JP2016201679A - Transmission equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize minimization of power consumption by combining optimization of an injection current to an optical amplifying element and optimization of an injection current to a temperature control element.
An optical reception unit 220 having a function of detecting an optical reception level and transmitting it as an optical reception level notification frame to an opposite device, and an optical reception level notification received from the opposite device when an optical transmission signal is optically amplified. In the optical transmitter 110 equipped with an optical amplifier that adjusts the optical output level of the optical transmission signal and the gain of the optical amplifier according to the opposite optical reception level extracted from the frame, The function of optimizing the drive current of the conversion element is provided, and in the gain adjustment of the optical amplifier of the optical transmission unit 110, the optimization of the injection current to the optical amplification element and the optimization of the injection current to the temperature control element Use together.
[Selection] Figure 1

Description

  The present invention relates to a transmission apparatus, and more particularly to an optical transmission apparatus equipped with an optical amplifier.

  In a transmission apparatus equipped with an optical amplifier, a method for reducing the optical output level of the optical transmission unit on the own apparatus side according to the optical reception level in the opposite apparatus has been studied as a means for saving power. As means for lowering the optical transmission level of the optical transmission unit, a method of lowering an LD (Laser Diode) drive current and a method of lowering the gain of an optical amplifier have been proposed. In general, rare-earth doped fiber amplifiers and Raman amplifiers, which are optical amplifiers used in optical transmission lines, control the temperature of the amplifier for the purpose of stabilizing the wavelength of the pumping light source. Need to keep. Therefore, it is generally assumed that the gain control of the optical amplifier is performed by adjusting the injection current of the pumping light source, and that the injection current is not adjusted to the temperature control unit with high power consumption. Even when semiconductor optical amplifiers with low wavelength dependency are used, the method of keeping the temperature of the optical amplifiers constant has been used so far, minimizing the power consumption of the entire transmission system using the optical amplifiers. It was assumed that could not be realized.

  Japanese Patent Laid-Open No. 2004-228561 uses a method of notifying an optical transmission unit of its own device when a reception error is detected in the optical reception unit of the opposite device, and the optical transmission level of the optical transmission unit of the own device until a reception error occurs. A method for optimizing the drive current of the LD and minimizing only the power consumption of the LD is disclosed.

  Japanese Patent Laid-Open No. 2004-228688 uses a method of calculating an optical reception margin according to an optical reception level in an optical receiving unit of an opposing device and notifying the optical transmission unit of the own device of the optical reception margin information. Discloses a method for optimizing the LD drive current and minimizing only the LD power consumption by reducing the optical output level of the optical transmitter of the optical transmitter according to the optical reception margin information. Has been.

  Patent Document 3 measures the optical transmission level in the optical transmission unit of its own device, measures the optical reception level in the optical reception unit of the opposite device, and transmits information related to the optical reception level to the optical transmission of its own device. The optical amplification is achieved by adjusting the gain of the optical amplifier of the optical transmission unit of the own device using the optical transmission level information measured by the own device and the optical reception level information measured by the opposite device. A method for optimizing the injection current into the device and minimizing only the power consumption of the optical amplifier is disclosed.

JP 2000-165325 A JP 2010-154375 A JP 2012-39287 A

  In a transmission apparatus equipped with an optical amplifier, a method for reducing the optical output level of the optical transmission unit on the own apparatus side according to the optical reception level in the opposite apparatus has been studied as a means for saving power. In Japanese Patent Laid-Open No. 2000-165325, the power consumption of the optical amplifier cannot be minimized, and the power consumption of the temperature control unit of the optical amplifier having the largest power consumption cannot be minimized. Also regarding Japanese Patent Application Laid-Open No. 2010-154375, the power consumption of the optical amplifier cannot be minimized and the power consumption of the temperature control unit of the optical amplifier having the largest power consumption cannot be minimized. Japanese Patent Laid-Open No. 2012-39287 has a problem that the power consumption of the temperature control unit of the optical amplifier with the largest power consumption cannot be minimized.

The present invention has been made in view of the above points, and an object of the present invention is to minimize power consumption by adjusting the optical transmission level of its own apparatus according to the optical reception level of the opposite apparatus.

According to the solution of the present invention,
A drive current control unit for adjusting the drive current value IL of the light emitting element;
An optical amplification element injection current control unit for adjusting an injection current value IA to the optical amplification element of the optical amplification unit;
A temperature control element injection current control unit for adjusting an injection current value IT to the temperature control element of the optical amplification unit; and the drive current control unit, the optical amplification element injection current control unit, and the temperature control element injection current control unit are controlled. And an optical transmission level adjusting unit for adjusting the optical transmission level,
The optical transmission level adjustment unit includes:
(I) When the optical reception level PR in the opposing transmission apparatus exceeds the target optical reception level upper limit PRTmax in a predetermined short cycle T1;
When the IA exceeds a predetermined target injection current value IAT, a light amplification element injection current adjustment process for reducing the IA by a predetermined light amplification element injection current adjustment unit IAi; and
When the IA does not exceed the IAT, if the IL exceeds a predetermined light emitting element minimum driving current value ILmin, the IL is decreased by a predetermined light emitting element driving current adjustment unit ILi. Execute light emitting element drive current adjustment processing,
and,
(Ii) When the PR exceeds the PRTmax at a predetermined long period T2 longer than the T1,
When the IT exceeds the target injection current value ITT, a temperature control element injection current adjustment process for reducing the IT by a predetermined temperature control element injection current adjustment unit ITi is executed.
A transmission device is provided.

According to the present invention, the power consumption can be minimized by adjusting the optical transmission level of the own apparatus according to the optical reception level of the opposite apparatus.

It is a block diagram which shows one of the structural examples of the optical transmission apparatus of a present Example. It is a figure which shows an apparatus operation | movement flowchart. It is a figure which shows the current characteristic of each element of an optical transmission part. It is a figure which shows the electric current transient response characteristic of each element of an optical transmission part. It is a figure which shows the control flowchart by an optical transmission level adjustment part. It is a figure which shows the optical transmission level increase flowchart by an optical transmission level adjustment part. It is a figure which shows the time chart of optical amplification element gain adjustment. It is a figure which shows the time chart of optical amplification element gain adjustment in the case of performing LD drive current adjustment. It is a block diagram which shows one of the structural examples at the time of applying to the transmission system which does not use WDM of a present Example.

  In this embodiment, in a transmission apparatus equipped with an optical amplifier, the gain of the optical amplifier of the own apparatus is adjusted according to the optical reception level in the opposite apparatus, and in order to save power as a transmission system, Regarding the gain adjustment method, the transmission device # 1 100 and the transmission device # that achieve the minimization of power consumption by using the optimization of the injection current to the optical amplification element and the optimization of the injection current to the temperature control element in combination. 2 An example of 200 will be described.

  FIG. 1 is an example of a configuration diagram of a transmission system including a transmission apparatus # 1 100, a transmission apparatus # 2 200, and an optical fiber 300 as a transmission medium in the present embodiment. The operation of each component of the present embodiment will be described with reference to the figure. When the own apparatus is the transmission apparatus # 1 100 and the opposite apparatus is the transmission apparatus # 2 200, the optical signal between the transmission apparatus # 1 100 and the transmission apparatus # 2 200 is a Wavelength Division Multiplexer (hereinafter referred to as WDM). 150 and WDM 250, an optical signal (hereinafter referred to as a downstream optical signal) transmitted from transmission apparatus # 1 100 to transmission apparatus # 2 200 and a transmission apparatus # 2 200 to transmission apparatus # 1 100. An optical signal (hereinafter referred to as an upstream optical signal) is wavelength demultiplexed. As a result, only the downstream optical signal is input to the optical receiver 220. In the optical receiving unit 220, the optical input signal is subjected to photocurrent conversion by a photo diode (hereinafter referred to as PD) 221, current-to-voltage conversion and voltage amplification by a subsequent electric amplification unit 222, and then Media Access Control. The signals are input to the control unit 230 (hereinafter referred to as MAC) and the optical reception level detection unit 223. The optical reception level detection unit 223 performs low-pass filter processing and analog-digital conversion (hereinafter referred to as AD conversion) based on the voltage signal input from the electrical amplification unit 222, and obtains a digital value of the optical reception level. The data is output to the transmission frame generation unit 240. The transmission frame generation unit 240 generates an optical transmission level notification frame from the digital value of the optical reception level input from the optical transmission level detection unit 223 and outputs it to the MAC control unit 230. In the MAC control unit 230, the optical transmission level notification frame is combined with other transmission frames input from the data processing unit 260 to the MAC control unit 230 as transmission data, and is output to the optical transmission unit 210. The optical transmitter 210 photoelectrically converts the transmission data and outputs it to the WDM 250 as an upstream optical signal. The optical transmission level notification frame can be appropriately determined according to the transmission data format, protocol, or the like, such as being included in or added to an existing format. In the WDM 250, the upstream optical signal and the downstream optical signal are wavelength-multiplexed. The wavelength-multiplexed optical signal is transmitted to the transmission apparatus # 1 100 via the optical fiber 300, and only the upstream optical signal is input to the optical receiving unit 120 by the WDM 150 of the transmission apparatus # 1 100. The optical receiver 120 outputs received data to the received frame analyzer 132 in the MAC controller 130 by the same operation as that of the optical receiver 220 of the transmission apparatus # 2 200. The reception frame analysis unit 132 analyzes the reception data input from the optical reception unit 120, and the digital of the optical reception level of the transmission device # 2 200 from the optical transmission level notification frame generated by the transmission device # 2 200. The value is acquired and output to the optical transmission level adjustment unit 115 inside the optical transmission unit 110. In the optical transmission level adjustment unit 115, the LD driving current control unit 116, the optical amplification element injection current control unit 117, and the temperature control element injection current control unit 118 are set for each unit according to the optical reception level of the transmission apparatus # 2 200. Output current control request. In the LD drive current control unit 116, the optical amplification element injection current control unit 117, and the temperature control element injection current control unit 118, the drive current of the LD 111, the optical amplification element 113, and the temperature control according to the respective current control requests. By adjusting the injection currents to the elements 114, the optical output level of the LD 111 and the gain of the optical amplifying unit 112 change, and the optical output level of the transmission apparatus # 1 100 changes. In addition, each part of the same name of the transmission apparatus # 1 100 and the transmission apparatus # 2 200 has the same configuration.

  FIG. 2 is an example of an apparatus operation flowchart in the present embodiment. Device operations of the transmission apparatus # 1 100 and the transmission apparatus # 2 200 of this embodiment will be described with reference to the drawing. The apparatus operation of this embodiment starts when a link is established between the transmission apparatus # 1 100 and the transmission apparatus # 2 200 (sequence 400). After the link is established, the optical receiving unit 220 of the transmission apparatus # 2 200 detects the optical reception level (sequence 401), and transmits the optical reception level notification frame generated based on the optical reception level from the transmission apparatus # 2 200. Periodically generate and send to apparatus # 1 100 (sequence 402). In the transmission apparatus # 1 100, the reception frame analysis unit 132 extracts the optical reception level of the transmission apparatus # 2 200 from the optical reception level notification frame transmitted from the transmission apparatus # 2 200 (sequence 403), and the transmission apparatus # 1 One or more of the drive current of the LD 111, the injection current of the optical amplifying element 113, and the injection current of the temperature control element 114 are changed from the optical transmission level adjustment unit 115 of 100 (sequence 404). Along with this, the optical transmission level of the transmission apparatus # 1 100 varies (sequence 405). By repeating these sequences 401 to 405, the optical transmission level of the transmission apparatus # 1 100 is adjusted and optimized, and the power consumption of the transmission apparatus # 1 100 is minimized. The apparatus operation flowchart is similarly applicable even when the transmission apparatus # 2 200 is the transmission side and the transmission apparatus # 1 100 is the reception side.

  FIG. 3 is an example showing current characteristics of each element of the optical transmitter in this embodiment. An example of the current characteristics of the LD light output level and the optical amplifying element gain of this embodiment will be described with reference to the drawing. As shown in the LD drive current characteristic 500 of the LD light output level, the LD light output level increases in proportion to the LD drive current. Further, as shown in the optical amplification element injection current characteristic 501 of the optical amplification element gain and the temperature control element injection current characteristic 502 of the optical amplification element, the optical amplification element gain is determined by the optical amplification element injection current and the temperature control element injection current. Increase proportionally. In order to increase the gain of the optical amplifying element, it is necessary to flow the temperature control element injection current several times to several tens of times higher than the optical amplification element injection current.

FIG. 4 is an example showing the transient characteristics at the time of current change of each element of the optical transmitter in the present embodiment. As shown in the LD drive current transient characteristic 503 of the LD optical output level, the injection current transient characteristic 504 of the optical amplifying element gain, and the temperature control element injection current transient characteristic 505 of the optical amplifying element gain, the response is achieved in a relatively short time. In contrast to the obtained LD drive current transient characteristic 503 of the LD optical output level and the optical amplification element injection current transient characteristic 504 of the optical amplification element gain, the temperature control element injection current transient characteristic 504 of the optical amplification element gain has several responses. It takes about ten times as long.
Thus, in order to save power, it is most effective to reduce the injection current of the temperature control element that requires the most current as shown in FIG. 3. However, as shown in FIG. Since a long time is required for the amplification element gain response, in this embodiment, the gain adjustment by the temperature control element injection current adjustment is periodically performed, and the gain adjustment by the optical amplification element injection current control having a faster response speed is performed. It is performed in a cycle shorter than the adjustment cycle of gain adjustment by control element injection current adjustment. In addition, when the injection current of the temperature control element and the optical amplifying element is fully reduced and there is a margin for lowering the optical transmission level, the LD drive current is additionally reduced, thereby further minimizing power consumption. 3 and 4 are examples of numerical values representing typical current characteristics, and the present embodiment is not limited only to the described numerical values.

  FIG. 5 is an example showing a control flowchart by the optical transmission level adjusting unit 115 in the present embodiment. The gain adjustment by the temperature control element injection current adjustment is periodically performed using the figure, and the gain adjustment by the optical amplifying element injection current control with a faster response speed is performed. The gain adjustment by the temperature control element injection current adjustment is adjusted. If the injection current of the temperature control element and the optical amplifying element has been lowered and there is a margin to lower the optical transmission level, the light for reducing the LD drive current is added. The optical transmission level adjustment operation by the transmission level adjustment unit 115 will be described.

The optical transmission level adjustment unit 115 executes each sequence as follows.
After the link between the transmission apparatus # 1 100 and the transmission apparatus # 2 200 is established, the optical reception level of the latest transmission apparatus # 2 200 is stored in the optical reception level current value PR in the sequence 600 which is the start sequence, and the timer time T Set to 0. Next, the process proceeds to sequence 601 to determine whether or not PR exceeds the target optical reception level upper limit PRTmax, that is, whether or not there is a room to reduce the optical reception level of transmission apparatus # 2 200 which is the opposite apparatus. If exceeded, the sequence proceeds from the sequence 602 to the temperature control element injection current adjustment phase and the optical amplification element injection current adjustment phase of the sequence 608. On the other hand, when the PR does not exceed PRTmax, the process shifts to sequence 609 and does not shift to the temperature control element injection current adjustment phase and the optical amplification element injection current adjustment phase.
In the temperature control element injection current adjustment phase from the sequence 602, the current injection current value of the temperature control element is stored in the parameter IT (sequence 602). In sequence 603, IT exceeds the target injection current value ITT of the temperature control element. If it exceeds, the optical transmission level adjustment unit 115 sends an instruction signal for decreasing the temperature control element injection current by the temperature control element injection current adjustment unit ITi, to the temperature control element injection current control unit. In response to the instruction, the temperature control element injection current control unit 118 that outputs to 118 and receives the instruction signal decreases the injection current of the temperature control element by ITi (sequence 604). If the IT does not exceed ITT, the process proceeds to sequence 605.
In the optical amplification element injection current adjustment phase from sequence 605, the current injection current value of the optical amplification element is stored in parameter IA (sequence 605). In sequence 606, IA exceeds the target injection current value IAT of the optical amplification element. In the sequence 607, the LD adjustment mode flag is cleared, and the optical transmission level adjustment unit 115 sets the optical amplification element injection current for the optical amplification element injection current adjustment unit IAi. An instruction signal indicating the decrease is output to the optical amplifying element injection current control unit 117. Upon receiving the instruction signal, the optical amplifying element injection current control unit 113 decreases the injection current of the optical amplifying element by IAi according to the instruction. (Sequence 608), transition to Sequence 609.

In sequence 606, when the IA does not exceed IAT, the process proceeds to sequence 615 and the process proceeds to the LD drive current adjustment phase. In the LD drive current adjustment phase, the LD adjustment mode flag is set (sequence 615), and the current value of the LD drive current is stored in the parameter IL (sequence 616). In sequence 617, IL is the minimum drive current value ILmin of LD. If it exceeds, the optical transmission level adjustment unit 115 outputs to the LD drive current control unit 116 an instruction signal to decrease the LD drive current by the LD drive current adjustment unit ILi. Then, the LD drive current control unit 116 that has received the instruction signal reduces the LD drive current by ILi in accordance with the instruction. When the IL does not exceed ILmin, the process proceeds to sequence 609.
In the sequence 609, the processing waits for the time length of the short cycle time T1 which is the LD drive current change transient response and / or the optical amplifying element injection current change transient response standby period (or equivalent to it), and after waiting T is set to T + T1 Update to In sequence 610, it is determined whether or not T is longer than the long period T2 which is the temperature control element injection current change transient response standby period (or equivalent thereto). After the standby period has elapsed, the process proceeds to the initial sequence 600, T is set to 0, and PR is updated to the latest value. Then, the temperature control element injection current adjustment phase, the optical amplification element injection current adjustment phase, and the LD again. The process proceeds to the drive current adjustment phase based on each determination. When T does not exceed T2, that is, during the temperature control element injection current change transient response standby period (long cycle time T2), PR is updated to the latest value (sequence 611), and PR exceeds PRTmax. If it exceeds, the process proceeds to sequence 605 and the process proceeds to the optical amplifying element injection current adjustment phase. If PR does not exceed PRTmax, it is further determined whether PR is below the target optical reception level lower limit PRTmin. If not, transition to sequence 609 because PR is within the target optical reception level range. Then, T is updated and waited, and PR is updated, and each current is not adjusted as long as PR is within the target optical reception level range. When the PR is lower than PRTmin, it means that the optical reception level of the transmission apparatus # 2 200 changed by each current adjustment is excessively lower than the target. Therefore, the optical transmission level shown in FIG. Transition to increasing flow.

The short period T1 and the long period T2 can be appropriately set in advance, and the optical amplification element injection current transient response characteristic of the optical amplification element gain and the temperature control element injection current transient response characteristic of the optical amplification element gain. The adjustment time interval between the optical amplifying element injection current and the temperature control element injection current can be varied. Further, the short cycle time T1 may be a predetermined time that is longer than or equal to one of the LD drive current change transient response and the optical amplifying element injection current change transient response waiting period, or whichever is longer. it can. Further, the long cycle time T2 can be set to a predetermined time equal to or longer than the temperature control element injection current change transient response standby period.
The temperature control element injection current adjustment unit ITi and the optical amplification element injection current adjustment unit IAi can be appropriately set in advance, and the optical amplification element injection current characteristic of the optical amplification element gain and the optical amplification element gain It can be varied according to the temperature control element injection current characteristics, and it is possible to provide a difference in the adjustment time interval between the light amplification element injection current and the temperature control element injection current. Furthermore, the LD drive current adjustment unit ILi can be set as appropriate in advance, and can be varied according to the LD light output level characteristic. This sequence can be similarly applied even when the transmission apparatus # 2 200 is the transmission side and the transmission apparatus # 1 100 is the reception side. In addition, it is also preferable that each parameter value described above can be changed and the setting can be changed.

  FIG. 6 is an example showing an optical transmission level increase flowchart by the optical transmission level adjustment unit 115 in this embodiment. This flow is a flow that moves when the optical reception level of the transmission apparatus # 2 200 that has changed due to each current adjustment is excessively lower than the target (or when it is lower than a predetermined value). The optical transmission level of the transmission apparatus # 1 100 is slightly increased by increasing one or more of the drive current, the optical amplification element injection current, and the temperature control element injection current, thereby the optical reception level of the transmission apparatus # 2 200 It is realized to adjust within the target range.

The optical transmission level adjustment unit 115 executes each sequence as follows.
After starting from sequence 700, it is determined in sequence 701 whether the LD adjustment mode flag is set. If the flag is not set, the process proceeds to sequence 707. If the flag is set, the current value of the LD drive current is stored in IL (sequence 702), and it is determined in sequence 703 whether IL is below the LD maximum drive current value ILmax. If IL is less than ILmax, the LD drive current is increased by ILi (sequence 704). If the IL is not lower than ILmax, the LD adjustment flag is cleared (sequence 705), and the process proceeds to the end sequence 706.
On the other hand, when the LD adjustment mode flag is not set in sequence 701, in sequence 707, the current value of the optical amplifier injection current is stored in IA, and it is determined whether IA is lower than the optical amplifier maximum injection current value IAmax. If it is lower (sequence 708), the optical amplifier element injection current is increased by IAi (sequence 709), and the process proceeds to the end sequence 706. If the IA is not less than IAmax, the process proceeds to sequence 710. In sequence 710, the current temperature control element injection current value is stored in IT, and it is determined whether IT is below the temperature control element maximum injection current value ITmax (sequence 711). Iti is increased (sequence 712), and if the IT is not lower than ITmax, the process proceeds to the end sequence 706. This sequence can be similarly applied even when the transmission apparatus # 2 200 is the transmission side and the transmission apparatus # 1 100 is the reception side. In addition, it is also preferable that each parameter value described above can be changed and the setting can be changed.

FIG. 7 is an example showing a time chart of the optical amplification element gain adjustment in the present embodiment. With reference to the figure, each current adjustment by the optical transmission level adjustment unit 115 and the accompanying optical transmission / reception level, LD optical transmission level, and temporal change of the optical amplification element gain will be described. The LD drive current 802, the optical amplifying element injection current 804, and the temperature control element injection current 805 at the initial point of this adjustment are the maximum injection current values of the respective currents. In order to realize the link establishment (sequence 400) that is the start sequence of the present embodiment, the maximum injection current value ILmax of the LD drive current IL802 is, for example, the maximum rated current value of the LD111 that maximizes the optical output level of the LD111. It can be. Further, the maximum injection current value IAmax of the optical amplifying element injection current IA804 and the maximum injection current value ITmax of the temperature control element injection current IT805 are, for example, an allowable maximum line loss between transmission apparatuses of the transmission system to which the present embodiment is applied ( (Hereinafter referred to as “maximum power budget”), the current value can be satisfied. This is because the transmission line loss between the transmission apparatus # 1 100 and the transmission apparatus # 2 200 (hereinafter referred to as the inter-apparatus line loss) reaches the maximum power budget specification of the transmission system to which this embodiment is applied. This is to realize link establishment between the device # 1 100 and the transmission device # 2 200. That is, when the line loss between devices has a margin with respect to the maximum power budget specification, each current is adjusted, and the optical transmission level of the transmission device # 1 100 is optimized to minimize the power consumption of the transmission device # 1 100. Realize. Whether or not there is a margin with respect to the maximum power budget specification is determined by whether or not the optical reception level PR801 of the transmission apparatus # 2 200 exceeds the target optical reception level upper limit PRTmax. When the optical reception level PR801 exceeds the target optical reception level upper limit PRTmax after the adjustment starts, the temperature control element injection current IT805 is decreased by the temperature control element injection current adjustment unit ITi, and the optical amplification element injection current IA804 is decreased. The optical amplifier element is decreased by the injection current adjustment unit IAi. The temperature control element injection current adjustment unit ITi and the optical amplification element injection current adjustment unit IAi have a difference of several tens of times in the amount of current consumed between the temperature control element and the optical amplification element as shown in FIG. In addition, since there is a difference of several tens of times in the amount of current reduction required to reduce the gain of the same level, for example, the temperature control element injection current adjustment unit ITi is equal to the number of light amplification element injection current adjustment units IAi. Ten times order is preferable. By adjusting the temperature control element injection current IT and the optical amplification element injection current IA, the gain fluctuation amount 806 due to the optical amplification element injection current fluctuation and the gain fluctuation amount 807 due to the temperature control element injection current fluctuation start to change. Here, the gain fluctuation amount 806 due to the fluctuation of the injection current of the optical amplifying element fluctuates relatively immediately according to the fluctuation of the injection current because the transient response is fast as shown in FIG. On the other hand, the gain fluctuation amount 807 due to the temperature control element injection current fluctuation starts to gradually change because the transient response is slow as shown in FIG. Based on this, the adjustment of the injection current of the optical amplifying element is performed at the time interval of the short cycle T1, and the adjustment of the temperature control element injection current is performed at the time interval of the long cycle T2. Note that the short period T1 and the long period T2 have a difference of several tens of times between the optical amplifier injection current fluctuation transient response and the temperature control element injection current fluctuation transient response as shown in FIG. Is preferably on the order of several tens of times the short period T1. The optical amplifying element gain 808 is a time fluctuation obtained by adding the gain fluctuation amount 806 due to the optical amplification element injection current fluctuation and the gain fluctuation amount 807 due to the temperature control element injection current fluctuation. As a result, the optical transmission level 800 of the transmission apparatus # 1 100 varies, and the optical reception level 801 varies. If the optical reception level 801 is equal to or higher than the target optical reception level upper limit, this current adjustment is repeated. Since it takes time for the gain to fluctuate completely by adjusting the injection current of the temperature control element, the light reception level 801 may be transiently below the target light reception level lower limit. In this case, the light shown in FIG. By the operation of the transmission level increase flow, the optical transmission level 800 is slightly increased and the optical reception level 801 is adjusted to be within the target optical reception level range. The time chart can be similarly applied even when the transmission apparatus # 2 200 is the transmission side and the transmission apparatus # 1 100 is the reception side.

7 will be described with reference to the sequence diagrams shown in FIGS. 5 and 6. FIG. In time interval a, sequences 600, 601, 602, 603, 604, 605, 606, 607, and 608 are performed. Then, after waiting for T1 in sequence 609, sequences 610, 611, 612, 605, 606, 607, and 608 are performed at time interval b. Thereafter, after waiting for T1 in sequence 609, the same operation as time break b is performed at time break c, and after waiting for T1 in sequence 609, the same as time break b at time break d The operation is performed. Thereafter, after waiting for T1 in sequence 609, in time interval e, since T ≧ T2, sequences 610, 600, 601, 602, 603, 604, 605, 606, 607, and 608 are performed. After that, after waiting for T1 in sequence 609, sequences 610, 611, 612, 613, and 609 are executed because PRTmin <PR <PRTmax at time interval f. Thereafter, after waiting for T1 in sequence 609, PR <PRTmin is satisfied at time interval g, so sequences 610, 611, 612, 613, 614, 700, 701, 707, 708, 709, 706, 609 are obtained. Is implemented. After that, after waiting for T1 in sequence 609, sequence 610, 611, 612, 613, 609 is executed since PRTmin <PR <PRTmax again in time interval h, and then in sequence 609, T1 After waiting for a while, at time interval i, since T ≧ T2 and PRTmin <PR <PRTmax are maintained, sequences 610, 600, 601, and 609 are performed.

FIG. 8 is an example showing a time chart of the optical amplification element gain adjustment when the LD drive current adjustment is performed in the present embodiment. As shown in this figure, when the optical reception level 801 exceeds the target optical reception level upper limit and when the optical amplification element injection current 803 falls below the target injection current value, the further transmission apparatus # 1 100 The LD drive current 802 is adjusted to minimize power consumption. The adjustment is performed at a time interval of a short period T1, and when the optical amplifying element injection current 803 falls below the target injection current value as described above, the LD drive current decreases by the LD drive current adjustment unit. The time chart can be similarly applied even when the transmission apparatus # 2 200 is the transmission side and the transmission apparatus # 1 100 is the reception side.
The operation of the present embodiment at each time interval a to i shown in FIG. 8 will be described with reference to sequence diagrams shown in FIGS. In time interval a, sequences 600, 601, 602, 603, 604, 605, 606, 607, and 608 are performed. Then, after waiting for T1 in sequence 609, sequences 610, 611, 612, 605, 606, 607, and 608 are performed at time interval b. Thereafter, after waiting for T1 in sequence 609, the same operation as time break b is performed at time break c, and after waiting for T1 in sequence 609, the same as time break b at time break d The operation is performed. Thereafter, after waiting for T1 in sequence 609, in time interval e, since T ≧ T2, sequences 610, 600, 601, 602, 603, 604, 605, 606, 607, and 608 are performed. After that, after waiting for T1 in sequence 609, sequences 610, 611, 612, 605, 606, 607, and 608 are executed at time interval f. After that, after waiting for T1 in sequence 609, IA ≦ IAT and PR> PRTmax are satisfied at time interval g. Therefore, sequences 610, 611, 612, 605, 606, 615, 616, 617, and 618 are executed. Is done. Thereafter, after waiting for T1 in sequence 609, sequences 610, 611, 612, and 613 are executed because PRTmin <PR <PRTmax at time interval h. Thereafter, after waiting for T1 in sequence 609, in time interval i, since T ≧ T2 and PRTmin <PR <PRTmax are maintained, sequences 610, 600, 601 and 609 are performed. .

(Other optical transmission equipment)
In the present embodiment, an example in which the power consumption minimization in the first embodiment is applied to a transmission system that does not use WDM will be described.
FIG. 9 is a block diagram showing one configuration example when applied to a transmission system that does not use WDM according to the present embodiment.
As shown in FIG. 9, this embodiment can be applied to a transmission system that does not use WDM, for example, a two-core bidirectional optical transmission system, and the same effects as those of the first embodiment can be obtained. 9 is different from FIG. 1 only in that the optical wavelength multiplexer / demultiplexer 150 of the transmission device # 1 and the optical wavelength multiplexer / demultiplexer 250 of the transmission device # 2 are not provided, and the other is the same as FIG.

(Effect of Example)
In this embodiment, in a transmission apparatus equipped with an optical amplifier, the gain of the optical amplifier provided in the optical transmission section of the own apparatus is adjusted according to the optical reception level in the opposite apparatus, and power saving as a transmission system is achieved. To achieve this, it is possible to minimize the power consumption by combining the optimization of the injection current to the optical amplifying element and the optimization of the injection current to the temperature control element with respect to the gain adjustment method of the optical amplifier. it can. In addition, according to the present embodiment, it is possible to maintain the optical reception level at which the optical signal can be stably received by the optical reception unit of the opposite device.

(Appendix)
In addition, this invention is not limited to an above-described Example, Various modifications are included. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Further, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.
Each of the above-described configurations, functions, processing units, processing means, and the like may be realized by hardware by designing a part or all of them with, for example, an integrated circuit. Each of the above-described configurations, functions, and the like may be realized by software by interpreting and executing a program that realizes each function by the processor. Information such as programs, tables, and files for realizing each function can be stored in a memory, a hard disk, a recording device such as an SSD (Solid State Drive), or a recording medium such as an IC card, an SD card, or a DVD.
Further, the control lines and information lines indicate what is considered necessary for the explanation, and not all the control lines and information lines on the product are necessarily shown. Actually, it may be considered that almost all the components are connected to each other.

100 Transmission device # 1
110 Optical Transmitter 111 of Transmission Device # 1 LD (Laser Diode) of Transmission Device # 1
112 Optical Amplifying Unit 113 of Transmission Device # 1 Optical Amplifying Element 114 of Transmission Device # 1 Temperature Control Element 115 of Optical Amplifying Element of Transmission Device # 1 Optical Transmission Level Adjusting Unit 116 of Transmission Device # 1 LD Drive of Transmission Device # 1 Current control unit 117 Optical amplification element injection current control unit 118 of transmission device # 1 Temperature control element injection current control unit 120 of transmission device # 1 Optical reception unit 130 of transmission device # 1 MAC control unit 131 of transmission device # 1 Transmission device # 1 transmission frame control unit 132 reception frame analysis unit 140 of transmission device # 1 transmission frame generation unit 150 of transmission device # 1 optical wavelength multiplexer / demultiplexer 160 of transmission device # 1 data processing unit 200 of transmission device # 1 Device # 2
210 Optical Transmitter 220 of Transmission Device # 2 Optical Reception Unit 221 of Transmission Device # 2 PD (Photo Diode) of Transmission Device # 2
222 Electrical amplification unit 223 of transmission device # 2 Optical reception level detection unit 230 of transmission device # 2 MAC control unit 240 of transmission device # 2 Transmission frame generation unit 250 of transmission device # 2 Optical wavelength multiplexing / demultiplexing of transmission device # 2 Device 260 Data Processing Unit 300 of Transmission Device # 2 Optical Fiber 400 to 405 Device Operation Sequence 500 LD Drive Current Characteristic 501 of LD Optical Output Level Optical Amplifying Element Injection Current Characteristic 502 Optical Amplifying Element Gain Temperature Control of Optical Amplifying Element Gain Element injection current characteristic 503 LD drive current transient characteristic 504 of LD light output level Optical amplification element gain optical amplification element injection current transient characteristic 505 Optical amplification element gain temperature control element injection current transient characteristic 600 to 618 By optical transmission level adjustment unit Each sequence 700 to 712 of control flow Optical transmission level increase flow by optical transmission level adjustment unit Sequence 800 optical transmission level time chart 801 of transmission apparatus # 1 optical reception level time chart 802 of transmission apparatus # 2 LD drive current time chart 803 LD optical transmission level time chart 804 optical amplification element injection current time chart 805 temperature control element Injection current time chart 806 Optical amplification element gain fluctuation amount time chart 807 due to fluctuation in optical amplifier element injection current 807 Optical amplification element gain fluctuation time chart 808 due to temperature control element injection current fluctuation 808 Optical amplification element gain time chart

Claims (4)

A drive current control unit for adjusting the drive current value IL of the light emitting element;
An optical amplification element injection current control unit for adjusting an injection current value IA to the optical amplification element of the optical amplification unit;
A temperature control element injection current control unit for adjusting an injection current value IT to the temperature control element of the optical amplification unit; and the drive current control unit, the optical amplification element injection current control unit, and the temperature control element injection current control unit are controlled. And an optical transmission level adjusting unit for adjusting the optical transmission level,
The optical transmission level adjustment unit includes:
(I) When the optical reception level PR in the opposing transmission apparatus exceeds the target optical reception level upper limit PRTmax in a predetermined short cycle T1;
When the IA exceeds a predetermined target injection current value IAT, a light amplification element injection current adjustment process for reducing the IA by a predetermined light amplification element injection current adjustment unit IAi; and
When the IA does not exceed the IAT, if the IL exceeds a predetermined light emitting element minimum driving current value ILmin, the IL is decreased by a predetermined light emitting element driving current adjustment unit ILi. Execute light emitting element drive current adjustment processing,
and,
(Ii) When the PR exceeds the PRTmax at a predetermined long period T2 longer than the T1,
When the IT exceeds the target injection current value ITT, a temperature control element injection current adjustment process for reducing the IT by a predetermined temperature control element injection current adjustment unit ITi is executed.
Transmission device.
The transmission device according to claim 1,
The optical transmission level adjustment unit includes:
When the PR does not exceed the PRTmax at the T2, and further when the PR is below the target optical reception level lower limit PRTmin,
(I) When the IA does not exceed the IAT, if the IL is lower than a predetermined light emitting element maximum driving current value ILmax, the IL is increased by the ILi,
(Ii) When the IA exceeds the IAT, it is determined whether the IA is lower than a predetermined optical amplifier element maximum injection current value IAmax;
If it is lower, the IA is increased by IAi, while if it is not lower, the IT is increased by ITi if the IT is lower than a predetermined temperature control element maximum injection current value ITmax. A transmission device characterized by.
The transmission device according to claim 1,
T1 is a predetermined time equal to or longer than the standby period of the light emitting element driving current change transient response and / or the light amplifying element injection current change transient response,
The T2 is set to a predetermined time equal to or longer than the standby period of the temperature control element injection current change transient response,
The transmission apparatus according to claim 1, wherein the optical transmission level adjustment unit makes a difference in an adjustment time interval between the IL and / or the IA and the IT.
The transmission device according to claim 1,
The IAi is a value determined in advance according to the optical amplifying element injection current characteristic of the optical amplifying element gain,
The ITi is set to a predetermined value according to the temperature control element injection current characteristic of the optical amplification element gain,
The transmission apparatus according to claim 1, wherein the optical transmission level adjustment unit provides a difference in an adjustment time interval between the IA and the IT.

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