KR20210067953A - Optical transceiver - Google Patents

Abstract

According to one aspect of the present invention, disclosed is an optical transceiver which comprises: a reference tunable laser module that generates and outputs light of a reference wavelength; a first general tunable laser module for generating and outputting light of a first wavelength; and a controller for controlling a tuning operation of the first wavelength of the first general tunable laser module based on information on the relationship between the reference wavelength and the first wavelength. Therefore, the optical transceiver can reduce manufacturing costs.

Description

Optical transceiver {OPTICAL TRANSCEIVER}

The present disclosure relates to an optical transceiver, and more particularly, to a tunable optical transceiver.

Passive Optical Network (hereinafter referred to as 'PON') has become the core of the FTTH environment and Giga-bit Ethernet implementation.

In order to implement WDM-PON, a plurality of light sources with unique wavelengths are required. In order to implement a plurality of light sources having different wavelengths in the WDM-PON, the use of a multiport type tunable optical transceiver capable of simultaneously outputting a plurality of optical signals having different wavelengths is gradually increasing.

The above-described wavelength tunable optical transceiver includes a plurality of integrated tunable laser modules, wherein the integrated tunable laser modules typically have the same configuration and structure. For example, the tunable laser modules include a Wavelength Locker, an I/V Converter, a Thermistor, and a Thermoelectric Cooler (TEC), respectively. However, the Wavelength Locker, I/V Converter, Thermistor, TEC, and the like are not configured to generate light of a required wavelength (ie, an assigned wavelength) for the corresponding tunable laser module. Nevertheless, as they are all included in each tunable laser module, there arises a problem that the tunable optical transceiver is disadvantageous in terms of manufacturing cost, design and control complexity.

Korean Patent Publication No. 10-2009-0037195

In order to solve the above problems, the present disclosure provides a tunable optical transceiver capable of outputting light sources having a plurality of wavelengths while reducing manufacturing cost and design and control complexity.

The technical task to be achieved by the technical idea of the present disclosure is not limited to the tasks mentioned above, and another task not mentioned will be clearly understood by those skilled in the art from the following description.

According to an aspect of the present disclosure, a reference tunable laser module for generating and outputting light of a reference wavelength; a first general tunable laser module for generating and outputting light of a first wavelength; and a controller for controlling a tuning operation of the first wavelength of the first general tunable laser module based on information on the relationship between the reference wavelength and the first wavelength.

According to an exemplary embodiment, the information on the relationship between the reference wavelength and the first wavelength may be information indicating a difference between the reference wavelength and the first wavelength.

According to an exemplary embodiment, the difference between the reference wavelength and the first wavelength may be predetermined in consideration of a temperature-dependent correlation between the reference wavelength and the first wavelength.

According to an exemplary embodiment, the optical transceiver may further include a memory in which a lookup table including information on a relationship between the reference wavelength and the first wavelength is stored.

According to an exemplary embodiment, the reference wavelength may be a wavelength for a data transmission/reception channel or a wavelength for an auxiliary channel.

According to an exemplary embodiment, only the reference tunable laser module among the reference tunable laser module and the first general tunable laser module includes at least one of a wavelength fixer, a current-to-voltage converter, a thermoelectric cooler, and a temperature sensor. can

According to an exemplary embodiment, the optical transceiver further includes a second general tunable laser module for generating and outputting light of a second wavelength, wherein the controller is configured to control the relationship between the reference wavelength and the second wavelength. A tuning operation of the second wavelength of the second general tunable laser module may be controlled based on the information about the second wavelength.

According to another aspect of the present disclosure, at least one tunable laser module; and a controller for controlling wavelength tuning of the at least one tunable laser module by referring to a lookup table including relationship information between a preset reference wavelength and an output wavelength allocated to the at least one tunable laser module. An optical transceiver is disclosed.

According to an exemplary embodiment, the relationship information may be information indicating a difference between the preset reference wavelength and the allocated output wavelength.

According to an exemplary embodiment, the difference between the preset reference wavelength and the assigned output wavelength is

According to an exemplary embodiment, it may be determined in advance in consideration of a correlation according to a temperature between the preset reference wavelength and the assigned output wavelength.

According to an exemplary embodiment, the preset reference wavelength may be a wavelength for a data transmission/reception channel or a wavelength for an auxiliary channel.

According to an exemplary embodiment, the optical transceiver further includes a reference tunable laser module for generating and outputting light of the preset reference wavelength, but only the reference tunable laser module includes a wavelength fixer, a current voltage It may include at least one of a transducer, a thermoelectric cooler, and a temperature sensor.

According to embodiments of the present disclosure, in implementing a wavelength tunable optical transceiver capable of outputting light sources having a plurality of wavelengths by integrating a plurality of tunable laser modules, manufacturing costs are reduced by simplifying parts of some tunable laser modules. can be reduced, and design and control complexity can be reduced.

Effects that can be obtained in the embodiments according to the technical spirit of the present disclosure are not limited to the above-mentioned effects, and other effects not mentioned are common knowledge in the technical field to which the technical spirit of the present disclosure belongs from the description below. It can be clearly understood by those who have

In order to more fully understand the drawings recited in the Detailed Description of the present disclosure, a brief description of each drawing is provided.
1 is a configuration diagram of an optical communication system according to an embodiment of the present disclosure.
2 is a block diagram of an optical transceiver according to an embodiment of the present disclosure.
3 is a block diagram of a reference tunable laser module according to an embodiment of the present disclosure.
4 is a block diagram of a general tunable laser module according to an embodiment of the present disclosure.
5 is an exemplary diagram of a wavelength lookup table according to an embodiment of the present disclosure.

Since the technical spirit of the present disclosure may have various changes and may have various embodiments, specific embodiments will be illustrated in the drawings and described in detail. However, this is not intended to limit the technical spirit of the present disclosure to specific embodiments, and should be understood to include all changes, equivalents, or substitutes included in the scope of the technical spirit of the present disclosure.

In describing the technical idea of the present disclosure, if it is determined that a detailed description of a related known technology may unnecessarily obscure the spirit of the present disclosure, the detailed description thereof will be omitted. In addition, the numbers (eg, first, second, etc.) used in the description of the present application are only identifiers for distinguishing one component from other components.

In addition, in this specification, when an element is referred to as “connected” or “connected” to another element, the one element may be directly connected to or directly connected to the other element, but in particular the opposite is true. Unless there is a description to be used, it will be understood that it may be connected or connected through another element in the middle.

In addition, terms such as "~ unit", "~ group", "~ character", etc. described herein mean a unit for processing at least one function or operation, which is a processor, a microprocessor, Microcontroller, CPU (Central Processing Unit), GPU (Graphics Processing Unit), APU (Accelerate Processor Unit), DSP (Digital Signal Processor), ASIC (Application Specific Integrated Circuit), FPGA (Field Programmable Gate Array) It may be implemented in hardware, such as software, or a combination of hardware and software.

In addition, it is intended to clarify that the classification of the constituent parts in the present application is merely a classification for each main function that each constituent unit is responsible for. That is, two or more components to be described below may be combined into one component, or one component may be divided into two or more for each more subdivided function. In addition, each of the constituent units to be described below may additionally perform some or all of the functions of other constituent units in addition to the main function it is responsible for. Of course, it may be carried out by being dedicated to it.

Hereinafter, various embodiments according to the spirit of the present disclosure will be described in detail in turn.

1 is a configuration diagram of an optical communication system according to an embodiment of the present disclosure.

Referring to FIG. 1 , an optical communication system 100 according to an embodiment of the present disclosure includes an optical communication device 110 and a deMUX 120 that receives an optical signal transmitted from the optical communication device 110 , and a demux. It may include remote-side optical transceivers 130 that are connected to 120 and receive the separated individual optical signals.

The optical communication device 110 includes n optical transceivers 112-1 to 112-n (where n is a natural number greater than or equal to 2) and n optical transceivers 112-1 to 112-n that generate individual optical signals. It may include a mux 111 for muxing the n input optical signals. According to an embodiment, the mux 111 may be separated from the optical communication device 110 .

The optical communication device 110 may convert input data or data received from another device into an optical signal and transmit it to the demux 120 . In addition, the demux 120 is a device connected to the optical communication device 110 through an optical cable, and transmits individual optical signals allocated to each of the corresponding remote-side optical transceivers 130 . The remote-side optical transceivers 130 are coupled to a predetermined device.

In some embodiments, the optical communication system 10 may be applied to an optical subscriber network. In this case, the optical communication device 110 may be an optical line terminal (OLT) on the side of the central office. The remote location optical transceivers 130 may be connected to any one of a remote terminal (RT), an optical network terminal (ONT) on the subscriber side, and an optical network unit (Optical Network Unit).

In another embodiment, the optical communication system 100 may configure an optical transport network that is a sub-network constituting a fronthaul segment of a radio access network architecture. In this case, the optical communication device 110 may be a digital unit (Digital Unit, DU) or a baseband unit (BaseBand Unit, BBU) on the side of the central office (Central Office) side of the full-side termination device. In addition, the remote location optical transceivers 130 may be connected to remote units (RUs) or remote radio heads (RRHs). However, the present disclosure is not limited thereto, and the technical spirit of the present disclosure may be applied to a midhaul segment and a backhaul segment of the radio access network architecture.

In another embodiment, the optical communication system 100 may be applied to a Distributed Antenna System (DAS) for resolving a shadow area of a base station. In this case, the optical communication device 110 may be a headend unit, and the remote-side optical transceivers 130 may be connected to an extension unit or a remote unit.

As described above, the optical communication system 100 according to the technical spirit of the present disclosure is applicable to various optical communication networks implemented as optical communication devices that are located at remote locations from each other and transmit and receive optical signals through corresponding optical transceivers.

Hereinafter, specific operations of the components of the optical communication device 110 and, in particular, the optical transceiver 112 will be described with reference to FIGS. 2 to 5 .

2 is a block diagram of an optical transceiver 112 according to an embodiment of the present disclosure, and FIG. 3 is a block diagram of a reference tunable laser module 240 according to an embodiment of the present disclosure, FIG. 4 is a block diagram of a general tunable laser module 230 according to an embodiment of the present disclosure, and FIG. 5 is an exemplary diagram of a wavelength lookup table according to an embodiment of the present disclosure.

2 to 4, the optical transceiver 112 according to an embodiment of the present disclosure includes a controller (MCU, Main Control Unit) 210, a memory 220, and m general tunable laser modules 230- 1, 230-2 to 230-m) (where m is a natural number equal to or greater than 3), and a reference tunable laser module 240 . Depending on the implementation, the optical transceiver 112 may further include a mux 250 .

First, the reference tunable laser module 240 and the general tunable laser module 230 will be described.

Reference tunable laser module 240 according to an embodiment of the present disclosure is a temperature sensor (Temperature Sensor) 300, TEC (Thermo electric Cooler) 310, a wavelength locker (Wavelength Locker) 320, a laser controller 330 and a laser diode 340 . Also, although not shown, the reference tunable laser module 240 may further include an I/V converter capable of converting a current signal into a voltage signal corresponding thereto, a Thermistor whose resistance value is changed according to temperature, and the like. .

The general tunable laser modules 230 - 1 to 230 - m according to an embodiment of the present disclosure may include a laser controller 410 and a laser diode 420 . It can be seen that the general tunable laser module 230 does not include a Thermo electric Cooler (TEC), a Wavelength Locker, an I/V Converter, and a Thermistor, unlike the reference tunable laser module 240 .

The reference tunable laser module 240 may output an optical signal of a preset n-th wavelength λn. Hereinafter, the nth wavelength λn is referred to as a reference wavelength. The reference wavelength may be preset, and according to an embodiment, a wavelength for a data transmission/reception channel or a wavelength for an auxiliary channel (wavelength for wavelength locking, etc.) may be set as the reference wavelength. Since the operation of the reference tunable laser module 240 is substantially the same as that of the conventional tunable laser module, a detailed description thereof will be omitted.

The first general tunable laser module 230-1 may output an optical signal of the first wavelength λ1 under the control of the controller 210 . In addition, the second general tunable laser module 230 - 2 may output an optical signal of the second wavelength λ2 under the control of the controller 210 . Also, the mth general tunable laser module 230 - m may output an optical signal of an mth wavelength λm under the control of the controller 210 . Here, the first wavelength λ1 , the second wavelength λ2 to the mth wavelength λm, and the reference wavelength λn may all have different wavelengths.

More specifically, the controller 210 determines the optical signal output based on the relationship between the preset reference wavelength λn and the assigned wavelength required for each of the m individual general tunable laser modules 230-1 to 230-m. Describe the operation to be controlled.

First, information on the reference wavelength λn is stored in the memory 220, and information on the relationship between the reference wavelength λn and the first to mth wavelengths λ1 to λm is provided in the form of a lookup table. may be stored. Meanwhile, in FIG. 2 , the memory 220 is illustrated as a configuration separate from the controller 210 , but the memory 220 may be a configuration included in the controller 210 .

The controller 210 sends the first general tunable laser module 230-1 based on the information on the relationship between the reference wavelength λn and the first wavelength λ1 stored in the lookup table of the memory 220. The included laser controller 410 may be controlled, and the laser controller 410 may output a first optical signal corresponding to the first wavelength λ1 from the laser diode 420 .

In the same way, the controller 210 is included in the mth general tunable laser module 230-m based on the information on the relationship between the reference wavelength λn and the mth wavelength λm stored in the lookup table. The laser controller 410 may be controlled, and the laser controller 410 may output an mth optical signal corresponding to the mth wavelength λm from the laser diode 420 .

Referring to FIG. 5 , a wavelength lookup table according to an embodiment of the present disclosure is illustrated. The wavelength lookup table includes information on the relationship between the first wavelength (λ1) and the reference wavelength (λn), information on the relationship between the second wavelength (λ2) and the reference wavelength (λn), to the mth wavelength (λm) and the reference wavelength. Information about the relationship of (λn) may be included.

The information on the relationship between the wavelengths and the reference wavelength may be information indicating a difference between the wavelengths. For example, as shown in FIG. 5 , the first wavelength is greater than the reference wavelength by a (λ1=λn+a), the second wavelength is greater than the reference wavelength by b (λ2=λn+b), and the mth wavelength Information indicating that the wavelength is greater than the reference wavelength by k (λm=λn+k) may be included in the wavelength lookup table.

The difference (a, b, etc.) between the wavelengths may be, for example, a value predetermined in consideration of a correlation according to temperature, and the wavelength lookup table may also include information related to the temperature. For example, in the wavelength lookup table, a=αΔT+x1, b=αΔT+x2, and k=αΔT+xm may be preset. Here, α may be a preset correlation coefficient. Also, ΔT may be a difference value from a preset reference temperature. Information on the reference temperature may be stored in advance in the memory 220 , the reference tunable laser module 240 may sense the current temperature through the provided temperature sensor 300 , and the controller 210 senses A difference value (ΔT) between the measured temperature and the reference temperature can be generated. Also, x1 to xm may be preset offsets. Such temperature-related information may also be included in the wavelength lookup table and stored in advance in the memory 220 . Also, information on the size of the reference wavelength may be previously stored in the memory 220 .

Accordingly, the controller 210 reads information about the relationship between the reference wavelength stored in the memory 220 and the wavelength required for general tunable laser modules with reference to the wavelength lookup table, and based on the read information, the first The wavelength tuning of the optical signal may be controlled to have a wavelength required for each of the general tunable laser module 230 - 1 to the m th general tunable laser module 230 - m.

In other words, the controller 210 can control the laser controller 410 of each of the general tunable laser modules, and each laser controller 410 is set (or assigned) output light according to the control of the controller 210 . The output light wavelength value of a general laser diode can be set to have a wavelength value.

The n-th optical signal output from the reference tunable laser module 240 may be combined with transmission data in a corresponding modulator and converted into modulated n-th optical data to be input to the mux 250 . have.

Similarly, the first optical signal output from the first general tunable laser module 230 - 1 to the m th optical signal output from the m th general tunable laser module 230 are respectively transmitted data and The combined and modulated first optical data to m-th optical data may be converted, and each of the first optical data to m-th optical data may be input to the mux 250 .

The mux 250 of the optical transceiver 112 may mux (or multiplex) the first optical data to the n-th optical data and output the mux 111 of the optical communication device 110 . The mux 111 of the optical communication device 110 multiplexes the optical signals input from the plurality of optical transceivers 112-1 to 112-n to the corresponding remote-side optical transceiver ( 130) can be transmitted.

As described above, the controller 210 may set the wavelength value of the optical signal output from the general tunable laser modules 230 - 1 to 230 -m by using the wavelength lookup table stored in the memory 220 .

Due to this, each of the plurality of general tunable laser modules 230-1 to 230-m includes a laser controller 410 and a laser diode 420 for generating an optical signal and other components (eg, TEC, Wavelength). Locker, Thermistor, etc.) may not be included.

Due to this, it is apparent that the optical transceiver 110 according to the embodiments of the present disclosure may have a simple configuration and further reduce the manufacturing cost.

In the above description, it is assumed that the reference tunable laser module 240 outputs an optical signal of a preset reference wavelength, but the reference tunable laser module 240 also emits light having a corresponding wavelength under the control of the controller 210 . can be created and printed.

For example, the wavelength lookup table of the memory 220 may include information on the relationship between the reference wavelength and the wavelength to be output from the reference tunable laser module 240 (ie, the n-th wavelength). In this case, the controller 210 may tune the reference wavelength using information stored in the wavelength lookup table of the memory 220 . That is, the controller 210 may control the laser controller 330 , and the laser controller 330 may set the output light wavelength value of the reference laser diode 340 according to the control of the controller 210 .

In the above, the technical idea of the present disclosure has been described in detail with reference to various embodiments, but the technical idea of the present disclosure is not limited to the above embodiments, and those of ordinary skill in the art within the scope of the technical spirit of the present disclosure Various modifications and changes are possible by the person.

100: optical communication system
110: optical communication device
120: Demux
112, 130: optical transceiver

Claims (12)

a reference tunable laser module for generating and outputting light of a reference wavelength;
a first general tunable laser module generating and outputting light of a first wavelength; and
a controller for controlling a tuning operation of the first wavelength of the first general tunable laser module based on information on the relationship between the reference wavelength and the first wavelength;
comprising, an optical transceiver.
According to claim 1,
Information on the relationship between the reference wavelength and the first wavelength,
information indicative of a difference between the reference wavelength and the first wavelength.
3. The method of claim 2,
The difference between the reference wavelength and the first wavelength is
The optical transceiver is predetermined in consideration of a temperature-dependent correlation between the reference wavelength and the first wavelength.
According to claim 1,
a memory storing a lookup table including information on a relationship between the reference wavelength and the first wavelength;
Further comprising, an optical transceiver,
According to claim 1,
The reference wavelength is a wavelength for a data transmission/reception channel or a wavelength for an auxiliary channel.
According to claim 1,
Among the reference tunable laser module and the first general tunable laser module, only the reference tunable laser module includes at least one of a wavelength fixer, a current-to-voltage converter, a thermoelectric cooler, and a temperature sensor.
According to claim 1,
a second general tunable laser module generating and outputting light of a second wavelength;
further comprising,
wherein the controller controls a tuning operation of the second wavelength of the second general tunable laser module based on information on a relationship between the reference wavelength and the second wavelength.
at least one tunable laser module; and
a controller for controlling wavelength tuning of the at least one tunable laser module by referring to a lookup table including relationship information between a preset reference wavelength and an output wavelength allocated to the at least one tunable laser module;
Including, an optical transceiver.
9. The method of claim 8,
The relationship information is
information indicative of a difference between the preset reference wavelength and the assigned output wavelength.
10. The method of claim 9,
The difference between the preset reference wavelength and the assigned output wavelength is,
The optical transceiver is predetermined in consideration of a temperature-dependent correlation between the preset reference wavelength and the assigned output wavelength.
9. The method of claim 8,
The preset reference wavelength is a wavelength for a data transmission/reception channel or a wavelength for an auxiliary channel.
9. The method of claim 8,
a reference tunable laser module for generating and outputting light of the preset reference wavelength;
further comprising,
The optical transceiver, wherein only the reference tunable laser module includes at least one of a wavelength fixer, a current-to-voltage converter, a thermoelectric cooler, and a temperature sensor.

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