointing device  10  moves the same distance, the change amount of a value regarding the first function is greater than the change amount of a value regarding the second function. 
       FIG. 7  is a diagram illustrating an execution speed that varies according to the distance of motion of the 3D pointing device  10 . Referring to  FIG. 7 , while the 3D pointing device  10  moves, the execution speeds of a first function and a second function are constant. In the case of a third function, as a motion distance of the 3D pointing device  10  increases, the execution speed of the third function gradually increases. Further, in the case of a fourth function, when the 3D pointing device  10  moves up to a distance dv, the execution speed of the fourth function gradually increases, but when the 3D pointing device  10  moves a distance exceeding the distance dv, the execution speed of the fourth function gradually decreases. 
     The controller  207  can also control the execution speed in consideration of a current value regarding the selected function. 
       FIG. 8  is a graph showing an example in which the execution speed of a function is varied while the 3D pointing device  10  is moved. For example, while the 3D pointing device  10  moves, the controller  207  can control the execution speed of the selected function in consideration of a current value and the distance of motion with respect to the selected function. In  FIG. 8 , it is assumed that the 3D pointing device  10  consecutively moves a distance, corresponding to 3d, from x 1  to x 4  and the y axis denotes the audio volume. 
     While the 3D pointing device  10  consecutively moves the distance, corresponding to 3d, from x 1  to x 4 , the audio volume changes from V 1  to V 4  while the speed of the audio volume vanes, as shown in  FIG. 8 . For example, when the 3D pointing device  10  moves the distance d from x 1  to x 2 , the audio volume changes from V 1  to V 2 . When the 3D pointing device  10  continues to move to reach x 3 , the audio volume changes up to V 3 . Here, when comparing with a section A and a section B, the 3D pointing device  10  has moved the same distance d, but the change amounts of the audio volume are different from each other (dV A &gt;dV B ). 
     Referring to  FIG. 8 , the controller  207  can control the change speed of the audio volume in consideration of a current value of the audio volume as the 3D pointing device  10  moves. 
     An increment and decrement of a value with respect to the selected function may be previously set according to the direction of motion of the 3D pointing device  10 . Here, the controller  207  can control the execution speed in consideration of the direction of the sensed motion. 
       FIG. 9  is a diagram illustrating a change in the execution speed depending on a motion direction of the 3D pointing device  10 . It is assumed that when the 3D pointing device  10  moves to the right, a value with respect to the selected function increases and when the 3D pointing device  10  moves to the left, a value with respect to the selected function decreases. 
     For example, referring to  FIG. 9 , in the case in which a user moves the 3D pointing device  10  to the left from a point P 1  to a point P 2  by a distance d, the audio volume decreases from V 6  to V 5 . In the case in which a user moves the 3D pointing device  10  to the right from the point P 1  to a point P 4  by a distance d, the audio volume increases from V 6  to V 7 . As shown in  FIG. 9 , when a user moves the 3D pointing device  10  from the point P 1  to the left and when a user moves the 3D pointing device  10  from the point P 1  to the right by the same distance, the change amounts of the audio volume can differ.  FIG. 9  shows an example in which when the 3D pointing device  10  moves to the right rather than when the 3D pointing device  10  moves to the left, the change amount of the audio volume with respect to the distance of motion of the 3D pointing device  10  is great, that is, the execution speed of the volume control function is fast. 
     The controller  207  can control the change speed of the audio volume in consideration of a current value of the audio volume as described above. In  FIG. 9 , in the case in which a current value of the audio volume is V 5  (the point P 2 ), when a user moves the 3D pointing device  10  to the right by the distance d 1 , the audio volume can change to V 7 . When a current value of the audio volume is V 6  (the point P 1 ), a user can change the audio volume up to V 7  by moving the 3D pointing device  10  to the right by the distance d greater than the distance d 1 . 
     The execution speed can be set by a user. For example, a user can set an execution speed with respect to a specific function by employing a GUI provided by the DTV  20 . Further, a user can set an execution speed with respect to a specific function in various ways. Here, the DTV  20  can provide a user with various options for setting an execution speed with respect to a specific function through a GUI. For example, a user can set an execution speed with respect to a specific function constantly, or set an execution speed with respect to a specific function every section of a value regarding the specific function. Further, a user can set an execution speed with respect to a specific function to be dependent or independent on a motion speed of the 3D pointing device  20 . That is, the execution profiles may be pre-set, or may be set or selected by a user. For example, a first user may prefer a highly sensitive volume control profile. This user would set or select a profile that has a high slope. A second user may prefer a less sensitive volume control profile. This user would set or select a profile that has a lower slope. The setting or selection of a profile may be executed via one or more help screens or on-screen prompts. 
     Thus, with the present invention, various execution profiles may be used for various functions. The profiles include an execution speed that is dependent on at least one of the direction, speed and acceleration of the 3D pointing device. Execution profiles of different functions may be the same or may be different. 
     Also, the execution profiles may be linear or non-linear. A non-linear profile may include a first portion that has a first (e.g., high) slope, and a second portion that has a second (e.g., small) slope. Alternatively, there may be three slopes, with the first and third having a first (e.g., high) slope, and the second having a second (e.g., small) slope. 
       FIG. 10  is a flowchart illustrating a method of executing functions of DTV by employing the 3D pointing device in accordance with a second embodiment of this document. The method of executing functions of DTV by employing the 3D pointing device in accordance with a second embodiment of this document can be implemented in the system and the DTV  20  described with reference to  FIGS. 1 and 3 . The method of executing functions of DTV by employing the 3D pointing device in accordance with a second embodiment of this document and an operation of the DTV  20  for implementing the method are described in detail with reference to  FIG. 10  and pertinent drawings. 
     A recognition mode for recognizing motion of the 3D pointing device  10  is entered [S 400 ]. The step S 400  corresponds to the step S 300  of  FIG. 4 . 
     When a first function provided by the DTV  20  is selected [S 410 ], the controller  207  executes the first function at a first response speed with respect to the motion of the 3D pointing device  10  [S 420 ]. The first response speed with respect to the first function is previously set. 
     If a second function provided by the DTV  20  is selected while the step S 410  is being executed [S 430 ], the controller  207  executes the second function at a second response speed with respect to the motion of the 3D pointing device  10  [S 440 ]. The second response speed with respect to the second function is previously set. The second response speed may differ from the first response speed. 
     From  FIGS. 6 to 8 , it can be seen that when a function selected by a user changes, a response speed with respect to motion of the 3D pointing device  10  changes. For example, the first and second response speeds may have different values although at least one of the distance of motion of the 3D pointing device, the speed of the motion of the 3D pointing device, and the direction of the motion of the 3D pointing device is identical. Response speeds with respect to the distance of motion, the speed of motion, and the direction of motion of the 3D pointing device have already been described above in connection with the first embodiment of this document, and further description thereof is omitted. 
     The first and second response speeds can be decided in consideration of at least one of a corresponding function itself, and a current value with respect to the corresponding function. This also has been described above in connection with the first embodiment of this document, and further description thereof is omitted. 
     The first and second response speeds can be set by a user in the same manner as the first embodiment of this document. 
       FIG. 11  is a flowchart illustrating a method of executing functions of DTV employing the 3D pointing device in accordance with a third embodiment of this document. The method of executing functions of DTV employing the 3D pointing device in accordance with a third embodiment of this document can be implemented in the system and the DTV  20  described with reference to  FIGS. 1 and 3 . The method of executing functions of DTV employing the 3D pointing device in accordance with a third embodiment of this document and an operation of the DTV  20  for implementing the method are described in detail with reference to  FIG. 11  and pertinent drawings. 
     The controller  207  outputs audio through the audio output unit  204  [S 500 ]. For example, the controller  207  can output A/V broadcasting, which is received through the second reception unit  202 , through the audio output unit  204  while displaying the A/V broadcasting through the display  203 . For example, when the DTV  20  is equipped with an apparatus accessible by an Internet, the controller  207  can output audio, received over the Internet, through the audio output unit  204 . 
     A recognition mode for recognizing motion of the 3D pointing device  10  is entered [S 510 ]. The step S 510  corresponds to the step S 300  of  FIG. 4 . 
     A specific one of one or more functions for adjusting the audio properties is selected [S 520 ]. The step S 520  can be performed in various ways, as described above in connection with the step S 310 . For example, the specific function selected in the step S 520  can be a volume control function or a tone control function. 
     The controller  207  receives a radio signal from the 3D pointing device  10  through the first reception unit  201  and senses motion of the 3D pointing device  10  [S 530 ]. 
     The controller  207  executes the specific function, while varying a change speed of a value with respect to the specific function, in consideration of the sensed motion of the 3D pointing device  10  and a current value regarding the selected specific function [S 540 ]. 
     In the step S 540 , the controller  207  can vary the change speed of the value regarding the specific function according to the direction of the sensed motion. An increment and decrement of the value regarding the specific function depending on the direction of the sensed motion may be previously set. 
     The change speed of the value regarding the specific function can be set by a user in the same manner as the above first or second embodiment of this document. 
     The method of executing functions of DTV by employing the 3D pointing device and the method of adjusting the audio properties of DTV by employing the 3D pointing device in accordance with this document, which have been described above, can be recorded into a computer-readable recording medium as a program for being executed by a computer and then provided. 
     The method of executing functions of DTV by employing the 3D pointing device and the method of adjusting the audio properties of DTV by employing the 3D pointing device in accordance with this document can be executed through a software program. When the method is executed through a software program, the constituting elements of this document become code segments that execute a specific task. The program or code segments can be stored in a processor-readable medium or transmitted through computer data signals combined with carrier in a transmission medium or a communication network. 
     The computer-readable recording medium can comprise all kinds of recording devices in which data readable by a computer system is stored. For example, the computer-readable recording medium can comprise ROM, RAM, CD-ROM, DVD±ROM, magnetic tapes, floppy disks, hard disks, optical data storages, and so on. Further, the computer-readable recording medium can be distributed into computer systems connected over a network, so codes readable by a computer can be stored and executed in a distributed manner. 
     While this document has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that this document is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. 
     The DTV that is able to receive signals from the 3D pointing device, the method of executing functions of DTV by employing the 3D pointing device, and the method of adjusting the audio properties of DTV by employing the 3D pointing device in accordance with this document have the following advantages. 
     First, in accordance with this document, in executing a function of the DTV according to motion of the 3D pointing device, an execution speed of the DTV function is varied according to the degree of motion of the 3D pointing device. Accordingly, a user can use the 3D pointing device efficiently and conveniently in various environments or situations. 
     Second, in accordance with this document, when executing a function of the DTV by employing the 3D pointing device, fine control is possible according to a current value or a current section of the function. For example, although a user greatly moves the 3D pointing device, an execution speed of the function can be set slowly. For example, although a user moves the 3D pointing device only a little, an execution speed of the function can be set fast. 
     Third, in accordance with this document, a user can set a response speed of the DTV with respect to the 3D pointing device, as needed.