JP3395502B2 - Optical transmission device, optical transmission device, optical receiving device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to wavelength division multiplexing (WD) for wavelength-multiplexing and transmitting a plurality of optical signals in one optical fiber.
M) The present invention relates to an optical transmission device.

[0002]

2. Description of the Related Art A wavelength division multiplexing (WDM) optical transmission system for wavelength-multiplexing a plurality of signals and transmitting them by one optical fiber is
Many have been proposed in the past. 18 and 19 show, for example, "Fiber-Optic Communication Systems, GOVING P. AG.
It is a conventional wavelength division multiplexing optical transmission system described in RAWAL, pp274. FIG. 18 shows a conventional wavelength division multiplexing optical transmission system 1
FIG. 19 is a configuration diagram showing an example, and FIG. 19 is a configuration diagram showing another example of the conventional wavelength division multiplexing optical transmission system. Hereinafter, each will be described separately.

In FIG. 18, 1A is a wavelength division multiplexing optical transmitter, 1B is a wavelength division multiplexing optical receiver, 2A and 2B are electrical signals transmitted from 1A to 1B, 3A and 3B are electrical / optical wavelengths λ1 and λ2, respectively. Converters 4A and 4B are optical / electric converters having wavelengths λ1 and λ2, respectively, 5A and 5B are optical filters for extracting wavelengths λ1 and λ2, respectively, and 6A is a wavelength λ.
An optical coupler that multiplexes the optical signals 1 and λ2, an optical coupler 6B that splits the received optical signal, and a transmission line optical fiber 7A. The wavelength light transmitter 1A includes electric / optical converters 3A and 3B.
And an optical coupler 6A, and a wavelength light receiving device 1B
Is composed of optical filters 5A and 5B and an optical coupler 6B.

In FIG. 19, 1P is a wavelength division multiplexer, and 1P is a wavelength division multiplexer.
Q is a wavelength demultiplexer, and 18A and 18B are wavelength λ, respectively.
1 and λ2 are optical transmitters, 19A and 19B are optical receivers having wavelengths λ1 and λ2, respectively, and other reference numerals are the same as those in FIG. The wavelength multiplexer 1P is an optical coupler 6
The optical transmitters 18A and 18B are composed of electrical / optical converters 3A and 3B, respectively. The wavelength demultiplexer 1Q is composed of optical filters 5A and 5B and an optical coupler 6B, and the optical receivers 19A and 19B are composed of optical / electrical converters 4A and 4B, respectively.

Next, the operation of the conventional wavelength division multiplexing optical transmission system will be described. First, the operation of the conventional wavelength division multiplexing optical transmission system shown in FIG. 18 will be described. When the electric signals 2A and 2B are input to the wavelength division multiplexing optical transmitter 1A, the wavelength division multiplexing optical transmitter 1A converts the electric signals 2A and 2B into optical signals having wavelengths λ1 and λ2 by the electric optical converters 3A and 3B, respectively. Then, the optical signals of the wavelengths λ1 and λ2 are intensity-combined by the optical coupler 6A.
The output of the optical coupler 6A is connected to the transmission line optical fiber 7A, and the intensity-combined optical signal is transmitted to the transmission line optical fiber 7A.
Is output to.

In the wavelength division multiplexing optical receiver 1B, an optical signal that has passed through the transmission line optical fiber 7A is input to the optical coupler 6B and intensity distribution is performed, and then the optical filters 5A and 5B respectively perform wavelength λ.
The optical signals of 1 and λ2 are extracted and converted into electrical signals 2A and 2B in the photoelectric conversion units 4A and 4B. Then, the electric signals 2A and 2B are output from the wavelength division multiplexing optical receiver 1B.

Next, the operation of the conventional wavelength division multiplexing optical transmission system shown in FIG. 19 will be described. When the electric signals 2A and 2B are input to the optical transmitters 18A and 18B, respectively, the optical transmitters 18A and 18B transmit the electric signals 2A and 2B to the wavelength λ.
The optical signals of wavelengths λ1 and λ2 are intensity-combined by the optical coupler 6A in the wavelength multiplexer 1P. The output of the optical coupler 6A is connected to the transmission line optical fiber 7A, and the intensity-combined optical signal is output to the transmission line optical fiber 7A.

In the wavelength demultiplexer 1Q, an optical signal that has passed through the transmission line optical fiber 7A is input to the optical coupler 6B and intensity distribution is performed, and then the wavelengths λ1 and λ are respectively supplied to the optical filters 5A and 5B.
The optical signal 2 is extracted and output. The output optical signals are electric signals 2 in the optical receiving devices 19A and 19B, respectively.
Converted to A, 2B.

In the conventional transmission line optical fiber 7A in the conventional wavelength division multiplexing optical transmission system shown in FIGS.
Although the optical signal of No. 1 and the optical signal of wavelength λ2 propagate, mutual interference of the above two optical signals does not occur because the wavelengths are different, and good transmission quality can be obtained for each.

[0010]

In the conventional wavelength division multiplexing optical transmission system shown in FIG. 18, the input interface to the wavelength division multiplexing optical transmitter 1A and the wavelength division multiplexing receiver 1B are provided.
The output interface from was an electrical signal. Generally, electric signals are not suitable for long-distance transmission, and in the conventional system, the demultiplexed electric signals (2A and 2B in FIG. 18) should be distributed to the equipment installation station or a short distance area for communication. become. In such a conventional system, long-distance transmission can be performed only between the wavelength-multiplexing optical transmitter 1A and the wavelength-multiplexing optical receiver 1B, and the demultiplexed electric signal after the long-distance transmission is transmitted over a longer distance. In that case, it was necessary to newly install an optical transmission device.

Further, when the one-wavelength optical transmission system which does not perform wavelength multiplexing, which is currently laid in various places, is to be used as it is for the wavelength-multiplexed optical transmission system, in the conventional system, the input interface of the wavelength-multiplexed optical transmitter 1A and Since the output interface of the wavelength division multiplexing optical receiver 1B is an electric signal, there is a problem that the optical signal transmitted from the existing one wavelength optical transmission system cannot be directly input to the conventional system for wavelength division multiplexing.

In the conventional wavelength division multiplexing optical transmission system shown in FIG. 19, the interface between the optical transmitters 18A and 18B and the wavelength division multiplexer 1P and the interface between the wavelength demultiplexer 1Q and the optical receivers 19A and 19B are provided. It is an optical signal and can be transmitted over a long distance between the respective devices. However, it is necessary to control the wavelength of the optical signal input to the wavelength division multiplexer 1P by the optical transmitters 18A and 18B.

Further, the major features of the wavelength division multiplexing optical transmission system are that the transmission capacity can be flexibly changed by changing the number of multiplexed wavelengths according to the demand of the network, and that the destination can be specified for each wavelength. As shown in Figure 1,
In the conventional wavelength division multiplexing optical transmission system shown in FIG. 9, the user has to newly install a transmission / reception device of a specific wavelength in the system according to the increase in the number of multiplexing, and there is a problem that the versatility is lacking.

[0014] The present invention has been made to solve the above problems, and purpose to obtain an optical transmission equipment which can flexibly respond to the conventional optical transmission system.

[0015]

Means for Solving the Problems An optical transmission device in the first invention has multiplexing a plurality of optical signals, an optical transmission apparatus for transmitting a multiplexed optical signal, an optical receiver for receiving multi-optical signal An optical transmission device for performing long-distance optical transmission of 10 km or more, wherein the optical transmission device comprises a plurality of optical cables.
Optical signal of the transmitting side for converting the optical signal of the arbitrary wavelength into separate electric signals, and a plurality of electric signals converted by the transmitting side optical / electrical converting means for long-distance optical transmission.
In the above, the transmitting side electrical / optical converting means for converting into a plurality of optical signals having wavelengths suitable for multiplexing, and the plurality of optical signals converted by the transmitting side electrical / optical converting means are multiplexed and output as a multiplexed optical signal. And the above-mentioned multiplexing means
A transmission side amplifier for amplifying the multiplexed optical signal et, with shielding electromagnetic waves, the transmitting-side optical / electrical conversion means, and a transmission casing for storing the transmission-side electrical / optical conversion hand stage, The optical receiving device amplifies the received multiplexed optical signal
A receiving-side amplifying means, separating means for separating a plurality of optical signals constituting the multiplexed optical signal multiplexed optical signal from the receiving side amplifying means, each of different plural optical signals separated by said separating means Receiving-side optical / electrical converting means for converting into electric signals, and receiving-side electric / optical converting means for converting the respective electric signals converted by the receiving-side optical / electrical converting means into optical signals of a plurality of arbitrary wavelengths. and together when shielding electromagnetic waves, Ru der having a receiving casing for storing the upper Symbol recipient optical / electrical conversion means and the receiving side electric / optical conversion means.

The optical transmission apparatus of the second invention, multiplexing a plurality of optical signals, an optical transmission apparatus for transmitting a multiplexed optical signal, an optical receiver for receiving multiplexed optical signal transmitted from the optical transmission device An optical transmission device having, wherein the optical transmission device includes a transmission side wavelength conversion means for wavelength converting an optical signal of a plurality of arbitrary wavelengths into an optical signal of a wavelength suitable for the multiplexing, and the transmission side wavelength conversion means. Multiplexing means for multiplexing a plurality of wavelength-converted optical signals and outputting as a multiplexed optical signal, and an optical signal of an arbitrary wavelength input to the transmission side wavelength converting means are input, and the wavelength of the optical signal of the arbitrary wavelength is input. And a control signal generating means for generating and outputting a control signal indicating the detection result by the wavelength detecting means, wherein the optical receiving device is transmitted from the optical transmitting device. The above multiple optical communication A plurality of separating means for separating the optical signal, the receiving side wavelength converter for wavelength-converting the plurality of optical signals separated by said separating means into optical signals of a plurality of arbitrary wavelengths constituting the multiplexed optical signal, receiving on SL system patronized signals, and has a wavelength control means for controlling the reception side wavelength conversion means to wavelength conversion in accordance with the detection result by the wavelength detection means shown in the control signal . Here, the transmission side wavelength conversion means corresponds to the optical / electrical conversion units 8A and 8B and the electric / optical conversion units 3A and 3B in the embodiments described later. The reception side wavelength conversion means corresponds to the electric / optical conversion units 4A and 4B and the optical / electrical conversion units 9A and 9B in the embodiments described later. The control signal generation means is a control signal transmission unit 1 in the embodiments described later.
Equivalent to 61.

In the optical transmission device according to the third aspect of the invention, the wavelength detecting means has a grating whose reflection angle changes according to the wavelength, and the optical signal of an arbitrary wavelength input to the transmitting side wavelength converting means is described above. The wavelength is reflected by the grating and the wavelength of the optical signal of the arbitrary wavelength is detected according to the reflection angle.

In the optical transmission device according to the fourth aspect of the present invention, the wavelength detection means has a plurality of optical filter groups provided at predetermined wavelength intervals, and an optical signal of an arbitrary wavelength input to the transmission side wavelength conversion means. the input to the optical filter group, and detects the wavelength of the optical signal of the arbitrary wavelength depending on whether transmitted through the optical filter group.

The optical transmitting apparatus of the fifth invention, a transmitting side wavelength converter for wavelength-converting the optical signals of a plurality of arbitrary wavelengths in the optical signal of the wavelength suitable for the multi-duplex, wavelengths by the transmitting side wavelength converting means Multiplexing a plurality of converted optical signals, the multiplexing means for outputting as a multiplexed optical signal, the optical signal of an arbitrary wavelength input to the transmission side wavelength conversion means is input, the wavelength of the optical signal of the arbitrary wavelength wavelength detection means for detecting, on
Note that the above-mentioned wavelength detector is used on the receiving device side that receives the multiplexed optical signal.
And a control signal generating means for generating and outputting a control signal indicating the detection result by the wavelength detecting means so that the wavelength detected by the stage can be reproduced .

The optical receiving apparatus according a sixth aspect of the present invention, transmission instrumentation
Receiving a plurality of multiplexed optical signals formed of a light signal from 置側, separating means for separating to said plurality of optical signals, the upper
Receives a control signal that specifies the conversion wavelength from the transmitter side.
From the separating means according to the content of the control signal.
The wavelength control that controls the wavelength conversion of the above optical signals
Controlling means, and the plurality of the above separated by the above separating means.
The optical signal is controlled by the wavelength control means by the control signal.
And a receiving side wavelength conversion means for converting the wavelength to the wavelength designated by the above.

The optical transmission apparatus in the seventh aspect of the present invention, a plurality of
Optical transmitter that multiplexes optical signals and transmits as multiplexed optical signals
And an optical receiver for receiving multiplexed optical signals.
An optical transmission device for performing long-distance optical transmission of m or more,
The optical transmitter is an optical signal of arbitrary wavelength from multiple optical cables.
Transmitting side separating means for separating the signal into a plurality of systems, and the transmitting side
Input multiple optical signals from multiple systems separated by the separating means.
Of wavelengths suitable for the above multiplexing in long-distance optical transmission.
Transmission side wavelength conversion means for converting into a plurality of optical signals of a plurality of systems
And a plurality of systems converted by the transmission side wavelength conversion means
Multiple optical signals for each system are multiplexed for each system
Multiplexing means to output as optical signal and shield electromagnetic wave
Along with the transmission side housing for storing the transmission side wavelength conversion means
The optical receiving device has a body and
Receiving a signal, a plurality of constituting each issue multiple Mitsunobu
Receiving side separating means for separating into optical signals, and the receiving side separating hand
Multiple optical signals of multiple systems separated by stages for each system
A wavelength conversion means for converting into an optical signal of a plurality of arbitrary wavelengths,
There are multiple options for each system converted by the wavelength conversion means.
Input optical signal of desired wavelength and select optical signal to output to the outside
The optical switch means to
Having a receiving side housing for storing the receiving side wavelength conversion
Is.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1. The present embodiment relates to a wavelength division multiplexing optical transmitter capable of inputting an optical signal having an arbitrary wavelength corresponding to an input side and a wavelength division multiplexing optical receiving device capable of outputting an optical signal having an arbitrary wavelength corresponding to an output side. And will be described below with reference to FIG. FIG. 1 is a circuit configuration diagram of a wavelength division multiplexing optical transmitter and a wavelength division multiplexing optical receiver according to this embodiment.

In FIG. 1, reference numeral 1A is a wavelength division multiplexing optical transmitter that multiplexes and outputs an input optical signal, and 1B is a transmission line optical fiber 7A described later in the wavelength division multiplexing optical transmitter 1A.
It is a wavelength division multiplexing optical receiving device connected via. 2A,
2B is a separate transmission electric signal, 3A, 3B
Are electric / optical converters for converting the electric signals 2A and 2B into optical signals of wavelengths λ1 and λ2, respectively.

Reference numerals 4A and 4B denote optical / electrical converters for converting optical signals having wavelengths λ1 and λ2 into electrical signals 2A and 2B, respectively, and 5A and 5B are wavelengths from multiplexed optical signals transmitted by the transmission line optical fiber 7A. The optical filter extracts optical signals of λ1 and λ2. 6A is an optical coupler that combines optical signals of wavelengths λ1 and λ2, and 6B is a transmission line optical fiber 7A.
It is an optical coupler for demultiplexing the multiplexed optical signal transmitted via the optical coupler.

Reference numeral 7A is a transmission line optical fiber for transmitting the multiplexed optical signal multiplexed by the wavelength multiplexing optical transmitter 1A to the wavelength multiplexing optical transmitter 1B. Reference numerals 8A and 8B denote optical / electrical conversion units that convert an optical signal having an arbitrary wavelength input into electric signals 2A and 2B, and 9A and 9B denote optical / electrical conversion units 4A and 4B.
It is an electric / optical conversion unit that converts the electric signals 2A and 2B converted in B into optical signals of arbitrary wavelengths.

10A and 10B are optical / electrical conversion units 8A and 8
An optical signal of an arbitrary wavelength input to B is input to the wavelength division multiplexing optical transmitter 1A from an existing optical terminal station. 10C, 10D
Is an optical signal of an arbitrary wavelength output from the electrical / optical converters 9A and 9B, and is output from the wavelength division multiplexing optical receiver 1B to the existing optical terminal station.

The wavelength division multiplexing optical transmitter 1A is provided with electric / optical converters 3A, 3B, optical / electrical converters 8A, 8B and an optical coupler 6A. These circuits are casings for shielding electromagnetic waves. It is provided in the body. In addition, in the wavelength division multiplexing optical receiver 1B, an optical coupler 6B, optical filters 5A and 5A,
B, optical / electrical conversion units 4A, 4B and electric / optical conversion unit 9
Although A and 9B are provided, these circuits are provided in a housing that shields electromagnetic waves. In FIG. 1, the casings of the wavelength division multiplexing optical transmitter 1A and the wavelength division multiplexing optical receiver 1B are indicated by square lines.

Next, the operation of the wavelength division multiplexing optical transmitter 1A and the wavelength division multiplexing optical receiver 1B in this embodiment will be described. First, the operation of the wavelength division multiplexing optical transmitter 1A will be described. Optical signals 10A and 10B having arbitrary wavelengths are input to the wavelength division multiplexing optical transmitter 1A from an existing optical terminal station.
Optical signals 10A, 1 input to the wavelength division multiplexing optical transmitter 1A
0B is converted into electrical signals 2A and 2B by optical / electrical conversion units 8A and 8B, respectively, and then converted into electrical / optical conversion units 3A and 3B.
The optical coupler 6A converts the optical signals of wavelengths λ1 and λ2 at B.
Entered in. The optical signals converted by the electrical / optical converters 3A and 3B are optical signals having wavelengths λ1 and λ2, respectively, which are wavelengths suitable for wavelength multiplexing by the optical coupler 6A. Specifically, for example, the wavelength is such that both optical signals do not interfere with each other.

The output end of the optical coupler 6A is connected to the transmission line optical fiber 7A, and the optical coupler 6A intensity-combines the optical signals of λ1 and λ2 and outputs the multiplexed optical signal to the transmission line optical fiber 7A.

Next, the operation of the wavelength division multiplexing optical receiver 1B will be described. The multiplexed optical signal transmitted to the wavelength multiplexing optical receiving apparatus 1B via the transmission line optical fiber 7A is the optical coupler 6B.
Entered in. The optical coupler 6B intensity-divides the input multiplexed optical signal and outputs it to the optical filters 5A and 5B.

The optical filters 5A and 5B pass only the optical signals of wavelengths λ1 and λ2 of the multiplexed optical signals and output them to the optical / electrical converters 4A and 4B, respectively. The optical / electrical converters 4A and 4B convert the optical signals of the wavelengths λ1 and λ2 input from the optical filters 5A and 5B, respectively, into electrical signals 2A and 2B, and output them.

The electric / optical converters 9A and 9B are provided with electric signals 2A and 4A respectively inputted from the optical / electrical converters 4A and 4B.
2B is converted into optical signals 10C and 10D having arbitrary wavelengths and output. The optical signals 10C and 10D are optical signals of arbitrary wavelengths corresponding to the output-side optical terminal station. The optical signals 10C and 10D output from the wavelength division multiplexing optical receiver 1B are transmitted to the existing optical terminal station.

The effects of the wavelength division multiplexing optical transmitter 1A and the wavelength division multiplexing optical receiver 1B in this embodiment will be described. Wavelength multiplex optical transmitter 1 according to the first embodiment
A can handle any wavelength of the input optical signals 10A and 10B. Also, the optical signals 10C and 1C output from the wavelength division multiplexing optical receiver 1B
0D can also be an optical signal of an arbitrary wavelength. Therefore, the interface with the existing optical terminal becomes easy.

Further, when the number of wavelength division multiplexing increases with the demand change of transmission capacity, there is no need to newly install an optical transmitter / receiver of a specific wavelength as in the conventional system, which is a versatile system.

In the transmission path optical fiber 7A, the optical signal of wavelength λ1 and the optical signal of wavelength λ2 transmitted from the wavelength division multiplexing optical transmitter 1A to the wavelength division multiplexing optical receiver 1B propagate. Since the wavelengths are converted by the electric / optical converters 3A and 3B to have wavelengths suitable for multiplexing, mutual interference between the two optical signals does not occur, and good transmission quality can be obtained for each.

Further, in the wavelength division multiplexing optical transmitter 1A, in order to convert into an optical signal of a wavelength suitable for performing optical multiplexing, the optical signal is once converted into an electrical signal 2 by the optical / electrical conversion units 8A and 8B.
Although A and 2B are used, in general, electric signals are easily damaged by electromagnetic waves from the outside. In this embodiment,
Since the optical / electrical converters 8A and 8B and the electrical / optical converters 3A and 3B are provided in the housing that shields electromagnetic waves, the electric signals 2A and 2B can be protected from the electromagnetic waves. This also applies to the wavelength division multiplexing optical receiver 1B. Electrical signals 2A and 2B are input to the conventional wavelength division multiplexing optical transmitter 1A shown in FIG. 18 and the conventional optical transmitters 18A and 18B shown in FIG.
2B will be input from an external circuit through an electric wire. At the time of such input, the transmission performance may be deteriorated due to the electric signals 2A and 2B being damaged by electromagnetic waves and the like. Also from the above points, the wavelength division multiplexing optical transmitter 1A and the wavelength division multiplexing optical receiver 1B in this embodiment have advantageous effects compared with the conventional example.

In this embodiment, the number of transmission signals is 2
In the case where the number of signals is n (> 2), a similar system can be constructed by performing electro-optical conversion with different wavelengths λ1 to λn. Further, since the system can be constructed with one transmission line optical fiber regardless of the increase in the number of transmission signals, there is an advantage that the installation cost can be reduced.

The optical / electrical converters 8A and 8B and the electrical / optical converters 3A and 3B function to convert the input optical signals of arbitrary wavelengths into optical signals of wavelengths λ1 and λ2. . The optical / electrical converters 4A and 4B and the electrical / optical converters 9A and 9B function to convert the optical signals of wavelengths λ1 and λ2 into optical signals of arbitrary wavelengths. Therefore, these circuits can be configured by other circuits capable of wavelength conversion. However, the optical / electrical converter and the circuit using the electric / optical converter have an advantage that wavelength conversion can be realized by a simple circuit.

When performing long-distance optical transmission, it is necessary to sensitively perform optical output, wavelength control, etc., and the electrical / optical conversion units 3A, 3B for converting optical signals of wavelengths suitable for wavelength multiplexing. The wavelength division multiplexing optical transmitter 1A having the above becomes effective. The long-distance optical transmission referred to here means an optical transmission of several tens of kilometers or more.

Embodiment 2. This embodiment relates to a wavelength division multiplexing optical transmitter 1A and a wavelength division multiplexing optical receiver 1B provided with an optical fiber amplifier, which will be described below with reference to FIG. FIG. 2 is a circuit configuration diagram of the wavelength division multiplexing optical transmitter 1A and the wavelength division multiplexing optical receiver 1B in this embodiment.

In FIG. 2, 7B is a transmission line optical fiber connected to the transmission line optical fiber 7A via a relay optical fiber amplifier 12A described later. Reference numeral 11A is a transmission output increasing optical fiber amplifier incorporated in the wavelength division multiplexing optical transmitter 1A.
A is connected to the output side of the optical coupler 6A and to the input side of the transmission line optical fiber 7A.

Reference numeral 11B is a receiving sensitivity improving optical fiber amplifier incorporated in the wavelength division multiplexing optical receiver 1B, and the receiving sensitivity improving optical fiber amplifier 11B is connected to the output side of the transmission line optical fiber 7B. Reference numeral 12A is a relay optical fiber amplifier inserted between the transmission path optical fibers 7A and 7B. The other configuration is similar to that of the previous embodiment, and thus the description is omitted.

Next, the operations of the wavelength division multiplexing optical transmitter 1A and the wavelength division multiplexing optical receiver 1B in this embodiment will be described. The operations of the optical / electrical conversion units 8A and 8B, the electric / optical conversion units 3A and 3B, and the optical coupler 6A are the same as those in the above-described embodiment, and therefore description thereof will be omitted. The transmission output increasing optical fiber amplifier 11A increases the power of the multiplexed optical signal output from the optical coupler 6A to increase the power of the transmission path optical fiber 7.
Output to A.

The repeater optical fiber amplifier 12A increases the power of the attenuated multiplexed optical signal between the transmission line optical fiber 7A and the transmission line optical fiber 7B which are the relay points in the transmission line to increase the power of the transmission line optical fiber 7B. Output to.

Optical fiber amplifier 11B for improving receiving sensitivity
Is input to the optical coupler 6B by increasing the power of the multiplexed optical signal input from the transmission path optical fiber 7B to improve the receiving sensitivity. After the optical coupler 6B, the optical filters 5A, 5B,
Optical / electrical converters 4A and 4B, electrical / optical converters 9A and 9B
The operation of this circuit is the same as that of the first embodiment, and therefore its explanation is omitted.

The effects of the wavelength division multiplexing optical transmitter 1A and the wavelength division multiplexing optical receiver 1B in this embodiment will be described. In this embodiment, an optical fiber amplifier is inserted in the transmission line of the wavelength-multiplexed optical signal, and the multiplexed optical signal is collectively amplified by the inserted optical fiber amplifier, so that the transmission is performed regardless of the number of signals. The distance can be increased. In this embodiment, the case where one relay optical fiber amplifier 12A is used has been described, but it can be applied to the case where there are a plurality of optical fiber amplifiers, and further long distance transmission can be realized.

In this embodiment, the transmission output increasing optical fiber amplifier 11A is provided in the wavelength division multiplexing optical transmitter 1A, and the reception sensitivity improving optical fiber amplifier 11B is provided in the wavelength division multiplexing optical receiver 1B. An optical signal can be amplified even when connecting to an existing transmission line optical fiber.

Embodiment 3. This embodiment relates to a wavelength division multiplexing optical transmitter including a wavelength division multiplexing optical transmitter and a wavelength division multiplexing optical receiver, which will be described below with reference to FIG. FIG. 3 is a circuit configuration diagram of a wavelength division multiplexing optical transceiver according to this embodiment. In FIG. 3, 1A and 1H are wavelength division multiplexing optical transmitters, and 1B and 1I are wavelength division multiplexing optical receivers.

Reference numerals 1C and 1D denote wavelength-multiplexing optical transmitter / receivers, and the wavelength-multiplexing optical transmitter / receiver 1C denotes wavelength-multiplexing optical transmitter / receiver 1.
A wavelength division multiplexing optical receiver 1I, and a wavelength multiplexing optical transmitter / receiver 1D includes a wavelength multiplexing optical transmitter 1H and a wavelength multiplexing optical receiver 1B.

Reference numeral 7C is a transmission line optical fiber for connecting the optical coupler 6C in the wavelength division multiplexing optical transmitter 1H and the optical coupler 6D in the wavelength division multiplexing optical receiver 1I. The internal configurations of the wavelength division multiplexing optical transmitters 1A and 1H and the wavelength division multiplexing optical receivers 1B and 1I are the same as those in the first embodiment, and therefore their explanations are omitted.

The wavelength division multiplexing optical transmitter / receivers 1C and 1D in this embodiment are the wavelength division multiplexing optical transmitters 1A and 1H and the wavelength division multiplexing optical receivers 1B and 1I of the wavelength division multiplexing optical transmission system shown in Embodiment 1, respectively. Are configured as one set. Such a wavelength division multiplexing optical transmitter / receiver enables bidirectional transmission of wavelength division multiplexing transmission between two points.

The optical signals 10A and 10B of arbitrary wavelengths are transmitted through the wavelength multiplexing optical transmitter 1A, the transmission line optical fiber 7A and the wavelength multiplexing optical receiver 1B, and the optical signals 10C and 10B of arbitrary wavelengths are transmitted.
It is output as D. In addition, an optical signal 10E having an arbitrary wavelength,
10F is output as optical signals 10G and 10H of arbitrary wavelengths through the wavelength division multiplexing optical transmitter 1H, the transmission line optical fiber 7C, and the wavelength division multiplexing optical receiver 1I. The operations of the wavelength division multiplexing optical transmitters 1A and 1H and the wavelength division multiplexing optical receivers 1B and 1I are the same as those in the first embodiment, and therefore their explanations are omitted.

The effects of the wavelength division multiplexing optical transceivers 1C and 1D in this embodiment will be described. According to the wavelength division multiplexing optical transmitters / receivers 1C and 1D of this embodiment, since wavelength division multiplexing optical transmission can be performed by bidirectional transmission, a transmission system for exchanging information can be constructed.

Fourth Embodiment This embodiment relates to a wavelength division multiplexing optical transmitter and a wavelength division multiplexing optical receiver having dual circuits, which will be described below with reference to FIG. FIG. 4 is a circuit configuration diagram of the wavelength division multiplexing optical transmitter and the wavelength division multiplexing optical receiver in this embodiment. In FIG. 4, 1K is a wavelength division multiplexing optical transmitter, and 1L is a wavelength division multiplexing optical receiver connected to the wavelength division multiplexing optical transmitter 1K via transmission line optical fibers 7A and 7H.

Reference numerals 6G and 6H denote optical couplers for demultiplexing the optical signals 10A and 10B of arbitrary wavelengths, respectively, and are provided in the wavelength division multiplexing optical transmitter 1K. The optical coupler 6G outputs the demultiplexed optical signal 10A to the two optical / electrical conversion units 8A connected in parallel, and the optical coupler 6H outputs the demultiplexed optical signal 10B in two optical / electrical conversions. Output to the unit 8B.

Reference numeral 7H is a transmission line optical fiber, which connects the optical coupler 6A in the wavelength division multiplexing optical transmitter 1K and the optical coupler 6B in the wavelength division multiplexing optical receiver 1L. Reference numerals 14A and 14B denote optical switches that select optical signals of wavelengths λ1 and λ2 transmitted in two systems, respectively.

Since the other numbers are the same as those in the first embodiment, the description thereof will be omitted. However, the wavelength division multiplexing optical transmitter 1K
Include the optical / electrical converters 8A and 8B and the electrical / optical converter 3
Two A, 3B, and two optical couplers 6A are provided to form a duplex structure. Further, the wavelength division multiplexing optical receiver 1L includes an optical coupler 6B, optical filters 5A and 5B,
Optical / electrical converters 4A and 4B, electrical / optical converters 9A and 9B
Two are provided for each, and the structure is duplicated.

Next, the operations of the wavelength division multiplexing optical transmitter 1K and the wavelength division multiplexing optical receiver 1L in this embodiment will be described. The optical couplers 6G and 6H have input optical signals 10A and 1A, respectively.
0B is demultiplexed and output in parallel to the two optical / electrical conversion units 8A and 8B connected in parallel.

On the transmitting side, the signals divided into two systems by the optical couplers 6G and 6H are wavelength-multiplexed by the same method as in the first embodiment and output to the transmission line optical fibers 7A and 7H.

On the receiving side, the transmission path optical fibers 7A, 7H
A multiplexed optical signal received via the optical coupler 6B, optical filters 5A and 5B, optical / electrical converters 4A and 4B, and electrical / optical converters 9A and 9B are output as optical signals 10C and 10D. Switch 1 from the two electrical / optical conversion units 9A
An optical signal 10C is output to each of 4A, and an optical signal 10D is output to the switch 14B from the two electric / optical conversion units 9B.

The optical switch 14A selects and outputs one of the input two-wave optical signals 10C, and the optical switch 14B
Selects and outputs one of the input two-wave optical signals 10D. When an abnormality occurs in one of the paths, the optical switches 14A and 14B switch to the other redundant path and output an optical signal.

The effects of the wavelength division multiplexing optical transmitter 1K and the wavelength division multiplexing optical receiver 1L in this embodiment will be described. In this embodiment, since the configuration in the wavelength division multiplexing optical transmitter 1K, the configuration in the wavelength division multiplexing optical receiver 1L, and the transmission path optical fibers 7A and 7H have a duplex structure,
You can build a system with improved reliability and excellent maintenance and operability.

Embodiment 5 This embodiment relates to another example of the wavelength division multiplexing optical transmitter and the wavelength division multiplexing optical receiver in which the circuit is duplicated, and will be described below with reference to FIG. FIG. 5 is an internal configuration diagram of the wavelength division multiplexing optical transmitter and the wavelength division multiplexing optical receiver in this embodiment.

In FIG. 5, 1T is a wavelength division multiplexing optical transmitter, and 1W is a wavelength division multiplexing optical receiver connected to the wavelength division multiplexing optical transmitter 1T via transmission line optical fibers 7A and 7H. 6M is an optical coupler for combining the two optical signals converted by the two electric / optical converting sections 9A, 6N is an optical coupler for combining the two optical signals converted by the two electric / optical converting sections 9B, Reference numerals 14C and 14D are optical switches for switching the input optical signals 10A and 10B to either one of the two wavelength division multiplexing transmission devices. Since other numbers are the same as those in FIGS. 1 and 4, the description thereof will be omitted.

Next, the operations of the wavelength division multiplexing optical transmitter 1T and the wavelength division multiplexing optical receiver 1W in this embodiment will be described. First, the operation of the wavelength division multiplexing optical transmitter 1T will be described. The optical switch 14C outputs the input optical signal 10A to the optical / electrical converter 8A, which is one of the two optical / electrical converters 8A. Similarly, the optical switch 14D outputs the input input optical signal 10B to either one of the optical / electrical conversion units 8B. After that, the same operation as in the first embodiment is performed, and the wavelength-multiplexed multiplexed optical signal is output from either one of the two optical couplers 6A to the transmission path optical fiber 7A or the transmission path optical fiber 7H.

Next, the operation of the wavelength division multiplexing optical receiver 1W will be described. The wavelength division multiplexing optical receiver 1W receives the multiplexed optical signal via the transmission path optical fiber 7A or the transmission path optical fiber 7H. After that, the operations up to the electric / optical conversion units 9A and 9B operate in the same manner as in the first embodiment, and therefore the description thereof is omitted. Then, an optical signal 10C having an arbitrary wavelength is output to the optical coupler 6M from either of the two electric / optical conversion units 9A. Further, an optical signal 10D having an arbitrary wavelength is output to the optical coupler 6N from either of the two electric / optical conversion units 9B. Optical signals 10C and 10D are output from the optical couplers 6M and 6N, respectively. In this way, the transmission from the wavelength division multiplexing optical transmitter 1T to the wavelength division multiplexing optical receiver 1W is performed. However, when an abnormality occurs in the normally selected transmission system path, the optical switches 14C and 14D make the redundant system. Switch the route.

The effects of the wavelength division multiplexing optical transmitter 1T and the wavelength division multiplexing optical receiver 1W in this embodiment will be described. According to this embodiment, it is possible to construct a system with improved reliability and excellent maintenance and operability by adopting a dual structure for the transmission path.

Sixth Embodiment In this embodiment, the wavelength-division-multiplexing optical transmitter transmits an instruction to match the wavelength of the optical signal output from the wavelength-division-multiplexing optical receiver with the wavelength of the optical signal input to the wavelength-division-multiplexing optical transmitter. 6 will be described. FIG. 6 is a circuit configuration diagram of the wavelength division multiplexing optical transmitter and the wavelength division multiplexing optical receiver according to this embodiment.

In FIG. 6, 1M is a wavelength division multiplexing optical transmitter, and 1N is a wavelength division multiplexing optical receiver connected to the wavelength division multiplexing optical transmitter 1M via a transmission line optical fiber 7A.

3C is a wavelength detection / control signal transmitter 1 described later.
An electric / optical conversion unit connected to the output side of 6A and the input side of the optical coupler 6A, and 4C is a light connected to the output side of the optical filter 5C described later and the input side of the wavelength controller 17A described later. / It is an electrical conversion unit. 5C is an optical filter connected to the output side of the optical coupler 6B and the input side of the optical / electrical conversion unit 4C. 6G is an optical coupler connected to the optical / electrical conversion unit 8A and the input side of the optical switch 14E described later, and 6H is an optical coupler connected to the input side of the optical / electrical conversion unit 8B and the optical switch 14E described later. .

Reference numeral 14E is an optical switch connected to the output side of the optical couplers 6G and 6H and the input side of the wavelength detection / control signal transmitter described later. Reference numeral 16A denotes a wavelength detection / control signal transmitter connected to the output side of the optical switch 14E and the input side of the electrical / optical conversion unit 3C. The wavelength detection / control signal transmitter 16A includes the wavelength detection unit 160 and the control signal. Transmitter 161
Composed of and.

Reference numeral 17A is a wavelength controller connected to the output side of the optical / electrical converting section 4C and the input sides of the electric / optical converting sections 9A and 9B. Since other numbers are the same as those in FIG. 1, the description thereof will be omitted.

Next, the operation of the wavelength division multiplexing optical transmitter 1M and the wavelength division multiplexing optical receiver 1N in this embodiment will be described. First, the operation of the wavelength division multiplexing optical transmitter 1M will be described. Optical signals 10A and 10B of arbitrary wavelengths are input to the wavelength division multiplexing optical transmitter 1M. The optical coupler 6G demultiplexes the input optical signal 10A, and the optical / electrical converter 8A
To the optical switch 14E. The optical coupler 6H demultiplexes the input optical signal 10B and outputs the demultiplexed optical signal 10B to the optical / electrical converter 8B and the optical switch 14E.

Of the optical signals 10A and 10B demultiplexed by the optical couplers 6G and 6H, the optical signal output to the optical / electrical converters 8A and 8B is the wavelength in the same procedure as in the previous embodiment. It is multiplexed.

Of the optical signals 10A and 10B demultiplexed by the optical couplers 6G and 6H, the other optical signal is the optical switch 1
Input to 4E. The optical switch 14E selects one of the input optical signals 10A and 10B and outputs it to the wavelength detection / control signal transmitter 16A. The wavelength detection / control signal transmitter 16A detects the wavelength of the input optical signal and outputs an electrical control signal indicating the detected wavelength to the electrical / optical conversion unit 3C. This electrical control signal is an electrical signal that encodes the wavelength detected by the wavelength detector 160.

The electric / optical converter 3C converts the inputted electric control signal into an optical signal of wavelength λ3 and outputs it to the optical coupler 6A. The optical signal of wavelength λ3 converted by the electric / optical conversion unit 3C becomes the control optical signal. Optical coupler 6A
Performs wavelength multiplexing of the control optical signal of wavelength λ3 together with the optical signals of wavelengths λ1 and λ2, and transmits the multiplexed optical signal to the transmission path optical fiber 7A. The optical signals converted by the electrical / optical converters 3A, 3B, 3C have wavelengths λ1, λ2,
The optical signal is λ3, and this wavelength is suitable for wavelength multiplexing by the optical coupler 6A. Specifically, for example, the wavelength is such that both optical signals do not interfere with each other.

Next, the operation of the wavelength division multiplexing optical receiver 1N will be described. In the wavelength division multiplexing optical receiver 1N, the optical coupler 6
B receives the multiplexed optical signal received via the transmission line optical fiber 7A, and branches the received multiplexed optical signal into three and outputs it to the optical filters 5A, 5B, and 5C. Optical filter 5A,
5B and 5C are wavelengths λ1 and λ from the multiplexed optical signal, respectively.
The optical signals of 2 and λ3 are extracted. The optical signals having the wavelengths λ1 and λ2 are processed in the same procedure as in the above-mentioned embodiment.
The control optical signal of wavelength λ3 is input to the optical / electrical conversion unit 4C, and the optical / electrical conversion unit 4C converts the control optical signal of wavelength λ3 into an electric signal and outputs it to the wavelength controller 17A.

The wavelength controller 17A includes an optical / electrical conversion section 4C.
A wavelength division multiplexing optical transmitter 1M according to an electric signal output from
The control signal for recognizing the wavelength of the optical signal input to the optical multiplexer and transmitting the control signal to the wavelength-multiplexing optical transmitter 1M to convert it to the same wavelength as the optical signal input to the wavelength division multiplexing optical transmitter 1M is transmitted to the electrical / optical converters 9A and 9B.

The electric / optical converters 9A and 9B are the electric signals 2A and 2B converted by the optical / electrical converters 4A and 4B.
Based on the control signal input from the wavelength controller 17A, is converted into an optical signal having the same wavelength as the transmission-side input signal 10A or 10B and output.

The effects of the wavelength division multiplexing optical transmitter 1M and the wavelength division multiplexing optical receiver 1N in this embodiment will be described. According to this embodiment, since the input / output interface on the transmission / reception side of the device is an optical signal of the same wavelength, compatibility with the conventional optical transmission system is good, and a system with excellent expandability of the entire system including transmission / reception is constructed. it can. Therefore, when the wavelength division multiplexing optical transmitter 1M and the wavelength division multiplexing optical receiver 1N are newly introduced into the existing optical transmission system, the compatibility with the existing optical transmission system can be improved, and the interface mismatch may occur. Inconvenience can be prevented. It also leads to prevention of deterioration of the transmitted optical signal.

The switch 1 in this embodiment
4E selects one of the input optical signals 10A and 10B and outputs it to the wavelength detection / control signal transmitter 16A, but it outputs both optical signals by switching the switch. You can also In this case, the optical signals converted by the electric / optical converters 9A and 9B can be the optical signals having the same wavelengths as the transmission side input signals 10A and 10B.

Optical / electrical conversion section 8 in this embodiment
The A and 8B and the electric / optical converters 3A and 3B function so as to convert the inputted optical signal of an arbitrary wavelength into an optical signal of a wavelength suitable for multiplexing, and therefore, these can be considered as wavelength converting means. . In addition, the optical / electrical conversion units 4A and 4B and the electric / optical conversion units 9A and 9B according to this embodiment.
Can function as converting an optical signal having a wavelength suitable for multiplexing into an optical signal having an arbitrary wavelength, and thus can be considered as wavelength converting means.

Seventh Embodiment In this embodiment, the wavelength detector 160 in the sixth embodiment will be described in more detail. FIG. 7 shows the wavelength detection unit 1 provided in the wavelength detection / control signal transmitter 16A shown in FIG.
It is an internal block diagram of 60, and shows one structural example of the wavelength detection part 160. In the figure, 7I is an optical switch 1.
The optical switch 14E is an optical fiber connected to the output side of 4E and the input side of a wavelength detection unit 160A described later.
And outputs the optical signal output from the wavelength detection unit 160A described later. Reference numeral 160A is a wavelength detector, 20A is a light receiving element, and 21A is a grating that reflects the light output from the optical fiber 7I. The grating 21A reflects the irradiated light, and this reflection angle has an angle according to the wavelength of the irradiated light. 22A is a wavelength detector 160
It is a slit provided in A, and an opening is provided in the slit 22A.

Next, the operation of the wavelength detector 160A in this embodiment will be described. The optical signal output from the optical switch 14E is input to the wavelength detection unit 160A via the optical fiber 7I. The input optical signal is applied to the grating 21A and reflected by the grating 21A. Since the grating 21A reflects light at a reflection angle according to the wavelength of the emitted light, the opening of the slit 22A is installed at an appropriate position on the extension of the reflected light path, and only the optical signal of a specific wavelength passes through. To set in advance.

An optical signal of a specific wavelength that has passed through the slit is converted into an electric signal by the light receiving element 20A, and the control signal transmitter 1
It is output to 61. A large number of wavelength detection units 160A are installed at wavelength intervals with sufficient resolution, and control signal transmitter 161
Calculates the wavelength from the intensity distribution of the electric signal converted by the light receiving element 20A in the wavelength detector 160A, creates a wavelength control signal, and outputs it.

Eighth Embodiment In this embodiment, the wavelength detector 160 in the sixth embodiment will be described in more detail. FIG. 8 shows a wavelength detection unit 1 provided in the wavelength detection / control signal transmitter 16A shown in FIG.
It is an internal block diagram of 60, and shows the other structural example of the wavelength detection part 160.

In the figure, 5H is a narrow band optical filter group in which a large number of narrow band optical filters are installed at wavelength intervals having sufficient resolution. 160B is a wavelength detection unit in this embodiment. The wavelength detection unit 160B in this embodiment includes a narrow band optical filter 5H and a light receiving element 20A.
Composed of and. Since other numbers are the same as those in FIG. 7,
The description is omitted.

Next, the wavelength detector 1 in this embodiment
The operation of 60B will be described. The optical signal output from the optical switch 14E is input to the wavelength detection unit 160B via the optical fiber 7I. The input optical signal is applied to the narrow band optical filter group 5H. The optical signal of the specific wavelength that has passed through the narrow band optical filter group 5H is converted into an electric signal by the light receiving element 20A, and the intensity distribution of the wavelength is output to the control signal transmitter 161. The control signal transmitter 161 calculates a wavelength from the input wavelength intensity distribution, creates a wavelength control signal indicating the wavelength obtained from the calculation result, and outputs the wavelength control signal.

Ninth Embodiment In this embodiment, the wavelength detector 160 in the sixth embodiment will be described in more detail. FIG. 9 shows the wavelength detection unit 1 provided in the wavelength detection / control signal transmitter 16A shown in FIG.
It is an internal block diagram of 60, and shows the other structural example of the wavelength detection part 160. In the figure, 160C is a wavelength detector in this embodiment, and 23A is a spectrum analyzer provided in the wavelength detector 160C.

Next, the operation of the wavelength detector 160C in this embodiment will be described. The signal output from the optical switch 14E is input to the wavelength detection unit 160C via the optical fiber 7I. The input optical signal is input to the spectrum analyzer 23A. The spectrum analyzer 23A converts the wavelength intensity of the optical signal input by the optical fiber 7I into an electric signal, and the control signal transmitting unit 161.
Output to. The control signal transmitter 161 calculates the wavelength of the optical signal input by the optical fiber 7I from the intensity distribution output from the spectrum analyzer 23A, and creates and outputs a wavelength control signal.

Embodiment 10. In this embodiment, the wavelength detector 160 in the sixth embodiment will be described in more detail. FIG. 10 is an internal configuration diagram of the wavelength detection unit 160 provided in the wavelength detection / control signal transmitter 16A in FIG. 6, and shows another configuration example of the wavelength detection unit 160. In FIG. 10, 160D is the wavelength detection unit in this embodiment, and the wavelength detection unit 160D is composed of the circuit shown below.

6J is an optical coupler connected to the transmission side optical fiber 7I and the output side of a local light source 24A described later, 24A is a local light source which emits light of different wavelengths periodically, and 20A is an output side of the optical coupler 6J. Is a light receiving element connected to. 25A
Is a low-pass filter connected to the output side of the light-receiving element 20A, 26A is a wavelength intensity distribution data calculation unit connected to the output side of the low-pass filter 25A, and 26B is an output side of the wavelength intensity distribution data calculation unit 26A and the local light source 24A. Is a local oscillation wavelength control unit connected to the input side of. The wavelength intensity distribution data calculation unit 26A outputs to the local oscillation wavelength control unit 26B a signal for setting the wavelength variation period of the optical signal emitted by the local oscillation light source 24A and the wavelength variation width.

Next, the wavelength detector 1 in this embodiment
The operation of 60D will be described. The optical signal output from the optical switch 14E is input to the wavelength detection unit 160D via the optical fiber 7I. The input optical signal is intensity-combined with the local light from the local light source 24A by the optical coupler 6J. The wavelength of the local oscillation light output from the local oscillation light source 24A is configured to periodically monotonically increase with time according to the control signal input from the local oscillation light wavelength control unit 26B.

Then, when the wavelength of the optical signal input via the optical fiber 7I and the wavelength of the local oscillation light match,
Homodyne detection is performed by the light receiving element 20A and the low pass filter 25A. Since the homodyne-detected optical signal has a periodic intensity distribution on the time axis, this distribution is converted into wavelength intensity distribution data by the wavelength intensity distribution data calculation unit 26A and output to the control signal transmitter 161. The control signal transmitter 161 calculates the wavelength from this intensity distribution, creates a wavelength control signal, and outputs it.

Incidentally, the light receiving element 2 in this embodiment
The 0A and the low-pass filter 25A function to perform homodyne detection of the optical signal, and these circuits can be regarded as detection means. It is also possible to configure by other circuits that can detect an optical signal.

Eleventh Embodiment This embodiment relates to a wavelength division multiplexing optical repeater installed between transmission line optical fibers for transmitting wavelength-multiplexed optical signals and capable of switching an output route of optical signals. explain.

FIG. 11 is an internal block diagram of the wavelength division multiplexing optical repeater in this embodiment. In FIG. 11, 1
E is a wavelength division multiplexing optical repeater installed between the transmission line optical fiber 7D for transmitting the wavelength-multiplexed optical signal and the transmission line optical fiber 7E. The wavelength division multiplexing optical repeater 1E in this embodiment is composed of the following circuits.

Reference numeral 8E is an optical / electrical conversion unit for converting an optical signal of an arbitrary wavelength input from the outside into the wavelength division multiplexing optical repeater 1E into an electric signal, and 9E is an electric switch 13A described later.
The electrical / optical conversion unit converts the electrical signal output from the optical signal into an optical signal of an arbitrary wavelength and outputs the optical signal.

13A selects the electric signal to be output to the electric / optical conversion unit 9E and outputs the electric signal to the electric / optical conversion unit 9E to the electric signal output from the optical / electrical conversion unit 8E in the empty signal transmission path. An electrical switch that inserts a signal, 15
A and 15B are wavelength-multiplexed optical signals transmitted through the transmission path optical fibers 7D and 7E. Since other numbers are the same as those in FIG. 1, the description thereof will be omitted.

Next, the operation of the wavelength division multiplexing optical repeater 1E in this embodiment will be described. Wavelength λ1 input to the wavelength division multiplexing optical repeater 1E from the transmission line optical fiber 7D
The wavelength-multiplexed optical signal 15A including the optical signals of λ2 and λ2 is intensity-distributed by the optical coupler 6B, only the optical signals of wavelengths λ1 and λ2 are extracted by the optical filters 5A and 5B, respectively, and the optical / electrical conversion units 4A and 4B. It is converted to electricity.

The two electric signals electrically converted by the optical / electrical converters 4A and 4B are input to the electric switch 13A. In the electric switch 13A, the optical / electrical conversion unit 4A,
One of the two electric signals input from 4B is selected and output to the electric / optical conversion unit 9E. The electric / optical conversion unit 9E converts the electric signal input from the electric switch 13A into an optical signal having an arbitrary wavelength and outputs the optical signal from the wavelength division multiplexing optical repeater 1E. The optical signal output from the electrical / optical conversion unit 9E is transmitted to the base station or general user in the relay section.

Further, an optical signal of an arbitrary wavelength is newly input to the optical / electrical converter 8E from the outside of the wavelength division multiplexing optical repeater 1E. The optical / electrical conversion unit 8E electrically converts the input optical signal of an arbitrary wavelength, and the electrical signal that has been electrically converted is input to the electrical switch 13A. The electric switch 13A is
The electrical signal input from the optical / electrical conversion unit 8E is emptied because one of the two electrical signals electrically converted by the optical / electrical conversion units 4A and 4B is output to the electrical / optical conversion unit 9E. Insert it in the transmission line.

The two electric signals output from the electric switch 13A are respectively converted into λ1 and λ1 by the electro-optical conversion units 3A and 3B.
It is converted into an optical signal of λ2, intensity-combined by the optical coupler 6A, and output to the transmission line optical fiber 7E as a new wavelength-multiplexed optical signal 15B. The optical signals converted by the electrical / optical converters 3A and 3B are optical signals having wavelengths λ1 and λ2, respectively, which are wavelengths suitable for wavelength multiplexing by the optical coupler 6A. Specifically, for example, the wavelength is such that both optical signals do not interfere with each other.

Next, the mode of switching by the switch 13A of the wavelength division multiplexing optical repeater 1E will be described with reference to Table 1.
Table 1 shows the output destinations of the electrical signals output from the optical / electrical conversion units 4A, 4B, 8E.

[0105]

[Table 1]

From Table 1, it can be seen that there are three modes of switching by the switch 13A, I to III.

The effects of the wavelength division multiplexing optical repeater 1E in this embodiment will be described. The wavelength division multiplexing optical repeater 1E in this embodiment can flexibly respond to a sudden communication request in the relay section of the transmission path, and can be applied not only as the backbone transmission but also as an access system. Specifically, when it becomes necessary to install a new communication base station in the repeater section, laying a new transmission line optical fiber requires cost and installation time. By using it, an optical signal can be easily supplied to a new base station. Further, by enabling signal input / output within the relay section, it becomes possible to construct a system in which general users around the relay point can exchange signals.

Further, in this embodiment, since the optical signal is once converted into the electric signal, the switching can be performed by the commonly used electric signal switch 13A. Further, the switching control can be easily performed by using the switch 13A for electric signals. Further, in this embodiment, since the switch 13A is used, it is effective in that the multiplexed optical signal can be output switchably.

Twelfth Embodiment This embodiment relates to a wavelength division multiplexing optical repeater installed between transmission line optical fibers for transmitting wavelength-multiplexed optical signals and capable of switching the output path of optical signals. explain. FIG. 12 is an internal block diagram of the wavelength division multiplexing optical repeater in this embodiment.

In FIG. 12, 1R is a wavelength division multiplexing optical repeater installed between the transmission line optical fiber 7D for transmitting the wavelength-multiplexed optical signal and the transmission line optical fiber 7E.
The wavelength division multiplexing optical repeater 1R in this embodiment is composed of the following circuits.

In FIG. 12, 10A1 is an output optical signal of wavelength λ1 output from the wavelength division multiplexing optical repeater 1R.
C1 is an input optical signal of wavelength λ1 newly input from the outside of the wavelength division multiplexing optical repeater 1R. 27A is an optical filter having a characteristic of transmitting only an optical signal having a specific wavelength λ1 and reflecting an optical signal having another wavelength in one direction, and 28A and 28D emit the optical signal to the optical filter 27A. Output ports 28B and 28C are input ports into which the optical signal transmitted through the optical filter 27A is incident. Since other numbers are the same as those in FIG. 11, the description thereof will be omitted.

Next, the operation of the wavelength division multiplexing optical repeater 1R in this embodiment will be described. Wavelength λ1 input to the wavelength division multiplexing optical repeater 1R from the transmission line optical fiber 7D
The wavelength-multiplexed optical signal 15A including the optical signals of λ2 and λ2 is output to the optical filter 27A from the output port 28D.

Of the optical signals emitted to the optical filter 27A, only the optical signal having the wavelength λ1 passes through the optical filter 27A and the optical signals having other wavelengths are reflected in one direction. The optical signal of wavelength λ1 that has passed through the optical filter 27A is input to the incident port 28B and is extracted from the wavelength multiplexing optical repeater 1R as the optical signal 10A1 of wavelength λ1. The optical signal output from the incident port 28B is transmitted to the base station or general user in the relay section.

Further, another optical signal 10C1 of wavelength λ1 is newly input from the outside of the wavelength division multiplexing optical repeater 1R, and the optical signal 10C1 is transmitted through the emission port 28A to the optical filter 27.
Emitted to A. The optical filter 27A has a wavelength λ1.
The optical signal 10C1 of wavelength λ1 that has passed through the optical filter 27A is input to the incident port 28C in order to transmit the optical signal of.

On the other hand, the optical signal of wavelength λ2 emitted from the emission port 28D and reflected by the optical filter 27A has a wavelength of λ1.
And is input to the incident port 28C. The incident port 28C is connected to the transmission line optical fiber 7E, and the optical signal incident on the incident port 28C is used as a new wavelength division multiplexed optical signal 15B.
It is output to E.

With the above operation, the optical filter 27
By A, the optical signal of the inner wavelength λ1 of the plurality of optical signals forming the wavelength multiplexed optical signal 15A is separated and the output optical signal 10A is obtained.
Input optical signal 10C output as 1 and newly input
1 is multiplexed and output to the transmission path optical fiber 7E.

The effect of the wavelength division multiplexing optical repeater 1R in this embodiment will be described. Originally, the repeater is configured to directly amplify and output a signal that has entered for the purpose of extending the transmission distance. However, the wavelength division multiplexing optical repeater 1R in this embodiment is capable of inputting and outputting a specific wavelength that is a repeater point. It can be carried out. That is, it is possible to flexibly respond to a sudden communication request in the relay section of the transmission path, and it can be applied not only as a backbone transmission but also as an access system. Further, since the present system relays the optical signal as it is without converting the optical signal into an electrical signal, the device configuration is simple, and low cost and high reliability can be realized. The optical filter 27A in this embodiment separates the optical signal of wavelength λ1 and
It can be regarded as a demultiplexing unit that multiplexes the newly input input optical signal 10C1. Therefore, the optical filter 27A can be replaced with another circuit capable of demultiplexing.

Thirteenth Embodiment This embodiment relates to a wavelength division multiplexing optical repeater installed between transmission line optical fibers for transmitting wavelength-multiplexed optical signals and capable of switching output routes of a plurality of optical signals transmitted by the transmission line optical fibers. This will be described below with reference to FIG. FIG. 13 is an internal configuration diagram of the wavelength division multiplexing optical repeater according to this embodiment.

In FIG. 13, 1U is a wavelength division multiplexing optical repeater installed between a transmission line optical fiber 7D for transmitting wavelength-division multiplexed optical signals and a transmission line optical fiber 7E.
The wavelength division multiplexing optical repeater 1U in this embodiment is composed of the following circuits.

In FIG. 13, 6K and 6L are optical couplers,
10B1 is an output optical signal of wavelength λ2 output from the wavelength division multiplexing optical repeater 1U, and 10D1 is a wavelength division multiplexing optical repeater 1U.
Input optical signal of wavelength λ2 newly input from outside
5C and 15D are wavelength-multiplexed optical signals transmitted in the relay section.

27B is an optical filter having a characteristic of reflecting only an optical signal of a specific wavelength λ1 and transmitting an optical signal of another wavelength, and 27C reflects only an optical signal of a specific wavelength λ2, It is an optical filter having a characteristic that an optical signal having a wavelength of is transmitted. 28E to 28H are ports for inputting / outputting optical signals for bidirectional transmission to / from the optical filter 27B or 27C, and 29A is a wavelength-multiplexing optical repeater 1
An optical circulator for inputting / outputting from U and a mirror 30A for reflecting an optical signal of wavelength λ3 transmitted through the optical filter 27C. Since the other numbers are the same as those in FIG. 12, the description thereof will be omitted.

Next, the operation of the wavelength division multiplexing optical repeater 1U in this embodiment will be described. The wavelength λ input to the wavelength division multiplexing optical repeater 1U from the transmission line optical fiber 7D.
WDM optical signal 15 including optical signals of 1, λ2 and λ3
C is input to the optical circulator 29A.

Port 2 via the optical circulator 29A
The wavelength-multiplexed optical signal 15C input to 8H is input to the optical filter 27B. Since the optical filter 27B has a characteristic of reflecting only the optical signal of the wavelength λ1 and transmitting the other wavelengths, the optical signals of the wavelengths λ2 and λ3 of the wavelength division multiplexed optical signal 15C pass through the optical filter 27B.

The optical signal having the inner wavelength λ1 of the wavelength-division multiplexed optical signal 15C is reflected by the optical filter 27B, input to the port 28F and then input to the optical coupler 6K. The optical signal 10A1 of the wavelength λ1 input to the optical coupler 6K is 1 of the optical coupler 6K.
The signal is output from the end to the outside of the wavelength division multiplexing optical repeater 1U.

Further, another optical signal 10C1 of the wavelength λ1 is newly input from the outside of the wavelength division multiplexing optical repeater 1U, passes through the optical coupler 6K, and is output from the port 28F to the optical filter 27B.
Is emitted to. The optical signal 10C1 is newly input from a base station in the relay section or a general user. The optical filter 27B has a characteristic of reflecting only the optical signal of wavelength λ1 and therefore reflects the optical signal of wavelength λ1. Optical filter 27
The optical signal 10C1 of the wavelength λ1 that reflects B is input to the port 28
Input to H.

On the other hand, the optical signals of the wavelengths λ2 and λ3 emitted from the port 28H and transmitted through the optical filter 27B are incident on the optical filter 27C via the port 28E. Since the optical filter 27C has a characteristic of reflecting only the wavelength λ2 and transmitting the other wavelengths, it reflects the optical signal of the wavelength λ2 and transmits the optical signal of the wavelength λ3.

The optical signal of wavelength λ2 reflected by the optical filter 27C is the same as the optical signal of wavelength λ1 in the ports 28G,
The output optical signal 10B1 is output from the wavelength division multiplexing optical repeater 1U via the optical coupler 6L. Further, another optical signal 10D1 having a wavelength λ2 is newly input to the optical coupler 6L from the outside of the wavelength division multiplexing optical repeater 1U, and the port 28G and the optical filter 27C are used to perform the same operation as the input optical signal having the wavelength λ1. 28E. The optical signal 10D1 is newly input from a base station or a general user in the relay section.

Further, the optical signal of wavelength λ3 that has passed through the optical filter 27C is totally reflected by the mirror 30A and is input again to the optical filter 27C. The optical signal of wavelength λ3 that has passed through the optical filter 27C is combined with the optical signal of wavelength λ2, passes through the port 28E, passes through the optical filter 27B, and is combined with the optical signal of wavelength λ1 to form the wavelength multiplexed optical signal 15D. It is input to the port 28H. The wavelength-division multiplexed optical signal 15D input from the port 28H to the optical circulator 29A passes through the optical circulator 29A and the transmission path optical fiber 7E.
Is output to.

With this operation, the optical signal of wavelength λ3 among the wavelength multiplexed optical signals 15C including the optical signals of wavelengths λ1, λ2 and λ3 transmitted by the transmission path optical fiber 7D is transmitted by the transmission path optical fiber 7E. To be done. Among the wavelength-multiplexed optical signals 15C, the optical signals of wavelengths λ1 and λ2 have their transmission paths switched and are output from the optical coupler 6K or 6L. The optical signal output from the optical coupler 6K or 6L is output to the base station or general user in the relay section.

On the other hand, the input optical signals 10C1 and 10D1 newly input to the optical coupler 6K or 6L have the wavelength λ3.
Is transmitted as a wavelength-division multiplexed optical signal 15D together with the optical signal No.

The wavelength division multiplexing optical repeater 1U in this embodiment has the following effects in addition to the same effects as those of the above-mentioned twelfth embodiment. The effect will be described below. The wavelength division multiplexing optical repeater 1U according to the present embodiment can deal with the input of two input optical signals and the output of two output optical signals, and can withstand more complicated transmission path switching requests. That is, it is possible to flexibly respond to a sudden communication request in the relay section of the transmission path, and it can be applied not only as a backbone transmission but also as an access system. Further, although the optical signal propagates bidirectionally in the transmission path between the optical circulator 29A and the optical couplers 6K and 6L and the mirror 30A, since the traveling directions are different, mutual interference does not occur and good transmission quality can be obtained.

Fourteenth Embodiment This embodiment relates to a wavelength division multiplexing optical repeater that is installed between transmission line optical fibers that transmit wavelength-multiplexed optical signals and that can switch the output route of the optical signals transmitted by the transmission line optical fibers. Yes, the following Figure 14
It will be described based on. FIG. 14 is an internal configuration diagram of the wavelength division multiplexing optical repeater according to this embodiment.

In FIG. 14, reference numeral 1S denotes a wavelength division multiplexing optical repeater installed between the transmission line optical fiber 7D for transmitting wavelength-division multiplexed optical signals and the transmission line optical fiber 7E.
In FIG. 14, 10I is an output optical signal of an arbitrary wavelength output from the wavelength division multiplexing optical repeater 1S, and 10J is an input optical signal of an arbitrary wavelength newly input from outside the wavelength division multiplexing optical repeater 1S. The other numbers are the same as those in FIG. 11 and FIG. 12, and therefore their explanations are omitted.

Next, the operation of the wavelength division multiplexing optical repeater 1S in this embodiment will be described. The wavelength division multiplexed optical signal 15A including the optical signals of wavelengths λ1 and λ2 input to the wavelength division multiplexed optical repeater 1S from the transmission line optical fiber 7D is transmitted to the port 2
It is incident on the optical filter 27A via 8D. Of the wavelength division multiplexed optical signal 15A, the optical signal of wavelength λ1 is the optical filter 2
7A, and the optical / electrical conversion unit 4 through the port 28B.
Input to A.

The optical signal input to the optical / electrical converting section 4A is once converted into an electrical signal by the optical / electrical converting section 4A, and further converted into an optical signal by the electrical / optical converting section 9E. The optical signal converted by the electric / optical conversion unit 9E becomes an optical signal having a wavelength that matches the output side. Electrical/
The optical signal output from the optical conversion unit 9E is output to the base station or general user in the relay section.

On the other hand, an input optical signal 10J of an arbitrary wavelength newly input from the outside of the wavelength division multiplexing optical repeater 1S, for example, a base station in the repeater section or a general user, is temporarily converted into an electrical signal by the optical / electrical converting section 8E. And is further converted into an optical signal by the electric / optical signal converter 3A. The optical signal converted by the electric / optical signal converter 3A becomes a signal of wavelength λ1. This wavelength is suitable for wavelength division multiplexing. Specifically, for example, the wavelength is such that a plurality of optical signals to be multiplexed do not interfere with each other.

The optical signal converted by the electric / optical signal converting section 3A is incident on the optical filter 27A via the port 28A. Since the optical filter 27A has a characteristic of transmitting the optical signal of the wavelength λ1, the optical signal converted by the electric / optical signal conversion unit 3A is output to the transmission line optical fiber 7E via the port 28C.

The effect of the wavelength division multiplexing optical repeater 1S in this embodiment will be described. The wavelength division multiplexing optical repeater 1S in this embodiment can flexibly respond to a sudden communication request in the relay section of the transmission path, and can be applied not only to the backbone transmission but also to the access system. Also,
The wavelength division multiplexing optical repeater 1S according to this embodiment can input an input optical signal 10J having an arbitrary wavelength and output optical signal 10 having an arbitrary wavelength that matches the wavelength on the output side.
I can be output. That is, since the wavelength division multiplexing optical repeater 1S in this embodiment has an input / output interface for an optical signal of an arbitrary wavelength, it can flexibly correspond to the existing optical transmission system.

The optical / electrical conversion unit 8E and the electric / optical conversion unit 3A function to convert the input optical signal of an arbitrary wavelength into an optical signal of wavelength λ1. Further, the optical / electrical conversion unit 4A and the electric / optical conversion unit 9E function to perform wavelength conversion of the optical signal having the wavelength λ1 into the optical signal having the arbitrary wavelength.
Therefore, these circuits can be configured by other circuits capable of wavelength conversion. However, light /
A circuit using the electric conversion unit and the electric / optical conversion unit has an advantage that wavelength conversion can be realized by a simple circuit.

Fifteenth Embodiment This embodiment relates to a wavelength division multiplexing optical repeater that is installed between transmission line optical fibers that transmit wavelength-multiplexed optical signals and that can switch the output route of the optical signals transmitted by the transmission line optical fibers. Yes, below Figure 15
It will be described based on. FIG. 15 is an internal block diagram of the wavelength division multiplexing optical repeater in this embodiment.

In FIG. 15, 1V is a wavelength division multiplexing optical repeater installed between a transmission line optical fiber 7D for transmitting wavelength-multiplexed optical signals and a transmission line optical fiber 7E.
The wavelength division multiplexing optical repeater 1V in this embodiment is configured by adding the following circuit in addition to the wavelength division multiplexing optical repeater described in the thirteenth embodiment.

In FIG. 15, 8E and 8F are input optical signals 10J input from the outside of the wavelength division multiplexing optical repeater 1V,
An optical / electrical conversion unit for converting 10 L into an electric signal,
E and 9F are electric / optical converters for converting electric signals into optical signals of arbitrary wavelengths. 10K is an output optical signal of an arbitrary wavelength output from the wavelength division multiplexing optical repeater 1V to the outside, and 10L is an input optical signal of an arbitrary wavelength newly added from the outside of the wavelength division multiplexing optical repeater 1V. Other numbers are shown in FIGS.
The description is omitted because it is the same as FIG. 13.

Next, the operation of the wavelength division multiplexing optical repeater 1V in this embodiment will be described. The wavelength λ input to the wavelength division multiplexing optical repeater 1V from the transmission line optical fiber 7D.
WDM optical signal 15 including optical signals of 1, λ2 and λ3
C is input to the optical circulator 29A. The optical signal having the inner wavelength λ1 of the input wavelength-multiplexed optical signal 15C is input to the optical coupler 6K via the same route as in the thirteenth embodiment. In addition, the internal wavelength λ of the input wavelength-multiplexed optical signal 15C
The optical signal No. 2 is input to the optical coupler 6L via the same route as in the thirteenth embodiment.

The optical signal of wavelength λ1 input to the optical coupler 6K is once converted into an electric signal by the optical / electrical converting section 4A, and further converted into an optical signal by the electric / optical signal converting section 9E. Then, the optical signal converted by the electrical / optical conversion unit 9E is output as an output optical signal 10I to the outside of the wavelength division multiplexing optical repeater 1V. This output optical signal 10I is
It can be an optical signal of an arbitrary wavelength according to the output side.

The optical signal of wavelength λ2 input to the optical coupler 6L is output to the outside of the wavelength division multiplexing optical repeater 1V as an output optical signal 10K via the optical / electrical conversion section 4B and the electrical / optical conversion section 9F. The output optical signal 10K can be an optical signal having an arbitrary wavelength according to the output side.

An input optical signal 10J having an arbitrary wavelength is newly input from the outside of the wavelength division multiplexing optical repeater 1V, is once converted into an electric signal by the optical / electrical converting section 8E, and is further converted into a wavelength by the electric / optical converting section 3A. It is converted into an optical signal of λ1. This wavelength λ1 is a wavelength suitable for wavelength multiplexing. Specifically, for example, the wavelength is such that a plurality of optical signals to be multiplexed do not interfere with each other. The optical signal of wavelength λ1 converted by the electrical / optical conversion unit 3A passes through the optical coupler 6K and is output to the transmission line optical fiber 7E through the same procedure as in the thirteenth embodiment.

Further, an input optical signal 10L having an arbitrary wavelength is newly input from the outside of the wavelength division multiplexing optical repeater 1V, and is input to the optical coupler 6L via the optical / electrical converting section 8E and the electrical / optical converting section 3B. It The optical signal converted by the electrical / optical conversion unit 3B becomes an optical signal of wavelength λ2, and this optical signal has a wavelength suitable for wavelength multiplexing. In particular,
For example, the wavelength is such that a plurality of optical signals to be multiplexed do not interfere with each other. The optical signal input to the optical coupler 6L is then output to the transmission line optical fiber 7E through the same procedure as in the thirteenth embodiment.

Further, the optical signal of wavelength λ3 that has passed through the optical filter 27C is totally reflected by the mirror 30A and is input again to the optical filter 27C. The optical signal of wavelength λ3 that has passed through the optical filter 27C is combined with the optical signal of wavelength λ2, passes through the port 28E, passes through the optical filter 27B, and is combined with the optical signal of wavelength λ1 to form the wavelength multiplexed optical signal 15B. It is input to the port 28H. The wavelength-division multiplexed optical signal 15D input from the port 28H to the optical circulator 29A passes through the optical circulator 29A and the transmission path optical fiber 7E.
Is output to.

With this operation, the optical signal of wavelength λ3 among the wavelength multiplexed optical signals 15C including the optical signals of wavelengths λ1, λ2 and λ3 transmitted by the transmission path optical fiber 7D is transmitted by the transmission path optical fiber 7E. To be done. Among the wavelength-multiplexed optical signals 15C, the optical signals of the wavelengths λ1 and λ2 have their transmission paths switched and the electrical / optical conversion unit 9E or 9F.
Is output from.

On the other hand, the optical signal input to the optical / electrical converting section 8E or 8F is transmitted by the transmission line optical fiber 7E as the wavelength multiplexed optical signal 15D together with the optical signal of the wavelength λ3.

Effects of the wavelength division multiplexing optical repeater 1V in this embodiment will be described. The wavelength division multiplexing optical repeater 1V in this embodiment can flexibly respond to a sudden communication request in the repeater section of the transmission line, and can be applied not only to the backbone transmission but also to the access system.

Further, the wavelength division multiplexing optical repeater 1V in this embodiment is configured so that the input optical signals 10J and 1
In addition to being able to input 0L, it is possible to output the output optical signals 10I and 10K having arbitrary wavelengths that match the wavelength on the output side. That is, since the wavelength division multiplexing optical repeater 1V in this embodiment has an input / output interface for an optical signal of an arbitrary wavelength, it can flexibly correspond to the existing optical transmission system.

The optical / electrical converters 8E and 8F and the electric / electrical converters
The optical converters 3A and 3B function to convert the input optical signal of an arbitrary wavelength into optical signals of wavelengths λ1 and λ2. Further, the optical / electrical converters 4A and 4B and the electrical / optical converters 9E and 9F function to convert the optical signals of the wavelengths λ1 and λ2 into optical signals of arbitrary wavelengths. Therefore, these circuits can be configured by other circuits capable of wavelength conversion. However, the optical / electrical converter and the circuit using the electric / optical converter have an advantage that wavelength conversion can be realized by a simple circuit.

Sixteenth Embodiment This embodiment is a wavelength division multiplexer that is installed at a relay point of a transmission line optical fiber that transmits a wavelength-multiplexed optical signal, and further wavelength-multiplexes a new optical signal generated at the relay point and transmits it by the transmission line optical fiber. The present invention relates to an optical repeater and will be described below with reference to FIG. 16
It is an internal block diagram of the wavelength division multiplexing optical repeater in this Embodiment.

In FIG. 16, 1G is a wavelength division multiplexing optical repeater installed between the transmission line optical fiber 7D for transmitting the wavelength-multiplexed optical signal and the transmission line optical fiber 7E.
The wavelength division multiplexing optical repeater 1G in this embodiment is composed of the following circuits.

In FIG. 16, 2C is an input optical signal 10 of an arbitrary wavelength input from the outside of the wavelength division multiplexing optical repeater 1G.
J is an electrical signal obtained by electrical conversion, 4C is an optical / electrical conversion unit for electrically converting an input optical signal 10J having an arbitrary wavelength, 6C is an optical coupler, 7D and 7E are transmission line optical fibers, 9G and 9
H and 9I indicate electric signals having wavelengths λ11, λ21, λ, respectively.
31 is an electric / optical conversion unit for converting into 31 optical signals. Since other numbers are the same as those in FIG. 1, the description thereof will be omitted.

Next, the operation of the wavelength division multiplexing optical repeater 1G in this embodiment will be described. Wavelength λ1 input to the wavelength division multiplexing optical repeater 1G from the transmission line optical fiber 7D
The wavelength-multiplexed optical signal 15A including the optical signals of λ2 and λ2 is intensity-distributed by the optical coupler 6B, and only the optical signals of wavelengths λ1 and λ2 are extracted by the optical filters 5A and 5B.

The optical signals of the wavelengths λ1 and λ2 extracted by the optical filters 5A and 5B are respectively converted into the optical / electrical conversion section 4.
After being inputted to A and 4B and once converted into electric signals 2A and 2B, the wavelengths λ1 are converted by the electric / optical converters 9G and 9H.
It is converted into an optical signal of 1, λ21 and input to the optical coupler 6C.

Further, the input optical signal 10J of a new arbitrary wavelength input from the outside of the wavelength division multiplexing optical repeater 1G is
The electric signal is converted into an electric signal 2C by the electric conversion unit 4C, then converted into an optical signal having a wavelength λ31 by the electric / optical conversion unit 9I and input to the optical coupler 6C. Electric / optical converter 9
The optical signals after being converted by G, 9H, and 9I are optical signals having wavelengths λ11, λ21, and λ31, and this wavelength is determined in advance so as to be a wavelength suitable for multiplexing by the optical coupler 6C. . Specifically, the wavelength is such that a plurality of optical signals do not interfere with each other when multiplexed. In the optical coupler 6C, the wavelengths λ11, λ21, λ
31 optical signals are wavelength-multiplexed, and wavelength-multiplexed optical signals 15E
Is output to the transmission path optical fiber 7E.

The wavelength division multiplexing optical repeater 1G in this embodiment is a system that flexibly responds to a new communication request in the relay section of the transmission path and also flexibly responds to an access system and the like. The number of multiplexed wavelengths is increased by newly adding the input optical signal 10J as an optical signal to be wavelength-multiplexed. The wavelength interval of the optical signal to be wavelength-multiplexed is changed according to such a change in the number of multiplexed wavelengths. By changing to a wavelength suitable for wavelength multiplexing by the optical conversion units 9G to 9I, it is possible to construct a system in which the influence of inter-channel interference is reduced.

The optical / electrical converters 4A, 4B, 4C and the electrical / optical converters 9G, 9H, 9I convert optical signals of wavelengths λ1, λ2 and arbitrary wavelengths into optical signals of λ11, λ21, λ31. Is working. Therefore, these circuits can be configured by other circuits capable of wavelength conversion. However, the optical / electrical converter and the circuit using the electric / optical converter have an advantage that wavelength conversion can be realized by a simple circuit.

Embodiment 17. FIG. This embodiment is installed at a relay point of a transmission line optical fiber that transmits a wavelength-multiplexed optical signal, extracts part of the optical signal from the wavelength-multiplexed optical signal, and wavelength-multiplexes the remaining optical signal. The present invention relates to a wavelength division multiplexing optical repeater for transmitting by a transmission line optical fiber, which will be described below with reference to FIG. FIG. 17 is an internal configuration diagram of the wavelength division multiplexing optical repeater according to this embodiment.

In FIG. 17, reference numeral 1J is a wavelength division multiplexing optical repeater installed between a transmission line optical fiber 7D for transmitting wavelength-division multiplexed optical signals and a transmission line optical fiber 7E.
The wavelength division multiplexing optical repeater 1J in this embodiment is composed of the following circuits.

In FIG. 17, reference numeral 4C designates an optical / electrical converter 5E, 5F, which converts an optical signal of wavelength λ33 into an electrical signal.
Reference numeral 5G is an optical filter for extracting optical signals of wavelengths λ13, λ23, λ33, 6D is an optical coupler for synthesizing the optical signals, and 9J is an electric / optical conversion unit for converting electric signals into optical signals. Since the other numbers are the same as those in FIGS. 1 and 16, the description thereof will be omitted.

Next, the operation of the wavelength division multiplexing optical repeater 1J in this embodiment will be described. The wavelength λ1 input to the wavelength division multiplexing optical repeater 1J from the transmission line optical fiber 7D.
The wavelength-multiplexed optical signal 15F including the optical signals of 3, λ23 and λ33 is intensity-distributed by the optical coupler 6D, and the optical filter 5
Wavelengths λ13, λ23, λ33 for E, 5F, and 5G, respectively.
Only the optical signal of is extracted.

The wavelengths λ13, λ23, λ33 extracted by the optical filters 5E, 5F, 5G are converted into electric signals 2A, 2B, 2C by the optical / electrical converters 4A, 4B, 4C, respectively. The signal 2C is converted into an optical signal 10I having an arbitrary wavelength by the electrical / optical conversion unit 9J, and the wavelength division multiplexing optical repeater 1
It is output to the outside of J. On the other hand, the signals 2A and 2B are converted into optical signals of wavelengths λ1 and λ2 by the electric / optical converters 9A and 9B, respectively, and the converted optical signals of wavelengths λ1 and λ2 are wavelength-multiplexed by the optical coupler 6A. The multiplexed optical signal 15B is output to the transmission line optical fiber 7E.

Effects of the wavelength division multiplexing optical repeater 1J in this embodiment will be described. The wavelength division multiplexing optical repeater in this embodiment is a system that flexibly responds to a new communication request in the relay section of the transmission path, and also flexibly responds to an access system and the like. Also, by changing the setting of the wavelength interval of each electro-optical conversion unit for each wavelength-multiplexed optical repeater according to the change in the number of multiplexed wavelengths, it is possible to construct a system in which the influence of inter-channel interference is reduced.

The optical / electrical converters 4A, 4B, 4C and the electrical / optical converters 9A, 9B, 9J have wavelengths λ13, λ2.
It functions to perform wavelength conversion of optical signals of 2 and λ32 into optical signals of wavelengths λ1, λ2 and arbitrary wavelengths. Therefore, these circuits can be configured by other circuits capable of wavelength conversion. However, the optical / electrical converter and the circuit using the electric / optical converter have an advantage that wavelength conversion can be realized by a simple circuit.

[0169]

[Effect of the Invention] The optical transmission device according to the invention, ten k with an optical signal of multiple multiplexing, an optical transmission apparatus for transmitting a multiplexed optical signal, an optical receiver for receiving multi-optical signal
An optical transmission device for performing long-distance optical transmission of m or more, wherein the optical transmission device includes transmission-side optical / electrical conversion means for converting optical signals of arbitrary wavelengths from a plurality of optical cables into different electric signals. Transmitting side electrical / optical converting means for converting the plurality of electrical signals converted by the transmitting side optical / electrical converting means into a plurality of optical signals having wavelengths suitable for the multiplexing in long-distance optical transmission , and the transmitting side electrical / electrical converting means. / Multiplexing means for multiplexing a plurality of optical signals converted by the optical converting means and outputting the multiplexed optical signals, and a multiplexed optical signal from the multiplexing means
And transmitting-side amplifying means for amplifying, with shielding electromagnetic waves, and a transmission casing for storing the transmission side optical / electrical converting means, the transmission-side electrical / optical conversion hand stage, the light receiving device, Receiving side amplifying means for amplifying received multiple optical signal
If a separating means for separating the multiplexed optical signal from the receiving side amplifying means into a plurality of optical signals constituting the multiplexed optical signals, a plurality of optical signals separated by said separating means, respectively
A receiving-side optical / electrical conversion means for converting into another electrical signals, respectively converted by the reception side optical / electrical conversion means
A reception side electric / optical conversion means for converting the separate electrical signals into optical signals of a plurality of arbitrary wavelengths, to together when shielding electromagnetic waves, on <br/> Symbol recipient optical / electrical conversion means and the receiving side electric / Since it has a receiving side housing that stores the optical converting means, it is possible to apply an existing optical terminal station having an arbitrary wavelength to the input side of the optical transmitting device and the output side of the optical receiving device. You can flexibly adapt to the system. In addition, since each circuit is provided in the housing that shields electromagnetic waves, it is possible to prevent interference due to electromagnetic waves.

[Brief description of drawings]

FIG. 1 is a circuit configuration diagram of a wavelength division multiplexing optical transmitter and a wavelength division multiplexing optical receiver according to a first embodiment.

FIG. 2 is a circuit configuration diagram of a wavelength division multiplexing optical transmitter and a wavelength division multiplexing optical receiver according to a second embodiment.

FIG. 3 is a circuit configuration diagram of a wavelength division multiplexing optical transceiver according to a third embodiment.

FIG. 4 is a circuit configuration diagram of a wavelength division multiplexing optical transmitter and a wavelength division multiplexing optical receiver according to a fourth embodiment.

FIG. 5 is an internal configuration diagram of a wavelength division multiplexing optical transmitter and a wavelength division multiplexing optical receiver according to a fifth embodiment.

FIG. 6 is a circuit configuration diagram of a wavelength division multiplexing optical transmitter and a wavelength division multiplexing optical receiver according to a sixth embodiment.

FIG. 7 is an internal configuration diagram showing a configuration example of the wavelength detection unit 160.

FIG. 8 is an internal configuration diagram showing another configuration example of the wavelength detection unit 160.

FIG. 9 is an internal configuration diagram showing another configuration example of the wavelength detection unit 160.

FIG. 10 is an internal configuration diagram showing another configuration example of the wavelength detection unit 160.

FIG. 11 is an internal configuration diagram of a wavelength division multiplexing optical repeater according to an eleventh embodiment.

FIG. 12 is an internal configuration diagram of a wavelength division multiplexing optical repeater according to a twelfth embodiment.

FIG. 13 is an internal configuration diagram of a wavelength division multiplexing optical repeater according to a thirteenth embodiment.

FIG. 14 is an internal configuration diagram of a wavelength division multiplexing optical repeater according to a fourteenth embodiment.

FIG. 15 is an internal configuration diagram of a wavelength division multiplexing optical repeater according to a fifteenth embodiment.

FIG. 16 is an internal configuration diagram of a wavelength division multiplexing optical repeater according to a sixteenth embodiment.

FIG. 17 is an internal configuration diagram of a wavelength division multiplexing optical repeater according to a seventeenth embodiment.

FIG. 18 is a block diagram of a conventional wavelength division multiplexing optical transmission system.

FIG. 19 is a configuration diagram of another conventional wavelength division multiplexing optical transmission system.

[Explanation of symbols]

1A, 1H, 1K, 1M, 1T WDM optical transmitter,
1P wavelength multiplexer, 1B, 1I, 1L, 1N, 1W
WDM optical receiver, 1Q wavelength demultiplexer, 1C, 1D
WDM optical transceivers 1E, 1G, 1J, 1R, 1
S, 1U, 1V wavelength division multiplexing optical repeaters, 3A to 3D, 9A
~ 9J Electric / optical converter, 4A-4D, 8A-8F Optical / electric converter, 5A-5H, 27A-27C Optical filter, 6A-6N Optical coupler, 7A-7I Transmission line optical fiber, 11A For increasing transmission output Fiber amplifier, 11B
Fiber amplifier for improving reception sensitivity, 12A Optical fiber amplifier for relay, 13A Electric switch, 14A to 14E
Optical switch, 16A wavelength detection / control signal transmitter, 16
0A to 160D wavelength detector, 17A wavelength controller, 1
8A, 18B optical transmitter, 19A, 19B optical receiver, 20A light receiving element, 21A grating, 22
A slit, 23A Spectrum analyzer, 24A
Local light source, 25A low-pass filter, 26A wavelength intensity distribution data calculation unit, 26B Local light wavelength control unit, 2
8A to 28H port, 29A optical circulator, 30
A mirror.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI H04B 10/17 10/26 10/28 H04J 14/02 (56) Reference JP-A-8-251110 (JP, A) JP JP 62-209986 (JP, A) JP 62-48820 (JP, A) JP 4-252622 (JP, A) JP 55-140341 (JP, A) JP 55-105453 (JP , A) JP-A 8-316914 (JP, A) JP-A 61-19248 (JP, A) JP-A 60-165133 (JP, A) JP-A 62-59428 (JP, A) JP-A 8-19012 (JP, A) JP-A-7-107113 (JP, A) JP-A-2-224538 (JP, A) JP-A-5-130032 (JP, A) JP-A-3-53226 (JP, A) A) Japanese Unexamined Patent Publication No. 9-200808 (JP, A) Actual Development No. 6-54333 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) H04B 10/00 H 04J 14/00 INSPEC (DIALOG) JISST file (JOIS)

Claims (7)

(57) [Claims] 1. A multiplexing a plurality of optical signals, an optical transmission apparatus for transmitting a multiplexed optical signal, the multi Shigemitsu optical transmission apparatus which performs long-distance optical transmission of tens of km or more and a light receiver for receiving a signal The optical transmission device includes a transmission-side optical / electrical conversion means for converting optical signals of arbitrary wavelengths from a plurality of optical cables into different electric signals, and a plurality of optical signals converted by the transmission-side optical / electrical conversion means. and transmitting-side electrical / optical conversion means for converting the plurality of optical signals of wavelength suitable for the multiplexed electrical signals in long-distance optical transmission of a plurality of optical signal converted by the transmission-side electrical / optical conversion means Multiplexing means for multiplexing and outputting as multiplexed optical signals, and transmission side amplification for amplifying the multiplexed optical signals from the multiplexing means
Means, with shielding electromagnetic waves, the transmitting-side optical / electrical conversion means, and a transmission casing for storing the transmission-side electrical / optical conversion hand stage, the light receiving device, multiplexed optical signal received Receive to amplify
A side amplifying means, separating means for separating a plurality of optical signals constituting the multiplexed optical signal multiplexed optical signal from the receiving side amplifying means, it a plurality of optical signals separated by said separating means
A receiving-side optical / electrical conversion means for converting to another electric signal, which was converted by the reception side optical / electrical conversion means
Are different and the receiving side electric / optical conversion means for converting the electrical signal into an optical signal of a plurality of arbitrary wavelengths, to together when shielding electromagnetic waves, upper Symbol recipient optical / electrical conversion means and the receiving side electric / optical conversion means An optical transmission device having a receiving side housing for storing the. 2. A multiplexing a plurality of optical signals, an optical transmission device comprising a light transmitter for transmitting a multiplexed optical signal, an optical receiver for receiving multi-optical signal, the optical transmission apparatus, a plurality , A wavelength conversion means on the transmission side for converting an optical signal of an arbitrary wavelength into an optical signal of a wavelength suitable for the multiplexing, and a plurality of optical signals wavelength-converted by the wavelength conversion means on the transmission side are multiplexed to obtain a multiplexed optical signal. And a wavelength detecting means for detecting the wavelength of the optical signal of the arbitrary wavelength by inputting the optical signal of the arbitrary wavelength input to the transmitting side wavelength converting means, and the detection result by the wavelength detecting means. And a control signal generation means for generating and outputting a control signal indicating the optical signal, wherein the optical receiving device is a plurality of optical signals forming the multiplexed optical signal, the multiplexed optical signal transmitted from the optical transmitting device. Minutes to separate into signals And means, receiving-side wavelength converting means a plurality of optical signals demultiplexed wavelength into an optical signal of an arbitrary wavelength of the multiple <br/> number by said separating means, receiving the upper SL system patronized signal, the control And a wavelength control means for controlling the receiving side wavelength conversion means so as to perform wavelength conversion according to the wavelength detection result by the wavelength conversion means indicated by the signal for use in the optical transmission apparatus. 3. The wavelength detecting means has a grating whose reflection angle changes depending on the wavelength, reflects an optical signal of an arbitrary wavelength input to the transmitting side wavelength converting means to the grating, and reflects the reflection angle. 3. The optical transmission device according to claim 2, wherein the wavelength of the optical signal of the arbitrary wavelength is detected in accordance with the above. 4. The wavelength detecting means has a predetermined wavelength interval.
Having a plurality of optical filter groups provided, the optical signal of an arbitrary wavelength input to the transmission side wavelength conversion means is input to the optical filter group , and the optical wavelength of the arbitrary wavelength is changed depending on whether or not the optical signal passes through the optical filter group . The optical transmission device according to claim 2, wherein the wavelength of the optical signal is detected. 5. A transmitting side wavelength converter for wavelength-converting the optical signals of a plurality of arbitrary wavelengths in the optical signal of the wavelength suitable for multi-duplex, a plurality of optical signals whose wavelength is converted by the sender-side wavelength converter Multiplexing means for multiplexing and outputting as a multiplexed optical signal; wavelength detecting means for inputting an optical signal of an arbitrary wavelength input to the transmission side wavelength converting means and detecting the wavelength of the optical signal of the arbitrary wavelength ; The above wavelength detection on the receiving device side that receives multiple optical signals
An optical transmitter, comprising: a control signal generating means for generating and outputting a control signal indicating the detection result by the wavelength detecting means so that the wavelength detected by the means can be reproduced . 6. Demultiplexing means for receiving a multiplexed optical signal composed of a plurality of optical signals from the transmitter side and separating the optical signals into the plurality of optical signals, and controlling means for designating a conversion wavelength from the transmitter side. Signal
Depending on the content of the control signal received, the separation means
The wavelength to control the wavelength conversion of the above optical signals
The control means and the plurality of optical signals separated by the separating means are
Designation of the control signal by the control of the wavelength control means
An optical receiving device comprising: a receiving side wavelength converting means for converting a wavelength into a wavelength . 7. Multiple optical signals are multiplexed and
And an optical receiver for receiving multiplexed optical signals.
Optical transmission for long-distance optical transmission of 10 km or more
A sending device, The above-mentioned optical transmitter is provided with an arbitrary wavelength from a plurality of optical cables.
Transmitting side separating means for separating the optical signal into a plurality of systems, A plurality of multiple systems separated by the transmission side separation means
Inputs an optical signal and is suitable for the above multiplexing in long-distance optical transmission.
Side waves to be converted into multiple optical signals of multiple wavelengths
Length conversion means, A plurality of systems converted by the transmission side wavelength conversion means
Multiple optical signals are multiplexed for each system,
Signal output as a signal and shielding electromagnetic waves
At the same time, a transmission side housing that stores the transmission side wavelength conversion means and
Have The optical receiving device receives the multiplexed optical signals of the plurality of systems.
Into multiple optical signals that make up each multiplexed optical signal.
Receiving side separating means to separate, A plurality of multiple systems separated by the receiving side separation means
Optical signals of multiple wavelengths for each system
Wavelength conversion means, There are multiple options for each system converted by the wavelength conversion means.
Input optical signal of desired wavelength and select optical signal to output to the outside
Optical switch means for Shields electromagnetic waves and stores the above wavelength conversion on the receiving side
Optical transmission device having a receiving side housing
Place