WO2020063685A1

WO2020063685A1 - Optical network system, olt, signal transmission method and readable storage medium

Info

Publication number: WO2020063685A1
Application number: PCT/CN2019/107927
Authority: WO
Inventors: 杨巍; 杨波; 黄新刚
Original assignee: 中兴通讯股份有限公司
Priority date: 2018-09-25
Filing date: 2019-09-25
Publication date: 2020-04-02
Also published as: CN109067465A

Abstract

The disclosure provides an optical network system, an optical line terminal, a signal transmission method and a readable storage medium. The optical network system comprises an optical line terminal module, a main optical splitter and at least two optical network units; the main optical splitter is an M: N type optical splitter, and both M and N are greater than or equal to 2; the M end of the main optical splitter is connected with the optical line terminal module, and the N end of the main optical splitter is connected with the optical network system; and the optical line terminal module receives through M receivers uplink signals forwarded by the main optical splitter, and superposes uplink signals received by at least two receivers.

Description

Optical network system, OLT, signal transmission method, and readable storage medium

Technical field

The embodiments of the present disclosure relate to, but are not limited to, the field of optical communication, and in particular, to an optical network system, an OLT, a signal transmission method, and a readable storage medium.

Background technique

Since there are many users in the optical access field and multi-level optical splitting is used, power budget is a very important issue. As the user's bandwidth continues to increase and the signal rate continues to increase, the receiver's sensitivity will relatively decrease. If the transmit power is not increased, it will cause a problem of insufficient power budget. Directly increasing the transmitted optical power means a substantial increase in cost, which is not a good solution for cost-sensitive user-end equipment.

Summary of the Invention

An embodiment of the present disclosure provides an optical network system including an optical line terminal (OLT) component, a main optical splitter, and at least two optical network units (ONUs). The main beam splitter is an M: N type beam splitter, and M and N are both greater than or equal to two. The M end of the main optical splitter is connected to the OLT component, and the N end is connected to the ONU. The OLT component receives the uplink signals forwarded by the main optical splitter through M receivers, and superimposes the uplink signals received by at least two receivers.

An embodiment of the present disclosure further provides an OLT, which includes at least one receiver, and the OLT receives uplink signals received and superimposed by at least two receivers. The uplink signal is forwarded by the main optical splitter. The main optical splitter is an M: N type optical splitter, and M and N are both greater than or equal to 2, the M end is connected to the receiver, and the N end is connected to the ONU.

An embodiment of the present disclosure further provides a signal transmission method, which is applied to an optical network system according to the present disclosure. The signal transmission method includes: the ONU generates an uplink signal; and after the uplink signal passes through the main optical splitter, it is divided into M channels and sent to the receiver of the OLT in the OLT component, and the uplink received by at least two receivers The signals are superimposed.

An embodiment of the present disclosure further provides a computer storage medium on which one or more programs are stored, and the one or more programs can be executed by one or more processors to implement the steps of the signal transmission method according to the present disclosure. .

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of an optical splitter in the related art; FIG.

FIG. 2 is a schematic structural diagram of an optical network system according to an embodiment of the present disclosure; FIG.

FIG. 3 is a schematic diagram of a composition of an optical network system according to an embodiment of the present disclosure;

4 is a schematic structural diagram of a composition of a synchronous addition module according to an embodiment of the present disclosure;

FIG. 5 is a schematic composition diagram of an optical network system according to an embodiment of the present disclosure;

FIG. 6 is a schematic composition diagram of an optical network system according to an embodiment of the present disclosure; FIG.

FIG. 7 is a schematic composition diagram of an optical network system according to an embodiment of the present disclosure; and

FIG. 8 is a flowchart of a signal transmission method according to an embodiment of the present disclosure.

detailed description

In order to make the objectives, technical solutions, and advantages of the present disclosure more clear, the embodiments of the present disclosure will be further described in detail through specific implementations in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present disclosure and are not intended to limit the present disclosure.

Since there are many users in the optical access field and multi-level optical splitting is used, power budget is a very important issue. As the user's bandwidth continues to increase and the signal rate continues to increase, the receiver's sensitivity will relatively decrease. If the transmit power is not increased, it will cause a problem of insufficient power budget. Directly increasing the transmitted optical power means a substantial increase in cost, which is not a good solution for cost-sensitive user-end equipment. Most of the current passive optical network (PON) optical distribution networks (ODN) are 1: N splitters, as shown in Figure 1. For the upward direction (the direction from the right to the left in the figure), after passing this type of optical splitter, the optical power will be reduced to 1 / N, that is, the optical power will be reduced by 10log (N) dB, Energy is wasted. In order to increase the uplink power, usually adopting means such as increasing the transmit power at the transmitting end and adding an amplifier, but these solutions all rely on additional energy compensation and higher costs.

Example one

In order to improve the power budget of uplink signal transmission, this embodiment provides an optical network system. Referring to FIG. 2, the optical network system in this embodiment includes: an OLT component 21, a main optical splitter 22, and at least two ONUs 23. The main beam splitter 22 is an M: N type beam splitter, and M and N are both greater than or equal to two. The M end of the main optical splitter 22 is connected to the OLT component 21, and the N end is connected to the ONU 23. The OLT component 21 receives the uplink signals forwarded by the main optical splitter 22 through M receivers, and superimposes the uplink signals received by at least two receivers.

The optical splitter, also called an optical splitter, is one of the important passive components in an optical fiber link, and is an optical fiber tandem device with multiple input ends and multiple output ends. Optical splitters can be divided into two types: fused pull-cone type and planar waveguide type (PLC type) according to the principle of optical splitting. The main technical parameters of the optical splitter include loss, splitting ratio, and isolation. The insertion loss of the optical splitter refers to the dB (decibel) number of each output relative to the input optical loss. Its mathematical expression is: Ai = -10lgPouti / Pin, where Ai refers to the insertion loss of the i-th output port, and Pouti Is the optical power of the i-th output port, and Pin is the optical power value of the input end. The split ratio is defined as the output power ratio of the output ports of the splitter. In the system application, the appropriate splitting ratio can be determined according to the optical power required by the actual system optical node, or it can be directly distributed evenly. The splitting ratio of the beam splitter is related to the wavelength of the transmitted light. Isolation refers to the ability of an optical path of an optical splitter to isolate optical signals in other optical paths.

In this embodiment, the type of the main beam splitter 22 used is an M: N type, where M and N are both greater than or equal to two. The main optical splitter 22 includes two ends of M and N. The M terminal has M interfaces and the N terminal has N interfaces. The M terminal is located on the OLT side and is connected to the OLT component 21; the N terminal is located on the ONU 23 side and connected to the ONU 23. The uplink signal is sent from the ONU 23 in the form of an optical signal, and is sent to the M end through the N end of the main optical splitter 22. The M interfaces at the M end are connected to the M receivers in the OLT component 21, that is, the main optical splitter 22 divides the M uplink signals into M ports, and then transmits them to the receiver in the OLT component 21. In this embodiment, the M terminal has at least two interfaces. Compared with the case where there is only one port in the related technology, one light is changed to at least two lights, thereby theoretically increasing the uplink power to at least twice. That is, the uplink power budget is increased by at least 3 dB.

Optionally, in this embodiment, M and N may be equal. That is, the main optical splitter 22 may be an N: N optical splitter, and the number of optical paths of the two ports of M and N is the same. For example, N: N can be 2: 2, or 4: 4, 8: 8, and so on.

In an optical network system, the number of ONUs 23 is often more than one. When there are multiple ONUs 23, in some embodiments, the optical network system may further include a slave optical splitter. At least one port on the N end of the main optical splitter 22 and the ONU 23 can be connected through the secondary optical splitter. That is, the ONU 23 and the master optical splitter 22 can be connected through the slave optical splitter. In this embodiment, the number of slave beam splitters and the type of slave beam splitters are not limited. The type of the secondary beam splitter may be an X: Y type, where X and Y are both greater than or equal to 1. Referring to FIG. 3, FIG. 3 shows a schematic composition diagram of an optical network system having a slave optical splitter in this embodiment, and the slave optical splitter shown is a 1: N optical splitter. In addition, there may be multiple-stage slave beam splitters, and the slave beam splitters at all levels are connected in sequence, and finally connected to the master beam splitter 22.

In some embodiments, the OLT component 21 includes at least one OLT, and at least one receiver is disposed in the at least one OLT. When at least one OLT in the OLT component 21 is provided with two receivers, the uplink signals received by the two receivers are combined in the OLT. For this OLT, the power of the uplink signal it receives is twice as much as if it were received by only one receiver. The uplink signals are received through two receivers. There may be synchronization problems between different uplink signals. This is because different optical fibers are connected from the main optical splitter 22 to the OLT. The distance between different optical fibers and the OLT may be different. This difference results in a possible time difference between the uplink signals received by the two OLT receivers. In some embodiments, the OLT component 21 further includes a synchronous addition module 30. When superimposing the uplink signals received by at least two receivers, the synchronous addition module 30 is connected to a receiver corresponding to the uplink signals to be superimposed. To receive the uplink signal transmitted by the receiver and perform synchronous superposition. For the case where synchronous superposition is required, it may include a case where each receiver is located in one OLT, and a case where one receiver is located in one OLT, and other receivers are located outside the OLT and superimpose uplink signals.

In some embodiments, the synchronous addition module 30 includes a buffer 31 that matches the number of receivers, a delay calculation module 32, an adjustable delay module 33, and an analog addition module 34. The buffer 31 receives an uplink signal transmitted by each receiver and buffers it. The delay calculation module 32 performs delay calculation according to each uplink signal buffered in the buffer 31, and controls the time for the adjustable delay module 33 to align with each uplink signal based on the delay calculation result. After the time of each uplink signal is aligned, the uplink signal is superimposed by the analog addition module 34. Referring to FIG. 4, FIG. 4 shows a schematic composition structure of the synchronous addition module 30 in this embodiment. Since at least two optical fibers are connected from the optical splitter to the OLT, the distance between different optical fibers and the OLT may be slightly different, which may cause a time difference in the electrical signals received by the receivers of the OLT. If these two electrical signals are directly added, errors may result. Therefore, the two electrical signals need to be processed synchronously to delay one of the signals appropriately to ensure that the two signals are aligned in time before adding.

As shown in FIG. 4, the two analog electrical signals received by the receiver are first buffered by two buffers 31, and then the time difference between the two signals in the two buffers 31 is calculated by the delay calculation module 32. The delay calculation module 32 may obtain the time difference by calculating a cross-correlation of the two signals. After the delay calculation module 32 obtains the time difference, the two analog electrical signals are aligned in time by adjusting the delay of the adjustable delay module 33. The process of adjusting the delay can be implemented during the registration process of the ONU 23. In general, once the delay is determined that no special circumstances occur, there is no need to change the delay. After the delay adjustment is completed, the two analog electric signals are added to the OLT line card after being added by the analog addition module 34.

The OLT can detect the bit error condition of the uplink signal in real time. If the bit error rate is too high, the ONU 23 is disconnected and the registration process is restarted. The OLT can send a signal to cause the synchronous addition module 30 to recalculate the delay situation, and update the delay of the adjustable delay module 33 to align the two signals again.

In some embodiments, the OLT component 21 may include at least two OLTs. When the OLT component 21 includes at least two OLTs, at least one OLT is a master OLT, and at least one OLT different from the master OLT is a standby OLT. When the master OLT is not working, the standby OLT takes over the work of the master OLT. When the OLT component 21 includes at least two OLTs, one of the OLTs may be a normal working OLT, that is, the main OLT, and the other OLT may be a standby OLT of the normal working OLT. A signal connection may exist between the two OLTs, so that the configuration information and registration information between the two OLTs are consistent. When one OLT fails and cannot work normally, the other OLT replaces the OLT and works. The configuration of the primary OLT and the standby OLT and the ONU registration information can be completely the same. The standby OLT can copy the configuration of the primary OLT and the ONU registration information when the primary OLT is working. In addition, the primary OLT and the standby OLT are not fixed configuration methods. In some cases The lower active OLT can also be used as the standby OLT, and the standby OLT can also be used as the active OLT, that is, two OLTs can be active and standby each other.

This embodiment provides an optical network system including an optical line terminal OLT component, a main optical splitter, and at least two optical network units ONUs. The main beam splitter is an M: N-type beam splitter, and M and N are both greater than or equal to two. The M end of the main optical splitter is connected to the OLT component, and the N end is connected to the ONU. The OLT component receives the uplink signal forwarded by the main optical splitter through M receivers. In some implementation processes, the M: N type main optical splitter effectively avoids the power loss of the uplink signal, significantly improves the uplink power budget, and provides a wider range of application space for the optical network system.

Example two

This embodiment provides an optical network system. Please refer to FIG. 5, the ODN main optical splitter is a 2: 2 optical splitter, and

ports

1 and 2 are respectively connected to two receivers of one optical module of the OLT. The two receivers convert the two optical signals into two electric signals, and the two electric signals are synchronized and added inside the optical module, and then transmitted upward. In the figure, ONU1, ONU2, ONUn, ONUn + 1, ONUn + 2, ONU2n identify different ONUs.

As shown in FIG. 5, two receivers PD1 and PD2 are provided in the OLT module (OLT optical module). The transmitter DFB shares a fiber port with the receiver PD1 through a multiplexer and demultiplexer, and the receiver PD2 uses another fiber port. These two optical ports are connected to port 1 and port 2 of the 2: 2 splitter, respectively.

For the downlink, the optical signal transmitted by the transmitter DFB enters the main optical splitter at 2: 2 through port 1, and then the optical signal is transmitted equally down through port 3 and port 4, and then reaches each ONU through the optical splitter and fiber. The figure shows the use of two 1: N splitters. The actual situation is not limited to this. More than two slave splitters and / or multi-stage slave splitters can be used.

For the uplink, the ONU transmits an upstream burst signal, passes through the optical fiber and each slave splitter, and then reaches the master splitter, for example, it reaches port 4 of the master splitter, and then splits out from

ports

1 and 2 to enter the OLT optical module. In the related art, the OLT optical module does not include port 2 and receiver PD2, so half of the upstream optical power is wasted. The technical solution of the present disclosure uses the receivers PD1 and PD2 to receive two optical signals at the same time, and converts them into analog electric signals. The two electrical signals are added on the electrical domain after synchronization (for example, an analog electrical adder can be used), and the analog electrical signals are converted into digital electrical signals after the addition, and uploaded to the OLT line card. In this way, the uplink received optical signal power can be doubled, that is, the uplink power budget is increased by 3dB.

Example three

This embodiment provides an optical network system. Referring to FIG. 6, the main optical splitter uses a 2: 2 optical splitter, port 1 is connected to an OLT component (OLT optical module), and port 2 is connected to a dedicated receiver PD2 on the OLT line card. There is a dedicated electrical channel between the OLT optical module and the OLT line card, and the analog signal converted by the receiver PD2 is transmitted to the OLT optical module. In the OLT optical module, the analog signal converted by the receiver PD2 and the analog electric signal converted by the receiver PD1 are synchronized and added, and then converted into a digital electric signal and transmitted to the OLT line card.

As shown in FIG. 6, compared to the conventional optical module, the OLT optical module in this embodiment adds an analog electrical channel for receiving an analog electrical signal converted by the receiver PD2 on the OLT line card.

For the downlink, the downlink optical signal transmitted by the OLT optical module enters the main optical splitter at 2: 2 through port 1, and then the optical signal is transmitted downward equally through port 3 and port 4, and then reaches each ONU through the optical splitter and fiber. The figure shows the use of two 1: N splitters. The actual situation is not limited to this. More than two slave splitters and / or multi-stage slave splitters can be used.

ports

1 and 2 to enter the OLT optical module and Dedicated receiver PD2 for OLT line cards. The receiver PD2 receives the optical signal and converts it into an analog electrical signal, and inputs the analog electrical signal to the OLT optical module. In the OLT optical module, the receiver PD1 receives the optical signal and converts it into an analog electrical signal, synchronizes and adds the analog electrical signal with the analog electrical signal from PD2, and then converts the digital electrical signal to the OLT line card and uploads it. In this way, the uplink received optical signal power can be doubled, that is, the uplink power budget is increased by 3dB.

This embodiment also provides an OLT. 5 and FIG. 6, the OLT includes at least one receiver, and the OLT receives the uplink signals received by the at least two receivers, and superimposes the uplink signals. The uplink signal is forwarded by the main optical splitter, which is an M: N type optical splitter, and M and N are both greater than or equal to 2. The M end of the main optical splitter is connected to each receiver, and the N end is connected to the ONU. In this embodiment, the OLT includes at least one receiver. As shown in FIG. 5, the OLT includes two receivers. As shown in FIG. 6, the OLT includes one receiver, and the other receivers may be receivers on the OLT line card. , Or a receiver on another OLT. That is, for an OLT, among at least two receivers corresponding to the uplink signals received by the OLT, at least one receiver is set in the OLT, and the other receivers may be receivers set in the OLT. A receiver outside the OLT can be provided.

In some embodiments, the OLT may include a synchronous addition module 30. The uplink signals transmitted by the at least two receivers are received by the synchronous addition module 30 and superimposed, and the synchronous addition module 30 is connected to the at least two receivers.

In some embodiments, the synchronous addition module 30 includes a buffer 31 that matches the number of receivers, a delay calculation module 32, an adjustable delay module 33, and an analog addition module 34. The buffer 31 receives an uplink signal transmitted by each receiver and buffers it. The delay calculation module 32 performs delay calculation according to each uplink signal buffered in the buffer 31, and controls the time for the adjustable delay module 33 to align with each uplink signal based on the delay calculation result. After the time of each uplink signal is aligned, the uplink signal is superimposed by the analog addition module 34.

Embodiment 4

This embodiment provides an optical network system. Referring to FIG. 7, the ODN main optical splitter is a 2: 2 optical splitter. Port 1 is connected to OLT1, and port 2 is connected to OLT2. OLT1 is the primary OLT, and OLT2 is the standby OLT.

When OLT1 is the main OLT and OLT2 is the standby OLT, OLT1 works and OLT2 is on standby.

For the downlink, the downlink signal enters the main optical splitter through port 1, and then the optical signal is transmitted equally down through port 3 and port 4, and reaches each ONU through the slave optical splitter and fiber. The figure shows the use of two 1: N splitters. The actual situation is not limited to this. More than two slave splitters and / or multi-stage slave splitters can be used.

For the uplink, the ONU transmits an uplink burst signal, passes through the optical fiber and each slave splitter, and then reaches the master splitter, for example, it reaches port 4 of the master splitter, and then splits out from

ports

1 and 2 to enter OLT1 and OLT2, respectively. OLT1 receives the uplink burst signal and forwards it upward, and OLT2 receives the uplink burst signal but does not process it. There is a signal connection between OTL1 and OLT2. OLT2 completely replicates the configuration of OLT1 and ONU registration. If OLT1 fails and cannot work normally, OLT1 sends a signal to OLT2, OLT2 starts to take over OLT1, restarts the registration process and updates the ONU registration information (for example, ONU distance, etc.). OLT1 and OLT2 can be swapped, that is, OLT1 and OLT2 can be active and standby for each other.

The main optical splitter in this embodiment is not limited to using a 2: 2 optical splitter, and an N: N optical splitter may also be used. In addition, more than one OLT may be used as a backup, and this embodiment may be performed in the same manner as in the second or third embodiment. combination. When N: N splitter is used, multiple OLTs can also connect multiple optical fibers.

Example 5

Referring to FIG. 8, FIG. 8 is a flowchart of a signal transmission method according to an embodiment of the present disclosure. The method can be applied to an optical network system of each embodiment of the present disclosure, and includes steps S801 and S802.

In step S801, the ONU generates an uplink signal.

In step S802, after the uplink signal passes through the main optical splitter, it is divided into M channels and sent to the receiver of the OLT in the OLT component, and the uplink signals received by at least two receivers are superimposed.

The optical network system applied in this embodiment is as described in the foregoing embodiments, and is not repeated here.

Example Six

This embodiment provides a computer-readable storage medium including the method implemented in any method or technology for storing information such as computer-readable instructions, data structures, computer program modules, or other data. Volatile or non-volatile, removable or non-removable media. Computer-readable storage media include, but are not limited to, RAM (Random Access Memory), ROM (Read-Only Memory, Read-Only Memory), EEPROM (Electrically Erasable, Programmable, Read-Only Memory, and Erasable Programmable Read-Only Memory) ), Flash memory or other memory technology, CD-ROM (Compact Disc Read-Only Memory), digital versatile disk (DVD) or other optical disk storage, magnetic box, magnetic tape, disk storage or other magnetic storage devices, Or any other medium that can be used to store desired information and can be accessed by a computer.

The computer-readable storage medium in this embodiment may store one or more computer programs, and the stored one or more computer programs may be executed by a processor to implement the steps of the signal transmission method in the foregoing embodiments.

This embodiment also provides a computer program (or computer software), which can be distributed on a computer-readable medium and executed by a computable device to implement the steps of the signal transmission method in the foregoing embodiments. In some cases, the steps shown or described may be performed in an order different from that described in the above embodiments.

This embodiment also provides a computer program product including a computer-readable device, where the computer-readable device stores the computer program as shown above. The computer-readable device in this embodiment may include a computer-readable storage medium as shown above.

It can be seen that those skilled in the art should understand that all or some of the steps, systems, and functional modules / units in the devices disclosed in the above methods can be implemented as software (can be implemented by computer program code executable by a computing device ), Firmware, hardware, and appropriate combinations. In the hardware implementation, 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 composed of several physical The components execute cooperatively. Some or all physical components can be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit .

The above content is a further detailed description of the embodiments of the present disclosure in combination with specific implementation manners, and it cannot be considered that the specific implementation of the present disclosure is limited to these descriptions. For those of ordinary skill in the technical field to which the present disclosure belongs, without departing from the concept of the present disclosure, several simple deductions or replacements can be made, which should all be regarded as falling within the protection scope of the present disclosure.

Claims

An optical network system includes an optical line terminal OLT component (21), a main optical splitter (22), and at least two optical network units ONU (23),

The main optical splitter (22) is an M: N type optical splitter, and M and N are both greater than or equal to 2. The M end of the main optical splitter (22) is connected to the OLT component (21), and the N end is connected to the OLT component (21). The ONU (23) is connected;

The OLT component (21) receives the uplink signals forwarded by the main optical splitter (22) through M receivers, and superimposes the uplink signals received by at least two receivers.
The optical network system according to claim 1, further comprising a slave optical splitter, through which at least one port of the N-end of the master optical splitter (22) is connected to the ONU (23).
The optical network system according to claim 2, wherein the type of the slave optical splitter is an X: Y type, wherein X and Y are both greater than or equal to 1.
The optical network system according to claim 1, wherein M and N are equal.
The optical network system according to claim 1, wherein the OLT component (21) comprises at least one OLT, and at least one receiver is disposed in the at least one OLT.
The optical network system according to any one of claims 1-5, wherein the OLT component (21) comprises a synchronous addition module (30), and performs an uplink signal received by the at least two receivers. During the superimposition, the synchronous addition module (30) is connected to a receiver corresponding to the uplink signal to be superimposed, so as to receive the uplink signal transmitted by the receiver and perform synchronous superposition.
The optical network system according to claim 6, wherein the synchronous addition module (30) comprises a buffer (31), a delay calculation module (32), and an adjustable delay module that match the number of the receivers. (33) and the analog addition module (34),

The buffer (31) receives and buffers uplink signals transmitted by each receiver,

The delay calculation module (32) performs delay calculation according to each uplink signal buffered in the buffer (31), and controls the adjustable delay module (33) to align each uplink signal based on the delay calculation result. time,

After the time of each uplink signal is aligned, the uplink signal is superimposed by the analog addition module (34).
The optical network system according to any one of claims 1-5, wherein the OLT component (21) includes at least two OLTs.
The optical network system according to claim 8, wherein at least one OLT among the at least two OLTs is a master OLT, and at least one OLT different from the master OLT is a standby OLT,

When the master OLT is not working, the standby OLT takes over the work of the master OLT.
An optical line terminal OLT includes at least one receiver, the OLT receives uplink signals received by at least two receivers, and superimposes the uplink signals,

The uplink signal is forwarded by a main optical splitter (22). The main optical splitter (22) is an M: N type optical splitter, and M and N are both greater than or equal to 2. The M end and the at least two receive Machine is connected, N terminal is connected to ONU (23).
The OLT according to claim 10, further comprising a synchronous addition module (30),

The uplink signals transmitted by the at least two receivers are received by the synchronous addition module (30) and superimposed, and the synchronous addition module (30) is connected to the at least two receivers.
The OLT according to claim 11, wherein the synchronous addition module (30) comprises a buffer (31), a delay calculation module (32), and an adjustable delay module (33) that match the number of the receivers. ) And the analog addition module (34),

The buffer (31) receives and buffers uplink signals transmitted by each receiver,

The delay calculation module (32) performs delay calculation according to each uplink signal buffered in the buffer (31), and controls the adjustable delay module (33) to align each uplink signal based on the delay calculation result. time,

After the time of each uplink signal is aligned, the uplink signal is superimposed by the analog addition module (34).
A signal transmission method applied to the optical network system according to any one of claims 1-9, wherein the signal transmission method includes:

The ONU (23) generates an uplink signal; and

After the uplink signal passes through the main optical splitter (22), it is divided into M channels and sent to the receiver of the OLT in the OLT component (21), and the uplink signals received by at least two receivers are superimposed. .
A computer-readable storage medium having stored thereon one or more computer programs, the one or more computer programs being executable by one or more processors to implement the steps of the signal transmission method according to claim 13 .