Telephone device

Abstract

PURPOSE: To provide a telephone device that can maintain a constant output level of sound output from a speaker in each speaker mode of a telephone device, regardless of manufacturing variations.CONSTITUTION: A telephone device according to the present invention includes a microphone that is installed on the telephone body and picks up sounds around the telephone body to obtain a picked-up signal, and a speaker amplifier that supplies a speaker drive signal that is an amplified speaker output signal to the speaker, and in speaker mode, a signal representing the call voice or a single-frequency tone is supplied to the speaker amplifier as the speaker output signal, and in test mode, a test tone signal is supplied to the speaker amplifier as the speaker output signal while adjusting the gain of the speaker amplifier on the basis of the amplitude of the picked-up signal and a predetermined reference value.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a telephone device having a function of outputting a call voice from a speaker. [Background technology]

[0002] Conventionally, telephones are configured so that the volume of a call voice and the sound source of a ring tone can be changed by a user's change operation. As such a telephone, for example, a telephone that allows the volume of a dial tone, which does not require a high volume, and the volume during a call, which requires a high volume, to be set separately is known (for example, see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2013-9084 A Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, the output level of the speaker mounted on a telephone set having a function for outputting the voice of a call from the speaker varies from product to product.

[0005] Therefore, even if the variation in the level of the electrical signal input to the speaker is suppressed, it is difficult to suppress the variation in the output level of the sound output from the speaker.

[0006] SUMMARY OF THE PRESENT EMBODIMENTS An object of the present invention is to provide a telephone device that can maintain a constant output level of sound output from the speaker when in the speaker mode of each telephone device, regardless of manufacturing variations. [Means for solving the problem]

[0007] The telephone device of the present invention is a telephone device having a telephone body with a built-in speaker and a handset connected to the telephone body, and includes a microphone installed on the telephone body for picking up sounds around the telephone body to obtain a picked-up signal, a speaker amplifier for receiving a speaker output signal and supplying a speaker drive signal that is an amplified version of the speaker output signal to the speaker, and a control unit for supplying a signal representing a call voice or a single-frequency tone to the speaker amplifier as the speaker output signal in speaker mode, and the control unit adjusts the gain of the speaker amplifier based on the amplitude of the picked-up signal and a predetermined reference value while supplying a test tone signal to the speaker amplifier as the speaker output signal in test mode. Effect of the Invention

[0008] The telephone device of the present invention outputs a test tone from a speaker installed in the telephone body, and adjusts the gain of the speaker amplifier so that the amplitude of the signal picked up by a microphone installed in the telephone body of the test tone is equal to a predetermined reference value.

[0009] This makes it possible to make the output level of the sound output from the speaker of each telephone device in the speaker mode constant, regardless of manufacturing variations. [Brief description of the drawings]

[0010] [Figure 1] 1 is a block diagram showing a configuration of a telephone set 100 as a telephone device according to the present invention. [Diagram 2] 10 is a flowchart showing a procedure for speaker variation correction control. [Diagram 3] 10 is a flowchart showing a procedure for a rattle correction control. [Figure 4A] FIG. 11 is a diagram showing an example of frequency characteristics when a rattling sound occurs. [Figure 4B] FIG. 11 is a diagram showing an example of frequency characteristics when no rattling noise occurs. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] FIG. 1 is a block diagram showing the configuration of a telephone set 100 as a telephone device according to the present invention.

[0012] The telephone 100 is connected to an exchange 200 to which multiple telephones are connected. The telephone 100 receives the user's voice through the handset 110 and transmits it to the other party's telephone through the exchange 200, while outputting the other party's voice received through the exchange 200 from the handset 110 or a speaker.

[0013] As shown in FIG. 1, telephone set 100 includes a line interface unit 10, a lamp unit 11, an operation button unit 12, a display unit 13, an AD / DA conversion unit 14, a handset amplifier unit 15, a speaker amplifier 16, a speaker 17, a microphone amplifier 18 and a microphone 19.

[0014] The line interface unit 10 is connected to the exchange 200, and relays various signals between the exchange and the control unit 20, such as an off-hook signal, a dial tone, a dial signal, and a speech voice signal.

[0015] The lamp unit 11 includes lamps consisting of a plurality of LEDs (Light Emitting Diodes) or the like that indicate various states of the telephone set 100 by lighting, blinking, or turning off, and is set individually to a lighting, blinking, or turning off state according to instructions from the control unit 20.

[0016] The operation button section 12 has a number of buttons, such as numeric buttons, a multifunction button, and a speaker button, that instruct the operation of the telephone, and supplies the control section 20 with an operation signal representing the operation assigned to that button in response to pressing of that button.

[0017] The display unit 13 is, for example, a liquid crystal display, and displays the contents indicated by a display signal supplied from the control unit 20.

[0018] The AD (analog to digital) / DA (digital to analog) conversion unit 14 converts the digital call voice signal and dial tone signal supplied from the control unit 20 into an analog call voice signal and dial tone signal, respectively. At this time, the AD / DA conversion unit 14 supplies the converted analog call voice signal or dial tone signal as a call voice signal SV to the handset amplifier unit 15, and further supplies the converted analog call voice signal or dial tone signal, or a test tone signal (described later), to the speaker amplifier 16 as a speaker output signal SA.

[0019] In addition, the AD / DA conversion unit 14 converts the analog call voice signal RV supplied from the handset amplifier unit 15 and the analog picked-up sound signal RA supplied from the microphone amplifier 18 into a digital call voice signal and a digital picked-up sound signal, respectively, and supplies each to the control unit 20.

[0020] Handset amplifier unit 15 includes amplifiers 151 and 152 .

[0021] Amplifier 151 amplifies the analog call voice signal SV supplied from AD / DA conversion unit 14 with a gain indicated by gain designation signal G1 supplied from control unit 20, and supplies the resulting call voice signal to handset 110. Amplifier 152 amplifies the call voice signal supplied from handset 110 with a gain indicated by gain designation signal G2, and supplies the resulting signal to AD / DA conversion unit 14 as the above-mentioned call voice signal RV.

[0022] The speaker amplifier 16 amplifies the speaker output signal SA supplied from the AD / DA conversion unit 14 with a gain indicated by a gain designation signal G3 supplied from the control unit 20, and supplies the amplified speaker drive signal to the speaker 17.

[0023] The speaker 17 is built into the main body of the telephone set 100, and outputs a call voice or a dial tone based on a call voice signal or a dial tone signal in response to the above-mentioned speaker drive signal.

[0024] The microphone amplifier 18 amplifies the picked-up signal supplied from the microphone 19 with a gain indicated by a gain designation signal G4 supplied from the control unit 20, and supplies the amplified signal to the AD / DA conversion unit 14 as the picked-up signal RA.

[0025] The microphone 19 is installed on the main body of the telephone set 100, picks up sounds around the telephone set 100, converts the picked up sounds into electrical signals, and supplies the electrical signals to the microphone amplifier 18 as the picked up sounds signals.

[0026] The control unit 20 establishes a call with a telephone connected to the exchange 200 by performing the control necessary for telephone calls, such as calling, receiving a dial tone, making a call and answering, using the line interface unit 10, the AD / DA conversion unit 14, and the handset amplifier unit 15.

[0027] The control unit 20 includes a memory 21, a signal analysis unit 22, and a test tone generation unit .

[0028] The memory 21 is made of a non-volatile semiconductor memory, and has programs stored therein in advance, which are responsible for speaker variation correction control for correcting variations in the output sound pressure level of the speaker 17, and for rumble noise reduction control for reducing rumble noise of the speaker 17.

[0029] The signal analysis unit 22 performs frequency analysis of the collected signal, and generates analysis result data indicating the frequency characteristics of the collected signal and the type of sound indicated by the collected signal. The type of sound is, for example, an alarm sound including an off-hook sound (howler sound), or a single-frequency sound such as a dial tone. The signal analysis unit 22 also measures the amplitude of the collected signal, and generates amplitude data indicating the measured amplitude.

[0030] The test tone generating section 23 generates a test tone signal having a certain level and an audio waveform of a predetermined frequency.

[0031] The control unit 20 performs speaker variation correction control and buzzing sound reduction control in accordance with a program stored in the memory 21 .

[0032] The speaker variation correction control and the buzzing sound reduction control will be described in detail below.

[0033] [Speaker variation correction control] The speaker variation correction control is performed, for example, during a pre-shipment test of the telephone set 100. That is, during the pre-shipment test, when an inspector operates a specific button to specify a test mode that prompts the implementation of speaker variation correction, the control unit 20 performs speaker variation correction control according to a program stored in the memory 21 in response to the instruction for this test mode.

[0034] FIG. 2 is a flowchart showing the procedure of such speaker variation correction control.

[0035] 2, first, the control unit 20 supplies the test tone signal generated by the test tone generation unit 23 to the AD / DA conversion unit 14 (step S11). As a result, a speaker output signal SA representing the test tone signal is supplied to the speaker 17 via the speaker amplifier 16, and the test tone is output from the speaker 17 at a volume corresponding to the gain indicated by the gain designation signal G3.

[0036] Next, the control unit 20 takes in the picked-up signal collected by the microphone 19 via the AD / DA conversion unit 14 (step S12), and obtains amplitude data LV representing the amplitude of the picked-up signal by measuring the amplitude of the picked-up signal using the signal analysis unit 22 (step S13).

[0037] Next, the control unit 20 judges whether the amplitude indicated by the amplitude data LV is higher than a predetermined reference value Lref (step S14). If it is judged in step S14 that the amplitude is higher than the reference value Lref, the control unit 20 sets the gain designation signal G3 indicating a new gain obtained by subtracting a predetermined value Δg from the gain indicated by the gain designation signal G3 at the present time (step S15). That is, the volume of the sound output from the speaker 17 is thereby reduced by a predetermined amount.

[0038] On the other hand, if it is determined in step S14 that the amplitude indicated by the amplitude data LV is not higher than the reference value Lref, the control unit 20 determines whether or not the amplitude is lower than the reference value Lref (step S16). If it is determined in step S16 that the amplitude is lower than the reference value Lref, the control unit 20 sets a gain designation signal G3 indicating a new gain obtained by adding a predetermined value Δg to the gain currently indicated by the gain designation signal G3 (step S17). That is, the volume of the sound output from the speaker 17 is thereby increased by a predetermined amount.

[0039] After executing step S15 or S17, the control unit 20 returns to step S12 and executes the operations of steps S12 to S17 again.

[0040] During this time, if it is determined in step S16 that the amplitude indicated by the amplitude data LV is not lower than the reference value Lref, that is, if the amplitude is equal to the reference value Lref, the control unit 20 exits the speaker variation correction control routine shown in FIG. 2 and returns to executing the main control (not described).

[0041] 2, first, the control unit 20 outputs a test tone from the speaker 17 (S11), picks up the test tone with the microphone 19 in the telephone set 100 (S12), and measures the amplitude (LV) of the picked up test tone (S13). Then, the control unit 20 adjusts the gain (amplification) of the speaker amplifier 16 so that the measured amplitude (LV) is equal to a predetermined reference value (Lref) (S14 to S17). That is, if the amplitude (LV) of the picked-up signal picked up by the microphone 19 is larger than the reference value (Lref), the gain of the speaker amplifier 16 is set to be lowered (S15), and if it is smaller, the gain of the speaker amplifier 16 is set to be increased (S17).

[0042] This makes it possible to make the output level of the speaker 17 of each of the plurality of telephone sets 100 accommodated in the exchange 200 constant, even if there is manufacturing variation in the output sound pressure level of the speaker 17.

[0043] 2, the gain of speaker amplifier 16 is adjusted so that the amplitude of the picked-up test tone is equal to reference value Lref, but the amplitude of the picked-up test tone does not necessarily have to match reference value Lref. In other words, control unit 20 only needs to adjust the gain of speaker amplifier 16 so that the amplitude of the picked-up test tone falls within a predetermined range including reference value Lref.

[0044] In short, in the present invention, a telephone device having a telephone body (100) with a built-in speaker (17) and a handset (110) connected to the telephone body may include a microphone, a speaker amplifier, and a control unit as described below.

[0045] That is, the microphone (19) is installed on the telephone body and picks up surrounding sounds to obtain a picked-up sound signal (RA). The speaker amplifier (16) receives the speaker output signal (SA) and supplies an amplified speaker drive signal to the speaker (17). The control unit (20) supplies a signal representing a call voice or a single-frequency tone as the speaker output signal (SA) to the speaker amplifier (16) in the speaker mode, and supplies a test tone signal to the speaker amplifier as the speaker output signal in the test mode, while adjusting the gain (G3) of the speaker amplifier (16) based on the amplitude of the picked-up sound signal (RA) and a predetermined reference value (Lref).

[0046] However, if the output level of the speaker is high, the telephone structure may also cause an abnormal sound (rumble). In many cases, this can be suppressed by lowering the level of the speaker output signal SA input to the speaker 17, i.e., by lowering the volume.

[0047] However, speaker 17 may vary in output sound pressure level due to manufacturing variations, and even if the speaker output signal SA is at the same level, some telephones produce a buzzing sound and some do not. Therefore, if the amount of volume reduction is determined based on a telephone that produces a buzzing sound, the speaker volume of a telephone that does not produce a buzzing sound will be lower than necessary.

[0048] Therefore, it has been difficult to prevent the crackling sound by minimizing the reduction in the volume of the speaker 17.

[0049] In consideration of this, in telephone 100, during normal use of telephone 100 after shipment, when the telephone enters a so-called speaker mode in which call voice, dial tone, etc. are output from speaker 17, the following buzzing sound reduction control is performed.

[0050] [Buzzing sound reduction control] For example, during normal use of telephone 100, when a user presses the speaker button included in operation button section 12 of telephone 100 to enter speaker mode, control section 20 performs buzzing sound reduction control in accordance with a program stored in memory 21.

[0051] FIG. 3 is a flow chart showing the procedure of such a rattle correction control.

[0052] In FIG. 3, first, the control unit 20 takes in a sound signal collected by the microphone 19 via the AD / DA conversion unit 14 (step S21).

[0053] Next, the control unit 20 analyzes the picked-up signal by performing frequency analysis on the picked-up signal using the signal analysis unit 22, thereby obtaining analysis result data representing the frequency characteristics of the picked-up signal and the type of sound represented by the picked-up signal (step S22).

[0054] Next, the control unit 20 judges whether or not the sound indicated by the collected signal, that is, the sound output from the speaker 17, is a sound that is not subject to the buzzer judgment based on the analysis result data (step S23). Note that the sound that is not subject to the buzzer judgment is a sound that requires a volume higher than a predetermined volume, such as an alarm sound including an off-hook sound (howler sound).

[0055] If it is determined in step S23 that the sound indicated by the picked-up signal is not subject to the crackle detection, the control unit 20 sets the volume of the sound output from the speaker 17 to the normal volume by supplying a gain designation signal G3 indicating a gain corresponding to the normal volume to the speaker amplifier 16 (step S24).

[0056] After executing step S23, the control unit 20 repeatedly determines whether the user has pressed the speaker button again to turn the speaker mode off, until it determines that the speaker mode has turned off (step S25).

[0057] In addition, when it is determined in the above-mentioned step S23 that the sound indicated by the sound pickup signal is not a sound that is not subject to the buzzing judgment, the control unit 20 judges whether or not the sound indicated by the sound pickup signal is a single-frequency sound based on the analysis result data (step S26). That is, in step S26, the control unit 20 judges whether or not the sound output from the speaker 17 is a single-frequency sound such as a dial tone that is likely to cause buzzing.

[0058] If it is determined in step S26 that the sound indicated by the picked-up signal is a sound of a single frequency, the control unit 20 performs a buzzing sound detection process (step S27).

[0059] That is, in the buzzing detection process, the control unit 20 first searches for frequency components that have peaks in the output level other than the fundamental wave of a single-frequency tone and multiple harmonics of the fundamental wave as noise components from the frequency characteristics of the picked-up signal represented by the above-mentioned analysis result data. At this time, if there are no noise components in the frequency characteristics, the control unit 20 sets a buzzing determination flag indicating that the sound output from the speaker 17 does not have buzzing.

[0060] On the other hand, when there is a noise component that generates a peak in the output level other than the fundamental wave and multiple harmonics, the control unit 20 compares the peak level of the noise component with the peak level of a harmonic (hereinafter referred to as a higher-order harmonic) that is one step higher than the higher of a pair of harmonics that sandwich the noise component. As a result, when the peak level of the noise component is higher than the peak level of the higher-order harmonic, the control unit 20 sets a buzzing determination flag indicating that the sound output from the speaker 17 has a buzzing sound. On the other hand, when the peak level of the noise component is equal to or lower than the peak level of the higher-order harmonic, the control unit 20 sets a buzzing determination flag indicating that there is no buzzing sound.

[0061] For example, as in the frequency characteristics of the picked-up signal shown in FIG. 4A, when a noise component NW having a peak level higher than that of the third harmonic W3 is contained between the first harmonic W1 and the second harmonic W2 among the harmonics W1, W2, and W3 relative to the fundamental wave Wr, the control unit 20 determines that there is a buzzing sound and sets a buzzing determination flag indicating the presence of a buzzing sound.

[0062] On the other hand, for example, as shown in FIG. 4B, even if a noise component NW is included between the first harmonic W1 and the second harmonic W2, if its peak level is lower than the peak level of the third harmonic W3, the control unit 20 determines that there is no buzzing sound and sets a buzzing determination flag indicating the absence of buzzing sound.

[0063] After executing step S27, the control unit 20 judges whether or not there is a rattling sound by referring to the judgment flag (step S28), and if it is judged that there is a rattling sound, sets the volume of the speaker 17 to be reduced (step S29). That is, the control unit 20 sets the gain designation signal G3 indicating a new gain obtained by subtracting a predetermined value Δg from the gain indicated by the gain designation signal G3 at the present time.

[0064] Next, the control unit 20 determines whether or not the user has pressed the speaker button again to turn the speaker mode off (step S30).

[0065] Here, if it is determined in step S30 that the speaker mode is not off, or if it is determined in step S26 that the sound indicated by the picked-up signal is not a single-frequency sound, the control unit 20 returns to step S21 and again executes the series of operations in each of the steps described above.

[0066] During this time, if it is determined in step S28 that no rattling sound is present, the control unit 20 proceeds to execution of step S25 described above, and waits until the speaker mode is set to the off state.

[0067] In this way, when the sound output from the speaker 17 is a single-frequency sound that is likely to cause a buzzing sound such as a dial tone, a buzzing sound detection process (S27) is performed based on the sound signal picked up by the microphone 19, and the control unit 20 reduces the volume (S29) until it is determined that there is no buzzing sound (S28).

[0068] Then, when it is determined in step S25 or S30 that the speaker mode has been turned off, the control unit 20 leaves the rumble reduction control routine shown in FIG. 3 and returns to the execution of main control (not described).

[0069] Therefore, according to the buzzing reduction control shown in FIG. 3, when a buzzing sound occurs in telephone 100 in speaker mode, this is detected by telephone 100, and the volume is automatically reduced until the buzzing sound disappears.

[0070] Therefore, according to the telephone set 100, even if there is manufacturing variation in the output sound pressure level of the speaker 17, it is possible to minimize the reduction in the volume of the speaker 17 and prevent crackling sounds. [Explanation of symbols]

[0071] 16 Speaker amplifier 17 Speaker 19. Mike 20 Control section

Claims

1. A telephone device having a telephone body with a built-in speaker and a handset connected to the telephone body, A microphone installed on the telephone body, which picks up sounds around the telephone body and obtains a picked-up sound signal; a speaker amplifier that receives a speaker output signal and amplifies the speaker output signal to supply a speaker drive signal to the speaker; a control unit that supplies a signal representing a call voice or a single-frequency tone as the speaker output signal to the speaker amplifier in a speaker mode; The control unit, in a test mode, supplies a test tone signal to the speaker amplifier as the speaker output signal, while adjusting the gain of the speaker amplifier based on the amplitude of the picked-up signal and a predetermined reference value.

2. 2. The telephone device according to claim 1, wherein the control unit adjusts the gain of the speaker amplifier so that the amplitude of the picked-up sound signal becomes equal to the predetermined reference value.

3. The telephone device according to claim 1 or 2, characterized in that, when in the speaker mode and the single-frequency tone is output from the speaker, the control unit determines whether the sound output from the speaker contains a buzzing sound based on the picked-up signal, and if it determines that a buzzing sound is present, reduces the gain of the speaker amplifier.

4. The telephone device described in claim 3, characterized in that the control unit searches for frequency components that have peaks in output level other than the fundamental wave of the single-frequency tone and multiple harmonics of the fundamental wave as noise components from the frequency characteristics obtained by performing frequency analysis of the picked-up signal, and determines whether or not there is a buzzing sound based on the peak level of a higher-order harmonic that is one step higher than the higher harmonic of a pair of harmonics that sandwich the noise component and the peak level of the noise component.

5. 5. The telephone device according to claim 4, wherein the control unit determines that a crackling sound is present when a peak level of the noise component is higher than a peak level of the higher-order harmonic.

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