JPH1117634A - Voice multiplex transmission system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a voice multiplex transmission system by which a plurality of voices or control signals are sent in 2-way for a long range, without loss of a level through one transmission line. SOLUTION: This system consists of a transmitter 10 that converts a voice signal into transmission signal and transmits the converted signal, a cable transmission line through which the transmission signal is sent, and a receiver 20 that receives the transmission signal, converts it into a voice signal and provides an outputs of the voice signal. The transmitter 10 consists of a conversion section port 11, consisting of a plurality of ports 1-n, a port multiplexer section 12 connecting to the conversion section port 11, a transmission line transmission circuit 13 that is connected to the port multiplexer section 12 and the cable transmission line 5, and power supply circuits 14A, 14B that supply power to each section of the transmitter 10. Furthermore, the receiver 20 is connected to a transmission line reception circuit 23 connecting the cable transmission line 5, a port separate section 22 connecting to the transmission line reception circuit 23, a conversion section port 21 consisting of a plurality of ports 1-n and a power supply circuit 14 that supplies power supply to each section of the receiver 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a voice transmission apparatus for transmitting voice as a voice signal, and more particularly to a voice multiplex transmission apparatus for multiplexing and transmitting a plurality of voices.

[0002]

2. Description of the Related Art As a conventional voice transmission apparatus, Japanese Patent Laid-Open Publication No.
There is one disclosed in Japanese Patent Publication No. 350490. This audio transmission device includes a device on the control side, a device on the controlled side, and a single cable transmission line connecting them. The device on the control side has a remote fader, an A / D converter, a parallel / serial converter, and a conversion multiplexer. The controlled device includes a conversion multiplexing unit, a serial / parallel conversion unit, a D / A converter, a VCA mixer, and a microphone.

In the above configuration, a level control signal for each microphone on the controlled side is transmitted from the remote fader on the controlling side to the VCA mixer on the controlled side via a cable transmission line. The VCA mixer mixes the sound input from each microphone according to the level control signal, and transmits the mixed sound to the control side through a cable transmission path.

That is, in order to control the level of each microphone, the remote fader on the control side sends a DC voltage (analog data) corresponding to the level control to the A / D converter. The A / D converter converts the analog data into digital data for each channel and outputs the digital data to a parallel / serial converter. The parallel / serial converter converts the digital data into serial data and sends it to the conversion multiplexing unit. The multiplex conversion unit converts the serial data into a signal of 15 kHz when the serial data is at the H (high) level, and converts the signal into an intermittent wave signal with no signal (0) when the serial data is at the L (low) level, and transmits the signal to the cable transmission line.

[0005] On the controlled side, 15 k
Hz intermittent wave signal is obtained by a band pass filter,
It is sent to the conversion multiplexing unit. The conversion multiplexing unit converts the 15 kHz signal into H and the 0 kHz signal into L serial data and sends them to the serial / parallel converter. The serial / parallel converter converts the serial data into digital data for each channel and sends the digital data to the D / A converter. D
The / A converter converts digital data into analog data and sends it to the VCA mixer. The VCA mixer controls the sound level of each microphone according to the received analog data.

[0006] With this level control, the VCA mixer adjusts the volume of each microphone and mixes the volume of each microphone to obtain one mixed audio signal. The VCA mixer sends this mixed audio signal directly to the conversion multiplexing unit. The conversion multiplexing section converts the received mixing audio signal into a signal used for control.
The band of kHz is removed by the band elimination filter and transmitted to the cable transmission line.

On the control side, the conversion multiplexing unit receives the mixed audio signal from which the control signal of the 15 kHz band has been removed from the cable transmission line by the band-pass filter,
Send it to an audio output device (such as an output amplifier).

In order to supply power to the controlled side,
Connect the DC power supply directly to the cable transmission line on the control side.

As described above, according to the conventional audio multiplex transmission apparatus, the audio level control signal can be transmitted from the control side to the control side by one cable transmission line, and the audio level control signal is mixed from the control side to the control side. Can be sent, and power can be supplied from the control side to the controlled side.

Another conventional audio transmission apparatus is disclosed in Japanese Patent Laid-Open No. Hei 7-226701. This audio transmission device is composed of a device on the control side, a device on the controlled side, and a single balanced transmission line that is a shielded two-wire cable connecting them. The device on the control side has a remote fader, an A / D converter, a parallel / serial converter, and a demultiplexer. The controlled device includes a demultiplexer, a serial / parallel converter, a D / A converter,
It has a VCA mixer and a microphone. Further, the demultiplexing unit has a buffer amplifier, a transformer having a middle tap for grounding, and two resistors respectively corresponding to two lines of the balanced transmission line.

In the above configuration, a level control signal for each microphone on the controlled side is transmitted from the remote fader on the controlling side to the VCA mixer on the controlled side through a balanced transmission line. The VCA mixer mixes the sound input from each microphone according to the level control signal,
The signal is transmitted to the control side through a balanced transmission path.

That is, in order to control the level of each microphone, the remote fader on the control side sends a DC voltage (analog data) corresponding to the level control to the A / D converter. The A / D converter converts the analog data into digital data for each channel and outputs the digital data to a parallel / serial converter. The parallel / serial converter converts digital data into serial data and sends it to the demultiplexing unit. The multiplex conversion unit superimposes serial data in phase on two lines of a direct balanced transmission line via a buffer amplifier and two resistors, and transmits the superimposed serial data.

On the controlled side, only the serial data of the positive phase is extracted from the balanced transmission line by the buffer amplifier of the conversion multiplexing unit and sent to the serial / parallel converter. The serial / parallel converter converts the serial data into digital data for each channel and sends the digital data to the D / A converter. The D / A converter converts digital data into analog data and sends it to the VCA mixer. The VCA mixer controls the sound level of each microphone according to the received analog data.

With this level control, the VCA mixer adjusts the volume of each microphone and mixes the volume of each microphone to obtain one mixed audio signal. The VCA mixer sends this mixed audio signal directly to the demultiplexing unit. The conversion multiplexing unit transmits the received mixed audio signal in a positive phase to one line of the balanced transmission line and in an opposite phase to the other line via a transformer of an intermediate tap for grounding.

On the control side, the demultiplexing unit receives the positive-phase and negative-phase mixed audio signals from the balanced transmission line, and converts the mixed audio signals into the original mixed audio signals via the transformer of the grounding intermediate tap. To an audio output device (such as an output amplifier).

In order to supply power to the controlled side,
Connect the DC power supply directly to the balanced transmission line on the control side.

As described above, according to the conventional audio multiplex transmission apparatus, the audio level control signal can be sent from the control side to the control side by one balanced transmission line, and the audio level control signal is mixed from the control side to the control side. Audio signal, and power can be supplied from the control side to the controlled side.

In the audio transmission apparatus disclosed in Japanese Patent Application Laid-Open No. Hei 7-226701, the cable transmission path of the audio transmission apparatus disclosed in Japanese Patent Application Laid-Open No. 6-350490 is a balanced transmission path. Since the signal is transmitted, external noise with respect to the transmission path is reduced, and the unusable band (15 kHz) for transmitting the audio signal for the control signal is eliminated.

[0019]

However, according to the conventional voice multiplex transmission apparatus as disclosed in JP-A-6-350490 and JP-A-7-226701,
Since the mixed audio signal, which is the original audio signal, is directly transmitted, there is a problem that a plurality of individual audio signals cannot be transmitted simultaneously.

In the audio transmission apparatus disclosed in Japanese Patent Application Laid-Open No. Hei 6-350490, since 15 kHz of the signal band is allocated to the frequency of the control signal, the audio signal in the 15 kHz frequency band cannot be transmitted. Further, in order to solve this problem, according to the audio transmission apparatus disclosed in Japanese Patent Application Laid-Open No. Hei 7-226701, there is a problem that a transformer is required due to the use of a balanced transmission line, so that the circuit scale becomes considerably large.

Further, according to the conventional voice multiplex transmission apparatus,
Since the audio signal is transmitted on the transmission line, the audio signal is degraded due to cable loss in the transmission line, and there is a problem that the audio level cannot be transmitted accurately.

In addition, since the power supply from the control side to the control side is limited to the remote device including only the serial / parallel conversion unit, the D / A converter, and the VCA mixer on the control side, the power supply from the control side to the control side is limited. There is a problem that power cannot be supplied to remote peripheral devices such as a microphone and a head amplifier on the control side.

Further, in the transmission of audio data, there is a problem that only unidirectional transmission from the controlled side to the control side is possible, and that bidirectional transmission between the control side and the controlled side is not possible. Further, if DC power is not supplied from the battery on both the controlled side and the control side, and power supply or the like is interrupted during voice transmission, a system failure occurs.

Accordingly, an object of the present invention is to provide a voice multiplex transmission apparatus capable of transmitting a plurality of voices or control signals over a long distance in one direction without any level loss.

It is another object of the present invention to provide an audio multiplex transmission apparatus which can transmit audio signals in all frequency bands without increasing the circuit scale.

It is a further object of the present invention to provide an audio multiplex transmission apparatus capable of supplying power from a control side to a remote apparatus and a remote peripheral apparatus on a controlled side.

[0027]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention provides a transmission path from an audio output device for transmitting a plurality of audio signals to an audio input device for inputting a plurality of audio signals. In a voice multiplex transmission device that transmits a plurality of voice signals via a transmission device that transmits a plurality of voice signals from a voice output device, and a reception device that outputs a plurality of voice signals from the transmission device to a voice input device A transmitting device receives a plurality of audio signals from the audio output device and converts the plurality of audio signals into serial data respectively.
A plurality of ports having a plurality of conversion means, a plurality of ports receiving and multiplexing a plurality of serial data converted by the first conversion means from the plurality of ports, and multiplexed data from the port multiplexing section. Transmission line transmission means for transmitting to a transmission line, the reception device receiving the multiplexed data from the transmission line reception unit, receiving the multiplexed data from the transmission line, Port separating means for receiving a plurality of separated serial data, converting the plurality of serial data into a plurality of audio signals, and outputting a plurality of audio signals to an audio input device. And a plurality of ports having means.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A voice multiplex transmission apparatus according to the present invention will be described below in detail.

FIG. 1 shows an embodiment of a voice multiplex transmission apparatus according to the present invention. The audio multiplex transmission apparatus 1 converts a voice signal into a transmission signal and transmits the signal, a cable transmission path 5 for transmitting an electric signal from the transmission apparatus 10, and a transmission signal from the cable transmission path 5. The receiving device 20 converts the signal into a voice signal and outputs the signal. A sound output device 2 such as a mixer output, a head amplifier output, a power amplifier output, an intercom output, and a compact disk (CD) player output is connected to the transmission device 10 side of the audio multiplex transmission device 1 and connected to the reception device 20 side. Is connected to an audio input device 3 such as a mixer input, a head amplifier input, a power amplifier input, an intercom input, and a CD player input.

The transmission device 10 includes a conversion unit port 11 composed of a plurality of ports 1 to n, a port multiplexing unit 12 connected to the conversion unit port 11, a port multiplexing unit 12, and a transmission line transmission connected to the cable transmission line 5. Circuit 13 and transmitting device 1
And a power supply circuit 14A for supplying power to each of the device units 0. Each of the ports 1 to n of the converter port 11 is connected to the audio output device 2 by two microphone cables 30.

Each of the ports 1 to n of the converter port 11 has an A / D converter 15. The A / D converter 15 is connected to the audio output device 2 via the microphone cable 30 and converts the analog audio signal from the full scale setting unit 16 to a digital signal from the full scale setting unit 16 for setting the maximum amplitude level of the audio signal. A / D converter 1
7 and a data format unit 18 connected to the A / D converter 17 for formatting a digital signal.

The receiving device 20 is connected to the cable transmission path 5
Transmission line receiving circuit 23 connected with the transmission line receiving circuit 23
, A conversion unit port 2 connected to the port separation unit 22 and comprising a plurality of ports 1 to n
1 and a power supply circuit 14B for supplying power to each unit of the receiving device 20. Each of the ports 1 to n of the conversion unit port 21 is connected to the audio input device 3 by a two-channel microphone cable 30.

Each of the ports 1 to n of the converter port 21 has a D / A converter 25. The D / A conversion unit 25 is connected to the port separation unit 22, and separates the multiplexed audio signal into a data separation unit 28, a data separation unit 28
D / to convert digital audio signals from
It has an A-converter 27 and an output level setting unit 26 connected to the audio input device 3 via a D / A converter 27 and a microphone cable 30 to set an output level of an audio signal.

The power supply circuits 14A and 14B of the transmission device 10 and the reception device 20 have an AC power input and a DC power input, and can receive AC power and DC power.
Here, the DC power input is connected to a battery (not shown). When the power supply circuits 14A and 14B receive power supply from both AC power supply and DC power supply,
Prioritizing AC power supply, the transmitting device 10 or the receiving device 20
Power is supplied to each device inside. When the power supply from the AC power supply is interrupted due to a power failure or the like, the power supply circuits 14A and 14B are automatically switched to the DC power supply by the circuit configuration. This will be described in detail later.

In this configuration, transmission of an audio signal from the audio output device 2 to the audio input device 3 will be described. The audio output device 2 is connected to each of the ports 1 to n of the transmission device 10 via a two-channel microphone cable 30.
To send an audio signal. Each port 1 to n of the transmission device 10
A / D conversion unit 15 in the full scale setting unit 16
The transmitted audio signal is received from the two-channel microphone cable 30.

The full-scale setting section 16 converts the received audio signal into a full-scale audio signal having the maximum amplitude level that can be input to the A / D converter 17 and sends the signal to the A / D converter 17. The digital code of the full scale information indicating the level is sent to the data format unit 18. The A / D converter 17 converts the full-scale audio signal from the full-scale setting unit 16 from an analog signal to a digital signal, receives a synchronization signal and a clock from the port multiplexing unit 12, and converts the digital signal into audio serial data. I do. The generated audio serial data is sent from the A / D converter 17 to the data format unit 18. The data format unit 18 converts the audio serial data and the digital code received from the full scale setting unit 16 into serial data synchronized with another port by using a synchronization signal and a clock input from the port multiplexing unit 12. The data format part 18 of each port 1 to n
The serial data is transmitted to the port multiplexing unit 12 while being synchronized with the other ports by the synchronization signal and the clock input from the port multiplexing unit 12.

The port multiplexing unit 12 multiplexes n serial data input from each of the ports 1 to n into one serial data and transmits the serial data to the transmission line transmitting circuit 13. The transmission line sending circuit 13 converts one input serial data into a bi-phase code including clock information so as to synchronize with the transmission line receiving circuit 23 on the receiving device 20 side,
It is connected to a cable transmission line 5 by a driver (not shown).
Send to

The transmission line receiving circuit 23 of the receiving device 20 receives the bi-phase code via the cable transmission line 5 and amplifies the bi-phase code. The serial data from the transmission line receiving circuit 23 is sent to the port separation unit 22. Port separation unit 2
Reference numeral 2 denotes each port 1 of the conversion unit port 21 corresponding to each of the ports 1 to n on the transmitting device 10 side.
Ｎn (that is, a port on the receiving device 20 side having the same number as the port number on the transmitting device 10), and transmits the clock and a synchronization signal to each of the ports 1１〜n.

The data separation unit 28 in the D / A conversion unit 25 of each of the ports 1 to n separates the received serial data into audio serial data and a digital code of full-scale information set on the transmission device 10 side. Then, the audio serial data is sent to the D / A converter 27, and the digital code of the full scale information is sent to the output level setting unit 26. D /
The A-converter 27 converts the received audio serial data from a digital signal to an analog signal, and also converts the received audio serial data into a full-scale audio signal by a clock from the port separation unit 22. The full-scale audio signal generated by the D / A converter 27 is sent to the output level setting unit 26.
The output level setting unit 26 converts the full-scale audio signal received from the D / A converter 27 by the digital code of the full-scale information received from the data separation unit 28.
The audio signal is converted into an audio signal having the same amplitude level as the amplitude level input from the audio output device 2. Each of the ports 1 to n of the conversion unit port 21 transmits the audio signal to the audio input device 3 via a two-channel microphone cable 30.
Send to

As described above, a plurality of audio signals can be transmitted from the audio output device 2 to the audio input device 3 by one cable transmission 5.

Hereinafter, each unit in the transmitting device 10 and the receiving device 20 will be described in detail.

FIG. 2 shows the A / D converter 15 of the transmitting apparatus 10.
The details are shown below. The A / D converter 15 of the transmission device 10 includes a full scale setting unit 16, an A / D converter 17 for converting a balanced audio signal into audio serial data, and an A / D converter 1.
7 has a data format unit 18 for multiplexing the audio serial data from 7 and arranging them into one serial data.

The full scale setting section 16 includes two balanced / unbalanced converting sections 41 for converting a balanced voice signal into an unbalanced voice signal, n selectors 44 capable of arbitrarily changing the gain, and n gains. And two gain variable devices 4 for conducting only one path of the gain designated by the selector 44.
2, and two unbalanced / balanced conversion units 43 that are provided at the subsequent stage of the gain variable unit 42 and are connected to the A / D converter 17 and convert unbalanced audio signals into balanced audio signals.

From the two first and second channels, audio signals (balanced audio signals) are input to two balanced / unbalanced converters 41, respectively. The balance / unbalance conversion unit 41
The balanced audio signal is converted into an unbalanced audio signal so that it can be input to the variable gain device 42 and output to the variable gain device 42.
Here, since the audio signal is a balanced audio signal, the audio signal may have a waveform of a positive phase and a negative phase, and only the positive phase may be extracted to be an unbalanced audio signal. The conversion of a balanced audio signal into an unbalanced audio signal is achieved by converting a balanced audio signal into an unbalanced audio signal and setting the gain only for the positive phase. This is because the variable device 42 is sufficient.

The gain variable unit 42 selects only a path of an arbitrary gain from among the gains 1 to n by the selector 44 to determine the maximum amplitude level of the audio signal input from the two first and second channels. The A / D converter 17 converts the unbalanced audio signal into a full-scale audio signal in accordance with the maximum amplitude level that can be input. By this conversion, A / D
When the converter 17 converts an analog signal into a digital signal, there is no waste in quantization.

FIG. 3 shows the converted full-scale audio signal. As shown in FIG. 3A, the maximum amplitude level (input maximum scale) of the audio signals input from the two first and second channels is the maximum amplitude level that can be input to the A / D converter 17. In the case of a level smaller than (A / D full scale), if the input audio signal is quantized by the A / D converter 17 as it is, the quantization of the A / D converter 17 is as follows.
Since the audio signal is subdivided and digitized at the A / D full scale, the portions (1) and (2) of FIG. 3A are not used as a result. Therefore, if this is done, coarse quantization results, and as a result, voice quality deteriorates. In order to prevent the deterioration of the voice quality, the A / D is set by variably setting the maximum input amplitude level of the voice signal to the maximum amplitude level that can be input to the A / D converter 17 in advance.
The converter 17 can perform highly accurate quantization. Conversely, as shown in FIG. 3B, when the input maximum scale is larger than the A / D full scale, if the input audio signal is quantized by the A / D converter 17 as it is, the entire amplitude is quantized. Can not be converted. Therefore, the entire amplitude can be quantized by variably setting the maximum input amplitude level of the audio signal to the maximum inputtable amplitude level of the A / D converter 17.

In FIG. 2, the full-scale unbalanced audio signal converted by the gain variable unit 42 has an unbalanced / unbalanced sound signal.
The signal is converted into a full-scale balanced audio signal by the balanced conversion unit 43 and transmitted to the A / D converter 17. The A / D converter 17 converts the full-scale balanced audio signal into audio serial data by using the clock and the synchronization signal from the port multiplexing unit 12 (FIG. 1), and sends the digital audio data to the data format unit 18.

In order to convert the full scale information into a digital code, all the terminals of the selector 44 are connected to the ground via a resistor so that the digital code becomes 0. Next, the voltage of the selector 44 is increased to Vcc by a resistor, and the selected selector 44 is
The resistance voltage is set to a logic H level.
As a result, only the selected selector 44 is at the H level, and the selector 44 can select only one path of the gain variable device 42, and among the gains 1 to n in the gain variable device 42,
The digital code of the selected gain is output to the data format unit 18.

The data format section 18 converts the audio serial data from the A / D converter 17 and the digital code from the selector 44 into serial data and outputs the serial data to the port multiplexing section 12 (FIG. 1).

FIG. 4 shows a format of serial data output to the port multiplexing unit 12. The arrangement order of the data in the serial data is such that gain numbers 1 to n are added one bit at a time for each of the serial data of the first and second channels output by one sampling.

FIG. 5 shows details of the port multiplexing unit 12 shown in FIG. The port multiplexing unit 12 includes a dual port memory 51 for temporarily storing serial data from each of the ports 1 to n of the conversion unit port 11, a parallel / serial converter 52 for converting parallel data into serial data, and synchronizing serial data. Bi-phase coding unit 5 for converting into a bi-phase code including a clock signal to be enabled
3, a synchronizing signal and a clock for synchronizing the n serial data, a write address for writing the serial data to the dual port memory 51, and a read address for reading the serial data to the parallel / serial converter 52. , And a control signal for transmitting the control signal.

As shown in FIG. 5, a synchronization signal and a clock are sent from the controller 54 to each of the ports 1 to n of the converter port 11. Each port 1 of the conversion unit port 11
n receives these and sends out serial data synchronized with the arrangement to the dual port memory 51.

The dual port memory 51 receives serial data one bit at a time from each of the ports 1 to n of the conversion unit port 11 corresponding to the write address according to the write address from the controller 54. Next, the dual-port memory 51 converts the once stored serial data into parallel data in parallel / serial conversion at n times the writing speed (1 / n time) according to the read address from the controller 54. Output to the device 52.

FIG. 6 shows how data is converted by the parallel / serial converter 52. The parallel / serial converter 52 converts the parallel data into serial data again in order to receive the serial data from the dual port memory 51 in parallel. In this conversion, the parallel / serial converter 52 reads out the input serial data at a speed n times the input speed, so that the time series on the serial side and the parallel side match, and n consecutive serial data are converted into one. It can be multiplexed into pieces of serial data.

The signals (data) up to this point are NRZ (No.
ne Return to Zero) code, which is a digital signal of 1 or 0 having no clock component. This digital signal cannot be synchronized even if it is input to the port separation unit 22 (FIG. 1) of the receiving device 20 via the cable transmission line 5 as it is.

Therefore, in FIG. 5, the biphase coding unit 53 adds a clock component to the serial data input from the parallel / serial converter 52 and converts the serial data into a biphase code. That is, the bi-phase coding unit 53 sets the start point of the continuous bi-phase code to the port separating unit 22 (FIG. 1) of the receiving device 20.
, A bi-phase code rule violation is added at a fixed period to the start point of the bi-phase code, and is output to the transmission line transmission circuit 13 (FIG. 1).

FIG. 7 shows an NRZ code and two types of biphase codes. The type of the two biphase signals is determined depending on whether the first bit is 1 or 0.

FIG. 8 shows the transmission line sending circuit 13 in detail when the cable of the cable transmission line 5 is a multi-core cable. In FIG. 8, the transmission line transmission circuit 13
Has a cable driver 61 and a pulse transformer 62 for transmitting a bi-phase code in positive and negative differential phases.

Cable driver 6 of transmission line sending circuit 13
1 receives the bi-phase code from the port multiplexing unit 12 and outputs normal-phase and negative-phase data to the pulse transformer 62. The pulse transformer 62 sends the bi-phase code to the two pairs of twisted wires 64 of the multi-core cable 63, which is the cable transmission line 5, as positive-phase data and reverse-phase data, respectively.

In this manner, the transmission line sending circuit 13 connected to the cable transmission line 5 is insulated, and the transmission line sending circuit 13 and the cable transmission line 5 can be prevented from being adversely affected by the ground loop. 5 can be avoided by the common mode removal function.

FIG. 9 shows the transmission line sending circuit 13 in detail when the cable of the cable transmission line 5 is an optical fiber cable. The transmission line sending circuit 13 has an E /
An O / Electric / Opto unit 71, a PIN photodiode 72, and a laser diode 73 are provided. E / O part 7
1 is a driver 76 for driving the laser diode 73
APC that monitors the optical power and keeps the optical power constant
(Automatic Power Control) circuit 75. still,
The laser diode 73 is an LED (Light Emitting Dio
de).

The driver 76 of the E / O unit 71 receives the bi-phase code from the port multiplexing unit 12 and supplies a current corresponding to the amplitude of the bi-phase code to the laser diode 73. As a result, the biphase code is electro-optically converted and sent to the optical fiber cable 74 of the cable transmission line 5.

On the other hand, the APC circuit 75 of the E / O unit 71
The laser light emission power is monitored by the PIN photodiode 72. When the light emission power is low, the drive current of the driver 76 is increased, and when the light emission power is high, the drive current of the driver 76 is reduced. The light output to 5 is kept constant.

FIG. 10 shows in detail the transmission line receiving circuit 23 of the receiving device 20 when the cable of the cable transmission line 5 is a multi-core cable. 10, the transmission line receiving circuit 23 includes a pulse transformer 62 connected to the twisted pair wire 64 of the cable transmission line 5 and a line receiver 65.

The pulse transformer 62 includes a transmission line sending circuit 1
3 is received via the cable transmission line 5. Here, the pulse transformer 6
2 transmits only the bi-phase code to the line receiver 65 without blocking the DC component on the cable transmission line 5 side and transmitting it to the line receiver 65. As a result, it is possible to avoid an adverse effect due to a ground loop between the cable transmission line 5 and the transmission line receiving circuit 23.

The line receiver 65 receives the differential bi-phase code via the pulse transformer 62, shapes the waveform, and outputs it to the port separation unit 22 (FIG. 1).

FIG. 11 shows in detail the transmission line receiving circuit 23 of the receiving device 20 when the cable of the cable transmission line 5 is an optical fiber cable 74. 11, a transmission line receiving circuit 23 includes a PIN photodiode 72 for receiving an optical signal, a current / voltage converter 77 connected to the PIN photodiode 72, and a current / voltage converter 77.
, An amplifier 78 and a line receiver 65 connected at the subsequent stage.

The PIN photodiode 72 receives the optical signal from the optical fiber cable 74 of the cable transmission line 5 at a light modulation intensity corresponding to logic 1, 0 or 0, 1 of the blinking light, and receives the strong light. The current / voltage converter 7
7 so that no current flows when light is weak.

The current / voltage converter 77 receives the current from the PIN photodiode 72, converts it into a voltage, and sends it to the amplifier 78. The voltage at this point is a fairly small signal. The amplifier 78 amplifies the small voltage signal and sends it to the line receiver 65. The line receiver 65 shapes the waveform of the amplified voltage signal and outputs it to the port separation unit 22 (FIG. 1).

FIG. 12 shows the details of the port separating unit 22. In FIG. 12, a port separation unit 22 includes a PLL (Phase Locked Loop) 81 for extracting a clock from a biphase code from the transmission line receiving circuit 23, a header extraction unit 82 for detecting a start point of a data frame,
Biphase / N for converting biphase code to NRZ
An RZ conversion unit 83, a FIFO unit 84 having n FIFOs (First-In-First-Out) 86 for storing only serial data of each of the ports 1 to n, and a controller 85 for controlling the FIFO unit 84 are provided.

The PLL 81 extracts a clock from the biphase code input from the transmission path receiving circuit 23,
A header extraction unit 82, a biphase / NRZ conversion unit 83,
And the controller 85.

The header extracting unit 82 detects a biphase coding rule violation added at a fixed period to the start point by the port multiplexing unit 12 of the transmitting device 10 and notifies the controller 85 of the violation. By this notification, the controller 85 gives the n FIFOs 86 of the FIFO unit 84 a
The bi-phase / NRZ conversion unit 83 supplies a write clock for allocating the designated NRZ data.

FIG. 13 shows the generation timing of the write clock. As shown in FIG. 13, this write clock is
It is generated only at the timing of the NRZ data to enter the FIFO 86 specified by the controller 85.
This occurs periodically.

In FIG. 12, bi-phase / NRZ conversion section 83 converts the bi-phase code to NRZ
After converting the data into data, each FIFO 86 in the FIFO unit 84
And send it out. Each FIFO 86 of the FIFO unit 84 temporarily stores the NRZ data. The NRZ data stored in each FIFO 86 is read at a speed of 1 / n times the write clock from the controller 85 after making a round of the header of the serial data. As a result, the read N
The RZ data is converted into serial data output from the A / D conversion unit 15 of the transmission device 10 and is converted by the conversion unit port 2
1 to the respective ports 1 to n (FIG. 1). The controller 85 outputs a synchronization clock and a synchronization signal to each of the ports 1 to n of the converter port 21 (FIG. 1).

FIG. 14 shows each port 1 of the conversion unit port 21.
3 shows in detail the D / A conversion unit 25 included in. In FIG. 14, a D / A conversion unit 25 separates the serial data from the port separation unit 22 into audio serial data and a digital code, and converts the audio serial data from a digital signal to an analog audio signal. D / A converter 27 and output level setting unit 26
Having. The output level setting unit 26 is provided with a gain variable unit 42 for returning the audio signal to the original gain using a digital code.
And an unbalanced / unbalanced voice signal that converts an unbalanced voice signal into a balanced voice signal.
And a balance converter 43.

The data separation unit 28 receives the serial data from the port separation unit 22 and separates the serial data into audio serial data and n digital codes by using a synchronization signal and a clock.
The separated audio serial signal is sent to the D / A converter 27, and the n digital codes are sent to gains 1 to n of the gain variable unit 42, respectively.

The D / A converter 27 converts audio serial data from a digital signal to an analog audio signal in accordance with a synchronization signal and a clock. The gain variable device 42 is the same as that described with reference to FIGS.
To an audio signal having the same amplitude as the output level from The unbalanced / balanced conversion unit 43 converts the unbalanced audio signal from the variable gain unit 42 into a balanced audio signal and outputs the signal to the audio input device 3 via the microphone cable 30.

FIG. 15 shows the details of the power supply circuit 14. The power supply circuit 14 includes an AC / DC for supplying AC power.
Converter 91, reference circuit 92 for detecting the output voltage of AC / DC converter 91, switch (SW) 93 for conducting DC input, a plurality of diodes 9
5, 99, and a DC / DC converter 94.
Note that the SW 93 may be an electronic switch or a relay switch. The reference circuit 92 includes a reference voltage section (REF) 96, a resistor voltage divider 97, and a level comparison circuit 9.
8

In FIG. 15, the power supply 14 (14A, 14
B) AC power supply (AC IN) and DC power supply (DC
IN). The AC power is input to the AC / DC converter 91. When the input of these two systems of power supply is performed simultaneously, the output from the AC / DC converter 91 (AC power supply)
Has priority. That is, the reference circuit 92 outputs AC /
The DC output voltage from the DC converter 91 and the DC output voltage from the DC power supply are supplied via the diode 95 without interfering with each other's power supply. Reference circuit 92
The level comparison circuit 98 detects and compares the input voltage from the resistor voltage divider 97 and the input voltage from the REF 96 on the DC power supply side. Here, when the output voltage value from the AC / DC converter 91 falls below the output voltage value from the REF 96, the level comparison circuit 98 generates an output signal, and
By controlling W93, the DC / DC converter 94 is immediately conducted to the DC power supply side. Accordingly, the input voltage of the DC / DC converter 94 does not fluctuate and the D / D converter 94
It can be switched to the C feed input.

FIG. 16 shows another embodiment of the voice multiplex transmission apparatus of the present invention. FIG. 16 shows a configuration in which the audio multiplex transmission apparatus 1 shown in FIG. 1 is used for bidirectional audio transmission. This two-way audio multiplex transmission apparatus 40 is obtained by connecting two transmission / reception apparatuses 29 having the same configuration via the cable transmission line 5. The transmission / reception device 29 includes the transmission device 10 shown in FIG.
A port multiplexing unit 12 and a transmission line transmission circuit 13 of the reception device 20, a port separation unit 22 and a transmission line reception circuit 23 of the reception device 20,
And a conversion unit 31 including ports 1 to n having both functions of the conversion unit port 11 of the transmission device 10 and the conversion unit port 21 of the reception device 20. Each of the ports 1 to n of the conversion unit 31 is connected to the audio input / output device 32 by a microphone cable 30 of two channels.

Each of the ports 1 to n of the conversion unit 31 receives a synchronization signal and a clock from the port multiplexing unit 12, respectively.
The serial data to be transmitted to another transmitting / receiving device 29 is transmitted. Also, the ports 1 to n respectively transmit the synchronization signal, clock, and other transmission / reception devices 2 from the port separation unit 22.
9 is received. Converter 3
1 are connected to the A / D converter 15 shown in FIG.
And a D / A conversion unit 25, wherein the A / D conversion unit 15 enables voice transmission, and the D / A conversion unit 25 enables voice reception.

That is, since the transmission direction of the audio signal is changed at the ports 1 to n having the same port number of the respective transmission / reception devices 29, two-way transmission of the audio signal between the two transmission / reception devices 29 is possible. Thus, the transmission / reception device 29 of the two-way audio multiplex transmission device 40 can be connected to both the audio input device and the audio output device via the microphone cable 30.

FIG. 17 shows another embodiment of the voice multiplex transmission apparatus of the present invention. The bidirectional audio multiplex transmission device 50 of FIG.
Indicates that the A / D conversion unit 15 and the D / D conversion unit
The control signal converter 33 is provided in place of the / A converter 25. Each port 1 of the transmitting / receiving device 29a (left side in the figure)
The control signal converters 33 of the ports 1 to n of the transmission / reception device 29b (the right side in the drawing) are connected to the control device 34 via the multi-core cable 80. Is connected to the controlled device 35 via the.
The control signal converter 33 includes a waveform shaping unit 36, a synchronization circuit 3
7 and a line driver 38. The control signal converter 33 enables transmission and reception of control signals between the control device 34 and the controlled device 35.

FIG. 18 shows the waveform shaping section 36 and the synchronization circuit 37. The waveform shaping unit 36 has a line receiver 65, and the synchronization circuit 37 is a flip-flop 45
Having.

The waveform shaping section 36 receives logic signals 1 and 0 from the control device 34. This logic signal has a level loss due to the length of the multi-core cable 80 or the like. For this reason, the line receiver 65 of the waveform shaping section 36 performs level reproduction of the received logic signal. The flip-flop 45 of the synchronization circuit 37 receives the synchronization signal and the clock, synchronizes the signal from the waveform shaping unit 36, converts the signal into serial data, and sends the serial data to the port multiplexing unit 12.

FIG. 19 shows the line driver 38. The line driver 38 converts the serial data output from the port separation unit 22 into differential signal control data, and sends the control data to the control device 34 or the controlled device 35 via the multi-core cable 80.

In FIG. 17, control data output from a control device 34 such as a remote controller is input to a waveform shaping section 36 of a control signal converter 33 in a transmitting / receiving device 29a via a multi-core cable 80. Waveform shaping unit 36
Reproduces the level of the control data attenuated by the multi-core cable 80 by the line receiver 65 and transmits it to the synchronization circuit 37. The synchronization circuit 37 synchronizes the control signal input asynchronously with the synchronization signal and the clock, and sends the control signal to the port multiplexing unit 12 as a serial signal.
As a result, the serial data is stored in the port type (FIG. 1).
16 and a common frame regardless of the A / D converter 15 and the D / A converter 25 shown in FIG. 16 and the control signal converter 33 shown in FIG.

In the transmission / reception device 29b, the port separation unit 22 divides the serial data received from the transmission / reception device 29a via the transmission line receiving circuit 23 into n pieces, and sends the divided data to the line drivers 38 of the ports 1 to n. The line driver 38 converts the received serial data into differential signal control data, and sends the control data to a controlled device 35 such as a head amplifier, a VCA mixer, or a fader via the multi-core cable 80.

By providing a control signal converter 33 at each of the ports 1 to n on both sides of the transmission / reception device 29a and the transmission / reception device 29b, transmission of control data from the controlled device 35 to the control device 34 can be performed in the same manner. And bidirectional transmission of control data becomes possible.

FIG. 20 shows another embodiment of the voice multiplex transmission apparatus of the present invention. The bidirectional audio multiplex transmission device 60 of FIG.
Is a device in which the transmitting / receiving device 29a of the two-way audio multiplex transmission device 50 shown in FIG. 17 is replaced with a host device 46 and the transmitting / receiving device 29b is replaced with a remote device 47. This is shown in FIG.
The two transmission / reception devices 29 of the two-way audio multiplex transmission device 40 shown in FIG. The host device 46 includes the transmitting / receiving device 2
9 and 29a are provided with a high-voltage power supply circuit 48.
Further, the remote device 47 includes the transmitting and receiving devices 29 and 29b.
And a high-voltage power receiving circuit 49. That is, the remote device 47 has three power supply inputs: AC power supply and DC power supply from the power supply circuit 19, and DC power supply from the high-voltage power receiving circuit 49. Further, the cable transmission line 5 has an optical camera composite cable or a multi-core cable for connecting the high-voltage power supply circuit 48 and the high-voltage power reception circuit 49.

FIG. 21 shows a high-voltage power supply circuit 48 at the time of AC input.
Is shown. The high-voltage power supply circuit 48 includes an AC
/ DC converter 91. This high-voltage power supply circuit 48
The AC / DC converter 91 receives an AC input, outputs a high-voltage DC, and supplies power to the cable transmission line 5.

FIG. 22 shows a high-voltage power supply circuit 48 at the time of DC input.
Is shown. The high voltage power supply circuit 48 is a DC
/ DC converter 94. This high-voltage power supply circuit 48
The DC / DC converter 94 receives a DC input, outputs a high-voltage DC, and supplies power to the cable transmission line 5.

FIG. 23 shows the cable transmission line 5 when an optical signal is applied. The cable transmission line 5 has an optical composite cable 55 including two optical fiber cables 74 a and 74 b and two power lines 56.

The optical fiber cable 74a transmits an optical signal from the transmission line sending circuit 13 on the host device 46 side to the transmission line receiving circuit 23 on the remote device 47 side. The optical fiber cable 74b transmits an optical signal from the transmission line sending circuit 13 on the remote device 47 side to the transmission line receiving circuit 23 on the host device 46 side. The power supply line 56 supplies power from the high voltage power supply circuit 48 of the host device 46 to the high voltage power receiving circuit 49 of the remote device 47.

FIG. 24 shows the cable transmission line 5 when an electric signal is applied. The cable transmission line 5 has a multi-core cable 57 including two twisted pair wires 64 a and 64 b and two power supply lines 56.

The twisted pair wire 64 a transmits a differential signal (electric signal) from the transmission line sending circuit 13 on the host device 46 side to the transmission line receiving circuit 23 on the remote device 47 side. The twisted pair wire 64b transmits a differential signal from the transmission line sending circuit 13 on the remote device 47 side to the transmission line receiving circuit 23 on the host device 46 side. The power supply line 56 supplies power from the high voltage power supply circuit 48 of the host device 46 to the high voltage power receiving circuit 49 of the remote device 47.

FIG. 25 shows a high-voltage power receiving circuit 4 at the time of DC input.
FIG. The high-voltage power receiving circuit 49 has a DC / DC converter 94. The high-voltage power receiving circuit 49 receives a high-voltage power supply from the cable transmission line 5, converts the high-voltage power supply into a low-voltage DC voltage by the DC / DC converter 94, and supplies the low-voltage DC voltage to the power supply circuit 19.
Power to

FIG. 26 shows a high-voltage power receiving circuit 4 at the time of AC input.
FIG. The high-voltage power receiving circuit 49 includes a DC / DC converter 94 and a DC / AC inverter 79. The high-voltage power receiving circuit 49 receives high-voltage power from the cable transmission line 5, converts the high-voltage power into a low-voltage DC voltage by the DC / DC converter 94, and supplies the low-voltage DC voltage to the power supply circuit 19. The high-voltage power receiving circuit 49 supplies the high-voltage power from the cable transmission line 5 with a DC / DC power.
The voltage is converted into an AC voltage by an AC inverter 79 and supplied to the audio input / output device 32 and the controlled device 35.

FIG. 27 shows the power supply circuit 19. The power supply circuit 19 includes an AC / DC converter 91, two reference circuits 92 and 39, and two SWs 93a and 9
3b, DC / DC converter 94, diodes 59, 9
9 That is, the power supply circuit 19 in FIG. 27 has two systems of the reference circuit 92 and the SW 93 of the power supply circuit 14 shown in FIG. Power receiving circuit 4
An input by DC power supply from 9 is added, and the reference circuit 39 is provided for DC power supply from the high-voltage power receiving circuit 49. Here, the reference circuits 92 and 39
Has a configuration similar to that of the reference circuit 92 shown in FIG. 15, and has a REF 96, a resistor voltage divider 97, and a level comparison circuit 98, respectively.

Referring to FIG. 27, AC / DC converter 9
1. The functions of the reference circuit 92 and the DC / DC converter 94 have the same functions as those of FIG. The reference circuit 39 receives power from the diode 59 and monitors the voltage level of the high-voltage power receiving circuit 49. When power is supplied from the high-voltage power receiving circuit 49, the switch 93
Since b is open, the output of the DC power supply from the high-voltage power receiving circuit 49 is supplied to the DC / DC converter 94 regardless of the presence or absence of the AC power supply (AC IN) and the DC power supply (DC IN).

When the DC power supply output from the high-voltage power receiving circuit 49 is lost, the reference circuit 39 switches to the SW 93b.
, And power is supplied to the DC / DC converter 94 from either the DC output voltage from the AC / DC converter 91 or the DC input. The control in this case is the same as that shown in FIG.

In FIG. 20, the host device 46 has a high-voltage power supply circuit 48 including an AC / DC power supply and a DC / DC power supply whose inputs and outputs are insulated. The high-voltage power supply circuit 48 can supply sufficient power to operate each device of the remote device 47 and its peripheral devices. High voltage power supply circuit 4
8 outputs power to the cable transmission line 5. Since the output voltage is a high voltage, the supply current is small, and even when the power of the remote device 47 is several hundred watts, the current is sufficient even in the optical composite cable 55 or the cable transmission line 5 of the multi-core cable 57. The capacity is in time. Further, by using a high voltage, the voltage drop in the cable transmission line 5 is reduced, and as a result, the host device 4
Even if the distance between the remote device 6 and the remote device 47 is long, power can be supplied from the host device 46 to the remote device 47. The high-voltage power receiving circuit 49 of the remote device 47 has a DC /
The high voltage is received by the DC converter 94 or the DC / AC inverter 79 and is converted into a stable DC voltage or AC voltage. The converted power is supplied to each unit of the remote device 47 and its peripheral devices, and the remote device 47 and its peripheral devices can be operated even when there is no power supply equipment on the remote device 47 side.

[0103]

As described above, according to the configuration of the voice multiplex transmission apparatus of the present invention, especially, the conversion unit ports 11, 21, the port multiplexing unit 12, the transmission line transmission circuit 1
3. Since the port separation unit 22 and the transmission path receiving circuit 23 are provided, the circuit scale is not increased, and
Long-distance transmission of audio signals and control signals, not only in one direction but also in two directions, can be transmitted over one cable transmission line 5 without level loss.

Further, by providing the high-voltage power supply circuit 48 and the high-voltage power reception circuit 49, power can be supplied to all devices on the remote device 47 side by power supply from the high-voltage power supply circuit 48.

Further, the power supply circuit 14
By providing the power supply, even if the power supply such as a power failure is interrupted on the AC power supply side, no system failure occurs during voice transmission. By making the signal on the transmission line an optical signal, distance and external noise can be avoided, and a ground loop between the devices can be avoided. Power can be supplied to the remote device with a single optical composite cable. Also, the host can remotely control the remote device facing the host.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a voice multiplex transmission apparatus of the present invention.

FIG. 2 is a block diagram illustrating details of an A / D conversion unit of the transmission device.

FIG. 3 is a diagram showing a converted full-scale audio signal.

FIG. 4 is a diagram showing a format of serial data output to a port multiplexing unit.

FIG. 5 is a block diagram illustrating details of a port multiplexing unit.

FIG. 6 is a diagram showing how data is converted by a parallel / serial converter.

FIG. 7 is a diagram illustrating an NRZ code and two types of biphase codes.

FIG. 8 is a diagram showing a transmission line sending circuit in detail when a cable of a cable transmission line is a multi-core cable.

FIG. 9 is a diagram showing in detail a transmission line sending circuit when a cable of a cable transmission line is an optical fiber cable.

FIG. 10 is a diagram showing in detail a transmission line receiving circuit of the receiving device when the cable of the cable transmission line is a multi-core cable.

FIG. 11 is a diagram illustrating in detail a transmission line receiving circuit of the receiving device when the cable of the cable transmission line is an optical fiber cable.

FIG. 12 is a block diagram illustrating details of a port separation unit.

FIG. 13 is a diagram showing the timing of generation of a write clock.

FIG. 14 shows D / D of each port 1 to n of the conversion unit port.
It is the block diagram which showed the A conversion part in detail.

FIG. 15 is a block diagram illustrating details of a power supply circuit.

FIG. 16 is a block diagram showing another embodiment of the voice multiplex transmission apparatus of the present invention.

FIG. 17 is a block diagram showing another embodiment of the voice multiplex transmission apparatus of the present invention.

FIG. 18 is a diagram illustrating a waveform shaping unit and a synchronization circuit.

FIG. 19 is a diagram illustrating a line driver.

FIG. 20 is a block diagram showing another embodiment of the voice multiplex transmission apparatus of the present invention.

FIG. 21 is a diagram illustrating a high-voltage power supply circuit during AC input.

FIG. 22 is a diagram showing a high-voltage power supply circuit at the time of DC input.

FIG. 23 is a diagram illustrating a cable transmission path when an optical signal is applied.

FIG. 24 is a diagram showing a cable transmission line when an electric signal is applied.

FIG. 25 is a diagram showing a high-voltage power receiving circuit at the time of DC input.

FIG. 26 is a diagram showing a high-voltage power receiving circuit at the time of AC input.

FIG. 27 illustrates a power supply circuit.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 audio multiplex transmission device 2 audio output device 3 audio input device 5 cable transmission line 10 transmission device 11, 21 conversion unit port 12 port multiplexing unit 13 transmission line transmission circuit 14 power supply circuit 22 port separation unit 23 transmission line reception circuit 29 transmission / reception device 30 microphone cable 48 high-voltage power supply circuit 49 high-voltage power reception circuit

Claims (12)

[Claims] An audio multiplex transmission device for transmitting a plurality of audio signals via a transmission path from an audio output device for transmitting a plurality of audio signals to an audio input device for inputting a plurality of audio signals, A transmitting device that transmits the plurality of audio signals from the device; and a receiving device that outputs the plurality of audio signals from the transmitting device to the audio input device. A plurality of ports having first conversion means for receiving the plurality of audio signals from the device and converting each of the plurality of audio signals into serial data; and the plurality of ports being converted by the first conversion means from the plurality of ports. Port multiplexing means for receiving and multiplexing the plurality of serial data, and transmission path transmitting means for transmitting the multiplexed data from the port multiplexing section to the transmission path. A transmission line receiving unit that receives the multiplexed data from the transmission line; a port separation unit that receives the multiplexed data from the transmission line reception unit and separates the multiplexed data into a plurality of serial data. A plurality of ports having second conversion means for receiving the separated plurality of serial data, converting the plurality of serial data into a plurality of audio signals, and outputting the plurality of audio signals to the audio input device; And a voice multiplex transmission device comprising: 2. The audio multiplex transmission apparatus according to claim 1, wherein said transmission apparatus and said reception apparatus have power supply means for supplying AC power and DC power, respectively. 3. The audio multiplex transmission apparatus according to claim 1, wherein said transmission apparatus and said reception apparatus each have power supply means for supplying AC power or DC power. 4. The transmission path sending means is an E / O circuit for converting an electric signal into an optical signal, and the transmission path receiving means comprises:
2. The audio multiplex transmission apparatus according to claim 1, wherein the O / E circuit converts an optical signal into an electric signal. 5. The A / D converter for converting the analog audio signal into audio serial data as a digital signal, the first conversion means, the audio output device and the A / D converter. Connected between
Full scale setting for receiving the plurality of audio signals from the audio output device, setting the amplitude of the audio signal to the full scale amplitude of the A / D converter, and outputting a gain code of the full scale information 2. The audio multiplex transmission apparatus according to claim 1, further comprising: means for receiving the audio serial data from the A / D converter, and multiplexing the audio serial data to generate the serial data. 6. The balanced / unbalanced conversion means for converting the audio signal, which is an unbalanced audio signal, into a balanced audio signal, and a gain of the balanced audio signal of the balanced / unbalanced conversion means. Changing the selector to specify an unbalanced audio signal; a gain variable device that outputs the unbalanced audio signal specified by the selector; and converting the unbalanced audio signal from the gain variable device to a balanced audio signal. And the unbalanced output to the A / D converter /
6. The voice multiplex transmission apparatus according to claim 5, comprising: a balance conversion unit. 7. The second converting means includes: data separating means for separating the serial data into audio serial data and a gain code; and converting the separated audio serial data, which is a digital signal, according to the gain code. A D / A converter for converting an analog signal having an audio input level into an analog audio signal, and output level setting means for adjusting an output level of the converted audio signal and outputting the adjusted audio signal to the audio input device. The audio multiplex transmission apparatus according to claim 1, wherein: 8. The transmission device according to claim 1, wherein the transmission device includes the transmission line receiving unit and the port separation unit, and the reception device includes the transmission line transmission unit and the port multiplexing unit. Voice multiplex transmission equipment. 9. The sound signal is a control signal, wherein the first and second converting means are: a waveform shaping means for adjusting amplitude levels of the plurality of received control signals; and the amplitude level is adjusted. 2. The audio multiplex transmission apparatus according to claim 1, further comprising: a synchronization unit that synchronizes the plurality of control signals to convert the serial data into serial data; and a line driver unit that converts the serial data into control data. 10. The transmitting apparatus has a high-voltage power supply for supplying high-voltage power to the receiving apparatus via the transmission line, and the receiving apparatus receives the high-voltage power from the high-voltage power supply. 2. The audio multiplex transmission apparatus according to claim 1, further comprising a high-voltage power receiving means for receiving the audio signal. 11. The port separation means comprises: PLL means for extracting a clock from the serial data; header extraction means for detecting a start point of a data frame of the serial data; and serial data which is a bi-phase code. Bi-phase / NRZ conversion means for converting the data into NRZ data; FIFO means having a plurality of FIFOs for storing the serial data for the plurality of ports; and control means for controlling the FIFO means. The audio multiplex transmission device according to claim 1. 12. The transmitting apparatus has high voltage power supply means for supplying high voltage power to the reception apparatus, wherein the reception apparatus receives high voltage power from the high voltage power supply means; Power supply means for supplying an AC power supply and a DC power supply; the power supply means on the receiving device side; a first power supply input means for inputting a DC voltage from the high voltage power receiving means; A second power input means having input means and a DC input means for inputting a DC voltage from a battery; an AC / DC converter for converting an AC voltage from the AC input means into a DC voltage; A first switch that switches between the first power input means and the second power input means;
A first reference circuit for controlling a switch of the first power supply; and a power supply input from the second power supply input means.
The audio multiplex transmission device according to claim 1, further comprising: a second switch that switches between input means and the DC input means; and a second reference circuit that controls the second switch. .