Patent Publication Number: US-8526589-B2

Title: Multi-channel telephony

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS AND PRIORITY CLAIM 
     This application is a continuation of U.S. Non-Provisional application Ser. No. 11/847,619, entitled “MULTI-CHANNEL TELEPHONY”, filed Aug. 30, 2007, which is incorporated herein by reference in its entirety. 
    
    
     FIELD OF THE DISCLOSURE 
     The present disclosure relates to communications, and more specifically to providing multi-channel telephony. 
     BACKGROUND 
     Conferences are often conducted with multiple participants. A conference will typically include a number of different speakers throughout the duration of the conference. When attending a conference in person, a participant has the luxury of utilizing sensory information, including vision and the timbre effect of sound, to determine helpful information about the speaker. Unfortunately, face-to-face conferences are not always possible due to geographical or other constraints. Therefore, many conferences occur over communication systems, such as telephone systems configured for conference calling, or video conference systems. 
     Many communication systems are limited to transmitting single channel audio signals between users. Therefore, when conferences occur over typical communication systems, spatial reference is often lost through the single channel communication. It is often difficult to determine which participant is speaking during a conference call when multiple participants sound similar or when there are a large number of participants on the conference call. Accordingly, there is a continuing need to improve communication systems. 
     SUMMARY 
     Techniques for providing multi-channel telephony are described herein. In different aspects, a multi-channel telephony apparatus may include a sound interface configured to process a multi-channel sound signal including at least one of causing speakers to emit multi-channel sound or receiving multi-channel sound from microphones and a network interface configured to transmit the multi-channel sound signal from the sound interface to one or more communication lines of a telephone network. In some aspects, a dialer may be configured with the network interface to establish a connection with the telephone network. 
     In another aspect of the disclosure, an apparatus may include a communication processor operably connected to a telephone network configured as a multi-channel transport path. The apparatus may further include a sound interface for facilitating connections with two or more speakers and at least one microphone, and an audio processor in connection between the sound interface and the communication processor, the audio processor converting a communication signal from the communication processor to a sound signal for the sound interface. 
     In still another aspect of the disclosure, a method for providing multi-channel telephony may include connecting a multi-channel telephone to a multi-channel network using a call identifier, establishing a protocol between the multi-channel telephone and the network to facilitate provide at least two-channel sound to the multi-channel telephone, and providing multi-channel sound to the multi-channel telephone. 
     Other systems, methods, and/or computer program products according to embodiments will be or become apparent to one with skill in the art upon review of the following drawings and detailed description. It is intended that all such additional systems, methods, and/or computer program products be included within this description, be within the scope of the present disclosure, and be protected by the accompanying claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The detailed description is set forth with reference to the accompanying figures. In the figures, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The same reference numbers in different figures indicate similar or identical items. 
         FIG. 1  is a schematic of an illustrative environment including multi-channel telephony. 
         FIG. 2  is a block diagram of an illustrative architecture of a multi-channel telephony system. 
         FIG. 3  is a block diagram of an illustrative architecture of another, more advanced multi-channel telephony system. 
         FIG. 4  is an illustrative apparatus for providing multi-channel telephony, according to an aspect of the disclosure. 
         FIG. 5  is a flow diagram of an illustrative process of communication using a multi-channel telephony system. 
         FIG. 6  is a schematic of an alternative configuration of a multi-channel telephony system configured for a conference, according to another aspect of the disclosure. 
         FIG. 7  is a schematic of another alternative configuration of a multi-channel telephony system including a multi-user headset configuration, according to still another aspect of the disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Overview 
     A communication system according to embodiments disclosed herein may more closely simulate an in-person conference setting. For example, a communication system may provide multi-channel sound to a listener by combining traditional public switch telephone network (PSTN) lines to transmit stereo sound between users in a telephone conference. The communication system may include a number of additional features to enhance the sound quality and the transmission of the audio signals between users conversing on the system. 
     Apparatus and techniques for providing multi-channel telephony are described herein. Many specific details of certain embodiments are set forth in the following description and in  FIGS. 1 through 7  to provide a thorough understanding of such embodiments. Throughout the disclosure, several examples are described using stereo telephony, which is one example of multi-channel telephony. More generally, however, multi-channel telephony is intended to include providing communications using two or more channels to provide a user with a spatial aural presentation. 
       FIG. 1  is a schematic of an illustrative environment  100  including users communicating using multi-channel telephony. The environment  100  includes a first multi-channel telephony device (or telephone)  102  at a first location  104  and a second multi-channel telephone  106  at a second location  108 . The first and second multi-channel telephones  102 ,  106  facilitate a communication between a first set of users  110  and a second set of users  112 , respectively. The first set of users  110  may include any number of users  110 ( 1 ), . . . ,  110 (N), and accordingly the second set of users  112  may include users  112 ( 1 ), . . . ,  112 (R). The first and second sets of users  110 ,  112  may communicate over a telephone network  114  or other communication system in multi-channel sound. 
     According to exemplary embodiments, the first multi-channel telephone  102  includes a first set of speakers  116  and a first set of microphones  118  while the second multi-channel telephone  106  includes a second set of speakers  120  and a second set of microphones  122  to facilitate communications between the first and second set of users  110 ,  112 . Each set of speakers  116 ,  120  may include a plurality of speakers, such as speakers  116 ( 1 ), . . . ,  116 (M) and  120 ( 1 ), . . . ,  120 (Q), respectively. Similarly, each set of microphones  118 ,  122  may include a plurality of microphones, such as microphones  1   18 ( 1 ), . . . ,  118 (P) and  122 ( 1 ), . . . ,  122 (T), respectively. 
     In an illustrative communication in the environment  100 , the first set of users  110  may only include the first user  110 ( 1 ) while the second set of users  112  includes the users  112 ( 1 ) and  112 ( 2 ). The first user  110 ( 1 ) may greet the second set of users  112  such as by stating, “Hi Bob and Ted.” The first user&#39;s voice may be captured by the first set of microphones  118 , processed and/or transmitted by the first multi-channel telephone  102  to the second multi-channel telephone  106 , and emitted by the second set of speakers  120 . In one instance, the sound captured by the microphone  118 ( 1 ) may be transmitted via a first channel and emitted on the first speaker  120 ( 1 ). Accordingly, the microphone  118 (P) may transmit to the speaker  120 (Q). The sound emitted by the second set of speakers  120  may provide a spatial aural presentation of the first user&#39;s location relative to the first set of microphones  118 . Similarly, the second set of users  112  may reply to the first user, such as the user  112 ( 1 ) may say, “Hello Tina” while the user  112 ( 2 ) may say, “Good afternoon.” The first user  110 ( 1 ) may hear the communication from the second set of users  112  through speakers  116  such that the spatial configuration of the second set of users is represented. More specifically, the user  112 ( 1 ) may emit sound primarily through the speaker  116 ( 1 ) while the user  112 ( 2 ) may emit sound primarily though the speaker  116 (N), thus creating a spatial aural presentation of the second set of users  112  which may allow the first user  110 ( 1 ) to more easily distinguish voices between the users  112 ( 1 ),  112 ( 2 ). 
     Multi-Channel Apparatus 
       FIG. 2  is a block diagram of an illustrative architecture  200  of a basic multi-channel telephony system. The architecture  200  includes a multi-channel telephone  202  and a telephone network  204 . In some instances, the telephone network  204  may be a time-division multiplexed (TDM) digital network, including a PSTN, plain old telephone service (POTS), cellular network, integrated services digital network, or other TDM network, a combination of the foregoing, or the like. In one implementation, the connection between the multi-channel telephone  202  and the telephone network  204  may use multiple parallel transport paths, such as two or more PSTN telephone lines. 
     For example, the multi-channel telephone  202  may be connected to the PSTN using two twisted pair loops  206 . Each twisted pair loop  206  may transmit a single channel of audio to and from the multi-channel telephone  202 . In some instances, additional twisted pair loops may be used to transmit sound. Each twisted pair loop  206  may be in connection with an analog hybrid circuit (AHC)  208 , such as a left AHC  208 (L) and a right AHC  208 (R). As known to those familiar with analog telephony, the AHC  208  may route the majority of the electrical signal from a microphone through the twisted pair loop  206  while routing a small portion of the electrical signal through a set of speakers back to the user. The AHC  208  allows the speaker to hear her own voice by transmitting it back to her speakers for a low volume projection known as “sidetone”, while at the same time her voice is transmitted to remote listeners for a normal projection. 
     The multi-channel telephone  202  may also include a dialer  210  to facilitate completing a telephone call or other multi-channel telephony communication. The dialer  210  may be operably connected to the AHC  208 . The dialer  210  may be configured to dial a single number to connect the caller. In some instances, the dialer  210  may have to dial multiple numbers to connect the caller, such as when the architecture  200  uses two twisted pair loops  206  in a PSTN. In such instances, the dialer  210  may dial a first number to complete a first connection (e.g., right channel) and dial a second number to complete a second connection (e.g., left channel), thus creating stereo sound through the two channels. The dialer  210  may include memory for storing numbers or dialing codes, and may include a user interface to facilitate user interaction. 
     A synchronization controller  212  may synchronize sound between two or more channels when sound is transmitted from multi-channel sources. For example, a first channel of sound (e.g., right channel) may be transmitted via a first twisted pair loop  206 ( 1 ) while a second channel of sound (e.g., left channel) may be transmitted via a second twisted pair loop  206 ( 2 ). When sound travels through the telephone network  204 , it may travel via any number of routes, each route varying in distance and/or transmission time. Therefore, the sound from the first channel may be received before the sound from the second channel. The synchronization controller  212  may delay the sound from one or more channels to provide a substantially synchronized output of the sound by a set of speakers. In some instances, the synchronization controller  212  may facilitate manual adjustment of the sound synchronization. In this case, the user may be presented with a control input such as a knob, fader, or screen representation of such a device. The control input may introduce delay proportional to the control input position into the left channel and/or the right channel. To improve the sound when the initial synchronization is audibly wrong, the user may simply adjust the control input in one direction or the other until the perceived sound quality has been maximized. Additionally or alternatively, the synchronization controller  212  may automatically synchronize the sound between channels, such as by comparing the sounds from each channel through known methods of synchronization. In brief, a digital signal processor may sample signals from the left and right channels, compare the signals for similar sounds in both channels, and use the time difference between the similar sounds to automatically adjust the delay for the appropriate channel. 
     The multi-channel telephone  202  may include a sound interface  214  (e.g., stereo plug and jack) to enable the connection of a sound reproduction system  216  to the multi-channel telephone. In some instances, the sound interface  214  may be a multi-channel port such as a stereo jack, Ethernet connection, universal serial bus (USB) connection for connecting a portable or fixed sound reproduction system, such as the sound reproduction system  216 , including speakers and/or microphones. In other instances, the multi-channel telephone  202  may include integrated speakers and/or microphones. 
     With continued reference to  FIG. 2 , the architecture  200  includes the illustrative multi-channel telephone  202  including the sound reproduction system  216  configured as a portable headset. As illustrated, the headset  216  may include a single microphone  218  to capture sound from a user and to provide an audio input to both the analog hybrid circuits  208 . In other instances, each analog hybrid circuit  208  may include one or more microphones for capturing sound for transmission through the telephone network  204 . The headset  216  may also be configured with speakers  220  including a left speaker  220 (L) and a right speaker  220 (R) in connection to the left AHC  208 (L) and right AHC  208 (R), respectively. The speakers  220  provide multi-channel sound providing a spatial aural presentation of sound captured by a speaker. In some instances, the speakers  220  and/or microphones  218  may be connected to the multi-channel telephone via a first wireless connection  222  (e.g., Wi-Fi, Bluetooth, etc.). 
     As previously mentioned, the multi-channel telephone  202  is in connection with the telephone network  204 . In some instances, the multi-channel telephone  202  may be coupled to the telephone network  204  via a second wireless connection  224 . For example, the multi-channel telephone  202  may connect to the telephone network  204  via a wireless telephone network (e.g., Global System for Mobile communication (GSM), General Packet Radio Service (GPRS), Universal Mobile Telecommunications System (UMTS), etc.), Wi-Fi, or any other wireless protocol. In some instances, the multi-channel telephone  202  may be connected to the telephone network  204  via a wired system such as by a twisted pair, coaxial cable, shielded audio cable, power line carrier, or other wired connection. 
       FIG. 3  is a block diagram of an illustrative architecture  300  of an advanced multi-channel telephony system. The architecture  300  includes a multi-channel telephone  302  in connection with a telephone network  304 . The telephone network  304  may include a multi-channel transport path  306 , such as a time-division multiplexed (TDM) or a channelized internet protocol connection. In some instances, the telephone network  304  may include, in whole or in part, a packet network such as voice-over-internet protocol (VoIP) network. 
     The multi-channel telephone  302  may include an Internet protocol (IP) processor  308  to process the signals to or from the multi-channel transport path  306 . The IP processor  308  is operably connected to an audio processor  310 . The audio processor  310  facilitates transmitting and/or receiving sound to or from speakers  312  and microphones  314 , respectively. For example, the audio processor  310  may receive sound from the microphones  314  in multi-channel format, and process the sound for multi-channel transmission to the IP processor  308 , which in turn processes the signals for multi-channel transmission via the multi-channel transport path  306 . 
       FIG. 4  is an illustrative environment  400  including a multi-channel telephone  402  for providing multi-channel telephony according to an aspect of the disclosure. The multi-channel telephone  402  may include a number of inputs and outputs, collectively designated as a user interface  404 . The user interface  404  may include, without limitation, a series of input keys  406 , knobs  408  (e.g., for adjusting sound), and a numeric keypad  410  (e.g., configured for dialing telephone numbers or otherwise entering calling information). The multi-channel telephone  402  may also include a display  412  for presenting dialing and/or caller information, among other related information. The display  412  and the input keys  406  may enable a menu driven system for initiating and maintaining multi-channel telephony communications. 
     In some aspects, the multi-channel telephone  402  may include integrated speakers  414  and/or microphones  416  thus enabling multi-channel telephony. Additionally or alternatively, the multi-channel telephone  402  may include one or more remote or satellite speakers and/or microphones. In the illustrated embodiment, the speakers  414  may enable two channel sound (i.e., right and left signals), or more channels including channel configurations commonly designated 2.1, 5.1, 7.1, or any other configuration, where the number to the left of the decimal indicates the number of mid-frequency to high frequency channels and the number to the right of the decimal indicates a low frequency channel. 
     In one aspect, the multi-channel telephone  402  may be a hand-held device equipped with two or more of the speakers  414  oriented to present multi-channel output to a user and may include two or more of the microphones  416  to receive a multi-channel signal for transmission via a telephone network, such as the telephone network  114  shown in  FIG. 1 . In other aspects, the multi-channel telephone  402  may be configured as a mobile telephone. For example, the multi-channel telephone  402  may be configured as a portable pocket sized mobile telephone configured to connect to peripheral devices  418  to facilitate multi-channel telephony. 
     The peripheral devices  418  may be in connection to the multi-channel telephone  402  via a wireless connection, as discussed above, using an antenna  420  or may be in connection via the sound interface  214  (e.g., stereo plug and jack, USB). The peripheral devices  418  may include one or more microphones  418 ( 1 ), speakers  418 ( 2 ), headsets  418 ( 3 ), and/or integrated sensory devices  418 (N), among other possible peripheral devices. For example, the integrated sensory devices  418 (N) may be a speaker or vibration-generating device mounted on a chair. In some instances, the headsets  418 ( 3 ) may include an around-ear clip headset or hearing aid that inserts at least partially into a user&#39;s ear. In addition, the headsets  418 ( 3 ) may include one or more microphones. 
     Operation 
       FIG. 5  is a flow diagram of an illustrative process  500  of communication using a multi-channel telephony system. The process  500  includes a block  502  where a numerical input or other identifier is provided to initiate (e.g., dial) the desired connection to another communication device. For example, a user may input two telephone numbers, each corresponding to a PSTN line, using the dialer  210  on the multi-channel telephone  202  that uses two PSTN lines. The numerical input or other identifier may also be automated, such as to enable a single entry to connect multiple PSTN lines. Similarly, a number may be stored in an address book, or other known methods of dialing may be used to connect the multi-channel telephone  202  to another communication device. In a multi-channel network, a single address may be used such as a telephone number, uniform resource locator (URL), internet protocol (IP) address, or other identifier. At a block  504 , the multi-channel telephone  202  may connect to a multi-channel network, such as a TDM network or a packet network. 
     At a block  506 , the multi-channel telephone  202  may complete a handshake, or other configuration process, to configure the channels between the transmitting multi-channel telephone (transmitter) and the receiving multi-channel telephone (receiver). In a multi-channel network, user-to-network signaling may be used to specify the parameters of the multi-channel call such as number of channels, encoding scheme, channel assignments. For example, the transmitter may be enabled to provide 5.1 multi-channel sound to a user while a receiver may only be enabled to provide two channel sound. Therefore, the transmitter and the receiver may undergo a dynamic configuration process to determine how to best render the sound with the available resources (e.g., map microphones from one device to speakers on the other device). Algorithms which contain well-understood rules for channel mapping may be used, or an exchange of signaling messages may be used to configure the devices to provide the maximum multi-channel sound possible for each device. A lower-count channel device may be capable of using a higher-count channel connection using analog or digital signal processing to emulate the higher-count signal. For example, a device with two channel headphones may be able to connect to a 5.1 channel network source, and through the use of digital signal processing, delay, echo, and equalization, present a signal to the headphones that the user will perceive with more “depth than the sound provided by a simple two channel mapping. Such channel mappings are known to those familiar with the design of multi-channel consumer audio systems. 
     In addition, the configuration process at the block  506  may include other configurations, such as processing sound quality for differences in network bandwidth, or other configurations to enable multi-channel telephony between the connecting devices. In some instances, the handshake may recognize the presence of a multi-channel capable device, such as the device  202 , and, thus, connect the device in accordance with an established protocol. 
     At a block  508 , the process  500  may synchronize the channels to account for any time delay in one or more channels. The sound may be further adjusted at a block  510 , such as to change the tone or timbre of the sound, including volume, balance, or other aspects of the sound. The sound may also be enhanced at the block  510 , either manually or automatically, such as by incorporating an aural-exciter or other sound enhancing techniques. 
     At the block  512 , the process  500  may facilitate activation of multi-channel sound or monaural sound. For example, the multi-channel telephone  202  may be configured to switch between multi-channel sound and monaural sound (single channel sound) based on a user preference, subscription, or other determining factor. The switch may be initiated using a manual or automatic process. For example, if a network management system detects a heavy traffic load, the network may free up bandwidth by broadcasting a control signal to terminal devices to reduce network demand. One means of accomplishing such a reduction would be to reduce a multi-channel call to a single channel or monaural call. 
     Also, any of the acts described above with respect to the method  500  may be implemented by a processor or other computing device based on instructions stored on one or more computer-readable media associated with a multi-channel telephony system. Computer-readable media can be any available media that can be accessed locally or remotely by a multi-channel telephony system. By way of example, and not limitation, computer-readable media may comprise computer storage media such as volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer-readable instructions, data structures, program modules or other data. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can be accessed by a multi-channel telephony system. Combinations of the any of the above should also be included within the scope of computer-readable media. 
     Alternative Embodiments 
       FIG. 6  is a schematic of an alternative configuration of a multi-channel telephony system configured for a conference according to another aspect of the disclosure. A multi-channel telephone architecture  600  may include a plurality of speakers  602  and microphones  604  situated around a conference table or other conference area. In some instances, the multi-channel telephone may be integrated into a conference facilitating device, such as a table, a conference room, or the like. The multi-channel telephone architecture  600  may be used to connect to another multi-channel telephone at a second location to facilitate a multi-channel communication such as a conference call. Sound from users  606  may be captured by the microphones  604 , transmitted on separate channels, and emitted by one or more speakers in the second location. In an example, two similarly configured multi-channel telephones may be in connection between a first and second location. A first user  606 ( 1 ) at the first location may make a sound captured by a microphone  604 ( 1 ) which may in turn emit a sound on a speaker at the second location that is positioned similarly to a speaker  602 ( 1 ) at the first location. This configuration may result in a spatial aural presentation at the second location that mimics the user arrangement at the first location. 
       FIG. 7  is a schematic of another alternative configuration of a multi-channel telephony system including a multi-user headset configuration according to still another aspect of the disclosure. An environment  700  includes a multi-channel telephone  702  with a sound interface  704  for connecting a plurality of users  706 . At least a portion of the users  706  may have headphones  708  with speakers  710  and microphones  712 , however other configurations are contemplated. The speakers  710  and the microphones  712  are operably configured with the multi-channel telephone  702  (via wired or wireless connections). 
     The multi-channel telephone  702  is configured to receive and transmit multi-channel sound. For example, when a second user  706 ( 2 ) is speaking, a microphone  712 ( 2 ) may transmit a first channel sound while a microphone  712 ( 1 ) (situated near a user  706 ( 1 )) may transmit a second channel sound, thus exaggerating spatial separation of the users  706  and providing a spatial aural presentation to listeners using a multi-channel telephone, such as the multi-channel telephone  702 . 
     Conclusion 
     It is noted that the various modules shown herein may be implemented in hardware, software, or any combination thereof. Additionally, these modules are shown as separate items only for convenience of reference and description, and these representations do not limit possible implementations of the teachings herein. Instead, various functions described with these modules could be combined or separated as appropriate in a given implementation, without departing from the scope and spirit of the description herein. 
     Although techniques for providing multi-channel telephony have been described in language specific to certain features and methods, it is to be understood that the features defined in the appended claims are not necessarily limited to the specific features and methods described. Rather, the specific features and methods are disclosed as illustrative forms of implementing the claimed subject matter.