JPH0583353A - Telephone set with reception sound volume automatic adjustment function - Google Patents

Abstract

PURPOSE:To attain always stable reception by detecting a surrounding noise level and controlling a gain of a variable gain amplifier provided to a reception talking system so as to adjust the reception sound volume. CONSTITUTION:The telephone set is provided with a surrounding noise detection circuit 9 having a microphone and a microphone amplifier or the like connecting to a control circuit 6, which detects a noise level around the telephone set under the control of the control circuit 6 and the level is fed to the control circuit 6. Moreover, a speech circuit 2 is provided with a reception amplifier 10 whose amplification factor is variable to amplify a voice signal from a voice signal line 1 and the amplification factor of the reception amplifier 10 is controlled optimizingly automatically based on the output of the circuit 9 in talking state so that the amplification factor is higher when the noise level is high by the control circuit 6 and the amplification factor is reduced when the noise level is low, and the amplified voice signal is fed to a speaker 3 selected by a reception changeover circuit 7 or a receiver of a handset 4. Moreover, the power supply to each circuit block is supplied from a power supply circuit 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a telephone having a function of automatically and optimally adjusting the volume of received voice according to the ambient noise level.

[0002]

2. Description of the Related Art Telephones are installed everywhere in a house or in a town. Therefore, if there is a lot of noise around the telephone, it becomes difficult to hear the received voice. As a solution to such a problem, a telephone having a volume knob for adjusting the reception volume and a telephone having a selector switch for switching the reception volume have been proposed. In addition, Japanese Utility Model Laid-Open No. 3-776 proposes a telephone in which the receiving volume can be switched by operating a dial key or the like in a handset call state.

[0003]

However, in each of the above-mentioned conventional telephones, since the volume of the received voice is adjusted or switched by a manual operation, there is a problem that the operation is troublesome and the operation is difficult. There may be a problem that a mistake makes it impossible to hear the listening.

The present invention has been made by paying attention to such a conventional problem, and automatically optimizes the listening volume according to the ambient noise without performing troublesome manual adjustment and switching operation. It is an object of the present invention to provide a telephone with a reception volume automatic adjustment function that is capable of being adjusted and therefore is appropriately configured to always receive a stable reception.

[0005]

In order to achieve the above object, according to the present invention, there is provided a variable gain amplifier connected to an incoming call communication system for amplifying a voice signal from a voice signal line, and a surrounding for detecting a noise level of the surroundings. A noise detection circuit and a control circuit for controlling the gain of the variable gain amplifier based on the output of the ambient noise detection circuit are provided.

[0006]

In such a structure, when the ambient noise level is detected by the ambient noise detection circuit, the gain of the variable gain amplifier is controlled by the control circuit based on the detected output, whereby the reception volume is automatically optimized. Adjusted.

[0007]

1 is a block diagram showing the essential parts of an embodiment of the present invention. This embodiment is applied to a telephone capable of receiving a speaker. The voice signal line 1 is connected to the call circuit 2, and the speaker 3 and the handset 4 are connected to the call circuit 2.
And the sound source circuit 5 is connected. Further, the speech circuit 2 and the tone generator circuit 5 are connected to a control circuit 6, and the control circuit 6 responds to an incoming call and the speech circuit 2 by the tone generator circuit 5 is connected.
In addition to controlling the transmission via the telephone, the reception switching circuit 7 of the communication circuit 2 is controlled by a key input such as a speaker button (not shown) so that the reception by the speaker 3 and the reception by the handset 4 are selected. .. Further, a reset circuit 8 is connected to the control circuit 6 so that an initial reset for the control circuit 6 is performed and the runaway of the control circuit 6 is stopped based on the watchdog timer input for runaway monitoring. To do.

In this embodiment, an ambient noise detecting circuit 9 having a microphone and a microphone amplifier connected to the control circuit 6 is provided.
The noise level around the telephone is detected and supplied to the control circuit 6 under the control of the control circuit 6. In addition, the call circuit 2 is provided with a reception amplifier 10 having a variable amplification factor for amplifying a voice signal from the voice signal line 1, and the amplification factor of the reception amplifier 10 is based on the output of the ambient noise detection circuit 9 in the communication state. The control circuit 6 automatically and optimally controls the amplification factor to be high when the noise level is high and to be low when the noise level is low, and the amplified voice signal is controlled by the reception switching circuit 7. The handset of the selected speaker 3 or handset 4 is supplied. The power supply to each of the above circuit blocks is supplied from the power supply circuit 11.

In the above structure, the microphone constituting the ambient noise detecting circuit 9 is located at a position where the influence of the voice of the caller is small.
For example, it is attached to an appropriate position inside the telephone body or on the side surface of the telephone body. Further, the amplification factor of the reception amplifier 10 may be continuously changed according to the output of the ambient noise detection circuit 9 with a predetermined amplification factor as a lower limit value.
You may make it change stepwise.

According to this structure, according to the ambient noise level, when the noise level is high, the listening volume is increased, and when the noise level is low, the listening volume is automatically and optimally controlled, which is troublesome. You can always receive a stable voice without performing manual adjustments and switching operations.

The present invention is not limited to the above-described automatic adjustment of the listening volume in the call state, and the receiving volume is automatically adjusted based on the output of the ambient noise detection circuit even when the extension is individually or simultaneously called. Can be adjusted. Also,
It is needless to say that the present invention can be effectively applied not only to the above-mentioned telephone capable of receiving a speaker, but also to a telephone having no speaker receiving function.

[0012]

As described above, according to the present invention, the ambient noise level is detected, and based on the output, the gain of the variable gain amplifier provided in the receiving communication system is controlled to automatically adjust the receiving volume. Since the optimum adjustment is made, even if the ambient noise level changes in various ways, it is possible to always receive a stable voice without any troublesome manual adjustment or switching operation.

[Brief description of drawings]

FIG. 1 is a block diagram showing a main part of an embodiment of the present invention.

[Explanation of symbols]

 1 voice signal line 2 speech circuit 3 speaker 4 handset 5 sound source circuit 6 control circuit 7 reception switching circuit 8 reset circuit 9 ambient noise detection circuit 10 reception amplifier 11 power supply circuit

Claims (1)

[Claims] 1. A variable gain amplifier connected to an incoming call communication system for amplifying a voice signal from a voice signal line, an ambient noise detecting circuit for detecting an ambient noise level, and an output of the ambient noise detecting circuit. And a control circuit for controlling the gain of the variable gain amplifier.