Channel adaptive modulation method and device based on lookup table and storage medium

Abstract

The application discloses a channel adaptive modulation method and device based on a lookup table and a storage medium. The method comprises the following steps: determining an optical network unit and a corresponding channel; querying a lookup table according to the optical network unit and the channel to obtain a geometrically shaped constellation diagram; modulating original data by using the geometrically shaped constellation diagram to obtain a modulation signal; and sending the modulation signal to the optical network unit. In the embodiment, the geometrically shaped constellation diagram matched with the optical network unit and the channel is obtained by querying the lookup table, and the original data is modulated by using the diagram. The process uses a pre-stored mapping relationship to replace real-time complex calculation, thereby reducing the hardware cost of signal processing. Meanwhile, the application of the geometrically shaped constellation diagram optimizes the signal constellation distribution, quantifies the matching degree of the signal and the link, reduces the processing delay of the optical line terminal, better utilizes the channel resources due to the matching of the transmission rate and the channel condition, and therefore effectively improves the transmission capacity and the transmission efficiency of the passive optical network.

Description

Technical Field

[0001] This application relates to the field of optical communication technology, and in particular to a channel adaptive modulation method, apparatus and storage medium based on lookup table. Background Technology

[0002] In recent years, with the rise of 5G mobile, artificial intelligence, cloud networking, and high-definition video streaming services, the bandwidth demand for optical access networks has increased dramatically. The International Telecommunication Union Telecommunication Standardization Sector (ITU-T) has released its latest generation PON (Passive Optical Network) recommendation (G.9804), with a target rate of 50 Gb / s per wavelength. As PONs develop towards 50 Gb / s and above per wavelength, PON systems based on intensity modulation and direct detection (IM / DD) struggle to meet power budget requirements in high-speed systems due to factors such as poor receiver sensitivity and power fading caused by dispersion at high speeds and long transmission distances.

[0003] Coherent Passive Optical Networks (CPONs) have attracted widespread attention due to their high spectral efficiency, high sensitivity, and high flexibility. Coherent technology employs advanced digital signal processing (DSP) capabilities and multidimensional modulation techniques, significantly improving transmission capacity, access capacity, and transmission distance, and is considered a strong candidate technology for future PONs. Its transmission rate is greatly enhanced because it can easily utilize amplitude and phase information to achieve high-order modulation.

[0004] Traditional PON systems provide a uniform peak data rate for ONUs (Optical Network Units) under different channel conditions. Network capacity is limited by the worst-performing link, thus still limiting the total capacity of the system.

[0005] To address this issue, a probabilistic shaping scheme is typically used to adjust the channel rate. However, probabilistic shaping is usually implemented using the Constant Composition Distribution Matching (CCDM) algorithm, whose hardware implementation is too complex for PON systems. Summary of the Invention

[0006] This application provides a channel adaptive modulation method, apparatus, and storage medium based on lookup tables, which can improve the transmission capacity and transmission efficiency of passive optical networks.

[0007] In a first aspect, embodiments of this application provide a channel adaptive modulation method based on a lookup table, applied to an optical line terminal (OLT), comprising: Determine the optical network unit and the channel corresponding to the optical network unit; Based on the optical network unit and the pre-stored lookup table for the channel query, the corresponding geometrically shaped constellation diagram is obtained; The original data is modulated using the geometrically shaped constellation diagram to obtain a modulated signal; The modulated signal is sent to the optical network unit.

[0008] In conjunction with the first aspect, in one implementation, the lookup table is established through the following steps: Obtain the signal-to-noise ratio of the channel of the optical network unit; Select the modulation order based on the signal-to-noise ratio; A geometrically shaped constellation design is performed using gradient calculation based on generalized mutual information combined with a trust region algorithm, resulting in a geometrically shaped constellation diagram. A lookup table is constructed based on the geometrically shaped constellation diagram, the corresponding channels, and the optical network units.

[0009] In conjunction with the first aspect, in one embodiment, obtaining the signal-to-noise ratio of the channel of the optical network unit includes: Send training sequences to the optical network unit; The signal-to-noise ratio (SNR) fed back by the optical network unit is obtained by the optical network unit based on the received training sequence.

[0010] Secondly, embodiments of this application provide a channel adaptive modulation method based on a lookup table, applied to an optical network unit (ONU), comprising: Receive modulated signals sent by the optical line terminal; Obtain the geometrically shaped constellation diagram corresponding to the modulation signal; The modulated signal is demodulated using the geometrically shaped constellation diagram to obtain the original data.

[0011] In conjunction with the second aspect, in one embodiment, the method further includes: Receive the training sequence sent by the optical line terminal; Estimate the signal-to-noise ratio of the channel based on the training sequence; The signal-to-noise ratio is fed back to the optical line terminal so that the optical line terminal can build or update its stored lookup table based on the signal-to-noise ratio.

[0012] In conjunction with the second aspect, in one embodiment, obtaining the geometrically shaped constellation diagram corresponding to the modulation signal includes: Read a pre-configured geometric constellation diagram from local memory, or receive a geometric constellation diagram sent by the optical line terminal.

[0013] Thirdly, embodiments of this application provide a channel adaptive modulation apparatus based on a lookup table, applied to an optical line terminal (OLT), comprising: A channel confirmation module is used to determine the optical network unit and the channel corresponding to the optical network unit. The first constellation diagram acquisition module is used to obtain the corresponding geometrically shaped constellation diagram by querying a pre-stored lookup table based on the optical network unit and the channel. A signal modulation module is used to modulate the original data using the geometrically shaped constellation diagram to obtain a modulated signal; A signal transmission module is used to transmit the modulated signal to the optical network unit.

[0014] Fourthly, embodiments of this application provide a channel adaptive modulation device based on a lookup table, applied to an optical network unit (ONU), comprising: A signal receiving module, which is used to receive modulated signals sent by the optical line terminal; The second constellation diagram acquisition module is used to acquire the geometrically shaped constellation diagram corresponding to the modulation signal; A signal demodulation module is used to demodulate the modulated signal using the geometrically shaped constellation diagram to obtain the original data.

[0015] Fifthly, embodiments of this application provide a lookup table-based channel adaptive modulation device, including a processor, a memory, and a lookup table-based channel adaptive modulation program stored in the memory and executable by the processor, wherein when the lookup table-based channel adaptive modulation program is executed by the processor, it implements the steps of the lookup table-based channel adaptive modulation method as described in any of the preceding claims.

[0016] In a sixth aspect, embodiments of this application provide a computer-readable storage medium storing a lookup table-based channel adaptive modulation program, wherein when the lookup table-based channel adaptive modulation program is executed by a processor, it implements the steps of the lookup table-based channel adaptive modulation method as described in any of the preceding claims.

[0017] The beneficial effects of the technical solution provided in this application include: This application provides a channel adaptive modulation method, apparatus, and storage medium based on a lookup table. This embodiment obtains a geometrically shaped constellation diagram matching the optical network unit and the channel by querying a pre-stored lookup table, and then uses this diagram to modulate the original data. This process uses pre-stored mapping relationships to replace complex real-time calculations, reducing the hardware overhead of signal processing. Simultaneously, the application of the geometrically shaped constellation diagram optimizes the signal constellation distribution and quantifies the matching degree between the signal and the link. While reducing the processing latency of the optical line terminal, it also better utilizes channel resources because the transmission rate matches the channel conditions, thus effectively improving the transmission capacity and efficiency of the passive optical network. Attached Figure Description

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

[0019] Figure 1 This is a flowchart illustrating an embodiment of the channel adaptive modulation method based on lookup tables in this application; Figure 2 This is an example diagram of the PON system architecture of this application; Figure 3 This application includes a constellation diagram with multiple ONUs and multiple channels, and provides an example diagram for representation. Figure 4 This is a flowchart illustrating another embodiment of the channel adaptive modulation method based on lookup tables in this application; Figure 5 This is a functional block diagram of an embodiment of the channel adaptive modulation device based on a lookup table according to this application; Figure 6 This is a functional block diagram of another embodiment of the channel adaptive modulation apparatus based on a lookup table in this application; Figure 7 This is a schematic diagram of the hardware structure of the channel adaptive modulation device based on a lookup table involved in the embodiments of this application. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0021] In a first aspect, embodiments of this application provide a channel adaptive modulation method based on a lookup table, applied to an optical line terminal (OLT).

[0022] In one embodiment, reference is made to Figure 1 , Figure 1 This is a flowchart illustrating an embodiment of the channel adaptive modulation method based on a lookup table according to this application. Figure 1 As shown, the channel adaptive modulation method based on lookup tables includes: S101: Determine the optical network unit and the channel corresponding to the optical network unit.

[0023] Regarding the specific implementation of determining the optical network unit and its corresponding channel in step S101, this embodiment can adopt conventional methods in existing passive optical network protocols. For example, the optical line terminal can maintain a registration information table and a bandwidth allocation table for optical network units. When data to be transmitted arrives, the optical line terminal parses the destination identifier of the data (such as Logical Link Identifier (LLID) or Media Access Control Address (MAC)) and matches it to the target optical network unit. At the same time, according to the current resource allocation strategy, it obtains the physical channel (such as a specific wavelength or time slot) allocated to the target optical network unit.

[0024] For example, the optical line terminal identifies the target optical network unit as optical network unit 1 based on the destination address of the data to be transmitted, and determines that the wavelength channel currently used by optical network unit 1 is channel 1.

[0025] S102: Obtain the corresponding geometrically shaped constellation diagram based on the optical network unit and the pre-stored lookup table of the channel query.

[0026] Compared to probabilistic shaping, geometric shaping does not introduce additional rate loss; therefore, this embodiment is a channel adaptive modulation method based on lookup table (LUT). By estimating different channel conditions, a suitable modulation format and geometrically shaped (GS) constellation diagram are obtained, and a corresponding lookup table (LUT) is established. Appropriate transmission rates, modulation formats, and shaping schemes are selected for different channel conditions, achieving channel adaptive modulation shaping and improving system transmission capacity, transmission performance, and dynamic range of received power.

[0027] For example, using optical network unit 1 and channel 1 as indices, a lookup table stored locally at the optical line terminal is searched to find the pre-calculated and stored geometrically shaped constellation diagram corresponding to the channel conditions. This constellation diagram contains the coordinate information of the signal constellation points, avoiding the need for complex algorithm calculations in real time.

[0028] S103: Modulate the original data using the geometrically shaped constellation diagram to obtain a modulated signal.

[0029] S104: Send the modulation signal to the optical network unit.

[0030] This embodiment retrieves a geometrically shaped constellation diagram matching the optical network unit and channel by querying a pre-stored lookup table, and then uses this diagram to modulate the original data. This process uses pre-stored mapping relationships to replace complex real-time calculations, reducing the hardware overhead of signal processing. Simultaneously, the application of the geometrically shaped constellation diagram optimizes the signal constellation distribution and quantifies the matching degree between the signal and the link. While reducing the processing latency of the optical line terminal, it also better utilizes channel resources because the transmission rate matches the channel conditions, thus effectively improving the transmission capacity and efficiency of the passive optical network.

[0031] This embodiment uses a lookup table to match a geometrically shaped constellation diagram adapted to the channel's signal-to-noise ratio. For channels with lower received power, the shaping gain from geometric shaping is used to improve demodulation sensitivity and lower the minimum acceptable optical power threshold. For channels with higher received power, higher-order modulation is adaptively selected to fully utilize signal quality. This differentiated adaptation mechanism allows the system to be compatible with a wider range of received optical power levels, thereby effectively improving the dynamic range of received power in the passive optical network system.

[0032] The PON system architecture designed in this application is as follows: Figure 2 As shown, taking the dual-polarization modulation transceiver approach used at both the OLT and ONU ends as an example, both the OLT and ONU transmitters consist of a light source, an IQ modulator, a digital-to-analog converter (DAC), and a transmitting DSP. Both the OLT and ONU receivers consist of a local light source (LO), a coherent receiver, an analog-to-digital converter (ADC), and a receiving DSP. The transmitting DSP generates the digital signal to be transmitted, which is converted into an analog signal by the DAC, sent to the IQ modulator for modulation, and then transmitted to the optical link via optical fiber, such as standard single-mode fiber, to the receiving end. At the receiving end, the coherent receiver photodemodulates the received signal, and the demodulated electrical signal is converted back into a digital signal by the ADC, which is then recovered in the receiving DSP.

[0033] Furthermore, in one embodiment, the lookup table is established through the following steps: S201: Obtain the signal-to-noise ratio of the channel of the optical network unit.

[0034] The Optical Line Terminal (OLT) sends a Training Sequence (TS) to multiple Optical Network Units (ONUs). The receivers on the ONU side receive the TS signals from the OLT and use the TS signals to estimate the Signal-to-Noise Ratio (SNR). The estimated SNR value is then fed back to the OLT at the transmitting end.

[0035] By obtaining the signal-to-noise ratio, the transmission quality of the current channel can be quantified, providing basic data support for selecting a suitable modulation strategy and ensuring that the modulation scheme matches the channel state.

[0036] It should be noted that, in this embodiment, the training sequence refers to a known signal sequence pre-agreed upon by the optical line terminal (OLT) and the optical network unit (ONU). The OLT sends this sequence, and the ONU receives it. By comparing the received signal with the locally stored original sequence, the ONU quantifies the channel noise and interference level, thereby estimating the signal-to-noise ratio (SNR). This training sequence can be a preamble, pilot symbol, or a specific pseudo-random sequence within a frame structure. The specific form is not limited in this embodiment, as long as it meets the requirements for channel quality estimation.

[0037] S202: Select the modulation order based on the signal-to-noise ratio.

[0038] For each channel's SNR value, the OLT first selects an appropriate modulation order, such as 2nd order QPSK, 4th order 16QAM, 5th order 32QAM, and 6th order 64QAM.

[0039] This step initially determines the signal's ability to carry information, enabling the transmission rate to be dynamically adjusted according to channel quality, thus avoiding resource waste.

[0040] S203: A geometrically shaped constellation is designed by combining gradient calculation based on generalized mutual information with a trust region algorithm, resulting in a geometrically shaped constellation diagram.

[0041] By utilizing gradient calculation of generalized mutual information combined with a trust region algorithm, the constellation point positions for a selected modulation order are optimized. This process seeks the constellation point coordinate distribution with optimal transmission performance at a specific signal-to-noise ratio, resulting in a geometrically shaped constellation diagram, which further improves spectral efficiency and noise immunity compared to conventional constellation diagrams.

[0042] S204: Construct a lookup table based on the geometrically shaped constellation diagram, the corresponding channels, and optical network units.

[0043] The calculated geometrically shaped constellation diagram is mapped to the corresponding optical network unit identifier and channel identifier, and stored in a lookup table at the optical line terminal. This eliminates the need for repeated calculations during subsequent data transmission; the optimal constellation diagram can be retrieved directly through a lookup, significantly reducing the complexity and latency of real-time processing.

[0044] Figure 3 This diagram shows an example of a constellation lookup table with multiple ONUs and multiple channels. The lookup table stores geometrically shaped constellation diagrams calculated for different channels of different ONUs, which are used to provide modulation constellation diagrams during data modulation in the data transmission phase.

[0045] Secondly, embodiments of this application provide a channel adaptive modulation method based on a lookup table, applied to an optical network unit (ONU).

[0046] In one embodiment, reference is made to Figure 4 , Figure 4 This is a flowchart illustrating an embodiment of the channel adaptive modulation method based on a lookup table according to this application. Figure 4 As shown, the channel adaptive modulation method based on lookup tables includes: S301: Receives modulated signals sent by the optical line terminal.

[0047] For example, an optical network unit (ONU) captures optical signals from an optical link via a coherent receiver. These signals are modulated using a geometrically shaped constellation diagram by the optical line terminal (OLT). The ONU converts the optical signals into electrical signals and performs synchronization processing to prepare data for subsequent demodulation. This step ensures the correct reception of physical layer signals, laying the foundation for recovering the original data.

[0048] S302: Obtain the geometrically shaped constellation diagram corresponding to the modulation signal.

[0049] For example, an optical network unit (ONU) reads a geometrically shaped constellation map matching the channel to which the modulated signal belongs from its local memory, or receives a geometrically shaped constellation map from an optical line terminal (OLT). This constellation map contains the specific coordinate distribution of the signal constellation points, determines the mapping rules required for demodulation, and ensures the consistency of the rules between the demodulation and modulation ends.

[0050] S303: Demodulate the modulated signal using the geometrically shaped constellation diagram to obtain the original data.

[0051] For example, based on the constellation point positions specified in the geometrically shaped constellation diagram, the received modulated signal is subjected to decision mapping to restore the signal points into a binary bit stream. This step utilizes the optimized constellation distribution characteristics, which can resist channel noise interference and accurately recover the original data transmitted by the optical line terminal.

[0052] This embodiment obtains the original data by acquiring a geometrically shaped constellation diagram that matches the modulated signal and demodulating the modulated signal, ensuring that the demodulation rules are strictly consistent with the modulation rules of the optical line terminal. This process accurately restores the signal constellation distribution optimized by geometric shaping and quantifies the degree of matching between the signal and the channel. Compared with traditional probabilistic shaping schemes, it eliminates the need for complex algorithms to be executed on the optical network unit side, reducing the processing difficulty at the terminal and effectively improving the transmission capacity and efficiency of passive optical networks while reducing bit errors.

[0053] Furthermore, in one embodiment, the method further includes: S401: Receive the training sequence sent by the optical line terminal.

[0054] The Optical Line Terminal (OLT) sends a Training Sequence (TS) to multiple Optical Network Units (ONUs), and the receivers on the ONU side receive the TS signals from the OLT.

[0055] S402: Estimate the signal-to-noise ratio of the channel based on the training sequence.

[0056] The Optical Network Unit (ONU) uses the TS signal to estimate the signal-to-noise ratio (SNR), and then feeds back the estimated SNR value to the OLT at the transmitting end.

[0057] S403: Feed back the signal-to-noise ratio to the optical line terminal so that the optical line terminal can establish or update its stored lookup table based on the signal-to-noise ratio.

[0058] Thirdly, embodiments of this application also provide a channel adaptive modulation device based on a lookup table, applied to an optical line terminal (OLT).

[0059] In one embodiment, reference is made to Figure 5 , Figure 5 This is a functional block diagram of an embodiment of the channel adaptive modulation device based on a lookup table according to this application. Figure 5 As shown, the channel adaptive modulation device based on a lookup table includes: A channel confirmation module is used to determine the optical network unit and the channel corresponding to the optical network unit. The first constellation diagram acquisition module is used to obtain the corresponding geometrically shaped constellation diagram by querying a pre-stored lookup table based on the optical network unit and the channel. A signal modulation module is used to modulate the original data using the geometrically shaped constellation diagram to obtain a modulated signal; A signal transmission module is used to transmit the modulated signal to the optical network unit.

[0060] Furthermore, in one embodiment, the channel adaptive modulation device based on the lookup table further includes a lookup table construction module, used for: obtaining the signal-to-noise ratio of the channel of the optical network unit; selecting the modulation order according to the signal-to-noise ratio; performing geometrically shaped constellation design using gradient calculation based on generalized mutual information combined with a trust region algorithm to obtain a geometrically shaped constellation diagram; and constructing a lookup table according to the geometrically shaped constellation diagram, the corresponding channel, and the optical network unit.

[0061] Furthermore, in one embodiment, the lookup table construction module obtains the signal-to-noise ratio (SNR) of the channel of the optical network unit by: sending a training sequence to the optical network unit; and receiving the SNR fed back by the optical network unit, wherein the SNR is estimated by the optical network unit based on the received training sequence.

[0062] The functions of each module in the above-mentioned lookup table-based channel adaptive modulation device correspond to the steps in the above-mentioned lookup table-based channel adaptive modulation method embodiment, and their functions and implementation processes will not be described in detail here.

[0063] Fourthly, embodiments of this application also provide a channel adaptive modulation device based on a lookup table, applied to an optical network unit (ONU).

[0064] In one embodiment, reference is made to Figure 6 , Figure 6This is a functional block diagram of an embodiment of the channel adaptive modulation device based on a lookup table according to this application. Figure 6 As shown, the channel adaptive modulation device based on a lookup table includes: A signal receiving module, which is used to receive modulated signals sent by the optical line terminal; The second constellation diagram acquisition module is used to acquire the geometrically shaped constellation diagram corresponding to the modulation signal; A signal demodulation module is used to demodulate the modulated signal using the geometrically shaped constellation diagram to obtain the original data.

[0065] Furthermore, in one embodiment, the channel adaptive modulation apparatus based on the lookup table further includes a signal-to-noise ratio (SNR) estimation module, which is used to receive a training sequence sent by the optical line terminal; estimate the SNR of the channel based on the training sequence; and feed back the SNR to the optical line terminal so that the optical line terminal can establish or update its stored lookup table based on the SNR.

[0066] Furthermore, in one embodiment, the second constellation map acquisition module acquires the geometrically shaped constellation map corresponding to the modulation signal, including: reading a pre-configured geometrically shaped constellation map from a local memory, or receiving a geometrically shaped constellation map sent by the optical line terminal.

[0067] Fifthly, embodiments of this application provide a channel adaptive modulation device based on a lookup table. The channel adaptive modulation device based on a lookup table can be a device with data processing functions, such as an OLT or ONU.

[0068] Reference Figure 7 , Figure 7 This is a schematic diagram of the hardware structure of a lookup table-based channel adaptive modulation device involved in an embodiment of this application. In this embodiment, the lookup table-based channel adaptive modulation device may include a processor, a memory, a communication interface, and a communication bus.

[0069] The communication bus can be of any type and is used to interconnect the processor, memory, and communication interface.

[0070] Communication interfaces include input / output (I / O) interfaces, physical interfaces, and logical interfaces used for interconnecting devices within the lookup table-based channel adaptive modulation (DAM) device, as well as interfaces used for interconnecting the DAM device with other devices (such as other computing devices or user equipment). Physical interfaces can be Ethernet interfaces, fiber optic interfaces, ATM interfaces, etc.; user equipment can be displays, keyboards, etc.

[0071] Memory can be various types of storage media, such as random access memory (RAM), read-only memory (ROM), non-volatile RAM (NVRAM), flash memory, optical storage, hard disk, programmable ROM (PROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), etc.

[0072] The processor can be a general-purpose processor, which can call a lookup table-based channel adaptive modulation program stored in memory and execute the lookup table-based channel adaptive modulation method provided in the embodiments of this application. For example, the general-purpose processor can be a central processing unit (CPU). The method executed when the lookup table-based channel adaptive modulation program is called can be referred to in the various embodiments of the lookup table-based channel adaptive modulation method of this application, and will not be repeated here.

[0073] Those skilled in the art will understand that Figure 7 The hardware structure shown does not constitute a limitation of this application and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0074] Sixthly, embodiments of this application also provide a computer-readable storage medium.

[0075] The present application stores a lookup table-based channel adaptive modulation program on a computer-readable storage medium, wherein when the lookup table-based channel adaptive modulation program is executed by a processor, it implements the steps of the lookup table-based channel adaptive modulation method as described above.

[0076] The method implemented when the lookup table-based channel adaptive modulation program is executed can be referred to in various embodiments of the lookup table-based channel adaptive modulation method of this application, and will not be repeated here.

[0077] It should be noted that the sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0078] The terms "comprising" and "having," and any variations thereof, in the specification, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such process, method, product, or apparatus. The terms "first," "second," and "third," etc., are used to distinguish different objects, etc., and do not indicate a sequence, nor do they limit "first," "second," and "third" to different types.

[0079] In the description of the embodiments of this application, terms such as "exemplary," "for example," or "for instance" are used to indicate examples, illustrations, or explanations. Any embodiment or design described as "exemplary," "for example," or "for instance" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of terms such as "exemplary," "for example," or "for instance" is intended to present the relevant concepts in a concrete manner.

[0080] In the description of the embodiments of this application, unless otherwise stated, " / " means "or". For example, A / B can mean A or B. The "and / or" in the text is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in the description of the embodiments of this application, "multiple" means two or more.

[0081] In some processes described in the embodiments of this application, multiple operations or steps are included in a specific order. However, it should be understood that these operations or steps may not be executed in the order they appear in the embodiments of this application, or they may be executed in parallel. The sequence number of the operation is only used to distinguish different operations, and the sequence number itself does not represent any execution order. In addition, these processes may include more or fewer operations, and these operations or steps may be executed sequentially or in parallel, and these operations or steps may be combined.

[0082] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above, and includes several instructions to cause a terminal device to execute the methods described in the various embodiments of this application.

[0083] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A channel adaptive modulation method based on lookup tables, applied to an optical line terminal (OLT), characterized in that, include: Determine the optical network unit and the channel corresponding to the optical network unit; Based on the optical network unit and the pre-stored lookup table for the channel query, the corresponding geometrically shaped constellation diagram is obtained; The original data is modulated using the geometrically shaped constellation diagram to obtain a modulated signal; The modulated signal is sent to the optical network unit.

2. The channel adaptive modulation method based on lookup table as described in claim 1, characterized in that, The lookup table is established through the following steps: Obtain the signal-to-noise ratio of the channel of the optical network unit; Select the modulation order based on the signal-to-noise ratio; A geometrically shaped constellation design is performed using gradient calculation based on generalized mutual information combined with a trust region algorithm, resulting in a geometrically shaped constellation diagram. A lookup table is constructed based on the geometrically shaped constellation diagram, the corresponding channels, and the optical network units.

3. The channel adaptive modulation method based on lookup table as described in claim 2, characterized in that, The acquisition of the signal-to-noise ratio of the channel of the optical network unit includes: Send training sequences to the optical network unit; The signal-to-noise ratio (SNR) fed back by the optical network unit is obtained by the optical network unit based on the received training sequence.

4. A channel adaptive modulation method based on a lookup table, applied to an optical network unit (ONU), characterized in that, include: Receive modulated signals sent by the optical line terminal; Obtain the geometrically shaped constellation diagram corresponding to the modulation signal; The modulated signal is demodulated using the geometrically shaped constellation diagram to obtain the original data.

5. The channel adaptive modulation method based on lookup table as described in claim 4, characterized in that, The method further includes: Receive the training sequence sent by the optical line terminal; Estimate the signal-to-noise ratio of the channel based on the training sequence; The signal-to-noise ratio is fed back to the optical line terminal so that the optical line terminal can build or update its stored lookup table based on the signal-to-noise ratio.

6. The channel adaptive modulation method based on lookup table as described in claim 4, characterized in that, The step of obtaining the geometrically shaped constellation diagram corresponding to the modulation signal includes: Read a pre-configured geometric constellation diagram from local memory, or receive a geometric constellation diagram sent by the optical line terminal.

7. A channel adaptive modulation device based on a lookup table, applied to an optical line terminal (OLT), characterized in that, include: A channel confirmation module is used to determine the optical network unit and the channel corresponding to the optical network unit. The first constellation diagram acquisition module is used to obtain the corresponding geometrically shaped constellation diagram by querying a pre-stored lookup table based on the optical network unit and the channel. A signal modulation module is used to modulate the original data using the geometrically shaped constellation diagram to obtain a modulated signal; A signal transmission module is used to transmit the modulated signal to the optical network unit.

8. A channel adaptive modulation device based on a lookup table, applied to an optical network unit (ONU), characterized in that, include: A signal receiving module, which is used to receive modulated signals sent by the optical line terminal; The second constellation diagram acquisition module is used to acquire the geometrically shaped constellation diagram corresponding to the modulation signal; A signal demodulation module is used to demodulate the modulated signal using the geometrically shaped constellation diagram to obtain the original data.

9. A channel adaptive modulation device based on a lookup table, characterized in that, The method includes a processor, a memory, and a lookup table-based channel adaptive modulation program stored in the memory and executable by the processor, wherein when the lookup table-based channel adaptive modulation program is executed by the processor, it implements the lookup table-based channel adaptive modulation method as described in any one of claims 1 to 3, or implements the lookup table-based channel adaptive modulation method as described in any one of claims 4 to 6.

10. A computer-readable storage medium, characterized in that, It stores a lookup table-based channel adaptive modulation program, wherein when the lookup table-based channel adaptive modulation program is executed by the processor, it implements the lookup table-based channel adaptive modulation method as described in any one of claims 1 to 3, or implements the lookup table-based channel adaptive modulation method as described in any one of claims 4 to 6.

Images