Training sequence sending method, training sequence receiving method, electronic device, and computer program product

Abstract

Embodiments of the present disclosure provide a training sequence sending method, a training sequence receiving method, an electronic device, and a computer program product. An optical line terminal (OLT) sends a training sequence to an optical network unit (ONU), wherein the training sequence is carried at a specified position of a superframe.

Description

Training sequence transmission and reception method, electronic device, and computer program product

[0001] Cross-reference to related disclosures

[0002] The present disclosure is based on Chinese Patent Publication 2024112368056 entitled "Training sequence transmission and reception method, electronic device, and computer program product" filed on September 4, 2024, and claiming priority to the patent publication, the disclosure of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0003] Embodiments of the present disclosure relate to the field of communications, and in particular, to a training sequence transmission and reception method, an electronic device, and a computer program product. BACKGROUND

[0004] A Passive Optical Network (PON) system is composed of an Optical Line Terminal (OLT) connecting multiple Optical Network Units (ONUs) through an Optical Distribution Network (ODN). In an ITU-T PON system, in the downstream direction, the OLT continuously transmits a superframe to the ONU. Currently, PON systems generally use Non-Return-to-Zero (NRZ) encoding to transmit 0 or 1 signals on an optical line. In order to prevent long continuous 0 signals or continuous 1 signals from appearing on the optical line, the transmitting side generally scrambles the transmitted signals so that the length of the continuous 0 signals or continuous 1 signals is within a certain range.

[0005] In an ITU-T 50G-PON system, in order to accelerate the equalization convergence of the ONU receiving in the downstream direction, the OLT needs to transmit a specific training sequence, and the ONU performs equalization training according to the training sequence and its reception, so as to accelerate the equalization convergence. Scrambling changes the sequence of 0 and 1 signals transmitted on the line, which can cause the training sequence with a fixed code type to be unable to be transmitted, and thus the training sequence cannot be transmitted in the current PON system. SUMMARY

[0006] Embodiments of the present disclosure provide a training sequence transmission and reception method, an electronic device, and a computer program product.

[0007] According to one embodiment of the present disclosure, a training sequence transmission method is provided, comprising: an Optical Line Terminal (OLT) transmitting a training sequence to an Optical Network Unit (ONU), the training sequence being carried in a specified position of a superframe.

[0008] According to another embodiment of the present disclosure, a training sequence receiving method is provided, comprising: an optical network unit (ONU) receiving training from a training sequence from an optical line terminal (OLT), the training sequence being carried in a designated position of a superframe.

[0009] According to yet another embodiment of the present disclosure, an electronic device is also provided, comprising a memory and a processor, the memory having stored therein a computer program, the processor being configured to execute the computer program to perform the steps of any of the method embodiments described above.

[0010] According to yet another embodiment of the present disclosure, a computer program product is also provided, comprising a computer program which, when executed by a processor, implements the steps of any of the method embodiments described above. BRIEF DESCRIPTION OF DRAWINGS

[0011] FIG. 1 is a schematic diagram of a scrambling code principle in the related art;

[0012] FIG. 2 is a schematic diagram of the structure of a downlink superframe in the related art;

[0013] FIG. 3 is a schematic diagram of the composition of a PSBd in the related art;

[0014] FIG. 4 is a hardware structure block diagram of a computer terminal of a training sequence sending method according to an embodiment of the present disclosure;

[0015] FIG. 5 is a flowchart of a training sequence sending method according to an embodiment of the present disclosure;

[0016] FIG. 6 is a flowchart of a training sequence receiving method according to an embodiment of the present disclosure;

[0017] FIG. 7 is an example diagram of the definition of a dBWmap according to an embodiment of the present disclosure;

[0018] FIG. 8 is an example diagram of an XGEM payload according to an embodiment of the present disclosure;

[0019] FIG. 9 is a schematic diagram of a training sequence sending and receiving principle according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0020] Embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0021] It should be noted that the terms "first", "second", etc. in the specification and claims of the present disclosure and the above-described accompanying drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or sequence.

[0022] FIG. 1 is a schematic diagram of a scrambling code principle in the related art, as shown in FIG. 1, ITU-T G.9804.2 adopts a polynomial x 58 +x39 +1 scrambling, the scrambling process is shown in the following figure, the initial 58 registers are composed of 7 1s and P1-P51, wherein P1-P51 are the superframe numbers carried by the current superframe, P51 is the highest bit of the superframe number, and P1 is the lowest bit of the superframe number.

[0023] Figure 2 is a schematic diagram of the structure of a downlink superframe in the related art. As shown in Figure 2, a downlink physical frame is composed of a downstream physical synchronization block (PSBd) and a physical frame payload. The PSBd is not scrambled, and the physical frame payload is scrambled. The scrambling starts from the first bit after the PSBd, and the next superframe starts the scrambling again.

[0024] Figure 3 is a schematic diagram of the composition of the PSBd in the related art. As shown in Figure 3, the PSBd is composed of a physical synchronization (PSync), a superframe count (SFC), and an operation control (OC). The SFC and the OC are exclusive-ORed with 0x0F0F0F0F 0F0F0F0F.

[0025] The method embodiments provided in the embodiments of the present disclosure can be executed in a mobile terminal, a computer terminal, or a similar computing device. Taking the case of running on a computer terminal, Figure 4 is a hardware structure block diagram of a computer terminal of a training sequence sending method according to an embodiment of the present disclosure. As shown in Figure 4, the computer terminal can include one or more (only one is shown in Figure 4) processors 402 (the processor 402 can include but is not limited to a processing device such as a microprocessor MCU or a programmable logic device FPGA) and a memory 404 configured to store data. The computer terminal can further include a transmission device 406 configured to have a communication function and an input and output device 408. Those skilled in the art can understand that the structure shown in Figure 4 is only schematic, and does not limit the structure of the computer terminal. For example, the computer terminal can include more or fewer components than those shown in Figure 4, or have a different configuration from that shown in Figure 4.

[0026] The memory 404 can be configured to store computer programs, for example, software programs of application software and modules, such as a computer program corresponding to the training sequence sending method in the embodiments of the present disclosure. The processor 402 can perform various functional applications and data processing, that is, implement the above method, by running the computer programs stored in the memory 404. The memory 404 can include a high-speed random access memory, and further include a nonvolatile memory, for example, one or more magnetic storage devices, flash memories, or other nonvolatile solid-state memories. In some examples, the memory 404 can further include memories located remotely relative to the processor 402, and the remote memories can be connected to the mobile terminal through a network. Examples of the network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and a combination thereof.

[0027] The transmission device 406 is configured to receive or send data via a network. The specific examples of the network can include a wireless network provided by a communication provider of a computer terminal. In one example, the transmission device 406 includes a network adapter (Network Interface Controller, NIC), which can be connected to other network devices through a base station so as to communicate with the Internet. In one example, the transmission device 406 can be a radio frequency (Radio Frequency, RF) module, which is configured to communicate with the Internet in a wireless manner.

[0028] The embodiments of the present disclosure provide a training sequence sending method, and FIG. 5 is a flowchart of the training sequence sending method according to the embodiments of the present disclosure. As shown in FIG. 5, the flow includes the following steps:

[0029] In step S502, the OLT sends a training sequence to the ONU, and the training sequence is carried in a designated position of a superframe.

[0030] In one example embodiment, the training sequence is carried in the designated position of the superframe, including: the OLT removes the scrambling code in the designated position of the superframe.

[0031] In the embodiments of the present disclosure, the designated position includes at least one of the following: a middle position of the superframe; a tail position of the superframe; a default position.

[0032] In the embodiments of the present disclosure, the specified position can be a position determined by the OLT and the ONU, such as a middle position of a superframe, a tail position of a superframe, or a default position agreed in advance, and the de-scrambling and the recovery of the scrambling code can be performed at the specified position of the superframe. The de-scrambling time, the recovery time of the scrambling code, and the initial value of the scrambling code shift register can be agreed between the OLT and the ONU. When to start the de-scrambling and how long to last can also be determined between the OLT and the ONU, mainly between the OLT and the ONU that has completed the training and entered the normal work. The ONU that has not completed the training needs to search for the low-speed information (i.e., the low-speed training sequence) of the de-scrambling part to obtain the start time of the training sequence.

[0033] In an example embodiment, the method further includes: the OLT sending first indication information to the ONU, the first indication information being used to indicate the ONU that has completed the training to identify at least one of the following: position information of the de-scrambling; position information of the recovery of the scrambling code; information of the training sequence.

[0034] In the embodiments of the present disclosure, the de-scrambling and the recovery of the scrambling code are performed in the middle or the tail of the superframe, and the OLT needs to give an indication, i.e., the first indication information, so that the ONU can identify the position of the de-scrambling and the recovery of the scrambling code, and the construction of the training sequence in the de-scrambling part.

[0035] In an example embodiment, the message type carrying the first indication information includes at least one of the following: a Physical Layer Operations, Administration, and Maintenance (PLOAM) message; and a Downstream Bandwidth map (dBWmap) message.

[0036] In an example embodiment, the PLOAM message carries superframe number (SFC) information, and the SFC information is used to indicate the start SFC number of the de-scrambling.

[0037] In the embodiments of the present disclosure, the PLOAM message is a slow processing message, needs to carry the SFC, indicates from which SFC to start the de-scrambling, and also includes the number of superframes for which the de-scrambling lasts. The start time and the end time of the de-scrambling in the superframe are also included. Of course, in the case of the de-scrambling in the tail of the superframe, the end time of the de-scrambling can not be carried.

[0038] In an example embodiment, the training sequence is carried in the specified position of the superframe, including: the OLT encapsulating the training sequence and related information in the specified position of the superframe by using an XGEM frame, and the XGEM frame carrying a specified XGEM port number Port-ID.

[0039] In the embodiments of the present disclosure, the OLT encapsulates at least one training sequence into an XGEM frame in a super frame.

[0040] In an embodiment, the training sequence can also be sent in multiple segments, for example, the training sequence can be a 100kbits PRBS, which can be sent at one time, so the total number of segments is 1 and the current segment number is 0, or the training sequence can be sent four times, so the total number of segments is 4 and the current segment number is 0-3.

[0041] In an exemplary embodiment, the training sequence is carried in a designated position of a super frame, including: the payload of the XGEM frame includes low-speed training sequence information and high-speed training sequence, the frame header of the XGEM frame contains the start position of the high-speed training sequence, and if the training sequence is sent in multiple segments, the number of the current training sequence segment being sent can also be contained in the XGEM frame header. In an embodiment, the low-speed training sequence information of the payload of the XGEM frame can include: a preamble, a synchronization header, a current segment number, a total number of segments, a remaining number of times of sending, a length of the training sequence, and low-speed training sequence information. If the training sequence is not segmented, the XGEM frame header and the payload of the XGEM frame can not contain the current number, the total number of segments, and the like.

[0042] In an exemplary embodiment, the low-speed training sequence includes at least one of: a low-speed preamble; a low-speed synchronization header; a current segment number of the training sequence; a total number of segments of the training sequence; a remaining number of times of sending of the training sequence; a length of the training sequence; and the training sequence.

[0043] In an exemplary embodiment, the OLT sends the training sequence to the ONU, including: the OLT sends the training sequence to the ONU according to a preset period; or the OLT sends the training sequence to the ONU according to a sending instruction.

[0044] In an exemplary embodiment, the method further includes: in a case where the ONU completes equalization training and is activated, the OLT restores scrambling to the designated position of the super frame.

[0045] Through the embodiments of the present disclosure, a training sequence sending method is provided, in which an optical line terminal (OLT) sends a training sequence to an optical network unit (ONU), and the training sequence is carried in a designated position of a super frame. The problem that a training sequence cannot be sent in a PON system in the related art is solved, and the effect of sending a training sequence in a PON system is achieved.

[0046] The embodiments of the present disclosure provide a training sequence receiving method, and FIG. 6 is a flowchart of the training sequence receiving method according to an embodiment of the present disclosure. As shown in FIG. 6, the flowchart includes the following steps:

[0047] In step S602, the ONU receives training by using the training sequence from the OLT, and the training sequence is carried in a designated position of a super frame.

[0048] In the embodiments of the present disclosure, the specified position can be a position determined by the OLT and the ONU, and in an embodiment, the OLT and the ONU determine the position through the first indication information. In an embodiment, the indicated position can also be a pre-agreed default position. In the embodiments of the present disclosure, the descrambling and the rescrarnbling at the default position of the superframe are agreed between the OLT and the ONU, and the descrambling time and the rescrarnbling time, the initial value of the scrambling shift register at the rescrarnbling time, etc. can also be agreed between the OLT and the ONU. When to start the descrambling and how long to continue can also be determined between the OLT and the ONU, mainly between the OLT and the ONU that has completed the training and entered the normal work. The ONU that has not completed the training needs to search for the low-speed information (i.e., the low-speed training sequence) of the descrambling part to obtain the start time of the training sequence.

[0049] In an example embodiment, the ONU that has completed the training receives the first indication information from the OLT, and the first indication information is used to indicate the ONU that has completed the training to identify at least one of the following: the position information of the descrambling; the position information of the rescrarnbling; the ONU that has completed the training stops descrambling at the position of the descrambling or descrambles at the position of the rescrarnbling according to the first indication information.

[0050] In the embodiments of the present disclosure, the descrambling and the rescrarnbling are performed in the middle or the tail of the superframe, and the OLT needs to give an indication, i.e., the first indication information, so that the ONU can identify the position of the descrambling and the rescrarnbling, and the construction of the training sequence in the descrambling part.

[0051] In an example embodiment, the ONU obtains the first indication information by analyzing the message type of at least one of the following: the PLOAM message; and the downlink bandwidth mapping (dBWmap) message.

[0052] In an example embodiment, the ONU obtains the superframe number (SFC) information from the PLOAM message, and stops descrambling at the specified position of the superframe corresponding to the SFC information.

[0053] In the embodiments of the present disclosure, the PLOAM message is a slow processing message, needs to carry the SFC, indicates from which SFC to start the descrambling, and also indicates the number of superframes for which the descrambling continues. The start time and the end time of the descrambling in the superframe are also included. Of course, in the case of the descrambling in the tail of the superframe, the end time of the descrambling can not be carried.

[0054] In one example embodiment, the ONU receives training from the training sequence from the OLT, including: the trained ONU parses the XGEM frame carrying the designated XGEM Port-ID to obtain the start position of the training sequence, and updates the training according to the training sequence at the start position, wherein the training sequence is the training sequence obtained and saved before the update training.

[0055] In one example embodiment, the trained ONU determines the start position of the training sequence according to the frame header of the XGEM frame.

[0056] In one example embodiment, the ONU receives training from the training sequence from the OLT, including: the untrained ONU obtains downlink clock synchronization according to the low-speed preamble of the low-speed training sequence, searches for the low-speed synchronization header based on the downlink clock synchronization, and parses to obtain at least one of the following information of the training sequence: the current segment number of the training sequence; the total segment number of the training sequence; the remaining transmission number of the training sequence, the length of the training sequence; the low-speed training sequence. The untrained ONU obtains the content and start position of the training sequence based on the low-speed training sequence, saves the content of the training sequence, and trains according to the high-speed training sequence.

[0057] In the embodiments of the present disclosure, for the ONU that has completed training and activation, the position information of the de-scrambling is obtained according to the first indication information, the specified area part is not de-scrambled, and the de-scrambling shift register initial value is set and the de-scrambling is restored after the specified area. If necessary, the position of the high-speed training sequence can be obtained according to the XGEM frame header in front of the de-scrambling area, and the update training is performed according to the training sequence recorded in the power-on state or agreed.

[0058] In the embodiments of the present disclosure, the ONU is in a low-speed working mode when powered on, and attempts to search for low-speed information (i.e., low-speed training sequence), obtains downlink clock synchronization according to the low-speed preamble, and further searches for a synchronization header. After the synchronization header is searched and confirmed, for example, after the synchronization header is detected in a plurality of consecutive superframes, the current segment number and the total segment number and their regularity are confirmed, in order to receive the correct training sequence after subsequent conversion to a high-speed working mode. The remaining transmission number is confirmed, and if the remaining number is sufficient, the high-speed working mode can be converted. The training sequence length and the low-speed training sequence are confirmed. The low-speed training sequence is a bit sequence, which can be a complete PRBS code sequence or a segment thereof, and the high-speed training sequence is the same bit sequence. The low-speed training sequence is transmitted at a low speed, and the high-speed training sequence is transmitted at a high speed.

[0059] Those skilled in the art can clearly understand that the method according to the above-mentioned embodiments can be realized by means of software on a general hardware platform, and of course, can also be realized by hardware, but in many cases, the former is a better implementation. Based on such understanding, the technical solutions of the present disclosure can be embodied in the form of a software product, which is stored in a storage medium (such as a ROM / RAM, a magnetic disk, or an optical disk) and includes a plurality of instructions for causing a terminal device (which can be a mobile phone, a computer, a server, or a network device) to perform the methods described in the various embodiments of the present disclosure.

[0060] In the embodiments, a training sequence sending device and a training sequence receiving device are also provided, which are configured to implement the above-mentioned embodiments and preferred embodiments, and will not be described again. As used below, the term "module" can be a combination of software and / or hardware that implements a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, implementation of hardware, or a combination of software and hardware, is also possible and contemplated.

[0061] The training sequence sending device provided by the embodiments of the present disclosure can be arranged in an optical line terminal (OLT) and includes a first sending module configured to send a training sequence to an optical network unit (ONU), the training sequence being carried in a designated position of a superframe.

[0062] The training sequence receiving device provided by the embodiments of the present disclosure can be arranged in an optical network unit (ONU) and includes a receiving module configured to receive training from a training sequence from an OLT, the training sequence being carried in a designated position of a superframe.

[0063] In the embodiments of the present disclosure, the training sequence sending device and the training sequence receiving device described above can also include different modules, and the naming and function division of the modules can also be selected in different ways according to actual conditions, which are not specifically limited here.

[0064] It should be noted that the above-mentioned modules can be realized by software or hardware. For the latter, the following implementation manners can be used, but are not limited thereto: the above-mentioned modules are located in the same processor; or the above-mentioned modules are located in different processors in any combination.

[0065] The embodiments of the present disclosure also provide a computer-readable storage medium, which stores a computer program, wherein the computer program is configured to execute the steps in any of the above-mentioned method embodiments when running.

[0066] In an example embodiment, the computer readable storage medium described above can include, but is not limited to, a U disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a mobile hard disk, a magnetic disk or an optical disk, and various media that can store computer programs.

[0067] Embodiments of the present disclosure also provide an electronic device including a memory and a processor, the memory storing a computer program, and the processor being configured to execute the computer program to perform the steps in any of the method embodiments described above.

[0068] In an example embodiment, the electronic device described above can further include a transmission device connected to the processor and an input / output device connected to the processor.

[0069] Embodiments of the present disclosure also provide a computer program product including a computer program, the computer program being executed by a processor to implement the steps in any of the method embodiments described above.

[0070] In an example embodiment, the computer program product described above includes a non-volatile computer readable storage medium storing a computer program, the computer program being executed by a processor to implement the steps in the methods described in various embodiments of the present disclosure.

[0071] The specific examples in the present embodiment can refer to the examples described in the above embodiments and example implementations, which will not be described herein again.

[0072] Obviously, those skilled in the art should understand that the modules or steps of the present disclosure described above can be realized by general computing devices, which can be concentrated on a single computing device or distributed on a network composed of multiple computing devices, and can be realized by program codes executable by computing devices, so that they can be stored in storage devices and executed by computing devices, and in some cases, the steps shown or described can be executed in different orders, or they can be manufactured into individual integrated circuit modules, or multiple modules or steps can be manufactured into a single integrated circuit module. Thus, the present disclosure is not limited to any specific combination of hardware and software.

[0073] In order to enable those skilled in the art to better understand the technical solutions of the present disclosure, different embodiments are described below.

[0074] Embodiment One

[0075] In the embodiments of the present disclosure, in order not to break the starting rule of the scrambling code, the scrambling code can be removed at the end of the super frame and then recovered at the beginning of each super frame; of course, the scrambling code can also be removed and then recovered at the middle position of the super frame, and when the scrambling code is recovered at the middle position of the super frame, the initial value of the scrambling code register mainly needs to be considered, the register value when the scrambling code is stopped can be used as the initial value, or the default value can be used to update the initial value.

[0076] In the embodiments of the present disclosure, the scrambling code is removed and then recovered at the middle or end of the super frame, and the OLT needs to give an indication, that is, first indication information, so that the ONU can identify the position of the removed and recovered scrambling code and the construction of the training sequence in the removed scrambling code part. The indication manner of the first indication information can be various: PLOAM message, dBWmap.

[0077] In the embodiments of the present disclosure, the PLOAM message is defined, and Table 1 is an example table of the definition of the PLOAM message. As shown in Table 1, the PLOAM message is a slow processing message, needs to carry the SFC, indicates from which SFC the scrambling code is removed, and further includes the number of super frames in which the scrambling code is removed. Further, the start time and the end time of the scrambling code removal in the super frame are included, and of course, the end time of the scrambling code removal can not be carried in the case of the scrambling code removal at the end of the super frame.

[0078] Table 1 is an example table of the definition of the PLOAM message.

[0079] FIG. 7 is an example diagram of the definition of the dBWmap in the embodiments of the present disclosure. As shown in FIG. 7, the dBWmap is defined, and the dBWmap is a fast processing message and can be used only to indicate the scrambling code removal of the current super frame. The format of the dBWmap is as follows: when Flags is 0000b, it indicates the scrambling code removal (since the dBWmap can be used for many functions, the downlink scrambling code removal is one of them), the meaning of GroupID is determined by Flags, and here it indicates the group of the scrambling code removal. If there are multiple groups, the groups can be numbered, GroupID = number, StartTime indicates the start time of the scrambling code removal, GrantSize indicates the duration of the scrambling code removal, Pattern indicates the pattern used when the scrambling code is recovered, 0: default initial value, that is, 7 ones and P1-P51 are composed, and 1: register value when the scrambling code is removed in the current super frame.

[0080] In the embodiments of the present disclosure, the descrambling and recovery of scrambling can also be performed at the default position of the superframe, and the descrambling time and recovery time of scrambling, the initial value of the scrambling shift register at the recovery time of scrambling, etc. can be agreed between the OLT and the ONU. When to start the descrambling and how long to continue can also be determined between the OLT and the ONU, mainly between the OLT and the ONU which has completed the training and entered the normal work. The ONU which has not completed the training needs to search the low-speed information (i.e. the low-speed training sequence) of the descrambling part to obtain the start time of the training sequence.

[0081] In the embodiments of the present disclosure, the descrambling part is used to carry the training sequence, and the format is as follows: XGEM encapsulation is adopted, and a specific XGEM Port-ID (for example, 0xFFFE) is carried in the frame header, which indicates that the XGEM frame carries the training sequence. The ONU which has completed the equalization training can ignore the XGEM frame, or can update the equalization training by means of the training sequence. The start position of the training sequence in the XGEM frame header is used to determine where the training sequence starts from the payload. The current number is used to obtain which part of the training sequence is sent by the OLT. Because the ONU which has completed the equalization training has obtained the training sequence and the number, the ONU can know which part of the training sequence is currently sent by the OLT from the number.

[0082] Fig. 8 is an example diagram of the XGEM payload in the embodiments of the present disclosure. As shown in Fig. 8, the XGEM payload part includes low-speed information and high-speed training sequence. The low-speed information includes a preamble, a synchronization header, a current segment number and a total segment number, a remaining transmission number, a training sequence length, and low-speed training sequence information. Taking 50G-PON as an example, the downlink high-speed mode is 49.7664 Gbps, and the low-speed mode is 12.4416 Gbps. The low-speed preamble can be 1856-7600 low-speed bits or other lengths, and the pattern can be a low-speed 0, 1 interlaced type or a corresponding PRBS type. The synchronization header can be 64 low-speed bits, and the pattern can be 0x B9D4 3E68 462B C197. The current segment number and the total segment number can each be 4 low-speed bits. A maximum of 16 segments can be transmitted, and the numbers are 0-15 (for example, the training sequence can be a 100kbits PRBS, which can be transmitted at a time, so that the total segment number is 1 and the current segment number is 0, or the training sequence can be transmitted four times, so that the total segment number is 4 and the current segment number is 0-3). The remaining transmission number can be 16 low-speed bits, and the maximum is 65535, which is reduced by one every 125μs, which is equivalent to that the training sequence can be continuously transmitted for 65535 times, and the duration is about 8 seconds. Of course, this field can be adjusted to be larger or smaller according to the needs. The training sequence length can be 24 low-speed bits, and the longest can represent 16M bits. The low-speed training sequence and the high-speed training sequence are the same in the bit sequence, and only the transmission rate is different. The training sequence can be a corresponding PRBS sequence.

[0083] In the embodiments of the present disclosure, the content of the de-scrambling part can be adjusted as required, for example, if the training sequence is not segmented, the fields of the current segment number and the total segment number can be cancelled; for another example, the training sequence can also be a default sequence, and the fields of the training sequence length and the low-speed training sequence can be cancelled. In particular, since the PSync at the front of the PSBd field is a fixed code type, 0xC5E51840 FD59BB49, which is not scrambled, can be used as the training sequence, and at this time, the high-speed training sequence, i.e., the PSync field, is de-scrambled at the end of the superframe. The XGEM frame payload de-scrambled at the end of the superframe can contain PSync. Of course, in order to increase the training effect, the PSync can be lengthened as required.

[0084] Embodiment Two

[0085] In the present embodiment, the process of sending and receiving the training sequence is introduced in detail.

[0086] FIG. 9 is a schematic diagram of the training sequence sending and receiving principle according to an embodiment of the present disclosure. As shown in FIG. 9, in the embodiments of the present disclosure, the OLT de-scrambles and sends the training sequence in the superframe as required. The training sequence can be de-scrambled and sent periodically, or can be de-scrambled and sent by network management, command line, etc. If the indication is performed by the PLOAM message, the Training_Stream PLOAM message is sent before the specified SFC arrives. If the indication is performed by the dBWmap, the dBWmap is sent at the head of the superframe in which the training sequence is required to be de-scrambled and sent. If the de-scrambling and sending of the training sequence are performed at the agreed fixed position, the agreed SFC can be started at the beginning of the superframe, and the training sequence can be de-scrambled and sent for the agreed superframe number.

[0087] In the embodiments of the present disclosure, when the ONU is in the power-on state, it is in the low-speed working mode and attempts to search for low-speed information (i.e., low-speed training sequence), obtains downlink clock synchronization according to the low-speed preamble, and further searches for a synchronization header. After the synchronization header is searched and confirmed, for example, after the synchronization header is detected in a plurality of consecutive superframes, the current segment number and the total number of segments and their regularity are confirmed, so as to receive the correct training sequence after the subsequent conversion to the high-speed working mode. The remaining number of times is confirmed, and if the remaining number of times is sufficient, the high-speed working mode can be converted. The training sequence length and the low-speed training sequence are confirmed. The low-speed training sequence is a bit sequence, which can be a complete PRBS code sequence or a segment thereof, and the high-speed training sequence is the same bit sequence. Of course, the low-speed training sequence is transmitted at the low speed, and the high-speed training sequence is transmitted at the high speed. For example, in a 50G-PON, the high-speed training sequence is transmitted at 49.7664 Gbps, and the low-speed training sequence is transmitted at 12.4416 Gbps. The low-speed rate is one fourth of the high-speed rate. After the training sequence transmission regularity, the remaining number of training sequence transmissions, and the training sequence are confirmed, the high-speed working mode is converted, and the high-speed training sequence is received at the high-speed training sequence position of the subsequent superframe and is subjected to equalization training until the equalization training is completed. After the equalization training is completed, the normal high-speed working mode is performed.

[0088] In the embodiments of the present disclosure, the ONU that has completed the training receives the training sequence from the OLT, and the ONU that has completed the training updates the training according to the training sequence. In an embodiment, the ONU that has completed the training removes the scrambling according to the first indication information, determines the start position of the training sequence according to the frame header of the XGEM, and updates the training according to the high-speed training sequence.

[0089] In the embodiments of the present disclosure, for the ONU that has completed the training and is activated, the position information of the removed scrambling is obtained according to the first indication information, the specified area is stopped from being descrambled, the descrambling shift register initial value is set and the descrambling is restored after the specified area. If necessary, the position of the high-speed training sequence can be obtained according to the XGEM frame header in front of the removed scrambling area, and the training is updated according to the training sequence recorded in the power-on state or agreed.

[0090] In the embodiments of the present disclosure, the specific equalization training scheme can be implemented in the adaptive equalization manner of the ONU receiving end. Taking the linear equalization algorithm as an example, in the adaptive module on the ONU side, the input data is the received high-speed training sequence, the parameters of the equalizer are adjusted through the commonly used weighting algorithms such as LMS or RLS, so that the output sequence is as close as possible to the low-speed training sequence. After multiple cycles, the equalization parameters can converge and stabilize.

[0091] In the embodiments of the present disclosure, it is pointed out that the OLT is always sent in high-speed mode, and when sending low-speed information, the low-speed signal is simulated by repeating the sending of 0 and 1 bits. For example, the high-speed mode is 49.7664 Gbps, and the low-speed mode is 12.4416 Gbps, then the OLT sends 4 continuous 0 signals to simulate a low-speed 0 signal, and sends 4 continuous 1 signals to simulate a low-speed 1 signal.

[0092] The training sequence sending and receiving method provided by the embodiments of the present disclosure is applicable to effects such as inter-symbol crosstalk caused by dispersion accumulation of different transmission links, linear impairment caused by insufficient bandwidth of an ONU receiver system, and symbol crosstalk equivalent effect caused by ONU sampling clock offset, but is not limited to the above.

[0093] In the embodiments of the present disclosure, the OLT sends a superframe in the downstream direction, sends a training sequence in the middle or tail of the superframe, and does not scramble the training sequence. Since the receiving side cannot normally receive before the training sequence, a low-speed preamble, a delimiter, a remaining sending number, and training sequence related information are sent before the training sequence. The low-speed 0 signal can be simulated by sending continuous 0 bits, or the low-speed 1 signal can be simulated by sending continuous 1 bits, and the scrambling is not disturbed, so that the ONU can identify the training sequence and its position in the low-speed mode, and locate and obtain the training sequence position, that is, the training sequence, in the high-speed mode.

[0094] The training sequence sending and receiving method in the high-speed passive optical network system provided by the embodiments of the present disclosure realizes flexible scrambling and descrambling, and sends the training sequence in the descrambling stage, so that the ONU can complete the downlink receiving equalization training in time according to the training sequence.

[0095] The above only describes the preferred embodiments of the present disclosure and is not used to limit the present disclosure. For those skilled in the art, the present disclosure can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. within the principles of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A training sequence sending method, comprising: sending, by an optical line terminal (OLT), a training sequence to an optical network unit (ONU), the training sequence being carried in a designated location of a super frame.

2. The method of claim 1, wherein, the training sequence being carried in the designated location of the super frame comprises: the OLT de-scrambling in the designated location of the super frame.

3. The method of claim 2, wherein, Further comprising: the OLT sending first indication information to the ONU, the first indication information being used to indicate that training has been completed, and the ONU identifying at least one of the following based on the first indication information: location information of de-scrambling; location information of resuming scrambling.

4. The method of claim 3, wherein, the message type carrying the first indication information comprises at least one of the following: a physical layer operation administration and maintenance (PLOAM) message; and a downlink bandwidth map (dBWmap) message.

5. The method of claim 4, wherein, the PLOAM message carries super frame number (SFC) information, and the SFC information is used to indicate a starting SFC number of de-scrambling.

6. The method of claim 1, wherein, the training sequence being carried in the designated location of the super frame comprises: the OLT encapsulating the training sequence and related information in an XGEM frame in the designated location of the super frame, and the XGEM frame carrying a designated XGEM port number (Port-ID).

7. The method of claim 6, wherein, the training sequence being carried in the designated location of the super frame comprises: a payload of the XGEM frame comprises low-speed training sequence information and high-speed training sequence, and a frame header of the XGEM frame contains a start position of the high-speed training sequence.

8. The method of claim 7, wherein, the low-speed training sequence information comprises at least one of the following: a low-speed preamble; a low-speed synchronization header; a current segment number of the training sequence; a total segment number of the training sequence; a remaining sending number of the training sequence; a length of the training sequence; and the training sequence.

9. The method of claim 1, wherein, the OLT sending the training sequence to the ONU comprises: the OLT sending the training sequence to the ONU according to a preset period; alternatively, the OLT sending the training sequence to the ONU according to a sending instruction.

10. The method of claim 2, wherein, Further comprising: in a case where the ONU completes equalization training and is activated, the OLT resumes scrambling in the designated location of the super frame. 11.A training sequence receiving method, comprising: receiving, by an optical network unit (ONU), training from a training sequence from an optical line terminal (OLT), the training sequence being carried in a designated location of a super frame.

12. The method of claim 11, wherein, Further comprising: the ONU receiving first indication information from the OLT, the first indication information being used to indicate that training has been completed, and the ONU identifying at least one of the following based on the first indication information: location information of de-scrambling; location information of resuming scrambling. the ONU stopping de-scrambling in a location of de-scrambling or performing de-scrambling in a location of resuming scrambling according to the first indication information.

13. The method of claim 12, wherein, the ONU obtaining the first indication information by analyzing at least one of the following message types: a physical layer operation administration and maintenance (PLOAM) message; and a downlink bandwidth map (dBWmap) message.

14. The method of claim 13, wherein, the ONU obtaining super frame number (SFC) information from the PLOAM message, and stopping de-scrambling in the designated location of the super frame corresponding to the SFC information.

15. The method of claim 11, wherein, the ONU receiving training from the training sequence from the OLT comprises: The trained ONU parses the XGEM frame carrying the specified XGEM Port-ID, obtains the start position of the training sequence, and updates the training according to the training sequence at the start position, wherein the training sequence is the training sequence obtained and saved before the update training.

16. The method of claim 15, wherein, The trained ONU determines the start position of the training sequence according to the frame header of the XGEM frame.

17. The method of claim 11, wherein, The ONU receives the training with the training sequence from the OLT, including: The untrained ONU obtains the downlink clock synchronization according to the low-speed preamble of the low-speed training sequence, searches for the low-speed synchronization header based on the downlink clock synchronization, and parses and obtains at least one of the following information of the training sequence: the current segment number of the training sequence; the total segment number of the training sequence; the remaining transmission number of the training sequence, the length of the training sequence; the low-speed training sequence; The untrained ONU obtains the content and start position of the training sequence based on the low-speed training sequence, saves the content of the training sequence, and trains according to the high-speed training sequence.

18. An electronic device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, wherein the processor implements the method of any one of claims 1 to 17 when executing the computer program.

19. A computer program product comprising a computer program, wherein the computer program implements the method of any one of claims 1 to 17 when executed by a processor.

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