JPH08181766A - Loudspeaking equipment - Google Patents

Abstract

PURPOSE: To attain clear bidirectional loudspeaking even when an alarm tone rings by providing a voice switch and an alarm tone ringing means in the equipment. CONSTITUTION: The equipment is provided with a transmission signal level detection section 10 detecting a level of a transmission signal received via a microphone M, a reception signal level detection section 11 detecting a level of a reception signal received via a speech line L, a transmission level variable section 12 varying a level of a transmission signal, and a reception level variable section 13 varying a level of a reception signal, and further a voice switch 14 comparing levels of the signals detected by both the detection sections to decrease a gain of the level variable section for the lower level and to increase a gain of the level variable section for the higher level, and an alarm tone ringing means 15 informing of occurrence of an alarming event. Then alarm tone elimination filters 16, 17 to attenuate an alarm tone are respectively provided at a pre-stage of the transmission signal level detection section 10 and a pre-stage of the reception signal level detection section 11. One to three kinds of sine waves with different frequencies are adopted for the alarm tone.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bidirectional loudspeaker system having a voice switch and an alarm sounding means.

[0002]

2. Description of the Related Art In the conventional intercom system, when a visitor makes a call operation from a child device at the entrance, a resident in the house receives and transmits a call from a parent device installed in a living room or the like. The handset is picked up and the call is made by placing the handset over the ears and mouth. However, in the recent intercom system, in order to pursue convenience, the device itself has a microphone and a speaker so that a call can be made without having to bother to pick up the handset and reach the ear and mouth. A voice communication device that incorporates a so-called hands-free phone is becoming popular.

By the way, in the voice communication device, a microphone and a speaker are incorporated in the device itself. Therefore, if the amplification gain of the communication is increased, the sound from the speaker is picked up by the microphone again. It is easy to cause a call failure. Therefore, by providing a voice switch to increase the amplification gain in the necessary direction while keeping the overall amplification gain for a call constant,
It keeps clear calls while avoiding howling call failures. In addition, in the recent loudspeaker system, it is required to have multiple functions, and an alarm sound is emitted when a predetermined warning event such as a fire or gas leak is confirmed.
The inhabitants in the house and third parties outside are notified of the occurrence of the warning event.

FIG. 5 is a block diagram showing a main part of the conventional voice communication device as described above. As shown in FIG. 5, the loudspeaker system includes a microphone M, a transmission signal level detection unit 10 for detecting the level of a transmission signal input via the microphone M, and a hybrid circuit HYB via a communication line L. A reception signal level detection unit 11 that detects the level of the reception signal that is separated and output at 1, a transmission level change unit 12 that changes the level of the transmission signal, and a reception level change unit 13 that changes the level of the reception signal. , A voice switch 14 that compares the levels of the signals detected by the detection units 10 and 11 to reduce the gain of the lower level variable unit and increases the gain of the higher level variable unit, and a warning event occurs. Then, an alarm sound generation unit 15 corresponding to an alarm sound generation unit that generates an alarm sound and sounds the speaker S to notify the user.

The transmission level varying unit 12 is an amplifying unit 12
a and the variable attenuator 12b, and the reception level varying unit 13 includes an amplifier 13a and a variable attenuator 13b.

The above-mentioned loudspeaker communication device is connected as follows.
ing. That is, the reception signal terminal T ₁Is a hybrid
Reception signal output section of circuit HYB and reception signal level detection section
11 and the input part of the variable attenuator 13b, respectively.
Connect. The output section of the reception signal level detection section 11 is
It is connected to one input section of the voice switch 14. Alarm sound generation
The output of the unit 15 and the output of the variable attenuator 13b are
It is connected to the input section of the section 13a. The output of the amplifier 13a is
Connect to the speaker S. The microphone M is a transmission signal receiver.
Connect the input section of the bell detection section 10 and the input section of the amplification section 12a.
To continue. The output unit of the transmission signal level detection unit 10 is
It connects to the other input of the switch 14. Of the amplifier 12a
The output part is connected to the input part of the variable attenuator 12b,
The output portion of the portion 12b is the transmission signal terminal T₂Connect to. Talk
Signal terminal T₂Is the transmission signal input of the hybrid circuit HYB
Connect to the department. One output part of the voice switch 14 is variable
The other side of the voice switch 14 is connected to the control input section of the attenuating section 12b.
The output part of each is connected to the control input part of the variable attenuator 13b.
To continue.

The voice communication device configured as described above operates as follows. That is, the hybrid circuit HYB
The received signal separated by is the received signal level detection unit 1
1 is transmitted to the speaker S from the reception signal terminal T ₁ through the reception level varying unit 13 and converted into an acoustic signal and transmitted to one of the callers. Further, the voice of the one of the callers is converted into an electric transmission signal by the microphone M, and the converted transmission signal is input to the transmission signal level detection unit 10 and the transmission level is changed. The hybrid circuit H is connected via the unit 12 and the transmission signal terminal T _2.
It is input to the YB transmission input unit.

The voice switch 14 includes both detectors 10 and 11.
When it is determined that the transmission signal is higher than the reception signal, the amplification gain of the transmission level varying unit 12 is increased and the amplification gain of the reception level varying unit 13 is decreased to increase the volume of the voice. The operation mode of the communication device is set to the transmitting state. On the other hand, the voice switch 14 includes both detection units 1.
When the levels of the signals detected by 0 and 11 are compared and it is determined that the reception signal is higher than the transmission signal, the amplification gain of the reception level varying unit 13 is increased and the amplification gain of the transmission level varying unit 12 is decreased. Then, the operation mode of the voice communication device is set to the receiving state.

That is, in any of the above-mentioned operation modes, the voice switch 14 outputs the sum of the amplification gain of the transmitting level varying section 12 and the amplification gain of the receiving level varying section 13 as the sound from the speaker S again to the microphone M. The necessary amplification gain in the speaking direction is increased by controlling the distribution of the amplification gain according to the operation mode, while maintaining a high constant value in the vicinity of which a speech disturbance such as howling caused by being picked up by At the same time, the amplification gain in the unnecessary call direction is reduced, and a clear two-way call without howling is possible while ensuring the necessary volume in the call direction.

[0010]

However, in the loudspeaker communication apparatus using the voice switch 14 as described above, occurrence of a warning event such as fire or gas leak is confirmed, and the alarm sound generator 15 issues an alarm. A sound signal is generated and output, the alarm sound signal is amplified by the amplifier 13a and reaches the speaker S, is converted into an acoustic signal by the speaker S and sounds as an alarm sound, or other alarm equipment (Fig. When an alarm sounding device (not shown) sounds with a loud alarm sound, the alarm sound is picked up by the microphone M as a transmission signal, and the operation mode of the loudspeaker is fixed in the transmission state. However, there is a problem in that the call becomes substantially one-way call and it becomes difficult to perform the two-way voice call when a warning event occurs.

The present invention has been made to solve the above problems, and an object of the present invention is to provide an excellent loudspeaker communication device capable of clear two-way loudspeaking even when an alarm sound is emitted. To provide.

[0012]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides a transmitter for detecting the level of a transmitter signal input via a microphone. A signal level detection unit, a reception signal level detection unit that detects the level of a reception signal input via a telephone line, and a transmission level variable unit that changes the level of the transmission signal,
The gain of the lower level variable unit is decreased and the gain of the higher level variable unit is increased by comparing the levels of the signals detected by both the reception level changing unit that changes the level of the reception signal and the detection unit. In a loudspeaker communication device including a voice switch for turning on and an alarm sounding means for notifying the occurrence of a warning event, an alarm for attenuating the alarm sound at the front stage of the transmission signal level detection unit and the front stage of the reception signal level detection unit. It is characterized in that each of the sound removal filters is provided.

In the invention according to claim 2, the alarm sound is one to three kinds of sine waves having different frequencies.

[0014]

With the above construction, in the invention according to the first aspect, even if the alarm sounds, it is provided in the front stage of the transmission signal level detection unit and in the front stage of the reception signal level detection unit. Since the audible alarm removal filter attenuates the audible alarm,
The voice switch can determine the state mode by comparing the sending signal level with the receiving signal level after excluding the alarm sound, that is, by comparing the level of the sound that is originally necessary.

In the invention according to claim 2, since the alarm sound is composed of one to three kinds of sine waves having different frequencies, only the one to three kinds of frequency components are attenuated. With the narrow band filter, the alarm sound can be removed with almost no influence on the voice and the level comparison of the voice, which is originally necessary, can be accurately performed.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a voice communication device according to the present invention will be described in detail below with reference to FIGS. 1 is a block diagram showing a main part of a voice communication device, FIG. 2 is a characteristic diagram for explaining an alarm sound removal filter, FIG. 3 is a spectrum diagram showing frequency components of an alarm sound, and FIG. 4 is a spectrum showing frequency components of voice. It is a figure. In FIG. 1, the same parts as those of the voice communication device described in the related art are designated by the same reference numerals, and detailed description of the same parts will be omitted.

The loudspeaker communication apparatus shown in FIG. 1 is different from the conventional loudspeaker communication apparatus in that it is characterized by two types of audible frequencies f ₁ generated by the alarm sound generator 15 corresponding to the alarm sounding means. _, f ₂ and an alarm sound removal filter 16 is provided before the transmission signal level detection unit 10, and an alarm sound removal filter 1 is provided before the reception signal level detection unit 11.
7 is provided. In the voice communication device shown in FIG. 1, both the alarm sound removal filter 16 and the alarm sound removal filter 17 have frequency characteristics as shown in FIG. That is, the sharp attenuation characteristic is shown only for two specific frequencies f _{1 and} f ₂ .

Therefore, the above-described voice communication device operates as follows. That is, the reception signal separated by the hybrid circuit HYB is the reception signal terminal T ₁
Is input to the reception signal level detection unit 11 through the alarm sound removal filter 17, and is also transmitted from the reception signal terminal T ₁ to the speaker S through the reception level changing unit 13 and converted into an acoustic signal to be used by one of the callers. Be transmitted to. Further, the voice of the one of the callers is converted into an electric transmission signal by the microphone M, and the converted transmission signal is input to the transmission signal level detection unit 10 via the alarm removal filter 16. At the same time, it is input to the transmission input section of the hybrid circuit HYB via the transmission level changing section 12 and the transmission signal terminal T ₂ .

The voice switch 14 includes both detection units 10 and 11.
In the case where it is determined that the level of the transmission signal is higher than the level of the reception signal, the levels of the signals obtained by removing only the components of the two specific frequencies f _{1 and} f ₂ detected by
The amplification gain of the transmission level varying unit 12 is increased and the amplification gain of the reception level varying unit 13 is reduced, so that the operation mode of the voice communication device is set to the transmission state. On the other hand, the voice switch 14, which is detected by both detectors 10 and 11,
When the levels of the signals obtained by removing only the components of the two specific frequencies f _{1 and} f ₂ are compared and it is determined that the level of the reception signal is higher than the transmission signal, the amplification gain of the reception level varying unit 13 is increased and The amplification gain of the transmission level varying unit 12 is reduced, and the operation mode of the voice communication device is set to the reception state.

In the voice switch 14, the sum of the amplification gain of the transmission level varying section 12 and the amplification gain of the receiving level varying section 13 is the sum of the amplification gain of the transmission level varying section 12 and the sound from the speaker S when the microphone M reappears. The necessary amplification gain in the speaking direction is increased by controlling the distribution of the amplification gain according to the operation mode, while maintaining a high constant value in the vicinity of which a speech disturbance such as howling caused by being picked up by At the same time, it reduces unnecessary amplification gain in the call direction, and enables clear two-way call without howling while securing the required volume in the call direction.

Therefore, in the loudspeaker communication device configured as described above, when the loudspeaker communication device recognizes the occurrence of a predetermined warning event (fire, gas leak, etc.), the alarm sound generation unit 15 outputs Two specific frequencies f as shown in FIG.
An alarm sound signal configured by combining _{1 and} f ₂ is generated and output to the input unit of the amplification unit 13a, and the speaker S is converted into an alarm sound configured by combining two specific frequencies f _{1 and} f _2. And output to space. Then, the alarm sound is picked up by the microphone M and the microphone M → amplifier 12a.
→ variable attenuator 12b → transmission signal terminal T ₂ → transmission input section of hybrid circuit HYB → line connection section of hybrid circuit HYB → call line L → other speaker → other caller Be transmitted to.

However, even if the alarm sound is emitted and picked up by the microphone M, the alarm sound removal filter 1
6 or the alarm sound removal filter 17 attenuates only the alarm sound. That is, the voice switch 14 compares the transmission signal level with the reception signal level after excluding the alarm sound,
That is, it is possible to correctly determine the operation mode for making the receiving state or the transmitting state by comparing the levels of the transmitting voice and the receiving voice, which are originally necessary. Therefore, in this loudspeaker communication device, the problem of the conventional loudspeaker communication device that the operation of the voice switch 14 is fixed to, for example, the transmitting state due to the sounding of the alarm sound, and the two-way communication cannot be smoothly performed. Can be resolved.

In the above embodiment, the structure of the alarm sound
(Spectrum) at a specific frequency f_1,f ₂As the synthetic sound of
There is a specific frequency f_1,f_2,f₃Good as a synthetic sound of
Yes. However, if the specific frequencies that make up the alarm sound increase,
Indeed, the configuration of the alarm sound removal filters 16 and 17 becomes complicated.
In addition, the alarm sound removal filters 16 and 17 are shown in FIG.
Effects on human voice composition (spectrum) as shown
The level of the transmitted voice and the received voice is compared.
Will not be faithful. Therefore, the warning sound is specific at most
It is desirable to synthesize about 3 types of single frequency
Yes.

It is needless to say that the present invention is not limited to the above-described embodiment, and can be applied not only to a loudspeaker communication device such as an intercom system but also to a loudspeaker communication device for a remote conference such as a television.

[0025]

Since the loudspeaker system according to the present invention is constructed as described above, in the invention according to claim 1, the voice switch transmits the alarm sound after the alarm sound is removed by the alarm sound removal filter. While comparing the level of the speech signal and the level of the reception signal, either increase the gain of the transmission level variable part and decrease the gain of the reception level variable part, or increase the gain of the reception level variable part and increase the transmission level. Since it is determined whether or not the gain of the variable unit is reduced, the alarm sound does not fix the transmission state or the reception state, and the two-way communication can be smoothly performed. In the invention according to claim 2, In addition to the above effects, a warning sound removal filter can be easily configured because the warning sound is composed of a small number of single-frequency synthesized sounds, and the voice switch is capable of transmitting and receiving voices as originally intended. Level Comparison can be performed accurately, can be performed more smoothly two-way communication, there is an effect that it provides an excellent hands-free communication device.

[Brief description of drawings]

FIG. 1 is a block diagram showing a main part of an embodiment of a voice communication device according to the present invention.

FIG. 2 is a characteristic diagram illustrating an alarm sound removal filter of the above embodiment.

FIG. 3 is a spectrum diagram showing frequency components of an alarm sound of the above-mentioned embodiment.

FIG. 4 is a spectrum diagram showing frequency components of voice.

FIG. 5 is a block diagram showing a main part of a conventional voice communication device.

[Explanation of symbols]

 10 transmission signal level detection unit 11 reception signal level detection unit 12 transmission level variable unit 13 reception level variable unit 14 voice switch 15 alarm sounding means 16 alarm sound removal filter 17 alarm sound removal filter L communication line M microphone

Claims (2)

[Claims] 1. A transmission signal level detecting unit for detecting a level of a transmission signal input via a microphone, and a reception signal level detecting unit for detecting a level of a reception signal input via a telephone line. The transmission level varying unit for varying the level of the transmission signal, the reception level varying unit for varying the level of the reception signal, and the level variation unit of the lower one comparing the levels of the signals detected by the detection units. In a loudspeaker communication device including a voice switch for decreasing the gain and increasing the gain of the higher level variable section, and an alarm sounding means for informing of the occurrence of a warning event, in a voice communication device, the front stage of the transmission signal level detection section and the reception signal. A loudspeaker communication device, characterized in that an alarm sound removal filter for attenuating an alarm sound is provided in front of the level detection unit. 2. The loudspeaker communication apparatus according to claim 1, wherein the alarm sound is one to three kinds of sine waves having different frequencies.