KR100347127B1 - Method for optical multiplexing and system for performming the same - Google Patents

Abstract

PURPOSE: An optical multiplexing method and system of performing the same is provided to multiplex dual paths by a single wavelength by making transmission and to receive portions be multiplexed through respective light splitting and coupling portions. CONSTITUTION: The first wavelength division multiplexor(150) receives output signals of the first and second light transmission parts(110,120) for transmitting optical signals of the first and second wavelength bands, respectively. The second wavelength division multiplexor(160) divides a received light signal to output a light signal of the first wavelength band to the first light receiving part(130) and the light signal of the second wavelength band to the second light receiving part(140). The first light division and coupling device(170) transfers an output signal of the first wavelength division multiplexor(150) through an optical cable(180) and outputs a signal received through the optical cable to the second wavelength division multiplexor(160). The third wavelength division multiplexor(200) receives output signals of the third and fourth light transmission parts(220,230) for transmitting optical signals of the first and second wavelength bands, respectively. The third wavelength division multiplexor(210) divides a received light signal to output a light signal of the first wavelength band to the third light receiving part(240) and the light signal of the second wavelength band to the fourth light receiving part(250). The second light division and coupling device(190) transfers an output signal of the third wavelength division multiplexor through an optical cable(180) and outputs a signal received through the optical cable to the fourth wavelength division multiplexor.

Description

Method for optical multiplexing and system for performming the same

The present invention relates to an optical multiplexing method and a system for performing the same, and more particularly, to an optical multiplexing method for multiplexing an optical signal having a single wavelength into a light transmission path and a light receiving path using a linear characteristic of light, and a system for performing the same. .

In general, optical communication is a communication method of transmitting light using an optical fiber, unlike a wired communication using a metal wire or a wireless communication using a free space. In such an optical communication system, an electric signal is converted into an optical signal on the transmitting side and transmitted to the receiving side through an optical cable which is a transmission medium, and the receiving side converts the transmitted optical signal into an electrical signal.

Wavelength Division Multiplexing (WDM) method among multiple methods for multiplexing the optical communication method combines optical signals emitted by a plurality of light emitting devices having different wavelengths at the transmitting side into an optical combiner to form a single optical fiber cable. It is a method of transmitting and separating the multiplexed optical signal by the optical splitter at the receiving side.

Wavelength division multiplexing enables bidirectional transmission, simultaneous transmission of heterogeneous signals (e.g., analog video signals and digital video signals), easy extension of lines without line extension, and multiple transmission channels. It can be transmitted by dividing it into channels, so it can have a large capacity.

Therefore, recent communication system manufacturers are continuously researching and developing more reliable optical communication systems using optical communication methods, and various multiplexing methods using optical communication methods have been attempted.

Applicant's Korean Patent Application No. 98-18121 describes a three-path optical multiplexing device including a transmission, reception path, and reception diversity path at two wavelengths. Patent application No. 98-18121 is a technique suitable for use when connecting by optical communication between a base station using a CDMA method and a remote small base station.

Patent application No. 98-18121 discloses that an optical signal of the first and second transmission and reception units 10 and 20 for transmitting and receiving an optical signal of a first wavelength band (1310 nm) on one communication side is a first light distribution. And a first wavelength division multiplexer 50 through a combiner 40. The first optical distribution and combiner 40 provides a single path of optical signal. The signals of the third transmission and reception unit 30 for transmitting and receiving the optical signals of the first wavelength band 1310 nm and the second wavelength band 1550 nm are configured to be directly input to the first wavelength division multiplexer 50. In the first wavelength division multiplexer 50, a method of multiplexing an input optical signal by the WDM method, transmitting the optical signal to the optical cable 60, and receiving the signal on the opposite communication side is described.

No. 98-18121 by the applicant has described three path multiplexing schemes that can be applied to a CDMA communication system requiring a transmission path, a reception path, and a diversity path with two wavelengths. There is a need for an optical multiplexing scheme in which a path and a reception path are paired.

The present invention has been invented to meet the above necessity, and multiplexes the two paths of the transmission path and the reception path by a single wavelength by allowing a pair of transmitters and receivers to be multiplexed through respective light distribution and combiners. An object of the present invention is to provide a light multiplexing method and a system for performing the same.

1 is a block diagram showing the configuration of an optical multiplexing system according to the present invention.

2 is a block diagram illustrating a configuration of an optical multiplexing system according to another exemplary embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

110,310: first light transmitting part 120,340: second light transmitting part

130,320: first light receiving unit 140,330: second light receiving unit

150,370: first wavelength division multiple part 160,390: second wavelength division multiple part

170,350: First optical distribution and combiner 180,380: Optical cable

190,360: second optical splitter and combiner 200: second wavelength division multiplex

210: fourth wavelength division multiple part 220,420: third light transmitting part

230,450: fourth light transmitting unit 240,430: third light receiving unit

250,440: fourth light receiving unit 400: third light distribution and combiner

410: fourth optical distribution and coupler

The present invention for performing the above object,

Optically combining an optical signal of a first wavelength band and an optical signal of a second wavelength band different from the first wavelength band by the device A by using WDM to perform wavelength division multiplexing;

Separating the transmission path and the reception path by using the linear characteristics of the wavelength division multiplexed optical signal and transmitting them to the B device through the optical cable;

Receiving an optical signal transmitted to the B device through an optical cable into a transmission path and a reception path, and splitting the optical signal by the WDM method to receive an optical signal in a first wavelength band and an optical signal in a second wavelength band;

Optically combining the first wavelength band and the optical signal in the second wavelength band different from the first wavelength band by a WDM method to perform wavelength division multiplexing;

Separating the transmission path and the reception path by using the linear characteristics of the wavelength division multiplexed optical signal and transmitting them to the A device through the optical cable; And

The optical signal transmitted to the A device through the optical cable is divided into a transmission path and a reception path, and the optical signals are distributed by the WDM method to receive the optical signal in the first wavelength band and the optical signal in the second wavelength band, respectively.

In addition, the optical multiplexing system according to the present invention receives the output signal of the first transmitter for transmitting the optical signal of the first wavelength band and the second transmitter for transmitting the optical signal of the second wavelength band to optically combine by WDM method A first wavelength division multiplexing unit for splitting the received optical signal by the WDM method to divide the optical signal in the first wavelength band to the first light receiving unit and to output the second optical signal in the second wavelength band to the second light receiving unit Central;

A first optical splitter and combiner for transmitting the optical signal output from the first wavelength division multiplex through an optical cable connected to an embedded transmission path, and outputting the optical signal received through the optical cable to a second wavelength division multiplex;

A third wavelength division multiple part for receiving an output signal of a third transmitter for transmitting an optical signal of the first wavelength band and a fourth transmitter for transmitting an optical signal of the second wavelength band for optical coupling by WDM method; A fourth wavelength division multiple part for optically separating the optical signal by the WDM method and outputting the optical signal in the first wavelength band to the third light receiver and the optical signal in the second wavelength band to the fourth light receiver; And,

And a second optical splitter and a combiner for transmitting the optical signal output from the third wavelength division multiplex through an optical cable connected to an embedded transmission path and outputting the optical signal received through the optical cable to the fourth wavelength division multiplex. do.

According to the present invention, the efficiency of an optical communication system is improved by multiplexing a path into a transmission path and a reception path with one wavelength.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings of the present invention.

1 is a block diagram illustrating a configuration of an optical multiplexing apparatus according to the present invention, and FIG. 2 is a block diagram illustrating a configuration of an optical multiplexing system according to another embodiment of the present invention.

The optical multiplexing device according to the present invention is configured to provide a transmission path and a reception path with a single wavelength. To this end, as shown in FIG. 1, the A device side in communication has a first transmitter 110 for transmitting an optical signal in a first wavelength band and a second transmitter for transmitting an optical signal in a second wavelength band different from the first wavelength band. The transmitter 120 is connected to the first wavelength division multiplexer 150 to input an optical signal. The first light receiving unit 130 for receiving the optical signal in the first wavelength band and the second light receiving unit 140 for receiving the optical signal in the second wavelength band different from the first wavelength band are received from the second wavelength division multiplexer 160. It is connected to receive a signal.

The first wavelength division multiplexer 150 is connected to input an optical signal to the first light distribution and combiner 170 that provides a single path that is different depending on the transmission and reception modes, and the second wavelength division multiplexer 160 ) Is connected to receive an optical signal from the first light distribution and combiner 150.

The first optical splitter and combiner 170 is connected to transmit and receive an optical signal with the second optical splitter and combiner 180 on the B device side via the optical cable 180. The second light distribution and combiner 180, which provides a single path different according to the transmission and reception modes of the B device, is connected to the third wavelength division multiplexer 200 and the fourth wavelength division multiplexer 210. The third wavelength division multiplexer 200 is connected to input an optical signal to the second optical splitter and combiner 190, and the fourth wavelength division multiplexer 210 is adapted to receive light from the second optical splitter and combiner 190. It is connected to receive a signal.

The third wavelength division multiplexer 200 may include a third transmitter 220 for transmitting an optical signal of a first wavelength band and a fourth transmitter 230 for transmitting an optical signal of a second wavelength band different from the first wavelength band. It is connected to receive an optical signal from. The fourth wavelength division multiplexing unit 210 may be configured to emit light into a third light receiving unit 240 for receiving an optical signal in a first wavelength band and a fourth light receiving unit 250 for receiving an optical signal in a second wavelength band different from the first wavelength band. Is connected to output a signal.

In this case, the first optical splitter and combiner 170 and the second optical splitter and combiner 180 use an apparatus that separates an optical signal in one wavelength band into two paths by using a linear characteristic of light. Such a device may be one of a splitter for separating optical signals, a circulator for converting an optical path by a magnetic field, and a circulator and a direct coupler for securing a transmission path and a reception path. .

Therefore, the optical multiplexing system of the present invention multiplexes an optical signal of one wavelength band to each of a transmission path and a reception path using a linear characteristic of light, and thus can be multiplexed into four paths using two wavelength bands, Using the wavelength band can be multiplexed into six paths. That is, by using N wavelength bands, multiplexing is possible in 2N paths.

In the optical multiplexing device according to the preferred embodiment of the present invention configured as described above, when transmitting from the A device, the first and second transmitters 110 and 120 convert the signals to be transmitted into optical signals having different wavelength bands. The output optical signal is coupled to the optical combiner by the WDM method through the first wavelength division multiplexer 150 and input to the first optical splitter and combiner 170. The first optical splitter and combiner 170, which is configured to provide different paths according to the transmission and reception modes, transmits the optical cable 180 through the transmission path to the optical signal output from the first wavelength division multiplexer 150. To the B device. That is, the first optical splitter and combiner 170 is a device of one of a splitter, a circulator, and a direct coupler having a transmission path and a reception path separately by using the linear characteristics of the optical signal. Because of this configuration, the optical signal output from the first wavelength division multiplexer 150 is transmitted along the transmission path.

The optical signal transmitted to the device B through the optical cable 180 is input to the fourth wavelength division multiplexer 200 along the receiving path of the second optical splitter and combiner 180. The second optical splitter and combiner 190 is composed of one of a splitter, a circulator, and a direct coupler having a transmission path and a reception path separately by using the linear characteristics of the optical signal. Therefore, the optical signal transmitted through the optical cable 180 is input to the fourth wavelength division multiplexer 200 along the transmission path.

The optical signal input to the fourth wavelength division multiplexer 200 is separated into an optical splitter and input to the third light receiver 240 and the fourth light receiver 250 configured to receive different wavelengths. The third light receiver 240 and the fourth light receiver 250 convert the optical signal in the input wavelength band into a transmission signal.

In addition, when transmitting from the device B, the optical signals output from the third transmitter 220 and the fourth transmitter 240 are multiplexed through the third wavelength division multiplexer 200, and the second optical splitter and The combiner 180 is transmitted to the first optical splitter and combiner 170 via an optical cable 180.

The first optical splitter and combiner 170 receives the received optical signal through the second wavelength division multiplexer 160 and is input to the first light receiver 130 and the second light receiver 140 according to the wavelength band.

The first optical splitter and combiner 170 transmits the output signal of the first wavelength division multiplexer 150 through the optical cable 180 when transmitting the A device, and through the optical cable 180 when receiving the A device. The transmitted optical signal is input to the second wavelength division multiplexer 160.

The second optical splitter and combiner 180 transmits the output signal of the third wavelength division multiplex 200 through the optical cable 180 when transmitting the B device, and the optical cable 180 when receiving the B device. The optical signal transmitted through the input is input to the fourth wavelength division multiplexer 210.

According to another embodiment of the optical multiplexing device according to the present invention, as shown in FIG. 2, the first light transmitting part 310 and the first light receiving part 320 for transmitting and receiving optical signals in the first wavelength band are respectively provided on the A device side. And the first light distribution and coupler 350 are connected. The first light distribution and combiner 350 provides different paths to the first transmitter 310 and the first receiver 320. Similarly, a second light distribution and combiner 360 is connected to the second light transmitting portion 340 and the second light receiving portion 330 for transmitting and receiving optical signals in the second wavelength band having different wavelengths.

The first optical splitter and combiner 350 and the second optical splitter and combiner 360 are connected to the first wavelength division multiplexer 370 to transmit and receive an optical signal. The first wavelength division multiplexer 370 is connected to transmit and receive a signal with the second wavelength division multiplexer 390 through the optical cable 380. The second wavelength division multiplexer 390 is connected to transmit and receive an optical signal with the third optical splitter and combiner 400 and the fourth optical splitter and combiner 410, respectively. A third light transmitting unit 420 and a third light receiving unit 430 for transmitting and receiving an optical signal in a first wavelength band are connected to the third light distribution and combiner 400, and to the fourth light distribution and combiner 410. The fourth transmitter 440 and the fourth receiver 450 for transmitting and receiving the optical signal in the second wavelength band are connected.

In other words, in another embodiment of the present invention, the first, second, third and fourth light distribution and combiner 350, 360, 400, 410 are connected to the transmitter and the receiver in each of the transmission and reception paths. The first, second, third and fourth light distribution and combiners 350, 360, 400 and 410 transmit and receive optical signals with the first and second wavelength division multiplexers 370 and 390. To be connected.

The first optical splitter and combiner 350 and the third optical splitter and combiner 400 are configured to transmit and receive optical signals in the first wavelength band, and the second optical splitter and combiner 360 and the fourth optical splitter and combiner 410 is configured to transmit and receive an optical signal in a first wavelength band.

Operation of the optical multiplexing device according to another embodiment of the present invention is the same as the embodiment shown in FIG. Another embodiment of the optical multiplexing apparatus multiplexes an optical signal according to a transmission and reception path determined by passing through a specific light distribution and combiner (350, 360, 400, 410) according to the wavelength band at each transmitter and receiver. The multiplexed optical signal is transmitted and received.

In addition, the optical multiplexing system according to another embodiment of the present invention multiplexes an optical signal of one wavelength band to each of the transmission path and the reception path using the linear characteristics of the light, thereby multiplexing into four paths using two wavelength bands. Using three wavelength bands can be multiplexed into six paths. That is, by using N wavelength bands, multiplexing is possible in 2N paths.

As described above, the present invention enables the optical multiplexing of two transmission paths and two reception paths to an optical signal in a certain wavelength band, thereby implementing an efficient communication system.

Although the preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, the present invention is not limited thereto and may be improved or modified by those skilled in the art within the scope of the technical idea of the present invention.

Claims (7)

Iv) in the device A, when the optical signal of the first wavelength band and the optical signal of the second wavelength band which are different from the first wavelength band are input, optically couple by wavelength division multiplexing by WDM; Ii) separating the transmission path and the reception path by using the linear characteristics of the wavelength division multiplexed optical signal and transmitting them to the B device through the optical cable; Iv) receiving the optical signal transmitted to the B device through the optical cable by separating the transmission path and the reception path and splitting the light by the WDM method to receive the optical signal in the first wavelength band and the optical signal in the second wavelength band, respectively; Iv) optically combining the first wavelength band and the optical signal in the second wavelength band with the second wavelength band by the WDM method to perform wavelength division multiplexing; Iv) separating the transmission path and the reception path by using the linear characteristics of the wavelength division multiplexed optical signal and transmitting them to the A device through the optical cable; And (Iii) receiving the optical signal transmitted to the A device through the optical cable into a transmission path and a reception path, and splitting the optical signal by the WDM method to receive the optical signal in the first wavelength band and the optical signal in the second wavelength band, respectively; Light multiplexing method comprising a. Receives the output signal of the first transmitter 110 for transmitting the optical signal of the first wavelength band (1550nm) and the second transmitter 110 for transmitting the optical signal of the second wavelength band (1310nm) by the WDM method A first wavelength division multiple part 150 for optical coupling; The optical signal of the first wavelength band (1550nm) is optically separated by the WDM method, and the optical signal of the second wavelength band (1310nm) is output to the second light receiving unit (140). 2 wavelength division multiplexing unit 160; The optical signal output from the first wavelength division multiplexer 150 is transmitted through the optical cable 180 connected to the embedded transmission path, and the optical signal received through the optical cable 180 is transmitted to the second wavelength division multiplexer ( A first light distribution and combiner 170 output to 160; By receiving the output signal of the third transmitter 220 for transmitting the optical signal of the first wavelength band (1550nm) and the fourth transmitter 230 for transmitting the optical signal of the second wavelength band (1310nm) by the WDM method A third wavelength division multiple part 200 for coupling light; The optical signal of the first wavelength band (1550nm) is optically separated by the WDM method, and the optical signal of the second wavelength band (1310nm) is output to the fourth light receiving unit 250. A fourth wavelength division multiplexer 210; And, The optical signal output from the third wavelength division multiplexer 200 is transmitted through an optical cable 180 connected to an embedded transmission path, and the optical signal received through the optical cable 180 is transmitted to a fourth wavelength division multiplexer ( And a second optical distribution and combiner (190) for outputting to the optical multiplexing system. The optical multiplexing system according to claim 2, wherein the first optical splitter and combiner (170) and the second optical splitter and combiner (190) are splitters for separating optical signals. 3. The optical multiplexing system of claim 2, wherein the first light splitter and combiner (170) and the second light splitter and combiner (190) are circulators. 3. The optical multiplexing system of claim 2, wherein the first light splitter and coupler (170) and the second light splitter and coupler (190) are direct couplers. A first optical distribution connected to the first transmitting unit 310 and the first receiving unit 320 for transmitting and receiving the optical signal in the first wavelength band, and for transmitting the optical signal in different paths according to transmission and reception modes; Coupler 350; Transmitting optical signals through different paths according to transmission and reception operations by being connected to a second transmitter 340 and a second receiver 330 for transmitting and receiving an optical signal of a second wavelength band different from the first wavelength band. A second light distribution and coupler 360 for; A first wavelength division multiplexer 370 configured to transmit and receive signals with the first optical splitter and combiner 350 and the second optical splitter and combiner 360 to distribute and combine the optical signal in a WDM manner; A second wavelength division multiplexer 390 connected to transmit and receive a signal through the first wavelength division multiplexer 370 and an optical cable 380 to distribute and combine an optical signal in a WDM manner; A second light transmission unit 420 connected to the second wavelength division multiplexer 390 to transfer the optical signal of the first wavelength band to the third transmitter 420 and the third receiver 430 in different paths according to transmission and reception modes. 3 light distribution and combiner 400; A second signal connected to the second wavelength division multiplexer 390 for transmitting the optical signal of the second wavelength band to the fourth transmitter 450 and the fourth receiver 440 through different paths according to a transmission and reception mode. 4 Light multiplexing device comprising a light distribution and combiner (410). 7. The optical multiplexing device according to claim 2 or 6, wherein the optical multiplexing device is configured by adding a light distribution and a combiner and a wavelength division multiplexing unit to multiplex with 2N paths with N wavelengths.