Micro-ring resonator thermal wavelength locking system and method, terminal

Abstract

This invention provides a microring resonator thermally modulated wavelength locking system, method, and terminal. The thermally modulated wavelength locking system includes: several wavelength control channels, each containing a microring resonator, used to resonate with an optical signal of a specific wavelength to output an analog electrical signal, and also thermally tuned based on a digital compensation signal for wavelength locking; a multiplexer, coupled to the output of each wavelength control channel, which, under the control of a control module, selects one output from the received analog electrical signals; an analog-to-digital converter, coupled to the output of the multiplexer, converts the received analog electrical signals into digital electrical signals for output; and a control module, coupled to the output of the analog-to-digital converter, which evaluates the resonant state and thermal drift direction of the microring resonator in the corresponding wavelength control channel based on the received digital electrical signal and generates a corresponding digital compensation signal. This invention solves many problems of traditional wavelength locking schemes, such as large area, high power consumption, and complex wiring.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, and in particular to a microring resonator thermally modulated wavelength locking system, method, and terminal. Background Technology

[0002] In applications such as optical interconnects, data center communications, high-performance computing, and high-speed inter-chip transmission, wavelength division multiplexing (WDM) technology can simultaneously carry multiple optical signals of different wavelengths in a single optical waveguide or optical fiber, thereby significantly improving the transmission capacity and bandwidth density of the system. Microring resonators, due to their compact size, ease of large-scale integration, and excellent wavelength selectivity, have become one of the essential components in on-chip WDM filtering, multiplexing, and demultiplexing systems.

[0003] However, the center resonant wavelength of a microring resonator is highly susceptible to manufacturing process deviations and environmental temperature disturbances. To ensure the stability and reliability of the communication link, a thermally tuned loop is typically used to lock the wavelength of each stage of the microring resonator. In traditional solutions, the wavelength locking system is a point-to-point independent control architecture, where each microring resonator corresponds to a dedicated analog-to-digital converter.

[0004] With the increasing number of channels and integration density in WDM systems, this point-to-point independent control architecture is facing severe hardware resource bottlenecks. As a core module in mixed-signal integrated circuits, the analog-to-digital converter (ADC) has a complex internal structure, requiring significant physical layout area and exhibiting high static and dynamic power consumption. In multi-channel parallel operation scenarios, deploying a large number of independent ADCs leads to the entire optoelectronic integrated chip area being severely squeezed by peripheral control circuits, reducing the integration density of core photonic devices and significantly increasing chip fabrication costs.

[0005] Furthermore, the parallel operation of numerous analog-to-digital converters not only leads to a sharp increase in system power consumption but also makes the signal routing within the chip extremely complex. Multiple parallel analog high-frequency traces are highly susceptible to introducing severe inter-channel electrical crosstalk within a limited space, resulting in increased sampling noise and decreased accuracy of the analog-to-digital converters, ultimately affecting the stability and accuracy of wavelength locking. This is especially true in high-density optical interconnect scenarios where area budgets are extremely critical, where traditional solutions waste area and are more prone to electrical crosstalk.

[0006] Therefore, how to break through the physical limitations of traditional solutions and significantly reduce the number of core hardware resources such as analog-to-digital converters while ensuring the wavelength locking accuracy and response speed of multi-channel micro-ring resonators, thereby effectively reducing area consumption, lowering overall power consumption and simplifying wiring complexity, remains one of the urgent problems to be solved in existing optoelectronic integration technology.

[0007] It should be noted that the above description of the technical background is only for the purpose of providing a clear and complete explanation of the technical solutions of the present invention and facilitating understanding by those skilled in the art. It should not be assumed that the above technical solutions are known to those skilled in the art simply because they have been described in the background section of this invention. Summary of the Invention

[0008] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a micro-ring resonator thermally modulated wavelength locking system, method, and terminal to solve many problems of traditional wavelength locking schemes, such as large area, high power consumption, and complex wiring.

[0009] To achieve the above and other related objectives, this invention provides a microring resonator thermally modulated wavelength locking system, comprising several wavelength modulation channels, a multiplexer, an analog-to-digital converter, and a control module, wherein:

[0010] The wavelength control channel includes a micro-ring resonator, which is used to resonate with optical signals of a specific wavelength to output an analog electrical signal, and also performs thermal tuning based on a digital compensation signal to lock the wavelength.

[0011] The multiplexer is coupled to the output of each wavelength modulation channel, and under the control of the control module, it selects one output from several received analog electrical signals.

[0012] The analog-to-digital converter is coupled to the output of the multiplexer and is used to convert the received analog electrical signal into a digital electrical signal for output.

[0013] The control module is coupled to the output of the analog-to-digital converter. Based on the received digital electrical signal, it evaluates the resonance state and thermal drift direction of the micro-ring resonator in the corresponding wavelength control channel and generates the corresponding digital compensation signal.

[0014] Optionally, the analog-to-digital converter is a current-mode analog-to-digital converter; the wavelength modulation channel further includes a photodetector and a modulation heating module, wherein:

[0015] The micro-ring resonator resonates in response to optical signals of a specific wavelength and outputs a monitoring optical signal.

[0016] The photodetector is coupled to the output of the microring resonator and is used to convert the received monitoring optical signal into an analog current signal output.

[0017] The heating control module is coupled to the output of the control module and performs thermal tuning on the micro-ring resonator based on the received digital compensation signal.

[0018] Optionally, the analog-to-digital converter is a voltage-type analog-to-digital converter; the wavelength control channel further includes a photodetector, a conversion module, and a control heating module, wherein:

[0019] The micro-ring resonator resonates in response to optical signals of a specific wavelength and outputs a monitoring optical signal.

[0020] The photodetector is coupled to the output of the microring resonator and is used to convert the received monitoring optical signal into an analog current signal output.

[0021] The conversion module is coupled to the output terminal of the photodetector and is used to convert the received analog current signal into an analog voltage signal for output.

[0022] The heating control module is coupled to the output of the control module and performs thermal tuning on the micro-ring resonator based on the received digital compensation signal.

[0023] Optionally, the analog-to-digital converter is a voltage-type analog-to-digital converter; the wavelength control channel further includes a photodetector and a heating control module, wherein:

[0024] The micro-ring resonator resonates in response to optical signals of a specific wavelength and outputs a monitoring optical signal.

[0025] The photodetector is coupled to the output of the microring resonator and is used to convert the received monitoring optical signal into an analog current signal output.

[0026] The heating control module is coupled to the output of the control module and performs thermal tuning on the micro-ring resonator based on the received digital compensation signal.

[0027] The microring resonator thermally modulated wavelength locking system further includes a conversion module coupled between the multiplexer and the analog-to-digital converter, used to convert the received analog current signal into an analog voltage signal for output.

[0028] Optionally, the conversion module is a transimpedance amplifier.

[0029] Optionally, the heating control module includes a digital-to-analog converter and a thermal tuning unit, wherein:

[0030] The digital-to-analog converter is coupled to the output of the control module and is used to convert the received digital compensation signal into an analog tuning signal for output.

[0031] The thermal tuning unit is coupled to the output of the digital-to-analog converter and adjusts the local temperature of the microring resonator based on the analog tuning signal to regulate its effective refractive index and center resonant wavelength.

[0032] Optionally, the heating control module further includes a drive unit coupled between the digital-to-analog converter and the thermal tuning unit.

[0033] The present invention also provides a terminal comprising the microring resonator thermally modulated wavelength locking system as described in any of the above claims.

[0034] Optionally, the terminal is a sending end.

[0035] Optionally, the terminal is a receiving end.

[0036] The present invention also provides a method for thermally modulated wavelength locking of a microring resonator, comprising:

[0037] S1, several wavelength control channels resonate with optical signals of their respective specific wavelengths to output several analog electrical signals;

[0038] S2, the multiplexer selects one output from several analog electrical signals in a time-division multiplexing manner;

[0039] S3, the analog-to-digital converter converts the received analog electrical signal into a digital electrical signal;

[0040] S4, the control module evaluates the resonance state and thermal drift direction of the micro-ring resonator in the corresponding wavelength control channel based on the received digital electrical signal, and generates the corresponding digital compensation signal to be output to the corresponding wavelength control channel for thermal tuning;

[0041] S5, jump to S2 to evaluate the next wavelength control channel and output, until all wavelength control channels have been evaluated and output.

[0042] Optionally, it also includes: S6, repeating S1~S5 at least once until wavelength locking of the micro-ring resonators in all wavelength control channels is completed.

[0043] Optionally, the time-division multiplexing method is a time-division multiplexing polling control method.

[0044] As described above, the microring resonator thermally modulated wavelength locking system, method, and terminal of the present invention have the following beneficial effects:

[0045] 1. By introducing a multiplexer, a multi-channel time-division shared architecture is constructed, in which multiple wavelength control channels share a single analog-to-digital converter, thereby reducing the number of analog-to-digital converters used by a factor of two, significantly reducing the physical area overhead of the entire optoelectronic integrated chip, reducing the cost of chip fabrication, and perfectly matching the trend of integration evolution of high-density optical interconnect systems.

[0046] 2. By utilizing the time-division multiplexing mechanism of the analog-to-digital converter, the power consumption problem caused by the parallel operation of multiple analog-to-digital converters is avoided, significantly reducing the overall static leakage power consumption and dynamic conversion power consumption of the system. This extremely low power consumption characteristic not only meets the stringent energy efficiency requirements of application scenarios such as green data centers, but also effectively alleviates the "heat island effect" inside the chip, reducing the reverse interference of local irregular heat sources on the temperature stability of the micro-ring resonator itself from the physical source.

[0047] 3. By significantly reducing the number of core components such as analog-to-digital converters, the complexity of signal routing inside the chip is greatly simplified; the convergence and reduction of multiple high-frequency analog traces not only effectively reduces the complexity of layout routing and physical space constraints, but also fundamentally weakens the problem of electrical crosstalk and noise coupling between channels that are easily caused by multi-channel parallel high-frequency traces, thereby improving the signal integrity and anti-interference capability of the closed-loop sampling link.

[0048] 4. By utilizing the physical difference between the high-speed characteristics of the electrical domain and the slow characteristics of the thermal domain, high-precision wavelength locking and fast offset recovery capabilities can still be maintained without sacrificing locking performance while significantly reducing hardware resources and power consumption.

[0049] 5. The multi-channel time-division sharing architecture of this invention endows optoelectronic systems with strong channel expansion capabilities and scalability potential. Facing the future demand for wavelength division multiplexing with higher channel capacity (such as expansion to 16 channels, 32 channels and above), it is only necessary to expand the analog input ports of the front-end multiplexer and the corresponding control timing code, without having to stack a huge analog-to-digital converter resource in a linear proportion. This greatly reduces the hardware design threshold for closed-loop control of large-scale micro-ring resonators and has significant advantages in terms of device design freedom, system feasibility and engineering application adaptability. Attached Figure Description

[0050] Figure 1 This is a schematic diagram of a micro-ring resonator thermally modulated wavelength locking system in Embodiment 1 of the present invention.

[0051] Figure 2 This is a schematic diagram of a micro-ring resonator thermally modulated wavelength locking system in Embodiment 2 of the present invention.

[0052] Figure 3 for Figure 2 The diagram shows a specific implementation of a microring resonator thermally modulated wavelength locking system.

[0053] Figure 4 This is a schematic diagram of a micro-ring resonator thermally modulated wavelength locking system in Embodiment 3 of the present invention.

[0054] Figure 5 for Figure 4The diagram shows a specific implementation of a microring resonator thermally modulated wavelength locking system.

[0055] Component labeling: 100-Micro-ring resonator thermally tuned wavelength locking system, 110-Wavelength control channel, 111-Micro-ring resonator, 112-Photodetector, 113-Controlled heating module, 1131-Digital-to-analog converter, 1132-Thermal tuning unit, 1133-Drive unit, 114-Conversion module, 120-Multiplexer, 130-Analog-to-digital converter, 140-Control module. Detailed Implementation

[0056] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0057] Please see Figures 1 to 5 It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of the present invention. Therefore, the illustrations only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the shape, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0058] Example 1

[0059] like Figure 1 As shown, this embodiment provides a microring resonator thermally modulated wavelength locking system 100, including several wavelength modulation channels 110, a multiplexer 120, an analog-to-digital converter 130 and a control module 140.

[0060] The wavelength modulation channel 110 is used to resonate with an optical signal of a specific wavelength to output an analog electrical signal (such as an analog current signal), and also to perform thermal tuning based on a digital compensation signal for wavelength locking. In one embodiment, the wavelength modulation channel 110 includes a microring resonator 111, and further includes a photodetector 112 and a modulated heating module 113.

[0061] The microring resonator 111 is used to resonate with an optical signal of a specific wavelength and output a monitoring optical signal. Specifically, the microring resonator 111 includes a microring structure and an output structure, wherein the microring structure resonates with an optical signal of a specific wavelength and outputs the obtained monitoring optical signal through the output structure.

[0062] It should be noted that in each wavelength control channel 110, each micro-ring resonator 111 can correspond to the same input waveguide or different input waveguides, which has no substantial impact on this embodiment; when corresponding to the same input waveguide, each micro-ring resonator 111 can be regarded as a cascaded arrangement.

[0063] Photodetector 112, coupled to the output of microring resonator 111, is used to convert the received monitoring optical signal into an analog current signal output. Specifically, photodetector 112 is a photodiode; however, it can also be any other photoelectric conversion device capable of converting optical signals into current signals, and there is no limitation on this.

[0064] The heating control module 113, coupled to the output of the control module 140, performs thermal tuning on the micro-ring resonator 111 based on the received digital compensation signal. Specifically, the heating control module 113 includes a digital-to-analog converter 1131 and a thermal tuning unit 1132, and further includes a drive unit 1133. Wherein:

[0065] A digital-to-analog converter 1131, coupled to the output of the control module 140, converts the received digital compensation signal into an analog tuning signal for output. A thermal tuning unit 1132, coupled to the output of the digital-to-analog converter 1131, adjusts the effective refractive index and center resonant wavelength of the microring resonator 111 based on the analog tuning signal, thereby achieving thermal tuning of the microring resonator 111. In practical applications, the thermal tuning unit 1132 is a heating resistor, typically located near the microring resonator 111 to facilitate heating of a local area of ​​the microring resonator 111. A driving unit 1133, coupled between the digital-to-analog converter 1131 and the thermal tuning unit 1132, drives the thermal tuning unit 1132 by enhancing the driving capability of the analog tuning signal.

[0066] It should be noted that a specific wavelength can also be called a target wavelength, and wavelength locking means locking the center resonant wavelength of the microring resonator 111 to the target wavelength; for different wavelength control channels 110, the corresponding target wavelengths are different.

[0067] Multiplexer 120, coupled to the output of each wavelength modulation channel 110, selects one output from several received analog electrical signals (such as analog current signals) under the control of control module 140. In one embodiment, multiplexer 120 is a multiplexer-to-one switch, wherein each input is correspondingly coupled to the output of each wavelength modulation channel 110, and the output is coupled to the input of analog-to-digital converter 130. The control terminal receives channel switching commands provided by control module 140 to output the analog current signal of the corresponding wavelength modulation channel 110 based on the channel switching commands.

[0068] Analog-to-digital converter 130, coupled to the output of multiplexer 120, is used to convert received analog electrical signals (such as analog current signals) into digital electrical signals for output. Specifically, analog-to-digital converter 130 is a current-type analog-to-digital converter, which can directly process the analog current signal output from the previous stage without requiring current-to-voltage conversion in the previous stage.

[0069] The control module 140 is coupled to the output of the analog-to-digital converter 130. Based on the received digital electrical signal, it evaluates the resonance state and thermal drift direction of the micro-ring resonator 111 in the corresponding wavelength control channel 110, generates a corresponding digital compensation signal and outputs it to the corresponding wavelength control channel 110 for thermal tuning. Of course, it also provides channel switching instructions to the multiplexer 120.

[0070] In practical applications, the control module 140 typically has several output terminals, each corresponding to one of the wavelength modulation channels 110, to facilitate the directional distribution of the corresponding digital compensation signals back to the corresponding wavelength modulation channels 110. Additionally, the control module 140 also has a control terminal for providing channel switching signals to the multiplexer 120.

[0071] Example 2

[0072] like Figure 2 As shown, this embodiment provides a microring resonator thermally modulated wavelength locking system 100, including several wavelength modulation channels 110, a multiplexer 120, an analog-to-digital converter 130 and a control module 140.

[0073] The wavelength modulation channel 110 is used to resonate with an optical signal of a specific wavelength to output an analog electrical signal (such as an analog voltage signal), and also to perform thermal tuning based on a digital compensation signal for wavelength locking. In one embodiment, the wavelength modulation channel 110 includes a micro-ring resonator 111, and further includes a photodetector 112, a modulation heating module 113, and a conversion module 114.

[0074] The microring resonator 111 is used to resonate with an optical signal of a specific wavelength and output a monitoring optical signal. Specifically, the microring resonator 111 includes a microring structure and an output structure (corresponding to...). Figure 3 The micro-ring structure (including the ring-shaped and broken-line sections) resonates with a specific wavelength of light signal and outputs the obtained monitoring light signal through the output structure.

[0075] It should be noted that in each wavelength control channel 110, each micro-ring resonator 111 can correspond to the same input waveguide or different input waveguides, which has no substantial impact on this embodiment; when corresponding to the same input waveguide, each micro-ring resonator 111 can be regarded as a cascaded arrangement.

[0076] A photodetector 112, coupled to the output of the micro-ring resonator 111, is used to convert the received monitoring optical signal into an analog current signal output. Specifically, as shown... Figure 3 As shown, the photodetector 112 is a photodiode. Of course, it can also be other photoelectric conversion devices that can convert light signals into current signals, and there is no limitation on this.

[0077] The conversion module 114, coupled to the output terminal of the photodetector 112, is used to convert the received analog current signal into an analog voltage signal for output. Specifically, as shown... Figure 3 As shown, conversion module 114 is a transimpedance amplifier that performs current-to-voltage conversion and signal conditioning to output an analog voltage signal with appropriate amplitude. In this embodiment, each conversion module 114 can be calibrated independently. In addition, the multiplexer 120 processes higher amplitude analog voltage signals and has strong anti-interference capabilities.

[0078] The heating control module 113, coupled to the output of the control module 140, performs thermal tuning on the micro-ring resonator 111 based on the received digital compensation signal. Specifically, the heating control module 113 includes a digital-to-analog converter 1131 and a thermal tuning unit 1132, and further includes a drive unit 1133. Wherein:

[0079] A digital-to-analog converter 1131, coupled to the output of the control module 140, converts the received digital compensation signal into an analog tuning signal for output. A thermal tuning unit 1132, coupled to the output of the digital-to-analog converter 1131, adjusts the effective refractive index and center resonant wavelength of the micro-ring resonator 111 based on the analog tuning signal, thereby achieving thermal tuning of the micro-ring resonator 111. In practical applications, such as... Figure 3 As shown, the thermal tuning unit 1132 is a heating resistor, typically located near the microring resonator 111, to heat a local area of ​​the microring resonator 111. The driving unit 1133, coupled between the digital-to-analog converter 1131 and the thermal tuning unit 1132, drives the thermal tuning unit 1132 by enhancing the driving capability of the analog tuning signal.

[0080] It should be noted that a specific wavelength can also be called a target wavelength, and wavelength locking means locking the center resonant wavelength of the microring resonator 111 to the target wavelength; for different wavelength control channels 110, the corresponding target wavelengths are different.

[0081] Multiplexer 120, coupled to the output of each wavelength modulation channel 110, selects one output from several received analog electrical signals (such as analog voltage signals) under the control of control module 140. In one embodiment, multiplexer 120 is a multiplexer-to-one switch, wherein each input is correspondingly coupled to the output of each wavelength modulation channel 110, and the output is coupled to the input of analog-to-digital converter 130. The control terminal receives channel switching commands provided by control module 140 to output the analog voltage signal of the corresponding wavelength modulation channel 110 based on the channel switching commands.

[0082] Analog-to-digital converter 130, coupled to the output of multiplexer 120, is used to convert received analog electrical signals (such as analog voltage signals) into digital electrical signals for output. Analog-to-digital converter 130 is a voltage-type converter, which, compared to current-type converters, offers advantages such as better compatibility, less impact on the preceding stage, and easier integration.

[0083] The control module 140 is coupled to the output of the analog-to-digital converter 130. Based on the received digital electrical signal, it evaluates the resonance state and thermal drift direction of the micro-ring resonator 111 in the corresponding wavelength control channel 110, generates a corresponding digital compensation signal and outputs it to the corresponding wavelength control channel 110 for thermal tuning. Of course, it also provides channel switching instructions to the multiplexer 120.

[0084] In practical applications, the control module 140 typically has several output terminals, each corresponding to one of the wavelength modulation channels 110, to facilitate the directional distribution of the corresponding digital compensation signals back to the corresponding wavelength modulation channels 110. Additionally, the control module 140 also has a control terminal for providing channel switching signals to the multiplexer 120.

[0085] Example 3

[0086] like Figure 4 As shown, this embodiment provides a microring resonator thermally modulated wavelength locking system 100, including several wavelength modulation channels 110, a multiplexer 120, a conversion module 114, an analog-to-digital converter 130, and a control module 140.

[0087] The wavelength modulation channel 110 is used to resonate with an optical signal of a specific wavelength to output an analog electrical signal (such as an analog current signal), and also to perform thermal tuning based on a digital compensation signal for wavelength locking. In one embodiment, the wavelength modulation channel 110 includes a microring resonator 111, and further includes a photodetector 112 and a modulated heating module 113.

[0088] The microring resonator 111 is used to resonate with an optical signal of a specific wavelength and output a monitoring optical signal. Specifically, the microring resonator 111 includes a microring structure and an output structure (corresponding to...). Figure 5 The micro-ring structure (including the ring-shaped and broken-line sections) resonates with a specific wavelength of light signal and outputs the obtained monitoring light signal through the output structure.

[0089] It should be noted that in each wavelength control channel 110, each micro-ring resonator 111 can correspond to the same input waveguide or different input waveguides, which has no substantial impact on this embodiment; when corresponding to the same input waveguide, each micro-ring resonator 111 can be regarded as a cascaded arrangement.

[0090] A photodetector 112, coupled to the output of the micro-ring resonator 111, is used to convert the received monitoring optical signal into an analog current signal output. Specifically, as shown... Figure 5 As shown, the photodetector 112 is a photodiode. Of course, it can also be other photoelectric conversion devices that can convert light signals into current signals, and there is no limitation on this.

[0091] The heating control module 113, coupled to the output of the control module 140, performs thermal tuning on the micro-ring resonator 111 based on the received digital compensation signal. Specifically, the heating control module 113 includes a digital-to-analog converter 1131 and a thermal tuning unit 1132, and further includes a drive unit 1133. Wherein:

[0092] A digital-to-analog converter 1131, coupled to the output of the control module 140, converts the received digital compensation signal into an analog tuning signal for output. A thermal tuning unit 1132, coupled to the output of the digital-to-analog converter 1131, adjusts the effective refractive index and center resonant wavelength of the micro-ring resonator 111 based on the analog tuning signal, thereby achieving thermal tuning of the micro-ring resonator 111. In practical applications, such as... Figure 5 As shown, the thermal tuning unit 1132 is a heating resistor, typically located near the microring resonator 111, to heat a local area of ​​the microring resonator 111. The driving unit 1133, coupled between the digital-to-analog converter 1131 and the thermal tuning unit 1132, drives the thermal tuning unit 1132 by enhancing the driving capability of the analog tuning signal.

[0093] It should be noted that a specific wavelength can also be called a target wavelength, and wavelength locking means locking the center resonant wavelength of the microring resonator 111 to the target wavelength; for different wavelength control channels 110, the corresponding target wavelengths are different.

[0094] Multiplexer 120, coupled to the output of each wavelength modulation channel 110, selects one output from several received analog electrical signals (such as analog current signals) under the control of control module 140. In one embodiment, multiplexer 120 is a multiplexer-to-one switch, wherein each input is correspondingly coupled to the output of each wavelength modulation channel 110, and the output is coupled to the input of analog-to-digital converter 130. The control terminal receives channel switching commands provided by control module 140 to output the analog current signal of the corresponding wavelength modulation channel 110 based on the channel switching commands.

[0095] Conversion module 114, coupled to the output of multiplexer 120, is used to convert the received analog current signal into an analog voltage signal for output. Specifically, as shown... Figure 5 As shown, the conversion module 114 is a transimpedance amplifier that performs current-to-voltage conversion and signal conditioning to output an analog voltage signal with appropriate amplitude. By sharing the conversion module 114, the integration density can be further improved, allowing for the pursuit of ultimate area and power consumption reduction.

[0096] Analog-to-digital converter 130, coupled to the output of conversion module 114, is used to convert received analog electrical signals (such as analog voltage signals) into digital electrical signals for output. Analog-to-digital converter 130 is a voltage-type converter, which, compared to current-type converters, offers advantages such as better compatibility, less impact on the preceding stage, and easier integration.

[0097] The control module 140 is coupled to the output of the analog-to-digital converter 130. Based on the received digital electrical signal, it evaluates the resonance state and thermal drift direction of the micro-ring resonator 111 in the corresponding wavelength control channel 110, generates a corresponding digital compensation signal and outputs it to the corresponding wavelength control channel 110 for thermal tuning. Of course, it also provides channel switching instructions to the multiplexer 120.

[0098] In practical applications, the control module 140 typically has several output terminals, each corresponding to one of the wavelength modulation channels 110, to facilitate the directional distribution of the corresponding digital compensation signals back to the corresponding wavelength modulation channels 110. Additionally, the control module 140 also has a control terminal for providing channel switching signals to the multiplexer 120.

[0099] Example 4

[0100] This embodiment provides a method for thermally modulated wavelength locking of a microring resonator, including the following steps; wherein, the method of this embodiment can be implemented based on the system described in Embodiment 1, Embodiment 2 or Embodiment 3.

[0101] S1, several wavelength control channels 110 resonate with optical signals of their respective specific wavelengths to output several analog electrical signals.

[0102] In the case of the wavelength control channel 110 described in Embodiment 1 or Embodiment 3, this step outputs several analog current signals; in the case of the wavelength control channel 110 described in Embodiment 2, this step outputs several analog voltage signals.

[0103] S2, the multiplexer 120 selects one output from several analog electrical signals in a time-division multiplexing manner; wherein, the time-division multiplexing manner is a time-division multiplexing polling control method, such as the multiplexer 120 sequentially selecting and outputting the analog electrical signal corresponding to the first channel, the analog electrical signal corresponding to the second channel, the analog electrical signal corresponding to the third channel, and so on.

[0104] In addition, for the systems described in Embodiment 1 or Embodiment 3, the analog electrical signal in this step is an analog current signal; for the system described in Embodiment 2, the analog electrical signal in this step is an analog voltage signal.

[0105] S3, the analog-to-digital converter 130 converts the received analog electrical signal into a digital electrical signal.

[0106] In the system described in Embodiment 1, the analog-to-digital converter 130 is a current-type analog-to-digital converter that receives the analog current signal output by the multiplexer 120; in the system described in Embodiment 2, the analog-to-digital converter 130 is a voltage-type analog-to-digital converter that receives the analog voltage signal output by the multiplexer 120; and in the system described in Embodiment 3, the analog-to-digital converter 130 is a voltage-type analog-to-digital converter that receives the analog voltage signal output by the conversion module 114.

[0107] S4, the control module 140 evaluates the resonance state and thermal drift direction of the micro-ring resonator 111 in the corresponding wavelength control channel 110 based on the received digital electrical signal, and generates a corresponding digital compensation signal to be output to the corresponding wavelength control channel 110 for thermal tuning.

[0108] Specifically, the control module 140 stores the wavelength locking algorithm corresponding to each wavelength control channel 110. When a channel is selected, the wavelength locking algorithm corresponding to that channel is called to evaluate and generate the corresponding digital compensation signal. The wavelength locking algorithm can be either a gradient descent algorithm or a PID control algorithm, and there are no restrictions on this.

[0109] S5, jump to S2 to evaluate and output the next wavelength control channel 110, until all wavelength control channels 110 are evaluated and output. It should be noted that this step is triggered when the control module 140 outputs the corresponding digital compensation signal, not when the corresponding wavelength control channel 110 completes thermal tuning.

[0110] Taking the order from first to last as an example, the first time S2~S5 is executed to evaluate and output the first wavelength control channel, the second time S2~S5 is executed to evaluate and output the second wavelength control channel, the third time S2~S5 is executed to evaluate and output the third wavelength control channel, and so on.

[0111] S6, repeat S1~S5 at least once, until wavelength locking of the micro-ring resonators 111 in all wavelength control channels 110 is completed. It should be noted that the number of repetitions is determined by the actual application requirements and is not limited thereto.

[0112] Since the heat conduction and temperature stabilization of a microring resonator are slow physical processes, its thermal response time constant (typically on the order of tens of microseconds or even milliseconds) is much larger than the single conversion time of an analog-to-digital converter (typically on the order of sub-microseconds or even nanoseconds). Therefore, the time-division multiplexing mechanism in this embodiment can ensure that dozens or even hundreds of rounds of sampling and feedback are completed before the local temperature of the microring resonator undergoes substantial physical drift. This design, which uses the high-speed characteristics of the electrical domain to match the slow characteristics of the thermal domain, enables the multi-channel time-division shared architecture to achieve a real-time, stable wavelength locking effect that is completely equivalent to the traditional point-to-point independent control architecture on a macroscopic level. This is equivalent to continuous independent monitoring and adjustment of each stage of the microring resonator, which not only avoids wavelength lock-out or tuning lag, but also gives the system excellent observability and calibrability.

[0113] In practical applications, after wavelength locking of the micro-ring resonators 111 in all wavelength control channels 110 is completed, the status of the micro-ring resonators 111 in each wavelength control channel 110 can be detected. Specifically, the status of the micro-ring resonators 111 in each wavelength control channel 110 is detected in a polling manner. When the micro-ring resonator 111 in the current wavelength control channel 110 loses lock, the polling is interrupted and the micro-ring resonator 111 in the current wavelength control channel 110 is locked and restored. Then, the polling is resumed to detect the status of the micro-ring resonator 111 in the next wavelength control channel 110.

[0114] The main process involves the analog-to-digital converter 130 sampling the optical power data of the micro-ring resonators 111 in each wavelength control channel 110 based on the time-division multiplexing of the multiplexer 120. The control module 140 then determines the degree of deviation between the corresponding optical power data and the corresponding set data, thereby determining whether the corresponding micro-ring resonator 111 has lost lock. Furthermore, for the wavelength control channel 110 that has lost lock, steps S2 to S4 as described above are executed to restore lock.

[0115] In this embodiment, the control module can independently acquire the sampling results of each microring resonator. Therefore, when the system loses lock due to drastic temperature drift or local crosstalk, the control module can quickly locate the abnormal microring resonator based on the changes in the sampling data of each channel, and prioritize locking and restoring the microring resonator. In other words, the method in this embodiment can also quickly locate the source of the fault and support the system to maintain stable operation under complex long-term operating conditions.

[0116] Example 5

[0117] This embodiment provides a terminal, including a microring resonator thermally modulated wavelength locking system 100, wherein the microring resonator thermally modulated wavelength locking system 100 is implemented using the system described in Embodiment 1, Embodiment 2, or Embodiment 3. In practical applications, this terminal can be a transmitting end or a receiving end.

[0118] In summary, the microring resonator thermally modulated wavelength locking system, method, and terminal of this invention, by introducing a multiplexer for hardware-level signal gating, constructs a multi-channel time-division shared analog-to-digital converter architecture. This not only effectively overcomes the wiring congestion and area bottlenecks faced by multi-channel optoelectronic integrated chips, but also significantly reduces the overall system power consumption and local heat island effect caused by the concurrency of multiple analog-to-digital converters, exhibiting extremely high engineering feasibility and system energy efficiency. This invention significantly reduces physical area, lowers total system power consumption, and reduces signal wiring complexity while ensuring wavelength locking accuracy and response speed. Therefore, this invention effectively overcomes the various shortcomings of existing technologies and has high industrial application value.

[0119] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A microring resonator thermally modulated wavelength locking system, characterized in that, It includes several wavelength control channels, a multiplexer, an analog-to-digital converter, and a control module, among which: The wavelength control channel includes a micro-ring resonator, which is used to resonate with optical signals of a specific wavelength to output an analog electrical signal, and also performs thermal tuning based on a digital compensation signal to lock the wavelength. The multiplexer is coupled to the output of each wavelength modulation channel, and under the control of the control module, it selects one output from several received analog electrical signals. The analog-to-digital converter is coupled to the output of the multiplexer and is used to convert the received analog electrical signal into a digital electrical signal for output. The control module is coupled to the output of the analog-to-digital converter. Based on the received digital electrical signal, it evaluates the resonance state and thermal drift direction of the micro-ring resonator in the corresponding wavelength control channel and generates the corresponding digital compensation signal.

2. The microring resonator thermally tuned wavelength locking system according to claim 1, characterized in that, The analog-to-digital converter is a current-mode analog-to-digital converter; The wavelength modulation channel also includes a photodetector and a modulation heating module, wherein: The micro-ring resonator resonates in response to optical signals of a specific wavelength and outputs a monitoring optical signal. The photodetector is coupled to the output of the microring resonator and is used to convert the received monitoring optical signal into an analog current signal output. The heating control module is coupled to the output of the control module and performs thermal tuning on the micro-ring resonator based on the received digital compensation signal.

3. The microring resonator thermally tuned wavelength locking system according to claim 1, characterized in that, The analog-to-digital converter is a voltage-type analog-to-digital converter; The wavelength modulation channel further includes a photodetector, a conversion module, and a modulation heating module, wherein: The micro-ring resonator resonates in response to optical signals of a specific wavelength and outputs a monitoring optical signal. The photodetector is coupled to the output of the microring resonator and is used to convert the received monitoring optical signal into an analog current signal output. The conversion module is coupled to the output terminal of the photodetector and is used to convert the received analog current signal into an analog voltage signal for output. The heating control module is coupled to the output of the control module and performs thermal tuning on the micro-ring resonator based on the received digital compensation signal.

4. The microring resonator thermally tuned wavelength locking system according to claim 1, characterized in that, The analog-to-digital converter is a voltage-type analog-to-digital converter; The wavelength modulation channel also includes a photodetector and a modulation heating module, wherein: The micro-ring resonator resonates in response to optical signals of a specific wavelength and outputs a monitoring optical signal. The photodetector is coupled to the output of the microring resonator and is used to convert the received monitoring optical signal into an analog current signal output. The heating control module is coupled to the output of the control module and performs thermal tuning on the micro-ring resonator based on the received digital compensation signal. The microring resonator thermally modulated wavelength locking system further includes a conversion module coupled between the multiplexer and the analog-to-digital converter, used to convert the received analog current signal into an analog voltage signal for output.

5. The microring resonator thermally tuned wavelength locking system according to claim 3 or 4, characterized in that, The conversion module is a transimpedance amplifier.

6. The microring resonator thermally modulated wavelength locking system according to any one of claims 2 to 4, characterized in that, The heating control module includes a digital-to-analog converter and a thermal tuning unit, wherein: The digital-to-analog converter is coupled to the output of the control module and is used to convert the received digital compensation signal into an analog tuning signal for output. The thermal tuning unit is coupled to the output of the digital-to-analog converter and adjusts the local temperature of the microring resonator based on the analog tuning signal to regulate its effective refractive index and center resonant wavelength.

7. The microring resonator thermally tuned wavelength locking system according to claim 6, characterized in that, The heating control module also includes a drive unit, which is coupled between the digital-to-analog converter and the thermal tuning unit.

8. A terminal, characterized in that, Including the microring resonator thermally modulated wavelength locking system as described in any one of claims 1 to 7.

9. The terminal according to claim 8, characterized in that, The terminal is the sending end.

10. The terminal according to claim 8, characterized in that, The terminal is a receiving end.

11. A method for thermally modulated wavelength locking of a microring resonator, characterized in that, include: S1, several wavelength control channels resonate with optical signals of their respective specific wavelengths to output several analog electrical signals; S2, the multiplexer selects one output from several analog electrical signals in a time-division multiplexing manner; S3, the analog-to-digital converter converts the received analog electrical signal into a digital electrical signal; S4, the control module evaluates the resonance state and thermal drift direction of the micro-ring resonator in the corresponding wavelength control channel based on the received digital electrical signal, and generates the corresponding digital compensation signal to be output to the corresponding wavelength control channel for thermal tuning; S5, jump to S2 to evaluate the next wavelength control channel and output, until all wavelength control channels have been evaluated and output.

12. The microring resonator thermally tuned wavelength locking method according to claim 11, characterized in that, Also includes: S6, repeat S1~S5 at least once until wavelength locking of micro-ring resonators in all wavelength control channels is completed.

13. The microring resonator thermally tuned wavelength locking method according to claim 11 or 12, characterized in that, The time-division multiplexing method is a time-division multiplexing polling control method.

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