Wavelength tuning method, apparatus and optical module

Abstract

This application discloses a wavelength tuning method, apparatus, and optical module, relating to the field of optical communication technology. It addresses the current challenge of achieving low-cost, low-power optical network construction using tunable optical modules. The method includes: acquiring the operating wavelength of the optical module; determining an adjustment current value based on a trained wavelength adjustment model when the operating wavelength differs from the target wavelength; and adjusting the drive current of the optical module according to the adjustment current value. Specifically, the grating layer of the optical fiber (DFB) in the optical module is wrapped with a specific two-dimensional material, causing a phase transition in the DFB grating when an external current is applied, changing its refractive index, and thus tuning the DFB output wavelength. The two-dimensional material can be graphene, molybdenum disulfide, black phosphorus, or boron nitride, among others. This application is used for wavelength tuning of optical modules.

Description

Technical Field

[0001] This application relates to the field of optical communication, and in particular to a wavelength tuning method, apparatus and optical module. Background Technology

[0002] Optical communication, as the mainstream data communication method, boasts advantages such as large communication capacity, long relay distance, high security, and strong adaptability. Optical modules, as tools for converting photoelectric signals to and from each other, are one of the key components in optical communication equipment. Among them, wavelength-tunable optical modules have been a subject of extensive research. Wavelength-tunable optical modules can not only fully utilize the broadband resources of optical fibers in dense wavelength division multiplexing (DWDM) systems, thereby greatly improving the communication capacity of network systems, but also offer greater flexibility in networking and component preparation compared to fixed-wavelength DWDM modules. Furthermore, they can serve as backup light sources for traditional DWDM systems, making them a crucial factor in intelligent optical networks.

[0003] The common approach to achieving wavelength tunability is based on distributed feedback laser (DFB) arrays. However, this approach requires multiple DFBs to form an array to create a tunable optical module, resulting in high operating costs. Therefore, how to achieve low-cost, low-power optical network construction for tunable optical modules is a pressing issue that needs to be addressed. Summary of the Invention

[0004] This application provides a wavelength tuning method, apparatus, and optical module, which can solve the current problem of how to build optical networks with tunable optical modules at low cost and low power consumption.

[0005] For the above purposes, this application adopts the following technical solution:

[0006] In a first aspect, this application provides a wavelength tuning method, which includes: acquiring the operating wavelength of an optical module; determining an adjustment current value based on a trained wavelength adjustment model when the operating wavelength differs from the target wavelength; and adjusting the drive current of the optical module based on the adjustment current value.

[0007] In one possible implementation, the above method further includes: constructing a wavelength adjustment model based on a multilayer neural MLP network algorithm; training the wavelength adjustment model according to historical data; wherein the historical data includes one or more of the following: ambient temperature, operating temperature, operating wavelength, and driving current of the optical module; and determining that the wavelength adjustment model training is complete when the prediction effect coefficients corresponding to the wavelength adjustment model meet the first preset condition.

[0008] In one possible implementation, the method further includes: determining a first wavelength offset; wherein the first wavelength offset is used to characterize the degree of offset of the operating wavelength inside the optical module; determining a second wavelength offset; wherein the second wavelength offset is used to characterize the degree of offset of the operating wavelength between the transmitting end and the receiving end of the optical module; determining the actual wavelength offset of the optical module based on the first wavelength offset and the second wavelength offset; and adjusting the driving current of the optical module based on the trained wavelength adjustment model and the actual wavelength offset.

[0009] In one possible implementation, the above method further includes: acquiring the target wavelength of the optical module.

[0010] In one possible implementation, the method further includes: when the operating wavelength is the same as the target wavelength, instructing the semiconductor cooler TEC to control the operating temperature of the optical module to remain constant.

[0011] Secondly, this application provides a wavelength tuning device, which includes: an acquisition unit and a processing unit; the acquisition unit is used to acquire the operating wavelength of the optical module; the processing unit is used to determine the adjustment current value according to a trained wavelength adjustment model when the operating wavelength is different from the target wavelength; the processing unit is also used to adjust the driving current of the optical module according to the adjustment current value.

[0012] In one possible implementation, the processing unit is further configured to construct a wavelength adjustment model based on a multilayer neural MLP network algorithm; the processing unit is further configured to train the wavelength adjustment model based on historical data; wherein the historical data includes one or more of the following: ambient temperature, operating temperature, operating wavelength, and driving current of the optical module; the processing unit is further configured to determine that the wavelength adjustment model training is complete when the prediction effect coefficients corresponding to the wavelength adjustment model meet a first preset condition.

[0013] In one possible implementation, the processing unit is further configured to determine a first wavelength offset, wherein the first wavelength offset is used to characterize the degree of offset of the operating wavelength inside the optical module; the processing unit is further configured to determine a second wavelength offset, wherein the second wavelength offset is used to characterize the degree of offset of the operating wavelength between the transmitting end and the receiving end of the optical module; the processing unit is further configured to determine the actual wavelength offset of the optical module based on the first wavelength offset and the second wavelength offset; the processing unit is further configured to adjust the driving current of the optical module based on the trained wavelength adjustment model and the actual wavelength offset.

[0014] In one possible implementation, the acquisition unit is also used to acquire the target wavelength of the optical module.

[0015] In one possible implementation, the processing unit is also used to instruct the semiconductor cooler TEC to keep the operating temperature of the optical module constant when the operating wavelength is the same as the target wavelength.

[0016] Thirdly, this application provides a computer-readable storage medium storing one or more programs, the one or more programs including instructions that, when executed by an electronic device of this application, cause the electronic device to perform the wavelength tuning method as described in the first aspect and any possible implementation thereof.

[0017] Fourthly, this application provides an electronic device, including: a processor and a memory; wherein the memory is used to store one or more programs, the one or more programs including computer-executable instructions, and when the electronic device is running, the processor executes the computer-executable instructions stored in the memory to cause the electronic device to perform the wavelength tuning method as described in the first aspect and any possible implementation thereof.

[0018] Fifthly, this application provides a computer program product containing instructions that, when executed on a computer, cause the electronic device of this application to perform the wavelength tuning method as described in the first aspect and any possible implementation thereof.

[0019] Sixthly, this application provides a chip system applied to a wavelength tuning device; the chip system includes one or more interface circuits and one or more processors. The interface circuits and the processors are interconnected via lines; the interface circuits are used to receive signals from a memory of the wavelength tuning device and send the signals to the processors, the signals including computer instructions stored in the memory. When the processor executes the computer instructions, the wavelength tuning device performs a wavelength tuning method as described in the first aspect and any possible design of the application.

[0020] In this application, the names of the aforementioned wavelength tuning devices do not limit the devices or functional units themselves. In actual implementation, these devices or functional units may appear under other names. As long as the functions of each device or functional unit are similar to those in this application, they all fall within the scope of the claims of this application and their equivalents.

[0021] Based on the above technical solution, this application modifies the grating region of the DFB in the optical module by wrapping it with a two-dimensional material, enabling the grating of the DFB52 to change its refractive index when an external current is applied, thereby expanding the wavelength tuning range of the DFB52. Therefore, this application can tune the wavelength of the optical signal output by the optical module based on the trained wavelength tuning model, according to the obtained operating wavelength of the optical module and the target wavelength to be tuned. This eliminates the need for splicing multiple DFB lasers; a larger tuning range can be achieved with a single DFB laser, significantly reducing the packaging and manufacturing costs of the optical module. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of a distributed feedback laser provided in an embodiment of this application;

[0023] Figure 2 A schematic diagram of the connection of a distributed feedback laser provided in an embodiment of this application;

[0024] Figure 3 A schematic diagram illustrating the relationship between the complex refractive index and electrical potential energy of graphene provided in an embodiment of this application;

[0025] Figure 4 A schematic diagram of the circuit architecture of a conventional optical module provided for an embodiment of this application;

[0026] Figure 5 A schematic diagram of the circuit architecture of an optical module provided in an embodiment of this application;

[0027] Figure 6 A schematic flowchart illustrating a wavelength tuning method provided in an embodiment of this application;

[0028] Figure 7 A flowchart illustrating another wavelength tuning method provided in this application embodiment;

[0029] Figure 8 A schematic flowchart illustrating another wavelength tuning method provided in an embodiment of this application;

[0030] Figure 9 This is a schematic diagram of the structure of a wavelength tuning device provided in an embodiment of this application;

[0031] Figure 10 This is a schematic diagram of another wavelength tuning device provided in an embodiment of this application. Detailed Implementation

[0032] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0033] In this article, the character " / " generally indicates that the objects before and after it are in an "or" relationship. For example, A / B can be understood as A or B.

[0034] The terms "first" and "second" in the specification and claims of this application are used to distinguish different objects, not to describe a specific order of objects. For example, "first edge service node" and "second edge service node" are used to distinguish different edge service nodes, not to describe a characteristic order of edge service nodes.

[0035] Furthermore, the terms "comprising" and "having," and any variations thereof, used in the description of this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the steps or units listed, but may optionally include other steps or units not listed, or may optionally include other steps or units inherent to such process, method, product, or apparatus.

[0036] Furthermore, in the embodiments of this application, the words "exemplarily" or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplarily" or "for example" in this application should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of the words "exemplarily" or "for example" is intended to present concepts in a concrete manner.

[0037] The following is a description of the technical terms used in this application:

[0038] 1. Distributed feedback laser (DFB)

[0039] DFB lasers primarily use semiconductor materials as the dielectric, including gallium antimonyide (GaSb), gallium arsenide (GaAs), indium phosphide (InP), and zinc sulfide (ZnS). The most significant characteristics of DFB lasers are their excellent monochromaticity (i.e., spectral purity), with linewidths typically below 1 MHz, and very high side-mode suppression ratios, currently reaching over 40-50 dB.

[0040] For example, a schematic diagram of the DFB structure is shown below. Figure 1As shown, the active layer generates photons and provides optical gain; the grating layer uses the Bragg reflection principle to achieve frequency selection. Only when the wavelength simultaneously meets the gain conditions of the active region and the Bragg grating can it be selected and amplified.

[0041] Specifically, when a DFB is operating, after current is injected, the gain medium in the active region undergoes stimulated emission, resulting in electrons undergoing number inversion. Upon returning to the ground state, these electrons emit photons of the corresponding wavelength, which are then reflected by each grating on the surface of the active layer. The Bragg grating achieves longitudinal mode selection based on the grating's frequency selection principle; only light of a specific wavelength that satisfies the following formula will be strongly reflected:

[0042] λ B =2N eff Λ

[0043] Where, λ B For the Bragg wavelength, N eff Λ is the real part of the effective refractive index of the grating, and Λ is the grating period. Only light of a specific wavelength that satisfies the above equation can be lased. DFBs generally achieve tunable output by controlling the effective refractive index of the active region through controlling the operating temperature or driving current. The output wavelength is determined by both the grating period and the effective refractive index of the material. Therefore, common tuning methods for a single DFB include temperature tuning and current tuning: temperature changes cause changes in the refractive index of the semiconductor material, which in turn leads to changes in the Bragg wavelength, ultimately resulting in changes in the DFB's output wavelength; changes in the injected current cause changes in the carrier concentration inside the DFB, leading to changes in the DFB's gain coefficient and the refractive index of the active region. Changes in these two parameters ultimately cause variations in the DFB's output wavelength. The temperature tuning coefficient is approximately 0.1 nm / ℃, and the tuning range is generally no more than 10 nm; the current tuning coefficient is approximately 0.01 nm / mA, and the tuning range is approximately 5–10 nm.

[0044] Both of these tuning methods have limited tuning ranges and slow wavelength stabilization speeds, making it impossible to achieve wide-range wavelength tuning.

[0045] For example, such as Figure 2 As shown, in order to realize the DFB-based tunable optical module, series, parallel, and series-parallel hybrid methods are used to achieve the tuning function.

[0046] In this embodiment, the optical module employs a DFB array structure, and the optical module includes only one DFB. Furthermore, this application encapsulates the grating region of the DFB with a two-dimensional material, such as graphene, molybdenum disulfide, black phosphorus, or boron nitride, to induce a phase transition in the grating encapsulated by the two-dimensional material when an external current is applied, thereby changing its refractive index and tuning the DFB output wavelength. This structure utilizes the sensitivity of the grating cladding to changes in the refractive index of the external environment, reflecting changes in the refractive index of the two-dimensional material onto the grating, thus achieving a change in refractive index.

[0047] 2. Graphene

[0048] Graphene, a two-dimensional planar material composed of a single layer of carbon atoms in a hexagonal honeycomb structure, possesses excellent optoelectronic properties. High-performance broadband optical polarizers and high-speed optical modulators based on graphene have been realized in the laboratory. The electrical conductivity of graphene can be rapidly modulated by changing its chemical potential energy. The surface plasmon resonances excited by graphene are controllable, allowing for convenient dynamic modulation of the refractive index by altering the chemical potential energy of the graphene material through an applied electric field.

[0049] For example, such as Figure 3 As shown, Figure 3 The relationship between the complex refractive index and electrical potential energy of graphene is given, indicating that the electrical conductivity of graphene can be rapidly modulated by changing its chemical potential energy.

[0050] In this application, graphene is used to wrap the grating region of the DFB and is equipped with two metal plate electrodes so that the grating wrapped in two-dimensional material undergoes a phase transition and changes its refractive index by applying an external current.

[0051] Alternatively, the material used to wrap the grating region in this application can also be molybdenum disulfide, black phosphorus, or boron nitride, which have the same properties as graphene.

[0052] The above describes the technical terms involved in this application. The background technology of this application will be explained below.

[0053] Currently, optical communication, as the mainstream data communication method, boasts advantages such as large communication capacity, long relay distance, high security, and strong adaptability. Optical modules, as tools for converting between photoelectric signals and signals, are one of the key components in optical communication equipment. Among them, wavelength-tunable optical modules have been a subject of extensive research. Wavelength-tunable optical modules can not only fully utilize the broadband resources of optical fibers in dense wavelength division multiplexing (DWDM) systems, thereby greatly improving the communication capacity of network systems, but also offer greater flexibility in networking and component preparation compared to fixed-wavelength DWDM modules. Furthermore, they can serve as backup light sources for traditional DWDM systems, making them a crucial factor in intelligent optical networks.

[0054] Currently, there are three main schemes to achieve wavelength tunability: array structure schemes based on external cavity diode lasers (ECDL), distributed Bragg reflectors (DBR), and distributed feedback lasers (DFB), respectively.

[0055] For ECDL, this laser is a hybrid integrated approach that selects the corresponding wavelength through the mechanical movement of external optical components. It can continuously tune the wavelength over a wide wavelength range, has high output power, and can achieve a narrow linewidth. The disadvantages are that the manufacturing of optical components and mechanical systems has high requirements, and the hybrid integrated packaging method is complex and costly, which has prevented large-scale commercial use.

[0056] For DBR, this laser utilizes the vernier effect between two sampled Bragg reflection gratings to achieve wide-range wavelength tuning. Compared to external cavity structures, DBR lasers do not require external mechanical structures, packaging, or adjustment. However, this approach has high requirements for semiconductor processes, requiring active and passive integration, which increases process complexity, reduces yield, and makes the price very high.

[0057] For DFB (Digital Fluorescent Blade), this tunable scheme based on a DFB array can be obtained by combining an array of single-mode lasing DFB semiconductor lasers with a certain wavelength spacing. Since the refractive index of the active material does not change significantly with temperature or current, the tuning range is very small; typically, each DFB semiconductor laser has a tuning range of only 3-4 nm. Currently, DFB-based tunable lasers are generally implemented using an array, employing multiple fixed-wavelength lasers with different wavelengths, coupled together, and selecting one wavelength to operate at a time.

[0058] This application primarily focuses on improving optical modules using distributed feedback laser (DFB) arrays. Current solutions for wavelength-tunable optical modules employing DFB arrays require multiple DFBs to form a tunable module, resulting in high operating costs. Therefore, how to achieve low-cost, low-power optical network construction for tunable optical modules is a pressing issue that needs to be addressed.

[0059] For example, such as Figure 4 The diagram shown is a schematic of the circuit architecture of an optical module in the prior art, including: a microcontroller unit (MCU) 41, a tunable laser 42, a thermoelectric cooler (TEC) 43, a PID analog circuit 44, a TEC driver module 45, a receiveroptical subassembly (ROSA) 46, an Rx clock recovery circuit (RxCDR) 47, a Tx clock recovery circuit (TxCDR) 48, and a host device (HOST) 49.

[0060] Among them, there are two semiconductor coolers 43: one semiconductor cooler 43 is used to maintain the normal operating temperature of the optical module, and the other semiconductor cooler 43 is used to adjust the output wavelength in conjunction with the laser current, and to finely adjust the output wavelength based on the current-adjusted wavelength.

[0061] However, the use of two TEC modules in existing optical modules significantly increases cost and power consumption. This is because, to coordinate and control the two TECs, some manufacturers use pure hardware TEC chips, which are costly; other manufacturers, such as... Figure 4 As shown, a proportional-integral-differential (PID) analog circuit is used to determine temperature regulation, thereby controlling temperature stability and wavelength accuracy. The principle of the PID circuit is to correct the wavelength by correcting the differences between the module temperature value, input current value, and set value and sampled value at different times in the system. However, adding an additional PID analog circuit will increase circuit complexity, packaging cost, and space requirements.

[0062] For example, such as Figure 5The diagram shown is a circuit architecture diagram of an optical module provided in this application, including: a microcontroller unit (MCU) 51, a DFB 52, a Thermo Electric Cooler (TEC) 53, a TEC driver module 54, a receiver optical subassembly (ROSA) 55, an Rx clock recovery circuit (Rx CDR) 56, a Tx clock recovery circuit (Tx CDR) 57, and a host device (HOST) 58.

[0063] Among them, MCU51 is connected to DFB52 and TEC driver module 54 so that MCU51 can control DFB52 and TEC driver module 54.

[0064] In one possible implementation, the MCU51 may store a trained wavelength adjustment model, so that the MCU51 can determine the adjustment current based on the operating wavelength and target wavelength of the optical module, thereby achieving wavelength tuning of the optical signal output by the optical module.

[0065] The DFB52 can output optical signals of different wavelengths according to different drive currents. It should be noted that, because the grating region of the DFB52 in this application is wrapped with a two-dimensional material, a phase transition occurs in the grating when an external current is applied, changing its refractive index and thus tuning the DFB output wavelength. This expands the wavelength tuning range of the DFB52, eliminating the need for multiple DFB lasers; a larger tuning range can be achieved with a single DFB laser, significantly reducing the packaging and manufacturing costs of the optical module.

[0066] The TEC53 is used to regulate the operating temperature of the DFB52. It should be noted that the optical module in this application only has one TEC temperature control module. This is because the MCU in this application stores a wavelength adjustment model. This model can determine the adjustment current value to characterize the current adjustment amplitude after the TEC53 stabilizes the operating temperature of the optical module, based on wavelength requirements, thus precisely adjusting the current to lock the wavelength. This eliminates the need for an additional TEC temperature control module and related PID analog circuitry as in existing technologies, significantly simplifying the optical module's packaging, reducing its size, power consumption, and cost.

[0067] It should be noted that, due to the above improvements, the optical module provided in this application only has one DFB52 and one TEC53.

[0068] TEC drive module 54 is connected to TEC 53 so that TEC drive module 54 can drive and control TEC 63.

[0069] It is understood that the functions of the optical receiving sub-component 55, the receiving clock recovery circuit 56, the transmitting clock recovery circuit 57, and the main device 58 are the same as those of these components in the prior art. This application does not involve any improvement to these components, and the functions of these components will not be described in detail here.

[0070] The flow of the wavelength tuning method provided in this embodiment is described below.

[0071] It should be noted that the wavelength tuning device in this application can be a stand-alone optical communication device, such as the one described above. Figure 5 The optical module shown can also be a functional module or structure in an optical communication device that can realize wavelength tuning, such as the one described above. Figure 5 The MCU51 in the middle.

[0072] For example, such as Figure 6 As shown, this application provides a wavelength tuning method, including the following steps:

[0073] S601, Wavelength tuning device obtains the operating wavelength of the optical module.

[0074] The operating wavelength of the optical module is the wavelength of the optical signal output by the optical module at the current operating moment.

[0075] For example, the wavelength tuning device may include a periodic access controller within the optical module to periodically acquire the operating wavelength of the optical module. The period of this periodic access controller may be set from 30 milliseconds (ms) to 60 milliseconds (ms), and this embodiment does not impose a specific limitation.

[0076] S602. When the operating wavelength is different from the target wavelength, the wavelength tuning device determines the adjustment current value according to the wavelength adjustment model that has been trained.

[0077] The target wavelength is the wavelength of the optical signal output by the optical module currently required. The wavelength tuning device can specifically obtain the target wavelength through the main device connected to the optical module.

[0078] In one possible implementation, the wavelength tuning device can determine the adjustment current value based on the operating wavelength of the optical module and the target wavelength by pre-training a wavelength adjustment model. It should be noted that the specific process for training the wavelength adjustment model is described in S701-S703 below, and will not be repeated here.

[0079] It is understandable that after the wavelength tuning device adjusts the drive current of the optical module according to the adjustment current value, the wavelength of the optical signal output by the optical module is the target wavelength.

[0080] It should be noted that when the operating wavelength is the same as the target wavelength, it means that there is no need to adjust the operating wavelength of the optical module. Therefore, the wavelength tuning device indicates that the TEC controls the operating temperature of the optical module to remain unchanged.

[0081] S603, the wavelength adjustment device adjusts the drive current of the optical module according to the adjustment current value.

[0082] In one possible implementation, when the wavelength tuning device is the aforementioned MCU51, the MCU51 can directly adjust the drive current of the DFB52 according to the adjustment current value, so as to adjust the output wavelength of the DFB52 to the target wavelength, thereby making the wavelength of the optical signal output by the optical module the target wavelength.

[0083] It should be noted that, because the grating region of the DFB52 in this application is covered with a two-dimensional material, a phase transition occurs in the grating when an external current is applied, changing its refractive index and thus tuning the DFB output wavelength. This expands the wavelength tuning range of the DFB52, eliminating the need for multiple DFB lasers; a larger tuning range can be achieved with a single DFB laser, significantly reducing the packaging and manufacturing costs of the optical module.

[0084] Alternatively, the two-dimensional material mentioned above can be graphene, molybdenum disulfide, black phosphorus, and boron nitride, etc.

[0085] The following analysis uses graphene as an example of a two-dimensional material to explain the principle of using a two-dimensional material to wrap a grating layer, causing a phase transition in the grating when an external current is applied, changing its refractive index, and thus tuning the DFB output wavelength:

[0086] When monolayer graphene supports surface plasmon waves, the relationship between its transmission constant and conductivity is shown in the following equation:

[0087]

[0088] Where, σ g Let n be the conductivity of graphene, η0 be the characteristic impedance in vacuum, and then use the relationship n eff = (β / k0), and combining the above relationship, the effective refractive index for propagating surface plasmon waves on graphene can be calculated:

[0089]

[0090] Wherein, the propagation speed of electromagnetic waves in the medium is Where c is the velocity of the electromagnetic wave in a vacuum, ε r μ is the relative permittivity of the medium. rLet be the magnetic permeability of the medium. The refractive index of the medium is calculated. Utilizing the dielectric permeability μ of graphene materials r =1, the expression for the complex refractive index of graphene can be simplified to: ε is the dielectric constant of graphene, and ε0 is the dielectric constant in vacuum. Since the refractive index of graphene is complex, by squaring both sides of the above formula and shifting the terms, the relationship between the real and imaginary parts of the graphene refractive index and the dielectric constant can be expressed as: and ε i =2n r n i .

[0091] It should be noted that, due to graphene's zero band gap structure, electrons in its valence band readily absorb photons and undergo transitions, a process that alters the electron distribution within the graphene band structure. When the voltage is changed, the distribution of electrons in the graphene bands changes, leading to a change in chemical potential energy, which in turn affects the surface conductivity of graphene and consequently alters its effective refractive index. The relationship between voltage and potential energy is as follows:

[0092]

[0093] Where, μ c It is chemical potential energy, V g It is the voltage value, v f It is the fermion speed. Each volt of voltage can change the chemical potential energy by 0.04 eV.

[0094] Therefore, after adding graphene to the DFB grating layer, the emitted wavelength of the DFB interacts with the Bragg grating while simultaneously exciting surface plasmon waves on the graphene surface. This surface wave undergoes energy coupling and exchange with the side modes of the grating, resulting in a change in the emitted wavelength. In other words, it alters the effective refractive index of the medium, making the resonant wavelength tunable. Because the grating's cladding layer is periodically modulated, changes in the electron distribution of the graphene surrounding the grating lead to changes in the grating's refractive index, ultimately resulting in a change in the grating's refractive index.

[0095] The above analysis explains the principle of using graphene as the type of two-dimensional material to wrap the grating layer, causing a phase transition and changing its refractive index when an external current is applied, thereby tuning the DFB output wavelength. It is understandable that when using molybdenum disulfide, black phosphorus, and boron nitride as two-dimensional materials, the principle of causing a phase transition and changing the refractive index of the grating when an external current is applied, thereby tuning the DFB output wavelength, is similar to that of graphene. Both are based on the inherent electrophysical properties of molybdenum disulfide, black phosphorus, and boron nitride, and will not be elaborated further in this application.

[0096] Based on the above technical solution, this application embodiment modifies the grating region of the DFB in the optical module by wrapping it with a two-dimensional material, so that the grating of the DFB52 can change its refractive index when an external current is applied, thereby expanding the wavelength adjustment range of the DFB52. Therefore, this application can tune the wavelength of the optical signal output by the optical module based on the trained wavelength adjustment model and according to the obtained operating wavelength of the optical module and the target wavelength to be adjusted, without the need for splicing multiple DFB lasers. A larger tuning range can be achieved with a single DFB laser, which greatly reduces the packaging and process cost of the optical module.

[0097] For example, combined Figure 6 ,like Figure 7 As shown, the wavelength tuning method provided in this application further includes the following steps:

[0098] The S701 wavelength tuning device is based on a multilayer neural MLP network algorithm to construct a wavelength adjustment model.

[0099] Among them, the MLP network algorithm is a mature technology in this field. Specifically, the method of constructing a wavelength adjustment model based on the multilayer neural MLP network algorithm can be found in the prior art, and will not be described in detail here.

[0100] S702. The wavelength tuning device trains a wavelength adjustment model based on the historical data.

[0101] Optionally, historical data may include one or more of the following: ambient temperature, operating temperature, operating wavelength, and drive current of the optical module.

[0102] In one possible implementation, the wavelength tuning device trains the wavelength adjustment model built in the S701 based on historical data of the optical module's ambient temperature, operating temperature, wavelength, and operating current. The training process is described in detail below:

[0103] 1) Use This represents the input value (i.e., activation value) of the first layer of neurons. The activation values ​​for each subsequent layer are achieved using the following steps:

[0104]

[0105]

[0106]

[0107] Where, x i This is a set of historical data (ambient temperature, operating temperature, wavelength); This is the output value of the i-th node in the l-th layer; Let be the activation value of the i-th node in the (l+1)-th layer. The connection weight parameter between the i-th node in the l-th layer and the j-th node in the (l+1)-th layer; is the intercept term of the j-th node in the (l+1)-th layer; f is the activation function, with the hidden layer and output layer using the tansig and logsig activation functions respectively; the output layer is the corresponding current value.

[0108] 2) Take the sum of squared errors of all output layer nodes of the network as the loss function, as follows:

[0109]

[0110] Among them, y i Configure expected values ​​for the expert parameters of the output layer i-node, a i Output the value for node i in the output layer.

[0111] 3) By iterating over the weights W and biases b to minimize the loss function, the network output value gets closer and closer to the true value:

[0112]

[0113]

[0114] Where α is the learning rate, and its value ranges from 0 to 1.

[0115] 4) The predictive performance of the MLP model is evaluated using the equal coefficient EC.

[0116]

[0117] In the formula, y k For the actual value, a k The value is the predicted value, and its range is (0,1). For example, if the EC value is greater than 0.9, it indicates that the fitting result is ideal, and at this time the wavelength tuning device determines that the wavelength adjustment model training is complete.

[0118] It should be noted that the above-described training method for the wavelength adjustment model is only one possible implementation provided by the embodiments of this application, and does not constitute a limitation on the training method for the wavelength adjustment model.

[0119] S703. When the prediction effect coefficients corresponding to the wavelength adjustment model meet the first preset condition, the wavelength adjustment device determines that the wavelength adjustment model training is complete.

[0120] For example, as described in S702 above, the prediction effect coefficient can be the equal coefficient EC in S702, and the first preset condition can be that the equal coefficient EC is greater than 0.9. When the equal coefficient EC corresponding to the wavelength adjustment model is greater than 0.9, the wavelength tuning device determines that the wavelength adjustment model training is complete. Optionally, the wavelength tuning device stores the trained wavelength adjustment model in the microcontroller unit (MCU) of the optical module.

[0121] Based on the above technical solution, this application embodiment constructs and trains a wavelength adjustment model. After stabilizing the operating temperature of the optical module using TEC according to the target wavelength, the current adjustment amplitude is determined according to the wavelength adjustment model, and the current is precisely adjusted to lock the wavelength of the output optical signal of the optical module. Therefore, this application embodiment can more accurately and intelligently lock the required wavelength in any environment in one step, without needing to adjust the wavelength twice using current and temperature. Furthermore, the final wavelength adjustment amplitude of the wavelength adjustment model is only related to the current state of the optical module, eliminating the need to accumulate historical deviations to confirm the adjustment value as in the prior art PID circuit. Therefore, the solution of this application embodiment can improve system stability.

[0122] For example, combined Figure 6 ,like Figure 8 As shown, the wavelength tuning method provided in this application further includes the following steps:

[0123] It should be noted that during the actual tuning process of the optical module, the laser in the optical module experiences a decrease in reliability over time, which can cause the wavelength of the optical module to shift under the same current. If the wavelength shift of the optical module is too severe, the corresponding channel of the optical module will be unable to transmit optical signals, and the corresponding optical module will also be unable to receive the transmitted optical signals normally, resulting in service interruption for that channel. To avoid this situation, this application monitors and controls the wavelength shift of the optical module through the following steps S801-S804.

[0124] S801, Wavelength tuning device determines the first wavelength offset.

[0125] The first wavelength offset is used to characterize the degree of offset of the working wavelength inside the optical module.

[0126] Optionally, the wavelength tuning device can periodically acquire the first wavelength offset of the optical module by setting a periodic access controller within the optical module. Specifically, the first wavelength offset is the interpolation between the current actual wavelength and the target wavelength. Optionally, different query cycles can be set for optical modules under different environments, health conditions, and operating states, which can reduce power consumption to a certain extent. For example, the cycle of the periodic access controller can be set from 30 milliseconds (ms) to 60 milliseconds; this embodiment does not impose specific limitations.

[0127] It is understandable that the wavelength tuning device determines the first wavelength offset, which is equivalent to establishing an internal feedback mechanism for the optical module, and thus determining the wavelength offset based on this internal feedback mechanism.

[0128] S802, Wavelength tuning device determines the second wavelength offset.

[0129] The second wavelength offset is used to characterize the degree of wavelength offset between the transmitting and receiving ends of the optical module.

[0130] Optionally, the wavelength tuning device can periodically acquire the second wavelength offset of the optical module by setting a periodic access controller between the transmitting and receiving ends of the optical module; or, the transmitting and receiving ends of the optical module can determine the wavelength offset through periodic wavelength test messages, and the wavelength tuning device can acquire the wavelength offset to periodically acquire the second wavelength offset of the optical module.

[0131] It is understandable that the wavelength tuning device determines the first wavelength offset, which is equivalent to establishing an external feedback mechanism for the optical module to determine the wavelength offset through wavelength test messages from the transceiver end.

[0132] Optionally, the wavelength tuning device can be configured to adjust the number of queries for the external feedback mechanism to meet the requirements of the internal feedback mechanism, ensuring that the optical module operates normally.

[0133] S803, the wavelength tuning device determines the actual wavelength offset of the optical module based on the first wavelength offset and the second wavelength offset.

[0134] Optionally, when the wavelength tuning device can be configured to adjust the number of queries for the external feedback mechanism in accordance with the requirements of the internal feedback mechanism, the wavelength tuning device will determine the second wavelength offset as the actual wavelength offset of the optical module.

[0135] In one possible implementation, when one and only one of the first wavelength offset and the second wavelength offset is 0, the wavelength tuning device determines the other non-zero wavelength offset as the actual wavelength offset of the optical module.

[0136] In one possible implementation, when the first wavelength offset and the second wavelength offset are both non-zero and the same, the wavelength tuning device determines any one of the wavelength offsets as the actual wavelength offset of the optical module.

[0137] S804: The wavelength tuning device adjusts the drive current of the optical module based on the trained wavelength adjustment model and the actual wavelength offset.

[0138] Optionally, the wavelength tuning device determines the current value that needs to be adjusted at this time based on the trained wavelength adjustment model and the actual wavelength offset, and adjusts the drive current of the optical module according to the current value.

[0139] Based on the above technical solutions, this application embodiment avoids the untimely reporting of wavelength offset caused by a single wavelength feedback locking mechanism and the resource waste caused by relying solely on wavelength test messages to determine wavelength offset by setting an internal and external dual feedback mechanism. The internal feedback mechanism of this application sets a periodic wavelength query within the optical module to determine the wavelength offset. Different query cycles can be set for optical modules in different environments, with different health levels, and under different operating states, which can reduce power consumption to a certain extent. The external feedback mechanism determines the wavelength offset through wavelength test messages from the transceiver end. In conjunction with the needs of the internal feedback, the number of external feedback queries is set to ensure the normal operation of the optical module. Therefore, even without a TEC in the optical module, the internal and external dual feedback mechanisms added in this application embodiment can ensure the accuracy of the wavelength of the output optical signal of the optical module.

[0140] This application embodiment can divide the wavelength tuning device into functional modules or functional units according to the above method examples. For example, each function can be divided into a separate functional module or functional unit, or two or more functions can be integrated into one processing module. The integrated module can be implemented in hardware or in software functional modules or functional units. The module or unit division in this application embodiment is illustrative and only represents one logical functional division; other division methods may be used in actual implementation.

[0141] For example, such as Figure 9 The diagram shown is a possible structural schematic of a wavelength tuning device according to an embodiment of this application. The wavelength tuning device 900 includes an acquisition unit 901 and a processing unit 902.

[0142] The acquisition unit 901 is used to acquire the operating wavelength of the optical module.

[0143] The processing unit 902 is used to determine the adjustment current value based on the trained wavelength adjustment model when the working wavelength is different from the target wavelength.

[0144] The processing unit 902 is also configured to adjust the driving current of the optical module according to the adjustment current value.

[0145] Optionally, the processing unit 902 is also used to construct the wavelength adjustment model based on a multilayer neural MLP network algorithm.

[0146] Optionally, the processing unit 902 is further configured to train the wavelength adjustment model based on the historical data. The historical data includes one or more of the following: the ambient temperature, operating temperature, operating wavelength, and drive current of the optical module.

[0147] Optionally, the processing unit 902 is further configured to determine that the wavelength adjustment model training is complete when the prediction effect coefficients corresponding to the wavelength adjustment model meet the first preset condition.

[0148] Optionally, the processing unit 902 is further configured to determine a first wavelength offset. The first wavelength offset characterizes the degree of offset of the operating wavelength within the optical module.

[0149] Optionally, the processing unit 902 is further configured to determine a second wavelength offset. The second wavelength offset characterizes the degree of wavelength shift between the transmitting and receiving ends of the optical module.

[0150] Optionally, the processing unit 902 is further configured to determine the actual wavelength offset of the optical module based on the first wavelength offset and the second wavelength offset.

[0151] Optionally, the processing unit 902 is further configured to adjust the driving current of the optical module according to the trained wavelength adjustment model and the actual wavelength offset.

[0152] Optionally, the acquisition unit 901 is also used to acquire the target wavelength of the optical module.

[0153] Optionally, the processing unit 902 is further configured to instruct the semiconductor cooler TEC to maintain a constant operating temperature of the optical module when the operating wavelength is the same as the target wavelength.

[0154] Optionally, the wavelength tuning device 900 may also include a storage unit ( Figure 9 (shown in dashed box) The storage unit stores a program or instruction. When the acquisition unit 901 and the processing unit 902 execute the program or instruction, the wavelength tuning device can perform the wavelength tuning method described in the above method embodiment.

[0155] also, Figure 9 The technical effects of the wavelength tuning device can be referred to the technical effects of the wavelength tuning method described in the above embodiments, and will not be repeated here.

[0156] For example, Figure 10 This is a schematic diagram of another possible structure of the wavelength tuning device involved in the above embodiments. For example... Figure 10 As shown, the wavelength tuning device 1000 includes: a processor 1002.

[0157] The processor 1002 is used to control and manage the operation of the wavelength tuning device, for example, to execute the steps performed by the acquisition unit 901 and the processing unit 902, and / or to execute other processes of the technical solution described herein.

[0158] The processor 1002 described above can implement or execute various exemplary logic blocks, modules, and circuits described in conjunction with the contents of this application. The processor can be a central processing unit, a general-purpose processor, a digital signal processor, an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. It can implement or execute various exemplary logic blocks, modules, and circuits described in conjunction with the contents of this application. The processor can also be a combination that implements computational functions, such as a combination of one or more microprocessors, a combination of a DSP and a microprocessor, etc.

[0159] Optionally, the wavelength tuning device 1000 may further include a communication interface 1003, a memory 1001, and a bus 1004. The communication interface 1003 supports communication between the wavelength tuning device 1000 and other network entities. The memory 1001 stores the program code and data of the wavelength tuning device.

[0160] The memory 1001 may be a memory in a wavelength tuning device, and the memory may include volatile memory, such as random access memory; the memory may also include non-volatile memory, such as read-only memory, flash memory, hard disk or solid-state drive; the memory may also include a combination of the above types of memory.

[0161] Bus 1004 can be an Extended Industry Standard Architecture (EISA) bus, etc. Bus 1004 can be divided into address bus, data bus, control bus, etc. For ease of representation, Figure 10 The bus is represented by a single thick line, but this does not mean that there is only one bus or one type of bus.

[0162] Through the above description of the embodiments, those skilled in the art will clearly understand that, for the sake of convenience and brevity, only the division of the above functional modules is used as an example. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. The specific working process of the system, device and module described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0163] This application provides a computer program product containing instructions that, when run on the electronic device of this application, causes the computer to execute the wavelength tuning method described in the above method embodiments.

[0164] This application also provides a computer-readable storage medium storing instructions. When a computer executes these instructions, the electronic device of this application performs each step of the wavelength tuning device in the method flow shown in the above method embodiment.

[0165] The computer-readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of computer-readable storage media (a non-exhaustive list) include: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), registers, hard disks, optical fibers, compact disc read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing, or any other form of computer-readable storage medium in the art. An exemplary storage medium is coupled to a processor, enabling the processor to read information from and write information to the storage medium. Of course, the storage medium may also be a component of the processor. The processor and the storage medium may reside in an application-specific integrated circuit (ASIC). In the embodiments of this application, the computer-readable storage medium can be any tangible medium that contains or stores a program that can be used by or in conjunction with an instruction execution system, apparatus, or device.

[0166] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A wavelength tuning method, characterized in that, The optical module is used in an optical module, which includes: a DFB, a semiconductor cooler (TEC), a TEC driver module, and a microcontroller unit (MCU). The DFB includes a grating layer, which is wrapped with a two-dimensional material, so that the grating of the DFB can change its refractive index when an external current is applied; the two-dimensional material includes one or more of the following: graphene, molybdenum disulfide, black phosphorus and boron nitride; The TEC is used to regulate the operating temperature of the DFB; the TEC drive module is connected to the TEC so that the TEC drive module can drive and control the TEC. The MCU is connected to the DFB so that the MCU can control the DFB; the MCU stores a wavelength adjustment model, which is used to control the operating wavelength of the DFB. The method includes: Obtain the operating wavelength of the optical module; A first wavelength offset is determined, which is used to characterize the degree of offset of the operating wavelength inside the optical module; Based on the periodic wavelength test messages between the transmitter and receiver of the optical module, a second wavelength offset is determined. The second wavelength offset is used to characterize the degree of offset of the operating wavelength between the transmitter and receiver of the optical module. The actual wavelength offset of the optical module is determined based on the first wavelength offset and the second wavelength offset; When the operating wavelength is different from the target wavelength, the adjustment current value is determined based on the trained wavelength adjustment model and the actual wavelength offset. The driving current of the optical module is adjusted according to the adjusted current value.

2. The method according to claim 1, characterized in that, The method further includes: The wavelength adjustment model is constructed based on a multilayer neural MLP network algorithm; The wavelength adjustment model is trained based on historical data; wherein the historical data includes one or more of the following: ambient temperature, operating temperature, operating wavelength, and drive current of the optical module; If the prediction performance coefficients corresponding to the wavelength adjustment model meet the first preset condition, the wavelength adjustment model is determined to have completed training.

3. The method according to claim 1 or 2, characterized in that, The method further includes: Obtain the target wavelength of the optical module.

4. The method according to claim 1, characterized in that, The method further includes: When the operating wavelength is the same as the target wavelength, the thermoelectric cooler (TEC) controls the operating temperature of the optical module to remain constant.

5. A wavelength tuning device, characterized in that, The wavelength tuning device includes: an acquisition unit and a processing unit; The acquisition unit is used to acquire the operating wavelength of the optical module; The processing unit is used to determine a first wavelength offset, which is used to characterize the degree of offset of the working wavelength inside the optical module. The processing unit is further configured to determine a second wavelength offset based on periodic wavelength test messages between the transmitting end and the receiving end of the optical module. The second wavelength offset is used to characterize the degree of offset of the operating wavelength between the transmitting end and the receiving end of the optical module. The processing unit is further configured to determine the actual wavelength offset of the optical module based on the first wavelength offset and the second wavelength offset; The processing unit is also used to determine the adjustment current value based on the trained wavelength adjustment model and the actual wavelength offset when the working wavelength is different from the target wavelength. The processing unit is further configured to adjust the driving current of the optical module according to the adjustment current value; The optical module includes: a DFB, a semiconductor cooler TEC, a TEC driver module, and a microcontroller MCU; The DFB includes a grating layer, which is wrapped with a two-dimensional material, so that the grating of the DFB can change its refractive index when an external current is applied; the two-dimensional material includes one or more of the following: graphene, molybdenum disulfide, black phosphorus and boron nitride; The TEC is used to regulate the operating temperature of the DFB; the TEC drive module is connected to the TEC so that the TEC drive module can drive and control the TEC. The MCU is connected to the DFB so that the MCU can control the DFB; the MCU stores a wavelength adjustment model, which is used to control the operating wavelength of the DFB.

6. The wavelength tuning device according to claim 5, characterized in that, The processing unit is also used to construct the wavelength adjustment model based on a multilayer neural MLP network algorithm; The processing unit is further configured to train the wavelength adjustment model based on historical data; wherein the historical data includes one or more of the following: ambient temperature, operating temperature, operating wavelength, and driving current of the optical module; The processing unit is further configured to determine that the wavelength adjustment model training is complete when the prediction effect coefficients corresponding to the wavelength adjustment model meet the first preset condition.

7. The wavelength tuning device according to claim 5 or 6, characterized in that, The acquisition unit is also used to acquire the target wavelength of the optical module.

8. The wavelength tuning device according to claim 5, characterized in that, The processing unit is also used to instruct the semiconductor cooler TEC to keep the operating temperature of the optical module constant when the operating wavelength is the same as the target wavelength.

9. An electronic device, characterized in that, include: A processor and a memory; wherein the memory is used to store computer execution instructions, and when the electronic device is running, the processor executes the computer execution instructions stored in the memory to cause the electronic device to perform the wavelength tuning method as described in any one of claims 1-4.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium includes instructions that, when executed by an electronic device, enable the electronic device to perform the wavelength tuning method as described in any one of claims 1-4.

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