Optical transceiver and method for automatically setting wavelength thereof

Abstract

To provide an optical transceiver and a method for automatically setting a wavelength thereof.SOLUTION: An optical transceiver includes: an optical receiver configured to receive an optical transmission signal including wavelength information from another optical transceiver through a multiplexer / demultiplexer connected thereto; and a controller configured to identify a reception wavelength for communication with the other optical transceiver and to determine a wavelength corresponding to the reception wavelength as a transmission wavelength for communication with the other optical transceiver, based on the wavelength information included in the optical transmission signal.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to an optical transceiver and a method for automatically setting a wavelength thereof. [Background technology]

[0002] Wavelength-division multiplexing (WDM) is a technology that allows multiple optical signals to be transmitted simultaneously through the same optical fiber. This is achieved by assigning each optical signal a different wavelength. At the transmitting end of a WDM-based optical communication system, multiple signals with different wavelengths are transmitted through the same optical fiber. At the receiving end of a WDM-based optical communication system, the optical signals are separated by wavelength. The advantage of a WDM system is that it uses optical fiber efficiently by allowing one optical fiber to carry multiple optical signals with different carrier wavelengths.

[0003] Generally, optical communication devices on the transmitting and receiving sides of a WDM-based optical communication system are located several kilometers apart. The optical communication devices on both sides are connected by a multiplexer / demultiplexer and an optical cable, and transmit and receive optical signals between them at remote locations. For this optical communication, an optical link must be established by setting the transmit wavelength and receive wavelength of each corresponding optical transceiver. However, it is very tedious and time-consuming for an administrator to visit each optical communication device installation site and set the wavelengths of the optical transceivers. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Korean Patent Publication No. 10-2017-0115878 Summary of the Invention [Problem to be solved by the invention]

[0005] In order to solve the above-mentioned problems, the present invention provides an optical transceiver and a method for automatically setting a wavelength, which can be performed without the visit of an administrator.

[0006] The technical problems that the technical idea of ​​the present invention aims to solve are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description. [Means for solving the problem]

[0007] According to one aspect of the present invention, an optical transceiver is disclosed that includes: an optical receiver that receives an optical transmission signal containing wavelength information from another optical transceiver through a coupled multiplexer / demultiplexer; and a controller that identifies a receiving wavelength for communication with the other optical transceiver based on the wavelength information contained in the optical transmission signal, and determines a wavelength corresponding to the receiving wavelength as a transmitting wavelength for communication with the other optical transceiver.

[0008] According to an exemplary embodiment, the controller determines the transmit wavelength to be a wavelength corresponding to the receive wavelength using a pre-stored look-up table.

[0009] According to an exemplary embodiment, the controller generates receiving wavelength information regarding the receiving wavelength and transmitting wavelength information regarding the transmitting wavelength, and the optical transceiver further includes a transmitter that generates and outputs an optical response signal including the receiving wavelength information and the transmitting wavelength information.

[0010] According to an exemplary embodiment, the transmitter generates the optical response signal by superimposing an optical signal corresponding to the received wavelength information and the transmitted wavelength information with an optical signal having a wavelength indicated by the transmitted wavelength information.

[0011] According to an exemplary embodiment, the optical signal corresponding to the receiving wavelength information and the transmitting wavelength information and the optical signal having a wavelength indicated by the transmitting wavelength information are optical signals of different channels.

[0012] According to an exemplary embodiment, the channel of the optical signal corresponding to the receiving wavelength information and the transmitting wavelength information is an Auxiliary Management and Control Channel (AMCC).

[0013] According to another aspect of the present invention, an optical communication system is disclosed, comprising: a first optical transceiver that sequentially generates a plurality of optical transmission signals, each of which includes wavelength information, and outputs the plurality of optical transmission signals to a first multiplexer / demultiplexer connected thereto; and a second optical transceiver that receives one of the plurality of optical transmission signals through a second multiplexer / demultiplexer connected to the first multiplexer / demultiplexer, identifies a receiving wavelength for communication with the first optical transceiver based on the wavelength information included in the one optical transmission signal, and determines a wavelength corresponding to the receiving wavelength as a transmitting wavelength for communication with the first optical transceiver.

[0014] According to an exemplary embodiment, the first optical transceiver generates each of the plurality of optical transmission signals by superimposing an optical signal corresponding to the wavelength information and an optical signal having a wavelength indicated by the wavelength information.

[0015] According to an exemplary embodiment, the second optical transceiver determines the transmit wavelength corresponding to the receive wavelength using a pre-stored look-up table.

[0016] According to an exemplary embodiment, the second optical transceiver generates an optical response signal including receiving wavelength information regarding the receiving wavelength and transmitting wavelength information regarding the transmitting wavelength, and outputs the optical response signal to the second multiplexer / demultiplexer.

[0017] According to an exemplary embodiment, the second optical transceiver generates the optical response signal by superimposing an optical signal corresponding to the receiving wavelength information and the transmitting wavelength information with an optical signal having a wavelength indicated by the transmitting wavelength information.

[0018] According to an exemplary embodiment, the optical signal corresponding to the receiving wavelength information and the transmitting wavelength information and the optical signal having a wavelength indicated by the transmitting wavelength information are optical signals of different channels.

[0019] According to an exemplary embodiment, the channel of the optical signal corresponding to the receiving wavelength information and the transmitting wavelength information is AMCC. [Effects of the Invention]

[0020] According to an embodiment of the present invention, the wavelength of the corresponding optical transceiver is automatically set without an administrator visit, thereby improving convenience and reducing wavelength-related installation and maintenance costs.

[0021] Furthermore, there is no compatibility issue with the optical communication device in which the optical transceiver is implemented, and optical transceivers made up of the same components can be used at both ends of the link, reducing system construction costs.

[0022] The effects obtained by the embodiments according to the technical concept of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the following description. [Brief explanation of the drawings]

[0023] [Figure 1] 1 is a schematic diagram of an optical communication system according to an embodiment of the present invention; [Figure 2] 2 is a block diagram showing in more detail the main parts of an optical transceiver in the optical communication system according to the embodiment of the present invention; FIG. [Figure 3] 1 is a diagram illustrating an exemplary optical communication system for explaining a method for automatically setting a wavelength of an optical transceiver according to an embodiment of the present invention; [Figure 4] 1 is a flowchart of an exemplary method for automatically configuring a wavelength of an optical transceiver. [Figure 5]FIG. 1 is an exemplary diagram of a lookup table according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0024] The technical concept of the present invention can be variously modified and can have various embodiments, and therefore, specific embodiments are illustrated in the drawings and will be described in detail. However, this is not intended to limit the technical concept of the present invention to the specific embodiments, and it should be understood that the technical concept of the present invention includes all modifications, equivalents, and alternatives that fall within the scope of the technical concept of the present invention.

[0025] In explaining the technical concept of the present invention, if a detailed description of the related prior art is deemed to unnecessarily obscure the gist of the present invention, the detailed description will be omitted. Furthermore, numbers (e.g., 1, 2, etc.) used in the description of this specification are merely identification symbols for distinguishing one component from another.

[0026] Furthermore, in this specification, when a component is referred to as being "coupled" or "connected" to another component, it should be understood that the component may be directly coupled or connected to the other component, but may also be coupled or connected via another component in between, unless otherwise specified to the contrary.

[0027] In addition, terms such as "module", "device" and "subsystem" used in this specification refer to a unit that processes at least one function or operation, and this may be embodied in hardware or software, such as a processor, microprocessor, microcontroller, CPU (Central Processing Unit), GPU (Graphics Processing Unit), APU (Accelerate Processor Unit), DSP (Drive Signal Processor), ASIC (Application Specific Integrated Circuit), FPGA (Field Programmable Gate Array), or a combination of hardware and software.

[0028] It should be understood that the division of components in this specification merely represents a division according to the main function of each component. That is, two or more components described below may be combined into one component, or one component may be divided into two or more components according to further subdivided functions. It goes without saying that each component described below may perform some or all of the functions of other components in addition to its own main function, and that some of the main functions of each component may be exclusively performed by other components.

[0029] Hereinafter, various embodiments according to the technical concept of the present invention will be described in detail.

[0030] FIG. 1 is a schematic diagram of an optical communication system according to an embodiment of the present invention, and FIG. 2 is a block diagram showing in more detail the main parts of an optical transceiver in the optical communication system according to an embodiment of the present invention.

[0031] 1, an optical communication system 10 according to an embodiment of the present invention includes a first optical communication device 110 including n first optical transceivers 1100-1 through 1100-n (where n is a natural number greater than or equal to 2), second optical communication devices 120-1 through 120-n each including at least one second optical transceiver, and a multiflex / demultiplexer / demultiplexer (hereinafter referred to as MUX / DEMUX) 130. The first optical communication device 110 and MUX / DEMUX 130 are connected via an optical cable 141, and the second optical communication devices 120-1 through 120-n and MUX / DEMUX 130 are connected via corresponding optical cables among optical cables 143-1 through 143-n. Depending on the implementation, a tree topology may be formed by connecting a plurality of sub-MUX / DEMUXs to the MUX / DEMUX 130 and connecting the second optical communication devices 120-1 to 120-n to the sub-MUXs.

[0032] In some embodiments, the optical communication system 10 constitutes an optical transmission network, which is a sub-network constituting a fronthaul segment of a radio access network architecture. In this case, the first optical communication device 110 is a transverse device on the digital unit (DU) or baseband unit (BBU) side of the central office. The second optical communication devices 120-1 to 120-n are remote units (RU) or remote radio heads (RRH). The MUX / DEMUX 130 is a remote node for splitting and combining optical signals transmitted and received between the first optical communication device 110 and the second optical communication devices 120-1 to 120-n. However, the present invention is not limited thereto, and the technical concept of the present invention may also be applied to midhaul and backhaul segments of the radio access network architecture.

[0033] In another embodiment, the optical communication system 10 is applied to an optical subscriber network. In this case, the first optical communication device 110 is an optical line terminal (OLT) at the central office. The second optical communication devices 120-1 through 120-n are any one of a remote terminal (RT), an optical network terminal (ONT), and an optical network unit (ONU) at the subscriber side. The MUX / DEMUX 130 is a remote node for splitting and combining optical signals transmitted and received between the first optical communication device 110 and the second optical communication devices 120-1 through 120-n.

[0034] In yet another embodiment, the optical communication system 10 is applied to a distributed antenna system (DAS) for eliminating shadow areas of a base station, in which case the first optical communication device 110 is a headend unit, and the second optical communication devices 120-1 through 120-n and / or the MUX / DEMUX 130 are extension units or remote units.

[0035] As described above, the optical communication system 10 according to the technical concept of the present invention can be applied to various WDM-based optical communication networks implemented by optical communication devices located at remote locations and transmitting and receiving optical signals through corresponding optical transceivers.

[0036] For ease of explanation, the following description will focus on an embodiment in which the first optical communication device 110 is a longitudinal device on the DU side and the second optical communication devices 120-1 to 120-n are RUs, assuming that the optical communication system 10 constitutes a fronthaul segment of the above-mentioned radio access network architecture.

[0037] The first optical communication device 110 generates optical signals within a band to be used when transmitting high-speed data input from the DU side, multiplexes the generated optical signals, and transmits them to the MUX / DEMUX 130 (downlink basis).The first optical communication device 110 also receives optical signals transmitted from the second optical communication devices 120-1 to 120-n through the MUX / DEMUX 130, performs predetermined signal processing on the received optical signals, and transmits them to the DU side (uplink basis).

[0038] The first optical communication device 110 includes a main controller (MCU) 111, a memory 113, n first optical transceivers 1100-1 to 1100-n, and a MUX / DEMUX 115. The MCU 111 is configured to control the overall operation of the first optical communication device 110. Depending on the embodiment, the MCU 111 may also control a wavelength setting operation for determining at what wavelength the n first optical transceivers 1100-1 to 1100-n (described below) will transmit and receive optical signals to and from second optical transceivers 1200-1 to 1200-n of the corresponding second optical communication devices 120-1 to 120-n.

[0039] The memory 113 is connected to the MCU 111 and stores various information and program commands required for the operation of the first optical communication device 110. For example, the memory 113 stores information regarding the wavelength of an optical signal assigned to the first optical communication device 110.

[0040] The first optical transceivers 1100-1 through 1100-n are wavelength-tunable optical transceivers. The first optical transceivers 1100-1 through 1100-n perform an automatic wavelength setting operation to set the transmission wavelength and the reception wavelength for optical communication with the second optical transceivers 1200-1 through 1200-n of the corresponding second optical communication devices 120-1 through 120-n. The first optical transceivers 1100-1 through 1100-n transmit optical signals to or receive optical signals from the MUX / DEMUX 115 using the wavelengths determined by the automatic wavelength setting operation.

[0041] Each of the first optical transceivers 1100-1 to 1100-n includes a first controller 1110, a first transmitter 1130, and a first receiver 1150. Since the functions and operations of the first optical transceivers 1100-1 to 1100-n are substantially equivalent, the following description will focus on the first optical transceiver 1100-1.

[0042] The first controller 1110 is connected to the MCU 111 by wire or wirelessly, and manages and controls the first optical transceiver 1100-1.

[0043] The first controller 1110 manages the control (control of wavelength setting, control of communication status monitoring, etc.) required for smooth transmission and reception of payload data between the first optical transceiver 1100-1 and its corresponding second optical transceiver, for example, the second optical transceiver 1200-1, and the transmission and reception of information required for this (hereinafter referred to as control management data). For example, the first controller 1110 controls and manages wavelength tuning control required for wavelength setting between the first optical transceiver 1100-1 and its corresponding second optical transceiver 1200-1, the transmission and reception of tuned optical signals, and the generation and transmission and reception of information regarding the wavelengths of transmitted and received optical signals.

[0044] Here, the first controller 1110 is a general term for a processor that performs various controls and processing to transmit low-speed control management data as an out-of-band optical signal through an Auxiliary Management and Control Channel along with high-speed payload data transmitted as an in-band optical signal, and / or a memory (e.g., 1111) in which firmware, etc. are stored.

[0045] The first controller 1110 transmits the control management data to the second optical transceiver 1200-1 using various methods. For example, the first controller 1110 may use baseband intensity modulation to simultaneously transmit the control management data and payload data to the second optical transceiver 1200-1. For example, the first controller 1110 may use RF pilot tone (RF pilot tone) to superimpose the control management data and payload data and transmit them to the second optical transceiver 1200-1.

[0046] Baseband intensity modulation is a technique in which control and management data is stacked on top of payload data, while RF pilot tone modulation is a technique in which ASK or FSK modulated control and management data is superimposed on payload data. The transmission speed of control and management data is different from that of payload data. For example, the frequency of control and management data is several kHz, while the frequency of payload data is several tens to several hundred MHz. Since the methods for transmitting and receiving control and management data, such as baseband intensity modulation and RF pilot tone modulation, are already publicly known technologies, detailed descriptions will be omitted here.

[0047] The first transmitter 1130 converts the input payload data and control management data into optical signals and then superimposes them. The first transmitter 1130 includes a Transmitter Optical Sub-Assemblies (TOSA) consisting of a laser diode, a laser diode driving circuit (LDD), a biasing circuit, etc. The payload data input to the first transmitter 1130 is input via the LDD.

[0048] The first receiver 1150 separates the input optical signal demultiplexed by the MUX / DEMUX 115 into payload data and control / management data and outputs them in the corresponding configurations. In particular, the first receiver 1150 outputs the control / management data to the first controller 1110. The first receiver 1150 includes a photodiode, a ROSA (Receiver Optical Sub-Assemblies) consisting of a TIA (Trans-Impedance Amplifier), a post-amplifier, etc.

[0049] The MUX / DEMUX 115 multiplexes optical signals output from the first transmitters 1130 of the first optical transceivers 1100-1 through 1100-n, transmits the multiplexed optical signals to an optical cable, and demultiplexes optical signals received through the optical cable. Depending on the embodiment, the MUX / DEMUX 115 may be a separate device that is distinct from the first optical communication device 110.

[0050] The n second optical communication devices 120-1 through 120-n receive optical signals transmitted from the first optical communication device 110 through the MUX / DEMUX 130, perform optical-to-electrical conversion on the received optical signals, and transmit the signals to users at the cell site after performing predetermined signal processing (downlink standard).The second optical communication devices 120-1 through 120-n then perform electrical-to-optical conversion on the signals received from the users to generate optical signals, and transmit the generated optical signals to the MUX / DEMUX 130 (uplink standard).

[0051] Each of the second optical communication devices 120-1 to 120-n includes a corresponding one of the n second optical transceivers 1200-1 to 1200-n. In addition to the optical transceivers, the second optical communication devices 120-1 to 120-n also include components for performing the signal processing described above, and detailed descriptions thereof will be omitted for the sake of simplicity.

[0052] Each of the second optical transceivers 1200-1 to 1200-n includes a second controller 1210, a second transmitter 1230, and a second receiver 1250. The functions and operations of the second optical transceivers 1200-1 to 1200-n are substantially equivalent, and therefore the following description will focus on the second optical transceiver 1200-1.

[0053] The second controller 1210 is configured to control the overall operation of the second optical transceiver 1200-1.

[0054] The second controller 1210, similar to the first controller 1110 described above, manages the control necessary for smooth transmission and reception of payload data between the second optical transceiver 1200-1 and its corresponding first optical transceiver 1100-1 (control such as wavelength setting, control such as communication status monitoring), and the transmission and reception of information necessary for this (hereinafter referred to as control management data).

[0055] For example, the second controller 1210 controls and manages wavelength tuning control required for wavelength setting between the second optical transceiver 1200-1 and the corresponding first optical transceiver 1100-1, the transmission and reception of tuned optical signals, and the generation and transmission and reception of information regarding the wavelengths of the optical signals being transmitted and received.

[0056] Here, the second controller 1210 is a general term for a processor that performs various controls and processes to transmit low-speed control management data as an out-of-band optical signal through an Auxiliary Management and Control Channel along with high-speed payload data transmitted as an in-band optical signal, and / or a memory (e.g., 1211) in which firmware, etc. are stored.

[0057] The second transmitter 1230 has a configuration corresponding to the first transmitter 1130 , and the second receiver 1250 has a configuration corresponding to the first receiver 1150 .

[0058] Optical signals corresponding to payload data and control management data are generated and multiplexed through the second transmitter 1230 and the MUX / DEMUX 130 and transmitted to the first optical transceiver 1100-1. Optical signals received from the first optical transceiver 1100-1 through the MUX / DEMUX 130 and the second receiver 1250 are demultiplexed and converted into electrical signals.

[0059] The above describes the configuration of each of the first and second optical transceivers and the general functions of each component. Hereinafter, the automatic wavelength setting operation between the corresponding first and second optical transceivers in the optical communication system 10 will be specifically described with reference to Figures 3 to 5.

[0060] Fig. 3 is a diagram schematically illustrating an exemplary optical communication system for explaining a method for automatically setting a wavelength of an optical transceiver according to an embodiment of the present invention, Fig. 4 is a flowchart of the exemplary method for automatically setting a wavelength of an optical transceiver, and Fig. 5 is an exemplary view of a lookup table according to an embodiment of the present invention. Fig. 3 is a schematic diagram of the optical communication system 10 shown in Fig. 1, focusing on the optical transceivers and MUX / DEMUX, and Fig. 4 illustrates the operation of the method for automatically setting a wavelength between, for example, the first optical transceiver 1100-1 and the second optical transceiver 1200-1 of the optical transceivers shown in Fig. 3.

[0061] First, referring to FIG. 3, n first optical transceivers 1100-1 to 1100-n are connected to the MUX / DEMUX 115, n second optical transceivers 1200-1 to 1200-n are connected to the MUX / DEMUX 130, and the MUX / DEMUXs 115 and 130 are connected via an optical cable 141.

[0062] The first and second optical transceivers 1100-1 to 1100-n and 1200-1 to 1200-n are wavelength-tunable optical transceivers, and therefore generate optical signals by changing the wavelength in a predetermined manner.

[0063] For example, the first optical transceivers 1100-1 to 1100-n generate optical signals having the first to nth wavelengths while changing the wavelength to the first to nth wavelengths under the control of the first controller 1110 depending on the wavelength assigned to the first optical communication device 110 in which the first optical transceiver 1100-1 is implemented.

[0064] The second optical transceivers 1200-1 through 1200-n generate optical signals having one of the first through n-th wavelengths according to the wavelengths assigned to the second optical communication devices 120-1 through 120-n in which the second optical transceiver 1200-1 is installed, under the control of the second controller 1210. In this case, the second controller 1210 analyzes the wavelength of the optical signal received from one of the first optical transceivers 1100-1 through 1100-n, and generates an optical signal having one of the first through n-th wavelengths corresponding to the wavelength of the received optical signal according to the analysis result. The operation of the second controller 1210 to select the wavelength of the optical signal will be described later with reference to FIGS. 4 and 5.

[0065] The first optical transceivers 1100-1 to 1100-n are connected to any port of the MUX / DEMUX 115. In Fig. 3, the first optical transceiver 1100-1 is connected to the first port Pc1, the first optical transceiver 1100-2 is connected to the second port Pc2, and the first optical transceiver 1100-n is connected to the n-th port Pcn.

[0066] The second optical transceivers 1200-1 to 1200-n are connected to any port of the MUX / DEMUX 130. In Fig. 3, the second optical transceiver 1200-1 is connected to the first port PR1, the second optical transceiver 1200-2 is connected to the second port PR2, and the second optical transceiver 1200-n is connected to the n-th port PRn.

[0067] Meanwhile, the MUX / DEMUX 115 is configured so that only optical signals of a predetermined wavelength are transmitted through each port via the optical cable. For example, the first port Pc1 is preset to transmit only optical signals of the first wavelength. In this case, the wavelengths preset for the second port Pc2 through the n-th port Pcn are all different. The same applies to the connected MUX / DEMUX 130.

[0068] Therefore, among the first and second optical transceivers 1100-1 through 1100-n and 1200-1 through 1200-n connected to the MUX / DEMUXs 115 and 130, corresponding optical transceivers must set wavelengths to communicate with each other using optical signals of wavelengths that can be transmitted or received through their connected ports. To this end, the first and second optical transceivers 1100-1 through 1100-n and 1200-1 through 1200-n according to an embodiment of the present invention automatically recognize optical signals of wavelengths corresponding to any of their connected ports and perform an automatic wavelength setting operation to set the wavelength for communication with the corresponding optical transceiver.

[0069] The steps described below are performed by one of the first optical transceivers 1100-1 through 1100-n and one of the second optical transceivers 1200-1 through 1200-n. The two optical transceivers performing the steps are optical transceivers that form an optical link connection and can transmit and receive optical signals to and from each other. The following description will be given assuming that the first optical transceiver 1100-1 and the second optical transceiver 1200-1 form an optical link connection to each other.

[0070] 4, in step S410, the first optical transceiver 1100-1 generates first through n-th optical transmission signals having first through n-th wavelengths and outputs them to the MUX / DEMUX 115. Here, the first through n-th optical transmission signals include transmission wavelength information regarding each wavelength (i.e., corresponding wavelength among the first through n-th wavelengths).

[0071] The first through nth wavelengths and corresponding transmission wavelength information are preset to perform an automatic wavelength setting operation, and the setting values ​​are stored in the memory 1111 of the first controller 1110. However, the present invention is not limited to this, and the setting values ​​may be stored in the memory 113 of the first optical communication device 110. Alternatively, the setting values ​​may be transmitted to the first controller 1110 via the MCU 111 from the MCU 111, an external management server (not shown), a local terminal, etc.

[0072] The transmission wavelength information is information about the length of a corresponding wavelength, and is information generated as control management data by the first controller 1110. For example, for a first optical transmission signal having a first wavelength, the first controller 1110 generates information about the length of the first wavelength as control management data.

[0073] The first transmitter 1130 generates optical signals (test optical signals) having first through n-th wavelengths, and generates optical signals (control management optical signals) corresponding to transmission wavelength information indicating the first through n-th wavelengths under the control of the first controller 1110. The first transmitter 1130 generates an optical transmission signal by sequentially superimposing the corresponding test optical signals and control management optical signals, and outputs the generated optical transmission signal to the MUX / DEMUX 115.

[0074] In step S420, the second optical transceiver 1200-1 receives only the m-th optical transmission signal from among the first through n-th optical transmission signals via the MUX / DEMUX 115, the optical cable 141, and the MUX / DEMUX .

[0075] As mentioned above, each port of MUX / DEMUX 115 functions as a BPF (Band Pass Filter) to output only optical signals of a predetermined wavelength, so that only one of the first to nth optical transmission signals transmitted through port Pc1 to which first optical transceiver 1100-1 is connected, for example, the mth (m is a natural number less than or equal to n) optical transmission signal, is transmitted to the second optical transceiver 1200-1 side through optical cable 141 and MUX / DEMUX 130.

[0076] In step S430, the second receiver 1250 of the second optical transceiver 1200-1 outputs the m-th transmission wavelength information included in the m-th optical transmission signal to the second controller 1210. The second controller 1210 analyzes the m-th transmission wavelength information to identify the m-th wavelength. That is, the second controller 1210 identifies the wavelength of the optical signal that the second optical transceiver 1200-1 can receive from the first optical transceiver 1100-1 as the m-th wavelength.

[0077] In step S440, the second optical transceiver 1200-1 identifies a transmission wavelength corresponding to the identified reception wavelength using a lookup table stored in the memory 1211. The lookup table is a table that pre-assigns corresponding reception wavelengths and transmission wavelengths, taking into account the wavelengths assigned to each MUX / DEMUX port, and can be updated according to the operating environment of the optical transceiver. Specifically, the second controller 1210 uses the lookup table to identify the transmission wavelength matched with the reception wavelength, the mth wavelength, as the pth wavelength. If the identified reception wavelength is the ath wavelength, the second controller 1210 may read the αth wavelength, which is the wavelength matched with the ath wavelength, as the transmission wavelength (see FIG. 5). Similarly, if the identified reception wavelength is the bth wavelength, the second controller 1210 may read the βth wavelength, which is the wavelength matched with the ath wavelength, as the transmission wavelength (see FIG. 5).

[0078] In step S450, the second optical transceiver 1200-1 generates an optical response signal having a pth wavelength in response to the mth optical transmission signal and outputs the optical response signal to the MUX / DEMUX 130. Here, the optical response signal includes transmission wavelength information regarding the pth wavelength and further includes reception wavelength information regarding the reception wavelength (e.g., the mth wavelength) of the second optical transceiver 1200-1 identified in step S430.

[0079] The transmission wavelength information is information about the length of a corresponding wavelength, and is information generated as control management data by the second controller 1210. For example, for an optical response signal having a p-th wavelength, the second controller 1210 generates information about the length of the p-th wavelength as control management data (e.g., AMCC (Auxiliary Management and Control Channel) data).

[0080] Furthermore, the receiving wavelength information is information about the length of the corresponding receiving wavelength, and is information generated as control management data by the second controller 1210. For example, when the receiving wavelength is the m-th wavelength, the second controller 1210 generates information about the length of the second wavelength as control management data (e.g., AMCC data).

[0081] In addition, the second transmitter 1230 generates an optical signal (test optical response signal) having the pth wavelength, and under the control of the second controller 1210, generates an optical signal (control management optical signal) corresponding to the transmitting wavelength information and / or receiving wavelength information, superimposes the generated test optical response signal and the control management optical signal to generate the optical response signal, and outputs the generated optical response signal to the MUX / DEMUX 130.

[0082] In step S460, the first optical transceiver 1100-1 receives the optical response signal through the MUX / DEMUX 130, the optical cable 141, and the MUX / DEMUX 115. Each port of the MUX / DEMUX 130 functions as a band-pass filter (BPF) to output only optical signals of a predetermined wavelength. Since the second optical transceiver 1200-1 has transmitted the optical response signal having a wavelength that can pass through the port PR1, the optical response signal is transmitted to the first optical transceiver 1100-1 through the MUX / DEMUX 115.

[0083] In step S470, the first receiver 1150 of the first optical transceiver 1100-1 outputs the transmitting wavelength information and the receiving wavelength information included in the optical response signal to the first controller 1110. The first controller 1110 analyzes the transmitting wavelength information and the receiving wavelength information and determines that the wavelength that the first optical transceiver 1100-1 can receive from the second optical transceiver 1200-1 is the pth wavelength and that the wavelength that the first optical transceiver 1100-1 can transmit to the second optical transceiver 1200-1 is the mth wavelength.

[0084] In step S480, the first controller 1110 generates optical link information between the first optical transceiver 1100-1 and the second optical transceiver 1200-1, including information about the identified transmit and receive wavelengths (i.e., the mth wavelength and pth wavelength). The first controller 1110 and the first transmitter 1130 generate an out-of-band optical signal corresponding to the generated optical link information (as control management data (e.g., AMCC data)) and transmit it to the second optical transceiver 1200-1 via the MUX / DEMUX 115, the optical cable 141, and the MUX / DEMUX 130. The second optical transceiver 1200-1 also recognizes that the wavelength setting operation has been completed upon receiving the optical link information.

[0085] Through the above-described operation, the first optical transceiver 1100-1 and the second optical transceiver 1200-1 automatically recognize and set the wavelengths that can be transmitted and received from each other, and perform optical communication.

[0086] As described above, in the optical communication system 10 according to one embodiment of the present invention, the wavelength-tunable optical transceivers on the transmitting and receiving sides automatically set the wavelengths for optical communication without the need for a manager to make any direct adjustments. This not only improves the convenience of installation and maintenance but also reduces costs.

[0087] Furthermore, the optical transceiver has versatility without compatibility issues with optical communication devices to which it is applied, and the wavelength-tunable optical transceivers on both sides can have substantially the same components, significantly reducing the system construction cost.

[0088] Although the present invention has been described above with reference to preferred embodiments, those skilled in the art will understand that the technical concept of the present invention can be modified and changed in various ways without departing from the technical concept and scope of the present invention as set forth in the claims below. [Explanation of symbols]

[0089] 10: Optical communication systems 110, 120: Optical communication device 1100, 1200: Optical transceiver

Claims

1. a receiver that receives optical transmission signals containing wavelength information from other optical transceivers through an associated multiplexer / demultiplexer; a controller that identifies a receiving wavelength for communication with the other optical transceiver based on the wavelength information included in the optical transmission signal, determines a wavelength corresponding to the receiving wavelength as a transmitting wavelength for communication with the other optical transceiver, and generates receiving wavelength information regarding the receiving wavelength and transmitting wavelength information regarding the transmitting wavelength; a transmitter that generates and outputs an optical response signal including the reception wavelength information and the transmission wavelength information, and generates the optical response signal by superimposing an optical signal corresponding to the reception wavelength information and the transmission wavelength information on an optical signal having a wavelength indicated by the transmission wavelength information; an optical transceiver, wherein the optical signal corresponding to the receiving wavelength information and the transmitting wavelength information and the optical signal having a wavelength designated by the transmitting wavelength information are optical signals of different channels;

2. 2. The optical transceiver according to claim 1, wherein the controller determines the wavelength corresponding to the receiving wavelength as the transmitting wavelength using a look-up table stored in advance.

3. 2. The optical transceiver of claim 1, wherein the channel of the optical signal corresponding to the receiving wavelength information and the transmitting wavelength information is an AMCC (Auxiliary Management and Control Channel).

4. a first optical transceiver for sequentially generating a plurality of optical transmission signals each including wavelength information and outputting the optical transmission signals to a first multiplexer / demultiplexer connected thereto; a second optical transceiver that receives one of the plurality of optical transmission signals through a second multiplexer / demultiplexer connected to the first multiplexer / demultiplexer, identifies a reception wavelength for communication with the first optical transceiver based on wavelength information included in the one optical transmission signal, and determines a wavelength corresponding to the reception wavelength as a transmission wavelength for communication with the first optical transceiver; the second optical transceiver generates an optical response signal including reception wavelength information regarding the reception wavelength and transmission wavelength information regarding the transmission wavelength, and outputs the optical response signal to the second multiplexer / demultiplexer; generating the optical response signal by superimposing an optical signal corresponding to the receiving wavelength information and the transmitting wavelength information on an optical signal having a wavelength indicated by the transmitting wavelength information; An optical communication system, characterized in that the optical signal corresponding to the receiving wavelength information and the transmitting wavelength information and the optical signal having a wavelength indicated by the transmitting wavelength information are optical signals of different channels.

5. 5. The optical communication system of claim 4, wherein the first optical transceiver generates each of the plurality of optical transmission signals by superimposing an optical signal corresponding to the wavelength information and an optical signal having a wavelength indicated by the wavelength information.

6. 5. The optical communication system according to claim 4, wherein the second optical transceiver determines the wavelength corresponding to the receiving wavelength as the transmitting wavelength using a look-up table stored in advance.

7. 5. The optical communication system of claim 4, wherein the channel of the optical signal corresponding to the receiving wavelength information and the transmitting wavelength information is an AMCC (Auxiliary Management and Control Channel).

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