JP2502539B2 - Loudspeaker - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to the above-mentioned communication between a sound collection / loudspeaker unit installed at a plurality of acoustically separated locations or a communication partner via a communication line. The present invention relates to a loudspeaker communication device for performing a loudspeaking conference call with a sound pickup / loudspeaker unit.

More specifically, the present invention relates to a loudspeaker communication device in which a plurality of sound collection / loudspeaking units including a speaker and a microphone can be connected and howling echo generated by acoustic coupling is prevented.

[Prior Art] Conventionally, when participating in a conference call using a loudspeaker, it is necessary to go to the place even when the conference is held in another room in the same building. In addition, it was possible to participate in the conference by telephone only when the conference was held using a public telephone line and the use of the conference call bridge (installed in the telephone office) was registered.

Therefore, it was not possible to use the microphone and speaker to participate in the conference call while staying in my room.

[Problems to be Solved by the Invention] On the other hand, as a countermeasure against the above, as shown in FIG. 5, a pair of microphone speakers 1 _-1 to 1 _-3 among a plurality of microphone speakers connected to a current loudspeaker. A method of dispersively arranging in units can be considered. However, in this case, there is a drawback that communication between different rooms cannot be realized.

As a method to make this possible, it is possible to install a distribution / addition circuit between each speaker / microphone unit and the loudspeaker, but in that case, howling and echo between the rooms may occur. Is newly derived, and it becomes necessary to prevent this.

Therefore, as shown in FIG. 6, when the voice switches 6 _{-1 to} 6 _-3 are inserted, the voice switch 4 of the communication device itself already exists. And four voice switches are inserted in series between the receiver and the receiver. As a result, there arises a problem that the call quality is greatly impaired.

Further, if a call interruption is made from a certain microphone / speaker unit side while the other party of the call via the communication line 5 is transmitting, the voice switch 4 acts on all listeners side which are other microphone / speaker units. The transmission of the call partner will be disconnected.

[Object of the Invention] In view of the above points, an object of the present invention is to provide a convenient and high-quality function that allows a user to easily participate in a conference held in another place while staying in different rooms. It is to provide a voice communication device that can be realized.

[Means for Solving the Problems] In order to achieve the above-mentioned object, a loudspeaker communication device according to the present invention is provided between sound pickup / loudspeaker units installed at a plurality of acoustically separated places, or In a loudspeaker communication device that performs a loud conference call between a communication partner via the communication line and the sound collection / loudspeaker unit, the sound pickup circuit and the loudspeaker circuit included in the sound pickup / loudspeaker unit are mutually connected to each other. A first variable loss circuit (corresponding to 7, 8 and 9 in FIG. 1) respectively connected to the sound pickup circuit and the loudspeaker circuit for coupling, and a sound pickup included in the sound pickup / loudspeaker unit. A second variable loss circuit (corresponding to 10, 11, 12 in FIG. 1) which is inserted between the circuit and the loudspeaker circuit and the other party of the call and gives a variable loss corresponding to each of the sound pickup circuit and the loudspeaker circuit. Output from each of the sound collecting circuits. Based on the talk signal level, or on the basis of the reception signal level coming from said transmission talk signal level and said communication line,
And a voice switch control circuit (corresponding to 20 in FIG. 1) for controlling the insertion resistance values of the first and second variable loss circuits.

Such an embodiment of the present invention has the following features.

One voice switch (or two if the other party is included) is inserted during a voice call via a pair of communication lines, and only one voice switch is also inserted during a voice call between each loudspeaker. It is characterized by
This is different from the case where an attempt is made to realize the related art by unnecessarily inserting voice switches in multiple steps during a voice call with a communication partner.

Even if there is a call interruption from any of the loudspeakers on the side of the self-expanding speech communication device during a conference call via the communication line, the sound-enhancing device other than the sound-enhancing device can switch the conversation voice of the other party to the voice switch of the self-expanding communication device. It is possible to listen together with the transmission interruption signal without being disconnected by. On the other hand, in the related art, the conversation voice of the other party is cut off by the transmission interruption.

The volume control of all received signals (speech signals of other loudspeakers and transmission signals of the communication partner) input to the loudspeaker is specified by a plurality of volume control knobs provided on the loudspeaker, and the volume The adjustment control signal is collected and executed by the voice communication device.

Similar to the volume control, the mute function for transmission is controlled by a plurality of mute buttons provided in the loudspeaker, and the control signal is collected and executed by the loudspeaker.

When using the telephone conference bridge, it is necessary to use a plurality of telephone lines and register with the telephone conference bridge. However, according to the public address communication device, one communication line and a dedicated extension are enough. That is, it suffices to prepare a dedicated extension connection terminal in each room scheduled to participate in the conference.

EXAMPLES Hereinafter, the present invention will be described in detail based on examples.

FIG. 1 is a block diagram showing an embodiment of the present invention.
In the figure, 1 _-1 , 1 _-2 , 1 _-3 are loudspeaker devices composed of microphones and speakers, 2 _-1 , 2 _-2 , 2 _-3 are the loudspeaker devices described above and the voice calls according to this embodiment. An extension for connecting the device 3, 5 is a communication line, 3 _-1 is a microphone mixer, 3 _-2 is a voice amplifier, and 3 _-3 is a communication line interface circuit (4-wire / 2-wire conversion circuit).

7,8,9,10,11,12 is variable loss circuit, _7-1 contained therein, 7 _{-2, 28-1, 8-2, 9-1,} 9 _-2, 10 _{- 1} , 10 _-2 , 11
_-1 , 11 _-2 , 12 _-1 , and 12 _-2 indicate the variable losses inserted in the transmission and reception paths, respectively.

Reference numeral 20 is a voice switch control circuit, and its input signals a, b,
c and d are transmission signals of the loudspeakers 1 _-1 , 1 _-2 , 1 _-3 and the communication line 5
The received signal from is shown. The output signals A, B, C, D, E, F of the voice switch 20 are signals for controlling the amount of insertion loss of the variable loss circuits 7, 8, 9, 10, 11, 12.

FIG. 2 is a flowchart showing the control procedure of the voice switch control circuit 20 shown in FIG. The operation of this embodiment will be described below according to the control procedure shown in the figure.

Each loudspeaker unit 1 _-1, 1 _-2, transmission signal sent from the microphone included in 1 _-3 is detected by the voice switch control circuit 20 of the hands-free communication device 3. At the same time, the voice reception control circuit 20 also detects the reception signal that has arrived at the voice communication device 3 via the communication line 5 (step S2). The voice switch control circuit 20 in the loudspeaker 3 performs level comparison between the loudspeakers and between the loudspeakers and the communication line side reception input using the detected signals (step S
4), the variable loss circuit 7,8,9,10,1 based on the judgment result
Insert and remove losses of 1 and 12 (step S6). As a result, howling and echo are prevented and a comfortable voice call is realized.

The above operation will be described in more detail below. The transmission signal transmitted from the microphone included in the loudspeaker 1 _-1 is input to the loudspeaker 3 via the extension 2 _-1 , and the signal level thereof is detected by the voice switch control circuit 20. At the same time, the voice switch control circuit 20 also detects the level of the reception signal input to the voice communication device 3 through the communication line 5. Moreover, the level of the transmission signal sent from the microphone of the other loudspeaker device 1 _-2, extension 2
It is detected by the voice switch control circuit 20 via _-2 .

As shown in the flow chart of FIG. 2, the voice switch control circuit 20 of the loudspeaker 3 is provided with the loudspeakers 1 _-1 and 1 _-2.
The level of the transmission signal from is compared, and if it is (1 _-1 side> 1 _-2 side), the variable loss circuit 7
One of the losses (7 _-2 ) is removed and the other loss (7 _-1 )
Insert.

Further, the voice switch control circuit 20 compares the level of the transmission signal level from the loudspeaker 1 _-1 side with the signal level from the communication line 5 side, and similarly communicates with the loudspeaker 1 _-2 side transmission signal level. The magnitude of the signal level from the line 5 side is compared. Therefore, if the voice switch control circuit 20 determines that (1 _-1 side> 5 side), one loss (10 _-1 ) of the variable loss circuit 10 is removed based on the determination result and the other loss ( Insert 10 _-2 ). If (1 _-2 side <5 side), one loss (11 _-2 ) of the variable loss circuit 11 is removed based on the determination result, and the other loss (11 _-1 ) is inserted.

Furthermore, since the microphone loudspeaker device 1 _-3 no transmission signal is transmitted, the audio switch control circuit 20 of the hands-free communication device 3 determines that (1 _-3 side <5 side), the variable loss circuits 1
Remove one loss (12 _-2 ) of ₂ and insert the other (12 _-1 ) loss. Similarly, the loudness levels of the loudspeakers 1 _-3 and 1 _-2 and the loudspeakers 1 _-3 and 1 _-1 are judged, and the loss (9 _-2 ) which is one of the variable loss circuits 9 is removed, On the other hand (9 _-1 )
Of the variable loss circuit 8, one loss (8 _-2 ) of the variable loss circuit 8 is removed, and the other loss (8 _-1 ) is inserted.

Since it operates in this way, for example, the transmission signal on the side of the loudspeaker 1 _-1 is transmitted to the other party via the communication line 5 and the other loudspeaker (1 _-2 , 1 _-3 ) side of the self-loudspeaker side. Sent to
The received signal from the communication partner is heard on the side of the loudspeaker (1 _-2 , 1 _-3 ), and the voice transmitted by the loudspeaker 1 _-2 is the loudspeaker 1
_-Listen only at _-3 . That is, the loudspeaker 1 _-1 is a transmitter, the loudspeaker 1 _-2 is a receiver for the communication partner and the loudspeaker 1 _-1 , and the loudspeaker 1 _-3 is a communication partner, the loudspeaker 1
It becomes receiver relative to _-1 and 1 _-2. In addition, the communication partner receives the call to the loudspeaker 1 _-1 , and the loudspeakers 1 _-2 and 1
_-3 will be transmitted.

This is an example of simultaneous calls, but in the case of alternating conversations, it is of course possible to listen to each other's voice without disconnecting the conversation. Further, although FIG. 1 shows a configuration in which three loudspeakers are connected, it is of course easy to increase the number of loudspeakers, and the applications are further expanded.

With such a configuration, a loudspeaker including a microphone / speaker can be installed in various places. Also in this case, the voice switch control circuit in the loudspeaker system can be configured to collectively receive the transmission signal and the reception input signal from the communication partner.

Further, in this embodiment, the size of the transmission / reception level is judged sequentially for all speech paths, and the amount of voice switch loss inserted in each speech path is controlled. (7,8,9) is done only once, and is only inserted up to twice with the communication partner including the voice switch (corresponding to 10, 11, 12) on the partner side.

As a result, it is possible to easily participate in the conference by using the loudspeaker installed at each desired place, and further, it is possible to minimize the number of voice switches to be inserted in the communication path, thereby reducing disconnection of voice. can do. When this function is realized by the conventional technique, the voice disconnection becomes remarkable due to the insertion loss of the voice switches inserted in multiple stages, which causes the deterioration of the call quality. In addition, it is possible to prevent the voice received from the communication partner from being heard by the other loudspeaker because the voice is transmitted by the certain loudspeaker.
Moreover, since the voice switch control circuit 20 needs only the signal input to the loudspeaker 3 as an input signal, the voice switch control circuit 20 has a circuit scale larger than that of the system in which the voice switch circuits are distributed to the loudspeakers (see FIG. 6). Has the advantage of being small.

FIG. 3 is a block diagram for explaining another embodiment of the present invention. 1 _-1 shown in the figure is the same loudspeaker as described in FIG. Reference numeral 3'denotes a voice communication device according to this embodiment. Reference numeral 20 'is a voice switch control device, which includes A, B, C, D, E,
F is a control signal for controlling the loss amount of the variable loss circuits 7 to 12 (not shown) for performing mute / sending volume control. 5 is a communication line, e, f, g are loudspeakers ₁ other than the loudspeaker 1 _-1
-2, mute button to a communication counterpart via a 1 _-3 and the communication line 5. h, i, j are loudspeakers ₁ other than loudspeaker 1 _-1
-2 shows a volume control knob for the signal inputted from the communication partner via the 1 _-3 and the communication line 5. Note that the mute button and the earpiece volume control knob in other loudspeakers are the same, and are therefore omitted.

FIG. 4 is a flow chart showing a control procedure of the voice switch control circuit relating to the mute / volume control of the transmission.

Next, the operation of FIG. 3 will be described according to the flowchart of FIG. First, set up the "loudspeaker volume knobs h, i, j" corresponding to the other loudspeakers 1 _-2 , 1 _-3 and the communication partner equipped in each loudspeaker 1 _-1 , 1 _-2 , 1 _-3. It adjusts and raises / lowers the reception level of the signal. Similarly, "another sound amplification system 1 _-2, 1 _-3 and communication partner mute button e corresponding, f, g"
By operating, the transmission of the transmission signal to the communication path is stopped. Here, all the control signals of the reception volume and the transmission mute are transmitted through the lines 2 _-1 , 2 _-2 , 2 _-3 connecting the loudspeakers 1 _-1 , 1 _-2 , 1 _-3 and the loudspeaker 3 Is input to the voice switch control circuit 20.

Third other public address system shown in FIG. 1 _-2, 1 together with that control signal sent from _-3, the input signals for the receiver volume and sending mute collectively to the audio switch control circuit 20 ' To be done. Then, regarding the reception volume adjustment, it is converted into a required signal for adjusting the insertion loss, and regarding the transmission mute, it is converted into a required signal for performing the loss control as on-off information, and each insertion loss circuit 7, 8, Insertion loss amount of 9,10,11,12 is controlled by control signals A, B, C, D, E, F.

As a result, the level of the audio signal input to the loudspeaker can be adjusted individually and the mute of the transmission can also be adjusted individually, so that a temporary confidential call can be made only with the other party desired by the user.

[Effects of the Invention] As described above, by carrying out the present invention,
The need to go to the place where the conference call is being made is greatly reduced, and the user can join the conference from his / her room / seat according to the contents of the conference. Further, the conference organizer side can call a busy person at a necessary time during the conference and have him or her join the conference without keeping the busy person in the conference.

In addition, the variable loss circuit for voice switch has a configuration in which only one set is inserted regardless of which speech path is taken, and since it is not inserted in multiple stages, excellent speech quality can be realized. Further, according to the present invention, it is possible to conduct a conference (a conference only for extension lines) under the condition that the communication line is not connected.

[Brief description of drawings]

1 is a block diagram showing a voice communication device according to an embodiment of the present invention, FIG. 2 is a flow chart showing a control procedure of a voice switch control circuit shown in FIG. 1, and FIG. 3 is another embodiment of the present invention. FIG. 4 is a flowchart showing the control procedure of the voice switch control circuit shown in FIG. 3, and FIG. 5 is a loudspeaker composed of a set of voice switch variable loss circuits and a voice switch control circuit. FIG. 6 is a loudspeaker conference device diagram having a plurality of sets of voice switch circuits that enable a call between a plurality of loudspeaker devices. 1 _-1 , 1 _-2 , 1 _-3 ...... Loudspeaker with microphone / speaker, 2 _-1 , 2 _-2 , 2 _-3 ...... Extension 3 ...... Loudspeaker, 3 _-1 ...... Microphone Mixer, 3 _-2 ... Received signal amplifier, 3 _-3 ... Communication line interface circuit, 4 ... Voice switch circuit equipped with insertion loss / voice switch control circuit, 5 ... Communication line, 1 _-1 ', 1 _-2 ', 1 _-3 ' …… Speaker system consisting of microphone, speaker, voice switch and amplifier circuit, 6 _-1 , 6 _-2 , 6 _-3 …… Sound switch circuit included in the system, 7,8, 9,10,11,12 …… Voice switch variable loss circuit, 7 _-1 , 7 _-2 , 8 _-1 , 8 _-2 , 9 _-1 , 9 _-2 , 10 _-1 , 1
0 _-2 , 11 _-1 , _{-11 -2} , 12 _-1 , 12 _-2 ...... Variable loss inserted into each channel, 20 ...... Voice switch control circuit, a, b, c, d…
… Speaking signal of the loudspeaker and receiving signal from the communication line side,
A, B, C, D, E, F …… Variable loss circuit control signal from the voice switch control circuit, e, f, g …… Sending mute button, h, i, j …… Speaker volume control knob.

Claims (3)

(57) [Claims] 1. A loud conference call between sound collecting / speaking units installed in a plurality of acoustically separated locations, or between a communication partner and the sound collecting / speaking unit via a communication line. In a loudspeaker communication device for performing the above-mentioned sound pickup circuit, a first variable loss circuit connected to the sound pickup circuit and the loudspeaker circuit, respectively, in order to mutually couple the sound pickup circuit and the loudspeaker circuit included in the sound pickup and loudspeaker unit. And a sound collecting circuit included in the sound collecting / speaking unit and the sound collecting circuit and the other party of the call, and giving a variable loss corresponding to each of the sound collecting circuit and the sound collecting circuit.
Variable loss circuit, and based on the transmission signal level sent from each of the sound collecting circuits, or based on the transmission signal level and the reception signal level incoming from the communication line, the first and A voice communication device comprising a voice switch control circuit for controlling an insertion resistance value of a second variable loss circuit. 2. A plurality of manually adjusted reception volume control signals are input to the voice switch control circuit to control insertion loss of the first and second variable loss circuits.
The loudspeaker communication device according to claim 1, characterized in that a sound volume received from the sound collection / loudspeaker unit and the communication partner is adjusted. 3. A plurality of manually controlled mute signals are input to the voice switch control circuit, and the first and second mute signals are input.
2. The voice call according to claim 1, wherein muting is performed between the sound collecting / loudspeaking units and between the communication partners by controlling the insertion loss of the variable loss circuit of FIG. apparatus.