Signal processing method, network device and storage medium

Abstract

The present application relates to the technical field of optical fiber communication, and particularly relates to a signal processing method, network equipment and a storage medium, the signal processing method comprising: obtaining a to-be-input signal of a laser; performing pre-processing on the to-be-input signal to eliminate chirp according to a preset signal pre-processing strategy, obtaining a target signal, and inputting the target signal into the laser. The technical scheme of the embodiment of the present application can eliminate or reduce chirp in the optical signal output by the laser by performing pre-processing on the to-be-input signal to eliminate chirp according to the signal pre-processing strategy, thereby improving the transmission performance of the optical fiber communication link.

Description

Technical Field

[0001] This invention relates to the field of optical fiber communication technology, and in particular to a signal processing method, network device, and storage medium. Background Technology

[0002] In optical fiber communication links, chirp accompanies the transmission of optical pulses. Chirp is primarily caused by dynamic changes in the refractive index of the medium due to the dynamic modulation of the electrical signal, which in turn causes dynamic changes in the phase of the optical signal propagating through the medium, manifested as dynamic changes in the optical signal frequency. In optical fiber communication links, chirp degrades transmission performance; therefore, eliminating or reducing chirp in optical signals is a pressing issue that needs to be addressed. Summary of the Invention

[0003] This invention provides a signal processing method, network device, and storage medium. By performing chirp-eliminating preprocessing on the input signal according to a signal preprocessing strategy, chirp in the optical signal output by the laser can be eliminated or reduced, thereby improving the transmission performance of the optical fiber communication link.

[0004] In a first aspect, embodiments of the present invention provide a signal processing method applied in a network device, the method comprising: acquiring a signal to be input from a laser; performing chirp-eliminating preprocessing on the signal to be input according to a preset signal preprocessing strategy to obtain a target signal, and inputting the target signal into the laser.

[0005] Secondly, embodiments of the present invention also provide a network device, the network device including an optical line terminal or an optical network unit, the optical line terminal or the optical network unit including a processor and a memory; the memory is used to store a program; the processor is used to call the program in the memory to implement the signal processing method as described above.

[0006] Thirdly, embodiments of the present invention also provide a storage medium for readable storage, wherein the storage medium stores one or more programs, which can be executed by one or more processors to implement the signal processing method described above.

[0007] This invention discloses a signal processing method, network device, and storage medium. By acquiring the input signal of a laser, the input signal can be preprocessed to eliminate chirp before being input into the laser. By performing chirp elimination preprocessing on the input signal according to a preset signal preprocessing strategy, the obtained target signal can be input into the laser, thereby eliminating or reducing chirp in the optical signal output by the laser and improving the transmission performance of the optical fiber communication link.

[0008] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit the invention. Attached Figure Description

[0009] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0010] Figure 1 This is a schematic diagram of the structure of an optical fiber communication link provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of a network device provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of a network device provided in an embodiment of the present invention; Figure 4 This is a schematic flowchart of a signal processing method provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of the waveform of an input signal provided in an embodiment of the present invention; Figure 6 This is a schematic diagram of the waveform of a filtered target signal provided by an embodiment of the present invention; Figure 7 This is a schematic diagram of another filtered target signal waveform provided by an embodiment of the present invention; Figure 8 This is a schematic flowchart illustrating a sub-step for filtering and canceling an input signal according to an embodiment of the present invention. Figure 9 This is a schematic diagram of a filtering process for an input signal provided in an embodiment of the present invention; Figure 10 This is a schematic flowchart illustrating a sub-step for adjusting the power value of an input signal according to an embodiment of the present invention; Figure 11 This is a schematic flowchart illustrating another sub-step for adjusting the power value of the input signal provided in an embodiment of the present invention; Figure 12 This is a spectral diagram of an input signal provided in an embodiment of the present invention; Figure 13 This is a schematic flowchart illustrating a sub-step for buffering an input signal according to an embodiment of the present invention; Figure 14 This is a schematic diagram of a waveform for buffering an input signal, provided by an embodiment of the present invention. Detailed Implementation

[0011] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0012] The flowchart shown in the attached diagram is for illustrative purposes only and does not necessarily include all content and operations / steps, nor does it necessarily have to be performed in the order described. For example, some operations / steps can be broken down, combined, or partially merged, so the actual execution order may change depending on the actual situation.

[0013] It should be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0014] It should also be understood that the term “and / or” as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0015] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0016] In the following description, the use of suffixes such as "module," "part," or "unit" to denote elements is solely for the purpose of illustrative purposes and has no inherent meaning. Therefore, "module," "part," or "unit" may be used interchangeably.

[0017] Embodiments of the present invention provide a signal processing method, a network device, and a storage medium. The signal processing method can be applied to a network device, whereby chirp-eliminating preprocessing of the input signal according to a signal preprocessing strategy can eliminate or reduce chirp in the optical signal output by a laser, thereby improving the transmission performance of optical fiber communication links.

[0018] It should be noted that the signal processing method in this embodiment can be applied to a Passive Optical Network (PON). For example, the network device can be an Optical Line Terminal (OLT) or an Optical Network Unit (ONU) in a PON.

[0019] Please see Figure 1 , Figure 1 This is a schematic diagram of the structure of an optical fiber communication link provided in an embodiment of the present invention. Figure 1 As shown, an optical fiber communication link includes a transmitter, an optical fiber, and a receiver. The transmitter can be a network device; the receiver can include a photodetector and a low-pass filter.

[0020] For example, an optical line terminal or optical network unit can transmit optical signals to an optical fiber, which then transmits the signals to a receiving end.

[0021] Please see Figure 2 , Figure 2 This is a schematic diagram of a network device provided in an embodiment of the present invention. Figure 2 As shown, the network device includes a level signal generator, a low-pass filter, and a laser. The low-pass filter is located between the level signal generator and the directly modulated laser, which can be a directly modulated laser.

[0022] It should be noted that a low-pass filter is an electronic filtering device that allows signals below the cutoff frequency to pass through, but blocks signals above the cutoff frequency. Examples of low-pass filters include, but are not limited to, Butterworth filters and Chebyshev filters.

[0023] For example, a level signal generator can generate a current signal, which is then filtered by a low-pass filter and input into a direct-modulation laser; the direct-modulation laser then converts the filtered current signal into an optical signal.

[0024] It should be noted that since the current signal generated by the level signal generator is input to the direct modulated laser, the optical signal output by the direct modulated laser has chirp. Therefore, it is necessary to perform chirp removal preprocessing on the current signal in advance to eliminate or reduce the chirp in the optical signal.

[0025] Please see Figure 3 , Figure 3This is a schematic diagram of the structure of a network device provided in an embodiment of the present invention. The network device 10 may include a processor 11 and a memory 12, wherein the processor 11 and the memory 12 can be connected by a bus, such as an I2C (Inter-integrated Circuit) bus or any applicable bus.

[0026] The memory 12 may include a non-volatile storage medium and internal memory. The non-volatile storage medium may store an operating system and a computer program. The computer program includes program instructions that, when executed, cause the processor to perform any signal processing method.

[0027] The processor 11 provides computing and control capabilities to support the operation of the entire network device 10.

[0028] In one embodiment, the processor 11 is configured to run a computer program stored in the memory 12, and to perform the following steps when executing the computer program: The input signal to be acquired from the laser is obtained; according to a preset signal preprocessing strategy, the input signal is preprocessed to eliminate chirp, and the target signal is obtained and then input into the laser.

[0029] In one embodiment, the network device 10 includes a level signal generator; the processor 11, when acquiring the input signal from the laser, is configured to: Receive the digital signal generated by the level signal generator; perform digital-to-analog conversion on the digital signal to obtain the input signal.

[0030] In one embodiment, a filter exists between the level signal generator and the laser; when the processor 11 performs chirp-eliminating preprocessing on the input signal according to a preset signal preprocessing strategy to obtain the target signal, it is configured to: If the signal preprocessing strategy is to perform filtering and cancellation processing on the input signal, then the transfer function corresponding to the filter is determined, wherein the transfer function is used to filter the signal; the zeros and poles of the transfer function are interchanged to obtain the inverse transform transfer function corresponding to the transfer function; the input signal is filtered according to the inverse transform transfer function to obtain the filtered signal corresponding to the input signal; the filtered signal is filtered according to the transfer function to obtain the target signal, wherein the target signal is a square wave signal, and the optical signal output by the square wave signal after being input to the laser does not contain chirp.

[0031] In one embodiment, when the processor 11 performs chirp removal preprocessing on the input signal according to a preset signal preprocessing strategy, it is configured to: When the signal preprocessing strategy is to adjust the power value of the input signal, the power value of the input signal is adjusted to meet a preset power condition in order to eliminate the phase change caused by the chirp in the optical signal output by the laser.

[0032] In one embodiment, the input signal includes a first-level signal and a second-level signal; when the processor 11 adjusts the power value of the input signal to meet a preset power condition, it is configured to: Collect the first power value of the first level signal and the second power value of the second level signal; increase the first power value and the second power value so that both the first power value and the second power value are greater than a preset first power threshold.

[0033] In one embodiment, after acquiring the first power value of the first level signal and the second power value of the second level signal, the processor 11 is further configured to: Determine the first product between the transient chirp coefficient and the steady-state chirp coefficient; adjust the first power value and the second power value according to the preset modulation coefficient, so that the second product between the adjusted first power value and the first product is equal to the preset second power threshold, and the third product between the adjusted second power value and the first product is equal to the second power threshold.

[0034] In one embodiment, when determining the first product between the transient chirp coefficient and the steady-state chirp coefficient, the processor 11 is configured to: Obtain the first frequency offset value of the first level signal and the second frequency offset value of the second level signal; determine the first product between the transient chirp coefficient and the steady-state chirp coefficient based on the first power value and the first frequency offset value or the second power value and the second frequency offset value.

[0035] In one embodiment, when the processor 11 performs chirp-eliminating preprocessing on the input signal according to a preset signal preprocessing strategy to obtain the target signal, it is configured to: When the signal preprocessing strategy is to buffer the input signal, the rising edge processing time, falling edge processing time, and limiting value are determined; based on the rising edge processing time and the limiting value, the rising edge of the input signal is pre-rising, and based on the falling edge processing time and the limiting value, the falling edge of the input signal is over-over-processed to obtain the target signal. The rising and falling edge times of the target signal are extended to eliminate the phase change caused by chirp in the optical signal output by the laser.

[0036] In one embodiment, a filter exists between the level signal generator and the laser; before inputting the target signal into the laser, the processor 11 is further configured to: The target signal is filtered by the filter to obtain the filtered target signal.

[0037] In one embodiment, when the processor 11 inputs the target signal into the laser, it is configured to: The filtered target signal is input into the laser.

[0038] The processor 11 can be a Central Processing Unit (CPU), but it can also be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or any conventional processor.

[0039] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0040] like Figure 4 As shown, Figure 4 This is a schematic flowchart illustrating a signal processing method provided in an embodiment of the present invention. This signal processing method is applied in network devices. By performing chirp-eliminating preprocessing on the input signal according to a signal preprocessing strategy, chirp in the optical signal output by the laser can be eliminated or reduced, thereby improving the transmission performance of the optical fiber communication link. The signal processing method includes steps S101 and S102.

[0041] Step 101: Obtain the input signal from the laser.

[0042] In this embodiment of the invention, the network device includes a level signal generator, a low-pass filter, and a direct-modulation laser, which can generate an input signal. The input signal is a current signal.

[0043] In some embodiments, acquiring the input signal of the laser may include: receiving a digital signal generated by a level signal generator; and performing digital-to-analog conversion on the digital signal to obtain the input signal.

[0044] For example, a level signal generator can generate a digital signal at a 0 / 1 level; then, a digital-to-analog converter is used to convert the digital signal into an analog signal, which is the input signal.

[0045] Please see Figure 5 , Figure 5 This is a schematic diagram of the waveform of an input signal provided in an embodiment of the present invention. For example... Figure 5 As shown, before the input signal passes through the low-pass filter, the input signal is a square wave signal with a 0 / 1 level.

[0046] In this embodiment of the invention, after performing digital-to-analog conversion on the digital signal to obtain the input signal, the input signal needs to be filtered by a low-pass filter to obtain the target signal, and then the target signal is input into the direct modulation laser.

[0047] By acquiring the input signal from the laser, chirp elimination preprocessing can be performed on the input signal to avoid chirp in the optical signal generated after the target signal is input into the laser, which would affect the communication quality of the optical signal.

[0048] Please see Figure 6 and Figure 7 , Figure 6 This is a schematic diagram of the waveform of a filtered target signal provided by an embodiment of the present invention. Figure 7 This is a schematic diagram of another filtered target signal waveform provided by an embodiment of the present invention. Figure 6 and Figure 7 In the process, the input signal is filtered, and the filtered target signal is input into the laser to generate an optical signal.

[0049] It is understandable that chirp can include transient chirp and steady-state chirp. Transient chirp is caused by changes in the current in the laser, which cause changes in the carrier concentration in the resonant cavity, thus causing fluctuations in the laser frequency. Steady-state chirp is determined by the magnitude of the current signal, exists throughout the entire current signal period, and the frequency deviation it causes is directly proportional to the magnitude of the current signal.

[0050] It should be noted that, in this embodiment of the invention, the signal processing method mainly performs chirp elimination preprocessing on the current signal to eliminate or reduce transient chirp in the optical signal output by the laser; this embodiment of the invention will combine the characteristics of transient chirp in current to explain in detail how to eliminate or reduce transient chirp.

[0051] Step S102: According to the preset signal preprocessing strategy, the input signal is preprocessed to eliminate chirp, and the target signal is obtained and input into the laser.

[0052] For example, the preset signal preprocessing strategy may include at least one of the following: performing filtering and cancellation processing on the input signal; adjusting the power value of the input signal; and buffering the input signal.

[0053] It should be noted that filtering and canceling the input signal refers to canceling the filtering effect of the low-pass filter, ensuring that the target signal after low-pass filtering is consistent with the input signal before filtering, both being square wave signals with 0 / 1 levels. Since transient chirp only occurs during square wave signal transitions, its influence can be minimized. Adjusting the power value of the input signal means adjusting the power value of the 0 / 1 level of the input signal to meet preset conditions, thereby eliminating the phase change of the optical signal caused by transient chirp. Buffering the input signal involves extending the rise and fall times of the input signal, allowing the target signal to quickly return to a stable state, thus reducing transient chirp.

[0054] In this embodiment of the invention, the method of chirp removal preprocessing for the input signal will be described in detail based on different signal preprocessing strategies.

[0055] Please see Figure 8 , Figure 8 This is a schematic flowchart of a sub-step for filtering and canceling an input signal according to an embodiment of the present invention, which may specifically include the following steps S201 to S204.

[0056] Step S201: If the signal preprocessing strategy is to perform filtering and cancellation processing on the input signal, then determine the transfer function corresponding to the filter, wherein the transfer function is used to filter the signal.

[0057] For example, the frequency response characteristics of a low-pass filter can be measured using a spectrum analyzer, and its inverse function can be obtained in the frequency domain, which is the inverse transform transfer function of the transfer function.

[0058] By determining the transfer function corresponding to the low-pass filter, the zeros and poles of the transfer function can be obtained. Thus, the positions of the zeros and poles of the transfer function can be interchanged to obtain the inverse transform transfer function corresponding to the transfer function.

[0059] Step S202: Interchange the positions of the zeros and poles of the transfer function to obtain the inverse transform transfer function corresponding to the transfer function.

[0060] For example, the zp2tf function can be used to extract the zeros of the transfer function of a low-pass filter. and extreme points When the positions are interchanged, the inverse transform transfer function corresponding to the transfer function is:

[0061] For example, a low-pass filter at zero point and extreme points The representation after position swapping is ;in, and These are the new time-domain tap coefficients. These are the vector coefficients in the denominator. These are the vector coefficients on the molecule.

[0062] By swapping the zeros and poles of the transfer function, the inverse transform transfer function is obtained. The input signal can then be filtered sequentially based on the inverse transform transfer function and the original transfer function, ensuring that the filtered target signal remains consistent with the original input signal.

[0063] Step S203: Filter the input signal according to the inverse transform transfer function to obtain the filtered signal corresponding to the input signal.

[0064] Please see Figure 9 , Figure 9 This is a schematic diagram illustrating a filtering process for an input signal provided by an embodiment of the present invention. Figure 9 As shown, the input signal at node 1 is represented as The filtered signal at node 1.1 is represented as The target signal at node 2 is represented as ,in, .

[0065] For example, the input signal is filtered according to the inverse transform transfer function, and the resulting filtered signal is: .

[0066] Step S204: Filter the filtered signal according to the transfer function to obtain the target signal, wherein the target signal is a square wave signal, and the optical signal output by the square wave signal after being input into the laser does not contain chirp.

[0067] For example, by filtering the signal according to the transfer function, the target signal is obtained as follows: According to the formula With formula The input signal can be obtained. With target signal same.

[0068] In this embodiment of the invention, the input signal is a square wave signal, and the target signal is also a square wave signal.

[0069] By filtering the input signal according to the inverse transform transfer function and then filtering the filtered signal a second time using the transfer function, the target signal obtained is consistent with the input signal before filtering, both being square wave signals. This ensures that the optical signal output from the laser after the target signal is input does not contain transient chirp, thus improving the transmission performance of the optical fiber communication link.

[0070] In some embodiments, preprocessing the input signal to eliminate chirp according to a preset signal preprocessing strategy may include: when the signal preprocessing strategy is to adjust the power value of the input signal to meet a preset power condition, so as to eliminate the phase change caused by chirp in the optical signal output by the laser.

[0071] For example, the input signal includes a first level signal and a second level signal; wherein the first level signal is level 1 and the second level signal is level 0. In this embodiment of the invention, the phase change of the optical signal caused by chirp can be eliminated by adjusting the first power value corresponding to the first level signal and the second power value corresponding to the second level signal to meet a preset power condition.

[0072] Please see Figure 10 , Figure 10 This is a schematic flowchart of a sub-step for adjusting the power value of an input signal according to an embodiment of the present invention, which may specifically include the following steps S301 and S302.

[0073] Step S301: Collect the first power value of the first level signal and the second power value of the second level signal.

[0074] It should be noted that, in this embodiment of the invention, a first power value of the first level signal and a second power value of the second level signal can be acquired by a spectrometer.

[0075] For example, the first power value of the first level signal and the second power value of the second level signal can be acquired before the input signal passes through the low-pass filter; or the first power value of the first level signal and the second power value of the second level signal can be acquired after the input signal passes through the low-pass filter.

[0076] For example, the first power value can be expressed as The second power value can be expressed as: It is understandable that the first and second power values ​​change over time. Changeable.

[0077] Step S302: Increase the first power value and the second power value so that both the first power value and the second power value are greater than the preset first power threshold.

[0078] It should be noted that the expression for the phase change caused by chirping is:

[0079] In the formula, Represents the transient chirp coefficient; Represents the steady-state chirp coefficient; Indicates the first power value Or the second power value ; This indicates the phase change caused by transient chirping; This represents the phase change caused by steady-state chirping.

[0080] Understandably, based on the natural logarithm function The properties, when hour, The slope changes very little at this time. Therefore, if power Zoom in This can eliminate the phase change caused by transient chirping.

[0081] For example, the first power value can be increased by a power amplifier or a circuit amplifier. With the second power value This makes the first power value With the second power value All are greater than the preset first power threshold. At this time, and .

[0082] The preset first power threshold can be a value much greater than 1, and the specific value is not limited here. For example, the first power threshold can be 100, 1000, etc.

[0083] By increasing the first power value and the second power value so that both the first power value and the second power value are greater than the preset first power threshold, the phase change caused by transient chirp can be eliminated, thereby improving the transmission performance of the optical fiber communication link.

[0084] Please see Figure 11 , Figure 11 This is a schematic flowchart illustrating another sub-step for adjusting the power value of the input signal provided in an embodiment of the present invention. After step S301, further steps S303 and S304 may be included.

[0085] Step S303: Determine the first product between the transient chirp coefficient and the steady-state chirp coefficient.

[0086] In some embodiments, determining the first product between the transient chirp coefficient and the steady-state chirp coefficient may include: obtaining a first frequency offset value of a first level signal and a second frequency offset value of a second level signal; and determining the first product between the transient chirp coefficient and the steady-state chirp coefficient based on a first power value and the first frequency offset value or a second power value and the second frequency offset value.

[0087] It should be noted that frequency offset refers to the deviation of a fixed FM wave frequency from one side to the other, which can be expressed as... .

[0088] For example, the first frequency offset of the first level signal and the second frequency offset of the second level signal can be determined by measuring the spectrum of the input signal and then based on the spectrum.

[0089] Please see Figure 12 , Figure 12 This is a spectral diagram of an input signal provided in an embodiment of the present invention. For example... Figure 12 As shown, the horizontal axis corresponding to the highest peak at 10 GHz represents the first frequency offset of the first-level signal; the horizontal axis corresponding to the second peak at 1.5 GHz represents the second frequency offset of the second-level signal. Of course, the first and second frequency offset values ​​can be determined based on the actual waveform of the spectrum, and the specific values ​​are not limited here.

[0090] For example, the relationship between frequency offset and power is shown below:

[0091] According to the above formula, we can obtain... .

[0092] For example, it can be based on a first power value With the first frequency offset Determine the first product between the transient chirp coefficient and the steady-state chirp coefficient. .

[0093] For example, it can also be based on the second power value With the second frequency offset Determine the first product between the transient chirp coefficient and the steady-state chirp coefficient. .

[0094] By obtaining the first frequency offset value of the first level signal and the second frequency offset value of the second level signal, the first product between the transient chirp coefficient and the steady-state chirp coefficient can be determined based on the relationship between the frequency offset value and the power.

[0095] Step S304: Adjust the first power value and the second power value according to the preset modulation coefficient, so that the second product between the adjusted first power value and the first product is equal to the preset second power threshold, and the third product between the adjusted second power value and the first product is equal to the second power threshold.

[0096] It should be noted that the expression for the phase change caused by chirping... It can be concluded that if ,Right now This can eliminate the phase change caused by steady-state chirping.

[0097] in, It is a positive integer. For example, the preset second power threshold is... , where positive integers The value can be set according to the actual situation; no specific value is specified here.

[0098] It should be noted that the modulation coefficient refers to the ratio of the amplitude of the modulating signal to that of the carrier signal. In this embodiment of the invention, the modulation coefficient can be set according to the actual situation, and the specific value is not limited here.

[0099] For example, the modulation coefficient can be expressed as Modulation coefficient With the first power value Second power value The relationship between them is:

[0100] For example, modulation coefficient The value can be 0.85, or any other value; there are no restrictions here. The first power value is adjusted using the above formula. Second power value This makes the adjusted first power value with the first product The second product between them satisfies ; so that the adjusted second power value with the first product The third product between them satisfies .

[0101] By adjusting the first power value and the second power value according to the preset modulation coefficient, the product of the first power value, the second power value and the first product are all equal to the preset second power threshold. This can eliminate the phase change caused by steady-state chirp, thereby improving the transmission performance of the optical fiber communication link.

[0102] Please see Figure 13 , Figure 13This is a schematic flowchart of a sub-step for buffering an input signal according to an embodiment of the present invention, which may specifically include the following steps S401 and S402.

[0103] Step S401: When the signal preprocessing strategy is to buffer the input signal, determine the rising edge processing time, falling edge processing time, and amplitude limiting value.

[0104] For example, the rising edge processing time can be expressed as The falling edge processing time can be expressed as: The amplitude limit can be expressed as: Among them, the rising edge processing time Falling edge processing time and amplitude limit The value can be set according to the actual situation; no specific value is specified here.

[0105] For example, rising edge processing time It can be 7ms, the falling edge processing time. It can be 8ms; the limiting value can be 0.05dB, 0.1dB, or 0.15dB, etc.

[0106] Step S402: Based on the rising edge processing time and the limiting value, perform early rising processing on the rising edge of the signal to be input, and based on the falling edge processing time and the limiting value, perform overshoot processing on the falling edge of the signal to be input, to obtain the target signal. The rising and falling edge times of the target signal are extended to eliminate the phase change caused by chirp in the optical signal output by the laser.

[0107] It should be noted that by performing early rising processing on the rising edge of the input signal and overshoot processing on the falling edge, the phase change caused by chirp in the optical signal can be eliminated, thereby improving the transmission performance of the optical fiber communication link.

[0108] Please see Figure 14 , Figure 14 This is a schematic diagram of a waveform for buffering an input signal, provided by an embodiment of the present invention. Figure 14 As shown, the processing time can be determined based on the rising edge. With limit value The rising edge of the input signal is processed in advance; the falling edge processing time can be adjusted accordingly. With limit value The falling edge of the input signal is overshooted to obtain the buffered target signal.

[0109] By buffering the input signal and extending the time of its rising and falling edges, the time it takes for the input signal to return to a stable state after a level transition can be shortened, thereby reducing the bit error rate.

[0110] In some embodiments, before inputting the target signal into the laser, the method further includes: filtering the target signal using a filter to obtain a filtered target signal.

[0111] It should be noted that the target signal here refers to the target signal obtained by adjusting the power value of the input signal before it passes through the low-pass filter, or the target signal obtained by buffering the input signal.

[0112] In some embodiments, inputting the target signal into the laser may include inputting a filtered target signal into the laser.

[0113] For example, the target signal filtered by a low-pass filter is input into a direct-modulation laser, which then converts the target signal into an optical signal.

[0114] By filtering the target signal using a low-pass filter, useless high-frequency signals can be filtered out, thus improving the transmission performance of the fiber optic communication link.

[0115] The signal processing method, network device, and storage medium provided in the above embodiments, by acquiring the input signal of the laser, can subsequently perform chirp elimination preprocessing on the input signal to avoid chirp in the output optical signal after the target signal is input to the laser, thereby affecting the quality of the optical signal; by determining the transfer function corresponding to the low-pass filter, the zeros and poles of the transfer function can be obtained, thereby enabling the zeros and poles of the transfer function to be interchanged to obtain the inverse transform transfer function corresponding to the transfer function; by filtering the input signal according to the inverse transform transfer function, and by performing secondary filtering on the filtered signal through the transfer function, the obtained target signal is consistent with the input signal before filtering, both being square wave signals, thereby ensuring that the optical signal output after the target signal is input to the laser does not contain transient chirp, improving the transmission performance of the optical fiber communication link; by increasing the first power value and the second power value, so that both the first power value and the second power value are greater than the preset... A first power threshold is set to eliminate phase changes caused by transient chirp and improve the transmission performance of the optical fiber communication link. By obtaining the first frequency offset value of the first level signal and the second frequency offset value of the second level signal, the first product between the transient chirp coefficient and the steady-state chirp coefficient can be determined according to the relationship between the frequency offset value and the power. By adjusting the first power value and the second power value according to the preset modulation coefficient, the product of the first power value, the second power value and the first product is equal to the preset second power threshold, which can eliminate phase changes caused by steady-state chirp and improve the transmission performance of the optical fiber communication link. By performing early rise processing on the rising edge of the input signal and overshoot processing on the falling edge, phase changes caused by chirp in the optical signal can be eliminated, improving the transmission performance of the optical fiber communication link. By filtering the target signal according to the low-pass filter, useless high-frequency signals can be filtered out, improving the transmission performance of the optical fiber communication link.

[0116] An embodiment of the present invention also provides a storage medium for readable storage, the storage medium storing a program, the program including program instructions, the processor executing the program instructions to implement any of the signal processing methods provided in the embodiments of the present invention.

[0117] For example, when the program is loaded by the processor, it can perform the following steps: The input signal to be acquired from the laser is obtained; according to a preset signal preprocessing strategy, the input signal is preprocessed to eliminate chirp, and the target signal is obtained and then input into the laser.

[0118] The storage medium can be an internal storage unit of the network device described in the foregoing embodiments, such as the hard drive or memory of the network device. Alternatively, the storage medium can be an external storage device of the network device, such as a plug-in hard drive, Smart Media Card (SMC), Secure Digital Card (SD Card), or Flash Card equipped on the network device.

[0119] Those skilled in the art will understand that all or some of the steps in the methods disclosed above, as well as the functional modules / units in the systems and devices, can be implemented as software, firmware, hardware, or suitable combinations thereof.

[0120] In hardware implementations, the division between functional modules / units mentioned in the above description does not necessarily correspond to the division of physical components; for example, a physical component may have multiple functions, or a function or step may be performed collaboratively by several physical components. Some or all physical components may be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit. Such software may be distributed on a storable medium, which may include computer storage media (or non-transitory media) and communication media (or transient media). As is known to those skilled in the art, the term storage medium includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules, or other data). Computer storage media include, but are not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disc (DVD) or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and is accessible to a computer. Furthermore, as is known to those skilled in the art, communication media typically contain computer-readable instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.

[0121] The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but this does not limit the scope of the invention. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and spirit of the present invention should be within the scope of the present invention.

Claims

1. A signal processing method applied in a network device, the method comprising: Acquire the input signal from the laser; According to a preset signal preprocessing strategy, the input signal is preprocessed to eliminate chirp, resulting in a target signal, which is then input into the laser. The chirping includes transient chirping and steady-state chirping; The network device includes a level signal generator; acquiring the input signal from the laser includes: Receive the digital signal generated by the level signal generator; The digital signal is converted from digital to analog to obtain the input signal; The signal preprocessing strategy includes at least one of the following: The input signal is filtered and canceled. Adjust the power value of the input signal; The input signal is buffered.

2. The signal processing method according to claim 1, characterized in that, A filter exists between the level signal generator and the laser; The step of performing chirp-eliminating preprocessing on the input signal according to a preset signal preprocessing strategy to obtain the target signal includes: If the signal preprocessing strategy is to perform filtering and cancellation processing on the input signal, then the transfer function corresponding to the filter is determined, wherein the transfer function is used to filter the signal; The zeros and poles of the transfer function are interchanged to obtain the inverse transform transfer function corresponding to the transfer function; The input signal is filtered according to the inverse transform transfer function to obtain the filtered signal corresponding to the input signal. The target signal is obtained by filtering the filter signal according to the transfer function, wherein the target signal is a square wave signal and the optical signal output by the square wave signal after being input into the laser does not contain chirp.

3. The signal processing method according to claim 1, characterized in that, The step of performing chirp removal preprocessing on the input signal according to a preset signal preprocessing strategy includes: When the signal preprocessing strategy is to adjust the power value of the input signal, the power value of the input signal is adjusted to meet a preset power condition in order to eliminate the phase change caused by the chirp in the optical signal output by the laser.

4. The signal processing method according to claim 3, characterized in that, The input signal includes a first-level signal and a second-level signal. Adjusting the power value of the input signal to meet a preset power condition includes: Collect the first power value of the first level signal and the second power value of the second level signal; Increase the first power value and the second power value so that both the first power value and the second power value are greater than a preset first power threshold; the first power threshold is a power value that can eliminate the phase change caused by the transient chirp.

5. The signal processing method according to claim 4, characterized in that, After acquiring the first power value of the first level signal and the second power value of the second level signal, the method further includes: Determine the first product between the transient chirp coefficient and the steady-state chirp coefficient; According to a preset modulation coefficient, the first power value and the second power value are adjusted so that the second product between the adjusted first power value and the first product is equal to a preset second power threshold, and the third product between the adjusted second power value and the first product is equal to the second power threshold; the first power threshold is a power value that can eliminate the phase change caused by the steady-state chirp.

6. The signal processing method according to claim 5, characterized in that, Determining the first product between the transient chirp coefficient and the steady-state chirp coefficient includes: Obtain the first frequency offset value of the first level signal and the second frequency offset value of the second level signal; The first product between the transient chirp coefficient and the steady-state chirp coefficient is determined based on the ratio of the first frequency offset value to the first power value, or the ratio of the second frequency offset value to the second power value.

7. The signal processing method according to claim 1, characterized in that, The step of performing chirp-eliminating preprocessing on the input signal according to a preset signal preprocessing strategy to obtain the target signal includes: When the signal preprocessing strategy is to buffer the input signal, the rising edge processing time, falling edge processing time, and amplitude limiting value are determined. Based on the rising edge processing time and the limiting value, the rising edge of the input signal is processed to advance the rise time, and based on the falling edge processing time and the limiting value, the falling edge of the input signal is processed to overshoot the falling edge, thereby obtaining the target signal. The rising and falling edge times of the target signal are extended to eliminate the phase change caused by chirp in the optical signal output by the laser.

8. The signal processing method according to any one of claims 3-7, characterized in that, A filter exists between the level signal generator and the laser; before inputting the target signal into the laser, the method further includes: The target signal is filtered by the filter to obtain the filtered target signal; The step of inputting the target signal into the laser includes: The filtered target signal is input into the laser.

9. A network device, characterized in that, The network device includes an optical line terminal or an optical network unit, and the optical line terminal or the optical network unit includes a processor and a memory. The memory is used to store programs; The processor is configured to execute the program and, when executing the program, implement the signal processing method as described in any one of claims 1 to 8.

10. A storage medium for readable storage, characterized in that, The storage medium stores one or more programs, which can be executed by one or more processors to implement the signal processing method as described in any one of claims 1 to 8.

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