JPH0828675B2 - Wireless communication system - Google Patents

Description

TECHNICAL FIELD The present invention relates to a wireless communication system for transmitting and receiving a voice signal and a data signal via a wireless line.

[Prior Art] Generally, in wireless data communication using a wireless device for communication, impedance matching of transmission / reception signals is established in a connection between the wireless device and a terminal device, and a microphone is connected during communication, while data is transmitted. At the time of communication, an interface device for switching to connect the terminal device is required. In this case, since a general communication radio does not have a dedicated terminal for connecting to the terminal device, the transmission signal of the terminal device is connected to the microphone terminal of the radio device and the reception signal from the radio device is It is taken out from the earphone terminal and connected to the terminal device.

By the way, the proper level of the received signal to be input to the terminal device is set to a constant value for each device. Since the signal level of the earphone terminal of the wireless device can be adjusted with the volume control knob, the knob can be adjusted to an appropriate level on the terminal device side.

However, when the wireless device is also used for a call, the volume is arbitrarily adjusted according to the situation at the time of the call, especially when data is frequently transmitted from the other party between calls. Each time data was received, the terminal device had to be readjusted to an appropriate signal level, and the operation was troublesome.

In addition, when the operator becomes absent after adjusting the signal level for data after the call, there is a problem that the data transmitted during the absence cannot be received.

[Object] In view of the above points, an object of the present invention is to provide a wireless communication system that can reliably receive data without adjusting the received signal level of the wireless device.

[Configuration] The present invention relates to a wireless communication system for transmitting and receiving a voice signal and a data signal via a wireless line, and a receiving unit for receiving a signal transmitted via the wireless line and a received signal level of the received signal. Adjusting means for adjusting in multiple stages, audio output means for outputting an acoustic signal corresponding to an input audio signal, a data processing device for executing predetermined data processing based on the input data signal, and an audio signal At the time of reception, the received signal level adjusted by the adjusting means is input to the audio means, and an acoustic signal having a volume corresponding to the received signal level is output, while at the time of receiving a data signal, a predetermined value is obtained regardless of the adjustment of the adjusting means. The signal level is output to the data processing device.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram of a wireless communication system according to an embodiment of the present invention. In the figure, a keyboard / printer 1 is for inputting command information to a partner radio station while recording character information transmitted from the partner station, and is a modem 2 for converting a transmitted / received digital signal into a voice band signal. And a wireless device 4 which is used for both telephone communication and data communication via an interface device 3.

A microphone stand 5 to which a microphone 5a and a press talk switch 5b are attached is connected to the interface device 3.

The wireless device 4 can be used as a normal communication wireless device by connecting the microphone stand 5 by itself. For this purpose, a transmission signal terminal for connecting a microphone and a transmission / reception switching signal terminal for connecting a press talk switch are used. , A reception signal terminal for connecting an external speaker. The wireless device 4 is connected to the interface device 3 through these terminals.

Although not shown, in the partner radio station communicating with this radio station, a computer is connected to such various devices instead of the terminal device in this radio communication system to form a radio communication system.

FIG. 2 shows a block diagram of this wireless communication system. In the figure, the frequency discriminating circuit 4a in the radio 4 receives a signal extracted from a receiver (not shown).
It demodulates an FM modulated wave into a reception signal in the voice band,
The received signal is input to the amplifier circuit 4c via the variable resistor 4b for volume control. The amplifier circuit 4c amplifies the received signal and outputs it from the speaker 4d. The squelch circuit 4e uses the amplifier circuit 4c when there is no received wave from the other station.
The circuit operation of is stopped to prevent noise from being output from the speaker 4d.

The amplifier circuit 4f amplifies the received signal and outputs it at a constant signal level, and the switch circuit 4g includes the amplifier circuit 4c.
One of the outputs 4 and 4f is selected and output from the reception signal terminal 4h. The carrier wave detection circuit 4i detects the carrier wave of the partner station modem which is received during data transmission in the reception signal in the voice band output from the frequency discrimination circuit 4a, and switches and controls the switch circuit 4g.

The reception signal output from the reception signal terminal 4h is the impedance matching circuit for the speaker 3a on the interface device 3 side.
It is entered in 3b. The output of the impedance matching circuit 3b is input to the demodulation circuit 2a of the modem 2. Demodulation circuit 2a
Is for demodulating the received signal which is a modulated analog signal into a digital data signal, and the demodulated data signal is input to the printer 1a of the keyboard printer 1. The printer 1a records character information on recording paper.

On the other hand, the keyboard 1b is for inputting command information,
The transmission data signal output as a digital signal from the keyboard 1b is input to the modulation circuit 2b of the modem 2. The modulation circuit 2b modulates the transmission signal into an analog signal in the voice band, and the modulated transmission data signal is input to the AGC circuit 3d via the impedance matching circuit 3c of the interface device 3. The AGC circuit 3d suppresses and stabilizes the level fluctuation of the transmission data signal, and this output is input to the contact D side of the switch circuit 3e, and the switch circuit 3e
Is switched to the D side, the data signal is transmitted through the common terminal of the switch circuit 3e to the transmission signal terminal of the radio device 4.
Input to radio 4 from 4j.

In the radio 4, the input transmission signal is amplified by the amplification circuit 4k.
The input and amplified transmission signal is input to a transmission circuit that wirelessly transmits by FM modulation (not shown).

The keyboard 1b also outputs a transmission / reception switching signal as a contact signal. This signal is the OR circuit 3f of the interface device 3.
The output of the OR circuit 3f is input to the wireless device 4 through the transmission / reception switching signal terminal 4l. The input transmission / reception switching signal is input to a control circuit (not shown) that switches the wireless device 4 between the transmitting state and the receiving state.

The ground lines of the above devices are commonly connected.

On the other hand, the ground line of the microphone 5a is connected to the interface device 3
Is connected to the ground line of the other and the other line is a switch circuit
It is connected to the C side terminal of 3e. Further, one line of the press talk switch 5b is similarly connected to the ground line, and the other line is input to the switch circuit 3e which uses the contact signal as a control signal and the OR circuit 3f.

In the wireless communication system of the present embodiment having the above configuration, when a call is made with the partner station, the FM modulated and transmitted voice signal is demodulated by the frequency discrimination circuit 4a and taken out. This voice signal does not include the carrier wave of the modem which is received at the time of data reception.
Does not detect the carrier wave, and the switch circuit 4g is connected to the C side.

Therefore, the received voice is output from both the speaker 4d on the radio device 4 side and the speaker 3a on the interface device side. The volume at this time can be arbitrarily adjusted by the variable resistor 4b.

On the other hand, when transmitting, the voice is input from the microphone 5a while turning on the press talk switch 5b. When the press talk switch 5b is turned on, the switch circuit 3e is switched to the C side by the contact signal, and the wireless device 4 enters the transmitting state. Therefore, the voice input from the microphone 5a is input to the amplification circuit 4k, and the output thereof is input to the transmission circuit (not shown) and transmitted to the partner station.

In this way, the call with the partner station can be made by the normal operation method. Further, in this case, since the speaker 3a in the interface device 3 can receive a voice, there is no problem even if the wireless device 4 is away from the interface device 3 and the microphone stand 5.

On the other hand, when sending a command to the computer of the partner station, predetermined command information is input to the keyboard 1b. By this operation, the keyboard 1b outputs the inputted command information to the modulation circuit 2b as transmission data, while the transmission / reception switching signal which is a contact signal is turned on during the transmission data output period. This transmission / reception switching signal is input to the wireless device 4 via the OR circuit 3f, and the wireless device 4 enters the transmitting state.

At this time, since the switch circuit 3e is connected to the D side, the transmission data output from the keyboard 1b is modulated by the modulation circuit 2b, the signal level is stabilized by the AGC circuit 3d, and is transmitted via the switch circuit 3e. It is input to the wireless device 4. Since the wireless device 4 is now in the transmitting state, the transmission data, which is the command information modulated into the voice band signal, is further FM-modulated and wirelessly transmitted to the partner station.

In response, the information of the computer from the other station,
It is modulated and transmitted in the same manner as above. The wireless device 4 receives this, demodulates it into a signal in the voice band from the frequency discriminating circuit 4a, and outputs a received data signal.

At this time, since the received data signal is a signal modulated by the modem of the partner station, for example, CCITT Recommendation V.23 1
For a 200 baud modem, the carrier is a 1700 ± 400 Hz signal. The carrier wave detection circuit 4i switches the switch circuit 4g to the D side when detecting the carrier wave of such a specific frequency.

The amplifier circuit 4f amplifies the received data signal to a set constant level and outputs it. The amplified received data signal is input to the demodulation circuit 2a via the impedance matching circuit 3b. The demodulation circuit 2a demodulates the input reception data signal into a digital signal and outputs it to the printer 1a. Printer
1a records various information transmitted from the computer of the partner station by this received data signal.

By the way, in order to operate the demodulation circuit 2a normally,
The received data signal must be input at a fixed level determined.

In this case, the variable resistor 4b for volume adjustment during a call.
Is adjusted arbitrarily, and the signal level output from the reception signal terminal 4h becomes indefinite. However, since the switch circuit 4g is switched to the D side when receiving data as described above, the received data signal is always output from the amplifier circuit 4f at a constant level.

Therefore, the output signal level of the amplifier circuit 4f is set to the demodulation circuit 2a.
By setting an appropriate signal level for the demodulator 2a, the demodulator 2a always operates normally, and the printer 1a can reliably receive the received information.

In this way, the telephone call and the data communication can be used together, and it becomes unnecessary to adjust the level of the received signal one by one when performing the data communication.

On the other hand, as is clear from the above description, in the wireless device 4 alone, if the microphone 5a is connected to the transmission signal terminal 4j and the press talk switch circuit 5b is connected to the transmission / reception switching signal terminal 4l together with the ground line, a normal telephone call can be made. It can be used as a radio. At this time, needless to say, if an external speaker is connected to the reception signal terminal 4h, the volume can be adjusted arbitrarily.

As described above, according to the present embodiment, the reception signal terminal 4h of the wireless device 4 outputs the reception voice signal whose signal level is adjusted by the volume adjusting variable resistor 4b during a call, and is always output during the data communication. The received data signal is output at a constant signal level. As a result, it is not necessary to adjust the received signal level one by one during data communication, and information can always be received reliably.

In this embodiment, the reception signal whose signal level is adjusted by the variable resistor 4b and the reception signal whose signal level is fixed are switched by the switch circuit 4g. When the variable resistor 4b
Of course, other means such as overriding the action of may be used. Further, the switching of the signal level by the switch circuit 4g is performed by detecting the carrier wave of the received signal, but a signal indicating that the signal is being received is taken out from the terminal device and the switching is performed by the signal. You may do it.

[Effect] As described above, according to the present invention, in a wireless communication system that transmits and receives a voice signal and a data signal via a wireless line, a receiving unit that receives a signal transmitted via the wireless line, Adjusting means for adjusting the received signal level of the received signal in multiple stages, audio output means for outputting an acoustic signal corresponding to the input audio signal, and predetermined data processing based on the input data signal A data processing device and, when receiving a voice signal, inputs to the voice means at the received signal level adjusted by the adjusting means and outputs an acoustic signal having a volume corresponding to the received signal level, while at the time of receiving the data signal the above Since the data is output to the data processing device at a predetermined signal level regardless of the adjustment of the adjusting means, the received signal level of the radio can be adjusted. It is possible to obtain the effect that data can be reliably received.

[Brief description of drawings]

FIG. 1 is a device configuration diagram of a wireless communication system according to an embodiment of the present invention, and FIG. 2 is a block configuration diagram thereof. 1 ... keyboard printer, 1a ... printer, 1b ...
Keyboard, 2 Modem, 2a Demodulator, 2b Modulator, 3 Interface device, 3a, 4d Speaker, 3b, 3c Impedance matching circuit, 3d AGC circuit, 3e, 4g ...... Switch circuit, 3f …… OR circuit, 4 ……
Radio, 4a ... Frequency discrimination circuit, 4b ... Variable resistor, 4
c, 4f, 4k …… Amplification circuit, 4h …… Reception signal terminal, 4i …… Carrier detector, 4j …… Transmission signal terminal, 4l …… Transmission / reception switching signal terminal, 5 …… Microphone stand, 5a …… Microphone, 5b …… Press talk switch.

Claims (1)

[Claims] 1. In a wireless communication system for transmitting and receiving a voice signal and a data signal via a wireless line, a receiving means for receiving a signal transmitted via the wireless line and a multi-stage receiving signal level of the received signal. Adjusting means for adjusting to, an audio output means for outputting an acoustic signal corresponding to the input audio signal, a data processing device for executing predetermined data processing based on the input data signal, and The received signal level adjusted by the adjusting means is input to the audio means, and an acoustic signal of a volume corresponding to the received signal level is output, while a data signal is received, a predetermined signal regardless of the adjustment of the adjusting means. A wireless communication system which outputs the data to the data processing device at a level.