JPH1079745A - Optical communication cable and lan system using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical communication cable by which optical transmission is easily introduced without revising an existing LAN equipment. SOLUTION: This LAN system is provided with two optical cables 1, an electrooptic conversion circuit 2 and an optoelectric conversion circuit 3 connected respectively to one end of both the optical cables 1, a 1st electric connector 12 connected to the electrooptic conversion circuit 2 and the optoelectric conversion circuit 3 and a 2nd electric connector 12 connected to the optoelectric conversion circuit 3 and the electrooptic conversion circuit 2. The optical communication cable is used in place of a conventional unshielded twisted pair cable or in mixture with the non-shield twisted pair cable.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical cable which can be replaced with an existing electric cable in a LAN system without changing a conventional LAN device.

[0002]

2. Description of the Related Art In a LAN system, a cable for connecting LAN devices and an optical cable used have a small amount of signal attenuation, enable long-distance high-speed transmission, and are hardly affected by noise. However, such an optical cable is
At present, it is mainly used for trunk lines because it is expensive and requires special technology for installation.

[0003]

In recent years, the demand for high-speed LAN transmission has increased, and ATM (Asynchronous Transfer Mod
Standardization of high-speed transfer of 100 Mbps or more such as e) is progressing. In such an environment, when a new LAN is laid, an unshielded twisted pair cable (UTP cable) capable of supporting 155 Mbps is used to support future high-speed transmission. In addition, UTP of existing LAN
Efforts have been made to make effective use of cable facilities. This is because the UTP cable is inexpensive at a price and the construction is easy. Recently, an inexpensive optical cable using plastic has been developed and its transmission distance is 50 m to 10 m.
It has been extended to 0 m, making it possible to replace it with conventional UTP cables.

However, in order to introduce an optical cable,
Since it is necessary to replace a conventional LAN device (such as a HUB) with a device compatible with an optical cable, an optical cable cannot be easily introduced.

An object of the present invention is to provide an optical communication cable that can easily introduce optical transmission without changing existing LAN equipment.

[0006]

SUMMARY OF THE INVENTION An optical communication cable according to the present invention is an optical communication cable for transmitting signals between LAN devices, comprising first and second optical cables and the first and second optical cables. An electro-optical conversion circuit and a photoelectric conversion circuit connected to one end of the optical cable, and a first electrical connector connected to the electro-optical conversion circuit and the photoelectric conversion circuit,
A photoelectric conversion circuit and an electro-optic conversion circuit connected to the other ends of the first and second optical cables, respectively; and a second electrical connector connected to the photoelectric conversion circuit and the electro-optic conversion circuit. I do.

For example, an electric signal output from an electric connector of a LAN device is converted into an optical signal by an electro-optical conversion circuit, and the optical signal is transmitted to the other end by an optical cable. Further, this optical signal is converted into an electric signal by a photoelectric conversion circuit at the other end. This electric signal is transmitted as data to the partner LAN device via the electric connector.

As described above, according to the optical communication cable of the present invention, the introduction of optical transmission can be realized without changing the configuration of the conventional LAN equipment.

This optical communication cable includes the light-to-light conversion circuit and the light-to-light conversion circuit, and power supply means for supplying power to the light-to-light conversion circuit and the light-to-light conversion circuit.
This power supply means is, for example, an AC adapter.

[0010] It is also possible to provide a relay connector interposed between the electric connector and the LAN equipment, and to supply power from the power supply means via the relay connector and the electric connector. Thus, one power supply unit can be shared for a plurality of optical communication cables.

The LAN system according to the present invention has a
In the SE-T compliant LAN system, any one of the above-described optical communication cables is used as a cable connecting between the line concentrator and the terminal.

In this LAN system, an unshielded twisted pair cable may be used in combination with the optical communication cable as a cable connecting between the line concentrator and the terminal. As a result, the LAN system can be configured at low cost by using a conventional unshielded twisted pair cable for portions other than those requiring noise countermeasures.

In the case of an abnormality in which noise is present on a twisted pair cable, it is usually necessary to check the waveform on the cable and take measures against the noise, which took a long time. In such a case, the optical communication cable can be used as a tool for isolating a noise generation location. That is, the influence of noise is eliminated by installing the optical communication cable of the present invention instead of the twisted pair cable considered to be abnormal, and by confirming the operation in this state, the presence or absence of the influence of noise can be specified. If necessary, the optical communication cable can be left installed as a measure. In this way, it is possible to reduce the time required for troubleshooting as compared with the related art.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a schematic configuration of a LAN system in which an optical communication cable according to the present invention is introduced. This LAN system is based on IEEE80 called 10BASE-T.
It conforms to 2.3 Ethernet standard specifications.
The standard specifies that 10B using a coaxial cable as a transmission line
There are ASE5 and 10BASE2, but 10BASE-T uses unshielded twisted pair cable as the transmission line.
Has the advantages of being inexpensive, simple, and easy to maintain.

In a 10BASE-T LAN, a UTP cable is laid out in a star shape centering on a hub (HUB) and connected to a terminal such as a personal computer via an electrical connector called an RJ-45 modular jack. It has become.

The LAN system shown in FIG.
8 are connected to each other by a hub 6 which is a concentrator. FIG. 1 shows a state in which a conventional UTP cable 5 and an optical communication cable 11 of the present invention are used together. That is, the terminal 7 and the HUB 6 are connected by the optical communication cable 11,
The terminal 8 and the HUB 6 are connected by the UTP cable 5. Of course, the optical communication cable 11 may be used instead of the UTP cable 5. The optical communication cable 11 includes two plastic optical cables 1 for transmission and reception, an electro-optical conversion circuit 2 at one end thereof, a photoelectric conversion circuit 3 at the other end, and an electrical connector electrically connected to these circuits 2 and 3. (RJ45 modular jack) 12. Power is supplied from the AC adapter 4 to the unit 13 including the light-to-light conversion circuit 2 and the photoelectric conversion circuit 3.

HUB 6 has a plurality of electrical connectors 14 for receiving electrical connectors 12. On the backbone port side of HUB6, for connection to another HUB (not shown), or 10BASE5 or 10BASE2
May be provided with a port 15 for connection to a coaxial cable.

Between the terminal 7 and the HUB 6, an electric signal output from one terminal is converted into an optical signal by the electro-optical conversion circuit 2. This optical signal is transmitted through the plastic optical cable 1, returned to the electrical signal again by the photoelectric conversion circuit 3 on the other side, and input to the other side. As described above, the conventional UTP 6 and the terminal 7 are configured without any change.
The cable can be replaced with the present optical communication cable.

In the embodiment shown in FIG. 1, an AC adapter 4 is provided at each end of each optical communication cable 11, but when the number of optical communication cables 11 increases, the number of AC adapters 4 becomes smaller. However, there is a problem that the number also increases accordingly.

FIG. 2 shows a configuration in which a power supply adapter (relay connector) 9 is provided to solve this problem.
In this case, unlike the embodiment of FIG.
Is not directly connected to the optical communication cable 11 but supplies power to the optical communication cable 11 via the power supply adapter 9. With this configuration, even if the number of optical communication cables 11 increases, one AC adapter may be used for one power supply adapter 9 at one end of the optical communication cable 11. In the example of FIG. 2, the power supply adapter 9 is H
It has a plurality of electrical connectors 12 corresponding to the electrical connector 14 of the UB 6 and a plurality of connectors 24 corresponding to the electrical connector 22 of the optical communication cable 11. The electric connector 24 of the power supply adapter 9 and the electric connector 22 of the optical communication cable 11 have built-in power supply lines (not shown) in addition to signal lines of the connectors 12 and 14. Also in this case, there is no need to change the configurations of the HUB 6 and the terminal 7.

The optical communication cables 11 of the present invention are bundled into several bundles, and the lines for each zone are concentrated from a concentrator panel (not shown) to a zone box (not shown: bundled from the concentrator panel). Can also be used for wiring up to a terminal that distributes the information to each terminal in the zone. In this case, the power supply of the zone box can be used instead of the AC adapter 4 in FIG.

As shown in FIG. 1, the UT is connected to the LAN system.
When using the P cable 5, the UTP cable 5
They are susceptible to noise, and may cause malfunction if they pass near power lines or are laid in parallel with power line cables over long distances. In addition, the problem of radiating harmful electromagnetic waves from UTP cables has recently been highlighted. When the noise related to the UTP cable 5 is suspected as the cause of the failure that has occurred in the LAN system, the UTP cable 5 is replaced with the optical communication cable 11 and the occurrence of the failure is compared. It can be easily confirmed whether or not the noise is a cause of the failure. Therefore, the optical communication cable of the present invention can also be used as a tool for specifying a noise fault location. Further, if the optical communication cable of the present invention is used as it is instead of the UTP cable that caused the failure, it can be used as a noise suppression cable.

[0024]

According to the present invention, it is possible to provide an optical communication cable which can easily introduce optical transmission without changing existing LAN equipment. Further, this optical communication cable can be used as a tool for specifying a location of a noise failure or as a cable for noise suppression.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a schematic configuration of a LAN system using an optical communication cable according to the present invention.

FIG. 2 is an explanatory diagram showing another example of a power supply unit for supplying power to the optical communication cable of FIG. 1;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Optical cable, 2 ... Light-to-light conversion circuit, 3 ... Photoelectric conversion circuit, 4 ... AC adapter, 5 ... Unshielded twisted pair cable (UTP cable), 6 ... HUB, 7 ... Terminal, 8
... Terminal, 9 ... Power supply adapter (relay connector), 11
... optical communication cable, 12 ... electric connector, 13 ... unit, 14 ... electric connector, 15 ... port, 22 ... electric connector, 24 ... electric connector.

Claims (6)

[Claims] 1. An optical communication cable for transmitting a signal between LAN devices, comprising: a first and a second optical cable; and an electro-optical conversion circuit connected to one end of the first and the second optical cable, respectively. A photoelectric conversion circuit, a first electrical connector connected to the first electro-optical conversion circuit and the photoelectric conversion circuit, and a photoelectric conversion circuit and an electro-optical conversion circuit connected to the other ends of the first and second optical cables, respectively. And a second electrical connector connected to the photoelectric conversion circuit and the electro-optical conversion circuit. 2. The light-to-light conversion circuit and the photoelectric conversion circuit,
The optical communication cable according to claim 1, further comprising a power supply unit configured to supply power to the photoelectric conversion circuit and the electro-optical conversion circuit. 3. The optical communication cable according to claim 2, wherein said power supply means is an AC adapter. 4. A relay connector interposed between the electrical connector and the LAN device, wherein power is supplied from the power supply means via the relay connector and the electrical connector. The optical communication cable according to claim 2. 5. A LAN system according to claim 10, wherein the optical communication cable according to any one of claims 1 to 4 is used as a cable for connecting a concentrator and a terminal in a 10BASE-T compliant LAN system. 6. The LAN system according to claim 5, wherein an unshielded twisted pair cable is used in combination with said optical communication cable as a cable connecting between said line concentrator and said terminal.