JPH11205436A - Hand-free telephone set - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the hand-free telephone set of a voice switching system capable of easily judging the transmission/reception state without switching the transmission/reception state in the middle of a speech at the time of performing speech by the hand-free telephone set. SOLUTION: Whether or not the transmission voice of a speaker by hand-free inputted from a microphone 10 is higher than a prescribed voice level is detected in a peak detection circuit 12, and in the meantime, whether or not reception voice inputted through a telephone line is higher than the prescribed voice level is detected in the peak detection circuit 20. Based on both detection values, a half duplex control part 22 maintains the one of the transmission state and the reception state so as to continuously transmit the voice for which it is detected that it is higher than the prescribed voice level first. A green LED 24 is lighted in the transmission state and a red LED 26 is lighted in the reception state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hands-free telephone, and more particularly to a hands-free telephone of a voice switching system.

[0002]

2. Description of the Related Art Conventionally, a voice switching type hands-free telephone has been known. This is configured to detect a voice to be transmitted / received and alternately turn on / off a microphone and a speaker so that transmission / reception can be performed without having to pick up a receiver.

Further, Japanese Patent Application Laid-Open No. 64-1358 discloses that
In the above voice switching type hands-free telephone, a green LED is turned on during the transmitting state so that the user can determine whether the apparatus is in the transmitting state or the receiving state. In this case, a device that turns on a red LED at the time is disclosed. In this hands-free telephone, the transmission state and the reception state are switched by comparing which of the reception voice level and the transmission voice level is higher. That is, when the transmitted voice level is higher than the received voice level, the transmitting state is set and the green LED is displayed. On the other hand, when the received voice level is higher than the transmitted voice level, the receiving state is set. A red LED is displayed.

[0004]

However, in the hands-free telephone disclosed in the above publication, the transmission and reception are switched based on the level of the voice level, so that the transmitter is in the middle of talking (transmission state). However, if the other party starts speaking and the voice level of the other party is higher, the receiving state is set. For this reason, the contents intended by the sender using the hands-free telephone may not be transmitted and may not be transmitted to the other party.

[0005] Particularly, when the other party does not use a hands-free telephone, the other party can transmit and receive at the same time, so that the talker may start a conversation even while the talker is talking. As described above, there is a problem that even when the sender is talking, the receiver suddenly enters the receiving state, and there is a high possibility that the speech will not be transmitted at a time not intended by the sender.

Therefore, the present invention provides a voice switching system which enables a call to be made by a hands-free telephone without the transmission / reception state being switched during the conversation and for easily determining the transmission / reception state. The purpose is to provide a hands-free telephone.

[0007]

According to the first aspect of the present invention, in a voice-switching hands-free telephone, the first voice level comparing unit and the second voice level comparing unit transmit and receive voice. Are respectively compared with predetermined levels, and any of the voices previously determined to be higher than the predetermined level by the voice selection unit and the voice connection unit are selected and connected to the communication path, and the predetermined level is maintained. During this time, the connection to this communication path is maintained. Then, the connection state to the communication path is displayed on the display unit.

Accordingly, during the transmission of the user's speech, the transmission voice is received and maintained at a predetermined level or more, so that the transmission status in which the transmission voice is connected to the communication path is maintained. , Can continue the transmission. On the other hand, when the other party is talking (during reception), the received voice is maintained at a predetermined level or higher, so that the received voice is in a receiving state in which the received voice is connected to the communication path, and the receiving voice is maintained. it can. Therefore, the transmission / reception state is switched during transmission / reception and the conversation is not interrupted.

Also, since the connection state is displayed, the user can know whether the state is the transmission state or the reception state, and the transmission and reception can be performed more reliably. is there.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a hands-free telephone according to the present invention will be described below with reference to FIGS. FIG. 1 is a block circuit diagram showing one embodiment of the present invention, and FIG. 2 is an explanatory diagram showing a call state.

In the hands-free telephone of this embodiment, a transmission voice input from a microphone 10 is input to a peak detection circuit 12 via a transmission amplifier (not shown), and a peak detection value of the peak detection circuit 12 is obtained. Is the half-duplex control unit 22
Is input to The received voice input via the telephone line is input to a peak detection circuit 20 via a reception amplifier (not shown), and the detected peak value is transmitted to the half-duplex control unit 2.
2 is input.

The peak detecting circuit 20 constitutes a second audio level comparing section of the present invention, and compares the level of the received voice input from the telephone line with a predetermined voice level, and determines whether the level of the received voice is high. If the sound level is equal to or higher than a predetermined sound level, a peak detection value is output. The predetermined audio level is, for example, -32 dBm0 in PHS line conversion. The detection by the peak detection circuit 20 is always performed during non-detection, and is performed approximately every 100 ms during detection.

On the other hand, the peak detecting circuit 12 constitutes a first audio level comparing section of the present invention, and the microphone 1
The level of the transmitted voice input from 0 is compared with a predetermined voice level, and if the level of the transmitted voice is equal to or higher than the predetermined voice level, a peak detection value is output. The predetermined audio level in the peak detection circuit 12 is, for example, -22 dBm0 in PHS line conversion. The detection by the peak detection circuit 12 is performed in synchronization with the detection by the peak detection circuit 20.

The half-duplex control unit 22 constitutes the voice selection unit of the present invention, monitors the peak detection values input from each of the peak detection circuits 12 and 20, and controls the half-duplex control unit 22 as shown in FIG.
The transmission / reception state shown in (b), (c), and (d) is determined, and one of the transmission state and the reception state is determined. The attenuator 14 adjusts the transmission voice input from the microphone 10 via the peak detection circuit 12 and transmits the adjusted voice to the telephone line in the transmission state according to the transmission / reception state determined by the half-duplex control unit 22. Things.

The attenuator 18 adjusts the received voice input from the telephone line via the peak detection circuit 20 to the speaker 16 in the receiving state according to the transmitting / receiving state determined by the half-duplex control unit 22. To communicate, the speaker 16
Transmits the received voice. LED24
Is lit in green while the half-duplex control unit 22 is in the transmission state.

The LED 26 is illuminated in red while the half-duplex control unit 22 is in a receiving state. Next, the operation of the hands-free telephone configured as described above will be described with reference to FIG. As shown in FIG. 2A, when both the transmitter and the other party are silent, the peak detection values are not output from the peak detection circuits 12 and 20 in comparison with the predetermined voice level.
In this embodiment, in such a case, the half-duplex control unit 22
, The transmitting state is set and the green LED 24 is turned on so that the voice of the transmitter can be transmitted.

As shown in FIG. 2 (b), when the state of FIG. 2 (a) changes and the sender speaks and the other side is silent, the peak detection circuit 12 on the side of the talker outputs a peak. The detection value is output, and the peak detection circuit 20 on the receiving side does not output the peak detection value. In this case, the transmission state is set and the green LED 24 is turned on so that the voice of the transmitter side is transmitted.

On the other hand, as shown in FIG.
When the receiving side utters and the sender is silent, the state changes from the state of (a), and a peak detection value is output from the peak detecting circuit 20 on the receiving side, and the peak detecting circuit 12 on the transmitting side outputs a peak. No detected value is output. In this case,
The receiver is set to the receiving state so that the voice of the receiving side is transmitted, and the red LED 26 is turned on.

As shown in FIG. 2D, when both the transmitter and the receiver are speaking, both peak detection circuits 1 are used.
At 2 and 20, peak detection values are output. In this case, it is set so that the voice of the person who uttered first is transmitted to the other party. That is, even if the receiving side utters in the transmitting state shown in FIG. 2B, if the peak detection value in the peak detecting circuit 12 on the transmitting side is continuously output, the transmitting state is not changed. To maintain. In this case, the green LED 24 is turned on to indicate the transmission state.

On the other hand, even if the transmitter utters in the receiving state shown in FIG. 2C, if the peak detection value in the peak detecting circuit 20 on the receiving side is continuously output, Maintain the listening state. In this case, the red LED 26 is turned on to indicate the receiving state. By operating as described above, if either the transmitter or the receiver is uttering, even if the other erroneously utters, the sound of the originally uttering side will not be interrupted, and the hands will not be interrupted. During a free call, conversation can be performed more smoothly.

Further, since the transmitting state or the receiving state at that time is displayed using the LEDs 24 and 26, the user can visually confirm the current state.
In the receiving state, there is an effect that a situation in which the utterance content is not transmitted to the other party even though the user utters the voice is eliminated. In the above embodiment, the case where the predetermined audio level in the peak detection circuit 20 is a fixed level has been described. However, a plurality of levels may be provided according to the amount of sound. For example, it has three levels according to the loudness of large, medium, and small voices. The predetermined audio level may be switched between the predetermined audio level and the predetermined audio level when the audio level is set to low.

Further, in the above embodiment, the display unit is LE
Although the example using D24 and D26 has been described, it may be displayed on an LCD screen or the like.

[Brief description of the drawings]

FIG. 1 is a block circuit diagram of a speakerphone telephone according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a call state;

[Explanation of symbols]

 12 Peak detection circuit (first audio level comparison unit) 14, 18 Attenuator (audio connection unit) 20 Peak detection circuit (second audio level comparison unit) 22 Half duplex control unit (audio selection unit) 24, 26 LED (display unit)

Claims (1)

[Claims] 1. A voice-switching hands-free telephone, comprising: a first voice level comparing section for comparing a level of a transmitted voice with a first predetermined level; and comparing a level of a received voice with a second predetermined level. A second audio level comparing section; an audio selecting section for selecting any audio previously determined to be equal to or higher than a predetermined level by the first audio level comparing section and the second audio level comparing section; Connecting either the transmission voice or the reception voice to the communication path based on the selection of the voice selection unit, and transmitting or receiving the transmission voice or the reception voice while the selected voice maintains the predetermined level or more. A hands-free telephone comprising: a voice connection unit that maintains a connection of voice to a communication path; and a display unit that displays a connection state of the voice connection unit.