JPH06343059A - Optical fiber parallel type transmitting device - Google Patents

Abstract

PURPOSE:To economically shape the waveform in each optical fiber without using any monitor line that is exclusively used for setting the threshold value by using one of those signals obtained by applying the photoelectric conversion to the outputs of plural optical fibers for detection of the threshold value and then using the detection output as the threshold value of each comparator. CONSTITUTION:A photoelectric converter 4 converts the optical signal 1-n of an optical fiber 1 into electric signals via an optical input terminal 3 of a receiving optical device 2. These electric signals are supplied to the input terminals A of comparators 5. The output of a converter 4 (n) is supplied to a threshold value detecting circuit 6, and the detection output of the circuit 6 is supplied to each input terminal B as the threshold value signal of each comparator 5. Then each comparator 5 decides the logical value of the input electric signal of the terminal A based on the input threshold value signal of the terminal B and then performs the waveform shaping. Furthermore the circuit 6 can easily detect the threshold value of the input optical signal of the converter 4(n) since this signal has its mark rate of about 0.5 and also a satisfactorily high quenching ratio. Thus the economical waveform shaping is attained without using any monitor line exclusive for setting the threshold value nor a light emitter and a light receiver.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical transmission device for transmitting signals in parallel using a plurality of optical fibers to transfer data, and a threshold value of a signal received from the optical fibers. The present invention relates to an optical fiber parallel type transmission device capable of accurately shaping a received signal by detecting a signal.

[0002]

2. Description of the Related Art As a conventional technique of this kind, Japanese Patent Application Laid-Open No. HEI-2
According to this document, a conventional optical fiber parallel type transmission apparatus has an optical output of a light emitting element by changing the length of an optical fiber used or by using for a long period of time. The threshold value on the receiving side is not set for each signal line and each signal control line due to the fluctuation of the level.In addition to the signal line and the signal control line, a separate monitor line for setting the threshold value is provided. It is designed to facilitate the setting of threshold values.

That is, at least one of the plurality of optical fibers to be used is set as a monitor signal transmission line for monitoring the arrival level of an optical signal, and the other optical fibers are set as data transmission lines. The monitor signal transmitted through the monitor signal transmission line is amplified by an amplifier provided corresponding to the monitor signal transmission line, and is then arranged in a one-to-one correspondence with the plurality of data transmission lines. Input as a reference value to each comparator in the receiving circuit.

The data signal transmitted through each data transmission line is input to each comparator after being amplified by each amplifier in the receiving side circuit, and the reference signal is input to the comparator. The value was used to compensate the output signal level from the comparator. As described above, in the conventional optical fiber transmission device, all of the plurality of optical fibers used for data transmission are not used as data transmission lines, but at least one optical fiber is used as a monitor signal transmission line. The compensation of the output signal level from was secured.

[0005]

However, in the above-mentioned conventional technique, at least one of the signal line and the signal control line to be processed for the original information transmission should be the monitor line for setting the threshold value. Therefore, it is necessary to specially provide a monitor line unrelated to the signal line and the signal control line. Therefore, by providing the threshold setting monitor line by this separate line, it is necessary to also provide a light emitting device or a light receiving device corresponding to the monitor line, which is a cause of increasing the size and cost of the device. Was there.

The present invention has been made in order to solve the above-mentioned problems, and makes it possible to set a threshold value without using a threshold value setting monitor line by a separate line, and to provide a signal line and a signal control line. It is an object of the present invention to provide an optical fiber parallel type transmission device which is suitable for cost reduction by reducing the number of unrelated monitor optical fiber lines and the number of light emitters and light receivers corresponding to the monitor lines. It is what

[0007]

In order to achieve the above-mentioned object, the present invention transfers data by transmitting signals in parallel using a plurality of optical fibers, and at the same time, from each of these optical fibers. In an optical fiber parallel transmission apparatus for detecting a threshold value of a received signal and shaping the waveform of the received signal, one of the plurality of optical fibers is provided with a threshold of a signal output from each of the optical fibers. It is also used as a threshold value detection signal line for detecting a value, and an optical signal from one optical fiber used as the threshold value detection signal line and other optical fibers for data transmission is used. The optical signal is converted into an electric signal by an opto-electric converter provided corresponding to each of the optical fibers, and the electric signal is input to a comparator provided corresponding to each of the optical fibers,
Moreover, the electric signal converted from the optical fiber used as the threshold value detection signal line is input to the threshold value detection circuit for detecting the threshold value in addition to being input to the comparator, and the threshold value is detected. By inputting the output signal from the value detection circuit into each of the comparators as a threshold value, the comparator determines the logical value of the input signal, and the waveform of each of the optical fibers is shaped. Is.

Further, in the optical fiber parallel type transmission apparatus for performing waveform shaping and waveform regeneration of the received signal of the optical fiber, one of the plurality of optical fibers is output from each of the optical fibers. A clock signal line synchronized with other optical signals for detecting the threshold value of the signal is used, and the optical fiber used as the clock signal line for this threshold value detection and the other optical fibers for data transmission The optical signal is converted into an electric signal by an opto-electric converter provided corresponding to each of the optical fibers, and the electric signal is input to a comparator provided corresponding to each of the optical fibers, and, The electric signal of the clock signal line for detecting the threshold value is input to the threshold value detecting circuit for detecting the threshold value in addition to being input to the comparator, By inputting the output signal to each of the comparators as a threshold value, the logical value of the input signal is determined by each of the comparators, the waveform of each of the optical fibers is shaped, and the output of each of the comparators is performed. A waveform shaping signal corresponding to each of the comparators is input to the plurality of waveform reproducing circuits, and a waveform shaping signal from one comparator corresponding to the clock signal line for threshold value detection is input to each of the plurality of waveform reproducing circuits. By inputting to the waveform shaping circuit, the waveform of each optical fiber for data transmission is reproduced.

[0009]

With the above configuration, the optical signal from each optical fiber is input to each opto-electric converter in the receiving side optical device,
Here, the optical signal is converted into an electric signal and input to the corresponding comparator. At this time, the optical signal of the optical fiber used as the threshold value detection signal line is similarly converted into an electric signal and input to the corresponding comparator, but at the same time, this electric signal is input to the threshold value detection circuit, Here, the threshold value is detected. Since the threshold detection signal input to the threshold detection circuit is a signal having a substantially constant signal mark ratio, the threshold can be easily detected.

The threshold value detected by the threshold value detection circuit is input to each of the comparators, the comparator determines the logical value (0/1), and is input as a reference value for data transmission. Performs waveform shaping of the electronic signal of.
Further, when performing waveform reproduction together with this waveform shaping, the waveform shaping signals obtained by the plurality of comparators are
The signals are input to a plurality of waveform reproduction circuits provided corresponding to other comparators except the comparator corresponding to the threshold value detection signal among the comparators.

Then, the waveform shaping signal obtained from the comparator corresponding to the threshold value detecting signal is inputted to each of the plurality of waveform reproducing circuits. As a result, the signals from all the optical fibers for data transmission are regenerated in the waveform regenerating circuit.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. 1 is a configuration diagram showing an embodiment of the present invention, FIG. 2 is an explanatory diagram showing a threshold detection circuit, and FIG. 3 is an explanatory diagram of a frame signal input to a threshold detection signal line. In the figure, reference numerals 1 (1) to 1 (n) denote a plurality of optical fibers for transmitting optical information. The plurality of optical fibers 1 (1)
Threshold value for detecting the threshold value of the signal output from each of the optical fibers 1 (1) to 1 (n-1) of one of the optical fibers 1 (n) to 1 (n) The detection signal line and the other fibers 1 (1) to 1 (n-1) are used for data transmission.

Reference numeral 2 denotes a receiving side optical device for receiving signals from each of the optical fibers 1 (1) to 1 (n), and a plurality of optical devices corresponding to the optical fibers 1 (1) to 1 (n), respectively. The optical fiber 1 is equipped with a plurality of optical input terminals 3 (1) to 3 (n).
(1) to 1 (n) are connected to the optical input terminals 3 (1) to 3 (n), respectively. In the receiving side optical device 2, a plurality of opto-electric converters 4 (1) to 4 (n) respectively associated with the optical fibers 1 (1) to 1 (n) and the optical fibers A plurality of comparators 5 corresponding to the electric converters 4 (1) to 4 (n)
(1) to 5 (n), and the plurality of optical fibers 1 (1)
Threshold detection circuit for obtaining an output signal from one of the optical fibers 1 (n) to 1 (n) and outputting threshold signals to the comparators 5 (1) to 5 (n) 6 is provided.

As can be seen, each optical fiber 1 (1)
~ 1 (n) are the optical input terminals 3 (1) of the receiving side optical device 2 respectively
To 3 (n), the optical input terminals 3 (1) to 3 (n) are connected to the input terminals of the opto-electric converters 4 (1) to 4 (n), respectively, and the opto-electric conversion is performed. The output terminals of the devices 4 (1) to 4 (n-1) are connected to the input terminals A of the comparators 5 (1) to 5 (n-1), respectively.

The output terminal of one photoelectric converter 4 (n) among the photoelectric converters 4 (1) to 4 (n) is connected to the input terminal A of the comparator 5 (n) as described above. It is connected to both of the input terminals C of the threshold value detection circuit 6, and the output terminal D of the threshold value detection circuit 6 is connected to each input terminal B of the comparators 5 (1) to 5 (n). In the above configuration, the optical signals from the optical fibers 1 (1) to 1 (n-1) are first input to the optical input terminals 3 (1) to 3 (n-1), and the optical input terminals 3 (1) to 3 (n-1) are input. (1) to 3 (n-1) are input to the photoelectric converters 4 (1) to 4 (n-1) in the optical device 2 on the receiving side, and the photoelectric converters 4 (1) to 4 (1) are input. .About.4 (n-1) converts the optical signal into an electric signal and inputs the signal to the input terminal A of the comparators 5 (1) to 5 (n-1).

The comparators 5 (1) to 5 (n-1)
Is an electric signal inputted from each photoelectric converter 4 (1) to 4 (n-1) to the input terminal A by a threshold signal inputted from the threshold detection circuit 6 to the input terminal B. Logical value (0
This is a circuit for making the judgment of / 1) and shaping the waveform of the electronic signal inputted to the input terminal A. On the other hand, optical fiber 1
Since (n) is the threshold value detection signal as described above, an optical signal with a mark ratio of about 0.5 due to scrambling or the like and a sufficiently high extinction ratio is output to the optical input terminal 3 (n).
Is input to the optical-electrical converter 4 (n) in the optical device 2 on the receiving side through the optical input terminal 3 (n), and an optical signal is input by the optical-electrical converter 4 (n). Is converted into an electric signal. The electric signal converted by the opto-electric converter 4 (n) has a signal mark ratio of approximately 0.5, so that the threshold value detection circuit 6 can easily detect the threshold value.

The threshold value detected by the threshold value detection circuit 6 is input to the input terminal B of each of the comparators 5 (1) to 5 (n), and the comparators 5 (1) to 5 (n) output light. The logical value (0/1) of the electric signal converted by the electric converters 4 (1) to 4 (n) is determined, and the waveform is shaped. Also,
The optical signal input to the optical input terminal 3 (n) from the optical fiber 1 (n), which is the signal line for detecting the threshold value, has a signal mark ratio of 0. It can also be realized by using a CMI code of 5 or a clock line.

That is, as shown in (1) of FIG. 2, the threshold detection circuit 6 removes the DC component from the input signal by a capacitor and then converts it into a DC signal by a full-wave rectifying circuit and a smoothing circuit. A method of detecting the threshold value of the input signal by integrating with an integrating circuit as shown in (2),
As shown in (3), the method of detecting the threshold value by detecting the peak of the input signal by the peak detection circuit can be applied. Therefore, as in the case of the frame signal often seen in the communication device as shown in FIG. If the signal mark ratio is 0 or 1 instead of 0.5 and it is regarded as almost constant, the threshold detection circuit 6 detects the threshold value as (2) or (3) in FIG. Is possible.

Next, another embodiment will be described with reference to FIG. FIG. 4 is a constitutional view showing another embodiment, in which optical fibers 1 (1) to 1 (n) and an optical input terminal 3 (1) are shown.
.About.3 (n), photoelectric converters 4 (1) to 4 (n), comparators 5 (1) to 5 (n), and threshold value detection circuit 6 are substantially the same as those in the above-mentioned embodiment, and Since it is configured in the same way,
The same reference numerals are given and the description thereof is omitted.

7 (1) to 7 (n) are the optical fibers 1 (1) to
1 (n) is a plurality of waveform reproducing circuits provided in the receiving side optical device 2 and receives the electric signals converted by the comparators 5 (1) to 5 (n), and at the same time, the comparator 5
It is a circuit that receives the output signal from (n) and reproduces the waveform. According to the above configuration, the optical signals from the optical fibers 1 (1) to 1 (n-1) are input to the respective optical input terminals 3 (1) to 3 (n-1), Input terminal 3 (1)
To 3 (n-1) to the photoelectric converters 4 (1) to 4 (n-1) in the optical device 2 on the receiving side, and the photoelectric converters 4 (1) to 4 (1) to
The input signal is converted from an optical signal to an electrical signal at 4 (n-1), and the comparator 5 (1) becomes an electrical signal.
It is input as a reference value to each input terminal A of .about.5 (n-1).

On the other hand, from the optical fiber 1 (n) which is the signal line for detecting the threshold value, a clock signal synchronized with other signals for data transmission is inputted to the optical input terminal 3 (n), The clock signal is input from the optical input terminal 3 (n) to the opto-electric converter 4 (n) in the receiving side optical device 2, and the opto-electric converter 4 (n)
At (n), the optical signal is converted to an electronic signal. At this time, since the electric signal converted by the photoelectric converter 4 (n) is a clock signal and the signal mark ratio is 0.5,
The threshold value detection circuit 6 can easily detect the threshold value.

The threshold value detected by the threshold value detecting circuit 6 is input to the input terminal B of each of the comparators 5 (1) to 5 (n), and the comparators 5 (1) to 5 (n) are optically connected. The electric signals converted by the electric converters 4 (1) to 4 (n) are subjected to waveform shaping. The electric signal waveform-shaped by the comparators 5 (1) to 5 (n-1) is input to the input terminal A of the waveform reproduction circuits 7 (1) to 7 (n), while the comparator 5 (n) The waveform-shaped electric signal is sent to the waveform reproduction circuit 7 (1) -7 (7).
It is input to the input terminal B of (n).

Since the electric signal whose waveform has been shaped by the comparator 5 (n) is a clock signal which is synchronized with other signals, the waveform reproducing circuits 7 (1) to 7 (n) make the comparator 5 (1) ) It becomes possible to reproduce the waveform of the output signal of 5 (n-1).

[0024]

As described above, according to the present invention, one of a plurality of optical fibers is used for detecting the threshold value of the signal output from each of the optical fibers. An opto-electrical device which is also used as a detection signal and which is provided with one optical fiber as the detection signal and optical signals from each of the other optical fibers for data transmission corresponding to each of the optical fibers. While converting into an electronic signal by the converter, this electric signal is input to the comparator provided corresponding to each of the optical fibers, and the electric signal converted from the optical fiber for the threshold detection signal. Is
By inputting it to a corresponding comparator and a threshold value detection circuit for detecting a threshold value, and inputting the threshold value detected by the threshold value detection circuit to each of the comparators, Then, the logical value of the input signal is determined, and the waveform of each optical fiber is shaped.

For this reason, the monitor line conventionally provided for detecting the threshold value is not required, so that the light emitting device and the light receiving device which are required by providing the monitor line are also unnecessary, and as a result, It is possible to obtain an effect that it is possible to realize a small-sized optical fiber parallel type transmission apparatus which is suitable for economy. Further, as a second item, a waveform reproducing circuit connected to the output terminal of the comparator is provided in an arrangement corresponding to the optical fiber for data transmission, and the waveform shaping signal output from each comparator is associated with each comparator. The data transmission is performed by inputting the waveform shaping signal from one comparator corresponding to the clock signal line for threshold value detection to each of the plurality of waveform shaping circuits while inputting to the plurality of waveform reproducing circuits. Waveform reproduction of each optical fiber for use was performed. As described above, when the threshold detection signal line is used as the clock signal, the waveform reproduction can be easily and accurately realized because it is synchronized with the other data transfer signals.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a circuit example in a threshold detection circuit.

FIG. 3 is an explanatory diagram of a frame signal input to a threshold detection signal line.

FIG. 4 is a configuration diagram showing another embodiment of the present invention.

[Explanation of symbols]

 1 Optical Fiber 2 Optical Device on Receiving Side 3 Optical Input Terminal 4 Photoelectric Converter 5 Comparator 6 Threshold Detection Circuit 7 Waveform Regeneration Circuit

Claims (5)

[Claims] 1. A data signal is transferred by transmitting a signal in parallel using a plurality of optical fibers, and a received signal threshold value from each of these optical fibers is detected to shape the waveform of the received signal. In the optical fiber parallel transmission apparatus for performing the above, one of the plurality of optical fibers is used as a threshold value detection signal line for detecting a threshold value of a signal output from each of the optical fibers. An optical-electrical converter provided with an optical signal from the one optical fiber used as the threshold value detection signal line and from each of the other optical fibers used for data transmission corresponding to each optical fiber. The electric signal is converted into an electric signal by the optical fiber, and the electric signal is input to the comparator provided corresponding to each of the optical fibers, and the electric signal converted from the optical fiber used as the threshold detection signal line. Is input to a threshold value detection circuit for detecting a threshold value in addition to being input to the comparator, and an output signal from the threshold value detection circuit is input to each of the comparators as a threshold value. An optical fiber parallel transmission device, wherein each comparator determines the logical value of the input signal to perform waveform shaping of each optical fiber. 2. The optical line according to claim 1, wherein a signal line for threshold value detection of a plurality of optical fibers is a signal line having a signal mark ratio of about 0.5 by scrambling. Fiber parallel transmission device. 3. The optical fiber parallel type transmission apparatus according to claim 1, wherein a frame synchronization signal having a substantially constant signal mark ratio is used as the threshold value detecting signal line of the plurality of optical fibers. . 4. A clock line in which a threshold value detecting signal line of a plurality of optical fibers is synchronized with a signal line of another optical fiber used for data transmission is used. Optical fiber parallel type transmission equipment. 5. The data transfer is performed by transmitting signals in parallel using a plurality of optical fibers, and the waveform of the received signals is shaped by detecting the threshold value of the received signals from each of these optical fibers. Also, in the optical fiber parallel transmission apparatus for performing waveform reproduction, one of the plurality of optical fibers is used as another optical signal for detecting a threshold value of a signal output from each of the optical fibers. Optical signals from the synchronized clock signal line and the clock signal line for detecting the threshold value and the other optical fibers for data transmission are provided for each optical fiber. The electrical signal is converted into an electrical signal by the optical-electrical converter, and the electrical signal is input to the comparator provided corresponding to each of the optical fibers, and the clock signal line for detecting the threshold value is supplied. The electric signal is input to a threshold detection circuit for detecting a threshold in addition to being input to the comparator, and an output signal from the threshold detection circuit is input to each of the comparators as a threshold, The logical value of the input signal is determined by each of the comparators, the waveform of each of the optical fibers is shaped, and the waveform shaped signal output from each of the comparators is converted into a plurality of waveforms corresponding to each of the comparators. By inputting the waveform shaping signal from one comparator corresponding to the threshold value detecting clock signal line to each of the plurality of waveform reproducing circuits while inputting to the waveform reproducing circuit, An optical fiber parallel type transmission device characterized by performing waveform regeneration of an optical fiber.