JP5870785B2 - COMMUNICATION DEVICE, SIGNAL PROCESSING PROGRAM, SIGNAL PROCESSING METHOD, AND COMMUNICATION SYSTEM - Google Patents

Description

The present invention relates to a communication device that performs voice communication, such as a mobile phone, and relates to a communication device that uses a microphone for voice input, a signal processing program, a signal processing method, and a communication system.

  In a voice call of a communication device such as a mobile phone, a microphone mounted on the device is used. In addition to the voice of the caller, ambient sound enters the microphone. Ambient sounds are noise for caller voice. This ambient sound is converted into an electrical signal together with the voice of the caller and reaches the communication destination.

With respect to such a voice call, it is known to perform processing for suppressing environmental noise by signal synthesis (for example, Patent Document 1). Further, it is known that a microphone that captures only environmental sound is provided, and the environmental sound is canceled from the sound by the environmental sound signal obtained by the microphone (for example, Patent Document 2).

International Publication No. 2006/046293 Japanese Patent Laid-Open No. 9-36940

  By the way, in a voice call at a place where a communication device is adjacent, a voice during a call of another communication device enters the microphone of the communication device. Such mixing of ambient sounds reduces the S / N ratio of the main audio signal. When this ambient sound is converted into an electrical signal and reaches the communication destination, the intelligibility of the voice at the communication destination is reduced. In this case, there is a disadvantage that the ambient sound is notified to the communication destination as information other than the speaker voice.

  If the speaker brings the microphone closer to the mouth, it will be possible to suppress ambient sounds to some extent. However, if the sensitivity of the microphone is high, picking up ambient sounds cannot be avoided. If the speaker increases the generated sound, the generated sound of the speakers in the vicinity tends to increase.

  When the voice during a call is transmitted as a part of a voice signal by another communication device to another call destination, privacy and security are impaired.

Accordingly, an object of the communication device, the signal processing program, the signal processing method, and the communication system according to the present disclosure is to reduce the influence of call voice by other communication devices during a call in view of the above problems.

In the configuration of the present disclosure, an audio signal during a call of another communication device is received by the communication unit by wireless communication. Triggered by the start of a voice call, the voice communication unit determines whether or not an unnecessary sound is included in the output signal of the microphone. If the unnecessary sound is included, communication during a call that exists in a range where wireless communication is possible Wireless communication is established with the apparatus, and the communication unit receives an audio signal of the communication apparatus. By using the audio signal received by the communication unit, the signal canceling unit cancels the audio signal on the other communication device side included in the output signal of the microphone.

  According to the configuration of the present disclosure, the following effects can be obtained.

  (1) Even if the voice of another communication device enters the microphone of the communication device during a call, the voice is canceled, so the influence of the voice of the call by the other communication device can be reduced, and the SN ratio of the call voice And intelligibility is increased.

  (2) It is possible to suppress call voice from reaching the communication destination of this communication device via the adjacent communication device, and privacy and security of the adjacent caller are protected.

(3) The sound level generated during a call can be suppressed, contributing to the reduction of environmental noise associated with the call.

It is a figure which shows an example of the communication apparatus which concerns on 1st Embodiment. It is a figure which shows an example of a communication system. It is a figure which shows an example of an audio | voice signal. It is a figure which shows an example of the phase inversion of an audio | voice, and a synthesis | combination. It is a flowchart which shows an example of an audio | voice suppression process. It is a figure which shows an example of the communication apparatus which concerns on 2nd Embodiment. It is a figure which shows an example of an audio | voice suppression function. It is a figure which shows an example of an audio | voice signal and an antiphase signal. It is a figure which shows an example of the signal processing of sound phase adjustment. It is a figure which shows an example of the relationship between the volume of a synthetic | combination signal, and a delay setting value. It is a figure which shows an example of a communication system. It is a flowchart which shows an example of an audio | voice suppression process. It is a flowchart which shows an example of the process sequence of reverse phase communication. It is a flowchart which shows an example of the process sequence of a sound phase adjustment. It is a figure which shows an example of the relationship between the volume of a synthetic | combination signal, and a delay setting value. It is a flowchart which shows an example of the process sequence of the mobile telephone of a BT communication destination. It is a figure which shows an example of the suppression process sequence of an audio | voice. It is a figure which shows an example of the change of the amplitude with respect to time passage of an audio | voice. It is a figure which shows an example of the communication system which concerns on 4th Embodiment. It is a flowchart which shows an example of the process sequence of reverse phase communication. It is a flowchart which shows an example of the process sequence of the communication apparatus of a communication destination. It is a figure which shows an example of the communication apparatus which concerns on other embodiment. It is a figure which shows the example which suppresses an audio | voice in one communication apparatus. It is a figure which shows the example which suppresses an audio | voice in a some communication apparatus. It is a figure which shows the other example of a communication apparatus. It is a flowchart which shows the other example of an audio | voice suppression process. It is a flowchart which shows the other example of the process sequence of the mobile telephone of BT communication destination. It is a figure which shows the other example of the suppression process sequence of an audio | voice.

  [First Embodiment]

  FIG. 1 shows a communication apparatus according to the first embodiment. FIG. 2 shows a communication system. The configuration illustrated in FIGS. 1 and 2 is an example, and the communication device, the signal processing program, the signal processing method, and the communication system according to the present disclosure are not limited to the configuration. In the embodiment of the present disclosure, sound is used as a term representing a sound, a term representing a voice, or a term representing a sound in which voice and sound are mixed. The sound in which the voice and the sound are mixed includes the case where the sound or the voice is partially present over time.

  The communication device 2 acquires an audio signal from another communication device 14 (FIG. 2) located in the vicinity. The communication device 2 uses the processing unit 4 to cancel and reduce the voice on the other communication device 14 side included in the output signal output from the microphone (microphone) 12 using the voice signal acquired from the other communication device 14. And offset. The communication devices 2 and 14 are, for example, telephone devices such as a mobile phone, a smartphone, and a fixed phone, a personal digital assistant (PDA) having a voice communication function, or a PC (personal computer) having a voice communication function. . The processing unit 4 is connected to the microphone 12. An output signal of the microphone 12 is input to the processing unit 4. The processing unit 4 receives an output signal from the microphone 12, that is, an input audio signal from the microphone 12 and an audio signal from another communication device 14 (FIG. 2), and outputs the audio output signal to the outside of the communication device 2. Output.

  The communication device 14 is another communication device arranged separately from the communication device 2, and includes a processing unit 17 including a communication unit 16 and a microphone 18. The communication unit 16 performs wireless communication with the communication unit 6 of the communication device 2 and transmits an audio signal. The microphone 12 and the microphone 18 are an example of a voice input device that inputs captured voice to a device connected to the microphone. The microphone 12 converts the captured sound into a sound signal and outputs the sound signal, and inputs the output signal to the processing unit 4 as input sound. The microphone 18 converts the captured sound into a sound signal and outputs the sound signal, and inputs the output signal to the processing unit 17 as input sound. In addition, in this embodiment and embodiment shown below, the example of near field communication is shown as an example of the wireless communication between communication parts. In this embodiment, an example in which the communication unit 16 performs near field communication with the communication unit 6 is shown. The scope of the present disclosure is not limited to short-range wireless communication, and may be other wireless communication.

  The communication unit 6 is an example of a communication unit, and includes, for example, a short-range wireless communication unit having a short-range wireless communication function, and includes, for example, a short-range wireless communication circuit. The communication unit 6 communicates with another communication device 14 by, for example, near field communication. The communication unit 6 detects the communication device 14 within a short range from the communication device 2, connects to the communication device 14, and acquires an audio signal from the communication device 14. The communication unit 6 outputs the audio signal from the communication device 14 to the signal canceling unit 10.

  The signal canceling unit 10 is an example of means for canceling a specific sound included in the sound signal. The signal canceling unit 10 acquires the input voice from the microphone 12 and the voice signal received from the communication device 14. The signal canceling unit 10 synthesizes the input voice and the voice signal after adjusting the phase of the voice input from the microphone 12, the voice signal received by the communication unit 6 from the communication device 14, or both voices. In synthesizing the input voice and the voice signal, the phase of either the input voice or the voice signal is inverted by 180 [degrees]. This phase inversion may be performed by the signal canceling unit 10 or the communication device 14 by forming an anti-phase generation function in the signal canceling unit 10 or the communication device 14. Since the input voice or the voice signal is inverted and synthesized, the voice signal can be canceled.

  The input sound from the microphone 12 includes the sound of the speaker SP1 (FIG. 2) who is emitting sound toward the microphone 12. The input sound from the microphone 12 includes the sound of a speaker SP2 (FIG. 2) other than the speaker SP1. In addition, the input sound from the microphone 12 includes an environmental sound that comes from the surrounding environment. In the voice communication of the speaker SP1, the voice of the speaker SP2 and the environmental sound are ambient sounds and unnecessary sounds (unnecessary sounds). The speaker SP1 is a user of the communication device 2, and is an operator who performs voice communication with the communication partner CP1 (FIG. 2) using the communication device 2, for example. The speaker SP2 is a user of the communication device 14, and is, for example, a surrounding operator who performs voice communication with the communication partner CP2 (FIG. 2) using the communication device 14 around the communication device 2. The speaker SP2 is uttering voice toward the communication device 14.

  When the speaker SP2 is performing voice communication using the communication device 14 around the communication device 2, the microphone 12 captures the voice of the speaker SP2. The input voice from the microphone 12 includes the voice of the speaker SP2 captured by the microphone 12. The signal canceling unit 10 cancels the voice of the speaker SP2 in the input voice from the microphone 12. That is, the signal canceling unit 10 adjusts the phase of the input voice from the microphone 12 or the voice from the surrounding communication device 14 so as to remove the voice of the speaker SP2 from the input voice from the microphone 12, and The SP2 voice is canceled.

  The communication unit 6 and the signal canceling unit 10 are configured using a processor such as a DSP (Digital Signal Processor) or a CPU (Central Processing Unit), for example. This processor is an example of sound processing means for performing sound processing, and executes the above-described functions based on a program incorporated in the processor.

  The communication device 2 and the communication device 14 illustrated in FIG. The communication device 2 and the communication device 14 are arranged in a range in which short-distance wireless communication is possible, and are short-range wirelessly connected by short-range wireless communication. The voice of the speaker SP2 is directly input to the communication device 14. The communication device 14 transmits the input sound to the communication partner CP2 and transmits it to the processing unit 4 by short-range wireless communication. The communication device 14 constitutes a first communication device, and the communication device 2 constitutes a second communication device.

  The microphone 12 connected to the processing unit 4 captures the voice of the speaker SP1 in addition to the voice of the speaker SP1. The processing unit 4 receives an audio signal from the communication device 14 and an audio signal from the microphone 12. The communication device 14 adjusts the input voice by the signal canceling unit 10 and transmits the voice to the communication partner CP1.

  Next, referring to FIG. FIG. 3A is a diagram illustrating an example of an audio signal from a microphone, and FIG. 3B is a diagram illustrating an example of an audio signal received by short-range wireless communication. 3A and 3B, the vertical axis represents the sound intensity (unit: db). The horizontal axis represents time. That is, in FIG. 3A and FIG. 3B, the time change of the sound intensity is represented. Note that the audio signal illustrated in FIG. 3 is an example, and the scope of the present disclosure is not limited to such an audio signal.

  The audio signal 20 shown in FIG. 3A corresponds to, for example, the input audio signal from the microphone 12 described above. In the voice sections 23 and 25, the voice of the speaker SP1 is captured. In the voice sections 22 and 24, the voice of the speaker SP2 is captured. While the voice of the speaker SP1 is directly captured by the microphone 12, the voice of the speaker SP2 is partially captured. Therefore, in the audio signal 20, the voice of the speaker SP1 shows higher intensity than the voice of the speaker SP2. The voice of the speaker SP2 is an unnecessary voice in the voice communication in the processing unit 4 or the communication device 2, that is, an unnecessary sound, and is a voice to be suppressed. Note that the voice sections 21, 22, 23, 24, and 25 include environmental sounds other than the voice of the speaker SP2.

  An audio signal 30 illustrated in FIG. 3B represents an audio signal from the communication device 14. In the voice sections 32 and 34, the voice of the speaker SP2 is captured. In the voice sections 31, 33, and 35, there is no utterance by the speaker SP2, and no or almost no voice is captured. The waveform of the voice section 22 corresponds to the waveform of the voice section 32 and represents that the microphone 12 and the communication device 14 capture the same voice. The waveform of the voice section 24 corresponds to the waveform of the voice section 34, and represents that the microphone 12 and the communication device 14 are capturing the same voice. Since time is required for signal processing, the waveform of the voice section 32 and the waveform of the voice section 34 are generated with a delay of time ΔD from the waveform of the voice section 22 and the waveform of the voice section 24, respectively.

  Next, FIG. 4 will be referred to regarding the phase inversion and synthesis of speech. 4A shows an example of an audio signal from a microphone, FIG. 4B shows an example of an audio signal received by short-range wireless communication, FIG. 4C shows an audio signal shown in FIG. 4B in reverse phase, FIG. 4D is a diagram illustrating an example of an output signal of synthesized speech. The vertical axis represents the sound intensity (unit: db). The horizontal axis represents time. Note that the phase inversion and synthesis illustrated in FIG. 4 are examples, and the scope of the present disclosure is not limited to such phase inversion and synthesis.

  The audio signal 20 shown in FIG. 4A and the audio signal 30 shown in FIG. 4B are the same as the audio signal 20 shown in FIG. 3A and the audio signal 30 shown in FIG. 3B, respectively. In the example shown in FIG. 4, an anti-phase signal obtained by inverting the phase of the audio signal from the communication device 14 by 180 [degrees] is used to suppress the voice of the speaker SP2. The reverse phase signal is generated from the audio signal from the communication device 14 by the reverse phase generation function provided in the signal cancellation unit 10. This antiphase signal is also an audio signal, and indicates, for example, antiphase audio.

  The antiphase signal 37 shown in FIG. 4C is an antiphase signal of the audio signal shown in FIG. 4B.

  The output signal 40 shown in FIG. 4D is obtained by synthesizing the audio signal 20 from the microphone 12 shown in FIG. 4A and the antiphase signal 37 shown in FIG. 4C. When combining these signals, for example, the phase of the audio signal 20 from the microphone 12 is adjusted. The phase is adjusted by, for example, delaying the audio signal from the microphone 12 in time so that the audio section 22 and the audio section 32 match and the audio section 24 and the audio section 34 match. The voice section 41 to the voice section 45 correspond to the voice section 21 to the voice section 25, respectively. In the voice sections 42 and 44, the voice of the speaker SP2 is filtered by the antiphase signal 37 and suppressed. Therefore, the voice generated by the speaker SP2 cannot be recognized. Since the phase is adjusted so that the speech of the speaker SP2 is muted most while adjusting the phase of the speech signal 20, the speech of the speaker SP2 can be stably suppressed.

  Next, FIG. 5 is referred to regarding the voice suppression processing. FIG. 5 is a flowchart illustrating an example of a voice suppression process. Note that the processing procedure illustrated in FIG. 5 is an example, and the scope of the present disclosure is not limited to such a processing procedure. This processing procedure is an example of the signal processing program and the signal processing method of the present disclosure, and the communication apparatus 2 of the present disclosure executes the processing or the method.

  This suppression process is executed by, for example, the processing unit 4 triggered by the start of a voice call.

  When the communication device 2 starts voice communication such as a telephone call, the processing unit 4 confirms whether or not the communication device 14 exists in the vicinity (S1). This confirmation is performed by short-range wireless communication using the communication unit 6, for example. If the communication device 14 does not exist in the short-range range in which short-range wireless communication is possible, it is determined that there is no communication device 14 (NO in S1), and this processing procedure ends. When the communication device 14 exists in the short distance range, it is determined that the communication device 14 is present (YES in S1), and it is determined whether the communication device 14 is in a voice call (S2). If the voice call is not in progress (NO in S2), this processing procedure is terminated. When a voice call is in progress (YES in S2), short-range wireless communication is started between the processing unit 4 and the communication device 14 (S3). When the short-range wireless communication is started, an audio signal is received from the communication device 14 by the communication unit 6 (S4). The signal canceling unit 10 adjusts the phase between the acquired antiphase signal of the audio signal and the audio signal input from the microphone 12, and synthesizes these signals to cancel the signal (S5).

  The processing unit 4 acquires the speech signal of the speaker SP2 from the surrounding communication device 14 to the surrounding communication device 14 by the short-range wireless communication, and suppresses the speech of the speaker SP2 captured by the microphone 12 based on the acquired speech signal. can do. Thereby, it is suppressed that the voice of the speaker SP2 is transmitted to the communication partner CP1 of the speaker SP1 during the communication of the communication device 2. That is, this suppression prevents the voice information emitted by the speaker SP2 from leaking to the communication partner CP1. For example, the processing unit 4 is mounted on the mobile phone in order to mute or suppress the sound of the surrounding mobile phone input through the microphone 12 during a call on the mobile phone. The processing unit 4 receives voice input from surrounding mobile phones by short-range wireless communication. Further, the processing unit 4 takes the reverse phase of the sound input from the surrounding mobile phone, and synthesizes the reverse phase of this sound with the surrounding sound input from the microphone 12 by the signal canceling unit 10, The composite phase is adjusted to mute or suppress. This adjustment suppresses leakage of information spoken by surrounding speakers to the communication partner during communication using the mobile phone.

  Since the processing unit 4 receives the voice signal of the speaker SP2 for the surrounding communication device 14 by short-range wireless communication, the processing unit 4 has a wide azimuth capable of receiving the voice signal and can efficiently receive the voice signal. Further, since the voice of the speaker SP2 is received and this voice is suppressed by the voice signal of the speaker SP2, the voice of the speaker SP2 can be efficiently suppressed.

[Second Embodiment]
FIG. 6 shows a communication apparatus according to the second embodiment. FIG. 7 shows the voice suppression function. The configuration or function illustrated in FIGS. 6 and 7 is an example, and the communication device, the signal processing program, the signal processing method, and the communication system of the present disclosure are not limited to such configuration or function. The same parts as those in FIGS. 1 and 2 are denoted by the same reference numerals.

  The communication device 2 shown in FIG. 6 is, for example, a telephone device such as a mobile phone or a fixed phone, a portable information terminal, or a PC, and has a voice communication function.

  The storage unit 102 is an example of a storage unit, and includes, for example, a ROM (Read Only Memory) 104 and a RAM (Random Access Memory) 106. The ROM 104 is a non-volatile memory, and is composed of, for example, a flash memory or an EEPROM (Electrically Erasable and Programmable Read Only Memory). The ROM 104 stores an OS (Operating System) and various programs, and is used for storing various data. The RAM 106 is a memory that can be accessed at high speed, and is used for temporary storage of data, for example.

  The processor 108 is an example of a control unit that controls the communication device 2, executes an OS and various programs stored in the storage unit 102, and performs a wireless communication function 132 (FIG. 7) and an antiphase audio communication function 134 (FIG. 7) and functions such as a key input processing function. The processor 108 performs control related to a voice call such as a voice input control function and a voice output control function together with a DSP (Digital Signal Processor) 110. That is, the processor 108 and the DSP 110 configure, for example, the processing unit 4 described above, and perform voice suppression. Note that the wireless communication function 132 is an example of a communication unit, configures a wireless communication unit, and performs communication with a communication destination by wireless communication, for example. The wireless communication function 132 transmits the output sound synthesized by wireless communication to the communication destination. The antiphase audio communication function 134 is an example of an audio communication function or an audio communication means for communicating an audio signal, and performs control for receiving an audio signal for making an antiphase from surrounding communication devices, for example.

  The DSP 110 is an example of a control unit that controls voice suppression. The DSP 110 is constituted by, for example, a microprocessor that processes a digital signal, and processes the digital signal at high speed. The DSP 110 performs processing such as generation of an antiphase signal and phase adjustment of an audio signal.

  The audio codec 112 is an example of a signal conversion unit that digitizes or analogizes a signal and compresses or expands the digital signal. The audio codec 112 converts the analog audio signal input from the microphone 12 into a digital audio signal, compresses the digital audio signal, and outputs the compressed audio data to the DSP 110. The audio codec 112 receives the compressed audio data from the DSP 110, expands the audio data, and converts it into an uncompressed audio signal. The audio codec 112 converts the expanded audio signal into an analog signal and outputs an analog audio signal. The audio data compressed by the audio codec 112 is used for wireless communication or short-range wireless communication, for example. The analog audio signal output from the audio codec 112 is amplified by, for example, the amplifier 114 and then output from the speaker 116 as audio. The audio codec 112 is constituted by, for example, a digital signal processor. In this case, the DSP 110 may be configured to include the audio codec 112. The DSP 110 and the audio codec 112 process signals by moving signals between the DSP 110 and the audio codec 112.

  The short-range wireless communication I / F (interface) 118 is an interface for short-range wireless communication. For example, the short-range wireless communication I / F (interface) 118 is connected to the antenna 120 for short-range wireless communication and performs short-range wireless communication via the antenna 120. . Short-range wireless communication includes communication conforming to the Bluetooth (registered trademark) standard, communication conforming to the Wi-Fi standard, and infrared communication.

  The wireless communication I / F (interface) 122 is an interface for wireless communication, and is connected to the antenna 124 for wireless communication, for example, and performs wireless communication via the antenna 124. This wireless communication is, for example, wireless communication via a wireless communication base station. In addition, it is only necessary to be able to perform voice communication with a communication partner existing in a place beyond a short distance. For example, a wireless communication is performed with a parent device or the like arranged at a short distance by short-range wireless communication, and the parent device communicates with a wired or wireless communication There may be.

  The key input unit 126 is an example of a data generation unit that generates data in response to an operation, and includes, for example, an operation input key, a keyboard, or a touch panel. The key input unit 126 includes, for example, a screen displaying keys and a pointing device such as a mouse or a movement key. The key input unit 126 operates the pointing device to select a key on the screen, and stores data. To generate. By operating the key input unit 126, the key input unit 126 generates input information.

  The display unit 128 is an example of a display unit that displays information, and includes, for example, various display devices such as a liquid crystal display and an organic EL (Electro Luminescence) display, and displays characters, numbers, symbols, symbol strings, and the like. .

  Next, FIG. 7 is referred about the audio | voice suppression function of a process part.

  The short-range wireless communication function 129 is an example of the communication unit 6. The short-range wireless communication function 129 communicates with other communication devices by, for example, short-range wireless communication. The short-range wireless communication function 129 detects the communication device 14 within a short range from the communication device 2, connects to the communication device 14, and acquires an audio signal from the communication device 14. The near field communication function 129 outputs the sound from the communication device 14 to the antiphase generation function 130 based on the acquired sound signal.

  The inverse phase generation function 130 is an example of a phase inversion unit that inverts the phase of an input signal, and constitutes a phase inversion unit. In the anti-phase generation function 130, an anti-phase signal of the input signal is generated. That is, the anti-phase generation function 130 is also an anti-phase generation unit that generates an anti-phase signal of the input signal, and constitutes an anti-phase generation unit, for example, an anti-phase generation circuit. For example, the anti-phase generation function 130 inverts the phase of the signal by 180 [degrees] to generate an anti-phase signal. The reverse phase generation function 130 receives the audio signal from the communication device 14 from the short-range wireless communication function 129, inverts the phase of the audio signal from the communication device 14 by 180 degrees, and generates an antiphase signal. The reverse phase generation function 130 outputs this reverse phase signal to the sound phase adjustment function 131. The reverse phase generation function 130, together with the sound phase adjustment function 131, constitutes the signal canceling unit 10 described above. The antiphase signal is an audio signal whose phase is inverted by 180 [degrees] with respect to the audio signal received by the antiphase generation function 130, and represents, for example, antiphase audio.

  The sound phase adjustment function 131 includes a phase delay function 136, a phase synthesis function 138, and a level measurement function 140. The sound phase adjustment function 131 cancels, reduces, and cancels the voice on the other communication device 14 side included in the output signal output from the microphone 12 using the antiphase signal.

  The phase delay function 136 is an example of a delay unit that delays an audio signal, and includes, for example, a phase delay circuit. The phase delay function 136 receives an input audio signal from the microphone 12 and receives a delay setting value DV representing the amount of delay of the signal from the level measurement function 140. The phase delay function 136 delays the input audio signal based on the delay setting value DV. The delay set value DV is a variable and is adjusted according to the delay time ΔD of the antiphase signal with respect to the input audio signal from the microphone 12. This delay setting value DV is used as a coefficient for delaying the input audio signal from the microphone 12.

  The phase synthesizing function 138 is an example of a synthesizing unit that synthesizes signals, and is configured by a synthesizing circuit, for example. The phase synthesis function 138 synthesizes the anti-phase signal generated by the anti-phase generation function 130 with the input audio signal from the microphone 12 delayed by the phase delay function 136.

  The level measurement function 140 is an example of a measurement unit that measures the level of an audio signal, and includes, for example, a level measurement circuit. The level measurement function 140 measures the volume level of the synthesized audio signal output from the phase synthesis function 138 and adjusts the delay setting value DV so that the volume decreases.

  Next, FIG. 8 is referred with respect to an audio | voice signal and an antiphase signal. 8A is a diagram illustrating an example of an audio signal from a microphone, FIG. 8B is a diagram illustrating an example of an audio signal received by short-range wireless communication, and FIG. 8C is an antiphase signal of the audio signal received by short-range wireless communication. It is a figure which shows an example. The vertical axis represents the sound intensity (unit: db). The horizontal axis represents time. That is, in FIG. 8A, FIG. 8B, and FIG. 8C, the time change of the sound intensity is represented. Note that the audio signal and the antiphase signal shown in FIG. 3 are examples, and the communication device, the signal processing program, the signal processing method, and the communication system of the present disclosure are not limited to the audio signal and the antiphase signal. . The same parts as those in FIGS. 3 and 4 are denoted by the same reference numerals.

  The audio signal 20 shown in FIG. 8A, the audio signal 30 shown in FIG. 8B, and the antiphase signal 37 shown in FIG. 8C are the audio signal 20 shown in FIG. 3A (FIG. 4A) and the audio signal 30 shown in FIG. 3B (FIG. 4B), respectively. This is the same as the antiphase signal 37 shown in FIG. 4C. The inversion of the phase of the signal shown in FIG. 8B is processed at high speed by the DSP 110, for example. For this reason, the delay due to the process of inverting the phase is sufficiently small with respect to the time ΔD and ignored. Therefore, when synthesizing the audio signal 20 from the microphone shown in FIG. 8A and the antiphase signal 37 shown in FIG. 8C, the audio signal 20 from the microphone 12 is delayed by setting the time ΔD as the delay setting value DV.

  The sound phase adjustment function 131 shown in FIG. 9 receives the audio signal 20 from the microphone 12 shown in FIG. 8A and the antiphase signal 37 shown in FIG. 8C. In this case, the audio signal 20 is delayed by the phase delay function 136 and synthesized by the phase synthesis function 138 with the antiphase signal 37. The level measurement function 140 adjusts the delay setting value DV so that the volume of the synthesized signal is the smallest, and obtains a value ΔD as the delay setting value DV. The level measurement function 140 feeds back the obtained value ΔD to the phase delay function 136. As the delay set value DV, for example, at the first time, the delay time ΔD is sampled a plurality of times, and the average value is set to the estimated average value ΔD of the delay time. After setting the estimated average value, sampling of the delay time ΔD is continued, and the delay time ΔD is updated. By this update, the delay time ΔD is fed back.

  A curve 142 in the graph shown in FIG. 10 shows an example of the relationship between the volume of the combined signal and the delay setting value. In the curve 142, the volume of the combined signal becomes the minimum value at the time when the delay setting value corresponds to the phase ΔD, and the volume of the combined signal increases as the distance from the time corresponding to the phase ΔD increases. During the time corresponding to the phase ΔD, the antiphase signal 37 cancels out more sound, and the volume of the synthesized signal is the minimum value. Therefore, when the delay setting value is set to ΔD, it is possible to suppress the voice of the speaker who is speaking toward the providing communication device that provides the voice signal by the short-range wireless communication.

  Next, referring to FIG. 11 and FIG. FIG. 11 shows an example of a communication system. FIG. 12 is an example of a flowchart of a voice suppression process. The system illustrated in FIG. 11 and the processing procedure illustrated in FIG. 12 are examples, and the communication device, the signal processing program, the signal processing method, and the communication system of the present disclosure are not limited to the system and the processing procedure. . The processing procedure illustrated in FIG. 12 is an example of the signal processing program and the signal processing method of the present disclosure, and is executed by the processing unit 4 or the antiphase audio communication function 134 of the communication device 2 of the present disclosure. The same parts as those in FIGS. 1 and 2 are denoted by the same reference numerals.

  Around the communication device 2 shown in FIG. 11, for example, mobile phones 152-1, 152-2,..., 152-N exist as a plurality of communication devices (hereinafter, one or some mobile phones). Including the case of indicating a telephone, it is expressed as “mobile phone 152”). In this case, the antiphase audio communication function 134 searches the surrounding mobile phone 152 by short-range wireless communication when the call starts. When the mobile phone 152 exists in the surrounding area, short-range wireless communication with the surrounding mobile phone 152 is started. The reverse phase voice communication function 134 transmits a terminal call state inquiry to the mobile phone 152 of the short-range wireless communication destination. This inquiry about the terminal call state is, for example, an inquiry for inquiring whether a call is in progress or an inquiry for inquiring whether the terminal is on standby. When the surrounding mobile phone 152 is busy, reverse phase communication is performed. That is, an audio signal for making the phase opposite is received. Each mobile phone 152 is an example of the communication device 14, and the processing units 17-1, 17-2,..., 17-3 including the communication unit 16 and the microphones 18-1, 18-2,. , 18-N (hereinafter referred to as “microphone 18”, including the case where one or some microphones are shown).

  When a plurality of short-range communication request responses are received as a result of the search by short-range wireless communication, the antiphase audio communication function 134 establishes short-range communication with, for example, all the mobile phones 152 simultaneously or sequentially. . The antiphase audio communication function 134 receives the input level of the microphone 18 in the plurality of mobile phones 152 from the mobile phone 152. This input level is, for example, a past average value of the input level. The reverse phase audio communication function 134 determines in order from the mobile phone 152 having the highest input level whether the level of unnecessary sound related to the mobile phone 152 exceeds a predetermined threshold TL (FIG. 8A). The anti-phase audio communication function 134 performs anti-phase communication if the level of unnecessary sound exceeds the threshold value TL, and if not, the level of unnecessary sound related to the mobile phone 152 having the next highest input level sets the threshold value TL. Determine if it exceeds. Such a procedure is repeated.

  In the voice suppression processing procedure shown in FIG. 12, a mobile phone 152 that is one form of a terminal is illustrated as the surrounding communication device 14, and BT communication (Bluetooth (registered trademark) communication) is illustrated as short-range wireless communication. Yes. When a call is started in the communication device 2 equipped with the processing unit 4 (S101), the antiphase audio communication function 134 confirms whether there is an unnecessary sound (S102). The confirmation of the unnecessary sound is made, for example, from the sound waveform captured by the microphone 12. The voice from the microphone 12 has a difference in intensity between the voice of the speaker SP1 and the other voice with respect to the communication apparatus 2, and therefore, for example, whether or not there is a voice having a lower intensity than the voice of the speaker SP1 with respect to the communication apparatus 2 The presence or absence of unnecessary sound is determined by the above. In this case, it is determined, for example, from the waveform of the unnecessary sound whether the unnecessary sound is due to the voice of the speaker SP2 or the other environmental sound. Good. If there is no unnecessary sound (NO in S102), the confirmation is repeated, and if there is an unnecessary sound (YES in S102), it is confirmed whether there is a mobile phone 152 around the processing unit 4 or the communication device 2 (S103). When there is no mobile phone 152 in the surrounding area (NO in S103), confirmation of whether there is an unnecessary sound (S102) and confirmation of whether there is a mobile phone 152 in the surrounding area (S103) are repeated. If there is a mobile phone 152 in the surrounding area (YES in S103), the confirmed mobile phone 152 is requested to perform BT communication (S104). It is confirmed whether BT communication has been established (S105). If BT communication is not established (NO in S105), confirmation of establishment of BT communication is repeated. When the BT communication is established (YES in S105), the mobile phone 152 as the BT communication destination is inquired about the terminal call state (S106). Based on this inquiry, the reverse phase voice communication function 134 determines whether the mobile phone 152 of the BT communication destination is performing a voice call (S107). When the mobile phone 152 of the BT communication destination is in a voice call (YES in S107), it is confirmed whether the level of unnecessary sound exceeds the threshold TL (S108). If the mobile phone 152 of the BT communication destination is not in a voice call (NO in S107), since there is no voice input for the voice call to the mobile phone 152 of the BT communication destination, the unnecessary sound is confirmed (S102). Return and repeat the process. When there are a plurality of mobile phones 152 of the BT communication destination, for example, the input levels of the microphones 18 in the plurality of mobile phones 152 are received and confirmed, and the level of unnecessary sound is set to the threshold value TL in order from the mobile phone 152 having the higher input level. Check if it exceeds. When the level of the unnecessary sound exceeds the threshold TL (YES in S108), reverse phase communication is performed (S109), and the process is terminated. If the unnecessary sound level does not exceed the threshold TL (NO in S108), the confirmation of the unnecessary sound level is repeated.

  The processing procedure of the reverse phase communication shown in FIG. 13 is a subroutine of the reverse phase communication (S109) shown in FIG. In the processing procedure of the reverse phase communication, the reverse phase voice communication function 134 notifies “start of reverse phase communication” to the mobile phone 152 in communication with the BT communication destination (S121). By this notification, the microphone sound of the mobile phone 152 of the BT communication destination is received from the mobile phone 152 of the BT communication destination via the short-range wireless communication. The anti-phase audio communication function 134 activates the anti-phase generation function 130 (S122), activates the sound phase adjustment function 131 (S123), and the microphone of the mobile phone 152 that is the BT communication destination via the short-range wireless communication function 129. Reception of the audio signal is started (S124). The reception of the microphone audio signal is continued during the call of the communication device 2. When the call is finished, the anti-phase audio communication function 134 returns from the anti-phase communication process and ends the audio suppression process.

  After the reverse phase generation function 130 and the sound phase adjustment function 131 are activated, the reverse phase generation function 130 generates a reverse phase signal from the audio signal acquired by the short-range wireless communication function 129. The sound phase adjustment function 131 adjusts the phase and synthesizes the signal. The processing by the short-range wireless communication function 129, the reverse phase generation function 130, and the sound phase adjustment function 131 is continued during a call of the communication device 2.

  Next, FIG. 14 will be referred to regarding phase adjustment. FIG. 14 is a flowchart showing an example of a sound phase adjustment processing procedure. In this processing procedure, the delay set value DV is adjusted and determined. In this processing procedure, the sound phase adjustment function 131 synthesizes the input audio signal from the microphone 12 and the antiphase signal while shifting the phase of the input audio signal from the microphone 12 to obtain an output signal of the synthesized audio. The sound phase adjustment function 131 adjusts the delay setting value DV so that the volume of the output signal of the synthesized voice becomes the minimum volume.

  The sound phase adjustment function 131 sets the delay set value DV to 0 [milliseconds (msec)] as an initial state (S141), and measures the volume level of phase 0 (S142). The sound phase adjustment function 131 adds 1 [msec] to the delay set value DV and changes the delay set value DV = DV + 1 [msec] (S143), and measures the volume level of DV + 1 [msec] (S142). Then, it is determined whether the volume level has decreased (S145). If the volume level has decreased (YES in S145), the delay setting value DV is changed (S143), the volume level of the delay setting value DV after the change is measured (S144), and The determination of whether it has decreased (S145) is repeated. When the volume level does not decrease (NO in S145), that is, when the volume level is the same or increased, the sound phase adjustment function 131 subtracts 1 [msec] from the delay setting value DV, so that the delay setting value DV = DV−. The delay setting value DV is determined by changing to 1 [msec]. Then, the sound phase adjustment process ends.

  When the volume level of the audio output signal changes as shown by a curve 142 in FIG. 15, the volume level of the synthesized signal decreases as the delay setting value DV increases from the position of phase 0. When the delay set value DV reaches a time corresponding to the phase ΔD, the volume level starts to increase. Therefore, the delay set value DV is adjusted to the delay set value DV = ΔD.

  Next, FIG. 16 is referred with respect to the processing procedure of the mobile phone of the BT communication destination. FIG. 16 is a flowchart showing an example of the processing procedure of the mobile phone of the BT communication destination. This processing procedure is executed by, for example, the processing unit 17 as a processor of the mobile phone 152 of the BT communication destination. The processor of the mobile phone 152 that is the BT communication destination may have the same reverse phase voice communication function as the processing unit 4 and the communication device 2, and this reverse phase voice communication function may perform this processing procedure. When receiving the “terminal call state inquiry” request from the communication device 2 that is the BT communication destination device, the processor or the reverse phase voice communication function of the mobile phone 152 responds “busy” as the terminal call state. When the “reverse phase communication start” notification is received from the communication device 2 of the BT communication destination, after starting the “reverse phase generation unit” and “sound phase adjustment unit”, the transfer of the microphone sound to the BT communication destination is started.

  The mobile phone 152 of the BT communication destination determines whether or not a call is in progress (S161). If the call is not in progress (NO in S161), the confirmation is repeated. When a call is in progress (YES in S161) and there is no “terminal call state inquiry” (NO in S162), there is no “reverse phase communication start” notification (S164), so confirmation of “terminal call state inquiry” (S162) )repeat. If there is a “terminal call status inquiry” (YES in S162), a “calling” response is sent to the BT communication destination device as the terminal call status (S163). When there is a notification of “reverse phase communication start” (YES in S164), transfer of the microphone sound to the communication device 2 that is the BT communication destination is started (S165). The process ends. As a result, the processing unit 4 or the communication device 2, which is a BT communication destination device, receives an audio signal input to the microphone 18 of the mobile phone 152 through short-range wireless communication.

  Next, FIG. 17 is referred to regarding the sequence of the voice suppression process. FIG. 17 is a diagram illustrating an example of a speech suppression processing sequence. The sequence diagram illustrated in FIG. 17 is an example, and the communication device, the signal processing program, the signal processing method, and the communication system of the present disclosure are not limited to such a sequence.

  The communication device 2 shown in FIG. 17 is a mobile phone used by the speaker SP1, for example. Also, the mobile phone 152 shown in FIG. 17 is a mobile phone used by the speaker SP2, and has the same configuration as the communication device 2, for example. The mobile phone 152 includes a microphone 18, a short-range wireless communication function 156, an antiphase generation function 158, a sound phase adjustment function 160, and an antiphase audio communication function 162. The short-range wireless communication function 156 is an example of the communication unit 16. For example, the speaker SP1 is an operator who performs voice communication using the communication device 2, and the speaker SP2 is an operator who performs voice communication using the mobile phone 152, for example.

  In the communication device 2, when a call is started (S201), the reverse phase audio communication function 134 confirms whether there is an unnecessary sound (S202). If there is no unnecessary sound (NO in S202), the confirmation is repeated, and if there is an unnecessary sound (YES in S202), the surrounding mobile phone 152 is searched (S203). The reverse phase voice communication function 134 transmits a BT communication establishment request to the short-range wireless communication function 129 in order to request the confirmed mobile phone 152 to perform BT communication (S204). The short-range wireless communication function 129 transmits a BT communication request to the short-range wireless communication function 156 of the mobile phone 152 (S205). The transmission of the BT communication request establishes BT communication between the short-range wireless communication function 129 and the short-range wireless communication function 156 (S206).

  When BT communication is established, the reverse phase voice communication function 134 inquires of the reverse phase voice communication function 162 of the mobile phone 152 about the terminal call state (S207). In response to this inquiry, the reverse phase voice communication function 162 responds to the reverse phase voice communication function 134 of the communication apparatus 2 with “calling” as the terminal call state (S208). Based on this response, the antiphase audio communication function 134 determines whether the mobile phone 152 is engaged in an audio call (S209). If the mobile phone 152 is in a voice call (YES in S209), it is checked whether the level of unnecessary sound exceeds the threshold TL (S210). If the mobile phone 152 is not in a voice call (NO in S209), the process returns to the confirmation of unnecessary sound (S202) and the process is repeated. When the level of the unnecessary sound exceeds the threshold value TL (YES in S210), an antiphase communication start notification is transmitted to the antiphase audio communication function 162 (S211). Then, the antiphase audio communication function 134 activates the sound phase adjustment function 131 (S212), and activates the antiphase generation function 130 (S213). In the mobile phone 152, the voice of the speaker SP2 input to the microphone 18 is transmitted from the microphone 18 to the short-range wireless communication function 156 (S214). The short-range wireless communication function 156 transmits the voice signal of the speaker SP2 to the short-range wireless communication function 129 by BT communication (S215). The short-range wireless communication function 129 transmits the voice signal of the speaker SP2 to the antiphase generation function 130 (S216). The reverse phase generation function 130 converts the received voice signal of the speaker SP2 to the reverse phase, generates a reverse phase signal of the voice signal of the speaker SP2, and transmits it to the sound phase adjustment function 131 (S217). The sound phase adjustment function 131 attenuates the sound with the opposite phase by the sound phase adjustment (S218). If the unnecessary sound level does not exceed the threshold TL (NO in S210), the confirmation of the unnecessary sound level is repeated.

  With respect to the second embodiment described above, features, advantages, modifications, and the like are listed.

  (1) The communication device 2 acquires the voice signal of the speaker SP2 from the communication device 14 via the short-range wireless communication, and suppresses the voice of the speaker SP2 captured by the microphone 12 based on the acquired voice signal. Therefore, in the communication device 2, during the voice communication, the voice of the speaker SP2 is suppressed from being transmitted to the communication partner of the speaker SP1. The voice information emitted by the speaker SP2 is prevented from leaking to the communication partner of the speaker SP1.

  (2) In addition, since it is determined before short-range communication whether or not the voice captured by the microphone 12 includes unnecessary sound, short-range communication is suppressed when there is no unnecessary sound, and short-range communication is performed. It is possible to reduce the load on the processing unit 4 or the communication device 2 and the power consumption.

  (3) When there are a plurality of mobile phones 152 around the communication device 2, the level of unnecessary sound is judged in order from the mobile phone 152 having the highest input level. Can be done efficiently.

[Third Embodiment]
In the third embodiment, the sound phase adjustment function 131 adjusts the above-described phase and adjusts the synthesis ratio of the input audio signal from the microphone and the audio signal from the surrounding communication devices. That is, the sound phase adjustment function 131 adjusts the sound intensity of at least one of the input sound signal from the microphone and the sound signal from the surrounding communication device so as to remove the sound of the surrounding speakers. The audio signal is synthesized. By adjusting the intensity of the sound together with the phase adjustment, it is possible to increase the suppression of the voices of surrounding speakers. Since other configurations are the same as those of the first embodiment or the second embodiment, the description thereof is omitted.

  FIG. 18 is referred to regarding the delay setting value and the speech synthesis ratio. FIG. 18 is a diagram illustrating an example of a change in amplitude over time of audio. FIG. 18A shows a change over time of the sound input to the microphone 12 of the communication device 2. FIG. 18B shows a change over time of the sound input to the microphone 18 of the mobile phone 152. The time changes shown in FIGS. 18A and 18B are time-flowed based on the time reference shown in FIG. 18C. 18A and 18B is an example brought about by the voice of the speaker SP1 and the voice of the speaker SP2. For convenience, the amplitude change due to the speech signal of the speaker SP1 and the amplitude change due to the speech signal of the speaker SP2 are separately described separately. The changes shown in FIGS. 18A and 18B are examples, and the scope of the present disclosure is not limited to such changes.

  The voice signal 182-1 of the speaker SP1 confirmed between the times T1 and T3 in the communication device 2 is confirmed as the voice signal 182-2 of the speaker SP1 between the times T5 and T7 on the mobile phone 152. The voice signal 184-1 of the speaker SP1 confirmed between the times T10 and T12 in the communication device 2 is confirmed as the voice signal 184-2 of the speaker SP1 between the times T11 and T13 on the mobile phone 152. The voice signal 186-1 of the speaker SP2 confirmed in the mobile phone 152 between the times T2 and T4 is confirmed as the voice signal 186-2 of the speaker SP2 in the communication device 2 between the times T6 and T8. The voice signal 188-1 of the speaker SP2 confirmed in the mobile phone 152 between the times T9 and T12 is confirmed as the voice signal 188-2 of the speaker SP2 in the communication device 2 between the times T11 and T14. The voice signal 182-1 and the voice signal 182-2 of the speaker SP1 are signals having the same frequency. The voice signal 184-1 and the voice signal 184-2 of the speaker SP1 are signals having the same frequency. The voice signal 186-1 and the voice signal 186-2 of the speaker SP2 are signals having the same frequency. The voice signal 188-1 and the voice signal 188-2 of the speaker SP2 are signals having the same frequency.

  The audio signals 182-2, 184-2, 186-2, and 188-2 are delayed by a time ΔT due to the propagation of the audio, and the audio signals 182-1, 184-1, 186-1, and 188-1 due to the diffusion of the audio. The amplitude is smaller than The synthesis of the voice signal is determined based on, for example, the ratio of the amplitude of the voice signals 186-1 and 188-1 of the speaker SP2 in the mobile phone 152 and the amplitude of the voice signals 186-2 and 188-2 in the communication apparatus 2. The synthesis ratio is, for example, formula (1).

    Combining ratio = Amplitude in communication device / Amplitude in mobile phone (1)

Amplitude in communication device: Amplitude in input voice signal from microphone 12 Amplitude in mobile phone: Amplitude in voice signal received by short-range wireless communication

  The signal is synthesized based on, for example, Expression (2).

    Composite signal = Input audio signal from microphone + Composite ratio x Antiphase signal (2)

  The communication device 2 receives the audio signals 186-1, 182-2, 188-1, and 184-2 input to the microphone 18 by short-range wireless communication. The communication device 2 synthesizes the input audio signal from the microphone 12 and the antiphase signal based on the above-described phase adjustment and Expressions (1) and (2). If the resultant synthesized signal is output speech, the speech of the speaker SP2 can be efficiently suppressed.

  Since other configurations are the same as those in the first embodiment or the second embodiment, the description thereof is omitted.

  [Fourth Embodiment]

  In the fourth embodiment, a plurality of communication devices include a suppression device, and perform voice suppression in parallel in a plurality of communication devices connected by short-range wireless communication.

  Since the processing unit 4-1 and the processing unit 4-2 illustrated in FIG. 19 have the same configuration as the processing unit 4 of the first to third embodiments, description thereof is omitted. Since the communication device 2-1 and the communication device 2-2 illustrated in FIG. 19 have the same configuration as that of the communication device 2 of the first to third embodiments, description thereof is omitted. Since the microphone 12-1 and the microphone 12-2 shown in FIG. 19 have the same configuration as the microphone 12 of the first to third embodiments, description thereof is omitted.

  The processing unit 4-1 acquires an audio signal from the communication device 2-2 located in the vicinity by short-range wireless communication, and is input from the microphone 12-1 using the audio signal from the communication device 2-2. Suppresses surrounding sounds contained in the sound. The processing unit 4-2 acquires an audio signal from the communication device 2-1 located in the vicinity by short-range wireless communication, and is input from the microphone 12-2 using the audio signal from the communication device 2-1. Suppresses surrounding sounds contained in the sound.

  The processing unit 4-1 acquires the voice signal of the speaker SP <b> 2 for the surrounding communication device 2-2 from the surrounding communication device 2-2 via the short-range wireless communication, and the microphone 12-based on the obtained voice signal. The voice of the speaker SP2 captured by 1 can be suppressed. In the communication device 2-1 equipped with the processing unit 4-1, voice communication is performed between the speaker SP 1 and the communication partner CP 1 of the speaker SP 1. During this voice communication, the voice of the speaker SP2 is suppressed from being transmitted to the communication partner CP1. By this suppression, it is suppressed that the voice information emitted by the speaker SP2 leaks to the communication partner CP1 of the speaker SP1.

  In the processing unit 4-2, the voice signal of the speaker SP 1 for the surrounding communication device 2-1 is acquired from the surrounding communication device 2-1 through the short-range wireless communication, and the microphone 12-is based on the acquired voice signal. 2 can suppress the voice of the speaker SP1 captured. In the communication device 2-2 equipped with the processing unit 4-2, voice communication is performed between the speaker SP2 and the communication partner CP2 of the speaker SP2. During this voice communication, the voice of the speaker SP1 is suppressed from being transmitted to the communication partner CP2. By this suppression, it is possible to suppress the voice information emitted by the speaker SP1 from leaking to the communication partner CP2 of the speaker SP2.

  When performing voice suppression in parallel in a plurality of communication devices, for example, the processing unit 4-1 performs the processing procedure of the antiphase communication illustrated in FIG. 20. The reverse phase audio communication function 134 of the processing unit 4-1 notifies “communication start of reverse phase communication” to the communication device 2-2 during a call at the BT communication destination (S <b> 221). By this notification, for example, the microphone sound of the communication device 2-2 of the BT communication destination is received from the communication device 2-2 via the short-range wireless communication. The antiphase audio communication function 134 activates the antiphase generation function 130 (S222), activates the sound phase adjustment function 131 (S223), and transfers the sound of the microphone 12-1 to the communication device 2-2 of the BT communication destination. Is started (S224).

  The BT communication destination communication device 2-2 performs, for example, the processing procedure illustrated in FIG. The anti-phase audio communication function 134 of the communication device 2-2 of the BT communication destination determines whether or not a call is in progress (S261). If the call is not in progress (NO in S261), the confirmation is repeated. When a call is in progress (YES in S261) and there is no “terminal call state inquiry” (NO in S262), there is no “reverse phase communication start” notification (S263), so confirmation of “terminal call state inquiry” (S262) )repeat. When there is a “terminal call state inquiry” (YES in S262), a “calling” response is sent as a terminal call state to the communication device 2-1 at the BT communication destination (S264). When there is a notification of “reverse phase communication start” (YES in S263), the reverse phase audio communication function 134 activates the antiphase generation function 130 (S265), activates the sound phase adjustment function 131 (S266), and performs BT communication. The transfer of the sound of the microphone 12-2 is started to the previous communication device 2-1 (S267).

  When performing speech suppression in parallel in a plurality of communication devices, the processing unit 4-2 performs, for example, the reverse phase communication processing procedure illustrated in FIG. 20, and the communication device 2-1 performs, for example, the processing procedure illustrated in FIG. May be. Since other processing procedures are the same as those in the second embodiment, the description thereof is omitted.

  [Other Embodiments]

  In the above embodiment, the communication apparatus 2 is configured including the DSP 110 and the audio codec 112. However, for example, the functions of the DSP 110 and the audio codec 112 may be configured as separate circuits. 22 includes a short-range wireless communication unit 206, an antiphase generation unit 208, and a sound phase adjustment unit 210. The short-range wireless communication unit 206 is, for example, a circuit that forms the short-range wireless communication function 129, the anti-phase generation unit 208 is, for example, a circuit that forms the anti-phase generation function 130, and the sound phase adjustment unit 210 is, for example, a sound phase adjustment function 131 is a circuit constituting 131.

  The communication device 204 includes an AD conversion unit 212, encoders 214 and 218, decoders 216 and 220, a wireless reception unit 222, and a wireless transmission unit 224. The AD conversion unit 212 is a circuit that converts an analog signal into a digital signal. The analog signal is input from the microphone 12. The digital signal is output to the sound phase adjustment unit 210 and the encoder 214. The encoders 214 and 218 are circuits that encode a signal, and compress the signal, for example. The decoders 216 and 220 are circuits for decoding the encoded signal, and return the compressed signal to the original signal, for example. The wireless receiving unit 222 is a circuit that receives signals wirelessly via the antenna 120. The wireless transmission unit 224 is a circuit that transmits a signal wirelessly via the antenna 120. Since other configurations are the same as those of the above embodiment, the description thereof is omitted.

  Next, FIG. 23 is referred to regarding a configuration for suppressing voice in one communication apparatus. The communication devices 204-1 and 204-2 shown in FIG. 23 have the same configuration as the communication device 204 (FIG. 22). The arrows in the figure represent examples of voice or signal propagation. An arrow using a broken line represents an example of voice or signal propagation by surrounding speakers. Propagation of voice in which the voice of the speaker and the voices of surrounding speakers are superimposed is indicated by arrows using solid lines.

  The communication device 204-2 is arranged around the communication device 204-1. The speaker SP1 performs voice communication with the communication partner CP1 using the communication device 204-1. The communication partner CP1 asks the speaker SP1 "Tell me about Mr. D's address." When the speaker SP1 utters voice, the voice of the speaker SP1 is captured by the microphone 12-1, converted into a digital signal by the AD conversion unit 212-1, and then input to the sound phase adjustment unit 210-1. . The audio signal adjusted by the sound phase adjustment unit 210-1 is encoded by the encoder 218-1 and transmitted to the communication partner CP1 via the wireless transmission unit 224-1. The voice of the communication partner CP1 is received via the wireless reception unit 222-1, decoded by the decoder 220-1, and emitted from the speaker 116-1.

  The speaker SP2 performs voice communication with the communication partner CP2 using the communication device 204-2. The communication partner CP2 inquires of the speaker SP2 "Tell me your phone number." The speaker SP2 answers the communication partner CP2 as “090-11112222”. The voice of the speaker SP2 is captured by the microphone 12-2, converted into a digital signal by the AD converter 212-2, and then input to the encoder 218-2. The voice signal input to the encoder 218-2 is , Encoded by the encoder 218-2, and transmitted to the communication partner CP2 via the wireless transmission unit 224-2. The voice of the communication partner CP2 is received via the wireless reception unit 222-2, decoded by the decoder 220-2, and emitted from the speaker 116-2.

  The voice of the speaker SP2 is directly input to the microphone 12-2 of the communication device 204-2, and is also diffused into the space and input to the microphone 12-1 of the communication device 204-1. The sound input to the microphone 12-1 reaches the sound phase adjustment unit 210-1. Therefore, the voice of the speaker SP2 input to the microphone 12-2 is input from the AD conversion unit 212-2 to the encoder 214-2. The voice of the speaker SP2 is encoded by the encoder 214-2 and transmitted to the short-range wireless communication unit 206-1 via the short-range wireless communication unit 206-2. Near field communication is used for signal transmission between the near field communication unit 206-2 and the near field communication unit 206-1. The voice signal of the speaker SP2 received by the short-range wireless communication unit 206-1 is decoded by the decoder 216-1. An antiphase signal is generated from the audio signal decoded by the antiphase generation unit 208-1. The reverse phase signal reaches the sound phase adjustment unit 210-1, and the voice of the speaker SP2 input to the microphone 12-1 is suppressed. Thereby, the voice of the speaker SP2 is suppressed from being transmitted to the communication partner CP1, and the answer of the speaker SP2, that is, the telephone number of Mr. Y is prevented from leaking.

  Next, FIG. 24 is referred about the structure which suppresses an audio | voice in the communication apparatus 204-1 and the communication apparatus 204-2. The communication devices 204-1 and 204-2 illustrated in FIG. 24 have the same configuration as the communication devices 204-1 and 204-2 illustrated in FIG. The suppression of the voice of the speaker SP2 is the same as the case where the voice is suppressed in one communication apparatus shown in FIG. The arrows in the figure represent examples of voice or signal propagation. An arrow using a broken line represents an example of voice or signal propagation by surrounding speakers. Propagation of voice in which the voice of the speaker and the voices of surrounding speakers are superimposed is indicated by arrows using solid lines.

  In response to the inquiry of the communication partner CP1, the speaker SP1 replies, “We cannot give information about Mr. D”.

  The voice of the speaker SP1 is directly input to the microphone 12-1 of the communication device 204-1 and is also diffused into the space and input to the microphone 12-2 of the communication device 204-2. The sound input to the microphone 12-2 reaches the sound phase adjustment unit 210-2. The voice of the speaker SP1 input to the microphone 12-1 is input from the AD conversion unit 212-1 to the encoder 214-1. The voice of the speaker SP1 is encoded by the encoder 214-1 and transmitted to the short-range wireless communication unit 206-2 via the short-range wireless communication unit 206-1. Near field communication is used for signal transmission between the near field communication unit 206-2 and the near field communication unit 206-1. The voice signal of the speaker SP1 received by the short-range wireless communication unit 206-2 is decoded by the decoder 216-2. An antiphase signal is generated from the audio signal decoded by the antiphase generation unit 208-2. The reverse phase signal reaches the sound phase adjustment unit 210-2, and the speech of the speaker SP1 input to the microphone 12-2 is suppressed. Therefore, the voice of the speaker SP1 is suppressed from being transmitted to the communication partner CP2, and the answer of the speaker SP1 is prevented from leaking.

  With respect to the embodiment described above, the features and modifications thereof are listed below.

  (1) In the above embodiment, an embodiment is described in which the operator performs at the operator center or the like, but the present invention is not limited to this. Even when a plurality of people have a conversation using a portable terminal in a narrow range, it is possible to suppress the sounds of surrounding people.

  (2) In the above embodiment, the voices of the surrounding speakers are suppressed during voice communication by wireless communication. However, the present invention is not limited to this, and may be used for voice communication by wired communication. For example, a fixed telephone may be used as a communication device, and voice may be suppressed in voice communication through a telephone line network. Using a PC as a communication device, audio may be suppressed in network communication via a wired network such as the Internet. Furthermore, a communication device such as a handset phone or a headset may be connected to a fixed phone, a PC, or the like by a short-range wireless communication function and used as a communication device to suppress voice.

  (3) In the above embodiment, the audio signal received by the short-range wireless communication is converted to the opposite phase, but the present invention is not limited to this. For example, in the processing unit 4 illustrated in FIG. 25, input sound from the microphone 12 is input to the phase inverting unit 8. The phase inversion unit 8 converts the input sound from the microphone into an antiphase, and generates an antiphase signal. The signal canceling unit 10 synthesizes these signals by adjusting the phase or synthesis ratio between the antiphase signal and the audio signal from the surrounding communication device received from the communication unit 6 by the short-range wireless communication. Even with such a configuration, the effects described above can be obtained.

  (4) In the above embodiment, the reverse phase signal is generated on the communication device 2 side. However, for example, a phase inversion unit may be formed on the communication device 14 side or the mobile phone 152 side. In this case, the communication device 14 or the mobile phone 152 may invert the audio signal of the microphone 18 by the phase inverting unit and transmit the generated reverse phase signal to the communication device 2 via the communication unit 6. Even with such a configuration, the above-described effects can be obtained, and the processing load on the communication device 2 side can be reduced.

  (5) In order to suppress sound, sound signals may be received from a plurality of surrounding communication devices, and the sound may be suppressed by synthesizing a plurality of sound signals with the input sound from the microphone 12. When there are a plurality of communication devices in the vicinity, the voices of the speakers of these communication devices can be suppressed simultaneously.

  (6) The voice suppression processing procedure is not limited to the processing procedure described in the above embodiment, and may be other processing. For example, triggered by the start of a call, the reverse phase voice communication function 134 may perform the voice suppression processing procedure shown in FIG. In the voice suppression processing procedure shown in FIG. 26, the anti-phase voice communication function 134 confirms whether the mobile phone 152 is around the processing unit 4 or the communication device 2 (S301). If there is no mobile phone 152 in the surrounding area (NO in S301), the process is terminated. If there is a mobile phone 152 in the surrounding area (YES in S301), the confirmed mobile phone 152 is requested to perform BT communication (S302). It is confirmed whether BT communication has been established (S303). If BT communication has not been established (NO in S303), confirmation of establishment of BT communication is repeated. When the BT communication is established (YES in S303), the mobile phone 152 as the BT communication destination is inquired about the terminal call state (S304). Based on the response to this inquiry, the reverse phase voice communication function 134 determines whether the mobile phone 152 of the BT communication destination is in a voice call (S305). If the mobile phone 152 of the BT communication destination is in a voice call (YES in S305), after performing the above-described reverse phase communication (S306), the process is terminated and if the voice call is not in progress (NO in S305), The process ends. Since the processing ends when there is no mobile phone in the surroundings and when the mobile phone of the BT communication destination is in a voice call, the processing load on the processor is reduced.

  The processing procedure of the mobile phone of the BT communication destination is not limited to the processing procedure described in the above embodiment, and may be other processing. For example, in the processing procedure shown in FIG. 27, when there is no “terminal call state inquiry” (NO in S321), there is no “reverse phase communication start” notification (S323), and the mobile phone 152 of the communication destination ends this processing. To do. When there is a “terminal call status inquiry” (YES in S321), for example, “busy” or “standby” is returned as a terminal call status to the communication device of the BT communication destination (S322). When there is a notification of “reverse phase communication start” (YES in S323), the reverse phase audio communication function 134 activates the reverse phase generation function 130 (S324), activates the sound phase adjustment function 131 (S325), and Transfer of the voice to the communication device of the BT communication destination is started (S325). “Standby” means a state waiting for an incoming call.

  In this case, in the communication device 2 shown in FIG. 28, when a call is started (S341), the antiphase audio communication function 134 transmits a BT communication establishment request to the short-range wireless communication function 129 (S342). The short-range wireless communication function 129 transmits a BT communication request to the short-range wireless communication function 156 of the mobile phone 152 (S343). The transmission of the BT communication request establishes BT communication between the short-range wireless communication function 129 and the short-range wireless communication function 156 (S344). When the BT communication is established, the reverse phase voice communication function 134 inquires of the reverse phase voice communication function 162 of the mobile phone 152 about the terminal call state (S345). In response to this inquiry, the reverse phase voice communication function 162 responds to the reverse phase voice communication function 134 of the communication device 2 as a terminal call state, for example, “busy” (S346). Based on this response, the reverse phase voice communication function 134 determines whether the mobile phone 152 is in a voice call (S347). When the mobile phone 152 is in a voice call, a reverse phase communication start notification is transmitted to the reverse phase voice communication function 162 (S348). Then, the antiphase audio communication function 134 activates the sound phase adjustment function 131 (S349), and activates the antiphase generation function 130 (S350). The antiphase audio communication function 162 receives the antiphase communication start notification, activates the sound phase adjustment function 160 (S351), and activates the antiphase generation function 158 (S352). In the mobile phone 152, the voice of the speaker SP2 input to the microphone 18 is transmitted from the microphone 18 to the short-range wireless communication function 156 (S353). The short-range wireless communication function 156 transmits the voice signal of the speaker SP2 to the short-range wireless communication function 129 by BT communication (S354). The short-range wireless communication function 129 transmits the voice signal of the speaker SP2 to the antiphase generation function 130 (S355). The reverse phase generation function 130 generates a reverse phase signal of the speech signal of the speaker SP2 with the received speech signal of the speaker SP2 as an opposite phase, and transmits the signal to the sound phase adjustment function 131 (S356). The sound phase adjustment function 131 attenuates the sound with the opposite phase by the sound phase adjustment (S357).

  (7) In the above embodiment, an example of short-range wireless communication is shown as an example of wireless communication performed between communication devices. However, wireless communication performed between communication devices is not limited to short-range wireless communication. Absent. As the wireless communication, for example, an audio signal may be transmitted or received using another wireless communication such as a medium-range wireless communication or a long-range wireless communication.

As described above, the most preferable embodiment and the like of the present disclosure have been described. However, the communication device, the signal processing program, the signal processing method, and the communication system of the present disclosure are not limited to the above description. It goes without saying that various modifications and changes can be made by those skilled in the art based on the gist of the invention described in the scope of the present invention or disclosed in the specification, and such modifications and changes are included in the scope of the present invention. Needless to say.

2, 14, 204 Communication device 4, 17 Processing unit 6, 16 Communication unit 8 Phase inversion unit 10 Signal canceling unit 12, 18 Microphone 19 Communication system 102 Storage unit 108 Processor 110 DSP
112 Audio codec 118 Short-range wireless communication I / F
120, 124 Antenna 122 Wireless communication I / F
129, 156 Short-range wireless communication function 130, 158 Reverse phase generation function 131, 160 Sound phase adjustment function 132 Wireless communication function 134, 162 Reverse phase audio communication function 136 Phase delay function 138 Phase synthesis function 140 Level measurement function 152 Mobile phone 206 Short-range wireless communication unit 208 Reverse phase generation unit 210 Sound phase adjustment unit 212 AD conversion unit 214, 218 Encoder 216, 220 Decoder 222 Wireless reception unit 224 Wireless transmission unit

Claims (5)

A communication unit for receiving a voice signal during a call of the communication device by wireless communication from another communication device;
In response to the start of a voice call, it is determined whether or not an unnecessary sound is included in the output signal of the microphone, and when the unnecessary sound is included, the communication device and the wireless communication device that are in a range where wireless communication can be performed A voice communication unit that establishes communication and causes the communication unit to receive the voice signal of the communication device;
A signal canceller that cancels the audio signal of the communication apparatus included in the output signal of the microphone, by the audio signal received by the communication unit,
A communication apparatus comprising: A signal processing program for a communication device that performs signal processing using a computer,
With the start of a voice call as a trigger, it is determined whether or not an unnecessary sound is included in the output signal of the microphone, and when the unnecessary sound is included, another communication apparatus that is in a range where wireless communication can be performed and Establish wireless communication,
Is received by the communication unit an audio signal before Symbol communications device by wireless communication from the communication device,
The communication device side audio signal included in the output signal of the microphone is canceled by the signal canceling unit by the audio signal received by the communication unit,
A signal processing program for causing a computer to execute processing. With the start of a voice call as a trigger, it is determined whether or not an unnecessary sound is included in the output signal of the microphone, and when the unnecessary sound is included, another communication apparatus that is in a range where wireless communication can be performed and Establish wireless communication,
An audio signal in a call of the communication device acquired by wireless communication,
The audio signal of the communication apparatus side from the output signal of the microphone during a call, canceling by the audio signal acquired by radio communications,
And a signal processing method. A first communication device for transmitting a voice signal during a call by wireless communication;
In response to the start of a voice call, it is determined whether or not an unnecessary sound is included in the output signal of the microphone, and when the unnecessary sound is included, the first communication during a call that exists in a range where wireless communication is possible Establishing wireless communication with the apparatus, receiving the audio signal transmitted by the first communication apparatus, and transmitting the audio signal on the first communication apparatus side from the output signal of the microphone from the first communication apparatus A second communication device that cancels out the received audio signal;
A communication system comprising: The first communication device is
A phase inverting unit for inverting the phase before transmission of the audio signal;
A communication unit that transmits the audio signal with the phase inverted to the second communication device by wireless communication;
The communication system according to claim 4, comprising:

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