JP2004221806A - Communication apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a communication apparatus which is provided with a circuit for detecting a distance between a user and a telephone set and detecting surrounding noise, and can automatically control sound volume adjustment and switching of an ear receiver and a speakerphone of the telephone set. <P>SOLUTION: The telephone set includes: a distance sensor 18 for sensing a distance between the user 8 and the telephone set 5; a noise detection microphone 19 for detecting noise around a receiver; and a circuit for optimizing a sound volume of the ear receiver 14 and the speakerphone 16 on the basis of noise level information detected by noise detection and automating switching from the ear receiver 14 to the speakerphone 16. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an ear receiver and a speakerphone provided for a cordless handset of a home cordless phone, a mobile phone, and the like, and relates to volume control during a call and a switching operation between the ear receiver and the speakerphone.
[0002]
[Prior art]
In conventional cordless telephones (slave units) and mobile phones, the user has to manually control the volume of the ear receiver and switch to the speakerphone during a call by using the operation buttons on the main body. These are cumbersome operations for beginners who are unfamiliar with the operation of telephones and for elderly users. Particularly in recent mobile phones, operations using soft keys have become mainstream, operation using devices has been different, and further operation requires skill. It is becoming like.
[0003]
On the other hand, Japanese Patent Application Laid-Open No. Hei 5-199289 discloses a technique for automatically controlling the volume according to the distance between the telephone and the user, thereby eliminating the above-mentioned inconvenience. . Japanese Patent Application Laid-Open No. Hei 5-167666 discloses a technique for switching from a normal handset to a microphone and a speaker when the output of the noise measuring means exceeds a predetermined level. Japanese Patent Application Laid-Open No. 5-83353 discloses a technique for adjusting the sound output of one of a receiver and a speaker selected in advance according to the output of the noise measuring means.
[0004]
[Patent Document 1]
JP-A-5-199289 [Patent Document 2]
Japanese Patent Application Laid-Open No. H5-167663 [Patent Document 3]
JP-A-5-83353
[Problems to be solved by the invention]
However, in the above-described conventional technology, only sound detection means is switched or sound volume is adjusted only by distance detection or only ambient noise, and the other one which has a large effect on audibility is not taken into consideration, and optimization of sound volume is insufficient. There was a problem that is.
[0006]
[Means for Solving the Problems]
In order to solve the above problem, a communication device of the present invention includes an ear receiver, a speakerphone having a larger volume generation capability than the ear receiver, and a distance detector that detects a distance between the ear receiver and a talker. Adjusting a volume of the ear receiver and / or the speakerphone based on the distance information detected by the distance detection unit and the ambient noise information detected by the noise detection unit. And a control unit.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described with reference to FIGS.
[0008]
FIG. 1 is a schematic configuration diagram of the present embodiment. The mobile phone according to the present embodiment includes an ear receiver 14 (receiver) used for a normal telephone call and a speaker phone 16 built in the mobile phone 5 as a sound generator. In the mobile phone according to the present embodiment, upon reception, the radio wave of the mobile phone network 9 is received by the antenna unit 10, and a call control unit is provided via a wireless signal processing unit 11 (hereinafter referred to as an RF unit) that performs reception processing, demodulation, and the like. A signal is sent to 12. At the time of calling, a voice signal of the user input from the microphone 15 is transmitted to the call control unit 12, further modulated into a transmission frequency by the RF unit 11, and transmitted from the antenna unit 10 to the mobile phone network 9. The call control unit 12 is connected to the numeral buttons 6 and the center cross button 7 for performing other operations, and performs operations such as setting of telephone functions, input of telephone numbers, adjustment of volume, and setting of ringtones. When the received sound is output from the ear receiver 14 or the speakerphone 16, the sound volume is set or a switching instruction is input. The mobile phone includes a distance detection circuit 17 and a distance sensor 18 for detecting a distance between the telephone body 5 and the user 8, and sends detected distance information to the call control unit 12. Further, in order to detect the surrounding noise level during a call, a noise detection microphone 19 for detecting surrounding noise and a noise detection circuit 41 are provided separately from the communication microphone 15. To be sent to. Based on the distance detection and the noise detection information, the volume of the ear receiver 14 and the speakerphone 16 can be controlled and automatically adjusted.
[0009]
Further, the detection indicator 44 is provided in an easily visible place of the main body, and the case where the distance detection is prioritized and the case where the noise detection is prioritized are displayed in different colors to indicate to the user how the detection is performed. It can be checked whether or not the volume setting has been performed.
[0010]
First, volume adjustment with priority on distance detection will be described. FIG. 2 shows a configuration of a distance detection unit centered on the distance detection circuit 17 and the distance sensor 18. The light emitting element 31 and the light receiving element 32 are built in the distance sensor section 18. The light emitting element 31 emits infrared light toward the user 8, and the light reflected from the user 8 is received by the light receiving element 32. The signal of the light intensity detected by the distance sensor 18 is sent to the distance detection circuit 17. The information sent here is converted into numerical data and sent to the call control unit 12. The call control unit 12 controls the volume of the ear receiver 14 and the speakerphone 16 connected thereto and controls the switching. For example, when the reflected light from the user 8 is strong, it is considered that the user 8 is near the mobile phone, and control is performed so that the volume of the ear receiver 14 and the speakerphone 16 is maintained at the current value (initial value). I do. Conversely, when the amount of reflected light is weak, it means that the user 8 is away from the telephone main body 5, and the volume of the ear receiver 14 is increased or the voice is switched to the speakerphone 16 to change the voice. To make it easier to hear. If it is determined that the distance is extremely large or if the distance cannot be detected, after detecting the distance for a certain period of time, the detection operation is stopped, the call is terminated, and a standby state is set. After the end of the call, the volume setting is returned to the initial state (for example, the speakerphone is off, and the volume of the ear receiver is a standard value).
[0011]
The mounting position of the distance sensor 18 is located at the center of the operation surface (front surface) of the mobile phone, as shown in FIG. 3, since the distance to the user is the easiest to measure and it is difficult to hide when held in the hand. In order to prevent a malfunction of the distance measurement, the irradiation angle is set to about 20 degrees in the up, down, left, and right directions. If this angle is too wide, infrared rays will be reflected to the users other than the user, and the accuracy of distance detection will be degraded.
[0012]
Next, a volume adjustment sequence based on distance detection by the distance sensor 18 will be described with reference to FIG. First, an initial setting is performed immediately after the start of a call (S1), and subsequently, a distance determination is performed (S2). The distance detected here is compared with a predetermined first threshold value L1 (S3). If the detected distance is small (S3-no), the detected volume is adjusted in steps of a predetermined level, for example, in steps of 2 dB step by step, for example, by 2 dB, and sound is emitted from the receiver phone 14 (S4). If the detected distance is larger than the threshold L1 (S3-yes), the detected distance is compared with a second threshold L2 (S5). If the detection distance is smaller than L2 (S5-no), the ear receiver 14 and the speakerphone 16 sound at a volume corresponding to the detection distance, respectively (S6). If the detection distance is longer than L2 (S5-yes), the sound generator is switched from the ear receiver to the speakerphone (S7). Further, the volume after the switching is adjusted to a volume that is easy for the user to hear in the same manner as in the case of the ear receiver (S8). After the adjustment of the volume, it is determined whether the call is the end or not (S9). If not, the difference between the volume and the previous time is detected (S10). It is determined whether the volume difference exceeds or does not exceed a predetermined threshold (S11). If not (S11-no), it is determined whether the detection interval is the maximum value or not (S13). If it is not the maximum (S13-no), the detection interval is increased (S14). If the difference in volume exceeds a predetermined threshold (S11-yes), the time interval for measuring the distance is returned to the initial value (S12). Alternatively, the measurement time interval is shortened by a predetermined amount. Thereafter, the process returns to the distance determination (S2) again, and the subsequent steps are repeated until the end of the call. After the end of the call, the volume setting of the telephone is set to the initial setting (for example, the speakerphone is off and the volume of the ear receiver is standard). In the above description, when the detection distance is between the threshold value L1 and the threshold value L2, the ear receiver 14 and the speakerphone 16 each set the sound volume by the same processing method as in the case of the single case, and sound is generated. Even if it fluctuates a little or the direction of the mobile phone and the user's ear deviates from the expected state, the user can hear clearly.
[0013]
Next, volume adjustment based on noise detection will be described. In general, a place where a mobile phone is used has a high usage rate in an environment where the surrounding noise is high, such as outdoors or in a transportation (car, train). Even if the sound volume can be heard sufficiently in a quiet room, there is a case where the sound pressure is low at the same volume setting in the place as described above and it is difficult to hear. When transmitting the contents of a telephone call to a plurality of parties, it is more convenient to switch from an ear speaker to a speaker phone. According to the present invention, it is possible to automatically set the volume when using in a place where ambient noise or a sound disturbing during a call is large, or when listening to the contents of a telephone call by a plurality of users.
[0014]
FIG. 5 is a block diagram illustrating the noise detection unit. The noise detection unit includes a noise detection microphone 19 that picks up noise, a band-pass filter 20 that controls the voice band of the noise, a band amplification circuit 43, and a noise detection circuit 41 that converts the noise level into numerical data. First, the signal flow will be described. The noise picked up by the noise detection microphone 19 is subjected to band correction by the band pass filter 20 and the band amplification circuit 43. This is to increase the sensitivity of noise detection by passing only a band (for example, 100 Hz to 1 kHz) that is easily perceived as noise during a call. Thereafter, the noise level is converted into numerical data by the noise detection circuit 41, and the numerical data is sent to the call control unit 12. The magnitude of the noise level is known from the input numerical data, and the volume of the ear receiver 14 and the speakerphone 16 connected to the call control unit 12 is adjusted according to the magnitude of the noise level. As shown in FIG. 6, the position of the noise detection microphone 19 is attached to the back of the telephone main body 5 so as to easily pick up ambient noise, and an omnidirectional microphone is used so that a wide range of noise can be picked up. Here, the band correction unit including the band-pass filter 20 and the band amplification circuit 43 will be described in detail. The voice band of the other party during a call generally has a bandwidth of 100 Hz to 3 kHz. This band is the most necessary band for a call, and the other bands are regarded as sounds (noise) not particularly required. For example, a frequency component under an environment where the noise of a vehicle is extremely high is often 500 Hz or less, and is passed through the bandpass filter 20 to be detected as a noise component. The band-corrected noise signal is transmitted from the band correction unit to the communication control circuit 12.
[0015]
Since the level of the band detected as the noise is amplified and sent to the noise detection circuit 41, the noise detection sensitivity can be increased. The noise detection circuit 41 converts the data into numerical data according to the noise level detected as described above, and the numerical data can adjust the volume of the ear receiver 14 and the speakerphone 16 connected to the call control unit 12.
[0016]
Next, a sequence of noise detection will be described with reference to FIG. When the mobile phone enters the talking state, first, various parameters are initialized (S21), and noise after a predetermined time from the start of the talking is detected (S22). The sound volume to be output from the sound generator is set based on the detected noise level (S23). The volume setting level is compared with a predetermined reference level A (S24). If the set volume level is lower than the reference level A, the ear receiver 14 is driven at the set level (S25). On the other hand, if the volume setting level is higher than the reference level A, a comparison is made with a reference value higher than the reference level A (referred to as level B) (S24). When the volume setting level is lower than the level B (S26-no), the ear receiver 14 and the speakerphone 16 are simultaneously driven with respective outputs corresponding to the setting level (S27). On the other hand, when the volume setting level is higher than the level B (S26-yes), the mode is switched to the speakerphone 16 (S28). When switching to the speakerphone 16, it is determined whether the input value corresponding to the sound generation level is larger or smaller than the allowable input of the speaker (S29). When the input is smaller than the allowable input (S29-no), the driving of the speakerphone 16 is continued at the set volume (S31), and when the input is equal to or higher than the allowable input (S29-yes), the speakerphone 16 is set to the maximum allowable value (S29-yes). S30) Continue driving the speakerphone 16 (S31). The above-described determination of the driving by the ear receiver 14 or the driving by the speakerphone 16 repeats the processing after the noise measurement (S22) until the end of the call (S32-no). yes), return the settings to the initial state.
[0017]
In the above noise detection, it is conceivable that the "voice" of a user who speaks during a call is erroneously detected as noise. However, in the present invention, this erroneous detection can be prevented by using the following means. I can do it. Means for distinguishing between a user's voice and ambient noise during a call will be described below. Generally, the noise is anxious only when the voice of the other party is being output from the ear receiver or the speakerphone during a call, that is, when the user is listening to the “voice” of the other party (at the time of receiving). Conversely, when the user speaks out a "voice" (at the time of transmission), he or she does not hear the other party's voice, so that the user does not notice much of the surrounding noise. For this reason, noise detection is performed only during reception, and voice transmission is not detected as noise unless performed during transmission. This will be described with reference to FIG. FIG. 9 shows a case in which the distance between the user and the telephone is short, for example, as shown in FIG. At the time of transmission, the input sound pressure of the communication microphone 15 is higher than the input sound pressure of the noise detection microphone 19. The sound pressure level comparison circuit 22 compares the sound pressure levels of the communication microphone 15 and the noise detection microphone 19, and outputs an "H" voltage when the communication microphone 15 is large. When the output of the sound pressure level comparison circuit 22 is "H", the noise detection 41 is turned "off", and the detection operation is performed only for distance detection. The volume adjustment of the ear receiver 14 and the speakerphone 16 connected to the call control circuit 12 is controlled by distance detection. As shown in FIG. 9, when the distance between the user's face and the telephone is short and the distance has not changed, the change in the volume does not occur, and the initial call volume is set. In the case where the distance between the user and the telephone is short and the telephone is receiving (listening to the other party), the noise detection microphone 19 is more intense than the sound pressure of the telephone microphone 15, as opposed to the above-described transmission. Therefore, the “L” voltage is output from the sound pressure level comparison circuit 22 and the noise detection 41 is turned “on”. At this time, the noise level input from the noise detection microphone is detected, and the sound volume is adjusted by the noise detection sequence described above with reference to FIG. As described above, the "H" or "L" voltage output from the sound pressure level comparison circuit 22 makes it possible to discriminate between the time of transmission and the time of reception, thereby preventing the above-described erroneous detection of noise. Can do things.
[0018]
Next, when the user talks at a position distant from the telephone body, it is difficult to distinguish between the voice of the user and the surrounding noise. In this case, only the distance information by the distance detection is detected, and the noise detection is set to “OFF”. As a means for performing only the distance detection, the “H” voltage is sent from the distance detection unit 18 to the noise detection unit 41 when the amount of change of the distance sensor 18 within a predetermined time exceeds a set reference value. The noise detection circuit 41 receiving “H” turns “off” as described above and does not perform noise detection. When the distance between the user and the telephone is greater than a predetermined distance, the speakerphone volume is set so as to be larger than the initial value by the above distance detection, so that the volume can be heard without performing volume adjustment by noise detection. It is adjusted to an easy state.
[0019]
Applying the operation of distance detection, for example, if you want to check the contents of a call with multiple users, by placing the phone body away from immediately after the start of the call, speakerphone switching by distance detection is performed The sound can be output from the speakerphone without operating the main unit.
[0020]
Further, a detection operation indicator 44 is provided at a prominent position of the telephone body 5 so that it is possible to know which detection means is currently used to adjust the volume. For example, "red" can be lit in color when detecting distance, and "orange" can be lit in color when noise is detected. As shown in FIG. 6, the noise detecting microphone 19 is installed on the back of the mobile phone (outside of the transmitter opposite to the operation surface), and a non-directional microphone is used as the detecting microphone. In the case of unidirectionality, accurate detection cannot be performed unless the back of the main body is directed in the direction of the noise source. This is because noise can be detected without turning the back face toward the noise source.
[0021]
It is preferable to provide the noise detection microphone 15 as described above in terms of measurement accuracy. However, when accuracy is not required, it is determined that the user is not speaking out of the input from the transmission microphone. By adopting a level below a predetermined level as a noise level, it is possible to use it as a noise detection unit.
[0022]
As described above, if the distance detection and the noise detection are separately performed, the error of the set value of the audio output tends to increase. Therefore, it is desirable to evaluate the two parameters simultaneously and set the necessary audio output. The audio output is set so as to satisfy the following conditions.
(1) The sound pressure when the sound emitted from the mobile phone reaches the user's ear is higher than the noise at the time of measurement by a predetermined level (dB) or more.
(2) The sound pressure when the sound emitted from the mobile phone reaches the user's ear is a predetermined level that is easy for ordinary people to listen to.
(3) It does not exceed the allowable maximum output of the sound generating means (ear laborer or speakerphone).
[0023]
According to the above principle, setting the voice output requires estimating the reduction in sound pressure due to the distance between the cellular phone sounding means and the user. It is sufficient to determine a relational expression that is inversely proportional to the square of, and to estimate the sound pressure of the sound sensed by the user's ear by the expression. A method of switching between the ear receiver and the speakerphone and adjusting the output based on the above-described concept will be described with reference to the flowchart of FIG.
[0024]
First, after a call is started, the mobile phone is set to an initial state (S31), and after a certain time, the distance between the mobile phone sounding means and the user and the ambient noise are measured (S32). The sound volume is set from the measured value (S33). The set sound volume is compared with a predetermined reference value C to determine whether the sound volume setting level is equal to or higher than the switching level C (S34). If the sound generation level is lower than the switching level C (S34-no), the ear receiver 14 is driven at the sound generation level. If the sound volume setting level is equal to or higher than the switching level C (S34-yes), a comparison is made with a level D higher than the level C. If the sound volume setting level is lower than the switching level D (S36-no), the ear receiver 14 and the speakerphone 16 are driven with respective outputs corresponding to the setting level (S37). If the sound volume setting level is higher than the switching level D (S36-yes), the mode is switched to the speakerphone (S38), and the sound volume setting level is compared with the allowable level of the speakerphone (S39). When the sound volume setting level is higher than the allowable level of the speakerphone (S39-yes), the sound volume setting level is set to an allowable maximum value (S41), and the speakerphone is driven (S40). If the sound volume setting level is lower than the allowable level of the speakerphone (S39-no), the speakerphone is driven at the sound volume setting level (S40).
[0025]
At the sound volume set as described above, the end of the call is determined while driving the ear receiver or the speakerphone is continued (S42). When the call is terminated (S42-yes), the setting is returned to the initial state and the call is terminated. If the call is continuing (S42-no), the difference between the current volume setting level and the previous volume setting level is further detected (S43). If the difference is smaller than the predetermined threshold value (S43-no), step S43 is performed. It is checked whether the time interval between the detection and the setting repetition starting from 32 is the maximum value (S46). When the repetition interval is the maximum value (S46-yes), the detection is continued at the same interval, and when the repetition interval is not the maximum value (S46-no), the interval is increased (S47). If it is larger than the predetermined threshold value (S44-yes) in the sound volume setting level difference determination (S44), the detection interval is set to the initial value (S45). At this time, the repetition interval may be shortened by a predetermined time. Thereafter, the process returns to the distance and noise determination (S32) described first, and the subsequent steps are repeated until the end of the call.
[0026]
According to the communication device of the embodiment, the distance measuring unit for detecting the distance between the user 8 and the telephone 5 and the noise detecting unit for detecting the ambient noise at the time of use are provided. By performing volume control and switching control of the ear receiver and the speakerphone, it is possible to improve call quality. In addition, the above-described operation of manually adjusting the call volume and switching to the speakerphone, which has been manually operated by the user, is automated, and the operability can be improved.
[0027]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to the communication apparatus of this invention, the call quality can be improved.
[Brief description of the drawings]
FIG. 1 is a block diagram of a communication device including a distance detection circuit and a noise detection circuit, which are features of an embodiment.
FIG. 2 is a block diagram illustrating a distance detection unit which is one of the features of the embodiment.
FIG. 3 is a diagram showing an installation position of a distance detection sensor, a detection indicator installation position, and the like, which are one of the features of the embodiment.
FIG. 4 is a flowchart illustrating a volume adjustment sequence based on distance detection, which is one of the features of the embodiment.
FIG. 5 is a block diagram showing a noise detection circuit as one of the features of the embodiment.
FIG. 6 is a diagram showing an installation position of a noise detection microphone which is one of the features of the embodiment.
FIG. 7 is a view showing a state in which the user is using the telephone body close to the telephone according to one of the embodiments.
FIG. 8 is a flowchart illustrating a volume adjustment sequence based on noise detection, which is one of the features of the embodiment.
FIG. 9 is a block diagram illustrating a method of adjusting a sound volume by distance detection and noise detection, which are features of the embodiment.
FIG. 10 is a flowchart in a case where volume adjustment, which is a feature of the embodiment, is performed by combining two methods of distance detection and noise detection.
[Explanation of symbols]
5: mobile phone body, 8: user, 9: mobile phone line network, 10: antenna,
11: RF unit, 12: communication control unit, 14: ear receiver,
15: microphone, 16: speakerphone, 17, distance detection circuit,
18: distance sensor, 19: noise detection microphone, 20: band limiting filter (band pass filter),
22: sound pressure comparison circuit, 23: transmission / reception switching circuit,
31: light emitting element, 32: light receiving element, 41: noise detection circuit,
43: band correction circuit, 44: detection operation indicator

Claims (4)

Ear receiver,
A speakerphone having a volume generation capability greater than the ear receiver,
A distance detection unit that detects the distance between the ear receiver and the caller,
A noise detector that detects ambient noise;
A control unit that adjusts the volume of the ear receiver and / or the speakerphone based on the distance information detected by the distance detection unit and the ambient noise information detected by the noise detection unit. Communication equipment. The communication device according to claim 1, wherein:
A communication device that switches to operate the ear receiver and / or the speakerphone based on distance information detected by the distance detection unit and ambient noise information detected by the noise detection unit. The communication device according to claim 1, wherein:
The communication device according to claim 1, wherein the noise detection unit detects ambient noise during a call. The communication device according to claim 3, wherein
A communication device that switches the ear receiver and / or the speakerphone to operate based on surrounding noise information during a call detected by the noise detection unit.

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