Data transmission method, optical line terminal, optical network unit, readable medium

Abstract

The present disclosure provides an upstream data transmission method including: receiving an upstream optical signal; generating second upstream electrical signals in a plurality of lanes based on the upstream optical signal; lane-aligning the second upstream electrical signals in the plurality of lanes according to the upstream granularity, and restoring the signals after alignment to obtain a target upstream signal. The present disclosure further provides a downstream data transmission method including: receiving a downstream optical signal; generating second downstream electrical signals in a plurality of lanes based on the downstream optical signal; lane-aligning the second downstream electrical signals in the plurality of lanes according to the downstream granularity, and restoring the signals after alignment to obtain a target downstream signal. The present disclosure further provides an optical line terminal, an optical network unit, and a computer-readable medium.

Description

Technical Field

[0001] This application claims the priority of Chinese Patent Application CN202210614586.5, titled "Data Transmission Method, Optical Line Terminal, Optical Network Unit, Readable Medium", filed on May 30, 2022, and incorporates all of its content by reference into this application.

[0002] The present disclosure relates to the field of communication technologies, and particularly to data transmission methods, optical line terminals, optical network units, and computer-readable media.

Background Art

[0003] Passive Optical Network (PON) is a popular wired access technology currently under research. One Optical Line Terminal (OLT) and several Optical Network Units (ONUs) are connected by an Optical Distribution Network (ODN). The network configuration of PON is generally divided into two types: Point-to-Point (P2P) and Point-to-Multiple-Point (P2MP). The information access of PON is divided into two directions: downstream and upstream. Downstream, the OLT sends signals to the ONU, and upstream, the ONU sends signals to the OLT.

[0004] With the evolution of several generations of technologies, the current access rate of PON is evolving from 1G PON to 50G PON. However, with the improvement of the access rate of PON, the requirements for hardware are becoming increasingly high, and the difficulty of implementation is also increasing.

Summary of the Invention

Problems to be Solved by the Invention

[0005] Embodiments of the present disclosure provide a data transmission method, an optical line terminal, an optical network unit, and a computer-readable medium. **Means for Solving the Problem**

[0006] In a first aspect, embodiments of the present disclosure provide a data transmission method including: receiving an upstream optical signal; generating second upstream electrical signals in a plurality of lanes based on the upstream optical signal, where the second upstream electrical signals in the plurality of lanes respectively correspond to first upstream electrical signals in the plurality of lanes obtained by an upstream transmitting end cross-dividing an initial upstream signal according to an upstream granularity; and lane-aligning the second upstream electrical signals in the plurality of lanes according to the upstream granularity, and restoring the signals after alignment to obtain a target upstream signal.

[0007] In a second aspect, embodiments of the present disclosure provide a data transmission method including: cross-dividing an initial upstream signal according to an upstream granularity to obtain first upstream electrical signals in a plurality of lanes; generating one upstream optical signal based on the first upstream electrical signals in the plurality of lanes; and transmitting the upstream optical signal.

[0008] In a third aspect, embodiments of the present disclosure provide a data transmission method including: receiving a downstream optical signal; generating second downstream electrical signals in a plurality of lanes based on the downstream optical signal, where the second downstream electrical signals in the plurality of lanes respectively correspond to first downstream electrical signals in the plurality of lanes obtained by a downstream transmitting end cross-dividing an initial downstream signal according to a downstream granularity; and lane-aligning the second downstream electrical signals in the plurality of lanes according to the downstream granularity, and restoring the signals after alignment to obtain a target downstream signal.

[0009] In a fourth aspect, an embodiment of the present disclosure provides a data transmission method including: cross-dividing an initial downlink signal according to a downlink granularity to obtain first downlink electrical signals in a plurality of lanes; generating one downlink optical signal based on the first downlink electrical signals in the plurality of lanes; and transmitting the downlink optical signal.

[0010] In a fifth aspect, an embodiment of the present disclosure provides an optical line terminal including: one or more processors; and a memory storing one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors are caused to implement the data transmission method according to the first aspect and / or the data transmission method according to the fourth aspect of the embodiments of the present disclosure.

[0011] In a sixth aspect, an embodiment of the present disclosure provides an optical network unit including: one or more processors; and a memory storing one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors are caused to implement the data transmission method according to the second aspect and / or the data transmission method according to the third aspect of the embodiments of the present disclosure.

[0012] In a seventh aspect, an embodiment of the present disclosure provides a computer-readable medium storing a computer program, wherein when the program is executed by a processor, the processor is caused to implement the data transmission method according to the first aspect and / or the second aspect and / or the third aspect and / or the fourth aspect of the embodiments of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0013]

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Embodiments for Carrying Out the Invention

[0014] To enable those skilled in the art to better understand the technical solutions of the present disclosure, the data transmission method, optical line terminal, optical network unit, and computer-readable medium according to the present disclosure will be described in detail below in combination with the drawings.

[0015] Hereinafter, exemplary embodiments will be fully described with reference to the drawings. However, the disclosed embodiments may be embodied in different forms and should not be construed as limited to the embodiments described herein. Rather, these embodiments are provided to thoroughly and completely disclose the present disclosure and to enable those skilled in the art to fully understand the scope of the present disclosure.

[0016] It should be noted that the embodiments of the present disclosure and the features in the embodiments can be arbitrarily combined with each other as long as they do not conflict.

[0017] For example, the term "and / or" as used herein includes any combination and all combinations of one or more of the related listed items.

[0018] The terms used in this specification are for the purpose of describing specific embodiments only and are not intended to limit the present disclosure. For example, the singular forms "one" and "the" used in this specification are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprising" and "consisting of" used in this specification specify the presence of the described features, wholes, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components, and / or groups thereof.

[0019] Unless otherwise specifically limited, all terms used in this specification, including technical and scientific terms, have the same meaning as commonly understood by those skilled in the art. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology and the present disclosure, and it should also be understood that they should not be interpreted as having an ideal or overly formal meaning unless specifically limited as such in the present disclosure.

[0020] With the improvement of the access rate of PON, the requirements for hardware are becoming increasingly high. For example, in 50G PON, a 50G Non Return to Zero (NRZ) signal needs to perform electro-optical conversion at the transmitting end and opto-electrical conversion at the receiving end during the process of optical fiber transmission. Compared with the serializer / deserializer (SERDES) used for the transmission of 25G NRZ signals, the SERDES used for the transmission of 50G NRZ signals has high requirements for hardware devices and printed circuit boards, and is not yet technically mature enough, making it more difficult to realize 50G NRZ signal transmission. On the other hand, the related technology for realizing high-rate optical transmission by converting NRZ signals into 4-level Pulse Amplitude Modulation (PAM4) does not meet the requirements of ITU-T standards.

[0021] Based on this, referring to FIG. 1, an embodiment of the present disclosure provides a data transmission method including the following steps S11 to S13.

[0022] In step S11, an upstream optical signal is received.

[0023] In step S12, second upstream electrical signals in a plurality of lanes are generated based on the upstream optical signal. Here, the second upstream electrical signals in the plurality of lanes respectively correspond to the first upstream electrical signals in the plurality of lanes obtained by cross-dividing an initial upstream signal according to the upstream granularity at the upstream transmitting end.

[0024] In step S13, the second upstream electrical signals in the plurality of lanes are lane-aligned according to the upstream granularity, and after alignment, they are restored to obtain a target upstream signal.

[0025] The data transmission method according to the embodiment of the present disclosure is applied to the receiving end in the upstream direction. In the embodiment of the present disclosure, in the upstream direction, an optical network unit (ONU) is the transmitting end, and an optical line terminal (OLT) is the receiving end.

[0026] In the embodiment of the present disclosure, the upstream receiving end receives an optical signal transmitted from the upstream transmitting end. At the upstream transmitting end, after cross-dividing an initial upstream signal according to a preset upstream granularity to obtain first upstream electrical signals in a plurality of lanes, one upstream optical signal is generated based on the first upstream electrical signals in the plurality of lanes and transmitted to the upstream receiving end. The upstream receiving end generates second upstream electrical signals in the plurality of lanes based on the received upstream optical signal. Here, the plurality of second upstream electrical signals of the upstream receiving end and the plurality of first upstream electrical signals of the upstream transmitting end correspond one-to-one, that is, the number of lanes of the upstream transmitting end is the same as the number of lanes of the upstream receiving end, and the plurality of lanes of the upstream transmitting end and the plurality of lanes of the upstream receiving end correspond one-to-one. The number of lanes in the present disclosure is not particularly limited, and may be, for example, 2, 4, 8, etc.

[0027] In the embodiments of the present disclosure, the cross-division of the initial upstream signal by the upstream transmission end according to a preset upstream granularity refers to dividing the initial upstream signal into a plurality of data fragments according to the preset upstream granularity. Here, a data fragment consists of at least 1 bit (bit) that satisfies the preset upstream granularity among the initial upstream signals. Assuming that the upstream transmission end has X lanes, adjacent X data fragments in the initial upstream signal are respectively divided into X different lanes, and the bit stream composed of the data fragments divided into each lane becomes the first upstream electrical signal in each lane. For example, the upstream transmission end has X lanes, and the preset upstream granularity is N bit, that is, the initial upstream signal is divided into one data fragment every N bit. The bit stream obtained by combining the (iX)th bit and the subsequent N - 1 bits is used as the first upstream electrical signal in one lane, and the bit stream obtained by combining the (iX + 1)th bit and the subsequent N - 1 bits is used as the first upstream electrical signal in one lane, ……, the bit stream obtained by combining the (iX + X - 1)th bit and the subsequent N - 1 bits is used as the first upstream electrical signal in one lane. In this way, X first upstream electrical signals corresponding to X lanes are obtained, and i takes values in the order of 0, 1, 2, 3, ….

[0028] In some embodiments, the number of lanes at the upstream transmission end is 2. When cross-dividing the initial upstream signal according to a preset upstream granularity, the plurality of data fragments obtained by dividing the initial upstream signal can be divided into odd fragments and even fragments. The bit stream after combining the odd fragments is used as one first upstream electrical signal, and the bit stream after combining the even fragments is used as another first upstream electrical signal.

[0029] In the present disclosure, the preset granularity is not particularly limited. For example, the preset granularity may be 1 bit, 4 bit, or 8 bit.

[0030] In the present disclosure, the initial upstream signal is not particularly limited. For example, the initial upstream signal can be any one of an NRZ signal, a PAM4 signal, a scrambled bitstream, or an interleaved bitstream (Bitstream Scrambling / Bitstream Interleaving).

[0031] In an embodiment of the present disclosure, the upstream transmitting end cross-divides the initial upstream signal and serves to reduce the rate of the NRZ signal. That is, the rates of a plurality of first upstream electrical signals obtained by cross-dividing the initial upstream signal are smaller than the rate of the initial upstream signal. In some embodiments, the sum of the rates of the plurality of first upstream electrical signals is equal to the rate of the initial upstream signal. For example, if the initial upstream signal is a 50G NRZ signal, two 25G NRZ signals are obtained by cross-division, or if the initial upstream signal is a 100G NRZ signal, two 50G NRZ signals are obtained by cross-division, or if the initial upstream signal is a 100G NRZ signal, four 25G NRZ signals are obtained by cross-division.

[0032] In an embodiment of the present disclosure, the rates of a plurality of second upstream electrical signals generated based on the upstream optical signal received by the upstream transmitting end are the same as the rates of the plurality of first upstream electrical signals at the transmitting end. For example, when the upstream transmitting end generates two 25G NRZ signals, the upstream receiving end generates two 25G NRZ signals based on the upstream optical signal, and when the upstream transmitting end generates four 25G NRZ signals, the upstream receiving end generates four 25G NRZ signals based on the upstream optical signal. The upstream receiving end cross-restores the second upstream electrical signals in a plurality of lanes according to a preset granularity, that is, according to the rule by which the upstream transmitting end cross-divides the initial upstream signal, the plurality of second upstream electrical signals are restored to a target upstream signal. In some embodiments, the target upstream signal is the same as the initial upstream signal. In some embodiments, the target upstream signal is an approximation of the initial upstream signal.

[0033] Note that the rate of the target upstream signal obtained by the upstream transmission end through cross restoration is the same as the rate of the initial upstream signal, and the rate of the upstream optical signal transmitted between the transmission end and the reception end is the same as the rate of the initial upstream signal. Thus, high-rate optical transmission can be realized using low-rate hardware devices. For example, if the initial upstream signal is a 50G NRZ signal, it is cross-divided into two 25G NRZ signals at the transmission end and restored to a 50G NRZ signal at the reception end to obtain the target upstream signal. Here, the transmission end and the reception end can process the two 25G NRZ signals based on 25G hardware devices, and by transmitting with a 50G optical signal, 50G optical transmission based on 25G hardware devices can be realized.

[0034] According to the data transmission method according to the embodiments of the present disclosure, in the upstream direction, the transmission end cross-divides a high-rate initial signal into a plurality of low-rate electrical signals and transmits them to the reception end by a high-rate optical signal, and the reception end can cross-restore the plurality of low-rate electrical signals into a high-rate target signal. In the above process, both the transmission end and the reception end can process the low-rate electrical signals using low-rate hardware devices, thereby realizing high-rate optical transmission based on low-cost and technologically advanced low-rate hardware devices and reducing the difficulty of realizing high-rate optical transmission.

[0035] In the embodiments of the present disclosure, the reception end performs cross restoration on the second upstream electrical signals in a plurality of lanes according to a preset granularity, that is, according to the rule by which the transmission end cross-divides the initial upstream signal, the plurality of second upstream electrical signals are restored to the target upstream signal.

[0036] In the present disclosure, there is no particular limitation on how to lane-align the second upstream electrical signals in a plurality of lanes according to the upstream granularity.

[0037] In some embodiments, the upstream alignment flag bit is carried in the second upstream electrical signal, and the second upstream electrical signals in the plurality of lanes are aligned based on the upstream alignment flag bits of the plurality of second upstream electrical signals.

[0038] Correspondingly, referring to FIG. 2, the step of lane-aligning the second upstream electrical signals in the plurality of lanes according to the upstream granularity (i.e., step S13) includes the following steps S131 to S132.

[0039] In step S131, analyze the second upstream electrical signal in each lane and determine the upstream alignment flag bit of the second upstream electrical signal in each lane.

[0040] In step S132, align the second upstream electrical signals in the plurality of lanes based on the upstream alignment flag bits of the second upstream electrical signals in each lane.

[0041] In the present disclosure, the upstream alignment flag bit in the second upstream electrical signal is not particularly limited.

[0042] In some embodiments, when the transmitting end divides the initial upstream signal into a plurality of first upstream electrical signals, a specific bit sequence is carried as the upstream alignment flag bit in the first upstream electrical signal, and this upstream alignment flag bit is also carried in the plurality of second upstream electrical signals obtained by the receiving end based on the upstream optical signal.

[0043] In some embodiments, after combining the bit streams obtained by cross-dividing a specific field in the initial upstream signal, it is used as the upstream alignment flag bit.

[0044] Correspondingly, in some embodiments, referring to FIG. 3, the step of analyzing the second upstream electrical signal in each lane and determining the upstream alignment flag bit of the second upstream electrical signal in each lane (i.e., step S131) includes the following steps S131a to S131b.

[0045] In step S131a, for the second upstream electrical signal in any lane, a first upstream data block in the second upstream electrical signal is determined. Here, the first upstream data block corresponds to a plurality of data fragments of the first upstream identifier in the initial upstream signal.

[0046] In step S131b, an upstream alignment flag bit of the second upstream electrical signal is determined based on the first upstream data block.

[0047] In the first upstream identifier, the plurality of data fragments corresponding to the first upstream data blocks in the plurality of lanes are arranged crosswise with each other.

[0048] In addition, in the embodiment of the present disclosure, the first upstream data block is obtained by combining bitstreams obtained by cross-dividing the first upstream identifier. That is, a plurality of data fragments in the first upstream identifier are combined to obtain the first upstream data block, and the data fragments corresponding to the first upstream data blocks in the plurality of lanes are arranged crosswise with each other within the first upstream identifier. Therefore, by arranging the data fragments within the first upstream data blocks in the plurality of lanes crosswise with each other, the first upstream identifier can be restored and obtained.

[0049] In the present disclosure, the first upstream identifier, that is, the specific field corresponding to the bit stream as the upstream alignment flag bit in the initial upstream signal is not particularly limited. In some embodiments, the first upstream identifier is related to an upstream physical synchronization block (PSBu) in the upstream direction. For example, when the initial upstream signal is a non-interleaved bit stream, the first upstream identifier is the delimiter in the PSBu, and when the initial upstream signal is an interleaved bit stream, the first upstream identifier is a specific bit stream formed after interleaving the delimiter in the PSBu, which has a strong correlation with the depth of interleaving.

[0050] In some embodiments, the bit streams obtained by cross-dividing the first upstream identifier are combined to serve as the upstream alignment flag bits. For example, when the number of lanes is 2, the first upstream identifier is the delimiter, the bit stream composed of the odd fragments of the delimiter is combined to serve as the upstream alignment flag bit of one lane, and the bit stream composed of the even fragments of the delimiter is combined to serve as the upstream alignment flag bit of another lane.

[0051] Correspondingly, in some embodiments, the step of determining the upstream alignment flag bit of the second upstream electrical signal based on the first upstream data block (that is, step S131b) includes the step of using the first upstream data block as the upstream alignment flag bit of the second upstream electrical signal.

[0052] In some embodiments, when determining the upstream alignment flag bit of the second upstream electrical signal based on the first upstream data block, by expanding the first upstream data block, cross-division is performed to avoid increasing the probability of synchronization error due to the length of the upstream alignment flag bit being shorter than the length of the first upstream identifier.

[0053] In the present disclosure, there is no particular limitation on how to extend the first upstream data block.

[0054] In some embodiments, the first upstream data blocks of two consecutive physical frames in the second upstream electrical signal are combined to form an upstream alignment flag bit.

[0055] Correspondingly, in some embodiments, the step of determining the upstream alignment flag bit of the second upstream electrical signal based on the first upstream data block (i.e., step S131b) includes the step of combining the first upstream data blocks of two consecutive physical frames in a lane to obtain the upstream alignment flag bit of the second upstream electrical signal.

[0056] In some embodiments, the length of the first upstream data block is extended to form an upstream alignment flag bit.

[0057] Correspondingly, in some embodiments, the step of determining the upstream alignment flag bit of the second upstream electrical signal based on the first upstream data block (i.e., step S131b) includes the step of extending the length of the first upstream data block to obtain the upstream alignment flag bit of the second upstream electrical signal, and the length of the extended first upstream data block is equal to the length of the first upstream identifier.

[0058] In the present disclosure, there is no particular limitation on how to extend the length of the first upstream data block. For example, the length of the first upstream data block may be extended by means such as replication and exclusive OR operation.

[0059] In some embodiments, the synchronization performance is determined by detecting the decoding status of a forward error correction (FEC) code and the deframing status of a Gigabit-Capable PON (GPON) Encapsulation Mode (GEM) frame. Once the synchronization performance degrades, resynchronization is performed, thereby avoiding increasing the probability of a synchronization error due to cross-division causing the length of the upstream alignment flag bit to be shorter than the length of the first upstream identifier.

[0060] Correspondingly, in some embodiments, referring to FIG. 4, after lane-aligning the second upstream electrical signals in a plurality of lanes according to the upstream granularity and restoring them after alignment to obtain a target upstream signal (i.e., step S13), the data transmission method further includes the following steps S141 to S142.

[0061] In step S141, a first accuracy rate for decoding the FEC code in the target upstream signal and a second accuracy rate for deframing the GEM frame are determined.

[0062] In step S142, when the first accuracy rate is lower than a first threshold and / or the second accuracy rate is lower than a second threshold, the data is resynchronized.

[0063] In some embodiments, the first accuracy rate and the second accuracy rate are characterized using the number of correctly decoded FEC codes and the number of correctly deframed GEM frames, and the synchronization performance can be determined by determining the number of correctly decoded FEC codes and / or the number of correctly deframed GEM frames.

[0064] The embodiments of the present disclosure also provide countermeasures for upstream false lock.

[0065] In some embodiments, the preamble pattern is a pseudo-random binary sequence (PRBS) code type configured by the OLT, with an indefinite length. When it is split into two lanes for transmission, it becomes the same as one of the split results of the Delimiter of the PSBu segment, and there is a possibility that the OLT side will false lock the ONU. By comparing the preamble corresponding to the Delimiter with the preset preamble, false locking can be avoided.

[0066] Correspondingly, in some embodiments, referring to FIG. 5, the data transmission method further includes the following steps S151 to S153.

[0067] In step S151, based on the first upstream data blocks in a plurality of lanes, a second upstream identifier corresponding to the first upstream identifier is determined.

[0068] In step S152, the ratio of the bits of the preamble before the second upstream identifier that are the same as the preset preamble is determined.

[0069] In step S153, if the determined ratio is lower than a third threshold, the second upstream identifier is re-determined.

[0070] In the embodiments of the present disclosure, when the first identifier in the initial upstream signal is a Delimiter, the second upstream identifier is the Delimiter in the target upstream signal.

[0071] In some embodiments, after cross-dividing a high-rate initial upstream signal into a plurality of low-rate electrical signals, the original order relationship between 0 and 1 in the first upstream identifier changes. As a result, the receiving end may misjudge the transmitting end as abnormal and false lock may occur. For example, after the OLT receives the data of the ONU, it may misjudge the ONU as an illegal ONU. False lock can be avoided by detecting each burst packet.

[0072] Correspondingly, in some embodiments, referring to FIG. 6, the data transmission method further includes the following steps S161 to S162.

[0073] In step S161, based on the first upstream data blocks in a plurality of lanes, a second upstream identifier corresponding to the first upstream identifier is determined.

[0074] In step S162, based on the second upstream identifier, it is determined whether the ONU that transmits the upstream optical signal is abnormal.

[0075] In some embodiments, steps S161 and S162 are realized by performing alignment once after synchronization, detecting PSBu, checking whether there is an illegal ONU, and further processing using the illegal ONU mechanism if there is an illegal ONU.

[0076] In the present disclosure, there is no particular limitation on how to generate the second upstream electrical signals in a plurality of lanes based on the upstream optical signal.

[0077] In some embodiments, the transmitting end modulates the first upstream electrical signals in a plurality of lanes to obtain an upstream optical signal. Correspondingly, the receiving end obtains the second upstream electrical signals in a plurality of lanes by demodulating the upstream optical signal.

[0078] Correspondingly, in some embodiments, the step of generating a second upstream electrical signal in a plurality of lanes based on the upstream optical signal (i.e., step S12) includes the step of demodulating the upstream optical signal to obtain the second upstream electrical signal in the plurality of lanes.

[0079] Referring to FIG. 7, an embodiment of the present disclosure further provides a data transmission method including the following steps S21 to S23.

[0080] In step S21, an initial upstream signal is cross-divided according to the upstream granularity to obtain a first upstream electrical signal in a plurality of lanes.

[0081] In step S22, one upstream optical signal is generated based on the first upstream electrical signals in the plurality of lanes.

[0082] In step S23, the upstream optical signal is transmitted.

[0083] The data transmission method according to the embodiment of the present disclosure is applied to the transmitting end in the upstream direction. In the embodiment of the present disclosure, in the upstream direction, the ONU is the transmitting end and the OLT is the receiving end.

[0084] In the embodiment of the present disclosure, at the transmitting end, after cross-dividing the initial upstream signal according to a preset upstream granularity to obtain the first upstream electrical signals in a plurality of lanes, one upstream optical signal is generated based on the first upstream electrical signals in the plurality of lanes and transmitted to the upstream receiving end. In the present disclosure, the number of lanes is not particularly limited and may be, for example, 2, 4, 8, etc.

[0085] In addition, in the embodiments of the present disclosure, the upstream transmission end cross-dividing the initial upstream signal according to a preset upstream granularity refers to dividing the initial upstream signal into a plurality of data fragments according to the preset upstream granularity, where the data fragment consists of at least 1 bit (bit) satisfying the preset upstream granularity among the initial upstream signals. Assuming that the upstream transmission end has X lanes, adjacent X data fragments in the initial upstream signal are respectively divided into X different lanes, and the bit stream composed of the data fragments divided into each lane becomes the first upstream electrical signal in each lane. For example, the upstream transmission end has X lanes, and the preset upstream granularity is N bit, that is, the initial upstream signal is divided into one data fragment every N bit, and the bit stream combining the (iX)Nth bit and the subsequent N - 1 bits is used as the first upstream electrical signal in one lane, and the bit stream combining the (iX + 1)Nth bit and the subsequent N - 1 bits is used as the first upstream electrical signal in one lane,..., and by using the bit stream combining the (iX + X - 1)Nth bit and the subsequent N - 1 bits as the first upstream electrical signal in one lane, X first upstream electrical signals corresponding to the X lanes are obtained respectively, and i takes values in the order of 0, 1, 2, 3,....

[0086] In some embodiments, the number of lanes at the upstream transmission end is 2. When cross-dividing the initial upstream signal according to the preset upstream granularity, the plurality of data fragments obtained by dividing the initial upstream signal can be divided into odd fragments and even fragments. The bit stream after combining the odd fragments is used as one first upstream electrical signal, and the bit stream after combining the even fragments is used as another first upstream electrical signal.

[0087] In the present disclosure, the preset granularity is not particularly limited. For example, the preset granularity may be 1 bit, 4 bit, or 8 bit.

[0088] In an embodiment of the present disclosure, the upstream transmission end cross-divides the initial upstream signal and plays a role in reducing the rate of the NRZ signal, that is, the rates of a plurality of first upstream electrical signals obtained by cross-dividing the initial upstream signal are smaller than the rate of the initial upstream signal. In some embodiments, the sum of the rates of the plurality of first upstream electrical signals is equal to the rate of the initial upstream signal. For example, the initial upstream signal is a 50G NRZ signal, and two 25G NRZ signals are obtained by cross-division, or the initial upstream signal is a 100G NRZ signal, and two 50G NRZ signals are obtained by cross-division, or the initial upstream signal is a 100G NRZ signal, and four 25G NRZ signals are obtained by cross-division.

[0089] In an embodiment of the present disclosure, by reducing the rate of the NRZ signal, high-rate optical transmission can be realized using low-rate hardware devices. For example, if the initial upstream signal is a 50G NRZ signal, it is cross-divided into two 25G NRZ signals at the transmission end and restored to a 50G NRZ signal at the reception end. Here, the transmission end and the reception end can process the two 25G NRZ signals based on 25G hardware devices, and also realize 50G optical transmission based on 25G hardware devices by transmitting with a 50G optical signal.

[0090] According to the data transmission method according to an embodiment of the present disclosure, in the upstream direction, the transmission end cross-divides a high-rate initial signal into a plurality of low-rate electrical signals and transmits them to the reception end by a high-rate optical signal, and the reception end can cross-restore the plurality of low-rate electrical signals into a high-rate target signal. In the above process, both the transmission end and the reception end can process low-rate electrical signals using low-rate hardware devices, thereby realizing high-rate optical transmission based on low-cost and technologically advanced low-rate hardware devices and reducing the difficulty of realizing high-rate optical transmission.

[0091] In the present disclosure, there is no particular limitation on how to generate one upstream optical signal based on the first upstream electrical signals in a plurality of lanes.

[0092] In some embodiments, the step of generating one upstream optical signal based on the first upstream electrical signals in a plurality of lanes (i.e., step S22) includes modulating the first upstream electrical signals in the plurality of lanes to obtain an upstream optical signal.

[0093] Referring to FIG. 8, an embodiment of the present disclosure further provides a data transmission method including the following steps S31 to S33.

[0094] In step S31, a downstream optical signal is received.

[0095] In step S32, second downstream electrical signals in a plurality of lanes are generated based on the downstream optical signal. Here, the second downstream electrical signals in the plurality of lanes respectively correspond to the first downstream electrical signals in the plurality of lanes obtained by the downstream transmitting end cross-dividing an initial downstream signal according to the downstream granularity.

[0096] In step S33, the second downstream electrical signals in the plurality of lanes are lane-aligned according to the downstream granularity, and after alignment, they are restored to obtain a target downstream signal.

[0097] The data transmission method according to the embodiment of the present disclosure is applied to the receiving end in the downstream direction. In the embodiment of the present disclosure, in the downstream direction, the OLT is the transmitting end and the ONU is the receiving end.

[0098] In an embodiment of the present disclosure, a downstream receiving end receives an optical signal transmitted from a downstream transmitting end. At the downstream transmitting end, an initial downstream signal is cross-divided according to a preset downstream granularity to obtain first downstream electrical signals in a plurality of lanes, and then one downstream optical signal is generated based on the first downstream electrical signals in the plurality of lanes and transmitted to the downstream receiving end. The downstream receiving end generates second downstream electrical signals in a plurality of lanes based on the received downstream optical signal, where the plurality of second downstream electrical signals of the downstream receiving end and the plurality of first downstream electrical signals of the downstream transmitting end correspond one-to-one, that is, the number of lanes of the downstream transmitting end is the same as the number of lanes of the downstream receiving end, and the plurality of lanes of the downstream transmitting end and the plurality of lanes of the downstream receiving end correspond one-to-one. In the present disclosure, the number of lanes is not particularly limited and may be, for example, 2, 4, 8, etc.

[0099] In the embodiments of the present disclosure, the cross - splitting of the initial downlink signal by the downlink transmitting end according to a preset downlink granularity refers to splitting the initial downlink signal into a plurality of data fragments according to the preset downlink granularity. Here, a data fragment consists of at least 1 bit (bit) that satisfies the preset downlink granularity among the initial downlink signals. Assuming that the downlink transmitting end has X lanes, adjacent X data fragments in the initial downlink signal are respectively split into X different lanes, and the bit stream composed of the data fragments split into each lane becomes the first downlink electrical signal in each lane. For example, the downlink transmitting end has X lanes, and the preset downlink granularity is N bit, that is, the initial downlink signal is split into one data fragment every N bit. The bit stream formed by combining the (iX) - th bit and the subsequent N - 1 bits is used as the first downlink electrical signal in one lane, the bit stream formed by combining the (iX + 1) - th bit and the subsequent N - 1 bits is used as the first downlink electrical signal in one lane, ……, the bit stream formed by combining the (iX+X - 1) - th bit and the subsequent N - 1 bits is used as the first downlink electrical signal in one lane. In this way, X first downlink electrical signals corresponding to X lanes are obtained, and i takes values in the order of 0, 1, 2, 3, ….

[0100] In some embodiments, the number of lanes at the downlink transmitting end is 2. When cross - splitting the initial downlink signal according to the preset downlink granularity, the plurality of data fragments obtained by splitting the initial downlink signal can be split into odd - numbered fragments and even - numbered fragments. The bit stream after combining the odd - numbered fragments is used as one first downlink electrical signal, and the bit stream after combining the even - numbered fragments is used as another first downlink electrical signal.

[0101] In the present disclosure, the preset granularity is not particularly limited. For example, the preset granularity may be 1 bit, 4 bit, or 8 bit.

[0102] In the present disclosure, the initial downlink signal is not particularly limited. For example, the initial downlink signal can be any one of an NRZ signal, a PAM4 signal, a scrambled bitstream, or an interleaved bitstream (Bitstream Scrambling / Bitstream Interleaving).

[0103] In an embodiment of the present disclosure, the downlink transmitting end performs cross-division on the initial downlink signal and serves to reduce the rate of the NRZ signal. That is, the rates of a plurality of first downlink electrical signals obtained by cross-dividing the initial downlink signal are smaller than the rate of the initial downlink signal. In some embodiments, the sum of the rates of the plurality of first downlink electrical signals is equal to the rate of the initial downlink signal. For example, if the initial downlink signal is a 50G NRZ signal, two 25G NRZ signals are obtained by cross-division, or if the initial downlink signal is a 100G NRZ signal, two 50G NRZ signals are obtained by cross-division, or if the initial downlink signal is a 100G NRZ signal, four 25G NRZ signals are obtained by cross-division.

[0104] In an embodiment of the present disclosure, the rates of a plurality of second downlink electrical signals generated based on the downlink optical signal received by the downlink transmitting end are the same as the rates of the plurality of first downlink electrical signals at the transmitting end. For example, when the downlink transmitting end generates two 25G NRZ signals, the downlink receiving end generates two 25G NRZ signals based on the downlink optical signal. When the downlink transmitting end generates four 25G NRZ signals, the downlink receiving end generates four 25G NRZ signals based on the downlink optical signal. The downlink receiving end performs cross-restoration on the second downlink electrical signals in a plurality of lanes according to a preset granularity, that is, according to the rule by which the downlink transmitting end performs cross-division on the initial downlink signal, the plurality of second downlink electrical signals are restored to a target downlink signal. In some embodiments, the target downlink signal is the same as the initial downlink signal. In some embodiments, the target downlink signal is an approximation of the initial downlink signal.

[0105] Note that the rate of the target downlink signal obtained by the downlink transmission end through cross restoration is the same as the rate of the initial downlink signal, and the rate of the downlink optical signal transmitted between the transmission end and the reception end is the same as the rate of the initial downlink signal. Thus, high-rate optical transmission can be realized using low-rate hardware devices. For example, if the initial downlink signal is a 50G NRZ signal, it is cross-divided into two 25G NRZ signals at the transmission end and restored to a 50G NRZ signal at the reception end to obtain the target downlink signal. Here, the transmission end and the reception end can process the two 25G NRZ signals based on 25G hardware devices, and by transmitting with a 50G optical signal, 50G optical transmission based on 25G hardware devices can be realized.

[0106] According to the data transmission method according to the embodiments of the present disclosure, in the downlink direction, the transmission end cross-divides a high-rate initial signal into a plurality of low-rate electrical signals and transmits them to the reception end through a high-rate optical signal, and the reception end can cross-restore the plurality of low-rate electrical signals into a high-rate target signal. In the above process, both the transmission end and the reception end can process low-rate electrical signals using low-rate hardware devices, thereby realizing high-rate optical transmission based on lower-cost and more technologically advanced low-rate hardware devices and reducing the difficulty of realizing high-rate optical transmission.

[0107] In the embodiments of the present disclosure, the reception end performs cross restoration on the second downlink electrical signals in a plurality of lanes according to a preset granularity, that is, according to the rule by which the transmission end cross-divides the initial downlink signal, the plurality of second downlink electrical signals are restored to the target downlink signal.

[0108] In the present disclosure, there is no particular limitation on how to lane-align the second downlink electrical signals in a plurality of lanes according to the downlink granularity.

[0109] In some embodiments, the downstream alignment flag bit is carried in the second downstream electrical signal, and the second downstream electrical signals in the plurality of lanes are aligned based on the downstream alignment flag bits of the plurality of second downstream electrical signals.

[0110] Correspondingly, referring to FIG. 9, the step of lane-aligning the second downstream electrical signals in the plurality of lanes according to the downstream granularity (i.e., step S33) includes the following steps S331 to S332.

[0111] In step S331, analyze the second downstream electrical signal in each lane and determine the downstream alignment flag bit of the second downstream electrical signal in each lane.

[0112] In step S332, align the second downstream electrical signals in the plurality of lanes based on the downstream alignment flag bits of the second downstream electrical signals in each lane.

[0113] In the present disclosure, the downstream alignment flag bit in the second downstream electrical signal is not particularly limited.

[0114] In some embodiments, when the transmitting end divides the initial downstream signal into a plurality of first downstream electrical signals, a specific bit sequence is carried as the downstream alignment flag bit in the first downstream electrical signal, and this downstream alignment flag bit is also carried in the plurality of second downstream electrical signals obtained by the receiving end based on the downstream optical signal.

[0115] In some embodiments, after combining the bit streams obtained by cross-dividing a specific field in the initial downstream signal, it is used as the downstream alignment flag bit.

[0116] Correspondingly, in some embodiments, referring to FIG. 10, the step of analyzing the second downstream electrical signal in each lane and determining the downstream alignment flag bit of the second downstream electrical signal in each lane (i.e., step S331) includes the following steps S331a to S331b.

[0117] In step S331a, for the second downstream electrical signal in any lane, a first downstream data block in the second downstream electrical signal is determined. Here, the first downstream data block corresponds to a plurality of data fragments of the first downstream identifier in the initial downstream signal.

[0118] In step S331b, a downstream alignment flag bit of the second downstream electrical signal is determined based on the first downstream data block.

[0119] In the first downstream identifier, the plurality of data fragments corresponding to the first downstream data blocks in the plurality of lanes are arranged crosswise with each other.

[0120] In addition, in the embodiments of the present disclosure, the first downstream data block is obtained by combining bitstreams obtained by cross-dividing the first downstream identifier. That is, the first downstream data block is obtained by combining a plurality of data fragments in the first downstream identifier, and the data fragments corresponding to the first downstream data blocks in the plurality of lanes are arranged crosswise with each other within the first downstream identifier. Therefore, by arranging the data fragments within the first downstream data blocks in the plurality of lanes crosswise with each other, the first downstream identifier can be restored and obtained.

[0121] In the present disclosure, there is no particular limitation on the first downstream identifier, that is, the specific field corresponding to the bit stream as the downstream alignment flag bit in the initial downstream signal. In some embodiments, the first downstream identifier is related to the physical synchronization sequence (PSync) in the downstream physical synchronization block (PSBd) in the downstream direction. For example, when the initial downstream signal is a non-interleaved bit stream, the first downstream identifier is the PSync in the PSBd. When the initial downstream signal is an interleaved bit stream, the first downstream identifier is a specific bit stream formed after interleaving the PSync in the PSBd, and there is a strong correlation with the depth of interleaving.

[0122] In some embodiments, the bit streams obtained by cross-splitting the first downstream identifier are combined to be the downstream alignment flag bits. For example, when the number of lanes is 2, the first downstream identifier is the PSync, the bit stream composed of the odd fragments of the PSync is combined to be the downstream alignment flag bit of one lane, and the bit stream composed of the even fragments of the PSync is combined to be the downstream alignment flag bit of another lane.

[0123] Correspondingly, in some embodiments, the step of determining the downstream alignment flag bit of the second downstream electrical signal based on the first downstream data block (i.e., step S331b) includes the step of using the first downstream data block as the downstream alignment flag bit of the second downstream electrical signal.

[0124] In some embodiments, when determining the downstream alignment flag bit of the second downstream electrical signal based on the first downstream data block, by expanding the first downstream data block, cross-splitting is performed to avoid increasing the probability of synchronization error due to the length of the downstream alignment flag bit being shorter than the length of the first downstream identifier.

[0125] In the present disclosure, there is no particular limitation on how to expand the first downstream data block.

[0126] In some embodiments, the first downstream data blocks of two consecutive physical frames in the second downstream electrical signal are combined to form a downstream alignment flag bit.

[0127] Correspondingly, in some embodiments, the step of determining the downstream alignment flag bit of the second downstream electrical signal based on the first downstream data block (i.e., step S331b) includes the step of combining the first downstream data blocks of two consecutive physical frames in a lane to obtain the downstream alignment flag bit of the second downstream electrical signal.

[0128] In some embodiments, the length of the first downstream data block is expanded to form a downstream alignment flag bit.

[0129] Correspondingly, in some embodiments, the step of determining the downstream alignment flag bit of the second downstream electrical signal based on the first downstream data block (i.e., step S331b) includes the step of expanding the length of the first downstream data block to obtain the downstream alignment flag bit of the second downstream electrical signal, and the length of the expanded first downstream data block is equal to the length of the first downstream identifier.

[0130] In the present disclosure, there is no particular limitation on how to expand the length of the first downstream data block. For example, the length of the first downstream data block may be expanded by means such as replication and exclusive OR operation.

[0131] In some embodiments, the synchronization performance is determined by detecting the decoding status of the FEC code and the deframing status of the GEM frame. Once the synchronization performance deteriorates, resynchronization is performed, thereby avoiding increasing the probability of synchronization errors due to cross-division resulting in the length of the downstream alignment flag bit being shorter than the length of the first identifier.

[0132] Correspondingly, in some embodiments, referring to FIG. 11, after aligning the second downstream electrical signals in multiple lanes according to the downstream granularity and restoring them after alignment to obtain the target downstream signal (i.e., step S33), the data transmission method further includes the following steps S341 to S342.

[0133] In step S341, determine a third accuracy rate for decoding the FEC code in the target downstream signal and a fourth accuracy rate for deframing the GEM frame.

[0134] In step S342, when the third accuracy rate is lower than a fourth threshold and / or the fourth accuracy rate is lower than a fifth threshold, resynchronize the data.

[0135] In some embodiments, characterize the third accuracy rate and the fourth accuracy rate using the number of correctly decoded FEC codes and the number of correctly deframed GEM frames, and determine the synchronization performance by determining the number of correctly decoded FEC codes and / or the number of correctly deframed GEM frames.

[0136] In the present disclosure, there is no particular limitation on how to generate the second downstream electrical signals in multiple lanes based on the downstream optical signal.

[0137] In some embodiments, the transmitting end modulates the first downstream electrical signals in multiple lanes to obtain a downstream optical signal, and correspondingly, the receiving end demodulates the downstream optical signal to obtain the second downstream electrical signals in multiple lanes.

[0138] Correspondingly, in some embodiments, the step of generating the second downstream electrical signals in multiple lanes based on the downstream optical signal (i.e., step S32) includes the step of demodulating the downstream optical signal to obtain the second downstream electrical signals in multiple lanes.

[0139] Referring to FIG. 12, an embodiment of the present disclosure further provides a data transmission method including the following steps S41 to S43.

[0140] In step S41, the initial downlink signal is cross-divided according to the downlink granularity to obtain the first downlink electrical signals in a plurality of lanes.

[0141] In step S42, one downlink optical signal is generated based on the first downlink electrical signals in the plurality of lanes.

[0142] In step S43, the downlink optical signal is transmitted.

[0143] The data transmission method according to the embodiment of the present disclosure is applied to the transmission end in the downlink direction. In the embodiment of the present disclosure, in the downlink direction, the OLT is the transmission end and the ONU is the reception end.

[0144] In the embodiment of the present disclosure, at the transmission end, the initial downlink signal is cross-divided according to the preset downlink granularity to obtain the first downlink electrical signals in a plurality of lanes, and then one downlink optical signal is generated based on the first downlink electrical signals in the plurality of lanes and transmitted to the downlink reception end. In the present disclosure, the number of lanes is not particularly limited, and may be, for example, 2, 4, 8, etc.

[0145] In the embodiments of the present disclosure, the cross-division of the initial downlink signal by the downlink transmitting end according to a preset downlink granularity refers to dividing the initial downlink signal into a plurality of data fragments according to the preset downlink granularity. Here, a data fragment consists of at least 1 bit (bit) that satisfies the preset downlink granularity among the initial downlink signals. Assuming that the downlink transmitting end has X lanes, adjacent X data fragments in the initial downlink signal are respectively divided into X different lanes, and the bit stream composed of the data fragments divided into each lane becomes the first downlink electrical signal in each lane. For example, the downlink transmitting end has X lanes, and the preset downlink granularity is N bit, that is, the initial downlink signal is divided into one data fragment every N bit. The bit stream combining the (iX)th bit and the subsequent N - 1 bits is used as the first downlink electrical signal in one lane, and the bit stream combining the (iX + 1)th bit and the subsequent N - 1 bits is used as the first downlink electrical signal in one lane,..., and by using the bit stream combining the (iX + X - 1)th bit and the subsequent N - 1 bits as the first downlink electrical signal in one lane, X first downlink electrical signals corresponding to X lanes respectively can be obtained, where i takes values in the order of 0, 1, 2, 3,....

[0146] In some embodiments, the number of lanes at the downlink transmitting end is 2. When cross-dividing the initial downlink signal according to a preset downlink granularity, the plurality of data fragments obtained by dividing the initial downlink signal can be divided into odd fragments and even fragments. The bit stream after combining the odd fragments is used as one first downlink electrical signal, and the bit stream after combining the even fragments is used as another first downlink electrical signal.

[0147] In the present disclosure, the preset granularity is not particularly limited. For example, the preset granularity may be 1 bit, 4 bit, or 8 bit.

[0148] In an embodiment of the present disclosure, the downlink transmission end performs cross-division on the initial downlink signal and plays a role in reducing the rate of the NRZ signal. That is, the rates of a plurality of first downlink electrical signals obtained by cross-dividing the initial downlink signal are smaller than the rate of the initial downlink signal. In some embodiments, the sum of the rates of the plurality of first downlink electrical signals is equal to the rate of the initial downlink signal. For example, the initial downlink signal is a 50G NRZ signal, and two 25G NRZ signals are obtained by cross-division, or the initial downlink signal is a 100G NRZ signal, and two 50G NRZ signals are obtained by cross-division, or the initial signal is a 100G NRZ signal, and four 25G NRZ signals are obtained by cross-division.

[0149] In an embodiment of the present disclosure, by reducing the rate of the NRZ signal, high-rate optical transmission can be realized using low-rate hardware devices. For example, if the initial downlink signal is a 50G NRZ signal, it is cross-divided into two 25G NRZ signals at the transmission end and restored to a 50G NRZ signal at the reception end. Here, the transmission end and the reception end can process the two 25G NRZ signals based on 25G hardware devices, and by transmitting with a 50G optical signal, 50G optical transmission based on 25G hardware devices can be realized.

[0150] According to the data transmission method according to an embodiment of the present disclosure, in the downlink direction, the transmission end cross-divides a high-rate initial signal into a plurality of low-rate electrical signals and transmits them to the reception end by a high-rate optical signal, and the reception end can cross-restore the plurality of low-rate electrical signals into a high-rate target signal. In the above process, both the transmission end and the reception end can process low-rate electrical signals using low-rate hardware devices, thereby realizing high-rate optical transmission based on low-cost and technologically advanced low-rate hardware devices and reducing the difficulty of realizing high-rate optical transmission.

[0151] In the present disclosure, there is no particular limitation on how to generate one downstream optical signal based on the first downstream electrical signals in a plurality of lanes.

[0152] In some embodiments, the step of generating one downstream optical signal based on the first downstream electrical signals in a plurality of lanes (i.e., step S42) includes modulating the first downstream electrical signals in the plurality of lanes to obtain a downstream optical signal.

[0153] Referring to FIG. 13, an embodiment of the present disclosure further provides an OLT including one or more processors 101 and a memory storing one or more programs, where when the one or more programs are executed by the one or more processors, the one or more processors are caused to implement the data transmission method according to the embodiment of the present disclosure shown in FIGS. 1 to 6 and / or the data transmission method according to the embodiment of the present disclosure shown in FIG. 12.

[0154] Further, the OLT further includes one or more I / O interfaces 103 connected between the processor and the memory and configured to realize the exchange of information between the processor and the memory.

[0155] The processor 101 is a device having data processing capabilities, including but not limited to a central processing unit (CPU), etc. The memory 102 is a device having data storage capabilities, including but not limited to random access memory (RAM, more specifically SDRAM, DDR, etc.), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), and flash memory (FLASH). The I / O interface (read / write interface) 103 is connected between the processor 101 and the memory 102 and can realize the exchange of information between the processor 101 and the memory 102, including but not limited to a data bus (Bus), etc.

[0156] In some embodiments, the processor 101, the memory 102, and the I / O interface 103 are connected to each other via a bus 104, thereby connecting to other components of the computing device.

[0157] In some embodiments, the OLT includes an OLT chip, and the OLT chip has a plurality of electrical interfaces each corresponding to one lane.

[0158] In some embodiments, the OLT includes an optoelectronic conversion chip and a media access control (MAC) layer chip, and a plurality of lanes are included from the optoelectronic conversion chip to the MAC layer chip.

[0159] Referring to FIG. 14, embodiments of the present disclosure further provide an ONU including one or more processors 201 and a memory storing one or more programs, where when the one or more programs are executed by the one or more processors, the one or more processors are caused to implement the data transmission method according to the embodiments of the present disclosure described in FIGS. 7 to 11.

[0160] The ONU further includes one or more I / O interfaces 203 connected between the processor and the memory and configured to realize the exchange of information between the processor and the memory.

[0161] Processor 201 is a device with data processing capabilities, including but not limited to a central processing unit (CPU), etc. Memory 202 is a device with data storage capabilities, including but not limited to random access memory (RAM, more specifically SDRAM, DDR, etc.), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), and flash memory (FLASH). The I / O interface (read / write interface) 203 is connected between the processor 201 and the memory 202, and can realize the exchange of information between the processor 201 and the memory 202, including but not limited to a data bus (Bus), etc.

[0162] In some embodiments, the processor 201, the memory 202, and the I / O interface 203 are connected to each other via a bus 204, and thereby connected to other components of the computing device.

[0163] In some embodiments, the ONU includes an ONU chip, and the ONU chip has a plurality of electrical interfaces, each corresponding to one lane.

[0164] In some embodiments, the ONU includes an optical-electrical conversion chip and a media access control (MAC) layer chip, and a plurality of lanes are included from the optical-electrical conversion chip to the MAC layer chip.

[0165] Referring to FIG. 15, embodiments of the present disclosure further provide a computer-readable medium storing a computer program, which, when executed by a processor, causes the processor to implement the data transmission method according to each embodiment of the present disclosure.

[0166] In order for those skilled in the art to more clearly understand the technical solutions provided by the embodiments of the present disclosure, the following will use specific examples to describe in detail the technical solutions provided by the embodiments of the present disclosure.

[0167] Example 1 This example is applicable to the upstream and downstream data transmission environment of a 50G PON system and is applied to OLT and ONU devices. It adopts an N-bit granularity multiplexing and demultiplexing method. At the transmitting end, two 25Gbps NRZ lanes are used to complete 50Gbps data transmission, and at the receiving end, the original data is also restored in the form of a dual channel.

[0168] At the OLT transmitting end in the downstream direction, for each 50G NRZ electrical signal, every N-bit granularity length is parity-crossed to form two new 25G NRZ electrical signals. The PSync of the PSBd data block in the original OLT downstream physical frame is also parity-crossed at the N-bit granularity length to form two new bit streams. In this example, this bit stream is used as a flag for the ONU receiver for synchronization and data lane alignment.

[0169] Figure 16 is a schematic diagram of the data structure where the downstream PSync is located. For example, the bit stream formed by combining all the ANth bits of PSync and the subsequent N - 1 bits is used as the alignment flag bit of Lane0 (A is an even number, A = 0, 2, 4,...), and the bit stream formed by combining all the B Nth bits of PSync and the subsequent N - 1 bits is used as the alignment flag bit of Lane1 (B is an odd number, B = 1, 3, 5,...). At the receiving end, two 25G NRZ electrical signals are formed through optoelectronic conversion. At this time, the ONU uses the synchronization and data lane alignment flags formed on the OLT side to perform data synchronization, dual-lane data alignment, and restoration of 50G NRZ data.

[0170] At the ONU transmission end in the upstream direction, for each 50G NRZ electrical signal, it is also bit-interleaved at an N-bit granularity length for each frame to form two new 25G NRZ electrical signals. The delimiter of the last PSBu Segment in the original ONU upstream burst physical (Burst PHY) frame is also bit-interleaved at an N-bit granularity length to form two new bitstreams. In this example, this bitstream is used as a flag for the data lane alignment of the OLT receiver (the new bitstream formed by the preamble is used for upstream synchronization).

[0171] Figure 17 is a schematic diagram of the data structure where the delimiter is located. After the upstream data synchronization is completed, the data lane alignment flag formed by the delimiter is used for dual-lane data alignment and the restoration of 50G NRZ data. In the ITU-T standard, the delimiter length of the last PSBu Segment of each Burst PHY frame is fixed and can be configured as 32 bits or 64 bits. Therefore, the bitstream formed by combining all the CNth bits of the delimiter and the subsequent N - 1 bits can be used as the alignment flag bits of Lane0 (C is an even number, C = 0, 2, 4,...), and the bitstream formed by combining all the DNth bits of the delimiter and the subsequent N - 1 bits can be used as the alignment flag bits of Lane1 (D is an odd number, D = 1, 3, 5,...).

[0172] Example 2 This example corresponds to the downstream direction. Figure 18 is a schematic diagram of the OLT transmission end in the downstream direction, and Figure 19 is a schematic diagram of the ONU reception end in the downstream direction.

[0173] The OLT uses a first serial-parallel conversion module in the MAC layer to split 50G NRZ into two 25G NRZ downstream data by bit interleaving with an N-bit granularity length, and sends it to the optical transmitter via two independent lanes (lane 0 / lane 1). After receiving the two 25G NRZ electrical signals, the optical transmitter converts them into 50G optical signals and transmits them downstream to the ONU.

[0174] In this process, the first serial-parallel conversion module plays a role in reducing the rate of the NRZ signal, and the conversion can be performed by an external chip such as a DSP / FPGA alone or inside the MAC chip. Also, the optical transmission module may receive and modulate the electrical signals of the two NRZ lanes simultaneously and transmit them, or convert them into 50G NRZ electrical signals by rate interleaving and then transmit them after electro-optical conversion.

[0175] The ONU optical receiver receives the optical signal transmitted from the OLT, performs optoelectronic conversion to generate two 25G-rate NRZ data. The optical reception module is the same as the optical transmission module, that is, two 25G NRZ data can be obtained by demodulation.

[0176] Since the ONU receiver splits the electrical signal into two NRZ signals after optoelectronic conversion, it is necessary to analyze the data of the two lanes, find the flag used by the ONU receiver for synchronization and data lane alignment, and synchronize based on this to strictly align the data of the two lanes in time.

[0177] The data of the parity lanes obtained on the ONU side is subjected to cross restoration of the data according to the parity lane rule arranged by the first serial-parallel conversion module on the OLT side. The duration of 1 bit after restoration is 1 / 2 shorter than the duration of 1 bit in the parity lanes, and finally 50G-rate NRZ data is obtained.

[0178] In addition, 50G-rate PSync is defined as 8 bytes in ITU-T G.9804.3 standard. After being parity-crossed with an N-bit granularity length and converted into two 25G rates, it becomes 4 bytes, and the symbols used for synchronization of each lane are shortened by half, increasing the probability of synchronization errors. Therefore, it can be solved by adopting any of the following methods.

[0179] 1) Synchronization errors can be reduced by using two consecutive 25G-rate physical frames in each lane as the synchronization state machine jump condition together. 2) Increase the length of the synchronization flag of each lane to 8 bytes. 3) Determine the synchronization status of the downstream receiving end by correctly decoding M FECs and correctly deframing K GEM frames (M and K are configurable, for example, M = 3, K = 1), and perform resynchronization if the synchronization performance deteriorates.

[0180] Example 3 This example corresponds to the upstream direction. Figure 20 is a schematic diagram of the ONU transmitting end in the upstream direction, and Figure 21 is a schematic diagram of the OLT receiving end in the upstream direction.

[0181] In the upstream direction, the MAC layer of the ONU uses the second serial-parallel conversion module to divide 50G NRZ into two 25G NRZ upstream data with an N-bit granularity length by parity crossing, and sends them to the optical transmitter via two independent lanes (lane 0 / lane 1). After receiving two 25G NRZ electrical signals, the optical transmitter converts them into 50G optical signals and transmits them upstream to the OLT.

[0182] In this process, the second serial-parallel conversion module plays a role in reducing the rate of the NRZ signal, and the conversion can be performed by an external chip such as DSP / FPGA alone or inside the MAC chip. In addition, the optical transmission module may receive and modulate the electrical signals of the two NRZ lanes simultaneously and transmit them, or convert them into 50G NRZ electrical signals by rate interleaving and then transmit them after electro-optical conversion.

[0183] The OLT optical receiver receives the optical signal transmitted from the ONU, performs optoelectronic conversion, and generates two 25G-rate NRZ data. The optical receiving module is the same as the optical transmitting module, that is, two 25G NRZ data can be obtained in the form of demodulation or deinterleaving, etc.

[0184] Since the OLT receiver divides the electrical signal into two NRZ signals after optoelectronic conversion, it is necessary to analyze the data of two lanes, find the flag used by the OLT receiver for synchronization and data lane alignment, and synchronize based on this to strictly align the data of the two lanes in time.

[0185] According to the parity lane rule arranged by the second serial-parallel conversion module on the ONU side for the data of the parity lanes obtained on the OLT side, perform cross restoration of the data. The continuous time of 1 bit after restoration is 1 / 2 shorter than the continuous time of 1 bit in the parity lanes, and finally 50G-rate NRZ data is obtained.

[0186] Also, when the 50G-rate data is divided into two 25G-rate data according to parity, the original order relationship of 0 and 1 will change, and there is a possibility that the OLT side will receive the data of the ONU during the upstream process and misjudge it as an illegal ONU, resulting in false lock. In this case, it can be avoided by detecting each burst packet (the head of each burst packet must be PSBu). That is, after synchronization, first perform alignment to detect PSBu, confirm the presence of an illegal ONU, and if there is an illegal ONU, further process it using the illegal ONU mechanism.

[0187] Also, the preamble pattern is a PRBS code type configured by the OLT, with an indefinite length. When it is split into two lanes for transmission, it may become the same as one of the split results of the Delimiter in the PSBu Segment, and there is a possibility that the OLT may false lock the ONU. In this case, the OLT needs to avoid this by determining whether at least P bits out of the L bits of the previous preamble part corresponding to the recognized Delimiter identifier are the same as the preset preamble (L and P are configurable, for example, L = 64, P = 57). If they are the same, it is not a false lock, but if not, it is a false lock, and the OLT needs to re-recognize the position of the Delimiter.

[0188] Those skilled in the art will understand that all or some of the steps of the methods, the functional modules / units of the systems and devices disclosed above can be implemented as software, firmware, hardware, and appropriate combinations thereof. In hardware embodiments, the division between the functional modules / units mentioned in the above description does not necessarily correspond to the division of physical components. For example, one physical component may have multiple functions, or one function or step may be executed in cooperation by several physical components. Some physical components or all physical components may be implemented as software executed by a processor such as a central processing unit, a digital signal processor, or a microprocessor, or as hardware, or as an integrated circuit such as an application specific integrated circuit. Such software may be arranged on a computer-readable medium that may include a computer storage medium (or non-transitory medium) and a communication medium (or transitory medium). As is well known to those skilled in the art, the term computer storage medium includes volatile and non-volatile, removable and non-removable media implemented by any method or technology for storing information such as computer-readable instructions, data structures, program modules, or other data. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store the desired information and can be accessed by a computer. Also, communication media generally includes computer-readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transmission mechanism, and is known to those skilled in the art to include any information delivery medium.

[0189] Exemplary embodiments are disclosed herein, and specific terms are used, but they are used only in a general exemplary sense and should be construed only in a general exemplary sense and not for purposes of limitation. In some examples, features, characteristics, and / or elements described in connection with a particular embodiment may be used alone or in combination with features, characteristics, and / or elements described in connection with other embodiments, unless otherwise specified, which will be apparent to those skilled in the art. Thus, those skilled in the art will understand that various changes can be made in various forms and details without departing from the scope of the present disclosure as set forth in the appended claims.

Claims

1. receiving an upstream optical signal; generating second upstream electrical signals in a plurality of lanes based on the upstream optical signal, wherein the second upstream electrical signals in the plurality of lanes respectively correspond to first upstream electrical signals in the plurality of lanes obtained by cross-dividing an initial upstream signal by an upstream transmitting end according to an upstream granularity; lane-aligning the second upstream electrical signals in the plurality of lanes according to the upstream granularity, and restoring the signals after alignment to obtain a target upstream signal. A data transmission method.

2. The step of lane-aligning the second upstream electrical signals in the plurality of lanes according to the upstream granularity includes: analyzing the second upstream electrical signal in each lane to determine an upstream alignment flag bit of the second upstream electrical signal in each lane; aligning the second upstream electrical signals in the plurality of lanes based on the upstream alignment flag bits of the second upstream electrical signals in each lane. The data transmission method according to Claim 1.

3. The step of analyzing the second upstream electrical signal in each lane to determine an upstream alignment flag bit of the second upstream electrical signal in each lane includes: determining a first upstream data block in the second upstream electrical signal for any one of the lanes, wherein the first upstream data block corresponds to a plurality of data fragments of a first upstream identifier in the initial upstream signal; determining the upstream alignment flag bit of the second upstream electrical signal based on the first upstream data block; in the first upstream identifier, the plurality of data fragments corresponding to the first upstream data blocks in the plurality of lanes are arranged in a mutually intersecting manner. The data transmission method according to claim 2.

4. The step of determining the upstream alignment flag bit of the second upstream electrical signal based on the first upstream data block is: including the step of using the first upstream data block as the upstream alignment flag bit The data transmission method according to claim 3.

5. The step of determining the upstream alignment flag bit of the second upstream electrical signal based on the first upstream data block is: including the step of combining the first upstream data blocks of two consecutive physical frames in a lane to obtain the upstream alignment flag bit The data transmission method according to claim 3.

6. The step of determining the upstream alignment flag bit of the second upstream electrical signal based on the first upstream data block is: including the step of extending the length of the first upstream data block to obtain the upstream alignment flag bit, wherein the length of the extended first upstream data block is equal to the length of the first upstream identifier The data transmission method according to claim 3.

7. The first upstream identifier is a delimiter in the upstream physical synchronization block PSBu, or the first upstream identifier is a bit stream formed by interleaving the delimiters in the PSBu The data transmission method according to any one of claims 3 to 6.

8. After lane-aligning the second upstream electrical signals in the plurality of lanes according to the upstream granularity, restoring them after alignment to obtain a target upstream signal, A step of determining a first accuracy rate for decoding a forward error correction FEC code in the target upward signal and a second accuracy rate for deframing a passive optical network capsule mode GEM frame, and When the first accuracy rate is lower than a first threshold and / or the second accuracy rate is lower than a second threshold, a step of resynchronizing data, and further includes The data transmission method according to any one of claims 1 to 6.

9. Based on the first upstream data block in the plurality of lanes, a step of determining a second upstream identifier corresponding to the first upstream identifier, and A step of determining a ratio of bits of a preamble before the second upstream identifier that are the same as a preset preamble, and When the ratio is lower than a third threshold, a step of re-determining the second upstream identifier, and further includes The data transmission method according to claim 3.

10. Based on the first upstream data block in the plurality of lanes, a step of determining a second upstream identifier corresponding to the first upstream identifier, and Based on the second upstream identifier, a step of determining whether an optical network unit for transmitting the upstream optical signal is abnormal, and further includes The data transmission method according to claim 3.

11. The step of generating a second upstream electrical signal in a plurality of lanes based on the upstream optical signal is Including the step of demodulating the upstream optical signal to obtain the second upstream electrical signal in the plurality of lanes The data transmission method according to any one of claims 1 to 6.

12. A step of cross-dividing an initial upstream signal according to an upstream granularity to obtain a first upstream electrical signal in a plurality of lanes, and Generating one upstream optical signal based on the first upstream electrical signal in the plurality of lanes; Transmitting the upstream optical signal; and A data transmission method. **Claim 13** The step of generating one upstream optical signal based on the first upstream electrical signal in the plurality of lanes includes: Modulating the first upstream electrical signal in the plurality of lanes to obtain the upstream optical signal. The data transmission method according to claim 12. **Claim 14** Receiving a downstream optical signal; Generating a second downstream electrical signal in a plurality of lanes based on the downstream optical signal, wherein the second downstream electrical signal in the plurality of lanes corresponds to the first downstream electrical signal in the plurality of lanes obtained by cross-dividing an initial downstream signal by a downstream transmitting end according to a downstream granularity; and Aligning the second downstream electrical signal in the plurality of lanes according to the downstream granularity, and restoring the aligned signal to obtain a target downstream signal. A data transmission method. **Claim 15** The step of aligning the second downstream electrical signal in the plurality of lanes according to the downstream granularity includes: Analyzing the second downstream electrical signal in each lane to determine a downstream alignment flag bit of the second downstream electrical signal in each lane; and Aligning the second downstream electrical signal in the plurality of lanes based on the downstream alignment flag bit of the second downstream electrical signal in each lane. The data transmission method according to claim 14. **Claim 16** The step of analyzing the second downstream electrical signal in each lane to determine a downstream alignment flag bit of the second downstream electrical signal in each lane includes: A step of determining a first downstream data block in the second downstream electrical signal for any one of the lanes, wherein the first downstream data block corresponds to a plurality of data fragments of a first downstream identifier in the initial downstream signal; Determining a downstream alignment flag bit of the second downstream electrical signal based on the first downstream data block; In the first downstream identifier, a plurality of data fragments corresponding to the first downstream data block in the plurality of lanes are arranged in a mutually intersecting manner. The data transmission method according to claim 15.

17. The step of determining a downstream alignment flag bit of the second downstream electrical signal based on the first downstream data block includes: Including the step of using the first downstream data block as the downstream alignment flag bit. The data transmission method according to claim 16.

18. The step of determining a downstream alignment flag bit of the second downstream electrical signal based on the first downstream data block includes: Combining the first downstream data blocks of two consecutive physical frames in a lane to obtain the downstream alignment flag bit. The data transmission method according to claim 16.

19. The step of determining a downstream alignment flag bit of the second downstream electrical signal based on the first downstream data block includes: Including the step of extending the length of the first downstream data block to obtain the downstream alignment flag bit. The length of the extended first downstream data block is equal to the length of the first downstream identifier. The data transmission method according to claim 16.

20. The first downstream identifier is the physical synchronization sequence Psync in the downstream physical synchronization block PSBd, or the first downstream identifier is a bit stream formed by interleaving Psync in the PSBd The data transmission method according to any one of claims 16 to 19.

21. After lane-aligning the second downstream electrical signals in the plurality of lanes according to the downstream granularity, restoring them after alignment to obtain a target downstream signal, determining a third accuracy rate for decoding the forward error correction FEC code in the target downstream signal and a fourth accuracy rate for deframing the passive optical network capsule mode GEM frame; when the third accuracy rate is lower than a fourth threshold and / or when the fourth accuracy rate is lower than a fifth threshold, further including the step of resynchronizing the data The data transmission method according to any one of claims 14 to 19.

22. The step of generating second downstream electrical signals in a plurality of lanes based on the downstream optical signal includes demodulating the downstream optical signal to obtain the second downstream electrical signals in the plurality of lanes The data transmission method according to any one of claims 14 to 19.

23. cross-dividing an initial downstream signal according to the downstream granularity to obtain first downstream electrical signals in a plurality of lanes; generating one downstream optical signal based on the first downstream electrical signals in the plurality of lanes; transmitting the downstream optical signal Data transmission method.

24. The step of generating one downstream optical signal based on the first downstream electrical signals in the plurality of lanes includes including the step of modulating the first downstream electrical signal in the plurality of lanes to obtain the downstream optical signal The data transmission method according to claim 23.

25. one or more processors; a memory storing one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors are caused to implement the data transmission method according to any one of claims 1 to 11 and / or the data transmission method according to claim 23 or 24; one or more I / O interfaces connected between the processor and the memory and configured to realize the exchange of information between the processor and the memory, comprising an optical line terminal OLT.

26. one or more processors; a memory storing one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors are caused to implement the data transmission method according to any one of claims 14 to 22 and / or the data transmission method according to claim 12 or 13; an optical network unit ONU.

27. a computer-readable medium storing a computer program, wherein when the program is executed by a processor, the processor is caused to implement the data transmission method according to any one of claims 1 to 24 Computer-readable medium.

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