Channel equalizer and optical communication system

Abstract

The application relates to the technical field of optical communication, in particular to a channel equalizer and an optical communication system. The signal equalizer comprises: a first dispersion compensation module arranged on a chip main body, the first dispersion compensation module being used for accepting an externally input optical signal and performing dispersion compensation on the central wavelength of the optical signal to form a primary processed optical signal; and a second dispersion compensation module arranged on the chip main body, the second dispersion compensation module being used for performing wave separation processing on the primary processed optical signal of the first dispersion compensation module and performing dispersion compensation on the non-central wavelength of the signal after wave separation. The application integrates the channel equalization function on an optical chip, performs linear calculation processing on the input signal before the optical signal is transmitted into a photoelectric detector, and can realize equalization of the high-speed optical communication signal in the optical domain. Meanwhile, two dispersion compensation modules are integrated on the chip, dispersion compensation is performed on the central wavelength and the non-central wavelength, and the adaptability of the equalizer in different application scenarios is improved.

Description

Technical Field

[0001] This invention relates to the field of optical communication technology, specifically to a channel equalizer and an optical communication system. Background Technology

[0002] The development of artificial intelligence has driven the need for high-capacity information transmission, leading to continuous increases in the transmission rate of optical communication systems, reaching 400G, 800G, and even exceeding 1.6Tbit / s. However, the effects of dispersion, noise, and frequency response of transmitting and receiving devices on optical signals during transmission through optical fibers become increasingly significant with rising signal baud rates, resulting in severe degradation of signal quality at the receiving end. In traditional technologies, channel equalization primarily relies on electronic digital signal processors (DSPs) to compensate for distorted signals through high-speed sampling and complex algorithms. However, with increasing speeds, electronic DSPs are gradually becoming bottlenecks in terms of power consumption, latency, bandwidth, and cost, making it difficult to meet the demands of ultra-high-speed optical communication. The development of photonic integration technology has made it possible to implement signal processing in the optical domain.

[0003] Among related technologies, using optical hardware to directly perform linear multiplication and addition operations offers advantages such as high parallelism, large bandwidth, low latency, and low power consumption, becoming a new approach to overcome the bottleneck of electronic DSPs. However, existing all-optical signal processing chips still face the following prominent problems: First, structurally, existing integrated optical solutions are not specifically designed for channel equalization scenarios. Although some integrated optical computing chips can achieve high computing power with low latency, their incompatibility with application scenarios results in poor dispersion compensation, and they contain a large number of redundant on-chip optical devices. Second, in terms of integration, in WDM systems, signals of different wavelengths have different dispersion values ​​in optical fibers. How to integrate the equalization function of multiple wavelength signals onto a single chip remains a major challenge. Therefore, how to solve the shortcomings of current all-optical signal processing chips in terms of structure and integration has become an urgent problem for practitioners. Summary of the Invention

[0004] Among related technologies, integrated optical solutions suffer from poor dispersion compensation, device redundancy, low communication capacity, and weak noise immunity due to a lack of targeted structural design, insufficient integration, and adaptive control mechanisms. These issues fail to meet the requirements of ultra-high-speed optical communication for low power consumption and high integration.

[0005] In a first aspect, embodiments of this application provide a signal equalizer, which includes: a chip body, a first dispersion compensation module, and a second dispersion compensation module; wherein... The first dispersion compensation module is disposed on the chip body. The first dispersion compensation module is used to receive externally input optical signals and perform dispersion compensation on the center wavelength of the optical signals to form a pre-processed optical signal. The second dispersion compensation module is disposed on the chip body. The second dispersion compensation module is used to perform wavelength division processing on the initial processed optical signal of the first dispersion compensation module, and to perform dispersion compensation on the non-center wavelength of the wavelength division signal.

[0006] In conjunction with the first aspect, in one implementation, the first dispersion compensation module includes: A first optical splitter is disposed on the chip body. The first optical splitter is used to receive optical signals and perform beam splitting on the optical signals. Multiple first delay calculation units are disposed on the chip body. The first delay calculation units are connected to the first beam splitter, and each first delay calculation unit is used to compensate for the center wavelength dispersion of a beam of light. The second optical splitter is disposed on the chip body and is connected to the first delay calculation unit. The second optical splitter is used to perform beam combining processing on multiple optical signals.

[0007] In conjunction with the first aspect, in one embodiment, the first delay calculation unit includes: an adjustable optical interferometer, which is connected to the first beam splitter via a delay line.

[0008] In conjunction with the first aspect, in one embodiment, the adjustable optical interferometer includes a Mach-Zehnder interferometer.

[0009] In conjunction with the first aspect, in one implementation, it further includes: An optical input waveguide is disposed on the chip body and is connected to the first optical splitter. The optical input waveguide is used to receive external optical signals. An optical output waveguide is disposed on the chip body and is connected to the second optical splitter.

[0010] In conjunction with the first aspect, in one embodiment, the second dispersion compensation module includes: A wavelength decomposition and multiplexing unit is disposed on the chip body. The wavelength decomposition and multiplexing unit is connected to the first dispersion compensation module. The wavelength decomposition and multiplexing unit is used for wavelength decomposition processing of the initial processed optical signal. Multiple second delay calculation units are disposed on the chip body. The second delay calculation units are connected to the wave decomposition and multiplexing unit. The second delay calculation units are used to perform dispersion compensation on the received pre-processed optical signal.

[0011] In conjunction with the first aspect, in one embodiment, the wave demultiplexing unit includes an arrayed waveguide grating device disposed on the chip body.

[0012] In conjunction with the first aspect, in one embodiment, the chip body is provided with a control unit, which is used to adjust the compensation adjustment parameters of the first dispersion compensation module and the second dispersion compensation module according to the feedback information of the photodetector.

[0013] It should be noted that in addition to the dispersion effect in the optical fiber, signal transmission also faces the influence of noise and non-ideal transmitting and receiving devices. Therefore, it is necessary to utilize intelligent optimization algorithms to adapt to dispersion equalization tasks of different frequency bands or optical fiber lengths, in order to provide a certain degree of compensation for noise and non-ideal frequency responses of transmitting and receiving devices.

[0014] In conjunction with the first aspect, in one implementation, the feedback information includes the output signal waveform, the reference signal bit error rate, or the signal-to-noise ratio.

[0015] Secondly, embodiments of this application provide an optical communication system, characterized in that it includes: a signal equalizer as described in any of the preceding claims, wherein the signal equalizer is disposed between the optical fiber receiving side and the photodetector.

[0016] The beneficial effects of the technical solutions provided in this application include: This application integrates channel equalization functionality onto an optical chip. Before the optical signal enters the photodetector, the input signal is linearly processed using an on-chip tunable structure. This enables equalization of high-speed optical communication signals in the optical domain, avoiding the energy consumption and delay bottlenecks associated with electrical domain signal processing. Simultaneously, two dispersion compensation modules are integrated on the chip to compensate for dispersion at both the center and non-center wavelengths, improving the equalizer's adaptability to different application scenarios. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the signal equalizer in an embodiment of this application; Figure 2 This is a flowchart illustrating the control algorithm in an embodiment of this application. Detailed Implementation

[0019] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0020] Among the related technologies, integrated optical solutions suffer from poor dispersion compensation, device redundancy, low communication capacity, and weak noise immunity due to a lack of targeted structural design, insufficient integration, and adaptive control mechanisms. They cannot meet the requirements of ultra-high-speed optical communication for low power consumption and high integration.

[0021] It should be noted that an optical communication system includes an optical transmitting module, optical fiber, and an optical receiving module (including a photodetector). When light transmits in this system, waveform distortion occurs, thus requiring a signal equalizer to restore the signal. Existing technology encapsulates an electronic signal processing chip (DSP) within the optical receiving module. In some embodiments of this application, the internal optical path design of the integrated optical computing chip is based on general intelligent computing design, typically employing multi-port low-speed signal input. However, in the signal equalization scenario, a single-port high-speed signal input is used, and these optical computing chips are used to forcibly perform dispersion compensation, resulting in poor performance.

[0022] Firstly, such as Figure 1 As shown, this application provides a signal equalizer, which includes: a chip body, a first dispersion compensation module, and a second dispersion compensation module; wherein, A first dispersion compensation module is disposed on the chip body. The first dispersion compensation module is used to receive externally input optical signals and perform dispersion compensation on the center wavelength of the optical signals to form a pre-processed optical signal. A second dispersion compensation module is disposed on the chip body. The second dispersion compensation module is used to perform wavelength division processing on the pre-processed optical signal of the first dispersion compensation module and perform dispersion compensation on the non-center wavelengths after wavelength division.

[0023] It is worth noting that in the above embodiments of this application, the integrated first dispersion compensation module (i.e., wavelength-insensitive module) and second dispersion compensation module are used to achieve layered compensation for dispersion of the center wavelength and non-center wavelength, which solves the equalization adaptation problem caused by the difference in dispersion characteristics of multiple wavelengths in WDM system, ensures that the equalizer operates compatiblely in different wavelength channel scenarios, and improves the system communication capacity and integration.

[0024] It should be noted that the optical communication system includes an optical transmitting module, optical fiber, and an optical receiving module (including a photodetector). When the optical signal is transmitted in this communication system, waveform distortion occurs, thus requiring a signal equalizer to restore the signal. Some implementations encapsulate an electronic signal processing chip (DSP) within the optical receiving module. However, the signal equalizer scheme of this application uses an optical chip to perform channel equalization. Furthermore, the signal equalizer of this application must be positioned between the optical fiber receiver and the photodetector, eliminating the need for additional photoelectric-to-optical conversion steps.

[0025] In some specific embodiments, the first dispersion compensation module includes: a first beam splitter, a plurality of first delay calculation units, and a second beam splitter; wherein, A first optical splitter is disposed on the chip body and is used to receive optical signals and perform beam splitting on the optical signals; a plurality of first delay calculation units are disposed on the chip body and are connected to the first optical splitter, and each of the first delay calculation units is used to compensate for the center wavelength dispersion of a beam of optical signals; a second optical splitter is disposed on the chip body and is connected to the first delay calculation units and is used to perform beam combining on multiple beams of optical signals.

[0026] It is understood that the above implementation uses a cascaded structure of beam splitting-compensation-combining through a beam splitter and a first delay calculation unit to achieve parallelization and high-precision compensation of center wavelength dispersion, reduce signal processing delay, and improve equalization efficiency.

[0027] Furthermore, the first and second beam splitters can be implemented using an MMI multimode interferometer.

[0028] Preferably, the first delay calculation unit includes an adjustable optical interferometer, which is connected to the first beam splitter via delay lines. Specifically, all optical delay lines and the adjustable optical interferometer on the chip body form an array structure for dispersion compensation.

[0029] It is worth noting that the above embodiments utilize an adjustable optical interferometer to dynamically adjust the phase of the optical signal, thereby achieving real-time adaptive compensation for center wavelength dispersion and enhancing the equalizer's adaptability to changes in fiber optic transmission parameters.

[0030] In some specific embodiments, the adjustable optical interferometer includes a Mach-Zehnder interferometer (i.e., an MZI unit).

[0031] It is worth noting that the MZI unit parameters are adjustable; the dispersion compensation result can be adjusted by changing the MZI unit voltage value. Based on the high-precision phase modulation capability of the Mach-Zehnder interferometer, dispersion compensation is efficiently achieved, ensuring a stable and reliable compensation process and reducing the bit error rate.

[0032] Furthermore, the signal equalizer further includes: an optical input waveguide and an optical output waveguide; wherein, An optical input waveguide is disposed on the chip body and is connected to the first optical splitter coupler. The optical input waveguide is used to receive external optical signals. An optical output waveguide is disposed on the chip body and is connected to the second optical splitter coupler.

[0033] It is worth noting that optical input waveguides and optical output waveguides can simplify the input and output paths of optical signals, avoid photoelectric conversion steps, reduce signal loss and transmission delay, and ensure the continuity of optical domain uniformity.

[0034] Preferably, the first dispersion compensation module includes: an optical delay line integrated on the chip body, multiple MMI beam splitters and input / output waveguides forming a beam splitting and beam combining structure.

[0035] In some specific embodiments, the second dispersion compensation module includes: a wave decomposition and multiplexing unit and a plurality of second delay calculation units; wherein, A wavelength division multiplexing unit is disposed on the chip body and is connected to the first dispersion compensation module. The wavelength division multiplexing unit is used for wavelength division processing of the initial processed optical signal. A plurality of second delay calculation units are disposed on the chip body and are connected to the wavelength division multiplexing unit. The second delay calculation units are used for dispersion compensation of the received initial processed optical signal.

[0036] It is understood that the above embodiments separate multi-wavelength signals through wave demultiplexing units to achieve independent compensation for non-center wavelength dispersion, thereby improving the equalization integration and compatibility of multi-wavelength WDM systems. The on-chip integration of the wave demultiplexing and dispersion compensation modules of this invention not only solves the industry pain point of "multi-wavelength dispersion equalization requiring redundant deployment of multiple chips" in WDM systems, but also achieves high-capacity, low-latency, and low-power all-optical equalization through a single chip.

[0037] In some preferred embodiments, the wave demultiplexing unit includes an arrayed waveguide grating device disposed on the chip body.

[0038] It is worth noting that after the first dispersion compensation, the optical signal is split by the arrayed waveguide grating device and then compensated by each of the small dispersion compensation modules (i.e., the second delay calculation unit). The arrayed waveguide grating device has high-precision wavelength separation capability and optimizes the wavelength demultiplexing efficiency, ensuring the accuracy of non-center wavelength compensation and system stability.

[0039] In some preferred embodiments, the second delay calculation unit includes: an input waveguide, an output waveguide, multiple on-chip optical delay lines, and multiple on-chip optical delay lines forming an array structure.

[0040] In some alternative implementations, the second delay calculation unit is configured the same as the first delay calculation unit.

[0041] It is worth noting that the number of first delay calculation units in the first dispersion compensation module is greater than the number of second delay calculation units in the second dispersion compensation module.

[0042] In some alternative implementations, the first dispersion compensation module includes 16 first delay calculation units. The second dispersion compensation module includes 3 second delay calculation units. The adjustment method for both dispersion compensation modules is the same: adjusting the voltage on the adjustable optical interferometer.

[0043] In some preferred embodiments, the chip body is provided with a control unit, which is used to adjust the compensation adjustment parameters of the first dispersion compensation module and the second dispersion compensation module according to the feedback information of the photodetector.

[0044] Understandably, equalization methods use optoelectronic co-operation systems and electrical hardware to control on-chip optical components.

[0045] Specifically, the equalization method for the control unit includes the following steps: Step S1: Determine the initial values ​​set for the MZI unit based on the fiber dispersion value, length, baud rate, and wavelength of the optical fiber communication system.

[0046] It is understandable that parameters such as fiber dispersion, length, baud rate, and wavelength are known before the design.

[0047] Step S2: Using a control algorithm that includes an adaptive control mechanism, the parameters of the adjustable optical interferometer (i.e., MZI unit) in the first and second delay calculation units are dynamically adjusted by detecting feedback information such as the bit error rate or signal-to-noise ratio of the reference signal.

[0048] Specifically, the feedback information includes the output signal waveform, the reference signal bit error rate, or the signal-to-noise ratio.

[0049] It should be noted that in addition to the dispersion effect in the optical fiber, signal transmission also faces the influence of noise and non-ideal transmitting and receiving devices. Due to the different requirements of different frequency bands, these issues need to be compensated for using adaptive algorithms and corresponding hardware and software in tandem. Therefore, intelligent optimization algorithms are needed to adapt to dispersion equalization tasks of different frequency bands or fiber lengths to provide some compensation for noise and non-ideal frequency responses of transmitting and receiving devices.

[0050] Furthermore, the control algorithm of the adaptive control mechanism in this application is as follows: Figure 2 As shown, the MZI unit parameters mainly refer to the voltage values ​​on each tunable optical interferometer. Changing these parameters will cause different states of the tunable optical interferometer, thus affecting the dispersion compensation results. This application utilizes an adaptive in-situ training algorithm to achieve adaptation to different scenarios through hardware and software collaboration and on-chip tunable structure. At the same time, it reduces the power consumption, latency, and bit error rate of the optical fiber communication system, and replaces or reduces the dependence on electronic digital signal processors, thereby improving the noise immunity of signal transmission.

[0051] The working principle of the signal equalizer in this application includes: the optical signal enters a series of beam splitters through the input waveguide of the first dispersion compensation module. Each beam is multiplied in the complex domain by a delay calculation unit composed of a delay line and an adjustable optical interferometer. Finally, the beams are combined by a series of MMI beam splitters to achieve addition in the complex domain. The combined optical signal is then transmitted to the second dispersion compensation module, where it is further split by a wavelet demultiplexing unit and compensated by each of the second delay calculation units (i.e., small dispersion compensation units).

[0052] It is worth noting that the signal equalizer in this application can equalize signals of multiple wavelengths using only one chip. The channel equalizer of this application is suitable for single-band IMDD optical communication systems with channel spacing >= 200G, and can use multiple signal modulation formats such as OOK and PAM4. The communication rate can reach 1.6Tbits / s, and it achieves lower power consumption and lower bit error rate than electronic digital signal processors.

[0053] In summary, the signal equalizer of this application is based on an integrated optical chip. Before the optical signal is transmitted to the photodetector, the input signal is linearly processed by the on-chip adjustable structure. It can achieve equalization of high-speed optical communication signals in the optical domain, including compensation for dispersion, noise and non-ideal transmit and receive device responses. Furthermore, the wavelength division multiplexing function is also integrated into the same integrated optical chip, enabling the chip to be applied to wavelength division multiplexing (WDM) systems.

[0054] Secondly, this application provides an optical communication system, which includes: a signal equalizer, which is arranged between the optical fiber receiving side and the photodetector.

[0055] It is understood that the signal equalizer of this application is arranged between the optical fiber receiver and the photodetector, thus eliminating the need for additional photoelectric conversion steps.

[0056] The signal equalizer includes: a chip body, a first dispersion compensation module, and a second dispersion compensation module; wherein, A first optical splitter is disposed on the chip body and is used to receive optical signals and perform beam splitting on the optical signals; a plurality of first delay calculation units are disposed on the chip body and are connected to the first optical splitter, and each of the first delay calculation units is used to compensate for the center wavelength dispersion of a beam of optical signals; a second optical splitter is disposed on the chip body and is connected to the first delay calculation units and is used to perform beam combining on multiple beams of optical signals.

[0057] It is understood that the above implementation uses a cascaded structure of beam splitting-compensation-combining through a beam splitter and a first delay calculation unit to achieve parallelization and high-precision compensation of center wavelength dispersion, reduce signal processing delay, and improve equalization efficiency.

[0058] Furthermore, the first and second beam splitters can be implemented using an MMI multimode interferometer.

[0059] Preferably, the first delay calculation unit includes an adjustable optical interferometer, which is connected to the first beam splitter via delay lines. Specifically, all optical delay lines and the adjustable optical interferometer on the chip body form an array structure for dispersion compensation.

[0060] It is worth noting that the above embodiments utilize an adjustable optical interferometer to dynamically adjust the phase of the optical signal, thereby achieving real-time adaptive compensation for center wavelength dispersion and enhancing the equalizer's adaptability to changes in fiber optic transmission parameters.

[0061] In some specific embodiments, the adjustable optical interferometer includes a Mach-Zehnder interferometer (i.e., an MZI unit).

[0062] It is worth noting that the MZI unit parameters are adjustable; the dispersion compensation result can be adjusted by changing the MZI unit voltage value. Based on the high-precision phase modulation capability of the Mach-Zehnder interferometer, dispersion compensation is efficiently achieved, ensuring a stable and reliable compensation process and reducing the bit error rate.

[0063] Furthermore, the signal equalizer further includes: an optical input waveguide and an optical output waveguide; wherein, An optical input waveguide is disposed on the chip body and is connected to the first optical splitter coupler. The optical input waveguide is used to receive external optical signals. An optical output waveguide is disposed on the chip body and is connected to the second optical splitter coupler.

[0064] It is worth noting that optical input waveguides and optical output waveguides can simplify the input and output paths of optical signals, avoid photoelectric conversion steps, reduce signal loss and transmission delay, and ensure the continuity of optical domain uniformity.

[0065] Preferably, the first dispersion compensation module includes: an optical delay line integrated on the chip body, multiple MMI beam splitters and input / output waveguides forming a beam splitting and beam combining structure.

[0066] In some specific embodiments, the second dispersion compensation module includes: a wave decomposition and multiplexing unit and a plurality of second delay calculation units; wherein, A wavelength division multiplexing unit is disposed on the chip body and is connected to the first dispersion compensation module. The wavelength division multiplexing unit is used for wavelength division processing of the initial processed optical signal. A plurality of second delay calculation units are disposed on the chip body and are connected to the wavelength division multiplexing unit. The second delay calculation units are used for dispersion compensation of the received initial processed optical signal.

[0067] It is understood that the above embodiments separate multi-wavelength signals through wave demultiplexing units to achieve independent compensation for non-center wavelength dispersion, thereby improving the equalization integration and compatibility of multi-wavelength WDM systems. The on-chip integration of the wave demultiplexing and dispersion compensation modules of this invention not only solves the industry pain point of "multi-wavelength dispersion equalization requiring redundant deployment of multiple chips" in WDM systems, but also achieves high-capacity, low-latency, and low-power all-optical equalization through a single chip.

[0068] In some preferred embodiments, the wave demultiplexing unit includes an arrayed waveguide grating device disposed on the chip body.

[0069] It is worth noting that after the first dispersion compensation, the optical signal is split by the arrayed waveguide grating device and then compensated by each of the small dispersion compensation modules (i.e., the second delay calculation unit). The arrayed waveguide grating device has high-precision wavelength separation capability and optimizes the wavelength demultiplexing efficiency, ensuring the accuracy of non-center wavelength compensation and system stability.

[0070] In some preferred embodiments, the second delay calculation unit includes: an input waveguide, an output waveguide, multiple on-chip optical delay lines, and multiple on-chip optical delay lines forming an array structure.

[0071] In some alternative implementations, the second delay calculation unit is configured the same as the first delay calculation unit.

[0072] It is worth noting that the number of first delay calculation units in the first dispersion compensation module is greater than the number of second delay calculation units in the second dispersion compensation module.

[0073] In some alternative implementations, the first dispersion compensation module includes 16 first delay calculation units. The second dispersion compensation module includes 3 second delay calculation units. The adjustment method for both dispersion compensation modules is the same: adjusting the voltage on the adjustable optical interferometer.

[0074] In some preferred embodiments, the chip body is provided with a control unit, which is used to adjust the compensation adjustment parameters of the first dispersion compensation module and the second dispersion compensation module according to the feedback information of the photodetector.

[0075] Understandably, equalization methods use optoelectronic co-operation systems and electrical hardware to control on-chip optical components.

[0076] Specifically, the equalization method for the control unit includes the following steps: Step S1: Determine the initial values ​​set for the MZI unit based on the fiber dispersion value, length, baud rate, and wavelength of the optical fiber communication system.

[0077] It is understandable that parameters such as fiber dispersion, length, baud rate, and wavelength are known before the design.

[0078] Step S2: Using a control algorithm that includes an adaptive control mechanism, the parameters of the adjustable optical interferometer (i.e., MZI unit) in the first and second delay calculation units are dynamically adjusted by detecting feedback information such as the bit error rate or signal-to-noise ratio of the reference signal.

[0079] Specifically, the feedback information includes the output signal waveform, the reference signal bit error rate, or the signal-to-noise ratio.

[0080] It should be noted that in addition to the dispersion effect in the optical fiber, signal transmission also faces the influence of noise and non-ideal transmitting and receiving devices. Due to the different requirements of different frequency bands, these issues need to be compensated for using adaptive algorithms and corresponding hardware and software in tandem. Therefore, intelligent optimization algorithms are needed to adapt to dispersion equalization tasks of different frequency bands or fiber lengths to provide some compensation for noise and non-ideal frequency responses of transmitting and receiving devices.

[0081] Furthermore, the control algorithm of the adaptive control mechanism in this application is as follows: Figure 2As shown, the MZI unit parameters mainly refer to the voltage values ​​on each tunable optical interferometer. Changing these parameters will cause different states of the tunable optical interferometer, thus affecting the dispersion compensation results. This application utilizes an adaptive in-situ training algorithm to achieve adaptation to different scenarios through hardware and software collaboration and on-chip tunable structure. At the same time, it reduces the power consumption, latency, and bit error rate of the optical fiber communication system, and replaces or reduces the dependence on electronic digital signal processors, thereby improving the noise immunity of signal transmission.

[0082] The working principle of the signal equalizer in this application includes: the optical signal enters a series of beam splitters through the input waveguide of the first dispersion compensation module. Each beam is multiplied in the complex domain by a delay calculation unit composed of a delay line and an adjustable optical interferometer. Finally, the beams are combined by a series of MMI beam splitters to achieve addition in the complex domain. The combined optical signal is then transmitted to the second dispersion compensation module, where it is further split by a wavelet demultiplexing unit and compensated by each of the second delay calculation units (i.e., small dispersion compensation units).

[0083] It is worth noting that the signal equalizer in this application can equalize signals of multiple wavelengths using only one chip. The channel equalizer of this application is suitable for single-band IMDD optical communication systems with channel spacing >= 200G, and can use multiple signal modulation formats such as OOK and PAM4. The communication rate can reach 1.6Tbits / s, and it achieves lower power consumption and lower bit error rate than electronic digital signal processors.

[0084] In summary, the signal equalizer of this application is based on an integrated optical chip. Before the optical signal is input to the photodetector, it performs linear calculations on the input signal using an on-chip tunable structure. This enables equalization of high-speed optical communication signals in the optical domain, including compensation for dispersion, noise, and non-ideal transmission and reception device responses. Furthermore, wavelength division multiplexing (WDM) functionality is also integrated into the same integrated optical chip, allowing the chip to be applied to WDM systems. Simultaneously, it utilizes intelligent optimization algorithms to dynamically adapt to dispersion equalization tasks at different wavelengths or fiber lengths, and effectively compensates for noise and non-ideal frequency responses of the transmitting and receiving devices, significantly enhancing the system's versatility and environmental adaptability.

[0085] It should be noted that the sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0086] The terms "comprising" and "having," and any variations thereof, in the specification, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such process, method, product, or apparatus. The terms "first," "second," and "third," etc., are used to distinguish different objects, etc., and do not indicate a sequence, nor do they limit "first," "second," and "third" to different types.

[0087] In the description of the embodiments of this application, terms such as "exemplary," "for example," or "for instance" are used to indicate examples, illustrations, or explanations. Any embodiment or design described as "exemplary," "for example," or "for instance" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of terms such as "exemplary," "for example," or "for instance" is intended to present the relevant concepts in a concrete manner.

[0088] In the description of the embodiments of this application, unless otherwise stated, " / " means "or". For example, A / B can mean A or B. The "and / or" in the text is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in the description of the embodiments of this application, "multiple" means two or more.

[0089] In some processes described in the embodiments of this application, multiple operations or steps are included in a specific order. However, it should be understood that these operations or steps may not be executed in the order they appear in the embodiments of this application, or they may be executed in parallel. The sequence number of the operation is only used to distinguish different operations, and the sequence number itself does not represent any execution order. In addition, these processes may include more or fewer operations, and these operations or steps may be executed sequentially or in parallel, and these operations or steps may be combined.

[0090] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above, and includes several instructions to cause a terminal device to execute the methods described in the various embodiments of this application.

[0091] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A signal equalizer, characterized in that, include: Chip body; The first dispersion compensation module is disposed on the chip body. The first dispersion compensation module is used to receive externally input optical signals and perform dispersion compensation on the center wavelength of the optical signals to form a pre-processed optical signal. The second dispersion compensation module is disposed on the chip body. The second dispersion compensation module is used to perform wavelength division processing on the initial processed optical signal of the first dispersion compensation module, and to perform dispersion compensation on the non-center wavelength of the wavelength division signal. The first dispersion compensation module includes: a first beam splitter, disposed on the chip body, the first beam splitter being used to receive optical signals and perform beam splitting on the optical signals; a plurality of first delay calculation units, disposed on the chip body, the first delay calculation units being connected to the first beam splitter, and each of the first delay calculation units being used to compensate for the center wavelength dispersion of a beam of optical signals; and a second beam splitter, disposed on the chip body, the second beam splitter being connected to the first delay calculation units, the second beam splitter being used to perform beam combining on multiple beams of optical signals. The second dispersion compensation module includes: a wavelength demultiplexing unit disposed on the chip body, the wavelength demultiplexing unit being connected to the first dispersion compensation module, the wavelength demultiplexing unit being used for wavelength demultiplexing processing of the initial processed optical signal; and a plurality of second delay calculation units disposed on the chip body, the second delay calculation units being connected to the wavelength demultiplexing unit, the second delay calculation units being used for dispersion compensation of the received initial processed optical signal; The number of the first delay calculation units is greater than the number of the second delay calculation units.

2. The signal equalizer as described in claim 1, characterized in that, The first delay calculation unit includes an adjustable optical interferometer, which is connected to the first beam splitter via a delay line.

3. The signal equalizer as described in claim 2, characterized in that, The adjustable optical interferometer includes a Mach-Zehnder interferometer.

4. The signal equalizer as described in claim 1, characterized in that, Also includes: An optical input waveguide is disposed on the chip body and is connected to the first optical splitter. The optical input waveguide is used to receive external optical signals. An optical output waveguide is disposed on the chip body and is connected to the second optical splitter.

5. The signal equalizer as described in claim 1, characterized in that, The wave demultiplexing unit includes an arrayed waveguide grating device disposed on the chip body.

6. The signal equalizer as described in claim 1, characterized in that: The chip body is equipped with a control unit, which is used to adjust the compensation adjustment parameters of the first dispersion compensation module and the second dispersion compensation module according to the feedback information of the photodetector.

7. The signal equalizer as described in claim 6, characterized in that: The feedback information includes the output signal waveform, the reference signal bit error rate, or the signal-to-noise ratio.

8. An optical communication system, characterized in that, include: The signal equalizer as described in any one of claims 1-7, wherein the signal equalizer is disposed between the optical fiber receiving side and the photodetector.

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