Patent Publication Number: US-2015087360-A1

Title: Apparatus and method for processing voice communication in mobile terminal

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) AND CLAIM OF PRIORITY 
     The present application is related to and claims priority under  35  U.S.C. §119(a) to a Korean Patent Application filed in the Korean Intellectual Property Office on Jan. 11, 2011 and assigned Serial No. 10-2011-0002606, the contents of which are incorporated herein by reference. 
     TECHNICAL FIELD OF THE INVENTION 
     The present invention relates to a mobile communication service and, in particular, to a device and method for processing voice communication service. 
     BACKGROUND OF THE INVENTION 
     Typically, a mobile terminal is designed to operate in one of the normal and speakerphone modes for voice communication. Here, the normal mode is the operation mode in which the user communicates by placing the mobile terminal near his/her ear, and the speakerphone mode is the operation mode in which the user communicates using the speakerphone while maintaining a distance from the mobile terminal. Recently, it is a trend that the mobile users tend to use smartphone which is provided with a relatively large display and a loudspeaker appropriate for supporting various multimedia functions. With the advance of communication and data processing technologies, the smartphone is evolving to communicate and process the high quality multimedia data such as high resolution video and audio data and, as the consequence, it is leading the improvement of the display and speakerphone performance so as to provide the user with crystal clear audio and video. 
       FIG. 1  illustrates a rear perspective view and a front view of a conventional mobile terminal. 
     As shown in  FIG. 1 , the conventional mobile terminal is provided with a pair of microphone MC 1  and speaker SP 1  at the bottom of the body and another pair of microphone MC 2  and receiver SP 2  at the top of the body. Here, the speaker SP 1  is the main speaker to output audio at high quality level in multimedia playback. In the above-structured mobile terminal, the voice communication can be progressed in one of the speakerphone mode and normal mode by switching between the auxiliary microphone MC 2  and the main microphone MC 1  using a switch in the codec. In this example, the normal mode is turned on with the activation of the receiver SP 2  at the top and the main microphone MC 1  at the bottom, and the speakerphone mode is turned on with the activation of the speaker SP 1  and the auxiliary microphone MC 2 . The reason why the conventional mobile terminal is equipped with two microphones and two speakers is that the closely arranged speaker and microphone cause echo. In order to avoid the echo caused by activating the speaker SP 1  and the main microphone MC 1  simultaneously, the auxiliary microphone MC 2  is enabled in pair with the speaker SP 1 . 
     For this reason, the conventional mobile terminal has been designed to have two microphones MC 1  and MC 2  and two speakers SP 1  and SP 2 . In case the mobile terminal uses the speaker SP 1  independently, it is necessary to have two microphones, one receiver speaker, and an independent speaker, resulting in requirement of additional parts such as microphone MC 2  and a Low Dropout (LDO) for supplying power to the microphone MC 2 . 
     SUMMARY OF THE INVENTION 
     To address the above-discussed deficiencies of the prior art, it is a primary object to implement a receiver serving as both the microphone and speaker, resulting in reduction of the number of parts and saving device mounting space of the mobile terminal supporting the normal and speakerphone modes. 
     In accordance with an aspect of the present disclosure, a mobile terminal device includes a microphone arranged at one end of a body of the device; a speaker arranged close to the microphone; a transceiver arranged at the other end of the body; a codec include a coder connected to the microphone, a decoder connected to the speaker, and a switch of which one node is connected to one of the coder and the decoder selectively and the other node is connected to the transceiver; and a communication controller which controls the switch to establish a path between the coder and the transceiver and enables the speaker in speakerphone mode. Preferably, the communication controller controls the switch to establish a path between the decoder and the transceiver and enables the microphone in normal mode. 
     In accordance with another aspect of the present disclosure, a communication service method of a mobile terminal includes checking current voice communication mode; establishing, when the current voice communication mode is speakerphone mode, an outgoing voice path between a coder and a transceiver and an incoming voice path to a speaker; processing signals in speakerphone mode, wherein the microphone and the speaker are arrange at one end of the terminal body close to each other, the transceiver is arranged at the other end of the terminal body, and the mobile terminal further includes a coder connected to the microphone, a decoder connected to the speaker, and a switch of which one node is connected to one of the coder and the decoder selectively and the other node is connected to the transceiver. Preferably, the communication service method further includes activating, when the current voice communication mode is normal mode, the normal mode by activating the incoming voice path between the decoder and the transceiver and the outgoing voice path by enabling the microphone. 
     Before undertaking the DETAILED DESCRIPTION OF THE INVENTION below, it may be advantageous to set forth definitions of certain words and phrases used throughout this patent document: the terms “include” and “comprise,” as well as derivatives thereof, mean inclusion without limitation; the term “or,” is inclusive, meaning and/or; the phrases “associated with” and “associated therewith,” as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, or the like; and the term “controller” means any device, system or part thereof that controls at least one operation, such a device may be implemented in hardware, firmware or software, or some combination of at least two of the same. It should be noted that the functionality associated with any particular controller may be centralized or distributed, whether locally or remotely. Definitions for certain words and phrases are provided throughout this patent document, those of ordinary skill in the art should understand that in many, if not most instances, such definitions apply to prior, as well as future uses of such defined words and phrases. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a more complete understanding of the present disclosure and its advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, in which like reference numerals represent like parts: 
         FIG. 1  illustrates a rear perspective view and a front view of a conventional mobile terminal; 
         FIG. 2  illustrates a rear perspective view and a front view of the mobile terminal according to the present disclosure; 
         FIG. 3  illustrates a configuration of the speakers and microphones of the mobile terminal according to the present disclosure; 
         FIG. 4  illustrates a configuration of the mobile terminal for supporting voice communication service according to the present disclosure; and 
         FIG. 5  illustrates a method for processing voice communication service in the mobile terminal according to the present disclosure. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIGS. 2 through 5 , discussed below, and the various embodiments used to describe the principles of the present disclosure in this patent document are by way of illustration only and should not be construed in any way to limit the scope of the disclosure. Those skilled in the art will understand that the principles of the present disclosure may be implemented in any suitably arranged mobile terminal. Exemplary embodiments of the present invention are described with reference to the accompanying drawings in detail. The same reference numbers are used throughout the drawings to refer to the same or like parts. Detailed descriptions of well-known functions and structures incorporated herein may be omitted to avoid obscuring the subject matter of the present invention. 
     Basically, the physical operations of the microphone and speaker are identical with each other. However, the speaker is responsible for converting the electric signal to the sound wave, and the microphone is responsible for converting the sound wave to the electric signal. In an embodiment of the present disclosure, the mobile terminal is equipped with a main microphone and a speaker at one side of the terminal body and a dual function microphone/speaker at the other side for supporting voice communication in both the normal mode and speakerphone mode. In an embodiment of the present disclosure, the mobile terminal includes a transceiver operating as both the microphone and speaker. In case the transceiver operates in microphone mode, the power is supplied to the transceiver to act as the microphone. In the microphone mode, the input voice is converted to the electric signal such that the electric signal is delivered to the coder via the switch in the codec. In case the transceiver operates in speaker mode, the electric signal output by the decoder is delivered to the transceiver via the switch such that the electric signal is converted to the original voice by the transceiver. 
     In the following, the description is directed to the example where the mobile terminal converts the audio signal to the voice signal. In the embodiments of the present disclosure, the audible audio signal such as voice and sound is referred to as voice signal. 
       FIG. 2  illustrates a rear perspective view and a front view of the mobile terminal according to the present disclosure. 
     Referring to  FIG. 2 , the mobile terminal according to an embodiment of the present disclosure includes a main microphone MC and a speaker SP installed at the bottom of the terminal body and a transceiver MS at the top of the terminal body. Here, the transceiver MS can be implemented with the same device as the receiver SP 2  of  FIG. 1 . Although not depicted in drawing, a controller controls a switch of the codec to establish the path for transferring the output of the transceiver MS to the coder of the codec when the transceiver is operating in microphone mode. The controller also controls the switch of the codec to establish the path for transferring the signal output by the decoder of the codec to the transceiver MS when the transceiver is operating in speaker mode. 
       FIG. 3  is a block diagram illustrating a configuration of the speakers and microphones of the mobile terminal according to the present disclosure. 
     Referring to  FIG. 3 , the speaker  160  as the main speaker (e.g., SP in  FIG. 2 ) and the microphone  150  as the main microphone (e.g., MC in  FIG. 2 ) are closely arranged at one end of the terminal body in longitudinal direction as depicted in  FIG. 2 . The transceiver  170  as the auxiliary microphone and speaker (e.g., MS in  FIG. 2 ) is arranged far from the speaker  160  and microphone  150  at the other end of the terminal body. The codec  100  includes a coder  110  for encoding the transmit voice signal, a decoder  120  for decoding the receive voice signal, and switches  130  to  145  for establishing transmit and receive voice paths in communication mode under the control of a controller (not shown). 
     In normal mode, the controller controls the switches  130  and  135  to establish the path from the decoder  120  to the transceiver  170  and cuts off the path from the transceiver  170  to the coder  110 . That is, the controller switches off the switch  130  and on the switch  135 . The controller also switches on the switch  140  to establish the path from the microphone  150  to the coder  110  and switches off switch  145  to cut the path from the decoder  120  to the speaker  160 . The controller also controls such that the power is supplied to the microphone  150  but not to the transceiver  170 . Accordingly, the microphone  150  converts the voice to the electric voice signal, which is sent to the encoder  110  via the switch  140  and encoded to be output. The receive voice signal is decoded by the decoder  120  and then sent to the transceiver  170  via the switch  135  such that the transceiver  170  converts the decoded voice signal into the voice. 
     In speakerphone mode, the controller controls the switches  130  and  135  to cut off the path from the decoder  120  to the transceiver  170  and establish the path from the transceiver  170  to the coder  110 . That is, the controller turns the switch  130  on and the switch  135  off. The controller also turns the switch  140  off to cut the path from the microphone  150  to the coder  110  and the switch  145  on to establish the path from the decoder  120  to the speaker  160 . Accordingly, the transceiver  170  converts the voice to the electric voice signal which is sent to the coder  110  and then output as encoded. The receive voice signal is decoded by the decoder  120  and then sent to the speaker  160  via the switch  145  so as to be converted by the speaker  160  and output in the form of audible sound wave. 
       FIG. 4  illustrates a configuration of the mobile terminal for supporting voice communication service according to the present disclosure. 
     Referring to  FIG. 4 , the communication unit  230  can include a Radio Frequency (RF) transmitter and an RF receiver. The RF transmitter is responsible for up-converting the transmit signal from a baseband to an RF band and amplifying the RF signal. The RF receiver is responsible for low noise amplifying the receive RF signal and down-converting the amplified signal from an RF band to a baseband. The communication unit  230  performs frequency up-converting and down-converting under the control of the controller  200 . The modem  220  includes a modulator and a demodulator to perform modulation on the transmit signal and demodulation on the receive signal under the control of the controller  200 . The modulator performs modulation on the transmit signal according to a predetermined modulation scheme (OFDM, CDM, GSM, etc.), and the demodulator performs demodulation on the receive signal to recover the original signal. 
     The codec  100  includes a coder  110  for encoding the transmit signal and a decoder  120  for decoding the receive signal. The codec  100  further includes a switch  180  for switching between the coder  110  and the decoder  120  to the transceiver  170 . The switch  180  establishes the output of the decoder  120  to the transceiver  170  in normal mode and the output of the transceiver  170  to the coder  110  in speakerphone mode under the control of the controller  200 . The input node of the coder  110  can be connected to the microphone  150  and the output node of the decoder  120  can be connected to the speaker  160 . 
     The memory  210  stores the operating system of the mobile terminal, programs for controlling the operations in the normal and speakerphone mode according to an embodiment of the present disclosure, and data produced as the result of the execution of the programs. The display  240  displays data processed in the mobile terminal, and the input unit  250  generates key data related to the commands for controlling the operations of the mobile terminal and alphanumeric data input. 
     The controller  200  controls the overall operations of the mobile terminal. Particularly in an embodiment of the present disclosure, the controller  200  controls the establishment and release of voice signal paths in the normal and speakerphone voice communication modes. Here, the voice communication modes include the outgoing call-making mode and incoming call-receiving mode. The voice call communication mode can be selected by the user through the input unit  250 . Here, the controller  200  can be a voice communication controller. 
     In the normal voice communication mode (also shortly referred to as normal mode), the controller  200  controls such that the driving power is supplied to the microphone  150  to establish the outgoing voice path from the microphone  150  to the coder  110 . Simultaneously, the controller  200  also controls the switch  180  (which can be the switches  130  and  135  of  FIG. 3 ) to establish the incoming voice path from the decoder  120  to the transceiver  170 . At this time, the path between the decoder  120  and the speaker  160  is cut off. In the normal mode, the voice input through the microphone  150  is delivered to the modulator of the modem  220  via the coder  110 , and the voice signal output by the demodulator of the modem  220  is delivered to the transceiver  170  so as to be output into form of audible sound wave (voice). 
     In the speakerphone voice communication mode (also shortly referred to as speakerphone mode), the controller  200  controls to supply driving power to the transceiver  170  and controls the switch  180  to establish the outgoing voice path from the transceiver  170  to the coder  110 . The controller  200  also controls to establish the incoming voice path from the decoder  120  to the speaker  160 . At this time the power supply to the microphone  150  is blocked, and the path between the microphone  150  and the coder  110  is cut off. Accordingly, in the speakerphone mode, the voice output by the transceiver  170  is delivered to the modulator of the modem  220  via the coder  110 , and the signal output by the demodulator of the modem  220  is delivered to the speaker via the decoder  120 , resulting in output of audible sound wave (voice). 
       FIG. 5  illustrates a method for processing voice communication service in the mobile terminal according to the present disclosure. 
     Referring to  FIG. 5 , the controller  200  monitors to detect an event and, if an even is detected, determines whether the event is a communication mode activation event such as incoming and outgoing calls ( 311 ). If the communication mode event is detected, the controller  200  determines whether the current communication mode is the normal mode or the speakerphone mode ( 313 ). The communication mode can be preset by the user through the input unit  250 . 
     If it is detected that the current communication mode is the speakerphone mode at step  313 , the controller  200  enables the speaker  160  and configures the transceiver  170  to operate as microphone ( 315 ). That is the controller  200  controls to supply the driving power to the transceiver  170  and controls the switch  180  to establish the outgoing voice path from the transceiver  170  to the coder  100 . The controller  200  also controls to establish the incoming voice path from the decoder  120  to the speaker  160  and block the voice path between the microphone  150  and the coder  110  at step  315 . In this state, the controller  200  processes the voice communication service in the speakerphone mode ( 317 ). In the speakerphone mode, the voice output by the transceiver  170  is delivered to the modulation of the modem  220  via the coder  110  and then the modulated voice signal is up-converted to the RF signal by the RF transmitter of the communication unit  230 . The RF signal received by the antenna is down-converted to the baseband voice signal by the RF receiver of the communication unit  230 , and the voice signal is demodulated by the demodulator of the modem  220  and then decoded by the decoder  120  so as to be output through the speaker  160  in the form of audible sound wave. If the communication ends in the speakerphone mode, the controller  200  detects the termination of the communication ( 319 ) and releases the communication session. 
     If it is detected that the current communication mode is the normal mode at step  313 , the controller  200  enables the microphone  150  and configures the transceiver  170  to operate as speaker ( 321 ). That is, the controller  200  supplies the driving power to the microphone  150  and controls to establish the outgoing voice path from the microphone  150  to the coder  110  and block the voice path between the speaker  160  and the decoder  120 . The controller  200  also controls the switch  180  to establish the incoming voice path from the decoder  120  to the transceiver  170  at step  321 . In this state, the controller  200  processes the voice communication service in the normal mode ( 323 ). In the normal mode, the voice input through the microphone  150  is transmitted via the coder  110  as described above, and the incoming voice signal is decoded b the decoder  120  and then converted by the transceiver  170  so as to be output in the form of audible sound wave. If the communication ends in the normal mode, the controller  200  detects the termination of the communication ( 325 ) and releases the communication session. 
     As described above, the mobile terminal is provide with the microphone  150  and the speaker  160  at one end of the terminal body in longitudinal direction and the transceiver  170  at the other end such that the transceiver  170  works as microphone or speaker by controlling the driving power to the LDO of the transceiver  170  and the internal switch  180  of the codec  100 . With this configuration, the microphone  150  at the bottom end and the transceiver  170  at the top end are enabled for supporting the normal mode voice communication while the speaker  160  at the bottom end and the transceiver  170  at the top end are enabled for supporting the speakerphone mode voice communication. That is, when the transceiver is working as microphone, the signal path is switched between the speaker and microphone by the switch  180  and the driving power is supplied to LDO. In this manner, the transceiver  170 , which is used as the receiver in the conventional mobile terminal, can be used as microphone. 
     As described above, the mobile terminal of the present disclosure is implemented with a main microphone and a speaker at one end and a transceiver working as microphone/speaker at the other end of the terminal body in longitudinal direction for supporting voice communication in both the normal and speakerphone modes, resulting in reduction of the number of parts and saving of device mounting space of the mobile terminal. 
     Although the present disclosure has been described with an exemplary embodiment, various changes and modifications may be suggested to one skilled in the art. It is intended that the present disclosure encompass such changes and modifications as fall within the scope of the appended claims.