KR102582760B1 - Method for tuning wavelength of optical transceiver based on strength of optical signal and electronic device thereof - Google Patents

Abstract

A first optical transceiver according to an embodiment includes an optical transmission element module (transmitter optical sub-assembly, TOSA), an optical reception element module (receiver optical sub-assembly, ROSA), a wavelength adjustment module, and the optical transmission element module, Comprising: a controller operatively coupled to the light receiving device module and the wavelength adjustment module, wherein the controller determines the intensity of a plurality of optical signals corresponding to different wavelengths through the light receiving device module; Receive information indicating, identify the amount of change in intensity of the optical signal based on the received information, identify a wavelength that satisfies specified conditions based on the amount of change in intensity of the identified optical signal, and identify the wavelength at the identified wavelength. Based on this, the wavelength of the optical signal transmitted from the optical transmission device module may be adjusted. Other embodiments are also possible.

Description

Method for adjusting the wavelength of an optical transceiver based on the intensity of an optical signal and its electronic device {METHOD FOR TUNING WAVELENGTH OF OPTICAL TRANSCEIVER BASED ON STRENGTH OF OPTICAL SIGNAL AND ELECTRONIC DEVICE THEREOF}

The descriptions below relate to a method and electronic device for adjusting the wavelength of an optical transceiver based on the intensity of an optical signal.

In order to process more data at faster speeds, the proportion of optical communications within networks is increasing. As the proportion of optical communications increases, the demand for optical transceivers that perform conversion between electrical signals and optical signals is increasing.

Wavelength division multiplexing-passive optical network (WDM-PON) technology is a technology that uses optical signals of different wavelengths for each channel, and requires wavelength locking technology. Conventional optical transceivers can fix the wavelength of an optical signal through a separate hardware component (eg, a wavelength locker) for fixing the wavelength. This conventional wavelength fixing method uses separate hardware for wavelength fixing in an optical transceiver that transmits an optical signal, so the volume of the optical transceiver increases and the manufacturing cost is high. Therefore, a solution that can fix the wavelength of an optical signal while reducing the volume and manufacturing cost of the optical transceiver may be required.

A first optical transceiver according to an embodiment includes an optical transmitter optical sub-assembly (TOSA), a receiver optical sub-assembly (ROSA), a wavelength tuning module, and the optical transmitter module. and a controller operatively coupled to the device module, the light receiving device module, and the wavelength adjustment module, wherein the controller generates a plurality of lights corresponding to different wavelengths through the light receiving device module. Receiving information indicating the intensity of the signal, identifying the amount of change in intensity of the optical signal based on the received information, identifying a wavelength that satisfies specified conditions based on the amount of change in intensity of the identified optical signal, and identifying the It may be configured to adjust the wavelength of the optical signal transmitted from the optical transmission device module based on the wavelength.

A first optical transceiver according to an embodiment includes an optical transmission element module (transmitter optical sub-assembly, TOSA), an optical reception element module (receiver optical sub-assembly, ROSA), a wavelength adjustment module, and the optical transmission element module, and a controller operatively coupled to the light receiving element module and the wavelength adjustment module, wherein the controller transmits a plurality of optical signals corresponding to different wavelengths through the light receiving element module. Receive information indicating the intensity, generate reference data based on the information indicating the intensity of the plurality of optical signals, and adjust the wavelength of the optical signal transmitted through the optical transmission element module based on the reference data. It can be configured to do so.

A method for adjusting the wavelength of an optical transceiver and an electronic device thereof according to an embodiment adjust and fix the wavelength of an optical signal without using separate hardware for fixing the wavelength, thereby using separate hardware for fixing the wavelength. The volume and manufacturing cost of the optical transceiver can be lowered compared to when using this method.

1 illustrates an environment including electronic devices that perform data communication over an optical network.
FIG. 2A is a block diagram for explaining a first optical transceiver according to an embodiment.
FIG. 2B is a block diagram for explaining a second optical transceiver according to an embodiment.
FIG. 3 is a flowchart illustrating an example of a method for adjusting a wavelength in a first optical transceiver according to an embodiment.
FIGS. 4A and 4B are graphs illustrating an example of a method for adjusting a wavelength in a first optical transceiver according to an embodiment.
FIG. 5 is a flowchart illustrating another example of a method for adjusting a wavelength in a first optical transceiver according to an embodiment.
FIG. 6 is a graph illustrating another example of a method for adjusting a wavelength in a first optical transceiver according to an embodiment.
FIG. 7 is a flowchart illustrating a method of generating feedback information in a second optical transceiver according to an embodiment.

Specific structural or functional descriptions of the embodiments according to the concept of the present invention disclosed in this specification are merely illustrative for the purpose of explaining the embodiments according to the concept of the present invention. They may be implemented in various forms and are not limited to the embodiments described herein.

Since the embodiments according to the concept of the present invention can make various changes and have various forms, the embodiments will be illustrated in the drawings and described in detail in this specification. However, this is not intended to limit the embodiments according to the concept of the present invention to specific disclosed forms, and includes changes, equivalents, or substitutes included in the spirit and technical scope of the present invention.

Terms such as first or second may be used to describe various components, but the components should not be limited by the terms. The above terms are used only for the purpose of distinguishing one component from another component, for example, a first component may be named a second component, without departing from the scope of rights according to the concept of the present invention, Similarly, the second component may also be referred to as the first component.

When a component is said to be "connected" or "connected" to another component, it is understood that it may be directly connected to or connected to the other component, but that other components may exist in between. It should be. On the other hand, when it is mentioned that a component is “directly connected” or “directly connected” to another component, it should be understood that there are no other components in between. Expressions that describe the relationship between components, such as “between”, “immediately between” or “directly adjacent to”, should be interpreted similarly.

The terminology used herein is only used to describe specific embodiments and is not intended to limit the invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, terms such as "comprise" or "have" are intended to designate the presence of implemented features, numbers, steps, operations, components, parts, or combinations thereof, and are intended to indicate the presence of one or more other features or numbers, It should be understood that this does not exclude in advance the possibility of the presence or addition of steps, operations, components, parts, or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the technical field to which the present invention pertains. Terms as defined in commonly used dictionaries should be interpreted as having meanings consistent with the meanings they have in the context of the related technology, and unless clearly defined in this specification, should not be interpreted in an idealized or overly formal sense. No.

Hereinafter, embodiments will be described in detail with reference to the attached drawings. However, the scope of the patent application is not limited or limited by these examples. The same reference numerals in each drawing indicate the same members.

1 illustrates an environment including electronic devices that perform data communication over an optical network.

According to one embodiment, the optical network of FIG. 1 may include an optical network in which electronic devices deployed in different regions are connected based on one or more optical lines 130. Optical networks may include, for example, Passive Optical Networks (PONs).

Referring to FIG. 1, a first electronic device (e.g., digital unit (DU) or central office terminal (COT)) 110 and a second electronic device (e.g., radio unit (RU), RRH ( An example in which a remote radio head (or remote radio unit (RRU)) 150 is connected based on an optical line 130 is shown. The optical network including the first electronic device 110 and the second electronic device 150 may, for example, correspond to at least a portion of a 5G fronthaul. However, it is not limited to this. For example, an optical line terminal (OLT) and/or an optical network unit (ONU) may be connected to each other based on the optical line 130.

According to one embodiment, the first electronic device 110 and/or the second electronic device 150 may include one or more electronic devices according to various embodiments. For example, the first electronic device 110 includes k first optical transceivers 101-1, ..., 101-k, and the second electronic device 150 includes k second optical transceivers. It may include (101-k+1, ..., 101-2k).

According to one embodiment, the first optical transceiver (101-1, ..., or 101-k) is an electrical device to support the transmission and/or reception of electrical signals, to perform conversion between optical signals and electrical signals. It may include an interface 115 and an optical interface 125 to support transmission and/or reception of optical signals. Electrical interface 115 may include one or more pins, electrodes, and/or wires transmissible for electrical signals based on a designated communication protocol, such as the I2C protocol, for example. Optical interface 125 may include, for example, one or more optical ports for connecting to one or more optical fibers.

According to one embodiment, the first optical transceiver (101-1, ..., or 101-k) is connected to a first multiplexer and demultiplexer device (MUX/DEMUX device) included in the optical network through the optical interface 125. It can be connected to (120). The first multiplexer and demultiplexer device 120 performs optical multiplexing and/or demultiplexing based on a thin film filter (TFF), and may have a passband allocated to each access port. Optical ports extending from the first multiplexer and demultiplexer device 120 may transmit and receive optical signals of different wavelengths.

According to one embodiment, the second optical transceiver (101-k+1, ..., or 101-2k) supports transmission and/or transmission of electrical signals, to perform conversion between optical signals and electrical signals. It may include an electrical interface 155 for and an optical interface 145 for supporting transmission and/or reception of optical signals. Electrical interface 155 may include one or more pins, electrodes, and/or wires transmissible for electrical signals based on a designated communication protocol, such as the I2C protocol, for example. Optical interface 145 may include, for example, one or more optical ports for connecting to one or more optical fibers.

According to one embodiment, the second optical transceiver (101-k+1, ..., or 101-2k) is connected to the second multiplexer and demultiplexer device (MUX/DEMUX) included in the optical network through the optical interface 145. device) (140). The second multiplexer and demultiplexer device 140 performs optical multiplexing and/or demultiplexing based on a thin film filter, and may have a passband allocated to each access port. Optical ports extending from the second multiplexer and demultiplexer device 140 may transmit and receive optical signals of different wavelengths.

According to one embodiment, the first and second multiplexer and demultiplexer devices 120 and 140 may change the path through which an optical signal propagates within an optical network based on wavelength division multiplexing (WDM). . For example, a plurality of optical signals having different wavelengths transmitted by a plurality of first optical transceivers 101-1, ..., 101-k are multiplexed in the first multiplexer and demultiplexer device 120. It may propagate along the optical line 130. The multiplexed optical signals may be demultiplexed in the second multiplexer and demultiplexer device 140 and distributed to a plurality of second optical transceivers 101-k+1, ..., 101-2k. For another example, a plurality of optical signals having different wavelengths transmitted by a plurality of second optical transceivers (101-k+1, ..., 101-2k) are transmitted by the second multiplexer and demultiplexer device 140. It can be multiplexed and propagated along the optical line 130. The multiplexed optical signals may be demultiplexed in the first multiplexer and demultiplexer device 120 and distributed to a plurality of first optical transceivers 101-1, ..., 101-k.

FIG. 2A is a block diagram for explaining a first optical transceiver according to an embodiment. Hereinafter, a module, unit, and/or circuit may refer to a set of one or more circuit elements of the first optical transceiver and the second optical transceiver of FIGS. 2A to 2B.

Referring to FIG. 2A, the first optical transceiver 200 includes a controller 210, a wavelength adjustment module 211, an optical transmission element module (transmitter optical sub-assembly, TOSA) 220, and an optical reception element module (receiver). It may include an optical sub-assembly (ROSA) 230, a first amplifier 231, a second amplifier 233, and a connector 240. However, it is not limited to this. For example, the first optical transceiver 200 may further include other components in addition to the components described above.

According to one embodiment, the controller 210 may process data based on one or more instructions. The controller 210 may include, for example, an Arithmetic and Logic Unit (ALU), a Field Programmable Gate Array (FPGA), and/or a Central Processing Unit (CPU).

According to one embodiment, the controller 210 may include a memory for storing input and/or output data and/or instructions. The memory may be included in the controller 210 in the form of a system-on-chip (SoC), or may be placed on a printed circuit board (PCB) of the first optical transceiver 200 together with the controller 210. Memory may include, for example, volatile memory such as random-access memory (RAM) and/or non-volatile memory such as read-only memory (ROM). Volatile memory may include, for example, at least one of Dynamic RAM (DRAM), Static RAM (SRAM), Cache RAM, and Pseudo SRAM (PSRAM). Non-volatile memory may include, for example, at least one of PROM (Programmable ROM), EPROM (Erasable PROM), EEPROM (Electrically Erasable PROM), flash memory, hard disk, compact disk, and eMMC (Embedded Multi Media Card). You can.

According to one embodiment, the optical transmission device module 220 may output an optical signal based on a control signal from the controller 210. The optical transmission device module 220 may include a laser diode (LD) for generating an optical signal. Laser diodes include, for example, fabric perot LD (FP-LD), distributed feedback LD (DFB-LD), distributed bragg reflector LD (DBR-LD), external cavity laser (ECL), and/or vertical cavity laser (VCSEL). surface emitting laser). According to one embodiment, the laser diode may include a tunable laser diode (tunable LD) in which the wavelength of the output optical signal is adjusted based on voltage, current, and/or temperature. According to one embodiment, the control signal transmitted from the controller 210 may be amplified through the first amplifier 231 and then provided to the optical transmission device module 220.

According to one embodiment, the wavelength adjustment module 211 may adjust the wavelength of the optical signal output from the optical transmission device module 220 based on the control signal of the controller 210. For example, the wavelength adjustment module 211 adjusts the amplitude and/or frequency of the voltage and/or current input to the optical transmission device module 220, thereby adjusting the output from the optical transmission device module 220. The wavelength of the optical signal can be adjusted. In this case, the wavelength adjustment module 211 may include an oscillator and/or a modulator. For another example, the wavelength adjustment module 211 may adjust the wavelength of the optical signal output from the optical transmission module 220 by adjusting the temperature of the optical transmission element module 220. In this case, the wavelength adjustment module 211 may include a temperature sensor (thermistor) and/or a thermo-electric cooler (TEC). According to one embodiment, the wavelength adjustment module 211 may adjust the wavelength of the optical transmission element module 220 to a value smaller than the wavelength section where the intensity of the optical signal becomes constant (or maximum).

According to one embodiment, the light receiving element module 230 may receive an optical signal provided from an optical network. The optical receiving device module 230 may output an electrical signal corresponding to the received optical signal. The electrical signal output from the light receiving element module 230 may be amplified through the second amplifier 233 and then provided to the controller 210 and the connector 240. According to one embodiment, the light receiving device module 230 may include a photodiode (PD) to output an electrical signal corresponding to an optical signal. Photodiodes may include, for example, PIN-PD (P-I-N PD) and APD (avalanche PD).

According to one embodiment, the connector 240 is an electrical interface (e.g., the electrical interface 115 of FIG. 1), which is connected to the first optical transceiver 200 and another electronic device (e.g., the first electronic device 110 of FIG. 1). )) can support electrical coupling between

According to one embodiment, the controller 210 may transmit a plurality of optical signals corresponding to different wavelengths through the optical transmission device module 220. For example, the controller 210 transmits a first optical signal of a first wavelength through the optical transmission device module 220 and, after a designated time, transmits a first optical signal different from the first wavelength through the optical transmission device module 220. A second optical signal of two wavelengths may be transmitted, and after a designated time, a third optical signal of a third wavelength different from the first and second wavelengths may be transmitted through the optical transmission device module 220.

According to one embodiment, the controller 210 may receive information indicating the intensity of the optical signal through the light receiving element module 230. For example, the controller 210 receives light from a second optical transceiver (e.g., the second optical transceiver 101-k+1, ..., or 101-2k in FIG. 1) through the optical receiving element module 230. When a signal is received, a subcarrier signal can be obtained from the optical signal using a filter (e.g., a low pass filter). The controller 210 demodulates the subcarrier signal to obtain an optical signal (e.g., the first Information indicating the intensity of the optical signal, the second optical signal, and/or the third optical signal may be obtained.

According to one embodiment, the controller 210 may identify the amount of change in the intensity of the optical signal based on information indicating the intensity of the plurality of optical signals. For example, the controller 210 may identify the amount of change in the intensity of the optical signal based on information indicating the intensity of the plurality of optical signals. Specifically, the controller 210 identifies the amount of change in the intensity of the first optical signal and the second optical signal based on the information indicating the intensity of the first optical signal and the information indicating the intensity of the second optical signal, and The amount of change in intensity of the second optical signal and the third optical signal can be identified based on the information indicating the intensity of the optical signal and the information indicating the intensity of the third optical signal.

According to one embodiment, the controller 210 may identify a wavelength that satisfies a specified condition in response to identifying the amount of change in intensity of the optical signal. By continuously monitoring the amount of change in the intensity of the optical signal, the controller 210 changes the wavelength corresponding to the point where the intensity of the optical signal is flat (or the first point where the intensity of the optical signal has the maximum value) to a wavelength that satisfies specified conditions. You can decide. For example, when the intensity change amount of the first optical signal and the second optical signal is greater than the reference change amount and the intensity change amount of the second optical signal and the third optical signal is less than the reference change amount, the controller 210 controls the By determining that the signal intensity is constant, the second wavelength can be determined as a wavelength that satisfies specified conditions. If a wavelength that satisfies the specified conditions is not identified (or a section with a constant intensity of the optical signal is not identified), the controller 210 adjusts the wavelength and then transmits a plurality of optical signals of different wavelengths. You can re-perform the action.

According to one embodiment, the controller 210 may adjust the wavelength of the optical transmission device module 220 in response to determining the designated wavelength. For example, the controller 210 obtains a fourth wavelength by applying a specified value to a wavelength that satisfies specified conditions, and adjusts the wavelength so that the wavelength of the optical signal output from the optical transmission element module 220 is the fourth wavelength. The module 211 can be controlled.

According to one embodiment, the controller 210 may generate reference data based on information indicating the intensity of a plurality of optical signals. For example, the controller 210 loads intensity information of an optical signal according to a pre-stored wavelength from a memory (not shown), and based on information indicating the intensity of a plurality of optical signals, the By correcting the information, reference data can be obtained. For another example, the controller 210 may generate reference data by generating intensity information of the optical signal according to the wavelength from information indicating the intensity of the optical signal using interpolation. According to one embodiment, the reference data may include the parameters shown in <Table 1> below.

TEC temperature setting value Data matching wavelength information according to TEC temperature TEC temperature range value TEC temperature variable interval when finding the central wavelength Target channel center wavelength Center wavelength of target channel Received optical input intensity (or power) intensity of optical signal TEC temperature range value TEC temperature variable interval when finding the central wavelength Received optical input intensity (or intensity) slope Slope values of two wavelength points

According to one embodiment, the controller 210 may adjust the wavelength of the optical signal output through the optical transmission device module 220 based on reference data. For example, the controller 210 may identify a section where the intensity of the optical signal is maximum based on reference data. The controller 210 controls the optical transmission device module 220 through the wavelength adjustment module 211 so that the intensity of the optical signal output through the optical transmission device module 220 is within the section where the intensity of the optical signal is maximum. ), the wavelength of the output optical signal can be adjusted.

As described above, the first optical transceiver 200 adjusts the wavelength of the optical signal output from the first optical transceiver 200 based on the feedback information of the second optical transceiver so that the intensity of the optical signal has the highest value. It can be adjusted. When the intensity of the optical signal is at its maximum value, information indicating a change in intensity is not received by the first optical transceiver 200, and accordingly, the wavelength of the first optical transceiver 200 may be fixed. The above-described first optical transceiver 200 is configured to monitor the wavelength of the optical signal output through the optical transmission device module 220 without separate hardware for monitoring the wavelength of the optical signal output through the optical transmission device module 220. Since it adjusts and fixes, it has a smaller volume than an optical transceiver that uses separate hardware to monitor the wavelength of the optical signal output through the optical transmission element module 220, and the production cost can be lowered by saving hardware costs. .

FIG. 2B is a block diagram for explaining a second optical transceiver according to an embodiment.

Referring to FIG. 2B, the second optical transceiver 250 includes a controller 251, an optical intensity detection module 253, an optical transmission device module 260, an optical reception device module 270, and a first amplifier 271. , a second amplifier 273, and a connector 280. However, it is not limited to this. For example, the second optical transceiver 250 may further include other components in addition to the components described above.

According to one embodiment, the controller 251 may process data based on one or more instructions. The controller 251 may include, for example, an Arithmetic and Logic Unit (ALU), a Field Programmable Gate Array (FPGA), and/or a Central Processing Unit (CPU).

According to one embodiment, the controller 251 may include a memory for storing input and/or output data and/or instructions. The memory may be included in the controller 251 in the form of a system-on-chip (SoC), or may be placed on a printed circuit board (PCB) of the second optical transceiver 250 together with the controller 251. Memory may include, for example, volatile memory such as random-access memory (RAM) and/or non-volatile memory such as read-only memory (ROM). Volatile memory may include, for example, at least one of Dynamic RAM (DRAM), Static RAM (SRAM), Cache RAM, and Pseudo SRAM (PSRAM). Non-volatile memory may include, for example, at least one of PROM (Programmable ROM), EPROM (Erasable PROM), EEPROM (Electrically Erasable PROM), flash memory, hard disk, compact disk, and eMMC (Embedded Multi Media Card). You can.

According to one embodiment, the light intensity detection module 253 may detect (or identify) the intensity of an optical signal received through the light receiving element module 270. The light intensity detection module 253 may include, for example, a photodiode (PD) to output an electrical signal corresponding to the intensity of the light signal. The light intensity detection module 253 may output an electrical signal corresponding to the intensity of the light signal to the controller 210. According to one embodiment, the light intensity detection module 253 may be included in the controller 251 when implemented in hardware.

According to one embodiment, the optical transmission device module 260 may output an optical signal based on a control signal from the controller 210. The optical transmission device module 260 may include a laser diode (LD) for generating an optical signal. Laser diodes include, for example, fabric perot LD (FP-LD), distributed feedback LD (DFB-LD), distributed bragg reflector LD (DBR-LD), external cavity laser (ECL), and/or vertical cavity laser (VCSEL). surface emitting laser). According to one embodiment, the laser diode may include a tunable laser diode (tunable LD) in which the wavelength of the output optical signal is adjusted based on voltage, current, and/or temperature. According to one embodiment, the control signal transmitted from the controller 251 may be amplified through the first amplifier 271 and then provided to the optical transmission device module 260.

According to one embodiment, the optical receiving device module 270 may receive an optical signal provided from an optical network. The optical receiving device module 270 may output an electrical signal corresponding to the received optical signal. The electrical signal output from the light receiving element module 270 may be amplified through the second amplifier 273 and then provided to the controller 251 and the connector 280. According to one embodiment, the light receiving device module 270 may include a photodiode (PD) to output an electrical signal corresponding to an optical signal. Photodiodes may include, for example, PIN-PD (P-I-N PD) and APD (avalanche PD).

According to one embodiment, the connector 280 is an electrical interface (e.g., the electrical interface 155 of FIG. 1), which is connected to the second optical transceiver 250 and another electronic device (e.g., the second electronic device 150 of FIG. 1). )) can support electrical coupling between

According to one embodiment, when an optical signal is received by the optical receiving element module 270, the controller 251 may detect (or identify) the intensity of the optical signal. For example, when the controller 251 receives the first optical signal of the first wavelength from the first optical transceiver 200 through the optical receiving element module 270, the controller 251 detects the first optical signal through the optical intensity detection module 253. The strength of the signal can be identified. For another example, when the controller 251 receives the second optical signal of the second wavelength from the first optical transceiver 200 through the optical receiving element module 270, the controller 251 detects the second optical signal through the optical intensity detection module 253. The intensity of the optical signal can be identified. For another example, when the controller 251 receives the third optical signal of the third wavelength from the first optical transceiver 200 through the optical receiving element module 270, the controller 251 detects the third optical signal through the optical intensity detection module 253. 3 The intensity of optical signals can be identified.

According to one embodiment, the controller 251 may transmit information indicating the strength of the optical signal to the first optical transceiver 200 through the optical transmission device module 260. For example, in response to receiving the first optical signal (or second optical signal, or third optical signal) from the first optical transceiver 200, the controller 251 transmits the first optical signal (or second optical signal) Generates information indicating the strength of an optical signal (or a third optical signal), modulates it with a subcarrier (or low-frequency subcarrier) different from the carrier that modulates communication data, and transmits an optical signal combining the carrier and subcarrier. It can be transmitted to the first optical transceiver 200 through the device module 260. In this case, the controller 251 may use a frequency shift keying (FSK) modulation method. However, the modulation method performed by the controller 251 is not limited to the FSK method, and other modulation methods may be used.

As described above, the second optical transceiver 250 may provide feedback information to the first optical transceiver 200 so that the intensity of the optical signal of the first optical transceiver 200 has the highest value. Accordingly, the first optical transceiver 200 can adjust and fix the wavelength of the optical signal without separate hardware for monitoring the wavelength of the optical signal.

FIG. 3 is a flowchart illustrating an example of a method for adjusting a wavelength in a first optical transceiver according to an embodiment. FIGS. 4A and 4B are graphs illustrating an example of a method for adjusting a wavelength in a first optical transceiver according to an embodiment.

3 to 4B, in operation 301, a first optical transceiver (the first optical transceiver 101-1, ..., or 101-k of FIG. 1 or the first optical transceiver 200 of FIG. 2A) ) can receive information indicating the intensity of a plurality of optical signals corresponding to different wavelengths. For example, the first optical transceiver 200 transmits the first optical signal of the first wavelength to the second optical transceiver (e.g., the second optical transceiver of FIG. 1 ((101-k+1), ..., or ( 101-2k)) or the second optical transceiver 250 of FIG. 2B), and information indicating the strength of the first optical signal may be received from the second optical transceiver. After transmitting the first optical signal, the first optical transceiver 200 transmits a second optical signal of a second wavelength to the second optical transceiver 250, and transmits the second optical signal from the second optical transceiver 250. Information indicating the strength of can be received. After transmitting the second optical signal, the first optical transceiver 200 transmits the third optical signal of the third wavelength to the second optical transceiver 250, and transmits the third optical signal of the third wavelength from the second optical transceiver 250. Information indicating the intensity can be received. For another example, the first optical transceiver 200 sequentially transmits a first optical signal of a first wavelength, a second optical signal of a second wavelength, and a third optical signal of a third wavelength to the second optical transceiver 250 and receive information indicating the strength of the first optical signal, information indicating the strength of the second optical signal, and information indicating the strength of the third optical signal from the second optical transceiver 250. . Here, the first wavelength, second wavelength, and third wavelength may have different values. According to one embodiment, the first optical transceiver 200 obtains a subcarrier signal from the optical signal received from the second optical transceiver 250 using a filter, and demodulates the obtained subcarrier signal to strengthen the optical signal. Information indicating can be obtained.

In operation 303, the first optical transceiver 200 may identify the amount of change in intensity of the optical signal based on the received information. For example, as shown in FIG. 4A, the first optical transceiver 200 provides information indicating the intensity (pl1) of the first optical signal of the first wavelength (w1) and the second optical signal of the second wavelength (w2). Based on the information indicating the intensity pl2, a difference between the intensity pl1 of the first optical signal and the intensity pl2 of the second optical signal is identified, and the intensity of the second optical signal at the second wavelength w2 The intensity (pl2) of the second optical signal and the intensity (pl3) of the third optical signal based on the information indicating (pl2) and the information indicating the intensity (pl3) of the third optical signal of the third wavelength (w3) By identifying the difference between the two, the amount of change in the intensity of the optical signal can be identified.

In operation 305, the first optical transceiver 200 may identify a wavelength that satisfies a specified condition based on the amount of change in intensity of the optical signal. The first optical transceiver 200 continuously monitors the amount of change in the intensity of the optical signal, so that the wavelength corresponding to the point where the intensity of the optical signal is flat (or the first point where the intensity of the optical signal has the maximum value) satisfies a specified condition. It can be determined by the wavelength. For example, as shown in FIG. 4A, the first optical transceiver 200 provides an intensity change (or slope) (a1) of the optical signal of the k-1th wavelength (wk-1) and the optical signal of the k-th wavelength (wk). It is more than this reference change amount (or reference slope), and the intensity change amount (or slope (a2)) of the optical signal at the kth wavelength (wk) and the k+1th wavelength (wk+1) is the reference change amount (or reference slope). ), the kth wavelength (wk) can be determined as a wavelength that satisfies the specified conditions.

In operation 307, the first optical transceiver 200 may adjust the wavelength of the optical signal output through the first optical transceiver 200 based on the identified wavelength. For example, the first optical transceiver 200 obtains the fourth wavelength by applying a specified value to the wavelength that satisfies the specified condition, and changes the wavelength of the optical signal output from the first optical transceiver 200 to the fourth wavelength. can be adjusted. According to one embodiment, the first optical transceiver 200 may determine a designated value for obtaining the fourth wavelength based on the wavelength that satisfies the designated condition. For example, as shown in the graph 410 of FIG. 4B, when the kth wavelength (wk), which is shorter than the center wavelength, is determined to be a wavelength that satisfies a specified condition, the first optical transceiver 200 ) is the wavelength (wk+α) obtained by applying the first value (α) to the kth wavelength (wk) (or longer than the kth wavelength (wk) by the first value (α) It can be adjusted. For another example, as shown in the graph 420 of FIG. 4B, when the n-th wavelength (wn), which is longer than the center wavelength, is determined to be a wavelength that satisfies a specified condition, the first optical transceiver 200 is the first optical transceiver ( The wavelength of the optical signal output from 200) is a wavelength (wn-β) obtained by applying a second value (β) to the n-th wavelength (wn) (or shorter by a second value (β) than the n-th wavelength (wn)) can be adjusted. According to one embodiment, while the first optical transceiver 200 transmits an optical signal to the second optical transceiver 250, information (or feedback) indicating the strength of the optical signal received from the second optical transceiver 250 The operation of adjusting the wavelength of the optical signal transmitted to the second optical transceiver 200 based on the information) can be continuously performed.

As described above, the first optical transceiver 200 may adjust the wavelength of the optical signal based on feedback information (eg, information indicating the intensity of a plurality of optical signals) of the second optical transceiver 250. Since this first optical transceiver 200 adjusts and fixes the wavelength of the optical signal without separate hardware for monitoring the wavelength of the optical signal, it is smaller than the optical transceiver that uses separate hardware for monitoring the wavelength of the optical signal. It is bulky and can lower production costs by saving hardware costs.

FIG. 5 is a flowchart illustrating another example of a method for adjusting a wavelength in a first optical transceiver according to an embodiment. FIG. 6 is a graph illustrating another example of a method for adjusting a wavelength in a first optical transceiver according to an embodiment.

5 and 6, in operation 501, a first optical transceiver (the first optical transceiver 101-1, ..., or 101-k of FIG. 1 or the first optical transceiver 200 of FIG. 2A) ) can receive information indicating the intensity of a plurality of optical signals corresponding to different wavelengths. For example, the first optical transceiver 200 transmits the first optical signal of the first wavelength to the second optical transceiver (e.g., the second optical transceiver of FIG. 1 ((101-k+1), ..., or ( 101-2k)) or the second optical transceiver 250 of FIG. 2B), and information indicating the strength of the first optical signal may be received from the second optical transceiver. After transmitting the first optical signal, the first optical transceiver 200 transmits a second optical signal of a second wavelength to the second optical transceiver 250, and transmits the second optical signal from the second optical transceiver 250. Information indicating the strength of can be received. After transmitting the second optical signal, the first optical transceiver 200 transmits the third optical signal of the third wavelength to the second optical transceiver 250, and transmits the third optical signal of the third wavelength from the second optical transceiver 250. Information indicating the intensity can be received. For another example, the first optical transceiver 200 sequentially transmits a first optical signal of a first wavelength, a second optical signal of a second wavelength, and a third optical signal of a third wavelength to the second optical transceiver 250 and receive information indicating the strength of the first optical signal, information indicating the strength of the second optical signal, and information indicating the strength of the third optical signal from the second optical transceiver 250. . Here, the first wavelength, second wavelength, and third wavelength may have different values. According to one embodiment, the first optical transceiver 200 obtains a subcarrier signal from the optical signal received from the second optical transceiver 250 using a filter, and demodulates the obtained subcarrier signal to strengthen the optical signal. Information indicating can be obtained.

In operation 503, the first optical transceiver 200 may generate reference data based on information indicating the intensity of a plurality of optical signals. For example, the controller 210 uses interpolation to obtain intensity information of the optical signal depending on the wavelength from information indicating the intensity of the optical signal (e.g., the graph 610 in FIG. 6). By creating a graph 620, reference data can be generated. For another example, the first optical transceiver 200 loads intensity information of optical signals according to pre-stored wavelengths and provides information indicating the intensity of a plurality of optical signals (e.g., graph 610 of FIG. 6). ) Based on this, reference data can be obtained by correcting information loaded from memory.

In operation 505, the first optical transceiver 200 may adjust the wavelength of the optical signal based on reference data. For example, the first optical transceiver 200 has a wavelength section (wi) where the intensity of the optical signal is maximum, as shown in the graph 620 of FIG. 6. The wavelength of the optical signal output from the first optical transceiver 200 can be adjusted to be included in .

As described above, the first optical transceiver 200 continuously adjusts the intensity of the optical signal output through the first optical transceiver 200 based on the information (or feedback information) provided from the second optical transceiver 250. , and the wavelength of the optical signal output through the first optical transceiver 200 can be adjusted in real time based on the monitoring results. Since this first optical transceiver 200 adjusts and fixes the wavelength of the optical signal without separate hardware for monitoring the wavelength of the optical signal, it is smaller than the optical transceiver that uses separate hardware for monitoring the wavelength of the optical signal. It is bulky and can lower production costs by saving hardware costs.

FIG. 7 is a flowchart illustrating a method of generating feedback information in a second optical transceiver according to an embodiment.

Referring to FIG. 7, in operation 701, a second optical transceiver (e.g., the second optical transceiver 101-k+1, ..., 101-2k of FIG. 1 or the second optical transceiver 250 of FIG. 2B) ) can receive optical signals. For example, the second optical transceiver 250 is a first optical transceiver (e.g., the first optical transceiver 101-1, ..., 101-k in FIG. 1 or the first optical transceiver 200 in FIG. 2A). ) may receive a first optical signal of a first wavelength (or a second optical signal of a second wavelength, or a third optical signal of a third wavelength).

At operation 703, the second optical transceiver 250 may identify the strength of the received optical signal. For example, the second optical transceiver 250 may identify the intensity of the first optical signal of the first wavelength.

In operation 705, the second optical transceiver 250 may transmit information indicating the strength of the optical signal. For example, the second optical transceiver 250 generates information indicating the strength of the first optical signal, modulates the generated information into a subcarrier (or a low-frequency subcarrier) different from the carrier that modulates communication data, An optical signal combining a carrier wave and a subcarrier can be transmitted to the first optical transceiver 200.

In the above, the second optical transceiver 250 has been described as identifying the intensity of an optical signal of a specific wavelength and transmitting information indicating the intensity of the optical signal. However, the second optical transceiver 250 according to one embodiment For a certain period of time, the intensity of a plurality of optical signals having different wavelengths may be identified, and information indicating the intensity of each of the plurality of optical signals may be transmitted to the first optical transceiver 200.

As described above, the second optical transceiver 250 may generate feedback information for adjusting and/or fixing the wavelength of the first optical transceiver 200 and provide it to the first optical transceiver 200.

The device described above may be implemented with hardware components, software components, and/or a combination of hardware components and software components. For example, devices and components described in embodiments may include, for example, a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable gate array (FPGA), etc. , may be implemented using one or more general-purpose or special-purpose computers, such as a programmable logic unit (PLU), a microprocessor, or any other device capable of executing and responding to instructions. A processing device may execute an operating system (OS) and one or more software applications that run on the operating system. Additionally, a processing device may access, store, manipulate, process, and generate data in response to the execution of software. For ease of understanding, a single processing device may be described as being used; however, those skilled in the art will understand that a processing device includes multiple processing elements and/or multiple types of processing elements. It can be seen that it may include. For example, a processing device may include multiple processors or one processor and one controller. Additionally, other processing configurations, such as parallel processors, are possible.

Software may include a computer program, code, instructions, or a combination of one or more of these, which may configure a processing unit to operate as desired, or may be processed independently or collectively. You can command the device. Software and/or data may be used on any type of machine, component, physical device, virtual equipment, computer storage medium or device to be interpreted by or to provide instructions or data to a processing device. , or may be permanently or temporarily embodied in a transmitted signal wave. Software may be distributed over networked computer systems and stored or executed in a distributed manner. Software and data may be stored on one or more computer-readable recording media.

The method according to the embodiment may be implemented in the form of program instructions that can be executed through various computer means and recorded on a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, etc., singly or in combination. Program instructions recorded on the medium may be specially designed and configured for the embodiment or may be known and available to those skilled in the art of computer software. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks, and magnetic tapes, optical media such as CD-ROMs and DVDs, and magnetic media such as floptical disks. -Includes optical media (magneto-optical media) and hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, flash memory, etc. Examples of program instructions include machine language code, such as that produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter, etc.

The term “module” used in various embodiments of this document may include a unit implemented in hardware, software, or firmware, and is interchangeable with terms such as logic, logic block, component, or circuit, for example. It can be used as A module may be an integrated part or a minimum unit of the parts or a part thereof that performs one or more functions.

As described above, although the embodiments have been described with limited examples and drawings, various modifications and variations can be made by those skilled in the art from the above description. For example, the described techniques are performed in a different order than the described method, and/or components of the described system, structure, device, circuit, etc. are combined or combined in a different form than the described method, or other components are used. Alternatively, appropriate results may be achieved even if substituted or substituted by an equivalent.

Therefore, other implementations, other embodiments, and equivalents of the claims also fall within the scope of the claims described below.

Claims (11)

In the first optical transceiver,
Transmitter optical sub-assembly (TOSA);
receiver optical sub-assembly (ROSA);
Wavelength tuning module; and
A controller operatively coupled to the optical transmitting device module, the optical receiving device module, and the wavelength adjustment module, wherein the controller includes:
Receiving information indicating the intensity of a plurality of optical signals corresponding to different wavelengths through the optical receiving element module,
Identifying the amount of change in intensity of the optical signal based on the received information,
Identifying a wavelength that satisfies specified conditions based on the intensity change of the identified optical signal, and
configured to adjust the wavelength of the optical signal transmitted from the optical transmission element module based on the identified wavelength,
The controller, as at least part of an operation of receiving information indicating the intensity of the plurality of optical signals,
Using a filter, obtain a first subcarrier signal that is distinguished from a carrier signal containing communication data from the first optical signal of the first wavelength received through the optical receiving element module,
Demodulating the first subcarrier signal to obtain information indicating the strength of the first optical signal,
Using the filter, obtain a second subcarrier signal that is distinguished from a carrier signal containing communication data from a second optical signal of a second wavelength received through the optical receiving element module,
Demodulating the second subcarrier signal to obtain information indicating the strength of the second optical signal,
Using the filter, a third subcarrier signal that is distinguished from a carrier signal containing communication data is obtained from a third optical signal of a third wavelength received through the optical receiving element module, and
A first optical transceiver configured to obtain information indicating the strength of the third optical signal by demodulating the third subcarrier signal.
delete According to paragraph 1,
The controller, as at least part of the operation of identifying a wavelength that satisfies the specified condition,
Identifying the intensity change amount of the first optical signal and the second optical signal and the intensity change amount of the second optical signal and the third optical signal, and
In response to the identification, a first optical transceiver configured to identify a wavelength that satisfies the specified condition.
According to paragraph 3,
The controller, as at least part of the operation of identifying a wavelength that satisfies the specified condition,
If the intensity change amount of the first optical signal and the second optical signal is greater than the reference change amount, and the intensity change amount of the second optical signal and the third optical signal is less than the reference change amount, the second wavelength is adjusted to the specified condition. A first optical transceiver configured to determine a satisfactory wavelength.
According to paragraph 4,
The controller, as at least part of the operation of adjusting the wavelength of the optical signal transmitted from the optical transmission element module,
By applying a preset value to the second wavelength, a long fourth wavelength is calculated, and
A first optical transceiver configured to adjust the wavelength of the optical signal transmitted from the optical transmission element module to the calculated fourth wavelength.
According to paragraph 1,
The optical transmission device module includes a tunable laser diode whose wavelength of the optical signal is adjusted based on temperature, and
The wavelength adjustment module is a first optical transceiver including a thermo-electric cooler (TEC) for adjusting the temperature of the optical transmission element module.
In the first optical transceiver,
Transmitter optical sub-assembly (TOSA);
receiver optical sub-assembly (ROSA);
Wavelength tuning module; and
A controller operatively coupled to the optical transmitting device module, the optical receiving device module, and the wavelength adjustment module, the controller comprising:
Receive information indicating the intensity of a plurality of optical signals corresponding to different wavelengths through the optical receiving element module,
Generate reference data based on information indicating the intensity of the plurality of optical signals, and
Configured to adjust the wavelength of the optical signal transmitted through the optical transmission element module based on the reference data,
The controller, as at least part of an operation of receiving information indicating the intensity of the plurality of optical signals,
Using a filter, a first subcarrier signal that is distinguished from a carrier signal containing communication data is obtained from the first optical signal of the first wavelength received through the optical receiving element module,
Demodulating the first subcarrier signal to obtain information indicating the strength of the first optical signal,
Using the filter, obtain a second subcarrier signal that is distinguished from a carrier signal containing communication data from a second optical signal of a second wavelength received through the optical receiving element module,
Demodulating the second subcarrier signal to obtain information indicating the strength of the second optical signal,
Using the filter, a third subcarrier signal that is distinguished from a carrier signal containing communication data is obtained from a third optical signal of a third wavelength received through the optical receiving element module, and
A first optical transceiver configured to obtain information indicating the strength of the third optical signal by demodulating the third subcarrier signal.
delete In clause 7,
Contains more memory;
The controller, as at least part of the operation of generating the reference data,
A first optical transceiver configured to generate the reference data by correcting intensity information of optical signals according to wavelengths previously stored in the memory, based on information indicating the intensity of the plurality of optical signals.
In clause 7,
The controller, as at least part of the operation of generating the reference data,
A first optical transceiver configured to generate the reference data by generating intensity information of optical signals according to wavelength from information indicating the intensity of the plurality of optical signals using interpolation.
In clause 7,
The controller, as at least part of the operation of adjusting the wavelength of the optical signal,
Based on the reference data, identify the wavelength range where the intensity of the optical signal is maximum, and
A first optical transceiver configured to adjust the wavelength of the optical signal output from the optical transmission device module through the wavelength adjustment module so that the wavelength of the optical signal transmitted through the optical transmission device module is included in the wavelength range.

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