A kind of micro-ring wavelength division multiplexing system and its optical channel monitoring method, device

Abstract

The application discloses a kind of micro-ring wavelength division multiplexing systems and its optical channel monitoring method, device, applied to optical fiber communication technical field, to solve the problem of accurately identifying the shift of micro-ring operating wavelength, multiple optical label generation module generates the optical signal label corresponding to each laser one by one;Laser adopts received optical signal label to modulate the light source signal generated by itself to obtain modulated light source signal;Optical coupler carries out wavelength division multiplexing to each modulated light source signal and is transmitted to micro-ring modulation array by waveguide;Micro-ring modulator array is transmitted to the optical signal that is matched with itself tuning wavelength by each micro-ring modulator;Optical signal detection module determines the shift of micro-ring modulator operating wavelength according to the current optical signal label in the optical signal that each micro-ring modulator respectively outputs and the optical signal label of target laser corresponding to micro-ring modulator;It improves the detection accuracy of the shift of micro-ring modulator operating wavelength.

Description

Technical Field

[0001] This invention relates to the field of optical fiber communication technology, and in particular to a micro-ring wavelength division multiplexing system and its optical channel monitoring method and device. Background Technology

[0002] Dense Wavelength Division Multiplexing (DWDM) technology is a technique that simultaneously and independently multiplexes multiple optical signals of different wavelengths onto a single optical fiber for transmission, significantly increasing the transmission capacity of a single fiber. In DWDM technology based on silicon-based microring devices, the high thermo-optical coefficient and steep resonance characteristics of silicon make the resonant wavelength of the microrings susceptible to drift due to changes in ambient temperature. For DWDM systems with operating wavelengths set near the standard grid wavelength, the large temperature drift coefficient of silicon-based microring devices can easily cause the device's operating wavelength to deviate from the preset grid channel, and may even deviate to adjacent channels, resulting in continuous crosstalk between adjacent channels and a degraded system transmission performance. Therefore, during long-term operation of a dense wavelength division multiplexing system, it is necessary to monitor and correct the optical channels.

[0003] Currently, the offset between the operating wavelength of the microring and the wavelength of the light source signal is usually determined by monitoring the optical power of the output ports such as the through port or drop port. However, this method of relying solely on changes in optical power cannot accurately identify the offset of the microring's operating wavelength. Summary of the Invention

[0004] The purpose of this invention is to provide a micro-ring wavelength division multiplexing system and its optical channel monitoring method and device, which can improve the detection accuracy of the offset of the working wavelength of the micro-ring modulator during use.

[0005] To address the aforementioned technical problems, the embodiments of the present invention provide the following technical solutions: This invention provides a micro-ring wavelength division multiplexing system, comprising: Multiple optical tag generation modules are used to generate optical signal tags that correspond one-to-one with each laser; A laser connected to each of the optical tag generation modules is used to modulate the light source signal generated by itself using the received optical signal tag to obtain the modulated light source signal. An optical coupler connected to each of the lasers is used to perform wavelength division multiplexing on each of the modulated light source signals and transmit the wavelength division multiplexed optical signals to the micro-ring modulation array through a waveguide; A microring modulator array is used to transmit optical signals that are matched to their own tuning wavelengths through individual microring modulators; An optical signal detection module is used to acquire the optical signals output by each of the micro-ring modulators, and to determine the offset of the operating wavelength of the micro-ring modulator based on the current optical signal tag in the optical signal and the optical signal tag of the target laser corresponding to the micro-ring modulator.

[0006] In one embodiment, the optical tag generation module is a low-frequency signal generator; Each low-frequency signal generator is used to generate multiple low-frequency periodic perturbation signals with different frequencies and amplitudes; each of the low-frequency periodic perturbation signals is an optical signal tag and corresponds to a laser.

[0007] In one embodiment, the optical signal detection module includes: A photoelectric conversion module, which is connected to each micro-ring modulator in a one-to-one manner, is used to convert the optical signal output by the corresponding micro-ring modulator into an electrical signal. A filter module, connected one-to-one with each of the photoelectric conversion modules, is used to filter the electrical signal using a target frequency to obtain a filtered electrical signal; the target frequency is set based on the frequency of the optical signal tag of the target laser corresponding to the micro-ring modulator; A signal processing module, which is connected to each of the filter modules in a one-to-one manner, is used to determine the offset of the operating wavelength of the micro-ring modulator based on the filtered electrical signal.

[0008] In one embodiment, the signal processing module is specifically used to determine whether the amplitude of the filtered electrical signal is within the corresponding preset amplitude range. If so, the operating wavelength of the micro-ring modulator has not shifted; if not, the operating wavelength of the micro-ring modulator has shifted.

[0009] In one embodiment, it further includes: a control module connected to the signal processing module and a micro heater connected to the control module, corresponding to each of the micro-ring modulators; The control module is used to adjust the power of the micro heater corresponding to the micro ring modulator when the operating wavelength of the corresponding micro ring modulator is deviated based on the output signal of the signal processing module.

[0010] In one embodiment, the photoelectric conversion module includes a first photodetector and a second photodetector, and the filter module includes a first filter and a second filter; wherein, the input terminal of the first photodetector is connected to the input terminal of the micro-ring modulator, the output terminal of the first photodetector is connected to the input terminal of the first filter, the output terminal of the first filter is connected to the first input terminal of the signal processing module, the input terminal of the second photodetector is connected to the output terminal of the micro-ring modulator, the output terminal of the second photodetector is connected to the input terminal of the second filter, and the output terminal of the second filter is connected to the second input terminal of the signal processing module; The first photodetector is used to convert the input optical signal of the micro-ring modulator into a first electrical signal; The second photodetector is used to convert the output optical signal of the micro-ring modulator into a second electrical signal; The first filter is used to filter the first electrical signal to obtain the first optical power signal; The second filter is used to filter the second electrical signal to obtain the second optical power signal and the optical tag signal; The signal processing module is used to determine the offset of the operating wavelength of the micro-ring modulator based on the optical tag signal and generate an offset result signal, and to normalize the second optical power signal according to the first optical power signal to obtain a normalized optical power signal. The control module is used to adjust the power of the micro heater corresponding to the micro ring modulator based on the normalized optical power signal when the operating wavelength of the corresponding micro ring modulator is determined to be offset based on the offset result signal.

[0011] In one embodiment, the signal processing module includes a divider, a first analog-to-digital converter (ADC), a second ADC, and an optical tag detection module. The first input terminal of the divider is connected to the output terminal of the first filter, the second input terminal of the divider is connected to the first sub-output terminal of the second filter, the output terminal of the divider is connected to the input terminal of the first ADC, the output terminal of the first ADC is connected to the first input terminal of the control module, the input terminal of the second ADC is connected to the second sub-output terminal of the second filter, the output terminal of the second ADC is connected to the input terminal of the optical tag detection module, and the output terminal of the optical tag detection module is connected to the second input terminal of the control module. The divider is used to normalize the second optical power signal based on the first optical power signal to obtain a normalized optical power signal. The first analog-to-digital converter is used to convert the normalized optical power signal into a corresponding optical power digital signal. The second analog-to-digital converter is used to convert the optical tag signal into a corresponding optical tag digital signal; The optical tag detection module is used to determine the offset of the operating wavelength of the micro-ring modulator by the digital signal of the optical tag and generate an offset result signal.

[0012] In one embodiment, the system further includes: a first transimpedance amplifier and a second transimpedance amplifier; wherein the input terminal of the first transimpedance amplifier is connected to the output terminal of the first photodetector, the output terminal of the first transimpedance amplifier is connected to the input terminal of the first filter, the input terminal of the second transimpedance amplifier is connected to the output terminal of the second photodetector, and the output terminal of the second transimpedance amplifier is connected to the input terminal of the second filter.

[0013] Another aspect of the present invention provides a method for monitoring the optical channel of a micro-ring wavelength division multiplexing system, comprising: Obtain the optical signal tag that corresponds to each laser; Each of the aforementioned optical signal tags modulates the light source signal generated by the corresponding laser to obtain a modulated light source signal; Each of the modulated light source signals is wavelength divided and multiplexed, and the wavelength divided and multiplexed optical signal is transmitted to the micro-ring modulation array through a waveguide; For each micro-ring modulator in the micro-ring modulation array, the optical signal output by the micro-ring modulator is acquired; The offset of the operating wavelength of the micro-ring modulator is determined based on the current optical signal tag in the optical signal and the optical signal tag of the target laser corresponding to the micro-ring modulator.

[0014] Another aspect of the present invention provides an optical channel monitoring device for a micro-ring wavelength division multiplexing system, comprising: The first acquisition module is used to acquire optical signal tags that correspond one-to-one with each laser. A modulation module is used to modulate the light source signal generated by the corresponding laser using each of the optical signal tags to obtain a modulated light source signal. The multiplexing module is used to perform wavelength division multiplexing on each of the modulated light source signals and transmit the wavelength division multiplexed optical signal to the micro-ring modulation array through a waveguide. The second acquisition module is used to acquire the optical signal output by each micro-ring modulator in the micro-ring modulation array. The analysis module is used to determine the offset of the operating wavelength of the micro-ring modulator based on the current optical signal tag in the optical signal and the optical signal tag of the target optical channel corresponding to the micro-ring modulator.

[0015] As can be seen from the above technical solutions, the embodiments of the present invention have the following advantages: This invention provides a micro-ring wavelength division multiplexing (WDM) system, comprising: multiple optical tag generation modules for generating optical signal tags corresponding one-to-one with each laser; lasers connected one-to-one with each optical tag generation module for modulating their own generated light source signals using the received optical signal tags to obtain modulated light source signals; optical couplers connected to each laser for performing WDM multiplexing on each modulated light source signal and transmitting the WDM multiplexed optical signal to a micro-ring modulation array via a waveguide; a micro-ring modulator array for transmitting optical signals matched to their own tuning wavelengths through each micro-ring modulator; and an optical signal detection module for acquiring the optical signals output by each micro-ring modulator and determining the offset of the operating wavelength of the micro-ring modulator based on the current optical signal tag in the optical signal and the optical signal tag of the target laser corresponding to the micro-ring modulator.

[0016] Therefore, this application sets up a corresponding optical tag generation module for each laser. Each optical tag generation module generates an optical signal tag that uniquely corresponds to the laser. Each laser corresponds to an optical channel. The laser uses the corresponding optical signal tag to modulate the emitted light source signal to obtain a modulated light source signal. The optical coupler performs wavelength division multiplexing on the received modulated light source signals and couples them to the same waveguide for transmission to the micro-ring modulator array. Each micro-ring modulator in the micro-ring modulator array can modulate its own harmonics to match the wavelength of the light signal emitted by the corresponding laser, thereby realizing the transmission of the light signal that matches its own tuned wavelength. After the optical signal detection module obtains the light signal output by each micro-ring modulator, it can accurately determine the offset of the working wavelength of the corresponding micro-ring modulator based on the current optical signal tag in the light signal and the optical signal tag of the target laser corresponding to the micro-ring modulator. In this application, the optical signal tag uniquely corresponding to the laser is integrated with the light source signal emitted by the laser and transmitted to the micro-ring modulator array through an optical coupler and a waveguide. Then, by detecting and analyzing the current optical signal tag in the optical signal output by each micro-ring modulator in the micro-ring modulator array, the offset of the operating wavelength of the corresponding micro-ring modulator can be determined, thereby improving the accuracy of detecting the offset of the operating wavelength of the micro-ring modulator.

[0017] Furthermore, the optical channel monitoring method and device for the micro-ring wavelength division multiplexing system provided by this invention have corresponding advantages. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the prior art and embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the structure of a micro-ring wavelength division multiplexing system provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of another micro-ring wavelength division multiplexing system provided in an embodiment of the present invention; Figure 3 This is a partial structural schematic diagram of a micro-ring wavelength division multiplexing system provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of another micro-ring wavelength division multiplexing system provided in an embodiment of the present invention; Figure 5 A partial structural block diagram of a micro-ring wavelength division multiplexing system provided in an embodiment of the present invention; Figure 6 A partial structural block diagram of another micro-ring wavelength division multiplexing system provided in an embodiment of the present invention; Figure 7 A flowchart of optical signal tag detection in a micro-ring wavelength division multiplexing system provided in this embodiment of the invention; Figure 8 A control flowchart of a microheater for a microring wavelength division multiplexing system provided in an embodiment of the present invention; Figure 9 A flowchart of an optical channel monitoring method for a micro-ring wavelength division multiplexing system provided in an embodiment of the present invention; Figure 10 This is a structural diagram of an optical channel monitoring device for a micro-ring wavelength division multiplexing system provided in an embodiment of the present invention. Detailed Implementation

[0020] This invention provides a micro-ring wavelength division multiplexing system and its optical channel monitoring method and device, which can improve the detection accuracy of the offset of the working wavelength of the micro-ring modulator during use.

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Please refer to Figure 1 , Figure 1 A schematic flowchart of a micro-ring wavelength division multiplexing system provided in an embodiment of the present invention. The micro-ring wavelength division multiplexing system includes: Multiple optical tag generation modules 1 are used to generate optical signal tags that correspond one-to-one with each laser 2; The laser 2, which is connected to each optical tag generation module 1 in a one-to-one manner, is used to modulate the light source signal generated by itself using the received optical signal tag to obtain the modulated light source signal. The optical coupler 3, which is connected to each laser 2, is used to perform wavelength division multiplexing on each modulated light source signal and transmit the wavelength division multiplexed optical signal to the micro-ring modulation array 4 through a waveguide; Micro-ring modulator array 4 is used to transmit optical signals that are matched to their own tuning wavelengths through each micro-ring modulator; The optical signal detection module 5 is used to acquire the optical signals output by each micro-ring modulator and determine the offset of the working wavelength of the micro-ring modulator based on the current optical signal tag in the optical signal and the optical signal tag of the target laser corresponding to the micro-ring modulator.

[0023] It should be noted that in this embodiment, each laser 2 is provided with a corresponding optical tag generation module 1. This module generates a unique optical signal tag for each laser 2, which is then transmitted to the corresponding laser 2. Each laser 2 generates continuous light of a specific wavelength; in this application, the continuous light generated by the laser 2 is referred to as a light source signal. In other words, each laser generates a light source signal of a preset wavelength. In practical applications, the laser 2 driver integrates a dedicated electrical modulator. This modulator receives the optical signal tag sent by the corresponding optical tag generation module 1 and modulates the light source signal emitted by the laser 2 according to the optical signal tag, thereby forming a unique dynamic tag on the optical channel corresponding to that laser 2. That is, by modulating the light source signal generated by the corresponding laser 2 with each optical tag signal, a modulated light source signal corresponding to each laser 2 can be obtained, and each modulated light source signal carries an independent dynamic tag. Each laser 2 sends its modulated light source signal to the optical coupler 3. The optical coupler 3 can couple each light source signal with an independent optical signal tag and a different wavelength into a waveguide, complete wavelength division multiplexing, and send it to the micro-ring modulator array 4.

[0024] Each micro-ring modulator in the micro-ring modulator array 4 has a corresponding resonant wavelength. The wavelength of each micro-ring modulator can be pre-adjusted to a preset wavelength corresponding to each laser 2, thus matching the tuning wavelength of each micro-ring modulator with the preset wavelength of its corresponding laser 2. The tuning wavelength of the micro-ring modulator can be exactly the same as the preset wavelength of its corresponding laser 2, or it can be within a preset range near the preset wavelength of its corresponding laser 2, depending on actual needs. Each micro-ring modulator responds to and transmits an optical signal whose tuning wavelength matches its own. By loading high-speed service electrical signals onto the tuning ports of each micro-ring modulator, independent high-speed modulation of all wavelength channels can be achieved, completing the optical domain loading of service data. Specifically, when the wavelength of a micro-ring modulator is aligned with the wavelength of the input light source channel, the optical tag signal carried by the light source signal can pass through the micro-ring modulator with low loss, while other wavelengths are suppressed. In practical applications, each micro-ring modulator's output can be connected to a coupler. Through this coupler, a small portion of the optical signal (or optical power) from the output waveguide of the micro-ring modulator array 4 is output to the optical signal detection module 5 for monitoring the offset. After receiving the optical signals output by each micro-ring modulator (or the optical signals output by each micro-ring modulator through its corresponding coupler), the optical signal detection module 5 can obtain the current optical signal tag within the signal. Then, based on the original optical signal tag of the laser 2 corresponding to that micro-ring modulator, it can determine the offset of the micro-ring modulator's operating wavelength.

[0025] In one implementation, the optical tag generation module is a low-frequency signal generator; Each low-frequency signal generator is used to generate multiple low-frequency periodic perturbation signals with different frequencies and amplitudes; each low-frequency periodic perturbation signal is an optical signal tag and corresponds to a laser.

[0026] In other words, in practical applications, a low-frequency signal generator can be used to generate low-frequency periodic perturbation signals with adjustable frequencies and amplitudes (e.g., frequency range 1~1MHz). This low-frequency perturbation signal serves as an independent identifier for each optical wavelength channel (i.e., each laser). The output port of each low-frequency signal generator is connected to a modulation port of a laser driver, and the signal is applied to the laser driver via current modulation. The electrical modulator of the laser driver modulates the received low-frequency periodic perturbation signal into a small-amplitude modulation in the optical domain, causing the laser output light source signal to generate a periodic modulation with a very small amplitude. That is, the light source signal output by laser 2 is superimposed with a modulation signal frequency with a unique wavelength identifier, thereby forming a dynamic tag unique to each laser wavelength channel (i.e., realizing a unique wavelength-tag identifier) ​​to better mark the light source signal output by each laser 2.

[0027] In one implementation, such as Figure 2 As shown, the optical signal detection module 5 includes: The photoelectric conversion module 51, which is connected to each micro-ring modulator in a one-to-one manner, is used to convert the optical signal output by the corresponding micro-ring modulator into an electrical signal. The filter module 52, which is connected to each photoelectric conversion module 51 in a one-to-one manner, is used to filter the electrical signal using the target frequency to obtain the filtered electrical signal; the target frequency is set based on the frequency of the optical signal tag of the target laser corresponding to the micro-ring modulator. The signal processing module 53, which is connected to each filter module 52 in a one-to-one manner, is used to determine the offset of the operating wavelength of the micro-ring modulator based on the filtered electrical signal.

[0028] It is understood that the optical signal detection module 5 in this embodiment can be configured with a set of photoelectric conversion modules 51, filter modules 52, and signal processing modules 53 for each micro-ring modulator. The photoelectric conversion module 51 converts the optical signal output by the corresponding micro-ring modulator into an electrical signal, which is then transmitted to the corresponding filter module 52. The filter module 52 filters the electrical signal using a pre-set target frequency to obtain a filtered electrical signal. The target frequency can be set according to the frequency of the optical signal tag of the target laser corresponding to the corresponding micro-ring modulator, or the target frequency is the frequency of the optical signal tag of the target laser corresponding to the corresponding micro-ring modulator. For example, if the frequency of the optical signal tag corresponding to laser 1 is 1500 Hz, the target frequency of the filter module 51 on the optical channel corresponding to laser 1 can also be set to 1500 Hz. This allows an electrical signal with the same target frequency to be obtained from the electrical signal. The filtered electrical signal is then sent to the signal processing module 53, which determines the offset of the operating wavelength of the micro-ring modulator based on the filtered electrical signal, thereby improving the monitoring accuracy.

[0029] In addition, the filter module 52 in this embodiment can filter the photocurrent or the photovoltage converted by the transimpedance amplifier. On the one hand, it is used to filter out the mapping of the low-frequency optical tag perturbation signal at the micro-ring coupling end, and on the other hand, it is used to filter the optical signal at the micro-ring coupling end.

[0030] In one embodiment, the signal processing module 53 is specifically used to determine whether the amplitude of the filtered electrical signal is within the corresponding preset amplitude range. If so, the operating wavelength of the micro-ring modulator has not shifted; if not, the operating wavelength of the micro-ring modulator has shifted.

[0031] Specifically, a preset amplitude range can be set based on the amplitude of the original optical tag signal corresponding to the laser 2 for each signal processing module 53. After obtaining the filtered electrical signal transmitted by the filter module 52, the signal processing module 53 can obtain the corresponding preset amplitude range and then compare the amplitude of the filtered electrical signal with the preset amplitude range. If the amplitude of the filtered electrical signal is within the preset amplitude range, it means that the optical signal transmitted in the micro-ring modulator is the optical signal emitted by the corresponding laser 2 at the preset wavelength, and the operating wavelength of the micro-ring modulator has not shifted. If the amplitude of the filtered electrical signal is not within the preset amplitude range, it means that the optical signal transmitted in the micro-ring modulator is not the optical signal emitted by the corresponding laser 2 at the preset wavelength, and the operating wavelength of the micro-ring modulator has shifted. In this embodiment, setting the preset amplitude range of the corresponding signal processing module 53 based on the amplitude of the optical tag signal corresponding to the laser 2 can improve the monitoring accuracy of optical channel offset.

[0032] In one implementation, such as Figure 2 and Figure 3 As shown, the system may also include: a control module 6 connected to the signal processing module 53 and a micro heater 7 connected to the control module 6, which corresponds to each micro ring modulator. The control module 6 is used to adjust the power of the micro heater 7 corresponding to the micro ring modulator when the operating wavelength of the corresponding micro ring modulator is deviated based on the output signal of the signal processing module 53.

[0033] It is understood that, in order to adjust the operating wavelength of the micro-ring modulator in this embodiment, a control module 6 can be provided. This control module 6 can calculate the required control compensation amount based on the optical tag detection result, and then drive the power of the micro heater (i.e., the thermo-optical tuning module) integrated in the micro-ring modulator to adjust the power, thereby performing real-time thermal control compensation on the micro-ring modulator and accurately adjusting the resonant wavelength of the micro-ring modulator to the target wavelength channel or near the target wavelength channel. In addition, the control module 6 can also set the perturbation signal (such as the target frequency and preset amplitude range) generated by the signal processing module 53.

[0034] In practical applications, the control module 6 runs on an MCU or FPGA. That is, it can receive the optical tag determination results (i.e., the offset determination results) of each channel output by the signal processing modules 53, and based on these results, perform thermal tuning control on the micro-heater, driving the resonant wavelength of the corresponding micro-ring modulator to be adjusted to the target channel wavelength or a set point near that channel wavelength. In practical applications, multiple optical tag signals corresponding to different light source wavelength channels can also be set.

[0035] In one implementation, please refer to Figure 4 and Figure 6 The photoelectric conversion module 51 includes a first photodetector and a second photodetector, and the filter module 52 includes a first filter and a second filter; wherein, the input terminal of the first photodetector is connected to the input terminal of the micro-ring modulator, the output terminal of the first photodetector is connected to the input terminal of the first filter, the output terminal of the first filter is connected to the first input terminal of the signal processing module 53, the input terminal of the second photodetector is connected to the output terminal of the micro-ring modulator, the output terminal of the second photodetector is connected to the input terminal of the second filter, and the output terminal of the second filter is connected to the second input terminal of the signal processing module 53; The first photodetector is used to convert the input optical signal of the micro-ring modulator into a first electrical signal; The second photodetector is used to convert the output optical signal of the micro-ring modulator into a second electrical signal; The first filter is used to filter the first electrical signal to obtain the first optical power signal; The second filter is used to filter the second electrical signal to obtain the second optical power signal and the optical tag signal; The signal processing module is used to determine the offset of the operating wavelength of the micro-ring modulator based on the optical tag signal and generate an offset result signal, and to normalize the second optical power signal according to the first optical power signal to obtain the normalized optical power signal. The control module 6 is used to adjust the power of the micro heater 7 corresponding to the micro ring modulator based on the normalized optical power signal when the operating wavelength of the corresponding micro ring modulator is offset based on the offset result signal.

[0036] It should be noted that, in this embodiment, the first photodetector can acquire the input optical signal from the input end of the micro-ring modulator. Specifically, it can receive the input optical signal from the micro-ring modulator through a coupler connected to the micro-ring modulator, and convert the input optical signal from the micro-ring modulator into a first electrical signal and send it to the first filter. The first filter filters the first electrical signal to obtain a first optical power signal, which is then sent to the signal processing module. The second photodetector can acquire the output optical signal from the output end of the micro-ring modulator. Specifically, it can receive the output optical signal from the micro-ring modulator through a coupler connected to the micro-ring modulator, and convert the output optical signal from the micro-ring modulator into a second electrical signal. The second electrical signal is then sent to the second filter, which filters the second electrical signal to obtain a second optical power signal and an optical tag signal. The second optical power signal and the optical tag signal are then sent to the signal processing module. The signal processing module determines the offset of the operating wavelength of the micro-ring modulator based on the optical tag signal and generates an offset result signal. It then normalizes the second optical power signal based on the first optical power signal to obtain a normalized optical power signal.

[0037] In practical applications, such as Figure 5 and Figure 6 The first filter shown can be a first low-pass filter or a band-pass filter. The second filter can be a first band-pass filter to filter the second electrical signal to obtain the second optical power signal and the optical tag signal. Alternatively, it can be a second low-pass filter and a second band-pass filter. The second electrical signal is filtered by the second low-pass filter to obtain the second optical power signal, and the second electrical signal is filtered by the second band-pass filter to obtain the optical tag signal.

[0038] That is, by using the first filter and the second filter, on the one hand, the optical tag signal coupled out from the output port of the micro-ring modulator can be filtered out by the bandpass filter to complete the extraction of the optical tag; on the other hand, the optical signal output from the micro-ring coupling end is filtered to obtain the wavelength matching state of the micro-ring modulator.

[0039] In one embodiment, the system may further include a first transimpedance amplifier and a second transimpedance amplifier; wherein the input terminal of the first transimpedance amplifier is connected to the output terminal of the first photodetector, the output terminal of the first transimpedance amplifier is connected to the input terminal of the first filter, the input terminal of the second transimpedance amplifier is connected to the output terminal of the second photodetector, and the output terminal of the second transimpedance amplifier is connected to the input terminal of the second filter.

[0040] In other words, the first and second photodetectors in this embodiment are used to achieve photoelectric conversion. Specifically, through the optical coupler and photodetector connected to each micro-ring modulator, a portion of the output light from each micro-ring modulator in the micro-ring modulator array can be coupled out and converted into a current signal, which is then converted into a corresponding voltage signal after passing through the corresponding transimpedance amplifier. That is, the first transimpedance amplifier converts the first electrical signal sent by the first photodetector into a first voltage signal, the second transimpedance amplifier converts the second electrical signal sent by the second photodetector into a second voltage signal, the first filter filters the first voltage signal to obtain a first optical power signal, and the second filter filters the second voltage signal to obtain a second optical power signal and an optical tag signal.

[0041] In addition, in the embodiments of this application Figure 5 The converted electrical signal from coupling port 1 is filtered by a first low-pass filter to obtain the average optical power signal intensity, while the converted electrical signal from coupling port 2 is filtered by a second low-pass filter to also obtain the average optical power signal intensity. Simultaneously, the output signal from this path is filtered by a band-pass filter for optical tag signal extraction. This specific implementation scheme is suitable for situations where low-frequency optical tag perturbation signals are modulated onto the wavelength of the light source. Figure 6 In this implementation method, the converted electrical signals coupled from the input and output ends of the micro-ring are both filtered by a bandpass filter to extract the light intensity changes carrying only the optical tag signal. The two electrical signals are then input into a divider to directly calculate the dimensionless light intensity value, which can also be used to characterize the shift in the micro-ring's resonant wavelength. This specific implementation scheme is suitable for situations where low-frequency optical tag perturbation signals are modulated onto the light source power.

[0042] In one implementation, such as Figure 5 and Figure 6 As shown, the signal processing module 53 includes a divider, a first analog-to-digital converter (ADC), a second ADC, and an optical tag detection module. The first input terminal of the divider is connected to the output terminal of the first filter, the second input terminal of the divider is connected to the first sub-output terminal of the second filter, the output terminal of the divider is connected to the input terminal of the first ADC, the output terminal of the first ADC is connected to the first input terminal of the control module, the input terminal of the second ADC is connected to the second sub-output terminal of the second filter, the output terminal of the second ADC is connected to the input terminal of the optical tag detection module, and the output terminal of the optical tag detection module is connected to the second input terminal of the control module. The divider is used to normalize the second optical power signal based on the first optical power signal to obtain the normalized optical power signal. The first analog-to-digital converter is used to convert the normalized optical power signal into the corresponding optical power digital signal. The second analog-to-digital converter is used to convert the optical tag signal into the corresponding optical tag digital signal. The optical tag detection module is used to determine the offset of the operating wavelength of the micro-ring modulator by the digital signal of the optical tag and generate an offset result signal.

[0043] It should also be noted that, such as Figure 5 As shown, the signal processing module 53 includes two core functions: coupled optical signal preprocessing and optical tag detection. The optical signals output from the coupler output ports (coupled port 1 and coupled port 2, i.e., the input and through ports) of the aforementioned micro-ring modulator are converted by the photoelectric conversion module to output corresponding first voltage signals, second voltage signals, and optical tag signals. These signals are then input to the signal processing module 53. The first and second voltage signals are simultaneously input to a divider for normalization to characterize their resonant wavelength state. The optical tag signal is input to the second analog-to-digital converter and then to the optical tag detection module for detection to obtain the offset state between the micro-ring resonant wavelength and the corresponding preset laser wavelength channel. The optical power digital signal output from the first analog-to-digital converter and the offset result signal output from the optical tag detection module are both input to the control module.

[0044] In this embodiment, the optical tag detection module utilizes the periodic characteristics of the optical tag to detect and determine the wavelength matching status of different optical channels. For example, it compares the amplitude of the optical tag extracted by the bandpass filter with a preset amplitude range to determine the wavelength matching status of the channel. If the amplitude of the optical tag signal is not within the preset amplitude range, it is determined to be a mismatch, meaning there is no corresponding optical signal tag. If the amplitude of the optical tag signal is within the preset amplitude range, it is determined to be a match, meaning there is a corresponding optical signal tag. The preset threshold range can be based on a preset threshold value. To determine this, the preset threshold can be obtained through calibration. Specifically, under the condition of superimposing a perturbation light tag signal on a specific light source signal, the power operating range of the corresponding micro-ring integrated heater is gradually increased, and the maximum amplitude of the light tag voltage after the bandpass filter is read and recorded. Then, a preset threshold is set based on the maximum amplitude value, such as ,in The signal processing module 53 can be configured based on experience and can be implemented using an MCU or FPGA.

[0045] Specifically, the optical tag detection module is responsible for determining the validity of the optical tag signal and triggering wavelength lock reset. The signal, after photocurrent / voltage conversion and bandpass filtering, contains only the low-frequency AC component of the optical tag, providing a clean signal input for subsequent optical tag detection. Figure 7As shown, the bandpass filter accurately extracts the unique low-frequency optical tag signal from the mixed electrical signal and filters out noise and interference from other frequency signals to obtain the corresponding optical tag signal. This signal is then processed by a second digital-to-analog converter to obtain the digital signal of the optical tag. The optical tag detection module performs peak detection on this digital signal, extracting the corresponding peak value, i.e., extracting the DC amplitude from the AC signal. This amplitude is the detected optical tag signal strength. The extracted peak value is compared with a preset amplitude range (where the preset amplitude range is determined based on a preset amplitude, which can be the effective minimum amplitude of the optical tag). If the peak value is within the preset amplitude range (e.g., the judgment condition could be N consecutive times within the threshold range), the optical tag signal is valid, indicating that the operating wavelength of the micro-ring modulator matches the channel wavelength. If the extracted peak value is outside the preset amplitude range (e.g., the judgment condition could be M consecutive times outside the threshold range), the optical tag is invalid, indicating that the operating wavelength of the micro-ring has deviated from the matched channel wavelength. It should be noted that if the optical tag is determined to be invalid, it indicates that there is a deviation in the operating wavelength of the micro-ring modulator. At this time, the control module can adjust the power of the micro heater corresponding to the micro-ring modulator. For example, it can increase or decrease the power by a preset step size based on the current power and perform the next round of detection until the optical tag is detected to be valid and the normalized optical power signal meets the preset optical power requirements.

[0046] Additionally, you can refer to Figure 8 The system can pre-scan the power operating range of the microheater step by step and determine the target photovoltage value of the microring modulator corresponding to different power levels. It records the power of the microheater corresponding to each target photovoltage value of the microring modulator, completes the target value initialization, and then obtains the current normalized optical power signal during the detection process. The photovoltage measurement value corresponding to the optical power signal is compared with the target photovoltage value obtained in the initialization stage. If the difference between the photovoltage measurement value and the target photovoltage value reaches the preset voltage difference threshold, the power of the microheater can be increased or decreased.

[0047] Therefore, this application sets up a corresponding optical tag generation module for each laser. Each optical tag generation module generates an optical signal tag that uniquely corresponds to the laser. Each laser corresponds to an optical channel. The laser uses the corresponding optical signal tag to modulate the emitted light source signal to obtain a modulated light source signal. The optical coupler performs wavelength division multiplexing on the received modulated light source signals and couples them to the same waveguide for transmission to the micro-ring modulator array. Each micro-ring modulator in the micro-ring modulator array can modulate its own harmonics to match the wavelength of the light signal emitted by the corresponding laser, thereby realizing the transmission of the light signal that matches its own tuned wavelength. After the optical signal detection module obtains the light signal output by each micro-ring modulator, it can accurately determine the offset of the working wavelength of the corresponding micro-ring modulator based on the current optical signal tag in the light signal and the optical signal tag of the target laser corresponding to the micro-ring modulator. In this application, the optical signal tag uniquely corresponding to the laser is integrated with the light source signal emitted by the laser and transmitted to the micro-ring modulator array through an optical coupler and a waveguide. Then, by detecting and analyzing the current optical signal tag in the optical signal output by each micro-ring modulator in the micro-ring modulator array, the offset of the operating wavelength of the corresponding micro-ring modulator can be determined, thereby improving the accuracy of detecting the offset of the operating wavelength of the micro-ring modulator.

[0048] In other words, the embodiments of this application solve the channel wavelength mismatch problem in wavelength division multiplexing systems based on micro-ring modulators in an integrated, low-cost, real-time dynamic manner.

[0049] Based on the above embodiments, please refer to Figure 9 This application also provides a method for monitoring the optical channel of a micro-ring wavelength division multiplexing system, including: S110: Obtain the optical signal tag corresponding to each laser.

[0050] S120: Each optical signal tag is used to modulate the light source signal generated by the corresponding laser to obtain the modulated light source signal.

[0051] S130: Perform wavelength division multiplexing on each modulated light source signal, and transmit the wavelength division multiplexed optical signal to the micro-ring modulation array through a waveguide.

[0052] S140: For each micro-ring modulator in the micro-ring modulation array, acquire the optical signal output by the micro-ring modulator.

[0053] S150: Determine the offset of the operating wavelength of the micro-ring modulator based on the current optical signal tag in the optical signal and the optical signal tag of the target laser corresponding to the micro-ring modulator.

[0054] It should be noted that the optical channel monitoring method of the micro-ring wavelength division multiplexing system in this application embodiment has the same beneficial effects as the micro-ring wavelength division multiplexing system in the above embodiment. For a detailed description of the micro-ring wavelength division multiplexing system involved in this application, please refer to the above embodiments. This application will not repeat the description here.

[0055] Based on the above embodiments, this application provides an optical channel monitoring device for a micro-ring wavelength division multiplexing system. Please follow... Figure 10 The device may include: The first acquisition module 11 is used to acquire optical signal tags that correspond one-to-one with each laser. Modulation module 12 is used to modulate the light source signal generated by the corresponding laser using each optical signal tag to obtain the modulated light source signal; Multiplexing module 13 is used to perform wavelength division multiplexing on each modulated light source signal and transmit the wavelength division multiplexed optical signal to the micro-ring modulation array through a waveguide; The second acquisition module 14 is used to acquire the optical signal output by each micro-ring modulator in the micro-ring modulation array. Analysis module 15 is used to determine the offset of the operating wavelength of the micro-ring modulator based on the current optical signal tag in the optical signal and the optical signal tag of the target optical channel corresponding to the micro-ring modulator.

[0056] It should be noted that the optical channel monitoring device of the micro-ring wavelength division multiplexing system in this application embodiment has the same beneficial effects as the micro-ring wavelength division multiplexing system in the above embodiments, and for a detailed description of the micro-ring wavelength division multiplexing system involved in this application, please refer to the above embodiments, which will not be repeated here.

[0057] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0058] It should also be noted that, in this specification, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0059] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A micro-ring wavelength division multiplexing system, characterized in that, include: Multiple optical tag generation modules are used to generate optical signal tags that correspond one-to-one with each laser; A laser connected to each of the optical tag generation modules is used to modulate the light source signal generated by itself using the received optical signal tag to obtain the modulated light source signal. An optical coupler connected to each of the lasers is used to perform wavelength division multiplexing on each of the modulated light source signals and transmit the wavelength division multiplexed optical signals to the micro-ring modulation array through a waveguide; A microring modulator array is used to transmit optical signals that are matched to their own tuning wavelengths through individual microring modulators; An optical signal detection module is used to acquire the optical signals output by each of the micro-ring modulators, and to determine the offset of the operating wavelength of the micro-ring modulator based on the current optical signal tag in the optical signal and the optical signal tag of the target laser corresponding to the micro-ring modulator.

2. The micro-ring wavelength division multiplexing system according to claim 1, characterized in that, The optical tag generation module is a low-frequency signal generator; Each low-frequency signal generator is used to generate multiple low-frequency periodic perturbation signals with different frequencies and amplitudes; each of the low-frequency periodic perturbation signals is an optical signal tag and corresponds to a laser.

3. The micro-ring wavelength division multiplexing system according to claim 2, characterized in that, The optical signal detection module includes: A photoelectric conversion module, which is connected to each micro-ring modulator in a one-to-one manner, is used to convert the optical signal output by the corresponding micro-ring modulator into an electrical signal. A filter module, connected one-to-one with each of the photoelectric conversion modules, is used to filter the electrical signal using a target frequency to obtain a filtered electrical signal; the target frequency is set based on the frequency of the optical signal tag of the target laser corresponding to the micro-ring modulator; A signal processing module, which is connected to each of the filter modules in a one-to-one manner, is used to determine the offset of the operating wavelength of the micro-ring modulator based on the filtered electrical signal.

4. The micro-ring wavelength division multiplexing system according to claim 2, characterized in that, The signal processing module is specifically used to determine whether the amplitude of the filtered electrical signal is within the corresponding preset amplitude range. If it is, the operating wavelength of the micro-ring modulator has not shifted; if not, the operating wavelength of the micro-ring modulator has shifted.

5. The micro-ring wavelength division multiplexing system according to claim 3, characterized in that, Also includes: A control module connected to the signal processing module and a micro heater connected to the control module, corresponding to each of the micro-ring modulators; The control module is used to adjust the power of the micro heater corresponding to the micro ring modulator when the operating wavelength of the corresponding micro ring modulator is deviated based on the output signal of the signal processing module.

6. The micro-ring wavelength division multiplexing system according to claim 5, characterized in that, The photoelectric conversion module includes a first photodetector and a second photodetector, and the filter module includes a first filter and a second filter; wherein, the input terminal of the first photodetector is connected to the input terminal of the micro-ring modulator, the output terminal of the first photodetector is connected to the input terminal of the first filter, the output terminal of the first filter is connected to the first input terminal of the signal processing module, the input terminal of the second photodetector is connected to the output terminal of the micro-ring modulator, the output terminal of the second photodetector is connected to the input terminal of the second filter, and the output terminal of the second filter is connected to the second input terminal of the signal processing module; The first photodetector is used to convert the input optical signal of the micro-ring modulator into a first electrical signal; The second photodetector is used to convert the output optical signal of the micro-ring modulator into a second electrical signal; The first filter is used to filter the first electrical signal to obtain the first optical power signal; The second filter is used to filter the second electrical signal to obtain the second optical power signal and the optical tag signal; The signal processing module is used to determine the offset of the operating wavelength of the micro-ring modulator based on the optical tag signal and generate an offset result signal, and to normalize the second optical power signal according to the first optical power signal to obtain a normalized optical power signal. The control module is used to adjust the power of the micro heater corresponding to the micro ring modulator based on the normalized optical power signal when the operating wavelength of the corresponding micro ring modulator is determined to be offset based on the offset result signal.

7. The micro-ring wavelength division multiplexing system according to claim 6, characterized in that, The signal processing module includes a divider, a first analog-to-digital converter (ADC), a second ADC, and an optical tag detection module. The first input terminal of the divider is connected to the output terminal of the first filter, the second input terminal of the divider is connected to the first sub-output terminal of the second filter, the output terminal of the divider is connected to the input terminal of the first ADC, the output terminal of the first ADC is connected to the first input terminal of the control module, the input terminal of the second ADC is connected to the second sub-output terminal of the second filter, the output terminal of the second ADC is connected to the input terminal of the optical tag detection module, and the output terminal of the optical tag detection module is connected to the second input terminal of the control module. The divider is used to normalize the second optical power signal based on the first optical power signal to obtain a normalized optical power signal. The first analog-to-digital converter is used to convert the normalized optical power signal into a corresponding optical power digital signal. The second analog-to-digital converter is used to convert the optical tag signal into a corresponding optical tag digital signal; The optical tag detection module is used to determine the offset of the operating wavelength of the micro-ring modulator by the digital signal of the optical tag and generate an offset result signal.

8. The micro-ring wavelength division multiplexing system according to claim 6, characterized in that, Also includes: A first transimpedance amplifier and a second transimpedance amplifier; wherein the input terminal of the first transimpedance amplifier is connected to the output terminal of the first photodetector, the output terminal of the first transimpedance amplifier is connected to the input terminal of the first filter, the input terminal of the second transimpedance amplifier is connected to the output terminal of the second photodetector, and the output terminal of the second transimpedance amplifier is connected to the input terminal of the second filter.

9. A method for monitoring the optical channel of a micro-ring wavelength division multiplexing system, characterized in that, include: Obtain the optical signal tag that corresponds to each laser; Each of the aforementioned optical signal tags modulates the light source signal generated by the corresponding laser to obtain a modulated light source signal; Each of the modulated light source signals is wavelength divided and multiplexed, and the wavelength divided and multiplexed optical signal is transmitted to the micro-ring modulation array through a waveguide; For each micro-ring modulator in the micro-ring modulation array, the optical signal output by the micro-ring modulator is acquired; The offset of the operating wavelength of the micro-ring modulator is determined based on the current optical signal tag in the optical signal and the optical signal tag of the target laser corresponding to the micro-ring modulator.

10. An optical channel monitoring device for a micro-ring wavelength division multiplexing system, characterized in that, include: The first acquisition module is used to acquire optical signal tags that correspond one-to-one with each laser. A modulation module is used to modulate the light source signal generated by the corresponding laser using each of the optical signal tags to obtain a modulated light source signal. The multiplexing module is used to perform wavelength division multiplexing on each of the modulated light source signals and transmit the wavelength division multiplexed optical signal to the micro-ring modulation array through a waveguide. The second acquisition module is used to acquire the optical signal output by each micro-ring modulator in the micro-ring modulation array. The analysis module is used to determine the offset of the operating wavelength of the micro-ring modulator based on the current optical signal tag in the optical signal and the optical signal tag of the target optical channel corresponding to the micro-ring modulator.

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