KR20190042415A - A optical signal transmitting apparatus including a wavelength tunable laser that is temperature independent and wavelength tunable method using the optical signal transmitting apparatus - Google Patents

Abstract

Disclosed is an optical signal transmitting apparatus including a temperature-unconstrained variable wavelength laser. The optical signal transmitting apparatus comprises: a distributed Bragg reflector (DBR) laser including a DBR mirror region for converting a wavelength of a laser beam output based on a first supply current and an optical gain region for controlling a gain of the output laser beam based on a second supply current; a semiconductor optical amplifier for amplifying the laser beam output from the DBR laser based on a third supply current; and a processor for supplying a compensation current to the optical gain region to suppress a wavelength overshoot due to a carrier effect generated through the first supply current provided to the DBR mirror region according to a wavelength conversion request.

Description

TECHNICAL FIELD [0001] The present invention relates to a wavelength tunable method using an optical signal transmitting apparatus and an optical signal transmitting apparatus including a temperature-independent tunable laser, and a tunable wavelength tuning method using the optical tunable wavelength tunable wavelength tunable wavelength tunable wavelength tunable laser.

[0001] The present invention relates to a wavelength tuning method using an optical signal transmitting apparatus and an optical signal transmitting apparatus including a temperature-independent tunable laser, and more particularly, to a wavelength tuning method using a wavelength tunable laser that compensates for the temperature of a DBR mirror Thereby suppressing the wavelength drift phenomenon.

Recent traffic spikes in data centers are continuing to present problems with data center networking based on electrical switches, such as high power consumption, network latency, limitations of networking scalability, and increased networking costs. In order to solve these problems, optical switch based data center networking having low power, low delay, and scalability characteristics is considered as a source.

The key element in optical switching based systems is wavelength tunable lasers. In order to minimize the loss of information when optical switching is performed, the wavelength tunable laser must be converted at a high speed. Among various wavelength tunable lasers, DBR (Distributed Bragg Reflector) lasers can be controlled at high speed using opto-electronic conversion. However, the temperature increases due to the current supplied to the DBR mirror region for wavelength tuning. This temperature increase phenomenon causes a problem that the oscillation wavelength of the tunable laser deviates from the target wavelength to cause a wave drift phenomenon.

The present invention relates to an apparatus for maintaining a constant temperature of an entire optical signal transmitting apparatus by supplying a compensation current to an optical gain region and a semiconductor optical amplifier in response to a temperature increasing by a current supplied to a DBR mirror region in a DBR wavelength tunable laser, ≪ / RTI >

The optical signal transmitting apparatus according to an embodiment of the present invention includes a DBR mirror region for converting a wavelength of a laser output based on a first supply current and an optical gain control unit for controlling a gain of the laser output based on a second supply current A DBR laser including a region; A semiconductor optical amplifier for amplifying the laser output from the DBR laser based on a third supply current; And a processor for supplying a compensation current to the optical gain region to suppress wavelength overshoot due to a carrier effect generated through a first supply current provided to the DBR mirror region according to a wavelength conversion request, .

The processor may supply a compensation current having an opposite sign to the first supply current to the optical gain region based on a wavelength switching time required by the application to which the DBR laser is applied.

The processor may adjust the magnitude of the compensation current to be proportional to the magnitude of the first supply current.

The optical signal transmitting apparatus according to an embodiment of the present invention includes a DBR mirror region for converting a wavelength of a laser output based on a first supply current and an optical gain control unit for controlling a gain of the laser output based on a second supply current A DBR laser including a region; A semiconductor optical amplifier for amplifying the laser output from the DBR laser based on a third supply current; And a processor for supplying a compensation current to the semiconductor optical amplifier to suppress wavelength drift due to a thermal effect occurring through a first supply current provided to the DBR mirror region in response to a wavelength conversion request have.

The processor may supply a compensation current having an opposite sign to the first supply current to the semiconductor optical amplifier based on a wavelength holding time required by an application to which the DBR laser is applied.

The processor may adjust the magnitude of the compensation current to be proportional to the magnitude of the first supply current.

The optical signal transmitting apparatus according to an embodiment of the present invention includes a DBR mirror region for converting a wavelength of a laser output based on a first supply current and an optical gain control unit for controlling a gain of the laser output based on a second supply current A DBR laser including a region; A semiconductor optical amplifier for amplifying the laser output from the DBR laser based on a third supply current; And a control unit for controlling the optical gain region and the semiconductor optical amplifier in order to suppress a wavelength overshoot and a wavelength drift due to a carrier effect and a temperature effect generated through a first supply current provided to the DBR mirror region according to a wavelength conversion request, 1 compensation current and a second compensation current.

The processor supplies a first compensation current having an opposite sign to the first supply current to the optical gain region based on a wavelength switching time required by an application to which the DBR laser is applied, And supply a second compensation current having the opposite sign to the first supply current to the semiconductor optical amplifier based on the wavelength holding time.

The processor may adjust the magnitude of the first compensation current and the second compensation current to be proportional to the magnitude of the first supply current.

According to an aspect of the present invention, there is provided a wavelength tuning method of a light transmitting apparatus including a temperature-independent DBR laser, the method comprising: providing a first supply current to a DBR mirror region of the DBR laser to convert a wavelength of an output laser; And supplying a compensation current to the optical gain region of the DBR laser to suppress a wavelength overshoot due to a carrier effect occurring through a first supply current provided to the DBR mirror region.

The step of supplying the compensation current may supply a compensation current having an opposite sign to the first supply current to the optical gain region based on the wavelength switching time required by the application to which the DBR laser is applied.

The step of supplying the compensation current may adjust the magnitude of the compensation current so as to be proportional to the magnitude of the first supply current.

According to an aspect of the present invention, there is provided a wavelength tuning method of a light transmitting apparatus including a temperature-independent DBR laser, the method comprising: providing a first supply current to a DBR mirror region of the DBR laser to convert a wavelength of an output laser; And supplying a compensation current to the semiconductor optical amplifier to suppress wavelength drift due to a temperature effect generated through a first supply current provided to the DBR mirror region.

Supplying the compensating current to the semiconductor optical amplifier based on the wavelength holding time required by the application to which the DBR laser is applied, the compensation current having the opposite sign to the first supply current.

The step of supplying the compensation current may adjust the magnitude of the compensation current so as to be proportional to the magnitude of the first supply current.

According to an aspect of the present invention, there is provided a wavelength tuning method of a light transmitting apparatus including a temperature-independent DBR laser, the method comprising: providing a first supply current to a DBR mirror region of the DBR laser to convert a wavelength of an output laser; A first compensation current and a second compensation current are applied to the optical gain region and the semiconductor optical amplifier, respectively, in order to suppress wavelength drift due to a wavelength overshoot and a temperature effect due to a carrier effect generated through a first supply current provided to the DBR mirror region. 2 < / RTI > compensation current.

Wherein the supplying of the first compensation current and the second compensation current comprises supplying a first compensation current having a sign opposite to the first supply current to the optical gain region based on a wavelength switching time required by the application to which the DBR laser is applied And supplies a second compensation current having the opposite sign to the first supply current to the semiconductor optical amplifier based on the wavelength holding time required by the application to which the DBR laser is applied.

The supplying of the first compensation current and the second compensation current may adjust the magnitudes of the first compensation current and the second compensation current to be proportional to the magnitude of the first supply current.

According to an embodiment of the present invention, by supplying a compensation current to the optical gain region and the semiconductor optical amplifier corresponding to the temperature increased by the current supplied to the DBR mirror region in the DBR tunable laser, It can be kept constant.

1 is a diagram illustrating a configuration of an optical signal transmitting apparatus including a DBR laser according to an embodiment of the present invention.
2 is a conceptual diagram illustrating a wavelength drift phenomenon for a DBR laser according to an embodiment of the present invention.
3 is a conceptual diagram for suppressing wavelength drift due to temperature change of a DBR laser according to an embodiment of the present invention.
4 is a graph illustrating a result of suppressing wavelength drift phenomenon through embodiments according to an embodiment of the present invention.
FIG. 5 is a diagram illustrating a hardware embodiment for suppressing wavelength drift due to a temperature change of a DBR laser according to an embodiment of the present invention. Referring to FIG.
6 is a diagram illustrating a software embodiment for suppressing wavelength drift due to temperature change of a DBR laser according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a diagram illustrating a configuration of an optical signal transmitting apparatus including a DBR laser according to an embodiment of the present invention.

The optical signal transmission apparatus includes a DBR laser for outputting an optical signal of a variable wavelength, a semiconductor optical amplifier for amplifying an optical signal output through a DBR laser, and a semiconductor optical amplifier for supplying the DBR laser and a semiconductor optical amplifier (SOA) Lt; RTI ID = 0.0 > currents. ≪ / RTI >

A DBR laser can include two DBR mirrors, where the two DBR mirrors can be of the same type or different types of DBR mirrors. For example, when a DBR laser is a DS (Digital Supermode) -DBR laser, one DBR mirror includes properties having multiple reflection spectra according to wavelengths, and the other DBR mirror is a multi-contact chirped grating. And the like. Alternatively, if the DBR laser is a Sampled Grating (SG) -DBR laser, both DBR mirrors may include attributes with multiple reflection spectra. However, the structure of the DBR laser provided in the present invention is not limited to any one, and the properties and shape of the DBR mirror may be changed depending on the type of the DBR laser.

1, an optical signal transmission apparatus 100 according to an exemplary embodiment of the present invention includes a DBR laser 110 for outputting an optical signal having a variable wavelength, A semiconductor optical amplifier 120 and a processor 130 for controlling a supply current supplied to the DBR laser 110 and the semiconductor optical amplifier 120. At this time, the DBR laser 110 includes a front grating (FG) region 111 having a multi-contact chirping grating shape, a rear grating (RG) region 112 having an attribute having multiple reflection spectra, A gain region 113 and a phase region 114. [ In one example, the processor may be an FPGA (Field Programmable Gate Array).

The look-up table of the processor 130 may set the supply currents to be supplied to the respective regions of the DBR laser 110 and the semiconductor optical amplifier 120 for each wavelength. The FG region 111, the RG region 112 and phase region 114 may be provided with supply currents using a high performance DAC, such as a 16-bit digital analog converter (DAC). Alternatively, supply currents can be provided using a low performance DAC, such as a 14-bit DAC, because the active tuning regions, such as the optical gain region 113 and the semiconductor optical amplifier 120, are relatively less sensitive to current variations. The supply current provided to the FG region 111 must be provided to the contacts of the adjacent FG regions for a single wavelength operation so that the number of DACs required to drive the eight FG regions 111 adds two 1 x 4 electrical switches Can be reduced to two.

At this time, the processor 130 may control an analog current provided through the DAC to provide a current driver to the RG region 112, the optical gain region 113, and the semiconductor optical amplifier 120 at the same time. The method of suppressing the wavelength drift phenomenon of the optical signal transmitting apparatus 100 provided in the present invention can be applied not only to a DS-DBR laser but also to a general DBR laser such as an SG-DBR laser. Accordingly, the processor 130 may determine the optical gain region 113 and the semiconductor optical signal (wavelength) in consideration of the supply currents provided to other regions (the FG region 111, the phase region 114, and the like) Adjustment of the supply currents provided to the amplifier 120 may be possible. Two TEC (ThermoElectric Cooler) drivers can maintain the temperature of the internal components and provide long-term wavelength stability.

A process of providing the supply currents to the respective regions of the optical signal transmitting apparatus 100 will be described. First, the processor 130 can output a digital signal with reference to a lookup table. At this time, the look-up table may include information on a supply current supplied to each region of the optical signal transmitting apparatus 100 required for the DBR laser 110 to output optical signals of various wavelengths. For example, the look-up table may store first supply currents provided to the RG region 112 for each output wavelength, a second supply current provided to the optical gain region 113, A constant value can be stored regardless of the wavelength.

The output digital signal is then converted into an analog current in the DAC corresponding to each region of the DBR laser 110 and the converted analog current is supplied to the corresponding optical signal transmitting device 100 through each current driver DR, As shown in FIG.

2 is a conceptual diagram of wavelength drift phenomenon in an optical signal transmitting apparatus according to an embodiment of the present invention.

Referring to FIG. 2, the concept that wavelength drift phenomenon occurs in the optical signal transmitting apparatus 100 can be confirmed. In order for the DBR laser 110 to output an optical signal having a converted wavelength in a wide wavelength band, a current of several tens of mA must be provided to the DBR mirror region (corresponding to the RG region in FIG. 1) of the DBR laser 110. That is, the optical signal transmission apparatus 100 can provide the first supply current to the RG region 112 of the DBR laser 110 by referring to the lookup table of the processor 130 to change the wavelength of the optical signal to be output have. Here, if the oscillation wavelength of the optical signal currently output through the DBR laser 110 is a lambda _{Start channel} , a target wavelength of the optical signal to which a current of several tens mA is output is set as a lambda _{Destination Channel} .

When a first supply current of several tens of mA is provided to the RG region 112 of the DBR laser 110 to convert the output wavelength of the output optical signal from the? _{Start Channel} to the? _{Destination Channel} , The wavelength of the optical signal is the same as that shown in Fig. That is, if a first supply current of several tens of mA is provided to the RG region 112 of the DBR laser 110, a wavelength overshoot may occur in which the wavelength of the optical signal output in the time domain in which the carrier effect occurs is shifted.

The temperature of the DBR laser 110 is increased due to the first supply current provided to the RG region 112, and the refractive index of the DBR laser 110 is decreased, so that the wavelength of the output optical signal can be increased. The phenomenon that the output wavelength of the optical signal output through the DBR laser 110 is deviated from the λ _{destination channel} which is the target wavelength due to the temperature increase is referred to as a wavelength drift phenomenon by the temperature effect. Since the wavelength drift phenomenon due to the temperature effect occurs in the time domain of several hundred milliseconds or more, information can not be transmitted or exchanged in the optical switching based system during the corresponding time.

3 is a conceptual diagram for suppressing wavelength drift due to temperature change of a DBR laser according to an embodiment of the present invention.

If a first supply current of several tens of mA is provided to the RG region 112 of the DBR laser 110 to change the wavelength of the optical signal to be output, a wavelength overshoot due to the carrier effect and a wavelength drift phenomenon due to the temperature effect appear . In order to suppress such a wavelength drift phenomenon, the present invention provides a first compensation current to the optical gain region 113 of the DBR laser 110 corresponding to the carrier effect of the DBR laser 110, (100) by supplying a second compensation current to the optical signal transmission apparatus (120). The first compensation current to be supplied to the optical gain region 113 and the first compensation current to be supplied to the semiconductor optical amplifier 120 are determined by the magnitude of the first supply current supplied to the RG region 112 of the DBR laser 110, . ≪ / RTI > The reason why the difference between the optical gain region 113 and the semiconductor optical amplifier 120 occurs is that the optical gain region 113 is a section constituting a resonator of the DBR laser 110 and the semiconductor optical amplifier 120 is a DBR And is thermally coupled only to the outside of the resonator of the laser 110.

3, there is almost no first supply current provided to the RG region 112 of the DBR laser 110 at the start channel (I _RG = 0 mA), and the optical gain region 113 The second supply current I ' _Gain and the third supply current I' _SOA provided to the semiconductor optical amplifier 120 and the semiconductor optical amplifier 120 may have a constant size.

At this time, the optical signal transmission apparatus 100 transmits the optical signal to the RG region 112 of the DBR laser 110 in order to convert the wavelength of the optical signal to be outputted (i.e., to switch the wavelength to the destination channel) the first supply current I _RG of mA can be increased. As described above, in response to the wavelength drift phenomenon caused by the first supply current I _RG provided to the RG region 112, the optical signal supply apparatus 100 of the present invention starts using the processor 130 in the optical gain region 113, or the semiconductor optical amplifier 120 in each channel _gain and ΔI ΔI is possible to suppress the wavelength drift phenomenon by supplying the first compensation and the second compensation current by a current of _SOA.

4 is a graph illustrating a result of suppressing wavelength drift phenomenon through embodiments according to an embodiment of the present invention.

4 is an experimental result showing that the wavelength drift phenomenon of the entire optical signal transmission apparatus 100 is suppressed when a compensation current is supplied to the optical gain region 113 of the DBR laser 110 and the semiconductor optical amplifier 120 . For example, the optical gain region 113 and the semiconductor optical amplifier 120 in the start channel are constantly provided with I ' _Gain of a predetermined size, that is, a second supply current and an I' _SOA, that is, a third supply current.

1 shows a change in wavelength with time when a first supply current of 60 mA is supplied at 0 mA to the RG region 112 of the DBR laser 110 without supplying any compensation current. (I ' _Gain = I _Gain , I' _SOA = I _SOA ) where there is no change in the supply currents provided to the optical gain region 113 and the semiconductor optical amplifier 120 in the start channel and the destination channel . Referring to the graph of the output wavelength, a wavelength allowable range 400 allowed by the OIF (Optical Internetworking Forum) standard is used in both the time domain 410 where the carrier effect occurs and the time domain 420 where the temperature effect occurs It can be seen that it is far removed.

In response to such a wavelength overshoot due to the carrier effect, the optical signal transmitting apparatus 100 of the present invention can supply the first compensation current of the magnitude of ΔI _Gain to the optical gain region 113 in the start channel. The first compensation current supplied at this time may be adjusted in proportion to the magnitude of the first supply current with the opposite sign to the first supply current.

The graph (2) shows a change in the wavelength with time when the first compensation current is supplied to the optical gain region 113 as described above. Referring to the graph of the output wavelength, the carrier effect is reduced through the first compensation current supplied to the optical gain region 113 of the start channel such that the output wavelength in the time domain 410 is within the wavelength tolerance range 400 ) Is satisfied. Since the temperature of the laser is slightly changed through the supply of the first compensation current, it can be confirmed in the time domain 420 that the carrier drift phenomenon due to the temperature effect is suppressed to some extent as well as the carrier effect.

However, the temperature compensation of the DBR laser 110 is not completely compensated despite the first compensation current supplied to the optical gain region 113, so that the wavelength drift due to the temperature effect still occurs.

In response to the wavelength drift phenomenon caused by the temperature effect, the optical signal transmission apparatus 100 of the present invention can supply the second compensation current of the ΔI _SOA size to the semiconductor optical amplifier 120 in the start channel. The second compensation current supplied at this time may be adjusted in proportion to the magnitude of the first supply current with the opposite sign to the first supply current.

The graph (3) shows a change in wavelength with time when a compensation current is supplied to both the optical gain region 113 and the semiconductor optical amplifier 120. Referring to the graph of the output wavelength, the carrier effect is reduced through the first compensation current supplied to the optical gain region 113 of the start channel such that the output wavelength in the time domain 410 is within the wavelength tolerance range 400 ) Is satisfied. Further, the temperature effect is reduced through the second compensation current supplied to the semiconductor optical amplifier 120 of the start channel to confirm that the output wavelength in the time domain 420 satisfies the wavelength tolerance range 400 allowed by the OIF standard .

FIG. 5 is a diagram illustrating a hardware embodiment for suppressing wavelength drift due to a temperature change of a DBR laser according to an embodiment of the present invention. Referring to FIG.

Referring to FIG. 5, the optical signal transmitting apparatus 100 of the present invention can suppress wavelength drift phenomenon due to temperature change due to wavelength conversion through simple modification of internal hardware without modifying the laser process. Specifically, the optical signal transmission apparatus 100 controls the current driver (DR) 140 having the differential output corresponding to the RG region 112 of the DBR laser 110 to output the first supply current to the RG region 112 Can supply. The temperature of the RG region 112 may be increased by the first supply current supplied in this way, and this temperature increase may cause the wavelength drift due to the wavelength overshoot and the temperature effect due to the carrier effect. Therefore, there is an advantage that the laser module can be easily upgraded by changing the driving circuit for the laser module that has already been supplied.

≪ Embodiment 1 >

The optical signal transmission apparatus 100 can suppress the wavelength overshoot due to the carrier effect generated by providing the first supply current to the RG region 112 of the DBR laser 110 according to the wavelength conversion request. In other words, the first embodiment may be suitable for an application in which switching of wavelengths in the time domain 410 is completed and an optical signal having a stabilized wavelength is output.

Specifically, the optical signal transmission apparatus 100 controls the current driver 140 corresponding to the RG region 112 in the start channel to output a first compensation current having a sign opposite to the sign of the first supply current to the DBR laser 110 To the optical gain region 113 of the light-receiving element. At this time, the optical signal transmitting apparatus 100 can adjust the magnitude of the first compensation current using a separate current regulator 150a. The current regulator 150a adjusts the magnitude of the compensation current in proportion to the magnitude of the first supply current. Can be adjusted. Here, the current regulator 150a may be an element capable of amplifying or attenuating the gain of the electric signal (G / A, Electrical Gain / Attenuation). The thus adjusted first compensation current may be supplied to the optical gain region 113 by being coupled to the second supply current continuously supplied to the optical gain region 113 through the electrical adder 160a.

The optical signal transmission apparatus 100 then performs a wavelength switching by providing a first supply current to the RG region 112 and simultaneously reduces the magnitude of the second supply current provided to the optical gain region 113 by the first compensation current . Through such operation, the optical signal transmission apparatus 100 can suppress the wavelength drift phenomenon with respect to the output wavelength in the time domain 410 by reducing the carrier effect.

≪ Embodiment 2 >

The optical signal transmission apparatus 100 can suppress the wavelength drift phenomenon due to the temperature effect generated by providing the first supply current to the RG region 112 of the DBR laser 110 according to the wavelength conversion request. In other words, the second embodiment may be suitable for an application that maintains the wavelength of the wavelength-switched optical signal in the time domain 420.

More specifically, the optical signal transmission apparatus 100 controls the current driver 140 corresponding to the RG region 112 to output a second compensation current having a sign opposite to that of the first supply current to the semiconductor optical amplifier 120 Can supply. At this time, the optical signal transmitting apparatus 100 can adjust the magnitude of the second compensation current by using a separate current regulator 150b. The current regulator 150b adjusts the magnitude of the second compensation current Can be adjusted. The current regulator 150b may be an element capable of amplifying or attenuating the gain of the electric signal. The thus adjusted second compensation current may be supplied to the semiconductor optical amplifier 120 by coupling the third supply current continuously supplied to the semiconductor optical amplifier 120 through the electrical adder 160b.

The optical signal transmission apparatus 100 then performs a wavelength switching by providing a first supply current to the RG region 112 and at the same time reduces the magnitude of the third supply current supplied to the semiconductor optical amplifier 120 by the second compensation current . Through such operation, the optical signal transmission apparatus 100 can suppress the wavelength drift phenomenon with respect to the output wavelength in the time domain 420 by reducing the temperature effect.

≪ Third Embodiment >

The optical signal transmission apparatus 100 transmits the first supply current to the RG region 112 of the DBR laser 110 in accordance with the wavelength conversion request to generate a wavelength drift due to a wavelength overshoot and a temperature effect due to a carrier effect . In other words, the third embodiment is suitable for an application in which switching of wavelengths is completed in the time domain 410 to output an optical signal having a stabilized wavelength, and a wavelength of a wavelength-switched optical signal is maintained in the time domain 420 can do.

Specifically, the optical signal transmission apparatus 100 controls the current driver 140 corresponding to the RG region 112 to output a first compensation current having a sign opposite to that of the first supply current to the light of the DBR laser 110 To the gain region 113 and supply a second compensation current having a sign opposite to that of the first supply current to the semiconductor optical amplifier 120. [ At this time, the optical signal transmission apparatus 100 can adjust the magnitude of the compensation currents using the current controllers 150a and 150b. The current controllers 150a and 150b adjust the compensation currents in proportion to the magnitude of the first supply current. Can be adjusted. Here, the current regulators 150a and 150b may be elements capable of amplifying or attenuating the gain of the electric signal. The first compensating current and the second compensating current having the magnitudes adjusted in this way are supplied to the semiconductor optical amplifier 120 and the semiconductor optical amplifier 120 in such a manner that the second supply current continuously supplied to the optical gain region 113 and the third supply current continuously supplied to the semiconductor optical amplifier 120, And may be supplied to the optical gain region 113 and the semiconductor optical amplifier 120 through the adders 160a and 160b.

The optical signal transmission apparatus 100 then performs a wavelength switching by providing a first supply current to the RG region 112 and simultaneously reduces the magnitude of the second supply current provided to the optical gain region 113 by the first compensation current And reduce the magnitude of the third supply current provided to the semiconductor optical amplifier 120 by the second compensation current. Through such operation, the optical signal transmission apparatus 100 reduces the carrier effect to suppress the wavelength overshoot with respect to the output wavelength in the time domain 410, and decreases the temperature effect to reduce the output wavelength in the time domain 420 It is possible to suppress the wavelength drift phenomenon.

Such a hardware implementation method is advantageous in that time synchronization can be easily adjusted by supplying a compensation current using a current driver having a differential output corresponding to the RG region 112 of the DBR laser 110. [ In addition, although the supply current ideally has a waveform of a step function, actually, the waveform of each drive driver may be different from each other. However, when the supply current is supplied to the RG region 112 by using only one differential driver and the compensation current is supplied to the optical gain region 113 and the semiconductor optical amplifier 120, since the same drive driver is used, There is an advantage to be able to drive. Finally, since the compensation current of the optical gain region 113 and the semiconductor optical amplifier 120 is supplied in proportion to the magnitude of the supply current supplied to the RG region 112 without modification of the lookup table, the magnitude of the compensation current is automatically adjusted There are advantages to be able to.

6 is a diagram illustrating a software embodiment for suppressing wavelength drift due to temperature change of a DBR laser according to an embodiment of the present invention.

Referring to FIG. 6, the optical signal transmitting apparatus 100 of the present invention can suppress the wavelength drift phenomenon by using a software method. To this end, the optical signal transmission apparatus 100 may modify the look-up table of the processor 130 for driving the DBR laser 110. In general, the processor 130 of the optical signal transmission apparatus 100 calculates a first supply current of the RG region 112, a second supply current of the optical gain region 112 corresponding to the wavelength of the optical signal to be output, And the third supply current of the semiconductor optical amplifier 120 is stored in a look-up table.

Therefore, the optical signal transmitting apparatus 100 of the present invention transmits the optical gain region 113 of the DBR laser 110 stored for each wavelength to be output to the lookup table and the supply The currents can be modified. At this time, the supply currents supplied to the optical gain region 113 and the semiconductor optical amplifier 120 to be corrected are respectively the first compensation current and the second compensation current, which are determined through the first supply current supplied to the RG region 112, As shown in FIG.

The compensation currents supplied to the optical gain region 113 and the semiconductor optical amplifier 120 are generally smaller than the first supply current value supplied to the RG region 112 . More specifically, the compensation current value is determined by applying the maximum switching current value of the RG region 112, finding the compensation currents of the corresponding maximum optical gain region 113 and the semiconductor optical amplifier 120, The compensation current values of the optical gain region 113 and the semiconductor optical amplifier 120 can be adjusted in proportion to the switching current value. In this case, when the compensation current value is found, if the compensation current value is found in a large current unit, the compensation current value can be obtained quickly, but the wavelength stability (accuracy) may be lowered. Conversely, if we find it in small current units, we can know the compensated current value with high wavelength stability (accuracy), though it is slow.

The optical signal transmission apparatus 100 adds the determined compensation current value to the second supply current and the third supply current that are continuously supplied to the optical gain region 113 and the semiconductor optical amplifier 120 in the start channel You can modify the lookup table.

In step 620, the optical signal transmission apparatus 100 may control and supply the first supply current of the RG region 112 corresponding to the wavelength to be converted through the processor 130, referring to the modified lookup table .

Thereafter, in step 630, the optical signal transmission apparatus 100 refers to the modified look-up table to suppress the wavelength drift phenomenon that may occur due to the first supply current, The supply current and the third supply current of the semiconductor optical amplifier can be supplied through the control of the processor 130. [

In step 640, the optical signal transmitting apparatus 100 can determine whether a wavelength drift phenomenon has occurred by checking the wavelength of the output optical signal.

If the wavelength drift phenomenon does not occur, the optical signal transmission apparatus 100 stores the modified lookup table in step 650 and repeats steps 610 to 630 if the wavelength drift phenomenon occurs to obtain the optimum compensation current You can repeat the search process.

Meanwhile, the method according to the present invention may be embodied as a program that can be executed by a computer, and may be embodied as various recording media such as a magnetic storage medium, an optical reading medium, and a digital storage medium.

Implementations of the various techniques described herein may be implemented in digital electronic circuitry, or in computer hardware, firmware, software, or combinations thereof. Implementations may be implemented in a computer program product, such as an information carrier, e.g., a machine readable storage device, such as a computer readable storage medium, for example, for processing by a data processing apparatus, Apparatus (computer readable medium) or as a computer program tangibly embodied in a propagation signal. A computer program, such as the computer program (s) described above, may be written in any form of programming language, including compiled or interpreted languages, and may be stored as a stand-alone program or in a module, component, subroutine, As other units suitable for use in the present invention. A computer program may be deployed to be processed on one computer or multiple computers at one site or distributed across multiple sites and interconnected by a communications network.

Processors suitable for processing a computer program include, by way of example, both general purpose and special purpose microprocessors, and any one or more processors of any kind of digital computer. Generally, a processor will receive instructions and data from a read-only memory or a random access memory or both. The elements of a computer may include at least one processor for executing instructions and one or more memory devices for storing instructions and data. Generally, a computer may include one or more mass storage devices for storing data, such as magnetic, magneto-optical disks, or optical disks, or may receive data from them, transmit data to them, . ≪ / RTI > Information carriers suitable for embodying computer program instructions and data include, for example, semiconductor memory devices, for example, magnetic media such as hard disks, floppy disks and magnetic tape, compact disk read only memory A magneto-optical medium such as a floppy disk, an optical disk such as a DVD (Digital Video Disk), a ROM (Read Only Memory), a RAM , Random Access Memory), a flash memory, an EPROM (Erasable Programmable ROM), an EEPROM (Electrically Erasable Programmable ROM), and the like. The processor and memory may be supplemented or included by special purpose logic circuitry.

In addition, the computer-readable medium can be any available media that can be accessed by a computer, and can include both computer storage media and transmission media.

While the specification contains a number of specific implementation details, it should be understood that they are not to be construed as limitations on the scope of any invention or claim, but rather on the description of features that may be specific to a particular embodiment of a particular invention Should be understood. Certain features described herein in the context of separate embodiments may be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment may also be implemented in multiple embodiments, either individually or in any suitable subcombination. Further, although the features may operate in a particular combination and may be initially described as so claimed, one or more features from the claimed combination may in some cases be excluded from the combination, Or a variant of a subcombination.

Likewise, although the operations are depicted in the drawings in a particular order, it should be understood that such operations must be performed in that particular order or sequential order shown to achieve the desired result, or that all illustrated operations should be performed. In certain cases, multitasking and parallel processing may be advantageous. Also, the separation of the various device components of the above-described embodiments should not be understood as requiring such separation in all embodiments, and the described program components and devices will generally be integrated together into a single software product or packaged into multiple software products It should be understood.

It should be noted that the embodiments of the present invention disclosed in the present specification and drawings are only illustrative of specific examples for the purpose of understanding and are not intended to limit the scope of the present invention. It will be apparent to those skilled in the art that other modifications based on the technical idea of the present invention are possible in addition to the embodiments disclosed herein.

100: optical signal transmitting device
110: DBR laser
111: DBR mirror area
112: optical gain region
113: phase region
120: semiconductor optical amplifier
130: Processor

Claims (18)

A DBR laser including a DBR mirror region for converting a wavelength of a laser output based on a first supply current and an optical gain region for controlling a gain of the output laser based on a second supply current;
A semiconductor optical amplifier for amplifying the laser output from the DBR laser based on a third supply current; And
And a controller for supplying a compensation current to the optical gain region to suppress a wavelength overshoot due to a carrier effect generated through a first supply current provided to the DBR mirror region according to a wavelength conversion request,
And outputs the optical signal. The method according to claim 1,
The processor comprising:
And supplies a compensation current having an opposite sign to the first supply current to the optical gain region based on a wavelength switching time required by an application to which the DBR laser is applied. The method according to claim 1,
The processor comprising:
And adjusts the magnitude of the compensation current so as to be proportional to the magnitude of the first supply current. A DBR laser including a DBR mirror region for converting a wavelength of a laser output based on a first supply current and an optical gain region for controlling a gain of the output laser based on a second supply current;
A semiconductor optical amplifier for amplifying the laser output from the DBR laser based on a third supply current; And
A semiconductor optical amplifier for supplying a compensation current to the semiconductor optical amplifier for suppressing a wavelength drift due to a temperature effect generated through a first supply current provided to the DBR mirror region according to a wavelength conversion request;
And outputs the optical signal. 5. The method of claim 4,
The processor comprising:
And supplies a compensation current having an opposite sign to the first supply current to the semiconductor optical amplifier based on a wavelength holding time required by an application to which the DBR laser is applied. 5. The method of claim 4,
The processor comprising:
And adjusts the magnitude of the compensation current so as to be proportional to the magnitude of the first supply current. A DBR laser including a DBR mirror region for converting a wavelength of a laser output based on a first supply current and an optical gain region for controlling a gain of the output laser based on a second supply current;
A semiconductor optical amplifier for amplifying the laser output from the DBR laser based on a third supply current; And
The semiconductor optical amplifier according to any one of claims 1 to 3, wherein the semiconductor optical amplifier includes a plurality of semiconductor optical amplifiers, 1 < / RTI > compensation current < RTI ID = 0.0 >
And outputs the optical signal. 8. The method of claim 7,
The processor comprising:
Supplying a first compensation current having an opposite sign to the first supply current to the optical gain region based on a wavelength switching time required by an application to which the DBR laser is applied,
And supplies a second compensation current having an opposite sign to the first supply current to the semiconductor optical amplifier based on a wavelength holding time required by an application to which the DBR laser is applied. 8. The method of claim 7,
The processor comprising:
And adjusts the magnitudes of the first compensation current and the second compensation current so as to be proportional to the magnitude of the first supply current. A wavelength tuning method of an optical transmitter including a temperature-independent DBR laser,
Providing a first supply current to the DBR mirror region of the DBR laser to convert the wavelength of the output laser;
Supplying a compensation current to an optical gain region of the DBR laser to suppress a wavelength overshoot due to a carrier effect generated through a first supply current provided in the DBR mirror region
And transmitting the optical signal. 11. The method of claim 10,
Wherein the step of supplying the compensation current comprises:
And supplies a compensation current having an opposite sign to the first supply current to the optical gain region based on a wavelength switching time required by an application to which the DBR laser is applied. 11. The method of claim 10,
Wherein the step of supplying the compensation current comprises:
And adjusting the magnitude of the compensation current to be proportional to the magnitude of the first supply current. A wavelength tuning method of an optical transmitter including a temperature-independent DBR laser,
Providing a first supply current to the DBR mirror region of the DBR laser to convert the wavelength of the output laser;
Supplying a compensation current to the semiconductor optical amplifier to suppress wavelength drift due to a temperature effect generated through a first supply current provided in the DBR mirror region
And transmitting the optical signal. 14. The method of claim 13,
Supplying the compensation current,
And supplies a compensation current having an opposite sign to the first supply current to the semiconductor optical amplifier based on a wavelength holding time required by an application to which the DBR laser is applied. 14. The method of claim 13,
Supplying the compensation current,
And adjusting the magnitude of the compensation current to be proportional to the magnitude of the first supply current. A wavelength tuning method of an optical transmitter including a temperature-independent DBR laser,
Providing a first supply current to the DBR mirror region of the DBR laser to convert the wavelength of the output laser;
A first compensation current and a second compensation current are applied to the optical gain region and the semiconductor optical amplifier, respectively, in order to suppress wavelength drift due to a wavelength overshoot and a temperature effect due to a carrier effect generated through a first supply current provided to the DBR mirror region. 2 < / RTI >
And transmitting the optical signal. 17. The method of claim 16,
Wherein the supplying of the first compensation current and the second compensation current comprises:
Supplying a first compensation current having an opposite sign to the first supply current to the optical gain region based on a wavelength switching time required by an application to which the DBR laser is applied,
And supplies a second compensation current having an opposite sign to the first supply current to the semiconductor optical amplifier based on a wavelength holding time required by an application to which the DBR laser is applied. 17. The method of claim 16,
Wherein the supplying of the first compensation current and the second compensation current comprises:
And adjusting a magnitude of the first compensation current and the second compensation current so as to be proportional to the magnitude of the first supply current.

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