JPH11268698A - Optical signal transmission equipment for aircraft - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To connect devices mounted on an aircraft with an optical fiber, it is possible to connect many terminals with expandability close to a linear coupler connection. SOLUTION: A data bus interface 30 is attached to each device and includes a coupler 32 and an optical amplifier 33. The optical amplifier 33 converts an optical signal into an electric signal, and after amplifying the electric signal, supplies operation power for converting the output to an optical signal from a power supply in the device-side circuit 40. The coupler 32 mixes an optical signal supplied from the main bus optical fiber 35 via the input side connector 31 with an optical signal supplied from the device side circuit 40 via the EO transceiver 37, and a part of the optical signal is supplied to the OE transceiver 38. Branch to The OE transceiver 38 converts an optical signal into an electric signal and inputs the electric signal to the device-side circuit 40. The optical signal from the coupler 33 is amplified by an optical amplifier 33 and output from an output connector 34.
Is output to the optical fiber 36 for the main bus.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical signal transmission device for an aircraft for connecting various devices mounted on an aircraft with an optical fiber.

[0002]

2. Description of the Related Art In recent years, sensors and actuators are mounted on various parts of an airframe of an aircraft to perform sophisticated and complicated control. For example, as shown in FIG. 6, a plurality of devices 1 to 8 are mounted on each part of the body of the aircraft 10, and various controls are performed. In the aircraft 10, data transmission between the devices 1 to 8 is performed via optical fibers 11, 12, 13,... So as to be hardly affected by electric noise.

FIG. 7 shows a bus line type topology formed by linear couplers 21, 22, 23, 24,... As a form of an aircraft optical data bus. The optical fibers 11, 12, 13, 14,... Constitute a main bus line, and are linear couplers 21, 22, which are T couplers.
Data is transmitted and received from the devices 2, 23, 24 to the devices 1, 2, 3, 4,.

As a connection form between a plurality of devices, a linear coupler 2 is connected to a main bus line as shown in FIG.
In addition to the configuration of adding 1, 22, 23, 24, ...,
It is also common to use star couplers. Star
In topologies using couplers, multiple devices are equally connected to one star coupler.

[0005]

In the topology of the main bus line system as shown in FIG.
By adding additional linear couplers to the line, it is possible to add more equipment and expandability. On the other hand, in the star coupler system, in order to expand the system such that the number of connected devices is increased, it is necessary to replace the coupler itself and reconnect the entire system. At this time, in some cases, it may be necessary to readjust the signal reception level or the like in all the connected devices.

On the other hand, a main unit as shown in FIG.
In the bus line method, the number of devices can be increased simply by connecting a linear coupler additionally. Therefore, the bus line method is superior to the star coupler method in terms of expandability. However, the intensity of the optical signal passing through the main bus line is attenuated each time the optical signal passes through the linear coupler, and it is expected that the signal will be extremely weak for the terminal device. For this reason,
The number of connected terminals is limited, and high-performance transceivers with a wide dynamic range are required for transmission and reception, so that the advantage of the main bus line system, which is scalable, cannot be exhibited. I will. If optical amplification is performed at the linear couplers 21, 22, 23, and 24, the problem of optical signal attenuation at the linear couplers 21, 22, 23, and 24 is eliminated. However, it is necessary to supply a power for optical amplification, and if the optical amplifier breaks down, the reliability decreases. That is, performing optical amplification in the linear couplers 21, 22, 23, and 24 means that the linear couplers 21, 22, 23, and 24 are electrically / electronically converted, and signal transmission is performed using an optical fiber. The advantage of performing is lost.

An object of the present invention is to provide an aircraft optical signal transmission apparatus for realizing an optical data bus connection mode which has expandability close to that of a linear coupler connection and can connect many terminals. That is.

[0008]

SUMMARY OF THE INVENTION The present invention relates to an aircraft optical signal transmission device for connecting equipment mounted on an aircraft by an optical fiber so that an optical signal can be transmitted. Input side connection means, and an optical signal input to the input side connection means is guided, and the electric signal from the device is converted into an optical signal and mixed, and a part of the optical signal is branched and converted into an electric signal. Means for inputting to the device by means of the mixing and branching means, optical amplification means for amplifying the optical signal from the mixing and splitting means using the electric power supplied from the equipment, and an optical fiber connected to the output side of the optical amplification means and connectable to the optical fiber An optical signal transmission device for an aircraft, comprising:

According to the present invention, an optical signal input from an optical fiber connectable to the input side connecting means is guided to the optical amplifying means via the mixing / branching means, and the output of the optical amplifying means is transmitted from the output side connecting means to the optical amplifying means. Can output to fiber. The mixing / branching means converts an electric signal from the device into an optical signal, mixes the signal with an optical signal input from an optical fiber, splits a part of the optical signal, converts the signal into an electric signal, and inputs the signal to the device. The optical signal output to the optical fiber connected to the output side connection means is amplified by the optical signal amplification means, and the power required for the amplification is supplied from the device. If an optical fiber is connected to the input side connection means and the output side connection means, and the optical fiber connection between the output side connection means on the upstream side and the input side connection means on the downstream side is sequentially repeated with respect to the transmission of the optical signal, linear It has the same expandability as that of coupler connection, and can be amplified by an optical amplifier so that the optical signal is less attenuated and transmitted sequentially.

In the present invention, a branching means is provided between the mixing / branching means and the optical amplifying means for branching an optical signal from the mixing / branching means, and an optical amplifying means is provided for the optical signal branched by the branching means. A delay unit that provides a delay equivalent to that of the optical amplifier, and an optical signal provided by the delay unit, which is provided between the optical amplifying unit and the output-side connecting unit, is mixed with an optical signal output from the optical amplifying unit and output. Mixing means for outputting to the side connection means.

According to the present invention, a part of the optical signal input from the mixing / branching unit to the optical amplifying unit is branched by the branching unit, given a delay equivalent to that of the optical amplifying unit, and connected to the output of the optical branching unit. They are mixed by mixing means. Even when the supply of power to the optical amplifying unit is stopped due to a failure of the device or the like, the optical signal can be transmitted through the delay unit. Since it is considered extremely unlikely that a plurality of devices fail at the same time, an optical signal is amplified by another optical signal transmission device for an aircraft, and the effect of the device failure can be compensated. When the device is operating normally, the optical amplifier is operated with the power supplied from the device, and the optical signal from the delay unit is mixed with the mixing unit,
Since a delay equivalent to that of the optical amplifying means is given by the delay means, the waveform of the signal does not change during mixing, and highly reliable transmission of an optical signal can be performed.

Further, according to the present invention, the optical signal branched from the mixing / branching unit is compared with the optical signal output from the optical amplifying unit, and the presence or absence of a failure of the optical amplifying unit is detected based on the comparison result. It is characterized by comprising a failure detecting means.

According to the present invention, the optical amplification means breaks down,
If the light mixed by the mixing means is distorted,
Since a difference occurs between the optical signal branched from the mixing / branching unit and the optical signal output from the optical amplifying unit, the difference can be detected as a failure based on the comparison result of the failure detecting unit. When a failure is detected, the influence of the failure can be eliminated by stopping the power supply to the optical amplification means.

[0014]

FIG. 1 shows a schematic configuration of a data bus interface 30 which is an aircraft optical signal transmission apparatus according to an embodiment of the present invention. The data bus interface 30 includes an input connector 31 as input connection means, a coupler 32 as mixing / branching means, an optical amplifier 33 as optical amplification means, and an output connector 34 as output connection means. . In the input side connector 31,
An optical fiber 35 for the main bus to which an optical signal from the upstream side is transmitted can be connected. An optical fiber 36 for a main bus that transmits an optical signal to the downstream side can be connected to the output side connector 34. An optical signal from an EO transceiver 37 that converts an electric signal into an optical signal can be mixed in the coupler 32. From the coupler 32, an optical signal to be input to an OE transceiver 38 that converts the optical signal into an electric signal can be branched. In the data bus interface 30, transmission of an optical signal from the input connector 31 to the input of the coupler 32, transmission of an optical signal from the output of the coupler 32 to the input of the optical amplifier 33, and transmission from the optical amplifier 33 to the output An optical fiber 39 is used for transmitting an optical signal to the connector 34. The output of the electric signal input from the EO transceiver 37 and the input of the electric signal output from the OE transceiver 38 are performed to the device-side circuit 40. The power supply for operation to the optical amplifier 33 is also supplied from the device side circuit 40.

In the optical amplifier 33, a light receiving element such as a photodiode or a phototransistor converts an optical signal input through the optical fiber 39 into an electric signal, and amplifies the electric signal through an electric amplifier circuit. Converts an electrical signal into an optical signal. A power supply from the device-side circuit 40 is used in the conversion and amplification processes. The EO transceiver 37 and the OE transceiver 38 also use the power supplied from the device-side circuit 40.

FIG. 2 shows an optical data bus connection configuration in which a plurality of devices 41 to 44 are connected in an optical bus system using the data bus interface 30 shown in FIG. Optical fibers 51, 52, 53,
54 and 55 are connected. Since the data bus interface 30 includes the optical amplifier 33, the optical signal is not attenuated even if the equipment is added. Therefore, many devices can be connected as terminals, and the system can be easily expanded.

FIG. 3 shows a schematic configuration of the coupler 32 shown in FIG. In the coupler 32, an optical fiber 39 for connection is used.
The fusion part 32 to which a part of the other optical fiber 32a is fused
b, the optical signal input to the optical fiber 32a and the optical signal passing through the optical fiber 39 are mixed at the fusion portion 32b, and a part of the optical signal passing through the optical fiber 39 is transmitted to the optical fiber 32a. Branch. The optical amplifier 33 shown in FIG. 1 performs amplification so as to compensate for the attenuation due to the branch of the optical signal at the coupler 32.

FIG. 4 shows a schematic configuration of a data bus interface 60 according to another embodiment of the present invention.
In the present embodiment, portions corresponding to the embodiment shown in FIG. 1 are denoted by the same reference numerals, and redundant description will be omitted. The data bus interface 60 of the present embodiment includes a first coupler 61, a second coupler 62, and a third coupler 63. The first coupler 61 is a coupler 3 of FIG.
Basically, the optical signal is mixed with the optical signal from the EO transceiver 37 and the optical signal input from the input connector 31, and a part of the optical signal is input to the device-side circuit 40 via the OE transceiver 38. Second coupler 6 serving as a branching means
2 branches into two systems of the optical signal from the first coupler 61. The third coupler 63, which is a mixing means, mixes two systems of optical signals. One of the two optical signals is amplified by the optical amplifier 33. The optical signals of the other systems of the two branched systems proceed as they are and consume time in the delay fiber 64. The delay fiber 64 is an optical fiber having a length necessary to simulate a time delay at the time of optical amplification in the optical amplifier 33. For this reason, the optical signal that has passed through the delay fiber 64 has the same time delay as the optical signal amplified by the optical amplifier 33, so that the waveform as a signal does not change when the optical signal is mixed by the third coupler 63 and merged. Can be

In this embodiment, the optical amplifier 33 and the delay fiber 6 are provided between the second coupler 62 and the third coupler 63.
4 is provided, and even if the optical amplifier 33 is not supplied with power due to a failure of the device side circuit 40 or the like, an optical signal of a certain intensity is transmitted to the next data bus interface via the system on the side of the delay fiber 64. 60 can be supplied. Since the devices mounted on the aircraft are configured to be highly reliable, it is extremely unlikely that two or more adjacent devices will fail simultaneously. By designing the output level and the light receiving sensitivity of the optical signal so that a few data bus interfaces 60 can be connected via the system on the side of the delay fiber 64, the system on the side of the optical amplifier 33 is Even if it does not function, the signal transmitted to the main bus of the optical data bus can be transmitted downstream by transmitting the optical signal through the system on the side of the delay fiber 64.

FIG. 5 shows a configuration of a data bus interface 70 according to still another embodiment of the present invention. In the present embodiment, portions corresponding to the embodiment of FIG. 1 or FIG. 4 are denoted by the same reference numerals, and redundant description will be omitted. This embodiment is different from the embodiment shown in FIG.
It has a configuration in which a transceiver 71 and a failure detection circuit 72 are added. The OE transceiver 71 converts a part of the optical signal output from the optical amplifier 33 into an electric signal. The failure detection circuit 72 compares the output from the OE transceiver 38, which converts the optical signal branched from the first coupler 61 into an electric signal, with the output from the OE transceiver 71, and detects a failure of the optical amplifier 33. The comparison in the failure detection circuit 72 is performed in consideration of the delay of the optical signal by the optical amplifier 33.

For example, when an optical signal is mixed from the device side circuit 40 to the first coupler 61 via the EO transceiver 37, a part of the mixed optical signal is input to the OE transceiver 38 by looping back. Converted to electrical signals. The optical signal mixed by the first coupler 61 is branched by the second coupler 62, amplified by the optical amplifier 33, and a part of the output is converted into an electric signal by the OE transceiver 71 and input to the failure detection circuit 72. Is done. If the protocol of the entire system is determined so that the optical signal transmitted through the optical fibers 35 and 36 for the main bus can be output only from the device-side circuit 40 having the right to use the bus, the data bus interface is established. When the device-side circuit 40 to which the device 70 is connected has the right to use the main bus, an optical signal for detecting the failure of the optical amplifier 33 by the failure detection circuit 72 is derived from the device-side circuit 40 and The signal comparison is performed in consideration of the time delay of the optical amplifier 33, and the failure of the optical amplifier 33 can be detected when the output signal of the optical amplifier 33 changes. When a failure is detected, the power supply to the optical amplifier 33 is cut off to stop the function of the optical amplifier 33. After the failure, the main bus optical fibers 35, 3
6, the control device of the entire system collects and determines information from the device-side circuit 40, and based on command data from the control device, the device-side circuit 40 may be configured to cut off the power. is there.

[0022]

As described above, according to the present invention, transmission between devices via an optical fiber can be performed sequentially while amplifying an optical signal by an optical amplifier, so that the optical signal is not attenuated. , With expandability close to linear coupler connection,
An optical data bus connection configuration can be realized. Since the data bus interface is mounted on a device including a power supply, power can be easily supplied from the device to the optical amplification means.

According to the present invention, a delay means for providing a delay equivalent to that of the optical amplification means is provided in parallel with the optical amplification means, and a part of the optical signal is branched and then delayed and mixed. The optical signal can be transmitted without causing distortion. Even if the operation of the optical amplifying means stops due to equipment failure, the optical signal is transmitted to the downstream data bus interface by transmitting the optical signal through the delay means, and the optical signal is transmitted to the downstream optical amplifying means. Can be amplified to prevent a situation in which an optical signal is not transmitted to a downstream device due to a device failure, thereby improving reliability.

Further, according to the present invention, it is possible to detect the presence or absence of a failure in the optical amplifying means by providing the failure detecting means. Therefore, when the optical amplifying means fails, measures such as stopping the optical amplifying means are taken. In addition, it is possible to eliminate the influence of the failure of the optical amplifying means and to enhance the reliability.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a schematic configuration of a data bus interface 30 according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating an optical data bus connection configuration configured using the data bus interface 30 of the embodiment of FIG. 1;

FIG. 3 is a diagram illustrating a configuration of a coupler 32 according to the embodiment of FIG. 1;

FIG. 4 is a block diagram showing a schematic configuration of a data bus interface 60 according to another embodiment of the present invention.

FIG. 5 is a block diagram showing a schematic configuration of a data bus interface 70 according to still another embodiment of the present invention.

FIG. 6 is a diagram showing a state in which a plurality of devices mounted on an aircraft are connected by optical fibers.

FIG. 7 is a diagram illustrating an optical data bus connection configuration in which optical fibers are connected using a linear coupler.

[Explanation of symbols]

 30, 60, 70 Data bus interface 31 Input side connector 32 Coupler 32a, 39 Optical fiber 32b Fusion part 33 Optical amplifier 34 Output side connector 35, 36 Main bus optical fiber 37 EO transceiver 38, 71 OE transceiver 40 Equipment Side circuits 41 to 44 Equipment 61 First coupler 62 Second coupler 63 Third coupler 64 Delay fiber 72 Failure detection circuit

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[Procedure amendment]

[Submission date] February 22, 1999

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

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[Claims]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

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[0008]

SUMMARY OF THE INVENTION The present invention relates to an aircraft optical signal transmission device for connecting equipment mounted on an aircraft by an optical fiber so that an optical signal can be transmitted. A part of the mixing and branching optical fiber is fused to a connecting optical fiber through which an optical signal input to the input side connecting means and an optical signal input to the input side connecting means are formed to form a coupler. Is converted into an optical signal, input from one end of the optical fiber for mixing and branching, mixed by a coupler, a part of the optical signal is branched by the coupler and output from the other end of the optical fiber for mixing and branching, Using the mixing and branching means for converting to an electric signal and inputting to the device, and using the power supplied from the device,
An optical signal transmission device for an aircraft, comprising: an optical amplifying unit that amplifies an optical signal from the mixing / branching unit; and an output side connection unit that is connected to an output side of the optical amplification unit and that can connect an optical fiber. is there.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0009

[Correction method] Change

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According to the present invention, an optical signal input from an optical fiber connectable to the input-side connecting means is guided to the optical amplifying means via the optical fiber for connection of the mixing / branching means, and the output of the optical amplifying means is output. Output can be made to the optical fiber from the output side connection means. In the mixing / branching unit, a part of the mixing / branching optical fiber is fused to the connection optical fiber to form a coupler, and an electric signal from the device is converted into an optical signal to convert the one end of the mixing / branching optical coupler. Input, and mixed with an optical signal input from an optical fiber for connection by a coupler, a part of the optical signal is branched by the coupler, output from the other end of the optical coupler for mixing and splitting, and converted into an electric signal. , Input to the device. The optical signal output to the optical fiber connected to the output side connection means is amplified by the optical signal amplification means, and the power required for the amplification is supplied from the device. If an optical fiber is connected to the input side connection means and the output side connection means, and the optical fiber connection between the output side connection means on the upstream side and the input side connection means on the downstream side is sequentially repeated with respect to the transmission of the optical signal, linear It has the same expandability as that of coupler connection, and can be amplified by an optical amplifier so that the optical signal is less attenuated and transmitted sequentially.

[Procedure amendment 4]

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[Correction target item name] 0010

[Correction method] Change

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Further, the present invention relates to an aircraft optical signal transmission apparatus for connecting between equipment mounted on an aircraft by an optical fiber so that an optical signal can be transmitted, and an input side connecting means capable of connecting an optical fiber. And an optical signal input to the input side connection means is guided, converts an electric signal from the device into an optical signal and mixes it, branches a part of the optical signal, converts it into an electric signal, and inputs it to the device. Mixing / branching means, optical amplifying means for amplifying an optical signal from the mixing / branching means using power supplied from the device, and output-side connecting means connected to the output side of the optical amplifying means and capable of connecting an optical fiber A branching unit provided between the mixing and branching unit and the optical amplifying unit, for branching the optical signal from the mixing and branching unit, and a delay for giving a delay equivalent to that of the optical amplifying unit to the optical signal branched by the branching unit. Means,
Mixing means provided between the optical amplifying means and the output-side connecting means, for mixing the optical signal given by the delay means with the optical signal output from the optical amplifying means and outputting to the output-side connecting means. An optical signal transmission device for an aircraft, comprising:

[Procedure amendment 5]

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FIG. 4 shows a schematic configuration of a data bus interface 60 according to another embodiment of the present invention.
In the present embodiment, portions corresponding to the embodiment shown in FIG. 1 are denoted by the same reference numerals, and redundant description will be omitted. The data bus interface 60 of the present embodiment includes a first coupler 61, a second coupler 62, and a third coupler 63. The first coupler 61 is a coupler 3 of FIG.
Basically, the optical signal is mixed with the optical signal from the EO transceiver 37 and the optical signal input from the input connector 31, and a part of the optical signal is input to the device-side circuit 40 via the OE transceiver 38. Second coupler 6 serving as a branching means
2 branches the optical signal from the first coupler 61 into two systems. The third coupler 63, which is a mixing means, mixes two systems of optical signals. One of the two optical signals is amplified by the optical amplifier 33. The optical signals of the other systems of the two branched systems proceed as they are and consume time in the delay fiber 64. The delay fiber 64 is an optical fiber having a length necessary to simulate a time delay at the time of optical amplification in the optical amplifier 33. For this reason, the optical signal that has passed through the delay fiber 64 has the same time delay as the optical signal amplified by the optical amplifier 33, so that the waveform as a signal does not change when the optical signal is mixed by the third coupler 63 and merged. Can be

[Procedure amendment 6]

[Document name to be amended] Statement

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[Correction method] Change

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FIG. 5 shows a configuration of a data bus interface 70 according to still another embodiment of the present invention. In the present embodiment, portions corresponding to the embodiment of FIG. 1 or FIG. 4 are denoted by the same reference numerals, and redundant description will be omitted. This embodiment is different from the embodiment shown in FIG.
It has a configuration in which a transceiver 71 and a failure detection circuit 72 are added. The OE transceiver 71 branches a part of the optical signal output from the optical amplifier 33 by the fourth coupler 74 and inputs the converted signal to an electric signal. The failure detection circuit 72 compares the output from the OE transceiver 38, which converts the optical signal branched from the first coupler 61 into an electric signal, with the output from the OE transceiver 71, and detects a failure of the optical amplifier 33. The comparison in the failure detection circuit 72 is based on the optical amplifier 33
This is performed in consideration of the delay of the optical signal due to.

[Procedure amendment 7]

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[Correction method] Change

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[0022]

As described above, according to the present invention, the input and output by the optical signal to and from the equipment are performed by the coupler of the mixing / branching means. Since transmission between devices can be performed sequentially via an optical fiber while amplifying the optical signal by the optical amplifying means, the optical signal is not attenuated and has expandability close to that of a linear coupler connection. A data bus connection form can be realized. Since the data bus interface is mounted on a device including a power supply, power can be easily supplied from the device to the optical amplification means.

[Procedure amendment 8]

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[Correction method] Change

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Further, according to the present invention, a delay means for providing a delay equivalent to that of the optical amplification means is provided in parallel with the optical amplification means. The optical signal can be transmitted without causing distortion. Even if the operation of the optical amplifying means stops due to equipment failure, the optical signal is transmitted to the downstream data bus interface by transmitting the optical signal through the delay means, and the optical signal is transmitted to the downstream optical amplifying means. Can be amplified to prevent a situation in which an optical signal is not transmitted to a downstream device due to a device failure, thereby improving reliability.

[Procedure amendment 9]

[Document name to be amended] Drawing

[Correction target item name] Fig. 5

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FIG. 5

Claims (3)

[Claims] 1. An aircraft optical signal transmission device for connecting optical equipment so that optical signals can be transmitted between devices mounted on an aircraft, comprising: an input-side connecting means capable of connecting an optical fiber; A mixing / branching unit for guiding an optical signal input to the side connection unit, converting an electric signal from the device into an optical signal and mixing the same, branching a part of the optical signal, converting the signal into an electric signal, and inputting the signal to the device. And an optical amplifying means for amplifying an optical signal from the mixing / branching means using electric power supplied from the device; and an output side connecting means connected to an output side of the optical amplifying means and capable of connecting an optical fiber. An optical signal transmission device for an aircraft, comprising: 2. A branching means provided between the mixing / branching means and the optical amplifying means for branching an optical signal from the mixing / branching means, wherein the optical signal branched by the branching means is equivalent to the optical amplifying means. A delay means for providing a delay between the optical amplification means and the output side connection means, wherein the optical signal provided by the delay means is mixed with an optical signal output from the optical amplification means and output side connection is performed. 2. The optical signal transmission device for an aircraft according to claim 1, further comprising a mixing unit that outputs the signal to the unit. 3. An optical signal branched from said mixing / branching means is compared with an optical signal output from said optical amplifying means,
3. The airborne optical signal transmission device according to claim 1, further comprising a failure detection unit configured to detect a failure of the optical amplification unit based on a result of the comparison.