JPH0120572B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a voice press talk device that uses voice recognition to switch between transmission and reception in a wireless device or the like.

Prior Art and Problems In a communication device consisting of a half-duplex transceiver such as an amateur radio or a personal radio, communication is performed in a one-way communication format, so while switching between transmission mode and reception mode, It is necessary to communicate. Conventionally, such switching between transmission and reception modes has often been performed manually using a press talk switch provided on a microphone, handset, or the like.

However, in the case of an on-vehicle radio, especially when it is desired to communicate while the vehicle is running, manual operation of the press talk switch is dangerous and cannot be performed. Therefore, it is desirable to be able to perform the press talk operation without having to do it manually.

Conventionally, for such purposes, a voice control method has been widely used in which transmission and reception are switched depending on the presence or absence of voice. However, since the voice control method switches between transmission and reception by simply determining the presence or absence of transmitted voice, there is a problem in that the mode switches to reception mode as soon as there is a pause in speech even during a conversation. Therefore, it is necessary to transmit calls continuously without interrupting the audio.
This is quite mentally stressful, and especially in the case of vehicle-mounted radios, it poses a problem in terms of driving safety. Furthermore, switching between transmission and reception due to voice detection involves a slight time delay, which tends to cause so-called interruptions at the beginning of speech. In particular, in the case of personal radios, a group code of about 0.2 seconds is sent at the beginning and end of transmission, which causes a large degree of disconnection at the beginning of the conversation, which poses the problem of making it difficult to understand the content of the call.

Purpose of the Invention The present invention is intended to solve the problems of the prior art, and its purpose is to switch between transmitting and receiving by voice without requiring manual press talk operation. To provide a voice press-talk device which does not have the risk of returning to a reception mode even if the voice is interrupted during transmission and does not cause the beginning of the conversation to be interrupted.

Embodiment of the Invention FIG. 1 shows the configuration of an embodiment of the voice press talk device of the present invention, together with the configuration of a personal radio to which it is applied. In the figure, 1 is a microphone, 2 is an amplifier, 3 is a pre-emphasis circuit, 4 is an IDC circuit, 5 is an amplifier, and 6 is a
PLL synthesizer, 7 is a transmission/reception switching circuit, 8 is a transmitter, 9 is a power amplifier, 10 is an APC circuit, 1
1 is an antenna switch, 12 is a low-pass filter, 13 is an antenna, 14 is a receiving section, and 15 is a first
intermediate frequency amplifier, 16 is a second intermediate frequency amplifier, 1
7 is a discriminator, 18 is a low frequency amplifier,
19 is a speaker, 20 is a keyboard, 21 is a controller, 22 is a group code display, 23 is a press talk switch, 24 is a band pass filter, 2
5 is an amplifier, 26 is a one-shot multi, 27 is an analog switch, 28 is a voice recognition device, and 29 is a photocoupler.

Also, FIG. 2 shows the signals of each part in FIG. 1,
In particular, the operation of the voice press talk device of the present invention will be explained. In the figure, is the output of the bandpass filter 24, is the output of the amplifier 25,
is the output of the one-shot multi 26, is the operation of the analog switch 28, is the operation of the voice recognition device 28, and is the transmission/reception switching pulse, and these are indicated by the same numbers at corresponding positions in FIG. ing.

In the transmission mode, the audio input from the microphone 1 (see Figure 2) is amplified as required by the amplifier 2, and then sent to the pre-emphasis circuit 2.
The signal is added to the signal and receives pre-emphasis necessary for FM modulation according to predetermined characteristics, and is further subjected to instantaneous distortion suppression control in the IDC circuit 4, and is added to the amplifier 5 to receive the required amplification. The PLL synthesizer 6 has a voltage controlled oscillator VCO, and by applying the output of the amplifier 5 as a control voltage,
Generates a frequency-modulated high-frequency signal according to audio input. When the transmission/reception switching circuit 7 is switched to the transmission state, this signal is passed through the transmission section 8.
The signal is added to the output signal, receives the necessary amplification, and is further amplified to a predetermined output level in the power amplifier 9.
The APC circuit 10 detects the output level of the power amplifier 9 and controls the output level of the power amplifier 9 to be maintained at a predetermined value by, for example, controlling the base bias of the output transistor in the power amplifier 9. . When the antenna switch 11 is in the transmitting state, the output of the power amplifier 9 is applied to the low-pass filter 12 to remove high frequency components, and then supplied to the antenna 13.

In the reception mode, the reception input to the antenna 13 passes through the low-pass filter 12 and the antenna switch 11 which is switched to the reception state, is applied to the reception section 14, undergoes high frequency amplification, and is then applied to the first intermediate frequency amplifier 15. . When the PLL synthesizer 6 and the transmission/reception switching circuit 7 are switched to the receiving state, the output of the PLL synthesizer 6 is applied as a local signal to the first intermediate frequency amplifier 15, and this and the built-in crystal oscillator output are applied to the first intermediate frequency amplifier 15. The received signal is then converted to a first intermediate frequency and subjected to the required amplification. The second intermediate frequency amplifier 16 converts the first intermediate frequency signal into a second intermediate frequency using the output of a built-in crystal oscillator, and further amplifies the signal. Discriminator 17
demodulates the second intermediate frequency signal to reproduce an audio signal, and this signal is amplified as required in the low frequency amplifier 18 and then supplied to the speaker 19.

The frequency to be used for transmission and reception is designated by a group code on the keyboard 20. The controller 21 thereby displays the group code on the group code display 22, determines the frequency division ratio N of each transmission/reception state in the PLL synthesizer 6 according to the specified group code, and sets this to the PLL synthesizer 6.
Output to synthesizer 6.

When the PLL synthesizer 6 receives the designation of the frequency division ratio from the controller 21, the PLL synthesizer 6 generates a phase-locked loop.
A carrier wave signal is synthesized using a PLL based on a fixed frequency signal from an internal crystal oscillator. The frequency of the carrier wave is different during transmission and reception, and is configured to be a transmission carrier wave during transmission and a reception local signal during reception.

Press talk switch 23 on keyboard 20
is connected, and each time it is turned on, a transmission/reception switching pulse is output, and the controller 21 inverts the transmission/reception switching signal every time a pulse is input, thereby switching between the transmission mode and the reception mode. The press talk switch 23 is usually provided integrally with the microphone 1.

The audio signal output from the amplifier 2 passes through a bandpass filter 24 to remove noise in the high and low ranges (FIG. 2). The amplifier 25 amplifies and clips the audio signal from the bandpass filter 24 to the saturation region, and further smooths it with a fixed time constant using a built-in integration circuit. Therefore amplifier 25
As an output, a signal is obtained that is at a high level while audio is being input, and becomes a low level when the audio is no longer input (Figure 2).

The one-shot multi 26 is triggered by the rise of the output of the amplifier 25, and is activated for a certain period of time (T
(Fig. 2). The analog switch 27 is turned on when the pulse of the one-shot multi 26 is applied (Fig. 2).
As a result, the analog switch 27 passes only the beginning part of the speech input for T seconds and inputs it to the speech recognition device 28 .

The voice recognition device 28 operates when it receives voice input from the analog switch 27 (FIG. 2).
When the speech recognition device 28 receives a word that matches a pattern in which speech patterns corresponding to several predetermined terms consisting of two groups are registered, it identifies this and generates an output. When the photocoupler 29 receives the identification output from the voice recognition device 28, it is turned on and generates a transmission/reception switching pulse on its output side. The output side of the photocoupler 29 is connected in parallel with the press talk switch 23, so that when the controller 21 receives a pulse, it inverts the transmission/reception switching signal in the same way as when the press talk 23 is operated.

Terms (keywords) to be registered in the voice recognition device 29 include, for example, words such as "yes" or "understood" that are normally used to notify the other party of the start of transmission as the first group, and words such as "yes" or "understood" that are usually used to notify the other party of the start of transmission, and words as the second group. You can use words such as "please" that are used to notify the end of transmission,
By pronouncing these terms during the first T seconds of a message, the operator can switch the transmission/reception mode in the same way as when using a press-talk switch. However, the words in the second group, such as "please" that signal the end of transmission, are used to ensure that the one-shot multi 26 operates correctly.
It is desirable that the sound be emitted some time after the end of the transmission.

In FIG. 1, if the controller 21 is constructed so that it can be operated directly by the identification output of the voice recognition device 28, it goes without saying that switching between transmission and reception can be performed without using the photocoupler 29.

Effects of the Invention As explained above, according to the voice press talk device of the present invention, a pulse of a certain length is generated by being triggered by the rising edge of a transmitted message, and when this pulse is generated, a plurality of specific The speech recognition device identifies the terms of the first group and generates an output, and when the first group of terms generates the identification output, it controls the transmitting mode, and the second group of terms identifies the output. When this occurs, control is performed to switch to receive mode, so it is possible to switch between transmit and receive modes by voice without requiring manual press talk operations. This is extremely effective because there is no risk of returning to the listening mode due to the call, and there is no possibility that the beginning of the conversation will be cut off.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the voice press talk device of the present invention, and FIG. 2 is a time chart showing signals of various parts in FIG. 1...Microphone, 2...Amplifier, 3...Pre-emphasis circuit, 4...IDC circuit, 5...Amplifier, 6...
PLL synthesizer, 7...transmission/reception switching circuit, 8...
Transmission section, 9...Power amplification section, 10...APC circuit, 1
DESCRIPTION OF SYMBOLS 1... Antenna switch, 12... Low pass filter, 13... Antenna, 14... Receiving part, 15... First
Intermediate frequency amplifier, 16...Second intermediate frequency amplifier, 1
7...Discriminator, 18...Low frequency amplifier,
19...Speaker, 20...Keyboard, 21...Controller, 22...Group code display, 23...Press talk switch, 24...Band pass filter, 2
5...Amplifier, 26...One shot multi, 27...
Analog switch, 28...Voice recognition device, 29...
Photocoupler.

Claims (1)

[Claims] 1. In a half-duplex type transmitting/receiving device that includes a transmitting section and a receiving section and switches the transmitting/receiving mode by a press talk operation, means for generating a pulse of a fixed time length triggered at the rising edge of a transmitted message; voice recognition means for identifying a plurality of specific terms in the voice when a pulse is generated and generating an output; and when an identification output based on a term of the first group is generated, the apparatus is set to a transmission mode and selects a term of the second group; 1. A voice press-talk device characterized in that a transmitting/receiving device is controlled to enter a receiving mode when an identification output is generated.