Abstract:
In one embodiment, an apparatus includes a network interface, an acoustic waveguide, and an arrangement. The network interface is arranged to communicate on a network, and is further configured to obtain a signal from the network. The arrangement is configured to transform the signal into an acoustic wave and to provide the acoustic wave to the acoustic waveguide. The acoustic waveguide is configured to direct the acoustic wave in a path.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    The present application claims priority of U.S. Provisional Patent Application No. 61/777,133, filed Mar. 12, 2013, which is incorporated herein by reference in its entirety. 
     
    
     TECHNICAL FIELD 
       [0002]    The disclosure relates generally to network communications. More particularly, the disclosure relates to a method and apparatus for efficiently directing sound at listeners during realtime communications using a conference phone device. 
       BACKGROUND 
       [0003]    Conference phones are often used in relatively open environments, e.g., in a conference room or an office. Typically, loudspeakers of conference phones are direct radiation loudspeakers. A loudspeaker that is a direct radiator includes a diaphragm that is directly coupled to air. The acoustic output associated with a direct radiator is generally non-directional, e.g., the acoustic output is generally directed in a vertical direction and not in a horizontal direction. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0004]    The disclosure will be readily understood by the following detailed description in conjunction with the accompanying drawings in which: 
           [0005]      FIG. 1  is a block diagram representation of a device that includes an acoustic waveguide in accordance with an embodiment. 
           [0006]      FIG. 2  is a diagrammatic representation of a speaker arrangement in accordance with an embodiment. 
           [0007]      FIG. 3  is a diagrammatic representation of a speaker arrangement, e.g., speaker arrangement  202  of  FIG. 2 , that has an associated microphone in accordance with an embodiment. 
           [0008]      FIG. 4A  is a block diagram side-view representation of a conference phone that includes an acoustic waveguide that directs sound in accordance with an embodiment. 
           [0009]      FIG. 4B  is a block diagram top-view representation of a conference phone that includes an acoustic waveguide, e.g., conference phone  430  of  FIG. 4A , that directs sound in accordance with an embodiment. 
           [0010]      FIG. 5  is a diagrammatic top-view representation of a phase plug, e.g., phase plug  116  of  FIG. 2 , in accordance with an embodiment. 
           [0011]      FIG. 6  is a block diagram representation of a conference station that includes a speaker arrangement with an acoustic waveguide in accordance with an embodiment. 
       
    
    
     DESCRIPTION OF EXAMPLE EMBODIMENTS 
     General Overview 
       [0012]    According to one aspect, an apparatus includes a network interface, an acoustic waveguide, and an arrangement. The network interface is arranged to communicate on a network, and is further configured to obtain a signal from the network. The arrangement is configured to transform the signal into an acoustic wave and to provide the acoustic wave to the acoustic waveguide. The acoustic waveguide is configured to direct the acoustic wave in a path. 
       DESCRIPTION 
       [0013]    Conference phones or speaker phones, e.g., conference stations such as an Internet Protocol (IP) conference station, are often used in meeting room environments to enable groups of people in the meeting room environments to participate in conference calls. As listeners in a meeting room environment are typically positioned around a conference station, the ability to direct sound from a loudspeaker of the conference station at the listeners would enhance the quality of sound perceived by the listeners. In addition, the ability to direct sound from a conference station at a listener, e.g., in a direct path to a listener, may reduce the amount of power used by the conference station, as loudspeaker sensitivity may be improved and sound may be directed at the listeners with improved efficiency and reduced distortion. A reduction in the amount of power due to increased acoustic efficiency may enable the size of a power amplifier used to power a conference station to be reduced. 
         [0014]    By providing a realtime communications device such as a conference station that has a loudspeaker with an acoustic waveguide, sound waves produced by the loudspeaker may be directed towards a listener in a substantially direct path rather than in a primarily upward direction. In one embodiment, a conference station may have a loudspeaker, e.g., a loudspeaker mounted within the conference station, as well as a loudspeaker driver and a phase plug that is acoustically coupled to an acoustic waveguide. It should be appreciated that the loudspeaker driver may generally also be acoustically coupled to the acoustic waveguide. An acoustic waveguide is generally a structure which is configured to guide air or, more particularly, sound waves in the air. The shape of an acoustic waveguide may be configured, for example, to direct sound in at least one particular direction. 
         [0015]    A conference station generally also includes a microphone, or a component which captures sound and allows the sound to be transmitted through the conference station to a party, e.g., a party using another conference station on a communications network. The placement of a microphone of a conference station relative to an acoustic waveguide of the conference station may vary. For example, a microphone may be positioned substantially above an acoustic waveguide arranged to improve echo-cancellation, and a microphone may be positioned substantially below an acoustic waveguide to reduce cone filtering. 
         [0016]    The power requirements of a conference station which includes an acoustic waveguide may be less than the power requirements of a conference station which does not include an acoustic waveguide. As an acoustic waveguide directs sound in a direct path to a user of the conference station, e.g., a conference call participant, power requirements may be reduced as loudspeaker sensitivity is improved and sound may be provided to the user more efficiently. By way of example, by directing frequencies of approximately one kilohertz (kHz) and higher in a path at a user, sound may efficiently be provided to the user. 
         [0017]    Referring initially to  FIG. 1 , a realtime communications device that includes an acoustic waveguide will be described in accordance with an embodiment. A realtime communications device  100 , e.g., a conference station, includes a loudspeaker  108  and an enclosure  104 . At least one loudspeaker driver  112 , a phase plug  116 , and an acoustic waveguide  120  may be contained within enclosure  104 . Typically, loudspeaker  108  and at least one loudspeaker driver  112  may be considered to be an overall loudspeaker. 
         [0018]    Loudspeaker  108  may generally be a transducer such as compression-loaded transducer, and cooperates with at least one loudspeaker driver  112  to convert a signal, as for example an electrical audio signal, into acoustic waves. In the described environment, the acoustic waves may be guided by acoustic waveguide  120 . At least one loudspeaker driver  112  is typically included in device  100  to effectively reproduce different frequency ranges from an obtained signal. In general, substantially separate loudspeaker drivers  112  may include, but are not limited to including a relatively high frequency driver such as a tweeter, relatively low frequency drivers such as woofers and subwoofers, and a mid-range frequency driver such as a mid-range speaker. It should be appreciated that any number of loudspeaker drivers  112  may be included in device  100 . 
         [0019]    Phase plug  116  may be arranged to reduce echo cancellation, and to augment the relatively high frequency response associated with loudspeaker  108 . That is, phase plug  116  reduces wave cancelling with respect to acoustic waves by reducing collisions between acoustic waves having a relatively high frequency. Phase plug  116  is acoustically coupled to acoustic waveguide  120 . 
         [0020]      FIG. 2  is a diagrammatic cross-sectional side-view representation of an overall speaker arrangement that includes an acoustic waveguide in accordance with an embodiment. An overall speaker arrangement  202  includes a loudspeaker driver  212  that is a part of an overall loudspeaker, a phase plug  216 , an acoustic waveguide  220 . Acoustic waveguide  220 , which includes an open area  218 , is positioned below loudspeaker driver  212 . At least one open area  222  is arranged within phase plug  216 , as is shown in more detail in  FIG. 5 . Open areas  222  of phase plug  216  are effectively located at least partially between closed areas  552 . In one embodiment, closed areas  552  may be formed from, e.g., filled with, a plastic material. Open area  218  and open areas  222  of phase plug  216  provide space in which air particles may oscillate, and in which acoustic waves may propagate. 
         [0021]    Acoustic waveguide  220  may be configured, as previously mentioned, to direct acoustic waves, or sound, substantially directly to users of a device that includes overall speaker arrangement  202 . Acoustic waveguide  220  generally directs acoustic waves after the acoustic waves are propagated through open areas  218 ,  222 . Thus, with respect to a device (not shown) such as a conference station in which overall speaker arrangement  202  is located, acoustic waves may be directed by acoustic wave guide  220  in directions with an x-axis component and/or a y-axis component. That is, acoustic waves may be guided by acoustic wave guide  220  along a path in at least one horizontal direction. It should be understood that although waves may be directed in any direction, as for example in a vertical direction or a direction with a z-axis component, acoustic waves are typically guided in at least one horizontal direction. 
         [0022]    As shown, a top surface of acoustic waveguide  220  is curved. The shape of the curvature of the top surface of acoustic waveguide  220  may vary widely, and may depend upon a variety of different factors. The different factors may include, but are not limited to including, the directions in which acoustic waves are to be directed, a desired frequency response, and/or power requirements. In general, acoustic waves are to be directed such that energy is focused on a listener, or a user of a device that includes overall speaker arrangement  202 , and such that substantially minimal energy is directed away from the listener. It should be appreciated that although acoustic waveguide  220  is shown as having a bottom surface that is substantially flat or planar, the bottom surface of acoustic waveguide  220  is not limited to being substantially flat or planar. For example, a bottom surface of acoustic waveguide  220  may have approximately the same curvature as a top surface of acoustic waveguide  220 . 
         [0023]    Typically, overall speaker arrangement  202  has an associated microphone that captures sound, e.g., sound that is local with respect to overall speaker arrangement  202 . For example, a realtime communications device that includes overall speaker arrangement  202  typically also includes a microphone.  FIG. 3  is a diagrammatic representation of overall speaker arrangement with an associated microphone in accordance with an embodiment. An overall speaker arrangement  202 ′ has an associated microphone  324 , or a transducer that is arranged to convert sound into an electrical signal. As shown, microphone  324  is positioned at least partially over a curved top surface of acoustic waveguide  220 . By positioning microphone  324  substantially above acoustic waveguide  220 , the echo-cancelling performance associated with microphone  324  may be improved. When microphone  324  is positioned substantially above acoustic waveguide  220 , microphone  324  may be positioned away from a path of energy directed by waveguide  220 . 
         [0024]    Although microphone  324  may preferably be positioned substantially above acoustic waveguide  220 , microphone  324  is not limited to being placed substantially above acoustic waveguide  220 . It should be appreciated, however, that when microphone  324  is positioned substantially below acoustic waveguide  220 , or close to a bottom of overall speaker arrangement  202 ′, acoustic cone filtering and interference may be substantially minimized. Thus, the placement of microphone  324  with respect to overall speaker arrangement  202 ′ may vary depending upon the requirements of a particular system, as for example a conference phone, that includes microphone  324  and overall speaker arrangement  202 ′. 
         [0025]    With reference to  FIGS. 4A and 4B , the directionality of acoustic waves produced by a conference station such as a conference call will be described in accordance with an embodiment.  FIG. 4A  is a block diagram side-view representation of a conference phone that includes an acoustic waveguide that directs sound, and  FIG. 4B  is a block diagram top-view representation of the conference phone. A conference phone  430  that includes an acoustic waveguide is configured to direct acoustic waves  434 , or sound waves, at one or more listeners. Acoustic waves  434 , as shown, include at least one horizontal component. That is, each acoustic wave  434  is propagated in a direction along an x-axis and/or a direction along a y-axis. Acoustic waves  434  may also include a vertical component, i.e., a component relative to a z-axis, in addition to at least one horizontal component. 
         [0026]    As a user (not shown) of conference phone  430  may be positioned next to conference phone  430  relative to the x-axis and/or the y-axis, acoustic waves  434  that are propagated in a direction along the x-axis and/or a direction along the y-axis are effectively directed substantially directly at the user. Thus, conference phone  430  provides acoustic waves to a user (not shown) efficiently. 
         [0027]      FIG. 6  is a block diagram representation of a conference station that includes a speaker arrangement with an acoustic waveguide in accordance with an embodiment. A conference station  630  includes a speaker arrangement  600  which has an acoustic waveguide  620  that is arranged to direct acoustic sound waves in particular directions, e.g., substantially directly at a listener who is using conference station  630 . Speaker arrangement  600  also includes a driver  672 , e.g., a loudspeaker driver, that is arranged to convert a received signal into an acoustic sound wave, and may be acoustically coupled to acoustic waveguide  620 . 
         [0028]    Conference station  630  also includes a processor  660 , logic  664 , and a network interface  676 . Logic  664  may include software and/or hardware logic, and processor  660  is configured to execute software logic. Conference call logic  668 , which is included in logic  664 , allows conference station  630  to be used as an endpoint of a conference call, and generally supports the ability for conference station  630  to dial into and to participate in a conference call using network interface  676 . Network interface  676  may include at least one input/output port (not shown) that allows conference station  630  to connect to a communications network, e.g., telephone network or a network that supports voice over IP (VoIP). Through network interface  676 , conference station  630  may connect to nodes on a communications network, e.g., a node such as a conference call server, such that signals may be exchanged between conference station  630  and the nodes. In general, nodes on a communication network may be endpoints associated with a conference call. 
         [0029]    Conference station  630  also includes a microphone arrangement  678  that includes at least one microphone  624  arranged to capture sound from an environment around conference station  630 . The position of microphone  624  with respect to speaker arrangement  600  may vary. As previously mentioned, microphone  624  may be positioned substantially above acoustic waveguide  620  relative to a vertical axis, e.g., to improve the echo-cancelling performance of conference station  630 . It should be appreciated, however, that microphone  624  is not limited to being positioned above acoustic waveguide  620  and may be positioned below acoustic waveguide  620  relative to the vertical axis, e.g., close to a surface on which conference station  630  is placed, in an effort to reduce acoustic cone filtering. 
         [0030]    Although only a few embodiments have been described in this disclosure, it should be understood that the disclosure may be embodied in many other specific forms without departing from the spirit or the scope of the present disclosure. By way of example, the location of a microphone in a conference phone relative to the location of an acoustic waveguide may vary widely. Some applications, or overall system specifications, may benefit from the placement of a microphone over an acoustic waveguide relative to a vertical axis. Other applications, or overall system specifications, may benefit from the placement of a microphone below an acoustic waveguide relative to a vertical axis. 
         [0031]    The shape, e.g., curvature, associated with an acoustic waveguide may vary widely. Factors which may affect the shape of an acoustic waveguide may include, but are not limited to including, the size an overall speaker arrangement and/or the directions in which sound waves are to be directed. 
         [0032]    While a waveguide has been described as being positioned substantially below a loudspeaker within a conference phone device, relative to a vertical axis, a waveguide may instead be placed substantially above a loudspeaker within a conference phone device, relative to a vertical axis, without departing from the spirit or the scope of the disclosure. For example, when a waveguide is positioned above a loudspeaker, a reflector may be used to effectively reverse the phase of sound waves coming from the loudspeaker. 
         [0033]    The embodiments may be implemented as hardware and/or software logic embodied in a tangible medium that, when executed, is operable to perform the various methods and processes described above. That is, the logic may be embodied as physical arrangements, modules, or components. A tangible medium may be substantially any computer-readable medium that is capable of storing logic or computer program code which may be executed, e.g., by a processor or an overall computing system, to perform methods and functions associated with the embodiments. Such computer-readable mediums may include, but are not limited to including, physical storage and/or memory devices. Executable logic may include, but is not limited to including, code devices, computer program code, and/or executable computer commands or instructions. 
         [0034]    It should be appreciated that a computer-readable medium, or a machine-readable medium, may include transitory embodiments and/or non-transitory embodiments, e.g., signals such as signals embodied in carrier waves. That is, a computer-readable medium may be associated with non-transitory tangible media and transitory propagating signals. 
         [0035]    The steps associated with the methods of the present disclosure may vary widely. Steps may be added, removed, altered, combined, and reordered without departing from the spirit of the scope of the present disclosure. Therefore, the present examples are to be considered as illustrative and not restrictive, and the examples is not to be limited to the details given herein, but may be modified within the scope of the appended claims.