KR100594900B1 - Wavelength Division Multiplexing Passive Optical Network System adopted dual ring structure - Google Patents

Abstract

The present invention relates to a multi-ring structured wavelength division multiplexing passive optical network system, and employs a plurality of ring-type optical communication lines in a wavelength division multiplexing passive optical network system to accommodate a large number of subscribers using the same system. At the same time, a plurality of signal compensators are connected and implemented by using an optical coupler during multiplexing / demultiplexing periods of a plurality of optical communication lines and a central base station, thereby causing insertion loss, optical cable degradation, etc., caused by interfacing various devices on the plurality of optical communication lines. It is to properly compensate for the losses caused by various environmental factors such as the losses caused by them.

Passive Optical Network (PON), Loss, Compensation

Description

Wavelength Division Multiplexing Passive Optical Network System {Wavelength Division Multiplexing Passive Optical Network System adopted dual ring structure}

1 is a schematic diagram of a multi-ring structured wavelength division multiplexing passive optical network system according to the present invention;

2 is a block diagram of a first embodiment of a signal compensator of a multi-ring structure wavelength division multiplexing passive optical network system according to the present invention;

3 is a block diagram of a second embodiment of a signal compensator of a multi-ring structure wavelength division multiplexing passive optical network system according to the present invention;

4 is a configuration diagram of a third embodiment of a signal compensator of a multi-ring structure wavelength division multiplexing passive optical network system according to the present invention;

5 is a configuration diagram of a fourth embodiment of a signal compensator of a multi-ring structure wavelength division multiplexing passive optical network system according to the present invention;

6 is a block diagram of a fifth embodiment of a signal compensator of a multi-ring structure wavelength division multiplexing passive optical network system according to the present invention;

7 is a configuration diagram of a sixth embodiment of a signal compensator of a multi-ring structure wavelength division multiplexing passive optical network system according to the present invention;

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

100a, 100b: optical communication line 200: central base station

210: light transmitting unit 220: light receiving unit

230: multiplexer / demultiplexer 240: optical circulator

300: local base station 310: optical branch / combiner

320: media converter 321a, 321b: optical circulator

400: optical coupler 500: signal compensator

510, 530, 610, 830: Optical Circulator 520, 710, 810, 820: 1 × 2 Coupler

540, 630, 730, 840: amplifier 620, 720: 2 × 2 coupler

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a multi-ring structured wavelength division multiplexing passive optical network system. In particular, the present invention relates to a wavelength division multiplexing passive optical network capable of compensating various losses such as connection node loss caused by various device interfaces on a plurality of optical communication lines. It is related to a network system.

Wavelength Division Multiplexing (WDM) is a method in which a central office (CO) assigns different wavelengths to each subscriber and transmits data at the same time. Each subscriber always uses the assigned wavelength to transmit data. Can send / receive This method not only can transmit a large amount of data to each subscriber, but also has the advantage of excellent communication security and easy performance improvement.

On the other hand, passive optical network (PON) is a method of constructing an optical subscriber network that allows a single optical line termination (OLT) to connect several optical network units (ONUs) by using a passive optical distribution element to the optical cable. That's the way. The passive optical network (PON) is transmitted from the central base station (CO) to the local base station (RN: Remote Node) through one optical fiber, divided into passive optical distribution elements in the local base station (RN), and transmitted to each subscriber through the optical fiber. do. That is, since the passive optical network (PON) is connected to a single optical fiber from the central base station (CO) to the regional base station (RN) installed in the neighboring area of the subscribers, and from the regional base station (RN) to each subscriber by an independent optical fiber, In addition, the cost of the cable can be relatively reduced compared to the one-to-one installation of the optical cable from the central base station (CO) to the subscriber.

The wavelength division multiplexing (WDM) technology and the passive optical network (PON) technology may be combined to implement a single wavelength division multiplexing (WDM) passive optical network (PON) system. Wavelength division multiplexing (WDM) passive optical network (PON) systems typically have redundant configurations to replace fiber failures or in the event of a failure of a particular channel's LD (for optical transmitter) or PD (for optical receiver). Redundancy structure is adopted.

In the patent application No. 2003-98904 filed by the applicant of the present invention (December 29, 2003), it is possible to extend the life of the light source and lower the transmission error rate of the data packet by blocking the light that can flow into the light source. A wavelength division multiplexing (WDM) type passive optical network (PON) system has been proposed, and in Patent Application No. 2004-24234 (April 08, 2004), which is generated by interfacing various devices on a ring optical communication line, We propose a wavelength division multiplexing (WDM) passive optical network (PON) system that can adequately compensate for losses caused by various environmental factors such as loss due to insertion loss and fiber degradation.

The present inventors can adopt a plurality of ring-type optical communication lines in a wavelength division multiplexing passive optical network system based on the technology previously filed by the applicant of the present invention to accommodate a larger number of subscribers using the same system. At the same time, multi-ring structured wavelength division multiplexing passive optical network system that can adequately compensate for losses caused by various environmental factors such as insertion loss caused by interface of various devices on optical communication line, loss due to optical cable deterioration, etc. I started to study about.

SUMMARY OF THE INVENTION The present invention has been invented in view of the above, and by adopting a plurality of ring-type optical communication lines in a wavelength division multiplexing passive optical network system, it is possible to accommodate a larger number of subscribers using the same system and various environmental factors. It is an object of the present invention to provide a multi-ring structured wavelength division multiplexing passive optical network system capable of appropriately compensating for losses caused by the present invention.

According to an aspect of the present invention for achieving the above object, a multi-ring structure wavelength division multiplexing passive optical network system according to the present invention comprises a ring-shaped optical communication line; A plurality of optical transmitters for generating optical signals having different wavelengths, an optical receiver for receiving an optical signal having the same wavelength as that of the optical transmitter paired with the optical transmitter and converting the optical signal into an electrical signal; A multiplexer / demultiplexer for multiplexing and outputting optical signals having different wavelengths to the optical communication line, and demultiplexing and outputting the multiplexed optical signal input through the optical communication line, and outputting the optical signal output from a designated optical transmitter A central base station including a plurality of optical circulators for outputting to a multiplexer / demultiplexer and outputting an optical signal demultiplexed from the multiplexer / demultiplexer to a designated optical receiver; An optical branch / combiner for dropping only a signal having a wavelength of a specific band among the optical signals transmitted through the optical communication line and outputting the signal to the subscriber device and outputting the optical signal transmitted from the subscriber device to the optical communication line; A wavelength comprising at least one local base station comprising an optical circulator for outputting the optical signal dropped through the combiner to the optical receiver of the subscriber device and outputting the optical signal from the optical transmitter of the subscriber device to the optical splitter / coupler; A wavelength division multiplexing (WDM) passive optical network (PON) system, the wavelength division multiplexing passive optical network system comprising: a plurality of ring-shaped optical communication lines; A plurality of signal compensators connected to each of the ring-shaped optical communication lines to compensate for signals transmitted and received during the multiplexing / demultiplexing periods of the optical communication line and the central base station; A signal output from each of the signal compensators and connected to the multiplexing / demultiplexing periods of each of the plurality of signal compensators and the central base station to branch the signal output from the multiplexer / demultiplexer to each of the signal compensators, or output from each of the signal compensators It characterized in that it comprises an optical coupler for outputting to the multiplexer / demultiplexer.

Therefore, by adopting a plurality of ring-type optical communication lines in a wavelength division multiplexing passive optical network system, an insertion loss caused by interfacing various devices on the optical communication line while accommodating a larger number of subscribers than the existing system using the same system. In addition, it is possible to appropriately compensate for losses caused by various environmental factors such as loss due to fiber degradation.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily understand and reproduce the present invention.

1 is a schematic diagram of a multi-ring structured wavelength division multiplexing passive optical network system according to the present invention.

As shown in the figure, the multi-ring structure wavelength division multiplexing passive optical network system according to the present invention includes a plurality of ring-shaped optical communication lines 100a and 100b, a central base station 200, and a plurality of regional base stations 300. ), An optical coupler 400, and a plurality of signal compensators 500, wherein the central base station 200 includes a plurality of local base stations 300 through ring-shaped optical communication lines 100a or 100b. And network connection.

The central base station 200 is the same as the plurality of optical transmitters 210 for generating optical signals of different wavelengths and the optical transmitters 210 which are paired with each of the optical transmitters 210. It includes a plurality of light receiving unit 220 for receiving the optical signal of the wavelength and converts it to an electrical signal and outputs. In this case, the optical transmitter 210 may generate a single broadband wavelength without generating optical signals having different wavelengths, and may generate optical signals having different wavelengths using a grating element (not shown). Of course.

In addition, the central base station 200 multiplexes the optical signals of different wavelengths input through the optical circulators 240 and outputs them to the optical communication lines 100a or 100b, and inputs them through the optical communication lines 100a or 100b. And a multiplexer / demultiplexer 230 for demultiplexing the multiplexed optical signal to be output to the optical circulator 240.

In addition, the central base station 200 outputs the optical signal output from the designated optical transmitter 210 to the multiplexer / demultiplexer 230, and the optical signal demultiplexed by the multiplexer / demultiplexer 230 to be input. It includes a plurality of optical circulator 240 output to the designated light receiving unit 220.

The optical circulator 240 is an optical device designed so that light incident through an input port never returns back to the same port. This means that light from the light source does not flow back into the light source no matter which path it takes. Since the operation of the optical circulator 240 is described in detail in a patent filed by the applicant of the present invention, a detailed description thereof will be omitted.

For example, when port 1 of the optical circulator 240 is connected to the optical transmitter 210 and ports 2 and 3 are connected to the multiplexer / demultiplexer 230 and the optical receiver 220, respectively, each optical transmitter 210 is connected. The optical signal generated by the NX is multiplexed in the multiplexer / demultiplexer 230 through port 2 and transmitted to each local base station 300 through an optical communication line 100a or 100b, and a ring type optical communication line 100a or 100b. The optical signal circulated through is demultiplexed in the multiplexer / demultiplexer 230 and then flows into port 2 of each optical circulator 240 so that each optical receiver 220 receives an optical signal through port 3. will be. At this time, since the optical signal introduced through the port 2 does not return to the port 1 but is output through only the port 3, the phenomenon that the optical signal flows into the light source does not appear.

Therefore, a packet transmission error does not occur even at a low speed as well as a high speed data transmission.

The local base station 300 drops only a signal having a wavelength of a specific band among the optical signals transmitted through the optical communication line 100a or 100b and outputs the signal to a subscriber device (not shown) to the optical signal transmitted from the subscriber device. An optical splitter / combiner 310 for outputting the signal to the optical communication line 100a or 100b, and an optical signal dropped through the optical splitter / combiner 310 to an optical receiver of a subscriber device, and an optical transmitter of the subscriber device. And a plurality of optical circulators 321a and 321b for outputting an optical signal input from the optical splitter / combiner 310.

At this time, each local base station 300 can prevent the optical signal from being introduced into the optical transmitter of each subscriber device by the optical circulators 321a and 321b.

In the drawing, reference numeral 320 denotes a media converter, and since it is described in detail in the patent filed by the applicant of the present invention, a detailed description thereof will be omitted.

The optical coupler 400 is connected between each of the plurality of signal compensators 500 and the multiplexer / demultiplexer 230 of the central base station 200 to branch the signal output from the multiplexer / demultiplexer 230. The signal is output to each of the signal compensators 500 or the signals output from each of the signal compensators 500 are output to the multiplexer / demultiplexer 230.

The signal compensator 500 is connected to each of the ring-shaped optical communication lines 100a and 100b to be transmitted and received between the optical communication lines 100a and 100b and the multiplexer / demultiplexer 230 of the central base station 200. Compensate for each signal.

That is, the present invention adopts a plurality of ring-shaped optical communication lines 100a and 100b in a wavelength division multiplexing passive optical network system to accommodate a larger number of subscribers than the conventional system using the same system, and at the same time, the plurality of optical communication systems. A plurality of optical communication lines 100a are implemented by connecting a plurality of signal compensators 500 using the optical coupler 400 between the lines 100a and 100b and the multiplexer / demultiplexer 230 of the central base station 200. Compensation for the loss caused by various environmental factors, such as the insertion loss caused by the interface of the various devices on the 100b), the loss due to optical cable degradation, etc. are appropriately compensated.

2 is a block diagram of a first embodiment of a signal compensation unit of a multi-ring structure wavelength division multiplexing passive optical network system according to the present invention, and FIG. 3 is a signal compensation of a multi-ring structure wavelength division multiplexing passive optical network system according to the present invention. 4 is a configuration diagram of a third embodiment of a signal compensation unit of a multi-ring structure wavelength division multiplexing passive optical network system according to the present invention, and FIG. 5 is a configuration diagram of a multi-ring structure wavelength division multiplexing according to the present invention. 6 is a configuration diagram of a fourth embodiment of a signal compensation unit of a passive optical network system, FIG. 6 is a configuration diagram of a fifth embodiment of a signal compensation unit of a multiple ring structure wavelength division multiplexing passive optical network system according to the present invention, and FIG. 7 is a block diagram of a sixth embodiment of a signal compensator of a multi-ring structure wavelength division multiplexing passive optical network system according to an embodiment .

Specifically, according to the first embodiment of the multi-ring structure wavelength division multiplexing passive optical network system according to the present invention, the signal compensator 500 includes a first optical circulator 510 and a 1 × 2 coupler 520. ), A second optical circulator 530, and a pair of amplifiers 540.

The first optical circulator 510 is a signal output from the multiplexer / demultiplexer 230 of the central base station 200 and output through the optical coupler 400 and the multiplexing / of the central base station 200. The demultiplexer 230 transmits and receives signals input through the optical coupler 400 through different paths.

The 1 × 2 coupler 520 branches and outputs a signal transmitted to the optical communication line 100a or 100b, and receives a signal transmitted from the optical communication line 100a or 100b.

The second optical circulator 530 allows a signal input from the 1 × 2 coupler 520 and a signal output to the 1 × 2 coupler 520 to be transmitted and received through different paths.

The amplifier 540 is installed on two paths between the first optical circulator 510 and the second optical circulator 530 in opposite directions, and amplifies and compensates signals transmitted and received through these two paths.

That is, this first embodiment is implemented so that the optical signal reflected to the multiplexer / demultiplexer 230 and the optical communication line 100a or 100b of the central base station 200 is not introduced using two optical circulators 510 and 530. One port of the first optical circulator 510 is connected to the other end of the optical coupler 400 connected to the multiplexer / demultiplexer 230 of the central base station 200 and the other two ports are each It is connected to one side of a pair of amplifiers 540 installed in opposite directions to each other.

The two ports of the second optical circulator 530 are connected to the other side of the pair of amplifiers 540 installed in opposite directions, respectively, and the other one port of the second optical circulator 530 is the 1 × 2 coupler 520. Is connected to one end of

Two other branched ends of the 1 × 2 coupler 520 are connected to the optical communication line 100a or 100b, respectively.

Therefore, the optical signals transmitted and received between the multiplexer / demultiplexer 230 and the optical communication line 100a or 100b of the central base station 200 have different transmission paths by the two optical circulators 510 and 530. Signals transmitted and received by a pair of amplifiers 540 respectively installed in opposite directions on two transmission paths are amplified appropriately, and various environmental factors such as insertion loss and optical cable deterioration caused by interfacing various devices on the optical communication line. The losses caused by the factors are compensated appropriately.

The second to fourth embodiments to be described below have a structure in which the number of optical circulators is reduced and a coupler is used to minimize the cost increase caused by employing the two optical circulators of the first embodiment. Couplers are not advantageous in terms of stability compared to optical circulators, but have a good price-performance ratio in terms of loss compensation.

According to a second embodiment of a multi-ring structure wavelength division multiplexing passive optical network system according to the present invention, the signal compensator 500 includes an optical circulator 610, a 2 × 2 coupler 620, and a pair of amplifiers. 630.

The optical circulator 610 is a signal output from the multiplexer / demultiplexer 230 of the central base station 200 and output through the optical coupler 400, and the multiplexer / demultiplexer of the central base station 200 ( The signal input via the optical coupler 400 is transmitted and received through the different paths 230.

The 2x2 coupler 620 branches and outputs a signal transmitted to the optical communication line 100a or 100b, and branches and outputs a signal received from the optical communication line 100a or 100b.

The amplifier 630 is installed on two paths between the optical circulator 610 and the 2 × 2 coupler 620 in opposite directions, and amplifies and compensates signals transmitted and received through the two paths.

That is, the second embodiment is implemented by using one optical circulator 610 to prevent the optical signal reflected to the multiplexer / demultiplexer 230 of the central base station 200 from being introduced, one of the optical circulators 610. Is connected to the other end of the optical coupler 400 connected to the multiplexer / demultiplexer 230 of the central base station 200, and the other two ports are respectively connected to one side of a pair of amplifiers 630 installed in opposite directions. do.

The branched one end of the 2x2 coupler 620 is connected to the other side of the pair of amplifiers 630 installed in the opposite directions, and each of the other branched ends of the 2x2 coupler 620 is an optical communication line 100a or 100b).

Accordingly, optical signals transmitted and received between the multiplexer / demultiplexer 230 and the optical communication line 100a or 100b of the central base station 200 are different from each other by the optical circulator 610 and the 2 × 2 coupler 620. Signals transmitted and received by a pair of amplifiers 630 installed in opposite directions on two transmission paths, respectively, are amplified appropriately, and loss caused by insertion loss, optical cable deterioration, etc. caused by interfacing various devices on the optical communication line. Appropriate compensation for losses incurred by various environmental factors.

According to a third embodiment of a multi-ring structure wavelength division multiplexing passive optical network system according to the present invention, the signal compensator 500 includes a pair of 1 × 2 couplers 710, 2 × 2 couplers 720, and a pair. The amplifier 730 of the.

The 1 × 2 coupler 710 is output from the multiplexer / demultiplexer 230 of the central base station 200 to branch and output the signal output through the optical coupler 400, and the optical coupler 400 Receives a signal transmitted to the multiplexer / demultiplexer 230 of the central base station 200 via.

The 2 × 2 coupler 720 branches and outputs a signal transmitted to the optical communication line 100a or 100b, and branches and outputs a signal received from the optical communication line 100a or 100b.

The amplifier 730 is installed in opposite directions on two paths between the 1 × 2 coupler 710 and the 2 × 2 coupler 720 to amplify and compensate for a signal transmitted and received through these two paths.

That is, the third embodiment does not employ the optical circulator, and the reflected signal blocking efficiency is not superior to those of the first and second embodiments described above, but is implemented to minimize the cost. One end of the other end is connected to the other end of the optical coupler 400 connected to the multiplexer / demultiplexer 230 of the central base station 200, and the other end is branched to one side of a pair of amplifiers 730 installed in opposite directions to each other Each is connected.

The branched one end of the 2x2 coupler 720 is connected to the other side of the pair of amplifiers 730 installed in the opposite directions, and each of the other branched ends of the 2x2 coupler 720 is connected to the optical communication line 100a or 100b).

Accordingly, optical signals transmitted and received between the multiplexer / demultiplexer 230 and the optical communication line 100a or 100b of the central base station 200 are different by the 1 × 2 coupler 710 and the 2 × 2 coupler 720. Signals transmitted and received by a pair of amplifiers 730 each having a transmission path and installed in opposite directions on two transmission paths are amplified appropriately, and are caused by insertion loss, optical cable deterioration, etc. caused by interfacing various devices on the optical communication line. Compensation for losses caused by various environmental factors, such as losses, is appropriately compensated.

According to a fourth embodiment of a multiple ring structure wavelength division multiplexing passive optical network system according to the present invention, the signal compensator 500 includes a first 1 × 2 coupler 810 and a second 1 × 2 coupler. 820, an optical circulator 830, and a pair of amplifiers 840.

The first 1 × 2 coupler 810 is output from the multiplexer / demultiplexer 230 of the central base station 200 to branch and output the signal output through the optical coupler 400, and the optical coupler A signal transmitted to the multiplexer / demultiplexer 230 of the central base station 200 is received via 400.

The second 1 × 2 coupler 820 branches and outputs a signal transmitted to the optical communication line 100a or 100b and receives a signal transmitted from the optical communication line 100a or 100b.

The optical circulator 830 allows the signal input from the second 1 × 2 coupler 820 and the signal output to the second 1 × 2 coupler 820 to be transmitted and received through different paths.

The amplifier 840 is installed on two paths between the first 1 × 2 coupler 810 and the optical circulator 830 in opposite directions, and amplifies and compensates signals transmitted and received through the two paths.

That is, the fourth embodiment is implemented so that the optical signal reflected to the optical communication path 100 is not introduced by using one optical circulator 830, and one end of the first 1 × 2 coupler 810 is The other ends of the optocouplers 400 connected to the other end of the optical coupler 400 connected to the multiplexer / demultiplexer 230 of the central base station 200 are respectively connected to one side of the pair of amplifiers 840 installed in opposite directions.

The other port of the optical circulator 830 is connected to the other side of the pair of amplifiers 840 installed in opposite directions, and the other port of the optical circulator 830 is connected to one end of the second 1 × 2 coupler 820. Connected.

Two other branched ends of the second 1 × 2 coupler 820 are connected to the optical communication line 100a or 100b, respectively.

Accordingly, optical signals transmitted and received between the multiplexer / demultiplexer 230 and the optical communication line 100a or 100b of the central base station 200 are mutually transmitted by the first 1 × 2 coupler 810 and the optical circulator 830. Insertion loss, optical cable deterioration, etc., caused by interfacing various devices on the optical communication line due to the amplification of signals transmitted and received by a pair of amplifiers 840 which have different transmission paths and installed in opposite directions on the two transmission paths, respectively. The loss caused by various environmental factors such as the loss caused by the compensation is appropriately compensated.

According to a fifth embodiment of a multiple ring structure wavelength division multiplexing passive optical network system according to the present invention, the signal compensator 500 includes a first 1 × 2 coupler 910 and a pair of optical circulators 920a. 920b, a pair of second 1x2 couplers 930a and 930b, and amplifier pairs 940a and 940b.

The first 1 × 2 coupler 910 is output from the multiplexer / demultiplexer 230 of the central base station 200 to branch and output the signal output through the optical coupler 400, and the optical coupler A signal transmitted to the multiplexer / demultiplexer 230 of the central base station 200 is received via 400.

The pair of optical circulators 920a and 920b are installed at each branch side of the first 1 × 2 coupler 910 and branched from the first 1 × 2 coupler 910 and outputted therefrom. Each signal is transmitted and received through different paths.

The pair of second 1x2 couplers 930a and 930b respectively output signals transmitted to the optical communication line 100a or 100b, and branch the signals received from the optical communication line 100a or 100b, respectively. Output

The pair of amplifiers 940a and 940b are provided in opposite directions on two paths respectively formed between the pair of optical circulators 920a and 920b and the pair of second 1x2 couplers 930a and 930b. Each amplifier is provided to compensate for the amplification of signals transmitted and received through these two paths.

That is, the fifth embodiment is implemented by using a pair of optical circulators 920a and 920b to block the reflected optical signals flowing through the two paths branched from the optical communication path 100, respectively. One end of the 1 × 2 coupler 910 is connected to the other end of the optical coupler 400 connected to the multiplexer / demultiplexer 230 of the central base station 200, and the other end of each branch is a pair of optical circulators. It is connected to one side port of the (920a) (920b).

Each of the other ports of the pair of optical circulators 920a and 920b is connected to one side of the pair of amplifier pairs 940a and 940b installed in opposite directions.

One side of a pair of second 1x2 couplers 930a and 930b is connected to the other side of the pair of amplifier pairs 940a and 940b respectively installed in the opposite directions, and the pair of second 1x2 couplers ( Each of the other sides 930a and 930b is connected to the optical communication line 100a or 100b.

Therefore, the optical signals transmitted and received between the multiplexer / demultiplexer 230 of the central base station 200 and the optical communication line 100a or 100b are optically transmitted through two paths branched by the first 1 × 2 coupler 910. A signal is transmitted and received, each of which has different subordinate transmission paths by the pair of optical circulators 920a and 920b and the pair of second 1x2 couplers 930a and 930b, and the two transmissions. Signals transmitted and received by a pair of amplifier pairs 940a and 940b respectively installed in opposite directions on the path are amplified appropriately, and various losses such as insertion loss and optical cable deterioration caused by interfacing various devices on the optical communication line. The losses caused by environmental factors will be compensated for properly.

According to a sixth embodiment of a multiple ring structure wavelength division multiplexing passive optical network system according to the present invention, the signal compensator 500 includes a 1 × 2 coupler 1010 and a pair of first optical circulators 1020a. 1020b, a pair of second optical cyclers 1030a and 1030b, and an amplifier pair 1040a and 1040b.

The 1 × 2 coupler 1010 is output from the multiplexer / demultiplexer 230 of the central base station 200 to branch and output the signal output through the optical coupler 400, and the optical coupler 400 Receives a signal transmitted to the multiplexer / demultiplexer 230 of the central base station 200 via.

The pair of first optical circulators 1020a and 1020b are installed at each branch side of the 1 × 2 coupler 1010 to branch out from the 1 × 2 coupler 1010 and output a signal input thereto. Each transmits and receives a different path.

The pair of second optical cyclers 1030a and 1030b respectively output signals transmitted to the optical communication line 100a or 100b and signals received from the optical communication line 100a or 100b through different paths, respectively. .

The amplifier pairs 1040a and 1040b are installed in opposite directions on two paths respectively formed between the pair of first optical circulators 1020a and 1020b and the pair of second optical circulators 1030a and 1030b. A pair of amplifiers are provided, respectively, to amplify and compensate for signals transmitted and received through these two paths.

In other words, this sixth embodiment is implemented to block the reflected optical signals introduced through the two paths diverged from the optical communication path 100 using two pairs of optical circulators 1020a, 1020b, 1030a and 1030b. For example, one end of the 1 × 2 coupler 1010 is connected to the other end of the optical coupler 400 connected to the multiplexer / demultiplexer 230 of the central base station 200, and the other end of each branch is connected to a pair. It is connected to one port of the first optical circulator 1010a, 1020b.

Each of the other ports of the pair of optical circulators 1020a and 1020b is connected to one side of the pair of amplifier pairs 1040a and 1040b that are installed in opposite directions.

Two ports of one pair of second optical circulators 1030a and 1030b are respectively connected to the other side of the pair of amplifier pairs 1040a and 1040b installed in opposite directions, respectively, and the pair of second optical circulators 1030a One port on the other side of the 1030b is connected to the optical communication line 100a or 100b.

Accordingly, the optical signal transmitted and received between the multiplexer / demultiplexer 230 and the optical communication line 100a or 100b of the central base station 200 is transmitted and received by the optical signal through two paths branched by the 1 × 2 coupler 1010. Each of these paths has different subordinate transmission paths by the pair of first optical circulators 1020a and 1020b and the pair of second optical circulators 1030a and 1030b, and on both transmission paths. The signals transmitted and received by a pair of amplifier pairs 1040a and 1040b respectively installed in opposite directions to each other are appropriately amplified so that various environmental factors, such as insertion loss and optical cable deterioration, caused by interfacing various devices on the optical communication line. The losses caused by the factors are compensated appropriately.

On the other hand, the detailed description of the other components sufficiently described in the first patent application No. 2003-98904 and the first patent application No. 2004-24234 previously filed by the applicant of the present invention will not be described in the specification and drawings of the present invention However, this omitted configuration is in principle to follow the contents described in the above patent.

Therefore, by the above it is possible to achieve the object of the multi-ring structure wavelength division multiplexing passive optical network system according to the present invention presented above.

As described above, the multi-ring structured wavelength division multiplexing passive optical network system according to the present invention employs a plurality of ring-type optical communication lines in the wavelength division multiplexing passive optical network system, thereby using a same number of subscribers. At the same time, it has a useful effect of being able to adequately compensate for the losses caused by various environmental factors.

Although the present invention has been described with reference to the accompanying drawings, it will be apparent to those skilled in the art that various modifications may be made therein without departing from the scope of the invention, which is covered by the following claims.

Claims (7)

A ring optical communication line; A plurality of optical transmitters for generating optical signals having different wavelengths, an optical receiver for receiving an optical signal having the same wavelength as that of the optical transmitter paired with the optical transmitter and converting the optical signal into an electrical signal; A multiplexer / demultiplexer for multiplexing and outputting optical signals having different wavelengths to the optical communication line, and demultiplexing and outputting the multiplexed optical signal input through the optical communication line, and outputting the optical signal output from a designated optical transmitter A central base station including a plurality of optical circulators for outputting to a multiplexer / demultiplexer and outputting an optical signal demultiplexed from the multiplexer / demultiplexer to a designated optical receiver; An optical branch / combiner for dropping only a signal having a wavelength of a specific band among the optical signals transmitted through the optical communication line and outputting the signal to the subscriber device and outputting the optical signal transmitted from the subscriber device to the optical communication line; At least one local base station including an optical circulator for outputting an optical signal dropped through a combiner to an optical receiver of the subscriber device and outputting an optical signal input from the optical transmitter of the subscriber device to the optical branch / combiner; In a wavelength division multiplexing (WDM) passive optical network (PON) system comprising: The wavelength division multiplexing passive optical network system is: A plurality of ring-shaped optical communication lines; A plurality of signal compensators connected to each of the ring-shaped optical communication lines to compensate for signals transmitted and received during the multiplexing / demultiplexing periods of the optical communication line and the central base station; A signal output from each of the signal compensators and connected to the multiplexing / demultiplexing periods of each of the plurality of signal compensators and the central base station to branch the signal output from the multiplexer / demultiplexer to each of the signal compensators, or the signal output from each of the signal compensators An optical coupler outputting a to the multiplexer / demultiplexer; Passive optical network system of the multiple ring structure wavelength division multiplexing method comprising a. The method of claim 1, The signal compensation unit: A first optical circulator for transmitting a signal output from the multiplexer / demultiplexer of the central base station and a signal input to the multiplexer / demultiplexer of the central base station through different paths; A 1 × 2 coupler for branching and outputting a signal transmitted to the optical communication line, and receiving a signal transmitted from the optical communication line; A second optical circulator for allowing a signal input from the 1 × 2 coupler and a signal output to the 1 × 2 coupler to be transmitted and received through different paths; A pair of amplifiers provided in opposite directions on two paths of the first optical cycle and the second optical cycle, and amplifying and compensating for signals transmitted and received through the two optical paths; Passive optical network system of the multiple ring structure wavelength division multiplexing method comprising a. The method of claim 1, The signal compensation unit: An optical circulator for transmitting and receiving signals output from the multiplexer / demultiplexer of the central base station and signals input to the multiplexer / demultiplexer of the central base station through different paths; A 2x2 coupler for branching and outputting a signal transmitted to the optical communication line, and for branching and outputting a signal received from the optical communication line; A pair of amplifiers installed in two opposite directions on the two paths between the optical circulator and the 2x2 coupler to amplify and compensate signals transmitted and received through the two paths; Passive optical network system of the multiple ring structure wavelength division multiplexing method comprising a. The method of claim 1, The signal compensation unit: A 1 × 2 coupler for branching and outputting a signal output from the multiplexer / demultiplexer of the central base station and receiving a signal transmitted to the multiplexer / demultiplexer of the central base station; A 2x2 coupler for branching and outputting a signal transmitted to the optical communication line, and for branching and outputting a signal received from the optical communication line; A pair of amplifiers installed on two paths between the 1 × 2 coupler and the 2 × 2 coupler in opposite directions to amplify and compensate signals transmitted and received through the two paths; Passive optical network system of the multiple ring structure wavelength division multiplexing method comprising a. The method of claim 1, The signal compensation unit: A first 1x2 coupler for branching and outputting a signal output from the multiplexer / demultiplexer of the central base station and receiving a signal transmitted to the multiplexer / demultiplexer of the central base station; A second 1x2 coupler for branching and outputting a signal transmitted to the optical communication line, and receiving a signal transmitted from the optical communication line; An optical circulator for transmitting and receiving a signal input from the second 1 × 2 coupler and a signal output to the second 1 × 2 coupler through different paths; A pair of amplifiers provided in opposite directions on two paths of the first 1 × 2 coupler and the optical circulation period and amplifying and compensating a signal transmitted and received through the two paths; Passive optical network system of the multiple ring structure wavelength division multiplexing method comprising a. The method of claim 1, The signal compensation unit: A first 1x2 coupler for branching and outputting a signal output from the multiplexer / demultiplexer of the central base station and receiving a signal transmitted to the multiplexer / demultiplexer of the central base station; A pair of optical circulators installed at each branch side of the first 1x2 coupler to transmit and output signals outputted from the first 1x2 coupler and input thereto through different paths; A pair of second 1x2 couplers each outputting a signal transmitted to the optical communication line and branching and outputting a signal received from the optical communication line; A pair of amplifiers each provided in opposite directions on two paths formed between the pair of optical circulators and the pair of second 1 × 2 couplers, respectively, and an amplifier pair for amplifying and compensating for signals transmitted and received through the two paths ; Passive optical network system of wavelength division multiplexing multiplexing structure comprising a multiple ring structure. The method of claim 1, The signal compensation unit: A 1 × 2 coupler for branching and outputting a signal output from the multiplexer / demultiplexer of the central base station and receiving a signal transmitted to the multiplexer / demultiplexer of the central base station; A pair of first optical circulators installed at each branch side of the 1x2 coupler to transmit and output signals outputted from the 1x2 coupler and signals input thereto through different paths; A pair of second optical circulators respectively outputting signals transmitted to the optical communication line and signals received from the optical communication line through different paths; An amplifier configured to amplify and compensate signals transmitted and received through the two paths, each having a pair of amplifiers installed in opposite directions on two paths respectively formed in the pair of first optical cycles and the pair of second optical cycles Pairs; Passive optical network system of the multiple ring structure wavelength division multiplexing method comprising a.

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