JPH09247036A - Small-sized portable radio equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To heat a voice of an opposite party without trouble and to prevent its own voice from being too high by providing an A/D converter converting a transmission voice into a digital voltage, a control section selecting a proper gain control voltage and a D/A converter converting the gain control voltage into an analog voltage. SOLUTION: An analog voltage of a transmission voice received by a transmission microphone 3 is amplified by an amplifier 4 and fed to an A/D converter 5. The A/D converter 5 converts an analog voltage into a digital voltage, which is fed to a control section 7. The control section 7 increases a gain control voltage when a digital voltage of a received transmission voice is high and decreases the gain control voltage when the digital voltage of the received transmission voice is low conversely. Then a D/A converter 6 converts a de-gain control voltage into an analog voltage and its output adjusts automatically a received sound volume being an output of a speaker amplifier 2 and gives the result to a reception speaker 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small portable wireless device which automatically adjusts a reception sound volume.

[0002]

2. Description of the Related Art In a conventional small portable wireless device, when the listening volume is too high or too low, it is manually switched to a preset listening volume level of several stages to adjust to an appropriate listening volume. are doing.

[0003]

However, in such a conventional small portable wireless device, (1) the adjustment cannot be performed when both hands are closed. (2) It is difficult to readjust the received sound volume each time when the ambient sound fluctuates such as becoming loud or soft. (3) When the ambient sound is loud and the listening volume is low, it is difficult to hear and the voice of oneself inevitably becomes loud. However, there was a problem that it was very difficult to use.

The present invention has been made in order to solve the above-mentioned problems, and it is an object of the present invention to provide a small portable radio that can hear the voice of the other party without bothering and prevent the voice from becoming too loud. To aim.

[0005]

To achieve this object, in the present invention, an A / D converter for converting an analog voltage of a transmission sound into a digital voltage and an appropriate gain control voltage from the digital voltage are provided. A control unit for selection and a D / A converter for converting the gain control voltage into an analog voltage are provided.

[0006]

1 is a block diagram showing a small portable radio device according to the present invention.

As shown in the figure, the analog voltage of the transmission sound received by the transmission microphone 3 is amplified by the amplifier 4 and sent to the A / D converter 5. The A / D converter 5 converts the analog voltage of the transmitted sound into a digital voltage and sends the output to the control unit 7. The control unit 7 has a function of outputting a gain control voltage in several stages in response to the input of the digital voltage of the transmission sound, and the digital voltage of the transmission sound input from the A / D converter 5 is high. When the digital control voltage is low, the gain control voltage can be increased. On the contrary, when the digital voltage is low, the gain control voltage can be decreased. Next, D / A
The converter 6 converts the degain control voltage into an analog voltage, the output of the speaker amplifier 2 is adjusted by the converted analog voltage, and the adjusted output is sent to the receiving speaker 1.

Further, as shown in FIG. 2, the gain control voltage once set holds the gain control voltage even during no voice transmission until the next digital voltage of the transmission sound is input. . The control unit 7 has such a memory function. As a result, a good reception sound volume is maintained even when there is no transmission.

Such a small portable radio utilizes the characteristic that the ambient voice is noisy, and when the voice of the other party becomes difficult to hear, the voice of the person who is transmitting becomes unknowingly loud. , When the voice becomes louder, the received sound becomes louder to make it easier to hear. On the other hand, when the voice becomes louder and easier to hear, the voice becomes normal and the received sound returns to normal.

As described above, since the listening volume is automatically adjusted according to the ambient sound and the listening volume, the other party's voice can be heard without bothering and the own voice becomes too loud. Disappears.

[0011]

As described above, in the small portable wireless device according to the present invention, the listening volume is automatically adjusted appropriately according to the ambient sound and the listening volume, so that the voice of the other party can be heard. The annoyance of difficulty is reduced, and a great effect is obtained in improving call quality. In addition, it also has the effect of preventing the voice of the other party from becoming too loud without knowing it because the voice of the other party is difficult to hear.

[Brief description of drawings]

FIG. 1 is a block diagram showing a small portable wireless device according to the present invention.

FIG. 2 is a relationship diagram between a digital voltage of a transmission sound and a gain control voltage.

[Explanation of symbols]

 1 Speaker for reception 2 Speaker amplifier 3 Microphone for transmission 4 Amplifier 5 A / D converter 6 D / A converter 7 Control unit

Claims (1)

[Claims] 1. An A / D converter for converting an analog voltage of a transmission sound into a digital voltage, a controller for selecting an appropriate gain control voltage from the digital voltage, and converting the gain control voltage into an analog voltage. A small portable wireless device having a D / A converter.