Phase bias voltage optimization method and device of passive optical network modulator

Abstract

The invention relates to the field of optical access networks, and provides a phase bias optimization method and device for a passive optical network modulator, and the method comprises the steps: obtaining a single side band signal; driving a passive optical network modulator by using the single sideband signal, and modulating an optical carrier of the passive optical network modulator to obtain a modulated optical signal; acquiring a spectrum of the modulated optical signal; and adjusting the phase bias value of the passive optical network modulator according to the power difference between the primary sideband and the secondary sideband in the spectrum until the spectrum of the modulated optical signal obtained after adjustment is determined to present the single sideband characteristic. According to the invention, the phase bias of the passive optical network modulator is adjusted in real time by monitoring the power difference of the main and secondary sidebands in the spectrum of the modulated optical signal, so that the optimization efficiency and accuracy of the phase bias are improved.

Description

Technical Field

[0001] This invention relates to the field of optical access network technology, and in particular to a method and apparatus for optimizing the phase bias voltage of a passive optical network modulator. Background Technology

[0002] Passive Optical Networks (PONs) are point-to-multipoint optical transmission systems. With the completion of the 50G PON standard, research on PONs exceeding 100G is underway. To improve transmission rate and power budget, standards organizations recommend using coherent modulation schemes, where in-phase and quadrature (IQ) modulators are used to generate quadrature modulation signals. Phase bias voltage control ensures a 90-degree phase shift between the two arms of the signal, thus outputting an ideal signal. However, when the phase bias voltage deviates from the optimal value, it can cause distortion of the signal constellation points, affecting performance.

[0003] Against this backdrop, existing phase bias setting schemes employ a "scanning" phase search method, which involves trying different phase bias values ​​one by one. At each phase bias value, a signal is transmitted, demodulated at the receiver, and digital signal processed to generate and analyze a constellation diagram. The adjustment direction is determined based on the quality of the constellation diagram until the optimal phase bias value is found. However, existing solutions require completing the entire signal link processing during each adjustment, including transmission, reception, and complex calculations. This adjustment method is time-consuming, complex, and cannot be performed in real time, resulting in low efficiency and accuracy in phase bias optimization. Summary of the Invention

[0004] This invention provides a phase bias optimization method, apparatus, electronic device, storage medium, and computer program product for a passive optical network modulator, which solves the defects of existing technologies such as long adjustment time, high complexity, and inability to operate in real time, thereby improving the efficiency and accuracy of phase bias optimization.

[0005] This invention provides a method for optimizing the phase bias voltage of a passive optical network modulator, comprising the following steps: Acquire single-sideband signal; The single-sideband signal is used to drive the passive optical network modulator, and the optical carrier of the passive optical network modulator is modulated to obtain a modulated optical signal; Obtain the spectrum of the modulated optical signal; Based on the power difference between the main sideband and the secondary sideband in the spectrum, the phase bias value of the passive optical network modulator is adjusted until it is determined that the spectrum of the modulated optical signal obtained after adjustment exhibits single-sideband characteristics.

[0006] According to the phase bias optimization method of a passive optical network modulator provided by the present invention, the step of determining that the spectrum of the modulated optical signal obtained after adjustment exhibits single-sideband characteristics includes: It is determined that the power difference between the main sideband and the secondary sideband in the spectrum of the modulated optical signal obtained after adjustment is greater than a preset threshold.

[0007] According to the present invention, a method for optimizing the phase bias of a passive optical network modulator includes adjusting the phase bias value of the passive optical network modulator based on the power difference between the main sideband and the secondary sideband in the spectrum, comprising: The phase bias value of the passive optical network modulator is adjusted based on the power difference between the lowest power of the main sideband and the highest power of the secondary sideband.

[0008] According to the present invention, a phase bias optimization method for a passive optical network modulator is provided, wherein obtaining the single-sideband signal includes: Generate a bilateral charged signal; the bilateral charged signal is a function related to a time variable; The single-sided charged signal is obtained by convolving the bilateral charged signal with the unit impulse response; wherein the unit impulse response is the reciprocal of the product of the time variable and pi.

[0009] According to the present invention, a phase bias optimization method for a passive optical network modulator is provided, wherein the bilaterally charged signal is an electrical signal with an arbitrary baud rate.

[0010] According to the phase bias optimization method for a passive optical network modulator provided by the present invention, the step of obtaining the spectrum of the modulated optical signal includes: A preset proportion of optical signal is separated from the modulated optical signal by a preset beam splitter; The preset ratio of light signal is input into a spectrometer for real-time spectral monitoring to obtain the spectrum.

[0011] According to the phase bias optimization method for a passive optical network modulator provided by the present invention, the execution of the real-time spectral monitoring is triggered by at least one of the following methods: Execute periodically at preset time intervals; or An event is triggered when the performance parameters of the passive optical network are detected to deteriorate beyond a preset threshold; the performance parameters include at least one of bit error rate, error vector amplitude, or signal-to-noise ratio.

[0012] The present invention also provides a phase bias optimization device for a passive optical network modulator, comprising the following modules: The first acquisition module is used to acquire single-sideband signals; The first processing module is used to drive the passive optical network modulator with the single sideband signal and modulate the optical carrier of the passive optical network modulator to obtain a modulated optical signal. The second acquisition module is used to acquire the spectrum of the modulated optical signal; The second processing module is used to adjust the phase bias value of the passive optical network modulator according to the power difference between the main sideband and the secondary sideband in the spectrum, until it is determined that the spectrum of the modulated optical signal obtained after adjustment exhibits single-sideband characteristics.

[0013] The present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the phase bias optimization method of any of the passive optical network modulators described above.

[0014] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the phase bias optimization method for a passive optical network modulator as described above.

[0015] The present invention also provides a computer program product, including a computer program that, when executed by a processor, implements the phase bias optimization method for any of the passive optical network modulators described above.

[0016] In summary, one or more technical solutions provided in the embodiments of this application have at least the following technical effects or advantages: By acquiring the single-sideband signal, the necessary prerequisite for subsequent spectral-based judgment is provided, allowing the accuracy of the modulator's phase bias to be directly reflected through an asymmetric spectral morphology. Based on this, by using the single-sideband signal to drive a passive optical network modulator (PON) and modulating its optical carrier to obtain a modulated optical signal, the invisible phase bias error within the modulator is transformed into an externally visible and measurable change in the spectral morphology of the modulated optical signal. Next, by acquiring the spectrum of the modulated optical signal, real-time spectral observation replaces the traditional process of signal reception and complex digital signal processing, greatly simplifying the monitoring process and reducing operational complexity. Finally, by adjusting the phase bias value of the PON modulator based on the power difference between the main and secondary sidebands in the spectrum until the adjusted modulated optical signal exhibits single-sideband characteristics, the previously experience-based and inefficient search method is transformed into a control process with clear quantitative indicators. This enables rapid and accurate setting of the phase bias value, significantly improving work efficiency and adjustment accuracy. Attached Figure Description

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

[0018] Figure 1 This is a schematic diagram of the IQ modulator provided by the present invention.

[0019] Figure 2 This is one of the schematic diagrams illustrating the effect of VP on the IQ modulation signal provided by the present invention.

[0020] Figure 3 This is the second schematic diagram of the effect of VP on the IQ modulation signal provided by the present invention.

[0021] Figure 4 This is a schematic flowchart of the phase bias optimization method for passive optical network modulators provided by the present invention.

[0022] Figure 5 This is a schematic diagram of a double-sided charged signal provided by the present invention.

[0023] Figure 6 This is a schematic diagram of a single-sided charged signal provided by the present invention.

[0024] Figure 7 This is a schematic diagram of the phase bias optimization device for the passive optical network modulator provided by the present invention.

[0025] Figure 8 This is a schematic diagram of the structure of the electronic device provided by the present invention. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0027] It should be noted that in the description of this invention, the terms "comprising," "including," or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element. The terms "upper," "lower," etc., indicating orientation or positional relationships according to the accompanying drawings, are only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0028] The terms "first," "second," etc., used in this invention are used to distinguish similar objects, not to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the invention can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class, without limiting the number of objects; for example, a first object can be one or more. Furthermore, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0029] The following is combined with Figures 1 to 8 This invention describes the phase bias optimization method, apparatus, electronic device, storage medium, and computer program product for passive optical network modulators.

[0030] Passive Optical Networks (PONs) are point-to-multipoint (P2MP) optical transmission systems. With the 50G PON standard largely complete, research on PONs exceeding 100G is underway. For PONs exceeding 100G, multiple international standards organizations, including the ITU-T, recommend using coherent modulation schemes to achieve high power budget reception while increasing transmission rates. IQ modulators are commonly used optoelectronic modulation devices for generating coherent modulation signals, and their structure is as follows... Figure 1 As shown, Figure 1This is a schematic diagram of the IQ modulator provided by the present invention. In order to make the two arms of the output signal of the modulator satisfy the orthogonality, it is generally necessary to control the phase bias voltage VP to make the XQ signal generate a 90-degree phase rotation, and finally output the quadrature modulation signal XI+jXQ.

[0031] For quadrature modulation signals, the signal with superior performance is generated when the voltage value set by VP ensures that XI and XQ have a 90-degree phase difference. When the voltage value set by VP deviates from the optimal value, the modulated signal will not satisfy the 90-degree orthogonality requirement. When VP is set appropriately, the constellation points are as follows: Figure 2 As shown, Figure 2 This is one of the schematic diagrams illustrating the effect of VP on the IQ modulation signal provided by this invention; when VP is set improperly, the constellation points will be distorted and tilted, such as... Figure 3 As shown, Figure 3 This is the second schematic diagram of the effect of VP on the IQ modulation signal provided by the present invention.

[0032] In existing technical solutions, to obtain a reasonable VP voltage value, a phase search method is generally used to "scan" and set the VP voltage value to find the optimal VP voltage value. This solution requires demodulation processing of multiple signals for each VP voltage value setting, increasing the workload and reducing the efficiency of voltage setting.

[0033] As mentioned before, the existing "scanning" method for finding the optimal operating point requires receiving and processing the transmitted signal at each voltage value, observing the signal constellation diagram after digital signal processing, and determining the direction for further adjustments. This operation greatly reduces the efficiency of the VP setup process.

[0034] To improve the ease of setting the VP voltage, this invention provides a modulator phase bias setting method for over 100G PONs. This method aims to simplify the phase bias setting process and improve adjustment efficiency. To achieve this goal, a direct correlation needs to be established between the modulator phase bias state and its output optical signal spectrum, as detailed below.

[0035] Reference Figure 4 , Figure 4 This is a flowchart illustrating the phase bias optimization method for passive optical network modulators provided by the present invention, as shown below. Figure 4 As shown, steps 101 to 104 are included: Step 101: Obtain the single-sideband signal.

[0036] The first step of this method is to acquire the single-sideband signal. Because the spectral characteristics of the output optical signal after modulation can directly and clearly reflect the accuracy of the modulator's phase bias, this replaces the complex demodulation and constellation diagram analysis process in traditional schemes.

[0037] In one specific embodiment, a single-sideband signal refers to a signal whose signal energy is primarily concentrated within a single frequency band on one side of the carrier frequency. This asymmetric spectral structure is key to this technical solution. This characteristic ensures that when subsequently modulated into an optical signal, any distortion introduced by phase bias inaccuracies will appear as observable sidebands on the other side of the spectrum. In practice, the transmitting device of a passive optical network can be configured to acquire the single-sideband signal. This signal will then be used as the electrical signal to drive the modulator.

[0038] Step 101 yields a specific test signal for subsequent monitoring. The technical advantage of this step lies in providing the necessary prerequisite for establishing a simplified, spectral observation-based phase bias adjustment scheme. The obtained single-sideband signal allows direct visualization of the phase bias setting state, thus laying the foundation for rapid and efficient subsequent phase bias adjustment and significantly reducing the complexity of the entire setup process.

[0039] After acquiring the single-sideband signal, it needs to be converted into a monitorable optical signal. The spectral characteristics of this optical signal must be able to reflect the operating state of the modulator. Therefore, the present invention then proceeds to step 102: using the single-sideband signal to drive the passive optical network modulator, and modulating the optical carrier of the passive optical network modulator to obtain a modulated optical signal.

[0040] In this embodiment, the passive optical network modulator typically refers to an IQ modulator used to generate coherent modulation signals. This modulator contains a core component for adjusting the phase relationship between the two signals, and its phase bias is the target to be optimized in this method. The optical carrier is a continuous wave of light generated by a laser source, which serves as the carrier of information and is fed into the modulator.

[0041] In a specific implementation of step 102, the single-sideband signal obtained in step 101 is input to the electrical signal port of the passive optical network modulator (PON) to drive the PON modulator to operate. The PON modulator then modulates the input optical carrier according to the amplitude and phase of the input single-sideband signal. The output of the PON modulator then receives the modulated optical signal.

[0042] Step 102 successfully reproduces the characteristics of a specific electrical signal in the optical domain. More importantly, it establishes a physical relationship between the phase bias error of the passive optical network modulator and the spectral morphology of the output modulated optical signal. If the phase bias is not set properly, distortion will occur during modulation, which will be directly reflected in the spectrum of the modulated optical signal, specifically by the generation of an unwanted sideband. In this way, a problem of setting an internal, invisible electrical parameter is transformed into an external, directly measurable optical phenomenon.

[0043] In order to make the key information contained in the modulated optical signal for determining the phase bias state available for analysis and adjustment, this optical characteristic needs to be made explicit. Therefore, the present invention then proceeds to step 103: acquiring the spectrum of the modulated optical signal.

[0044] In this embodiment, the spectrum refers to the power distribution of the modulated optical signal in the optical frequency domain. This distribution can clearly show the main sideband where the signal energy is mainly concentrated, as well as the secondary sidebands that may be generated due to imperfect modulation.

[0045] The specific implementation of step 103 involves guiding the modulated optical signal generated in step 102 to a corresponding optical analysis device. The optical analysis device can resolve the corresponding power of the optical signal at different frequency components, thereby obtaining its complete spectrum.

[0046] Step 103 transforms the invisible phase bias setting within the modulator into a directly observable physical graph or data. The resulting spectrum provides a direct basis for subsequent judgment and adjustment. It transforms a signal quality issue that previously required complex demodulation for evaluation into a quantifiable spectral characteristic problem, thus greatly simplifying the evaluation process.

[0047] After obtaining the spectrum of the modulated optical signal, the modulator needs to be adjusted based on the spectrum to achieve optimal operating conditions. Therefore, this method ultimately performs an adjustment and judgment step, namely, step 104: adjusting the phase bias value of the passive optical network modulator based on the power difference between the main sideband and the secondary sideband in the spectrum until it is determined that the spectrum of the modulated optical signal obtained after adjustment exhibits single-sideband characteristics.

[0048] In this embodiment, the power difference between the main sideband and the secondary sideband in the spectrum is a core indicator used to quantify modulation quality. The main sideband carries the effective signal information, while the secondary sideband is an unwanted signal component generated due to phase bias inaccuracies. Therefore, the greater the power difference between the two, the better the signal quality.

[0049] The specific method for determining whether the spectrum of the adjusted modulated optical signal exhibits single-sideband characteristics lies in determining whether the power difference between the main sideband and the secondary sideband in the spectrum of the adjusted modulated optical signal is greater than a preset threshold. The preset threshold is a pre-set judgment standard, such as 15 dB. When the power difference reaches or exceeds this value, the spectrum can be considered to exhibit single-sideband characteristics, thus determining that the phase bias voltage of the modulator has been adjusted properly.

[0050] The specific implementation of step 104 is to observe the spectrum output by the spectrometer in real time. When VP is set reasonably, the spectrum of the modulated optical signal output by the modulator exhibits single-sideband characteristics, and at this time, the VP value is a relatively optimal VP value; as the difference between the VP value and the optimal VP value gradually increases, the spectrum of the modulated optical signal will no longer guarantee single-sideband characteristics.

[0051] Since the power difference between the main and secondary sidebands reflects whether the spectrum exhibits single-sideband characteristics, if this power difference is less than a preset threshold, the phase bias applied to the passive optical network modulator is fine-tuned. This adjustment changes the spectrum of the output optical signal, and the change in power difference can be immediately observed by the adjuster. This adjustment process continues until the observed power difference exceeds the preset threshold.

[0052] Step 104 achieves an efficient and quantifiable phase bias optimization process. It transforms an abstract "optimal state" problem into a task with a clear objective (preset threshold) and a clear judgment criterion (power difference). In this way, the phase bias value of the passive optical network modulator can be set quickly and accurately, ensuring the high quality of the modulator output signal and greatly improving the convenience and accuracy of the entire setting process.

[0053] In one specific embodiment, the method for acquiring the single-sideband signal is described in detail. Specifically, step 101 includes the following steps: Generate a two-sided charged signal; the two-sided charged signal is a function dependent on the time variable; A single-sided charged signal is obtained by convolving the two-sided charged signal with the unit impulse response; where the unit impulse response is the reciprocal of the product of the time variable and pi.

[0054] Specifically, the generation of the double-sided charged signal is completed in the digital signal processing unit of the passive optical network transmitter (such as the Optical Line Terminal, OLT). First, a digital signal generator produces a pseudo-random binary sequence. This sequence is then mapped to specific complex modulation symbols, such as quadrature phase shift keying (QPSK) symbols. The digital baseband signal composed of these symbols is the double-sided charged signal. The electrical spectrum of this signal is symmetrically distributed around zero frequency. An important technical feature is that the double-sided charged signal generated by this method is an electrical signal with arbitrary baud rate, which ensures that this method can be applied to PON systems of different rate levels in the future.

[0055] Next, the bilateral charged signal is transformed, that is, the bilateral charged signal is transformed. With unit impulse response Perform convolution operation to obtain a single-sided charged signal. The unit impulse response is a time variable. With Pi The reciprocal of the product. The specific formula for transforming a two-sided charged signal into a one-sided charged signal is as follows: in, This is a convolution operation; This is the integration variable, used to iterate through all time points on the time axis.

[0056] For specific examples of bilaterally charged signals and single-sided charged signals, please refer to [link / reference]. Figure 5 and Figure 6 , Figure 5 This is a schematic diagram of a double-sided charged signal provided by the present invention. Figure 6 This is a schematic diagram of a single-sided charged signal provided by the present invention.

[0057] Through the above steps, this invention provides a method for generating high-precision single-sideband (SSB) signals entirely in the digital domain. Starting from an easily generated standard double-sideband (SSB) signal, this method transforms it to obtain a high-quality test signal. Since the entire process is performed by digital signal processing, it boasts extremely high accuracy and repeatability, ensuring that the electrical signal input to the modulator itself possesses ideal SSB characteristics. This provides a reliable benchmark for subsequent steps.

[0058] In one specific embodiment, the method for acquiring the spectrum of the modulated optical signal is described in detail. Specifically, step 103 includes the following steps: A preset ratio of optical signal is separated from the modulated optical signal by a preset beam splitter; A preset ratio of light signal is input into a spectrometer for real-time spectral monitoring to obtain the spectrum.

[0059] Specifically, a preset proportion of optical signal is first separated from the modulated optical signal using a preset optical splitter. The preset optical splitter is a low-insertion-loss fused biconical fiber splitter. The preset proportion is preferably 1%. In a specific implementation, the preset optical splitter is connected to the output port of the passive optical network modulator. To compensate for the slight insertion loss introduced by this device into the main link, the output power of the transmitting optical module is pre-calibrated. For example, if the insertion loss of the splitter on 99% of the main fiber is known to be 0.1 dB, the initial transmit power of the optical module will be increased by 0.1 dB accordingly to ensure that the power budget reaching the backbone fiber network is not affected.

[0060] After separating the monitoring signal, the next step is to input a preset proportion of optical signal into a spectrometer for real-time spectral monitoring to obtain the spectrum. The spectrometer is a high dynamic range testing instrument. The optical signal output from the 1% monitoring port of the preset spectrometer in the previous step is connected to the input port of the spectrometer via a fiber optic patch cable. To achieve effective real-time spectral monitoring, the sampling parameters of the spectrometer are specifically set. Its center wavelength is set to the nominal wavelength of the optical carrier. The scanning range is set to a narrow interval, such as 5 nm, to focus on the signal itself and its adjacent frequency bands. The resolution bandwidth (RBW) is set to 0.1 nm or a finer level to ensure that the main sidebands and any possible weak secondary sidebands can be clearly distinguished. Simultaneously, the instrument's scanning time is set to less than 1 second to ensure that the operator can observe instantaneous spectral changes when adjusting the phase bias voltage, thereby obtaining the spectrum.

[0061] Furthermore, in a preferred embodiment, the timing of real-time spectral monitoring is described in detail. The purpose is to improve the automation and intelligence of network operation and maintenance, ensure that the phase bias is always maintained in an optimal state, and avoid unnecessary resource consumption. Specifically, real-time spectral monitoring is triggered by at least one of the following methods: periodically at preset time intervals; or triggered by an event when the performance parameters of the passive optical network are detected to deteriorate beyond a preset threshold; the performance parameters include at least one of bit error rate, error vector amplitude, or signal-to-noise ratio.

[0062] In this embodiment, performance parameters are key indicators used to characterize the quality of passive optical network communication links, specifically including at least one of bit error rate, error vector amplitude, or signal-to-noise ratio. The preset time interval is a time parameter configurable by the network administrator, such as 24 hours or one week. The preset threshold is a performance alarm threshold pre-set for the aforementioned performance parameters, for example, a bit error rate higher than 10⁻⁴.

[0063] The specific implementation of this method is as follows: In the first approach, a timer is embedded in the management system of the passive optical network transmitter. This timer automatically and periodically initiates the complete phase bias detection and adjustment process according to a preset time interval. In the second approach, the transmitter continuously monitors the uplink performance parameters during normal data communication. When the monitoring system detects that the current value of a certain performance parameter has deteriorated and exceeds its corresponding preset threshold, this event triggers the execution of the complete phase bias detection and adjustment process as an automated fault repair attempt.

[0064] Through the above steps, a high-precision online monitoring system with minimal impact on the main link was constructed. Power compensation avoided negative impacts on the system power budget. By precisely setting the spectrometer parameters, this scheme ensured the reliability and real-time nature of the monitoring results, and clearly quantified the power relationship between the main and secondary sidebands. This provides a foundation for subsequent rapid and intuitive adjustment of the phase bias voltage value of the passive optical network modulator based on this spectrum.

[0065] In one specific embodiment, the method for adjusting the phase bias value of the passive optical network modulator is described in detail. Specifically, step 104 includes the following steps: The phase bias voltage of the passive optical network modulator is adjusted based on the power difference between the lowest power of the main sideband and the highest power of the secondary sideband.

[0066] Specifically, the main sideband refers to the high-power frequency band on the spectrum that carries effective signal energy, while the secondary sideband is a low-power mirror band on the other side of the spectrum caused by phase bias inaccuracies. The power difference is calculated as follows: First, determine the frequency range of the main sideband on the spectrometer's display interface, and find the point with the lowest power within this range, recording its power value; this is the minimum power of the main sideband. Next, determine the frequency range of the secondary sideband, and find the point with the highest power within this range, recording its peak power; this is the maximum power of the secondary sideband. Finally, subtract the minimum power value of the main sideband from the maximum power value of the secondary sideband; the resulting difference is the power difference used for judgment. During the adjustment process, the operator or automatic control logic continuously fine-tunes the phase bias value applied to the passive optical network modulator and observes the changes in this power difference in real time.

[0067] The above steps provide a precise and unambiguous quantitative target for optimizing the phase bias. By comparing the lowest power of the main sideband with the highest power of the secondary sideband, it is ensured that even the weakest part of the signal is far stronger than the strongest part of the interference, thus achieving a very high sideband rejection ratio and signal purity. This criterion eliminates the reliance on operator experience during adjustment, instead basing it on a clear and repeatable physical quantity. This not only significantly improves the accuracy of the phase bias setting but also guarantees the high quality of the final output optical signal.

[0068] In one possible implementation, after the phase bias adjustment process is completed, the method needs to solidify the adjustment result to ensure that the modulator can operate stably in optimal condition in subsequent operations. Therefore, after step 104, the method further includes: The adjusted phase bias value is determined as the optimal phase bias value.

[0069] Specifically, the adjusted phase bias value refers to the voltage value at which the power difference between the main and secondary sidebands in the spectrum first exceeds a preset threshold in the previous adjustment step. The optimal phase bias value represents the bias setting that enables the orthogonality of the IQ modulator output signal to reach its best or near-optimal state.

[0070] When the monitoring system determines that the power difference meets the requirements, the control logic immediately stops further adjustment of the phase bias. At this point, the voltage value applied to the modulator's phase bias pin is read and locked. This locked voltage value is then stored in the non-volatile memory of the transmitting device as a calibration parameter for the modulator. Thereafter, the transmitting device will continuously use this stored voltage value as the modulator's operating bias.

[0071] Through the above steps, the obtained optimal phase bias value is stored and solidified, ensuring that the passive optical network modulator can continuously and stably operate at the found optimal phase bias value during subsequent normal data transmission. This not only guarantees the high purity and low distortion of the generated optical signal, but also ensures the high performance and high reliability of the entire 100G+ PON system, avoiding performance degradation caused by bias drift.

[0072] Reference Figure 7 , Figure 7 This is a schematic diagram of the phase bias optimization device for a passive optical network modulator provided by the present invention. The device includes: The first acquisition module is used to acquire single-sideband signals; The first processing module is used to drive a passive optical network modulator with a single sideband signal and modulate the optical carrier of the passive optical network modulator to obtain a modulated optical signal. The second acquisition module is used to acquire the spectrum of the modulated optical signal; The second processing module is used to adjust the phase bias voltage of the passive optical network modulator according to the power difference between the main sideband and the secondary sideband in the spectrum, until it is determined that the spectrum of the modulated optical signal obtained after adjustment exhibits single-sideband characteristics.

[0073] In one possible implementation, the second processing module is further configured to determine that the power difference between the main sideband and the secondary sideband in the spectrum of the modulated optical signal obtained after adjustment is greater than a preset threshold.

[0074] In one possible implementation, the second processing module is further configured to adjust the phase bias value of the passive optical network modulator based on the power difference between the lowest power of the main sideband and the highest power of the secondary sideband.

[0075] In one possible implementation, the first acquisition module is further configured to: Generate a double-sided charged signal; The double-sided charged signal is phase-shifted to generate an orthogonal signal, wherein each frequency component of the orthogonal signal has a 90-degree phase difference with the corresponding frequency component of the double-sided charged signal. Acquire a first carrier signal and a second carrier signal, wherein the first carrier signal and the second carrier signal are orthogonal to each other; The double-sided charged signal is mixed with the first carrier signal to obtain the first mixed signal; The quadrature signal is mixed with the second carrier signal to obtain the second mixed signal; The first mixing signal and the second mixing signal are combined to obtain a single-sideband signal.

[0076] In one possible implementation, the second acquisition module is further configured to: A preset ratio of optical signal is separated from the modulated optical signal by a preset beam splitter; A preset ratio of light signal is input into a spectrometer for real-time spectral monitoring to obtain the spectrum.

[0077] It should be noted that the phase bias optimization device for passive optical network modulators provided by the present invention can execute the phase bias optimization method for passive optical network modulators of any of the above embodiments during specific operation, which will not be elaborated in this embodiment.

[0078] Figure 8 This is a schematic diagram of the structure of the electronic device provided by the present invention, such as... Figure 8 As shown, the electronic device may include: a processor 1110, a communication interface 1120, a memory 1130, and a communication bus 1140. The processor 1110, communication interface 1120, and memory 1130 communicate with each other via the communication bus 1140. The processor 1110 can call logic instructions in the memory 1130 to execute a phase bias optimization method for a passive optical network modulator. This method includes: acquiring a single-sideband signal; using the single-sideband signal to drive the passive optical network modulator and modulating the optical carrier of the passive optical network modulator to obtain a modulated optical signal; acquiring the spectrum of the modulated optical signal; and adjusting the phase bias value of the passive optical network modulator according to the power difference between the main sideband and the secondary sideband in the spectrum until it is determined that the spectrum of the modulated optical signal obtained after adjustment exhibits single-sideband characteristics.

[0079] Furthermore, the logical instructions in the aforementioned memory 1130 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0080] On the other hand, the present invention also provides a computer program product, which includes a computer program stored on a non-transitory computer-readable storage medium. The computer program includes program instructions. When the program instructions are executed by a computer, the computer is able to execute the phase bias optimization method for the passive optical network modulator provided in the above embodiments. The method includes: acquiring a single-sideband signal; driving the passive optical network modulator with the single-sideband signal and modulating the optical carrier of the passive optical network modulator to obtain a modulated optical signal; acquiring the spectrum of the modulated optical signal; and adjusting the phase bias value of the passive optical network modulator according to the power difference between the main sideband and the secondary sideband in the spectrum until it is determined that the spectrum of the modulated optical signal obtained after adjustment exhibits single-sideband characteristics.

[0081] Furthermore, the present invention also provides a non-transitory computer-readable storage medium storing a computer program thereon. When executed by a processor, the computer program implements a phase bias optimization method for a passive optical network modulator provided in the above embodiments. The method includes: acquiring a single-sideband signal; driving the passive optical network modulator with the single-sideband signal and modulating the optical carrier of the passive optical network modulator to obtain a modulated optical signal; acquiring the spectrum of the modulated optical signal; and adjusting the phase bias value of the passive optical network modulator according to the power difference between the main sideband and the secondary sideband in the spectrum until it is determined that the spectrum of the modulated optical signal obtained after adjustment exhibits single-sideband characteristics.

[0082] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0083] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, 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 can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., including several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods of various embodiments or some parts of embodiments.

[0084] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for optimizing the phase bias voltage of a passive optical network modulator, characterized in that, include: Acquire single-sideband signal; The single-sideband signal is used to drive the passive optical network modulator, and the optical carrier of the passive optical network modulator is modulated to obtain a modulated optical signal; Obtain the spectrum of the modulated optical signal; Based on the power difference between the main sideband and the secondary sideband in the spectrum, the phase bias value of the passive optical network modulator is adjusted until it is determined that the spectrum of the modulated optical signal obtained after adjustment exhibits single-sideband characteristics.

2. The phase bias optimization method for a passive optical network modulator according to claim 1, characterized in that, The determination that the spectrum of the modulated optical signal obtained after adjustment exhibits single-sideband characteristics includes: It is determined that the power difference between the main sideband and the secondary sideband in the spectrum of the modulated optical signal obtained after adjustment is greater than a preset threshold.

3. The phase bias optimization method for a passive optical network modulator according to claim 1, characterized in that, The step of adjusting the phase bias value of the passive optical network modulator based on the power difference between the main sideband and the secondary sideband in the spectrum includes: The phase bias value of the passive optical network modulator is adjusted based on the power difference between the lowest power of the main sideband and the highest power of the secondary sideband.

4. The phase bias optimization method for a passive optical network modulator according to claim 1, characterized in that, The acquisition of the single-sideband signal includes: Generate a bilateral charged signal; the bilateral charged signal is a function related to a time variable; The single-sided charged signal is obtained by convolving the bilateral charged signal with the unit impulse response; wherein the unit impulse response is the reciprocal of the product of the time variable and pi.

5. The phase bias optimization method for a passive optical network modulator according to claim 4, characterized in that, The bilateral charged signal is an electrical signal with an arbitrary baud rate.

6. The phase bias optimization method for a passive optical network modulator according to claim 1, characterized in that, The acquisition of the spectrum of the modulated optical signal includes: A preset proportion of optical signal is separated from the modulated optical signal by a preset beam splitter; The preset ratio of light signal is input into a spectrometer for real-time spectral monitoring to obtain the spectrum.

7. The phase bias optimization method for a passive optical network modulator according to claim 6, characterized in that, The execution of the real-time spectral monitoring is triggered by at least one of the following methods: Execute periodically at preset time intervals; or An event is triggered when the performance parameters of the passive optical network are detected to deteriorate beyond a preset threshold; the performance parameters include at least one of bit error rate, error vector amplitude, or signal-to-noise ratio.

8. A phase bias optimization device for a passive optical network modulator, characterized in that, include: The first acquisition module is used to acquire single-sideband signals; The first processing module is used to drive the passive optical network modulator with the single sideband signal and modulate the optical carrier of the passive optical network modulator to obtain a modulated optical signal. The second acquisition module is used to acquire the spectrum of the modulated optical signal; The second processing module is used to adjust the phase bias value of the passive optical network modulator according to the power difference between the main sideband and the secondary sideband in the spectrum, until it is determined that the spectrum of the modulated optical signal obtained after adjustment exhibits single-sideband characteristics.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that, When the processor executes the computer program, it implements the phase bias optimization method for the passive optical network modulator as described in any one of claims 1 to 7.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the phase bias optimization method for the passive optical network modulator as described in any one of claims 1 to 7.

11. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the phase bias optimization method for the passive optical network modulator as described in any one of claims 1 to 7.

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