JP2011146863A - Communication system, transmission device, and reception device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To transmit and receive information other than main information without using wavelength different from wavelength for transmitting the main information. <P>SOLUTION: A transmission node 10 is equipped with: a transmission information intensity modulation part 102 for modulating monitoring information showing the operation condition of any transmission node 10 on this communication system to intensity information by an intensity modulation method; and an optical amplifier part 106 for fluctuating the intensity of an optical signal of main information modulated by a modulation method in which the main information being an optical signal transmitted from the transmission node 10 to a reception node 20, does not depend on intensity, based on the intensity information modulated by the transmission information intensity modulation part 102, and outputting an optical signal with the fluctuated intensity. The reception node 20 is equipped with an intensity signal demodulation part 204 for demodulating the optical signal output by the optical amplifier part 106 of the transmission node 10 by an intensity demodulation method. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a communication system, a transmission device, and a reception device.

  In an OADM (Optical Add / Drop Multiplexer) device, device information and alarms of each node are sent to an NMS (Network Management System, network management system), and the NMS performs network monitoring and control. . In this case, in order to transmit the device information and alarm of each node to the NMS, it is necessary to construct a dedicated network for each node installation base or to prepare a separate line. In order to reduce the number of lines for device information and alarm transmission, there is a method in which device information and alarm information of a plurality of nodes are transmitted between the nodes, aggregated to a specific node, and the specific node transmits to the NMS.

  In order to reduce the number of lines for device information and alarm transmission, the method of aggregating device information and alarm information to a specific node and transmitting it to the NMS also transmits information of a node having only a function of amplifying light. It is necessary to prepare a dedicated laser for transmitting information having a wavelength different from that of the main information, and transmit alarm information between the OADM nodes. This wavelength is generally called OSC (Optical Supervision Channel).

  FIG. 10 is a diagram illustrating a configuration of a transmission node and a reception node using an information transmission dedicated laser having a wavelength different from that of the main information. A method in which the transmission node 50 transmits transmission information such as device information and an alarm to the reception node 60 will be described with reference to FIG.

  The transmission information reception unit 501 receives transmission information from the monitoring unit 700 and inputs the transmission information to the transmission information modulation unit 502. The transmission information modulation unit 502 modulates the transmission signal input from the transmission information reception unit 501. The laser diode 503 converts the transmission information modulated by the transmission information modulation unit 502 into an optical signal. The optical wavelength multiplexing unit 508 combines the optical signal converted by the laser diode 503 and the optical signal obtained by amplifying the optical signal multiplexed by the optical wavelength multiplexing unit 506 by the optical amplification unit 507. The transmission node 50 transmits the optical signal combined by the optical wavelength multiplexing unit 508 to the reception node 60.

  The optical signal demultiplexing unit 601 demultiplexes the optical signal converted by the laser diode 503 from the optical signal transmitted from the transmission node, and inputs the demultiplexed signal to the light receiving element 602. The light receiving element 602 converts the optical signal converted by the laser diode 503 into an electric signal and inputs the electric signal to the transmission information demodulating unit 603. The transmission information demodulator 603 demodulates the electric signal input from the light receiving element 602. The transmission information detection unit 604 receives the transmission information based on the signal demodulated by the transmission information demodulation unit 603.

  That is, the transmission node 50 converts the transmission information into an optical signal having a wavelength different from the wavelength of the optical signal transmitting the main information, and combines the optical signal transmitting the main information and the optical signal converted from the transmission information. To the receiving node 60. The reception node 60 demultiplexes the optical signal obtained by converting the transmission information from the transmitted optical signal and receives the transmission information.

JP-A-3-214936 Japanese Patent No. 3503615

  However, when the transmission node 50 transmits the transmission information such as the device information and the alarm to the reception node 60 by the above-described method, the wavelength for transmitting the main information to be originally transmitted the device information and the wavelength for alarm transmission. The laser diode 503, the optical wavelength multiplexing unit 508, and the optical signal demultiplexing unit 601 are necessary. Further, the optical wavelength multiplexing unit 508 and the optical signal demultiplexing unit 601 cause a transmission loss of an optical signal for transmitting main information that should be originally transmitted. Also, Patent Documents 1 and 2 have the same problem.

  An object of the present invention is to provide a communication system, a transmission device, and a reception device capable of transmitting / receiving information other than the main information without using a wavelength different from the wavelength for transmitting the main information.

  The present invention is a communication system including a transmission apparatus and a reception apparatus, and the transmission apparatus modulates monitoring information indicating an operation status of any of the transmission apparatuses on the communication system into intensity information by an intensity modulation method. The intensity modulation unit, and the intensity modulation unit modulates the intensity of the optical signal of the main information, which is modulated by a modulation method that does not depend on the intensity of the main information that is an optical signal transmitted from the transmission device to the reception device. An optical amplifying unit that varies based on the intensity information and outputs an optical signal with the intensity varied, and the receiving device performs intensity demodulation on the optical signal output by the optical amplifying unit of the transmitting device. A communication system comprising an intensity signal demodulator that demodulates according to a system.

  In addition, the present invention is a transmission device of a communication system including a transmission device and a reception device, wherein monitoring information indicating an operation status of any of the transmission devices on the communication system is modulated into intensity information by an intensity modulation method. The intensity modulation unit, and the intensity modulation unit modulates the intensity of the optical signal of the main information, which is modulated by a modulation method that does not depend on the intensity of the main information that is an optical signal transmitted from the transmission device to the reception device. An optical amplifying unit that varies based on the intensity information and outputs an optical signal in which the intensity is varied is provided.

  In addition, the present invention is a receiving device of a communication system including a transmitting device and a receiving device, wherein the monitoring information indicating the operation status of any of the transmitting devices on the communication system is modulated by an intensity modulation method. Intensity demodulation of an optical signal of main information, which is an optical signal whose intensity is changed based on information and is modulated by a modulation method in which main information is an optical signal transmitted from the transmitting apparatus to the receiving apparatus. A receiving apparatus comprising an intensity signal demodulating unit for demodulating by a method.

  Further, the present invention provides an optical signal distribution unit that distributes the optical signal of the main information in two, and the intensity of the optical signal of one of the main information among the optical signals of the main information distributed by the distribution unit. An optical amplifying unit that varies the intensity of the optical signal of the main information so as to be constant, and the intensity signal demodulating unit distributes the optical signal of the other main information distributed by the optical signal distribution unit, The receiving apparatus performs demodulation using the intensity demodulation method.

  According to the present invention, the intensity modulation unit of the transmission apparatus modulates monitoring information into intensity information by an intensity modulation method. In addition, the optical amplification unit of the transmission device varies the intensity of the optical signal of the main information, which is modulated by the modulation method whose main information does not depend on the intensity, based on the intensity information modulated by the intensity modulation unit. Output optical signal. The intensity signal demodulating unit of the receiving device demodulates the optical signal output from the optical amplifying unit of the transmitting device using an intensity demodulation method. Thereby, this invention can transmit / receive information other than main information, without using the wavelength different from the wavelength which transmits main information.

It is the schematic which showed the structure of the optical communication system in one Embodiment of this invention. It is the block diagram which showed the structure of the transmission node in this embodiment, and the structure of the receiving node. It is the graph which showed the output level of the optical signal which modulated the alarm monitoring information in this embodiment with an intensity modulation system. It is the graph which showed the output level and phase state of the optical signal which modulated the main information in this embodiment by the phase modulation system. In this embodiment, the alarm monitoring information is changed according to the output level of the optical signal modulated by the intensity modulation method, and the graph shows the output level and phase state of the optical signal modulated by the phase modulation method of the main information. is there. It is the graph which showed the phase and output level of the optical signal which the transmission node in this embodiment transmits alarm monitoring information and main information. It is the graph which showed the phase and output level of the optical signal which the transmission node in this embodiment transmits alarm monitoring information and main information. It is the flowchart which showed the operation | movement procedure with the transmission node and receiving node in this embodiment. It is the flowchart which showed the operation | movement procedure with the transmission node and receiving node in this embodiment. It is the schematic which showed the structure of the conventional transmission node, and the structure of the receiving node.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram illustrating a configuration of an optical communication system according to the present embodiment. In the illustrated example, the optical communication system includes nodes 1 to 4 and an OpS (Operation Systems) server 5. The nodes 1 to 4 are devices that relay optical signals that transmit / receive and relay main information. The main information is information transmitted from the transmission source nodes 1 to 4 to the transmission destination nodes 1 to 4.

  The node 3 transmits its own alarm monitoring information to the node 2 or the node 4. The alarm monitoring information (monitoring information) is monitoring information indicating the operation status (device state, alarm, etc.) of the nodes 1 to 4. Further, the nodes 2 and 4 transmit the alarm monitoring information of the own device and the alarm monitoring information of the node 3 to the node 1. Further, the node 1 transmits its own alarm monitoring information and the alarm monitoring information of the nodes 2 to 4 to the OpS server 5. The OpS server 5 is a device that receives the alarm monitoring information of the nodes 1 to 4 transmitted from the node 1 and centrally manages the operation status and failure occurrence of the nodes 1 to 4.

  Node 1 is connected to nodes 2 and 4 via optical fibers 101 and 105, and transmits data to nodes 2 and 4 using optical signals. Node 2 is connected to nodes 1 and 3 by optical fibers 108 and 102, and transmits data to nodes 1 and 3 using optical signals. Node 3 is connected to nodes 2 and 4 via optical fibers 107 and 103, and transmits data to nodes 2 and 4 using optical signals. The node 4 is connected to the nodes 1 and 3 through the optical fibers 104 and 106, and transmits data to the nodes 1 and 3 using an optical signal. Further, the node 1 and the OpS server 5 exchange information with each other by a DCN 6 (Data Communication Network).

  Next, the configuration of the nodes 1 to 4 will be described. Hereinafter, the nodes 1 to 4 that transmit the main information and the alarm monitoring information will be described as transmitting nodes, and the receiving nodes 1 to 4 will be described as receiving nodes. The nodes 1 to 4 have both transmission node and reception node configurations. For example, when node 1 transmits main information and alarm monitoring information to node 2, node 1 is a transmitting node and node 2 is a receiving node. When node 2 transmits main information and alarm monitoring information to node 1, node 2 is a transmitting node and node 1 is a receiving node.

  FIG. 2 is a block diagram showing the configuration of the transmission node 10 and the configuration of the reception node 20 in the present embodiment. In the illustrated example, the transmission node 10 includes a monitoring unit 300, a transmission information receiving unit 101, a transmission information intensity modulation unit 102, an amplification gain adjustment unit 103, an optical phase information transmission unit 104, and an optical wavelength multiplexing unit 105. And an optical amplifying unit 106.

  The monitoring unit 300 monitors and controls its own device. The transmission information receiving unit 101 adds information indicating start and end to the information transmitted to the receiving node 20. The transmission information intensity modulation unit 102 modulates information to be transmitted by an intensity modulation method. For example, as a method of converting the transmission signal into the intensity information, the transmission signal “1” is set as the strength signal “strong”, and the transmission signal “0” is set as the strength signal “weak”. The amplification gain adjustment unit 103 adjusts the gain of the optical amplification unit 106 based on the input intensity signal. For example, when the input intensity signal is “strong”, the amplification gain adjustment unit 103 adjusts the gain of the optical amplification unit 106 high. When the input intensity signal is “weak”, the amplification gain adjustment unit 103 adjusts the gain of the optical amplification unit 106 to be low. The optical phase information transmission unit 104 modulates main information to be transmitted to other nodes using a phase modulation method. The optical wavelength multiplexing unit 105 multiplexes optical signals having a plurality of types of wavelengths into one optical signal. The optical amplification unit 106 amplifies the intensity of the optical signal.

  The reception node 20 includes a monitoring unit 300, an optical signal distribution unit 201, a light receiving element 202, an intensity recognition unit 203, an intensity signal demodulation unit 204, a transmission information detection unit 205, an amplification gain adjustment unit 206, an optical An amplification unit 207, an optical wavelength separation unit 208, and an optical phase information reception unit 209 are provided.

  The optical signal distribution unit 201 distributes the optical signal transmitted from the transmission node 10 into two. The light receiving element 202 converts an optical signal into an electrical signal. The intensity recognition unit 203 recognizes the intensity of the optical signal. The intensity signal demodulator 204 demodulates the intensity signal into the transmitted information. The transmission information detection unit 205 detects the transmitted information. The amplification gain adjustment unit 206 adjusts the gain of the optical amplification unit 207. The optical amplification unit 207 amplifies the optical signal. The optical wavelength separation unit 208 separates the multiplexed optical signal for each of a plurality of types of wavelengths. The optical phase information receiving unit 209 receives information transmitted to its own device.

  Next, the alarm monitoring information modulation method according to this embodiment will be described. In the present embodiment, the transmission node 10 modulates the alarm monitoring information by the intensity modulation method and transmits the information to the reception node 20. That is, the transmission node 10 transmits alarm monitoring information (digital information) with the intensity of light. FIG. 3 is a graph showing the output level of an optical signal obtained by modulating the alarm monitoring information according to this embodiment by the intensity modulation method. In the figure, an example in which information is transmitted by the NRZ encoding method is shown, the horizontal axis indicates time, and the vertical axis indicates the output level. A signal with a high output level indicates a bit of “1”, and a signal with a low output level indicates a bit of “0”. The alarm monitoring information indicated by this graph is “1010”.

  Next, the main information modulation method in this embodiment will be described. In the present embodiment, the transmission node 10 modulates the main information by the phase modulation method and transmits it to the reception node 20. FIG. 4 is a graph showing an output level and a phase state of an optical signal obtained by modulating main information by the phase modulation method in the present embodiment. In the illustrated example, the horizontal axis indicates time, and the vertical axis indicates the output level. A signal having a phase state of “0” indicates a bit of “0”, and a signal having a phase state of “π” indicates a bit of “1”. The main information indicated by this graph is “010101101100”. The output level of the optical signal obtained by modulating the main information is constant. The modulation method for the main information is not limited to the phase modulation method, and any modulation method other than intensity modulation may be used.

  Next, a method for transmitting main information and alarm monitoring information in the present embodiment will be described. In this embodiment, since the main information is modulated by the phase modulation method (a modulation method other than the intensity modulation method), the information represented by the main information does not change even if the output level of the optical signal obtained by modulating the main information varies. . Therefore, in the present embodiment, the transmission node 10 transmits the alarm monitoring information by changing the output level of the optical signal obtained by modulating the main information. Thereby, the transmission node 10 can transmit the alarm monitoring information without using a wavelength different from the wavelength for transmitting the main information.

  FIG. 5 shows, in the present embodiment, the output level and phase state of an optical signal in which main information is modulated by a phase modulation method, in which alarm monitoring information is varied according to the output level of the optical signal modulated by an intensity modulation method. It is the shown graph. In the illustrated example, the horizontal axis indicates time, and the vertical axis indicates the output level. A signal having a phase state of “0” indicates a bit of “0”, and a signal having a phase state of “π” indicates a bit of “1”. The main information of this graph is “010101100”.

  Further, the output level of the optical signal modulated with the main information varies in accordance with the output level of the optical signal modulated with the alarm monitoring information. A signal in which the output level of the optical signal modulated with the main information is equal to or greater than the threshold value indicates “1”, and a signal in which the output level of the optical signal in which the main information is modulated is less than the threshold indicates “0”. The threshold value is a value that can determine the level of the output level of the optical signal obtained by modulating the main information, such as the average value (intermediate value) of the high value and the low value of the optical signal. The alarm monitoring information in the illustrated graph is “1010”. Note that the output level variation range of the optical signal modulated with the main information may be a range in which the level of the output level can be determined.

  Next, a specific example of alarm monitoring information will be described. In the present embodiment, the signal (start bit) indicating the start of the alarm monitoring information is “0101001”. A signal (end bit) indicating the end of the alarm monitoring information is “0011010”. In order for the receiving node 20 to identify whether the fluctuation in the output level of the optical signal transmitting the main information is a fluctuation obtained by intensity-modulating the alarm monitoring information or a fluctuation in the natural level, the transmitting node 10 Add a bit.

  6 and 7 are graphs showing the phase and output level of an optical signal in which the transmission node 10 according to this embodiment transmits alarm monitoring information and main information. In the illustrated example, the horizontal axis indicates time, and the vertical axis indicates the output level. A signal whose phase state is “0” indicates a bit of “0”, and a signal whose phase state is “π” indicates a bit of “1”. A signal whose output level is equal to or higher than the threshold indicates a bit of “1”, and a signal whose output level is lower than the threshold indicates a bit of “0”. In FIG. 6 and FIG. 7, the code | symbol (a) has shown main information, and the code | symbol (b) has shown alarm monitoring information.

  In the example shown in FIG. 6, every time 3 bits of main information is transmitted, 1 bit of alarm monitoring information is transmitted. However, since the information is independent, it is not necessary to synchronize. For example, as shown in FIG. 7, the timing at which the main information is transmitted may be different from the timing at which the alarm monitoring information is transmitted.

  4 to 7 exemplify a case where the optical signal obtained by modulating the main information has one wavelength, but in practice, an optical signal obtained by modulating the main information by a method other than the intensity modulation method is wavelength-multiplexed.

  Next, a method for transmitting main information and alarm monitoring information between the nodes 1 to 4 in this embodiment will be described. FIG. 8 and FIG. 9 are flowcharts showing operation procedures of the transmission node 10 and the reception node 20 in the present embodiment. The processes in steps S101 to S109 and the processes in steps S122 to S126 are processes performed by the transmission node 10. Further, the processes in steps S110 to S121 are processes performed by the receiving node 20.

(Step S <b> 101) Each unit included in the transmission node 10 inputs alarm monitoring information including its own failure state and control information to the monitoring unit 300. Thereafter, the process proceeds to step S102.
(Step S102) The monitoring unit 300 of the transmission node 10 stores the alarm monitoring information input from each unit included in the transmission node 10 in the storage unit. In addition, the monitoring unit 300 monitors the operation status of the own device based on the input alarm monitoring information. Thereafter, the process proceeds to step S103.

  (Step S103) The monitoring unit 300 of the transmission node 10 extracts the alarm monitoring information to be transmitted to the reception node 20 from the alarm monitoring information stored in the storage unit in Step S102. Thereafter, the process proceeds to step S104. As an extracting method, for example, a condition for transmitting to the receiving node 20 is determined in advance, and alarm monitoring information that matches the condition is extracted as alarm monitoring information to be transmitted to the receiving node 20. Note that any method may be used for extracting the alarm monitoring information to be transmitted to the receiving node 20.

  (Step S104) The monitoring unit 300 of the transmission node 10 monitors whether or not the number of wavelengths for transmitting main information increases or decreases. When the number of wavelengths for transmitting main information does not increase or decrease, the monitoring unit 300 inputs the alarm monitoring information extracted in step S103 to the transmission information receiving unit 101. When the number of wavelengths for transmitting main information increases or decreases, the monitoring unit 300 waits for a predetermined time (X seconds) until the number of wavelengths for transmitting main information increases or decreases. The alarm monitoring information extracted in S103 is input. Thereafter, the process proceeds to step S105. The OADM system has a mechanism for adjusting the output level of the entire optical signal in accordance with the number of wavelengths. Therefore, the output level of the optical signal that transmits the main information varies according to the number of wavelengths. Therefore, it waits until the output level of the optical signal for transmitting the main information becomes constant.

(Step S105) The transmission information reception unit 101 of the transmission node 10 adds a start bit and an end bit to the input alarm monitoring information. Thereafter, the process proceeds to step S106.
(Step S106) The transmission information receiving unit 101 of the transmission node 10 converts the alarm monitoring information to which the signal indicating the start of the alarm monitoring information and the signal indicating the end of the alarm monitoring information are added to a digital signal in Step S105. The transmission information receiving unit 101 inputs a digital signal to the transmission information intensity modulation unit 102. Thereafter, the process proceeds to step S107.

  (Step S <b> 107) The transmission information intensity modulation unit 102 of the transmission node 10 modulates the digital signal input in step S <b> 106 to convert it into intensity information, and inputs the intensity information to the amplification gain adjustment unit 103. Thereafter, the process proceeds to step S108.

  (Step S108) The amplification gain adjustment unit 103 of the transmission node 10 adjusts the gain of the optical amplification unit 106 based on the input intensity signal. Thereafter, the process proceeds to step S109.

  (Step S109) The optical amplifying unit 106 of the transmitting node 10 changes the intensity of the optical signal obtained by modulating the main information multiplexed according to the wavelength based on the adjustment of the amplification gain adjusting unit 103, and this optical signal is changed to the receiving node 20 Send to. At this time, the optical signal transmitted by the optical amplifying unit 106 is, for example, the signal illustrated in FIGS. Thereafter, the process proceeds to step S110.

  (Step S110) The optical signal distribution unit 201 of the reception node 20 receives the optical signal received from the optical amplification unit 106 of the transmission node 10 as “an optical signal for receiving main information” and “alarm monitoring information”. For optical signal ". Further, the optical signal distribution unit 201 inputs “an optical signal for receiving main information” to the light receiving element 202, and inputs an “optical signal for receiving alarm monitoring information” to the optical amplification unit 207. Then, the process of step S111 and step S113 is performed. The “optical signal for receiving main information” and the “optical signal for receiving alarm monitoring information” are signals obtained by simply dividing the optical signal received from the optical amplifying unit 106 of the transmission node 10 into two. Yes, it is an optical signal containing the same information.

(Step S111) The optical amplifying unit 207 of the receiving node 20 receives “an optical signal for receiving main information”. Thereafter, the process proceeds to step S112.
(Step S112) The optical amplifying unit 207 of the receiving node 20 amplifies the received “optical signal for receiving main information” and the amplified “optical signal for receiving main information” in the optical wavelength demultiplexing unit 208. To enter. At this time, the amplification gain adjustment unit 206 adjusts the gain of the optical amplification unit 207 so that the fluctuation / intensity of the output signal intensity becomes constant, and makes the intensity of the optical signal changed by the transmission node constant. Thereby, the alarm monitoring information transmitted from the transmission node 10 due to the strength of the optical signal can be deleted. In addition, the optical signal whose intensity is adjusted to be constant is processed in the same manner as the conventional processing. Specifically, the optical signal whose intensity is adjusted to be constant is separated for each wavelength by the optical wavelength separation unit 208. Of the optical signals separated for each wavelength, the optical signal of the wavelength transmitted to the receiving node 20 is input to the optical phase information receiving unit 209, and the optical signals of other wavelengths are input to the optical wavelength multiplexing unit. The

(Step S113) The light receiving element 201 of the receiving node 20 receives “an optical signal for receiving alarm monitoring information”. If it can be received, the process proceeds to step S114. If it cannot be received, the process proceeds to step S122.
(Step S <b> 114) The light receiving element 201 of the reception node 20 converts the intensity information of “the optical signal for receiving the alarm monitoring information” into an electric signal and inputs the electric signal to the intensity recognition unit 203 and the intensity signal demodulation unit 204. Then, the process of step S115 and step S116 is performed.

(Step S115) The strength recognition unit 203 of the reception node 20 recognizes the strength of the electric signal. The intensity of the electrical signal recognized by the intensity recognition unit 203 indicates the intensity of the optical signal amplified by the optical amplification unit 106 of the transmission node 10.
(Step S116) An electric signal indicating the intensity information of “optical signal for receiving alarm monitoring information” is input to the intensity signal demodulator 204 of the receiving node 20. If the electric signal indicating the intensity information of “the optical signal for receiving the alarm monitoring information” is input to the intensity signal demodulator 204, the process proceeds to step S117. If not, the process proceeds to step S122. move on.

(Step S117) The intensity signal demodulator 204 of the reception node 20 demodulates the electrical signal indicating the intensity information of “the optical signal for receiving the alarm monitoring information” into digital information, and inputs the digital information to the transmission information detector 205. Step S118) Digital information obtained by demodulating the electrical signal indicating the intensity information of the “optical signal for receiving the alarm monitoring information” is input to the transmission information detecting unit 205 of the receiving node 20. If digital information is input to the transmission information detection unit 205, the process proceeds to step S119. If not, the process proceeds to step S122.

(Step S119) The transmission information detection unit 205 of the reception node 20 extracts alarm monitoring information from the digital signal and inputs it to the monitoring unit. Thereafter, the process proceeds to step S120.
(Step S120) The monitoring unit 300 of the receiving node 20 recognizes the information of the transmitting node 10 based on the input alarm monitoring information. Thereafter, the process proceeds to step S121.

  (Step S121) The monitoring unit 300 of the reception node 20 transmits reception completion information notifying that the alarm monitoring information has been received to the transmission node 10. Thereafter, the process proceeds to step S122. Note that any method may be used for transmitting the reception completion information from the monitoring unit 300 of the reception node 20 to the transmission node 10. For example, as shown in FIG. 1, since an optical fiber for transmitting data and an optical fiber for receiving data are provided between the nodes, the monitoring unit 300 of the receiving node 20 The reception completion information is transmitted to the transmission node 10 by a communication method that uses an optical fiber for transmitting.

  (Step S122) The monitoring unit 300 of the transmission node 10 determines whether or not the reception completion information is received from the reception node 20 within a predetermined time (within y seconds) after transmitting the alarm monitoring information to the reception node 20. To do. When the monitoring unit 300 of the transmitting node 10 receives the alarm monitoring information from the receiving node 20 within a predetermined time after transmitting the alarm monitoring information to the receiving node 20, the monitoring unit 300 completes the process normally and does not receive the information. The process proceeds to step S123.

(Step S123) After transmitting the alarm monitoring information to the receiving node 20, the monitoring unit 300 of the transmitting node 10 waits for processing until a predetermined time (y seconds) elapses. After a predetermined time has elapsed, the process proceeds to step S124.
(Step S124) The monitoring unit 300 of the transmission node 10 counts (increases by one) the number of times the alarm monitoring information has been transmitted. Thereafter, the process proceeds to step S125.

  (Step S125) The monitoring unit 300 of the transmission node 10 determines whether or not the number of transmissions of the alarm monitoring information is equal to or greater than a predetermined number (z times). The monitoring unit 300 of the transmission node 10 proceeds to the process of step S126 when determining that the number of times of transmission of the alarm monitoring information is equal to or greater than the predetermined number of times, and proceeds to the process of step S104 when determining that the number is less than the predetermined number. Return to. Note that the monitoring unit 300 of the transmission node 10 transmits the alarm monitoring information to the reception node 20 again by returning to the process of step S104 and executing the process after step S104 again.

  (Step S126) The monitoring unit 300 of the transmission node 10 transmits information indicating that the alarm monitoring information cannot be transmitted to the reception node 20 to another node that transmits data to the transmission node 10. Thereafter, the maintenance person recognizes the above and ends the process.

  As described above, in this embodiment, an optical signal having a wavelength for transmitting main information (an optical signal having a wavelength for main information transmission) is modulated by a method other than the intensity modulation method (for example, a phase modulation method). Since it is a signal, the change in the output level of the optical signal does not depend on the main information. Therefore, the transmission information intensity modulation unit 102 of the transmission node 10 modulates the alarm monitoring information by the intensity modulation method, and the amplification gain adjustment unit 103 performs main information transmission based on the intensity information modulated by the transmission information intensity modulation unit 102. The alarm monitoring information is transmitted to the receiving node 20 by changing the output level of the optical signal of the wavelength for use.

  Further, the optical signal distribution unit 201 of the reception node 20 receives the received optical signal of the main information transmission wavelength as “an optical signal for receiving main information” and “an optical signal for receiving alarm monitoring information”. To distribute. Then, the light receiving element 201 of the receiving node 20 converts the intensity information of “the optical signal for receiving the alarm monitoring information” into an electric signal, and the intensity signal demodulating unit 204 demodulates the electric signal into the alarm monitoring information. This eliminates the need for an optical signal having a wavelength for transmitting alarm monitoring information (an optical signal having a wavelength for transmitting alarm monitoring information).

  Therefore, a laser diode that generates an optical signal having a wavelength for transmitting alarm monitoring information is not required as a constituent element of the transmission node 10, so that power saving can be realized. In addition, as a component of the transmission node 10, an optical wavelength combining unit that combines an optical signal having a wavelength for alarm monitoring information transmission with an optical signal having a wavelength for main information transmission is not necessary. Loss of the signal is reduced, the quality is improved, and the optical signal having the main information transmission wavelength can be transmitted over a long distance. Further, as a constituent element of the receiving node 20, a light receiving element for converting an optical signal having a wavelength for transmitting alarm monitoring information into an electric signal is not required, so that power saving can be realized. Further, as a component of the receiving node 20, an optical signal demultiplexing unit that demultiplexes the optical signal of the alarm monitoring information transmission wavelength and the optical signal of the main information transmission wavelength is not necessary. Loss of the optical signal is reduced to improve the quality, and the optical signal having the main information transmission wavelength can be transmitted over a long distance.

  In addition, the whole or a part of the functions of each unit constituting each device included in the optical communication system in the above-described embodiment is recorded on a computer-readable recording medium and a program for realizing these functions is recorded. You may implement | achieve by making a computer system read the program recorded on the medium and executing it. Here, the “computer system” includes an OS and hardware such as peripheral devices.

  The “computer-readable recording medium” refers to a portable medium such as a flexible disk, a magneto-optical disk, a ROM, and a CD-ROM, and a storage unit such as a hard disk built in the computer system. Further, the “computer-readable recording medium” dynamically holds a program for a short time, like a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line. It is also possible to include those that hold a program for a certain time, such as a volatile memory inside a computer system serving as a server or client in that case. The program may be a program for realizing a part of the functions described above, and may be a program capable of realizing the functions described above in combination with a program already recorded in a computer system.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and includes designs and the like that do not depart from the gist of the present invention. For example, although the present embodiment has been described using an example in which alarm monitoring information is transmitted and received, other information may be transmitted and received.

  1-4 ... nodes, 5 ... OpS server, 6 ... DCN, 10 ... sending node, 20 ... receiving node, 101 ... transmission information receiving unit, 102 ... transmission information Intensity modulation unit, 103 ... amplification gain adjustment unit, 104 ... optical phase information transmission unit, 105 ... optical wavelength multiplexing unit, 106 ... optical amplification unit, 201 ... optical signal distribution unit, 202・ ・ ・ Light receiving element, 203 ... Intensity recognition unit, 204 ... Intensity signal demodulation unit, 205 ... Transmission information detection unit, 206 ... Amplification gain adjustment unit, 207 ... Optical amplification unit, 208 ... Optical wavelength separation unit, 209 ... Optical phase information receiving unit, 300 ... Monitoring unit

Claims (4)

A communication system comprising a transmission device and a reception device,
The transmitter is
An intensity modulation unit that modulates monitoring information indicating an operation status of any of the transmission apparatuses on the communication system into intensity information by an intensity modulation method;
Based on the intensity information modulated by the intensity modulation unit, the intensity of the optical signal of the main information modulated by the modulation method independent of intensity of the main information that is an optical signal transmitted from the transmitting apparatus to the receiving apparatus. An optical amplifying unit that outputs an optical signal that is varied and the intensity is varied;
With
The receiving device is:
A communication system, comprising: an intensity signal demodulating unit that demodulates the optical signal output from the optical amplifying unit of the transmission apparatus by an intensity demodulation method. A transmission device of a communication system including a transmission device and a reception device,
An intensity modulation unit that modulates monitoring information indicating an operation status of any of the transmission apparatuses on the communication system into intensity information by an intensity modulation method;
Based on the intensity information modulated by the intensity modulation unit, the intensity of the optical signal of the main information modulated by the modulation method independent of intensity of the main information that is an optical signal transmitted from the transmitting apparatus to the receiving apparatus. An optical amplifying unit that outputs an optical signal that is varied and the intensity is varied;
A transmission device comprising: A receiving device of a communication system comprising a transmitting device and a receiving device,
The monitoring information indicating the operation status of any of the transmission apparatuses on the communication system is an optical signal whose intensity is changed based on the intensity information modulated by the intensity modulation method, and is transmitted from the transmission apparatus to the reception apparatus. A receiving apparatus comprising: an intensity signal demodulating unit that demodulates an optical signal of main information obtained by modulating main information, which is an optical signal, by a modulation method independent of intensity, using an intensity demodulation method. An optical signal distributor for distributing the optical signal of the main information into two;
An optical amplifying unit that varies the intensity of the optical signal of the main information so that the intensity of the optical signal of the main information of one of the optical signals of the main information distributed by the distributing unit is constant;
With
The receiving apparatus according to claim 3, wherein the intensity signal demodulating unit demodulates the other optical signal of the main information distributed by the optical signal distributing unit by the intensity demodulating method.

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