JP5042981B2 - Correction apparatus, wavelength division multiplexing optical transmission apparatus, and correction method - Google Patents

Description

  The present invention relates to a technique for adjusting the light intensity (output intensity) of an optical signal to be transmitted, and particularly to a technique for correcting a detected value of light intensity used for the adjustment.

  With recent advances in optical wavelength multiplexing technology, optical networks capable of high-speed and large-capacity data transmission are rapidly spreading. By using an optical wavelength multiplexing technique to multiplex and transmit optical signals of a plurality of different wavelengths (bands) on a single optical fiber cable, it is possible to transmit an information amount several to several thousand times over the same cable.

  However, the optical signal of each wavelength (band) may vary in light intensity (optical power level) during the transmission process. Therefore, in a general multiplexed optical transmission apparatus that performs optical transmission using optical wavelength multiplexing technology, a function for adjusting the light intensity for each wavelength (band) (hereinafter referred to as “light intensity adjustment function”) Some are provided.

  For example, Patent Document 1 describes an optical transmission device having a light intensity adjustment function. In Patent Document 1, the light intensity of each optical signal demultiplexed for each wavelength (band) is detected, and the light intensity for output is adjusted based on the detected value. Thereby, the optical intensity of each optical signal for each wavelength (band) can be adjusted to a constant value.

JP-A-2004-7058

  However, since the light intensity of each optical signal is adjusted based on the detection value, if there is an error in the detection value, the light intensity of each optical signal cannot be adjusted appropriately. For example, when a phenomenon occurs in which another optical signal leaks with respect to an optical signal whose light intensity is adjusted (hereinafter referred to as “crosstalk”) in the optical transmission device, an error occurs in the detected value. As a result, the light intensity of each optical signal cannot be adjusted to a constant value.

  An object of the present invention is to provide a technique for appropriately adjusting light intensity even when crosstalk occurs inside an apparatus having a light intensity adjusting function.

  In order to solve the above-described problem, the present invention calculates a noise component (crosstalk component leaked into an optical signal) added to an optical signal for adjusting the optical intensity, and calculates the noise component from a detected value detected for the optical intensity. (Crosstalk component) is removed, and the light intensity is adjusted using the correction value after removal.

  For example, the present invention provides a demultiplexing unit that demultiplexes an input wavelength-multiplexed optical signal for each wavelength, a detection unit that detects light intensity of each optical signal demultiplexed by the demultiplexing unit, and the detection An adjustment unit that adjusts the output intensity of each optical signal based on the light intensity detected by the unit, a multiplexing unit that combines and outputs each optical signal of the output intensity adjusted by the adjustment unit, And a noise component calculation unit that calculates a noise component added to each optical signal, and the noise component calculation unit calculates the light intensity detected by the detection unit. A noise removing unit that removes the noise component, and the adjusting unit adjusts the output intensity of each optical signal based on the light intensity from which the noise component has been removed by the noise removing unit.

  According to the present invention, even when crosstalk occurs inside an apparatus having a light intensity adjustment function, the light intensity can be adjusted appropriately.

(First embodiment)
Hereinafter, an example of an embodiment of the present invention will be described with reference to the drawings.

  An optical transmission apparatus 100 to which an embodiment of the present invention is applied is an apparatus that multiplexes and transmits optical signals of a plurality of different wavelengths (bands). The optical transmission device 100 has a “light intensity adjustment function” that adjusts the light intensity of an optical signal to be transmitted for each wavelength (band).

  FIG. 1 is a schematic configuration diagram of an optical transmission apparatus 100 to which the first embodiment of the present invention is applied. As shown in the figure, the optical transmission device 100 includes a wavelength demultiplexer 10a, a wavelength multiplexer 11, n (an integer greater than or equal to 2) optical variable attenuators 12 (1 to n), and n controls. A circuit 13 (1 to n), n optical couplers 14 (1 to n), n monitor units 15 (1 to n), and a correction device 16 are provided.

  The wavelength demultiplexer 10a demultiplexes the wavelength multiplexed optical signal input to the optical transmission device 100 into a single wavelength optical signal for each of a plurality (n) of different wavelengths (bands).

  The wavelength multiplexer 11 multiplexes a plurality (n) of single wavelength optical signals demultiplexed for each wavelength (band) by the wavelength demultiplexer 10a into the wavelength multiplexed optical signal. Then, the wavelength multiplexer 11 outputs the multiplexed wavelength multiplexed optical signal.

  For example, the wavelength demultiplexer 10 a and the wavelength multiplexer 11 are realized by a PLC-AWG (Planner Light Wave Circuit-Arrayed Waveguide Grating) type filter.

  A plurality (n) of optical transmission lines are installed in parallel between the wavelength demultiplexer 10a and the wavelength multiplexer 11, and each wavelength (band) demultiplexed by the wavelength demultiplexer 10a is provided. The single wavelength optical signal reaches the wavelength multiplexer 11 via each optical transmission line.

  Moreover, the optical variable attenuators 12 (1 to n) and the optical couplers 14 (1 to n) are arranged in each optical transmission line. As shown in the figure, in each optical transmission line, the optical variable attenuators 12 (1 to n) are installed on the wavelength demultiplexer 10a side, and the optical couplers 14 (1 to n) are installed on the wavelength multiplexer 11 side. The However, both arrangement locations are interchanged so that the optical variable attenuator 12 (1 to n) is installed on the wavelength multiplexer 11 side and the optical coupler 14 (1 to n) is installed on the wavelength demultiplexer 10 a side. May be.

  The optical variable attenuator 12 (1 to n) adjusts the light intensity of the optical signal to be output (the optical signal propagating through the optical transmission path). Specifically, the optical variable attenuator 12 (1 to n) controls to attenuate the light intensity of the optical signal propagating through the optical transmission line in accordance with a control signal supplied from a control circuit 13 (1 to n) described later. I do. For example, the optical variable attenuator 12 (1 to n) is realized by a VOA (Variable Optical Attenuator) or the like.

  In addition, the optical variable attenuator 12 (1 to n) can block and recover the optical signal propagating through the optical transmission line. In this case, the optical variable attenuator 12 (1 to n) is realized by, for example, a mechanical optical switch such as a 1 × 1 optical switch or a 2 × 1 optical switch, or a wave guide type optical switch based on SiO 2 or LiNbO 3. May be.

  The optical couplers 14 (1 to n) branch an optical signal propagating through the optical transmission line. Specifically, the optical coupler 14 (1 to n) supplies an optical signal propagating through the optical transmission line to a main signal supplied to the wavelength multiplexer 11 and a monitor unit 15 (1 to n) described later. Branches to the sub signal. Here, the distribution ratio of the main signal and the sub signal is, for example, 9: 1.

  The monitor unit 15 (1 to n) detects the light intensity of the optical signal propagating through the optical transmission line. Specifically, the monitor units 15 (1 to n) detect the light intensity of the sub-signals branched and input by the optical couplers 14 (1 to n). Then, based on the detected light intensity of the sub signal, data indicating the light intensity of the optical signal (for example, the optical signal output from the optical variable attenuator 12 (1 to n)) propagating through the optical transmission line (detection value data: P1 to Pn) and transmitted to the correction device 16.

  Here, the optical signal (sub signal) input to the monitor unit 15 (1 to n) includes a noise component, and the detection value data (P1 to Pn) generated by the monitor unit 15 (1 to n). ) Is a value including a noise component. As described above, the main factor for adding noise to the optical signals (sub-signals) input to the monitor units 15 (1 to n) is the crosstalk generated in the optical transmission apparatus 100 as described above. More specifically, there is crosstalk that occurs in the section from the downstream of the wavelength demultiplexer 10a to the monitor unit 15 (1 to n), as shown by the thick dotted line (first cross-roke A) in FIG. . This section includes, for example, crosstalk between optical transmission lines, crosstalk between optical variable attenuators 12 (1 to n), crosstalk between monitor units 15 (1 to n), and the like.

  The correction device 16 performs processing (hereinafter referred to as “correction processing”) for correcting the light intensity (detection value data: P1 to Pn) detected by the monitor unit 15 (1 to n). Specifically, the correction device 16 calculates a noise component (crosstalk component) due to the first crosstalk A based on the detection value data (P1 to Pn) input from the monitor unit 15 (1 to n). . Then, the correction device 16 removes the calculated noise component (crosstalk component) from the detection value data (P1 to Pn) input from the monitor unit 15 (1 to n). Then, the correction device 16 transmits the detection value data (correction value data: X1 to Xn) after removing the noise component (crosstalk component) to the control circuit 13 (1 to n) described later. Thereby, the correction device 16 changes the light intensity of the optical signal (for example, the optical signal output from the optical variable attenuator 12 (1 to n)) actually propagated through the optical transmission path to the control circuit 13 (1 to n). ) Can be notified.

  FIG. 2 is a diagram schematically illustrating an example of a hardware configuration of the correction device 16. The correction device 16 shown in the figure is configured by an arithmetic circuit for calculating correction value data (X1 to Xn) from detection value data (P1 to Pn) according to the following Equation 1.

Xj = Pj−Ra × Σ (i = 1 to n, i ≠ j) Pi (Expression 1)
(However, i and j are integers of 1 to n, and Ra represents the first crosstalk coefficient.)
Specifically, as illustrated, the correction device 16 includes an adder group 161 that performs an operation of “Σ (i = 1 to n, i ≠ j) Pi”, a multiplier 162 (1 to n), A first crosstalk coefficient storage unit 163 and an adder (subtracter) 170 (1 to n) are provided.

  The detection value data (P1 to Pn) input to the correction device 16 is first supplied to the adder 170 (1 to n) and the adder group 161. The adder group 161 calculates “Σ (i = 1 to n, i ≠ j) Pi” for each supplied detection value data Pj (j = 1 to n), and calculates each calculation result to the multiplier 162. (1-n). The multiplier 162 (1 to n) multiplies the calculation result supplied from the adder group 161 and the value Ra of the first crosstalk coefficient stored in the first crosstalk coefficient storage unit 163 in advance. Then, the multiplication value is supplied to the adder (subtracter) 170 (1 to n). An adder (subtracter) 170 (1 to n) multiplies the detection value data (P1 to Pn) supplied from the monitor unit 15 (1 to n) and the multiplier 162 (1 to n). A value obtained by subtracting (subtracting) the value is calculated and output to the control circuit 13 (1 to n) as correction value data (X1 to Xn).

  Here, the processing performed by the adder group 161 (processing for calculating “Σ (i = 1 to n, i ≠ j) P i)” is other than the correction target (jth) optical signal (i = 1 to n). , I ≠ j) corresponds to calculating the sum of the light intensities for the optical signal. This is because the noise component (crosstalk component) added to the optical signal to be corrected is considered to be proportional to the total light intensity of optical signals other than the optical signal to be corrected. Then, the multiplication processing (processing for calculating “Ra × Σ (i = 1 to n, i ≠ j) Pi”) performed by the multiplier 162 (1 to n) is a noise component (first crosstalk A) ( This corresponds to calculating a value corresponding to (crosstalk component). In addition, the subtraction processing (processing for calculating “Pj−Ra × Σ (i = 1 to n, i ≠ j) Pi”) performed by the adder (subtractor) 170 (1 to n) is detected value data (P1 This corresponds to removing a value corresponding to the calculated noise component (crosstalk component) from .about.Pn).

  Note that the first crosstalk coefficient storage unit 163 is realized by a storage device such as a register or a latch circuit, for example. The first crosstalk coefficient stored in advance in the first crosstalk coefficient storage unit 162 has a positive value, and is downstream from the wavelength demultiplexer 10a to the monitor units 15 (1 to n). It is determined according to the characteristics of devices (optical variable attenuator 12, optical coupler 14, monitor unit 15, optical transmission line, etc.) arranged in the section. For example, the higher the number of devices that are likely to generate crosstalk, the higher the value stored in the first crosstalk coefficient storage unit 162.

  FIG. 3 is a diagram illustrating an example of a detailed hardware configuration of the correction device 16 (particularly, “adder group 161”). As illustrated in the dotted line, the adder group 161 includes a plurality of adders 161 (1 to n).

  Each adder 161 (1 to n) is a sum “Σ (i = 1 to n) of light intensities of optical signals other than the correction target (j-th) optical signal (i = 1 to n, i ≠ j). , I ≠ j) Pi ”is calculated and supplied to each multiplier 162 (1 to n) described above.

  The configuration of the correction device 16 shown in FIGS. 2 and 3 is not limited to this. For example, the correction device 16 may be realized by a general computer including a CPU, a RAM, and a storage device (ROM, hard disk, etc.). Then, for example, the CPU can read out a predetermined program from the storage device to the RAM and execute it, so that the above correction process can be realized. Moreover, the correction device 16 may be realized by an FPGA (Field Programmable Gate Array) or the like. Further, it may be realized by an analog circuit.

  Returning to FIG. 1, the control circuit 13 (1 to n) performs control to adjust the light intensity of the optical signal output from the optical variable attenuator 12 (1 to n). Specifically, the control circuit 13 (1 to n), based on the correction value data (X1 to Xn) supplied from the correction device 16, outputs the optical signal output from the optical variable attenuator 12 (1 to n). Control to make the light intensity constant (hereinafter referred to as “constant output control”) is performed.

  For example, in the constant output control, the control circuit 13 (1 to n) compares the correction value data (X1 to Xn) supplied from the correction device 16 with a predetermined target output value set in advance. If the correction value data (X1 to Xn) is equal to the target output value, the attenuation of the optical variable attenuator 12 (1 to n) is not adjusted. The amount of attenuation of the variable attenuator 12 (1 to n) is adjusted. For example, if the correction value data (X1 to Xn) is larger than the target output value, the control circuit 13 (1 to n) increases the attenuation amount of the optical variable attenuator 12 (1 to n). If the correction value data (X1 to Xn) is smaller than the target output value, the attenuation amount of the optical variable attenuator 12 (1 to n) is decreased.

  In addition, the control circuit 13 (1 to n) controls to cut off and recover the optical signal output from the optical variable attenuator 12 (1 to n) (hereinafter referred to as “cutoff control” and “recovery control”, respectively). )I do.

  For example, in the cutoff control, the control circuit 13 (1 to n) compares the correction value data (X1 to Xn) supplied from the correction device 16 with a preset first threshold value. If the correction value data (X1 to Xn) is lower than the first threshold value, the optical signal is determined to be “OFF”, and an optical variable attenuator is used so that no miscellaneous light (noise) is output to the subsequent stage of the optical transmission line. The output light from 12 (1 to n) is blocked.

  In the recovery control, the control circuit 13 (1 to n) compares the correction value data (X1 to Xn) supplied from the correction device 16 with a preset second threshold value. If the correction value data (X1 to Xn) is higher than the second threshold value, it is determined that the optical signal has been restored to the normal level, and the output of the optical signal from the optical variable attenuator 12 (1 to n). Recover (resume).

  Next, FIG. 4 is a flowchart illustrating a correction process performed in the optical transmission device 100 to which the first embodiment is applied.

  The correction device 16 stands by until the light intensity of the single-wavelength optical signal (sub signal) is detected by the monitor unit 15 (1 to n) (Step S101; No). Specifically, the correction device 16 stands by until detection value data (P1 to Pn) is supplied from the monitor unit 15 (1 to n).

  When the monitor unit 15 (1 to n) detects the light intensity of the single-wavelength optical signal (step S101; Yes), the correction device 16 adds a noise component (the first component) added to the detected value data (P1 to Pn). A value corresponding to one crosstalk component) is calculated (step S102).

  Specifically, the adder group 161 generates “Σ (i = 1 to n, i ≠ j) for each detection value data Pj (j = 1 to n) supplied from the monitor unit 15 (1 to n). ) Pi ”, and supplies the operation results to the multipliers 162 (1 to n). Furthermore, the multiplier 162 (1 to n) multiplies the calculation result supplied from the adder group 161 by the value of the first crosstalk coefficient stored in advance in the first crosstalk coefficient storage unit 163. . As a result, the correction device 16 uses the value “Ra × Σ (i = 1 to n, i ≠ j) corresponding to the noise component (first crosstalk component) added to the detection value data (P1 to Pn). Pi "can be calculated.

  Subsequently, the correction device 16 calculates correction value data (X1 to Xn) corrected for the detection value data (P1 to Pn) of the light intensity detected by the monitor unit 15 (1 to n) (step S103). ).

  Specifically, the adder (subtracter) 170 (1 to n) is supplied from the monitor unit 15 (1 to n) when the multiplication value calculated by the multiplier 162 (1 to n) in step S102 is supplied. The multiplied value is subtracted from the detected value data (P1 to Pn). As a result, the correction device 16 corrects the correction value data (X1 to Xn), that is, the optical signal actually propagated through the optical transmission line (for example, the optical signal output from the optical variable attenuator 12 (1 to n)). The light intensity can be calculated.

  Subsequently, the adder (subtracter) 170 (1 to n) of the correction device 16 transmits the correction value data (X1 to Xn) calculated in step S103 to the control circuit 13 (1 to n) (step S104). .

  When the correction device 16 transmits the correction value data (X1 to Xn) to the control circuit 13 (1 to n), the correction process is terminated. The control circuit 13 (1 to n) supplied with the correction value data (X1 to Xn), as described above, based on the supplied correction value data (X1 to Xn), the optical variable attenuator 12 ( 1) -n) “constant output control”, “shut-off control”, “recovery control”, etc.

As described above, the correction device 16 according to the first embodiment can remove the noise component (first crosstalk component) from the light intensity detected by the monitor unit 15 (1 to n). And the control circuit 13 (1-n) can control the optical variable attenuator 12 (1-n) using the correction value data (X1-Xn) from which the noise component (first crosstalk component) is removed. Therefore, the optical transmission device 100 including the correction device 16 can accurately control the optical variable attenuators 12 (1 to n) as compared with the case where the correction value data (X1 to Xn) is not used.
(Second Embodiment)
Hereinafter, another example of the embodiment of the present invention will be described with reference to the drawings.

  FIG. 5 is a schematic configuration diagram of an optical transmission device 100 to which the second exemplary embodiment of the present invention is applied. As illustrated, in addition to the configuration of the optical transmission device 100 to which the first embodiment is applied, the optical transmission device 100 includes the optical transmission direction of the optical transmission device 100 described in the first embodiment (hereinafter, (Referred to as “forward direction”) includes a line in the reverse direction (in the figure, only the wavelength demultiplexer (reverse direction) 10b is shown). Note that the reverse line refers to, for example, an uplink and a downlink in a point-to-point communication path, and a clockwise and counterclockwise line in a ring communication path.

  Further, the optical transmission apparatus 100 to which the second embodiment is applied includes an optical coupler 20a for wavelength multiplexed optical signals (forward direction), a monitor unit 21a for wavelength multiplexed optical signals (forward direction), and wavelength multiplexed light. An optical coupler 20b for signals (reverse direction) and a monitor unit 21b for wavelength multiplexed optical signals (reverse direction) are provided.

  The wavelength-multiplexed optical signal (forward direction) optical coupler 20 a branches the wavelength-multiplexed optical signal (forward direction) input to the optical transmission apparatus 100. Specifically, the optical coupler 20a for wavelength multiplexed optical signal (forward direction) supplies the wavelength multiplexed optical signal (forward direction) input to the optical transmission apparatus 100 to the wavelength demultiplexer (forward direction) 10a. The main signal and the sub signal supplied to the wavelength division multiplexed optical signal (forward direction) monitor unit 21a are branched. Here, the distribution ratio of the main signal and the sub signal is, for example, 9: 1.

  The wavelength division multiplexed optical signal (forward direction) monitor unit 21 a detects the light intensity of the wavelength multiplexed optical signal (forward direction) input to the optical transmission apparatus 100. Specifically, the wavelength division multiplexed optical signal (forward direction) monitoring unit 21a detects the light intensity of the sub signal that is branched and input by the wavelength multiplexed optical signal (forward direction) optical coupler 20a. Then, based on the detected light intensity of the sub-signal, data indicating the light intensity of the wavelength-multiplexed optical signal (forward direction) input to the optical transmission apparatus 100 (forward input detection value data: Σ (i = 1 to n) Pi_FOR ) And transmitted to the correction device 16.

  The optical coupler 20b for wavelength multiplexed optical signals (reverse direction) branches the wavelength multiplexed optical signals (reverse direction) input to the optical transmission apparatus 100. Specifically, the optical coupler 20b for wavelength multiplexed optical signal (reverse direction) supplies the wavelength multiplexed optical signal (reverse direction) input to the optical transmission apparatus 100 to the wavelength demultiplexer (reverse direction) 10b. The main signal and the sub signal supplied to the monitor unit 21b for wavelength multiplexed optical signal (reverse direction) are branched. Here, the distribution ratio of the main signal and the sub signal is, for example, 9: 1.

  The wavelength division multiplexed optical signal (reverse direction) monitor unit 21 b detects the light intensity of the wavelength multiplexed optical signal (reverse direction) input to the optical transmission apparatus 100. Specifically, the wavelength division multiplexed optical signal (reverse direction) monitoring unit 21b detects the light intensity of the sub signal that is branched and input by the optical coupler 20b for wavelength multiplexed optical signal (reverse direction). Then, based on the detected light intensity of the sub-signal, data indicating the light intensity of the wavelength multiplexed optical signal (reverse direction) input to the optical transmission device 100 (reverse direction input detection value data: Σ (i = 1 to n) Pi_REV ) And transmitted to the correction device 16.

  Here, as in the first embodiment, the optical signal (sub signal) input to the monitor unit 15 (1 to n) includes a noise component, and the monitor unit 15 (1 to n) The detection value data (P1 to Pn) to be generated is a value including a noise component. However, in the second embodiment, as a factor that causes noise to be added to the optical signals (sub-signals) input to the monitor units 15 (1 to n), as shown by the thick dotted line in FIG. Consider three crosstalks of a talk A, a second crosstalk B, and a third crosstalk C.

  The first crosstalk A is the same crosstalk as in the first embodiment. The second crosstalk B is crosstalk generated in the wavelength demultiplexer (forward direction) 10a. The third crosstalk C is crosstalk generated in the wavelength demultiplexer (reverse direction) 10b.

  The correction device 16 to which the second embodiment is applied performs a process of correcting the light intensity (detection value data: P1 to Pn) detected by the monitor unit 15 (1 to n), as in the first embodiment. Do. However, the correction device 16 to which the second embodiment is applied performs a correction process different from that of the first embodiment. Specifically, the correction device 16 according to the second embodiment includes a noise component (first crosstalk A) (based on detection value data (P1 to Pn) input from the monitor unit 15 (1 to n)). First crosstalk component) is calculated. At the same time, the correction device 16 uses the noise component (second phase) due to the second crosstalk B based on the forward direction input detection value data (ΣPi_FOR) input from the wavelength division multiplexed optical signal (forward direction) monitor unit 21a. A value corresponding to (crosstalk component) is calculated. Further, the correction device 16 uses the reverse direction input detection value data (ΣPi_REV) input from the wavelength division multiplexed optical signal (reverse direction) monitor unit 21b to generate a noise component (third crosstalk) due to the third crosstalk C. A value corresponding to the talk component is calculated.

  Then, the correction device 16 calculates noise components (first crosstalk component, second crosstalk component, third value) calculated from the detection value data (P1 to Pn) input from the monitor unit 15 (1 to n). The value corresponding to the crosstalk component) is removed. Then, the correction device 16 obtains the detected value data (correction value data: X1 to Xn) after removing the noise components (first crosstalk component, second crosstalk component, third crosstalk component), It transmits to the control circuit 13 (1-n). Thereby, the correction device 16 is more accurate than the first embodiment, and the optical intensity of the optical signal (for example, the optical signal output from the optical variable attenuator 12 (1 to n)) propagating through the optical transmission line is more accurate. Can be notified to the control circuit 13 (1 to n).

  FIG. 6 is a diagram schematically illustrating an example of a hardware configuration of the correction device 16 to which the second embodiment is applied. The correction device 16 shown in the figure is configured by an arithmetic circuit for calculating correction value data (X1 to Xn) from detection value data (P1 to Pn) according to the following Equation 2.

Xj = Pj− {Ra × Σ (i = 1 to n, i ≠ j) Pi + Rb × Σ (i = 1 to n) Pi_FOR + Rc × Σ (i = 1 to n) Pi_REV} (Formula 2)
(Where i and j are integers of 1 to n, Ra is a first crosstalk coefficient, Rb is a second crosstalk coefficient, and Rc is a third crosstalk coefficient.)
Specifically, as illustrated, in addition to the configuration of the correction device 16 of the first embodiment, a second crosstalk coefficient storage unit 165, a third crosstalk coefficient storage unit 166, and a crosstalk provisional A synthesizing adder 169, a crosstalk synthesizing adder 164 (1 to n), a second crosstalk component calculating multiplier 167, and a third crosstalk component calculating multiplier 168; It is equipped with.

  The detected value data (P1 to Pn) input from the monitor unit 15 (1 to n) to the correction device 16 is first supplied to the adder 170 (1 to n) and the adder group 161. The adder group 161 calculates “Σ (i = 1 to n, i ≠ j) Pi” for each supplied detection value data Pj (j = 1 to n), and calculates each calculation result to the multiplier 162. (1-n). The multiplier 162 (1 to n) multiplies the calculation result supplied from the adder group 161 and the value of the first crosstalk coefficient stored in advance in the first crosstalk coefficient storage unit 163. , And supplied to the adders 164 (1 to n) for crosstalk synthesis.

  On the other hand, the forward direction input detection value data (ΣPi_FOR) input from the wavelength division multiplexed optical signal (forward direction) monitor unit 21 a to the correction device 16 is supplied to the second crosstalk component calculation multiplier 167. . The second crosstalk component calculator 167 calculates the supplied forward input detection value data (ΣPi_FOR) and the second crosstalk coefficient stored in advance in the second crosstalk coefficient storage unit 165. The value Rb is multiplied and supplied to the adder 169 for temporary crosstalk synthesis.

  Further, the reverse direction input detection value data (ΣPi_REV) input from the wavelength division multiplexed optical signal (reverse direction) monitor unit 21 b to the correction device 16 is supplied to the third crosstalk component calculation multiplier 168. . The third crosstalk component calculation multiplier 168 calculates the supplied reverse direction input detection value data (ΣPi_REV) and the third crosstalk coefficient stored in advance in the third crosstalk coefficient storage unit 166. The value Rc is multiplied and supplied to the adder 169 for temporary crosstalk synthesis.

  The adder 169 for temporary crosstalk synthesis adds the multiplication values supplied from the second multiplier 167 for calculating the crosstalk component and the third multiplier 168 for calculating the third crosstalk component. , And supplied to the adders 164 (1 to n) for crosstalk synthesis.

  Furthermore, the adders 164 (1 to n) for crosstalk synthesis include the addition value supplied from the adder 169 for temporary crosstalk synthesis, the multiplication value supplied from the multiplier 162 (1 to n), Are added to the adder (subtracter) 170 (1 to n). Then, the adder (subtracter) 170 (1 to n) adds the crosstalk synthesis adder 164 (1 to n) from the detection value data (P1 to Pn) supplied from the monitor unit 15 (1 to n). A value obtained by subtracting the supplied addition value is calculated and output to the control circuit 13 (1 to n) as correction value data (X1 to Xn).

  Here, the multiplication processing (processing for calculating “Rb × Σ (i = 1 to n) Pi_FOR”) performed by the second crosstalk component calculation multiplier 167 is a noise component due to the second crosstalk B. This corresponds to calculating a value corresponding to (second crosstalk component). This is because the second crosstalk component generated in the wavelength demultiplexer (forward direction) 10a is considered to be proportional to the light intensity of the wavelength multiplexed optical signal (forward direction).

  In addition, the multiplication processing (processing for calculating “Rc × Σ (i = 1 to n) Pi_REV”) performed by the third crosstalk component calculation multiplier 168 is a noise component (third crosstalk C). This corresponds to calculating a value corresponding to the third crosstalk component. This is also because the third crosstalk component generated in the wavelength demultiplexer (reverse direction) 10b is considered to be proportional to the light intensity of the wavelength multiplexed optical signal (reverse direction).

  Further, an addition process (“Ra × Σ (i = 1 to n, i ≠ j) Pi + Rb ×) performed by the adder 169 for temporary crosstalk synthesis and the adders 164 (1 to n) for crosstalk synthesis. Σ (i = 1 to n) Pi_FOR + Rc × Σ (i = 1 to n) Pi_REV ”) is the sum of the first crosstalk component, the second crosstalk component, and the third crosstalk component. It corresponds to doing.

  Note that the second crosstalk coefficient storage unit 165 and the third crosstalk coefficient storage unit 166 are realized by a storage device such as a register or a latch circuit, for example. The second crosstalk coefficient stored in advance in the second crosstalk coefficient storage unit 165 is a positive value, and the characteristics of the wavelength demultiplexer (forward direction) 10a and the wavelength demultiplexer (forward Direction) 10a and the distance between the monitor units 15 (1 to n) and the like. The third crosstalk coefficient stored in advance in the third crosstalk coefficient storage unit 166 is a positive value, and the characteristics of the wavelength demultiplexer (reverse direction) 10b and the wavelength demultiplexer (reverse) (Direction) 10b and the distance between the monitor units 15 (1 to n) and the like. Usually, the wavelength demultiplexer (reverse direction) 10b is arranged at a position farther from the monitor unit 15 (1 to n) than the wavelength demultiplexer (forward direction) 10a, and therefore the third crosstalk coefficient is It is often set to a value smaller than 2 crosstalk coefficient.

  FIG. 7 is a diagram illustrating an example of a detailed hardware configuration of the correction device 16 to which the second embodiment is applied. As illustrated, the correction device 16 includes the adder and multiplier described in FIG. 5, and the adder group 161 includes a plurality of adders 161 (1 to n) as in the first embodiment. It has.

  The configuration of the correction device 16 shown in FIGS. 6 and 7 is not limited to this. For example, the correction device 16 may be realized by a general computer including a CPU, a RAM, and a storage device (ROM, hard disk, etc.). Then, for example, the CPU can read out a predetermined program from the storage device to the RAM and execute it, so that the above correction process can be realized. Moreover, the correction device 16 may be realized by an FPGA (Field Programmable Gate Array) or the like. Further, it may be realized by an analog circuit.

  Next, FIG. 8 is a flowchart illustrating a correction process performed in the optical transmission device 100 to which the second embodiment is applied.

  The correction device 16 waits until the light intensity of the wavelength multiplexed optical signal (forward direction) is detected by the monitor unit 21a for wavelength multiplexed optical signal (forward direction) (step S201; No). Specifically, the correction device 16 stands by until forward input detection value data (ΣPi_FOR) is supplied from the wavelength division multiplexed optical signal (forward direction) monitoring unit 21a.

  When the light intensity of the wavelength multiplexed optical signal (forward direction) is detected by the wavelength division multiplexed optical signal (forward direction) monitor unit 21a (step S201; Yes), the correction device 16 detects the forward direction input detection value data (ΣPi_FOR). ) To calculate a value corresponding to the noise component (second crosstalk component B) added (step S202).

  Specifically, the second crosstalk component calculating multiplier 167 includes the forward input detection value data (ΣPi_FOR) supplied from the wavelength division multiplexed optical signal (forward direction) monitor unit 21a, The second crosstalk coefficient value Rb stored in advance in the crosstalk coefficient storage unit 165 is multiplied. Accordingly, the correction device 16 sets the value “Rb × Σ (i = 1 to n) Pi_FOR” corresponding to the noise component (second crosstalk component) added to the forward direction input detection value data (ΣPi_FOR). Can be calculated.

  Subsequently, the correction device 16 waits until the light intensity of the wavelength multiplexed optical signal (reverse direction) is detected by the monitor unit 21b for wavelength multiplexed optical signal (reverse direction) (step S203; No). Specifically, the correction device 16 stands by until the reverse direction input detection value data (ΣPi_REV) is supplied from the wavelength division multiplexed optical signal (reverse direction) monitor unit 21b.

  When the optical intensity of the wavelength multiplexed optical signal (reverse direction) is detected by the wavelength division multiplexed optical signal (reverse direction) monitor unit 21b (step S203; Yes), the correction device 16 detects the reverse direction input detection value data (ΣPi_REV). ) Is calculated as a value corresponding to the noise component (third crosstalk component C) added to () (step S204).

  Specifically, the third crosstalk component calculating multiplier 168 includes the reverse direction input detection value data (ΣPi_REV) supplied from the wavelength division multiplexed optical signal (reverse direction) monitor unit 21b, The third crosstalk coefficient value Rc stored in advance in the crosstalk coefficient storage unit 166 is multiplied. Accordingly, the correction device 16 sets the value “Rc × Σ (i = 1 to n) Pi_REV” corresponding to the noise component (third crosstalk component) added to the reverse direction input detection value data (ΣPi_REV). Can be calculated.

  Subsequently, the correction device 16 calculates the sum of the second crosstalk component and the third crosstalk component (step S205). Specifically, the crosstalk provisional synthesis adder 169 includes the multiplications supplied from the second crosstalk component calculation multiplier 167 and the third crosstalk component calculation multiplier 168. Add values.

  Next, the correction device 16 stands by until the light intensity of the single-wavelength optical signal (sub signal) is detected by the monitor unit 15 (1 to n) (Step S206; No). Specifically, the correction device 16 stands by until detection value data (P1 to Pn) is supplied from the monitor unit 15 (1 to n).

  When the monitor unit 15 (1 to n) detects the light intensity of the single-wavelength optical signal (step S206; Yes), the correction device 16 adds a noise component (the first component) added to the detected value data (P1 to Pn). 1 crosstalk component) is calculated (step S207). Specifically, the same processing as the processing performed in step S102 in the first embodiment is performed. Accordingly, the correction device 16 calculates the noise component (first crosstalk component) “Ra × Σ (i = 1 to n, i ≠ j) Pi” added to the detection value data (P1 to Pn). can do.

  Subsequently, the correction device 16 calculates correction value data (X1 to Xn) corrected for the detection value data (P1 to Pn) of the light intensity detected by the monitor unit 15 (1 to n) (step S208). ).

  Specifically, the adders 164 (1 to n) for crosstalk synthesis use the addition values supplied from the adder 169 for temporary crosstalk synthesis and the multiplications supplied from the multipliers 162 (1 to n). The values are added and supplied to the adder (subtracter) 170 (1 to n). Then, the adder (subtracter) 170 (1 to n) adds the crosstalk synthesis adder 164 (1 to n) from the detection value data (P1 to Pn) supplied from the monitor unit 15 (1 to n). The added value supplied from the above is subtracted. As a result, the correction device 16 corrects the correction value data (X1 to Xn), that is, the optical signal actually propagated through the optical transmission line (for example, the optical signal output from the optical variable attenuator 12 (1 to n)). The light intensity can be accurately calculated.

  Subsequently, the adder (subtracter) 170 (1 to n) of the correction device 16 transmits the correction value data (X1 to Xn) calculated in step S208 to the control circuit 13 (1 to n) (step S209). .

  When the correction device 16 transmits the correction value data (X1 to Xn) to the control circuit 13 (1 to n), the correction process is terminated. Note that the control circuits 13 (1 to n) to which the correction value data (X1 to Xn) are supplied are optically variable based on the supplied correction value data (X1 to Xn), as in the first embodiment. “Output constant control”, “cut-off control”, “recovery control”, etc. of the attenuator 12 (1 to n) are performed.

  As described above, the correction device 16 according to the second embodiment uses the noise components (the first crosstalk component, the second crosstalk component, the third component) from the light intensity detected by the monitor unit 15 (1 to n). Crosstalk component) can be removed. Then, the control circuit 13 (1 to n) uses the correction value data (X1 to Xn) from which the noise components (first crosstalk component, second crosstalk component, and third crosstalk component) are removed. The optical variable attenuator 12 (1 to n) can be controlled. Therefore, the optical transmission device 100 including the correction device 16 can accurately control the optical variable attenuators 12 (1 to n) as compared with the case where the correction value data (X1 to Xn) is not used. In addition, the correction device 16 according to the second embodiment removes many crosstalk components from the light intensity detected by the monitor unit 15 (1 to n) as compared with the first embodiment. The optical variable attenuator 12 (1 to n) can be controlled more accurately.

  9A and 9B are diagrams that quantitatively show the light intensity detected by the monitor unit 15 (1 to n). The horizontal axis represents the light intensity of the optical signal actually propagating through the optical transmission line, and the vertical axis represents the light intensity Pj detected by the monitor unit 15 (1 to n). Therefore, if the value on the horizontal axis and the value on the vertical axis match, this indicates that the detection accuracy in the monitor unit 15 (1 to n) is high, and the more the difference between the value on the horizontal axis and the value on the vertical axis is, This indicates that the detection accuracy in the monitor unit 15 (1 to n) is low.

  FIG. 9A shows the light intensity detected by the monitor unit 15 (1 to n) when the crosstalk component is not removed (when the correction processing is not performed). As shown in the figure, when the crosstalk component is not removed, in the region where the optical intensity of the optical signal actually propagating through the optical transmission line is low (for example, −30 [dBm] or less), the monitor unit 15 (1 The detection accuracy in ~ n) is lowered. Further, as the number of input wavelengths (the number of optical transmission lines) n increases, the crosstalk component input to the monitor unit 15 (1 to n) increases, so that the detection accuracy in the monitor unit 15 (1 to n) increases. Lower.

  On the other hand, FIG. 9B shows the light intensity detected by the monitor unit 15 (1 to n) when the crosstalk component is removed (when the above correction processing is performed). As shown in the figure, when removing the crosstalk component, even if the light intensity of the optical signal actually propagating through the optical transmission path is low, the detection accuracy in the monitor unit 15 (1 to n). Is expensive. Moreover, the detection accuracy in the monitor unit 15 (1 to n) is high regardless of the number of input wavelengths (the number of optical transmission lines) n.

  From the above, it can be said that the monitor unit 15 (1 to n) can accurately detect the light intensity when the correction device 16 performs the correction processing described in the above embodiments. The control circuit 13 (1 to n) adjusts the attenuation amount of the optical variable attenuator 12 (1 to n) based on the light intensity detected by the monitor unit 15 (1 to n). The control of (1-n) is also accurate. In particular, since the above-described “shut-off control” and “recovery control” are controls in a region where the light intensity of the optical signal is low, the correction device 16 performs the correction process in each of the above-described embodiments. Accuracy improves dramatically.

  In addition, this invention is not limited to said each embodiment, A various deformation | transformation and application are possible.

  For example, in each of the above embodiments, the first crosstalk coefficient storage unit 162 stores the first crosstalk coefficient having one value, which is the same for all the multipliers 162 (1 to n). A value is supplied. However, the first crosstalk coefficient storage unit 162 may store first crosstalk coefficients having different values for each wavelength (band) (or for each optical transmission line). In this case, the first crosstalk coefficients having different values are supplied to the multiplications 162 (1 to n).

  In each of the above embodiments, the adder group 161 calculates “Σ (i = 1 to n, i ≠ j) Pi” for each supplied detection value data Pj (j = 1 to n). The sum of the light intensities of all the optical signals other than the correction target (jth) optical signal (i = 1 to n, i ≠ j) is calculated. However, the present invention is not limited to this. For example, the sum of the light intensities of some optical signals other than the correction target (jth) optical signal (i = 1 to n, i ≠ j) may be calculated. Here, a part of the optical signal is composed of only an optical signal adjacent to the correction target (j-th) optical signal, for example.

  In the second embodiment, as shown in FIG. 8, the processes of steps S201 to S202 are performed, the processes of steps S202 to S205 are performed, and then the processes of steps S206 to S207 are performed. I have to. However, the present invention is not limited to this. For example, the processing of steps S202 to S205 may be executed first, and the order of each processing may be arbitrarily changed. Moreover, you may make it perform each process in parallel.

  In the second embodiment, correction for removing the first crosstalk A, the second crosstalk B, and the third crosstalk C is performed. However, the present invention is not limited to this, and correction for removing other noise and other crosstalk generated in the same optical transmission apparatus 100 may be performed.

1 is a schematic configuration diagram of an optical transmission device 100 according to a first embodiment. It is a figure which shows roughly an example of the hardware constitutions of the correction apparatus which concerns on 1st Embodiment. It is a figure which shows an example of the detailed hardware constitutions of the correction apparatus which concerns on 1st Embodiment. It is a flowchart which shows the correction process in 1st Embodiment. It is a schematic block diagram of the optical transmission apparatus which concerns on 2nd Embodiment. It is a figure which shows roughly an example of the hardware constitutions of the correction apparatus which concerns on 2nd Embodiment. It is a figure which shows an example of the detailed hardware constitutions of the correction apparatus which concerns on 2nd Embodiment. It is a flowchart which shows the correction process in 2nd Embodiment. (A) It is a figure which shows the light intensity detected by a monitor part, when not removing a crosstalk component. (B) It is a figure which shows the light intensity detected by a monitor part when a crosstalk component is removed.

Explanation of symbols

10a: Wavelength demultiplexer (forward direction), 10b: Wavelength demultiplexer (reverse direction), 11: Wavelength multiplexer, 12 (1 to n): Optical variable attenuator, 13 (1 to n): control circuit, 14 (1 to n): optical coupler, 15 (1 to n): monitor unit, 16: correction device, 20a: wavelength multiplexed optical signal (Forward) optical coupler, 20b... Wavelength multiplexed optical signal (reverse) optical coupler, 21a... Wavelength multiplexed optical signal (forward) monitor, 21b. Signal (reverse direction) monitor unit, 100... Optical transmission device, 161... Adder group, 162 (1 to n)... Multiplier, 163. 164 (1 to n): adder for crosstalk synthesis, 165: second crosstalk coefficient storage unit, 166: third cross 169 ... multiplier for calculating second crosstalk component, 168 ... multiplier for calculating third crosstalk component, 169 ... adder for temporary crosstalk synthesis , 170 (1 to n): Adder (subtractor).

Claims (11)

A correction device that corrects a detected value detected for the light intensity of each optical signal transmitted for each wavelength,
A noise component calculator that calculates a value corresponding to the noise component added to each optical signal;
Wherein the detection value, e Bei and a noise removing unit that removes the corresponding values in the noise component calculated in the noise component calculation unit,
Each optical signal is demultiplexed for each wavelength from the wavelength multiplexed optical signal,
The noise component calculator is
A first crosstalk component by another optical signal transmitted in parallel with the optical signal to be corrected;
A second crosstalk component by the wavelength multiplexed optical signal before being demultiplexed;
Calculating each value corresponding to the third crosstalk component by the wavelength multiplexed optical signal transmitted in the opposite direction to the optical signal to be corrected;
The noise removing unit
The first crosstalk component, the second crosstalk component, and the third crosstalk component calculated by the noise component calculation unit from the detection value of the optical signal to be corrected, Remove each value corresponding to
A correction device characterized by that. The correction device according to claim 1 ,
The noise component calculator is
To the sum of the detected value of the optical signal other than the optical signal of the correction target, by multiplying a predetermined first coefficient, it calculates a value corresponding to the first crosstalk component,
Multiplying the detection value of the light intensity of the wavelength-multiplexed optical signal before the demultiplexing by a predetermined second coefficient to calculate a value corresponding to the second crosstalk component;
Calculating the detected value of the light intensity for the wavelength-multiplexed optical signal transmitted in the optical signal in the opposite direction of the correction target, by multiplying a predetermined third coefficient, a value corresponding to the third crosstalk component To
A correction device characterized by that. The correction device according to claim 1,
The noise component calculator is
A value corresponding to the first crosstalk component is calculated by multiplying the sum of the detection values for at least some of the optical signals other than the optical signal to be corrected by a predetermined first coefficient. ,
Multiplying the detection value of the light intensity of the wavelength-multiplexed optical signal before the demultiplexing by a predetermined second coefficient to calculate a value corresponding to the second crosstalk component;
Multiply the detection value of the light intensity of the wavelength multiplexed optical signal transmitted in the opposite direction to the optical signal to be corrected by a predetermined third coefficient to calculate a value corresponding to the third crosstalk component To
A correction device characterized by that. A demultiplexing unit that demultiplexes the input wavelength-multiplexed optical signal for each wavelength;
A detection unit for detecting the light intensity of each optical signal demultiplexed by the demultiplexing unit;
An adjustment unit that adjusts the output intensity before Symbol respective optical signals,
A multiplexing unit that combines and outputs each optical signal of the output intensity adjusted by the adjustment unit;
A wavelength division multiplexing optical transmission device comprising:
A noise component calculator that calculates a value corresponding to the noise component added to each optical signal;
A noise removing unit that removes a value corresponding to the noise component calculated by the noise component calculating unit from the light intensity detected by the detecting unit;
The noise component calculator is
A first crosstalk component by another optical signal transmitted in parallel with the optical signal to be corrected;
A second crosstalk component by the wavelength multiplexed optical signal input to the demultiplexing unit;
Calculating each value corresponding to the third crosstalk component by the wavelength multiplexed optical signal transmitted in the opposite direction to the optical signal to be corrected;
The noise removing unit
The first crosstalk component, the second crosstalk component, and the first crosstalk component calculated by the noise component calculation unit from the light intensity of the optical signal to be corrected detected by the detection unit. 3 crosstalk components and the values corresponding to
The adjustment unit is
Adjusting the output intensity of each optical signal based on the light intensity from which the noise component has been removed by the noise removing unit;
A wavelength division multiplexing optical transmission apparatus characterized by the above. The wavelength optical transmission device according to claim 4 ,
The noise component calculator is
To the sum of the light intensity of the optical signal other than the optical signal of the correction target, by multiplying a predetermined first coefficient, it calculates a value corresponding to the first crosstalk component,
Multiplying the light intensity of the wavelength multiplexed optical signal input to the demultiplexing unit by a predetermined second coefficient to calculate a value corresponding to the second crosstalk component;
The light intensity for said wavelength-multiplexed optical signal transmitted in the optical signal in the opposite direction of the correction target, by multiplying a predetermined third coefficient, calculates a value corresponding to the third crosstalk components,
A wavelength division multiplexing optical transmission apparatus characterized by the above.   The wavelength optical transmission device according to claim 4,
  The noise component calculator is
  A value corresponding to the first crosstalk component is calculated by multiplying the sum of the light intensities of at least some of the optical signals other than the optical signal to be corrected by a predetermined first coefficient. ,
  Multiplying the light intensity of the wavelength multiplexed optical signal input to the demultiplexing unit by a predetermined second coefficient to calculate a value corresponding to the second crosstalk component;
  Multiplying the light intensity of the wavelength multiplexed optical signal transmitted in the opposite direction to the optical signal to be corrected by a predetermined third coefficient to calculate a value corresponding to the third crosstalk component;
A wavelength division multiplexing optical transmission apparatus characterized by the above. A correction method in a correction device for correcting a detected value detected for the light intensity of each optical signal transmitted for each wavelength,
The correction device includes a circuit group,
The circuit group is
A noise component calculation process for calculating a value corresponding to the noise component added to each optical signal;
From the detected value, have rows noise removal process and the removal of the value corresponding to the noise component calculated in the noise component calculation process,
Each optical signal is demultiplexed for each wavelength from the wavelength multiplexed optical signal,
The noise component calculation process includes:
A first crosstalk component by another optical signal transmitted in parallel with the optical signal to be corrected;
A second crosstalk component by the wavelength multiplexed optical signal before being demultiplexed;
Calculating each value corresponding to the third crosstalk component by the wavelength multiplexed optical signal transmitted in the opposite direction to the optical signal to be corrected;
The noise removal process
The first crosstalk component, the second crosstalk component, and the third crosstalk component calculated in the noise component calculation process from the detection value of the optical signal to be corrected, Remove each value corresponding to
A correction method characterized by that. The correction method according to claim 7, wherein
The noise component calculation process includes:
Multiplying the sum of the detection values for optical signals other than the optical signal to be corrected by a predetermined first coefficient to calculate a value corresponding to the first crosstalk component;
Multiplying the detection value of the light intensity of the wavelength-multiplexed optical signal before the demultiplexing by a predetermined second coefficient to calculate a value corresponding to the second crosstalk component;
Multiply the detection value of the light intensity of the wavelength multiplexed optical signal transmitted in the opposite direction to the optical signal to be corrected by a predetermined third coefficient to calculate a value corresponding to the third crosstalk component To
A correction method characterized by that. The correction method according to claim 7, wherein
The noise component calculation process includes:
A value corresponding to the first crosstalk component is calculated by multiplying the sum of the detection values for at least some of the optical signals other than the optical signal to be corrected by a predetermined first coefficient. ,
Multiplying the detection value of the light intensity of the wavelength-multiplexed optical signal before the demultiplexing by a predetermined second coefficient to calculate a value corresponding to the second crosstalk component;
Multiply the detection value of the light intensity of the wavelength multiplexed optical signal transmitted in the opposite direction to the optical signal to be corrected by a predetermined third coefficient to calculate a value corresponding to the third crosstalk component To
A correction method characterized by that. A correction device that corrects a detected value detected for the light intensity of each optical signal transmitted for each wavelength,
A noise component calculator that calculates a value corresponding to the noise component added to each optical signal;
A noise removing unit that removes a value corresponding to the noise component calculated by the noise component calculating unit from the detected value;
The noise component calculator is
Multiplying the sum of the detected values for optical signals other than the optical signal to be corrected by a predetermined coefficient to calculate a value corresponding to the crosstalk component,
The noise removing unit
Removing a value corresponding to the crosstalk component calculated by the noise component calculation unit from the detection value of the optical signal to be corrected;
A correction device characterized by that. A demultiplexing unit that demultiplexes the input wavelength-multiplexed optical signal for each wavelength;
A detection unit for detecting the light intensity of each optical signal demultiplexed by the demultiplexing unit;
An adjustment unit for adjusting the output intensity of each optical signal;
A multiplexing unit that combines and outputs each optical signal of the output intensity adjusted by the adjustment unit;
A wavelength division multiplexing optical transmission device comprising:
A noise component calculator that calculates a value corresponding to the noise component added to each optical signal;
A noise removing unit that removes a value corresponding to the noise component calculated by the noise component calculating unit from the light intensity detected by the detecting unit;
The noise component calculator is
Multiplying the sum of the light intensities of the optical signals other than the optical signal to be corrected by a predetermined coefficient to calculate a value corresponding to the crosstalk component,
The noise removing unit
A value corresponding to the crosstalk component calculated by the noise component calculation unit is removed from the light intensity of the optical signal to be corrected detected by the detection unit,
The adjustment unit is
Adjusting the output intensity of each optical signal based on the light intensity from which the noise component has been removed by the noise removing unit;
A wavelength division multiplexing optical transmission apparatus characterized by the above.

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