Data transmission system and method based on wavelength division multiplexing passive optical network

Abstract

The embodiment of the present application discloses a kind of data transmission system and method based on wavelength division multiplexing passive optical network.The complete independent OLT port and GPON OLT module of each service type are configured in the optical line terminal of data transmission system to transmit corresponding service data at specified upstream and downstream wavelengths, realize the isolation of physical port level, eliminate the risk of configuration cross or misoperation caused by service data sharing OLT port, ensure the clarity of operation and management and the definiteness of service boundary.The multiplexing transmission of multiple wavelengths in the same optical fiber is realized by the combining and splitting wave filter and ODN arranged in the data transmission system.The upstream and downstream signals corresponding to different wavelengths in ONU are received by setting different BOSA, and only the corresponding wavelength signal can be received and transmitted by each user terminal connected with BOSA, so as to realize data physical isolation without significantly increasing the cost of network infrastructure construction, effectively eliminating the risk of cross-department data access or monitoring.

Description

Technical Field

[0001] This application relates to the field of communications, and more particularly to a data transmission system and method based on wavelength division multiplexing passive optical networks. Background Technology

[0002] With the continuous development of communication technology and people's growing network needs, the construction of communication equipment and networks based on optical communication has become the main direction of network infrastructure construction.

[0003] PON (Passive Optical Network), as a basic network architecture based on optical communication, typically consists of an optical line terminal (OLT) installed at a central control station, an optical distribution network (ODN), and a number of optical network units (ONUs) installed at user sites.

[0004] The inventors studied the operational details of existing PON-based optical communication networks in various application scenarios and found that the confidentiality requirements of different service data during transmission vary within the same application scenario. Existing PON-based optical communication networks use gray light (uplink and downlink signals use different wavelengths and are not wavelength division multiplexed) as the data transmission carrier, meaning that data from different business departments can only share a single signal transmission link for transmission. This poses a risk that different service data can be viewed across departments during transmission. To achieve physical isolation of data transmission between different business departments, multiple optical communication networks need to be configured for data transmission between different business departments, resulting in high network infrastructure construction costs and low utilization of data transmission capacity. Summary of the Invention

[0005] This invention provides a data transmission system and method based on wavelength division multiplexing (WDM) passive optical networks. It solves the problems of existing PON-based optical communication networks, which use gray light as the data transmission carrier. This means that data from different business departments can only share a single signal transmission link within a single optical communication network, posing a risk of cross-departmental access to different business data during transmission. Furthermore, achieving physical isolation of data transmission between different business departments requires configuring multiple optical communication networks, resulting in high network infrastructure construction costs and low data transmission capacity utilization.

[0006] In a first aspect, embodiments of the present invention provide a data transmission system based on a wavelength division multiplexing passive optical network, the data transmission system comprising:

[0007] The optical line terminal includes multiple GPON OLT modules. Each GPON OLT module is used to transmit downlink optical signals and receive uplink optical signals corresponding to a certain service type. The uplink and downlink optical signals of different service types each correspond to a unique wavelength.

[0008] The first multiplexer / demultiplexer includes multiple demultiplexing interfaces and one multiplexing interface. Each demultiplexing interface is connected to one of the GPON OLT modules, and the multiplexing interface is connected to a first interface of the ODN. The first multiplexer / demultiplexer is used to combine multiple downlink optical signals into a first mixed optical signal and transmit the first mixed optical signal to the ODN; and to separate a second mixed optical signal into uplink optical signals corresponding to each of the service types and transmit the uplink optical signals to the corresponding GPON OLT modules.

[0009] The ODN includes multiple second interfaces, each of which is connected to an ONU. The ODN is used to transmit the first mixed optical signal to each ONU, and to combine each third mixed optical signal into the second mixed optical signal, and then transmit the second mixed optical signal to the first multiplexer / demultiplexer.

[0010] The ONU is configured to separate downlink optical signals corresponding to at least one of the service types from the first mixed optical signal, convert the downlink optical signals into a first electrical signal and transmit them to the corresponding user terminal; and to convert the second electrical signal corresponding to at least one of the service types uploaded by the user terminal into an uplink optical signal, and then synthesize the uplink optical signal into the third mixed optical signal and transmit it to the ODN.

[0011] Each of the ONUs includes a first sub-network unit and a second sub-network unit;

[0012] When the first sub-network unit is used for signal transmission, it separates downlink optical signals corresponding to at least one of the service types from the first mixed optical signal, converts the downlink optical signals into a first electrical signal and transmits it to the corresponding user terminal; and it is used to convert the second electrical signal corresponding to at least one of the service types uploaded by the user terminal into an uplink optical signal, and then synthesizes the uplink optical signals into the third mixed optical signal and transmits it to the ODN.

[0013] When the second sub-network unit is used for signal transmission, it separates downlink optical signals corresponding to at least one of the service types from the first mixed optical signal, converts the downlink optical signals into first electrical signals and transmits them to the corresponding user terminal; and it is used to convert the second electrical signals corresponding to at least one of the service types uploaded by the user terminal into uplink optical signals, and then synthesizes the uplink optical signals into the third mixed optical signal and transmits them to the ODN.

[0014] Only one of the first sub-network unit and the second sub-network unit can transmit signals at any given time.

[0015] The first sub-network unit includes multiple first BOSAs, and the second sub-network unit includes multiple second BOSAs. The multiple first BOSAs are used to transmit optical signals corresponding to different service types, and the multiple second BOSAs are used to transmit optical signals corresponding to different service types.

[0016] The ONU includes an upper housing, a lower housing, and multiple circuit boards, which are disposed within the cavity formed by the upper and lower housings. Each circuit board is used to carry a first BOSA and a second BOSA corresponding to the same service type, and the service types corresponding to each circuit board are different.

[0017] The multiple circuit boards are stacked together.

[0018] The ONU includes a main circuit board and multiple slave circuit boards. The main circuit board includes multiple main interfaces, and each slave circuit board includes a slave interface. Each slave circuit board is used to carry BOSAs corresponding to different service types and is connected to the main circuit board through the slave interface and the main interface.

[0019] The number of service types is three, and the wavelengths of the uplink optical signals corresponding to the three service types are 1271nm, 1291nm and 1311nm, respectively, and the wavelengths of the downlink optical signals corresponding to the three service types are 1331nm, 1351nm and 1371nm, respectively.

[0020] The first multiplexer / demultiplexer includes three demultiplexing interfaces. The first multiplexer / demultiplexer is used to combine the downlink optical signals sent by the three GPON OLT modules into the first mixed optical signal, and to separate the second mixed optical signal into uplink optical signals corresponding to the three service types, and to transmit the three uplink optical signals to the corresponding GPON OLT receiving interfaces respectively.

[0021] Each ONU includes a second multiplexer / demultiplexer, which is used to separate downlink optical signals corresponding to at least one of the service types from the first mixed optical signal and transmit the downlink optical signals to the corresponding BOSA; and to combine the uplink optical signals transmitted by the BOSA into the third mixed optical signal.

[0022] Secondly, embodiments of the present invention provide a data transmission method based on a wavelength division multiplexing passive optical network. This data transmission method is applicable to the data transmission system based on a wavelength division multiplexing passive optical network as described in any of the preceding claims, and includes:

[0023] Each GPON OLT module of the optical line terminal sends a downlink optical signal corresponding to a service type to the demultiplexing interface of a first multiplexer / demultiplexer. The first multiplexer / demultiplexer combines multiple downlink optical signals into a first mixed optical signal and transmits the first mixed optical signal to the ODN. The ODN transmits the first mixed optical signal to multiple ONUs. The ONUs separate downlink optical signals corresponding to at least one service type from the first mixed optical signal, convert the downlink optical signals into a first electrical signal, and transmit it to the corresponding user terminal.

[0024] The ONU converts the second electrical signal, which corresponds to at least one of the service types, uploaded by the user terminal into an uplink optical signal, then combines the uplink optical signal into the third hybrid optical signal and transmits it to the ODN. The ODN combines each of the third hybrid optical signals into the second hybrid optical signal and transmits the second hybrid optical signal to the first multiplexer / demultiplexer. The first multiplexer / demultiplexer separates the second hybrid optical signal into uplink optical signals corresponding to each of the service types and transmits the uplink optical signals to the corresponding GPON OLT modules. Each GPON OLT module receives the corresponding uplink optical signal.

[0025] In summary, by configuring completely independent OLT ports and GPON OLT modules for each service type in the optical line terminal of the data transmission system to transmit corresponding service data at specified uplink and downlink wavelengths, physical port-level isolation is achieved. This eliminates the risks of configuration cross-contamination or misoperation caused by service data sharing OLT ports, ensuring clarity of operation and maintenance management and clear service boundaries. The multiplexers / demultiplexers and ODNs configured in the data transmission system accordingly enable multiplexed transmission of multiple wavelengths within the same optical fiber. For uplink and downlink signals corresponding to different wavelengths in the ONU, different BOSAs are configured to receive only the uplink and downlink optical signals of the corresponding service type. Each user terminal connected to the BOSA can only transmit and receive signals of the corresponding wavelength. This achieves physical data isolation without significantly increasing network infrastructure construction costs, effectively eliminating the risks of cross-departmental data access or eavesdropping. Attached Figure Description

[0026] Figure 1 This is an overall architecture diagram of a data transmission system based on wavelength division multiplexing (WDM) passive optical network provided in an embodiment of the present invention.

[0027] Figure 2 This is a three-dimensional structural diagram of an ONU in a passive optical network data transmission system based on wavelength division multiplexing, provided in an embodiment of this application.

[0028] Figure 3 This is a three-dimensional structural diagram of an ONU in a data transmission system based on wavelength division multiplexing (WDM) provided in an embodiment of this application.

[0029] Figure 4 An exploded view of an ONU in a data transmission system based on wavelength division multiplexing (WDM) passive optical network provided in an embodiment of this application.

[0030] Figure 5 for Figure 4 A magnified view of a portion of point A in the middle.

[0031] Figure 6 This is a schematic diagram of the structure of an ONU in a data transmission system based on wavelength division multiplexing (WDM) of a passive optical network, as provided in an embodiment of this application.

[0032] Figure 7 A flowchart illustrating the data transmission method of a passive optical network based on wavelength division multiplexing provided in this application embodiment. Detailed Implementation

[0033] The following description and accompanying drawings fully illustrate specific embodiments of this application to enable those skilled in the art to practice them. The embodiments represent only possible variations. Individual components and functions are optional unless explicitly required, and the order of operation may vary. Parts and features of some embodiments may be included in or replace parts and features of other embodiments. The scope of embodiments of this application includes the entire scope of the claims and all available equivalents of the claims. In this document, each embodiment may be referred to individually or collectively by the term "invention," which is merely for convenience and is not intended to automatically limit the scope of the application to any single invention or inventive concept if more than one invention is disclosed. Relational terms such as "first" and "second" are used herein only to distinguish one entity or operation from another, without requiring or implying any actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed. The various embodiments in this document are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the structures, products, etc., disclosed in the embodiments, since they correspond to the disclosed parts, the descriptions are relatively simple; relevant details can be found in the method section.

[0034] As a basic network architecture based on optical communication, PON typically consists of an optical line terminal installed at a central control station and a number of ONUs installed at user sites.

[0035] The inventors, through research into the operational details of existing PON-based optical communication networks in various application scenarios, discovered that the confidentiality requirements for different service data during transmission vary within the same application scenario. Existing PON-based optical communication networks pose a risk of unauthorized access to the transmission of different service data by unrelated business departments. Analysis of the underlying reasons for this risk reveals that existing PON-based optical communication networks use gray light (uplink and downlink signals use different wavelengths without wavelength division multiplexing) as the data transmission carrier. This means that data from different business departments can only share a single signal transmission link within a single optical communication network, creating a risk of cross-departmental access to different service data during transmission. Furthermore, achieving physical isolation of data transmission between different business departments requires configuring multiple optical communication networks for data transmission, resulting in high network infrastructure construction costs and low utilization of data transmission capacity.

[0036] Based on the analysis of the aforementioned data security phenomena and their technical causes, the inventors further propose a data transmission system and method based on wavelength division multiplexing (WDM) passive optical networks. By configuring completely independent OLT ports and GPON OLT modules for each service type in the optical line terminal of the data transmission system, corresponding service data is transmitted using specified uplink and downlink wavelengths. This achieves physical port-level isolation, eliminating the risks of configuration cross-contamination or misoperation caused by service data sharing OLT ports, and ensuring clarity in operation and maintenance management and the explicit definition of service boundaries. The multiplexers / demultiplexers and ODNs set up in the data transmission system correspondingly realize the multiplexing and transmission of multiple wavelengths in the same optical fiber. In the ONU, uplink and downlink signals corresponding to different wavelengths are configured so that different BOSAs only receive uplink and downlink optical signals of the corresponding service type. Each user terminal connected to the BOSA can only transmit and receive signals of the corresponding wavelength, thereby achieving physical data isolation without significantly increasing network infrastructure construction costs and effectively eliminating the risks of cross-departmental data access or eavesdropping.

[0037] Please refer to Figure 1 This is an overall architecture diagram of a data transmission system based on wavelength division multiplexing passive optical network provided in an embodiment of the present invention, as shown below. Figure 1 As shown, the data transmission system includes:

[0038] Optical line terminal 20 includes multiple GPON OLT modules. Each GPON OLT module is used to transmit downlink optical signals and receive uplink optical signals corresponding to a certain service type. The uplink and downlink optical signals of different service types each correspond to a unique wavelength.

[0039] The first multiplexer / demultiplexer 211 includes multiple demultiplexing interfaces and one multiplexing interface. Each demultiplexing interface is connected to a GPON OLT module, and the multiplexing interface is connected to a first interface of the ODN 40. The first multiplexer / demultiplexer 211 is used to combine multiple downlink optical signals into a first mixed optical signal and transmit the first mixed optical signal to the ODN 40; and to separate a second mixed optical signal into uplink optical signals corresponding to each service type and transmit the uplink optical signals to the corresponding GPON OLT module.

[0040] ODN 40 includes multiple second interfaces, each of which is connected to ONU 10. ODN 40 is used to transmit a first mixed optical signal to each ONU 10, and to transmit the second mixed optical signal to the first multiplexer / demultiplexer 211 after combining each third mixed optical signal into a second mixed optical signal.

[0041] ONU 10 is used to separate downlink optical signals corresponding to at least one service type from a first mixed optical signal, convert the downlink optical signals into a first electrical signal and transmit them to the corresponding user terminal; and is used to convert the second electrical signal corresponding to at least one service type uploaded by the user terminal into an uplink optical signal, and then combine the uplink optical signals into a third mixed optical signal and transmit it to ODN 40.

[0042] In this embodiment, multiple GPON OLT modules are configured in the optical line terminal of the data transmission system. Each GPON OLT module is used to transmit the uplink and downlink optical signals required for data transmission corresponding to a specific service type. Each GPON OLT module has an independent interface, and additional multiplexers / demultiplexers and ODNs are configured. The user terminal, which is directly responsible for processing the data corresponding to the service type, connects only to the ONU and uses the corresponding uplink and downlink optical signals for data transmission. The user terminal can only transmit data related to the corresponding service type through a set of uplink and downlink optical signals within the optical communication network. Data related to different service types cannot be cross-accessed between the ONU 10 and the optical line terminal 20. This ensures physical isolation of data transmission between different service types with lower network infrastructure construction costs and high utilization of data transmission capabilities, eliminating the risk of unrelated business departments viewing the transmission of different service data.

[0043] In one alternative implementation, such as Figure 1 As shown, each ONU 10 includes a first sub-network unit and a second sub-network unit. When transmitting signals, the first sub-network unit separates a downlink optical signal corresponding to at least one service type from a first mixed optical signal, converts the downlink optical signal into a first electrical signal, and transmits it to the corresponding user terminal. It also converts a second electrical signal corresponding to at least one service type uploaded by the user terminal into an uplink optical signal, then combines the uplink optical signals into a third mixed optical signal and transmits it to the ODN 40. Similarly, when transmitting signals, the second sub-network unit separates a downlink optical signal corresponding to at least one service type from the first mixed optical signal, converts the downlink optical signal into a first electrical signal, and transmits it to the corresponding user terminal. It also converts a second electrical signal corresponding to at least one service type uploaded by the user terminal into an uplink optical signal, then combines the uplink optical signals into a third mixed optical signal and transmits it to the ODN 40. Only one of the first and second sub-network units transmits signals at any given time.

[0044] Corresponding to Figure 1In the ONU 10 shown, there is a set of internal architecture hardware represented by solid lines and a set of internal architecture hardware represented by dashed lines. The two sets of internal architecture hardware correspond to the first sub-network unit and the second sub-network unit, respectively. Only one of the first sub-network unit and the second sub-network unit can transmit signals at any given time. This means that the first sub-network unit and the second sub-network unit are mutually backups. When the hardware corresponding to a service type in the ONU needs to be suspended due to failure or routine inspection, it can be seamlessly switched to the backup sub-network unit to maintain the normal operation of the entire data transmission system. The first sub-network unit and the second sub-network unit switch the connection status through a switch, and the sub-network unit connected to the signal transmission link performs signal transmission accordingly.

[0045] In another alternative implementation, such as Figure 1 As shown, the first sub-network unit includes multiple first BOSAs (Bi-Directional Optical Sub-Assembly), and the second sub-network unit includes multiple second BOSAs. The multiple first BOSAs are used to transmit optical signals corresponding to different service types; the multiple second BOSAs are also used to transmit optical signals corresponding to different service types. The first and second BOSAs can be considered as corresponding to the same bi-directional optical sub-assembly. Each first BOSA and each second BOSA is used to transmit the optical signal required for data transmission corresponding to a specific service type. When the first sub-network unit transmits signals, the multiple first BOSAs work together to transmit optical signals of various wavelengths. When the second sub-network unit transmits signals, the multiple second BOSAs work together to transmit optical signals of various wavelengths. The first and second BOSAs are only used to distinguish that the multiple BOSAs are located in different sub-network units, supporting different sub-network units to independently transmit optical signals.

[0046] In another alternative implementation, please combine Figures 2-5 As shown in the figure, the ONU 10 includes an upper housing 11, a lower housing 12, and multiple circuit boards 14. The side of the ONU 10 may also include multiple interfaces 13. The multiple circuit boards 14 are disposed within the cavity formed by the upper housing 11 and the lower housing 12. Each circuit board 14 is used to carry a first BOSA 141 and a second BOSA 142 corresponding to the same service type, and each circuit board 14 corresponds to a different service type. Within the cavity formed by the upper housing 11 and the lower housing 12, the multiple circuit boards 14 are stacked. If there are three service types, the arrangement is as follows: Figure 4As shown, the three-layer circuit board 14 is stacked. This arrangement of multiple circuit boards 14 within the cavity facilitates assembly and allows for centralized and rapid heat dissipation. Due to the connection design within the data transmission system, the multiple interfaces 13 only support data transmission for their corresponding service types. In practical implementation, interfaces 13 corresponding to different service types can be distinguished by different colors and / or patterns. This facilitates the deployment of the data transmission system in specific application scenarios, allowing user terminals from different business departments to quickly connect to the corresponding interfaces.

[0047] In yet another alternative implementation, such as Figure 6 As shown, the ONU 10 includes a main circuit board 15 and multiple slave circuit boards 16. The main circuit board 15 includes multiple main interfaces, and each slave circuit board 16 includes a slave interface. Each slave circuit board 16 is used to carry BOSAs corresponding to different service types and is connected to the main circuit board 15 through slave and main interfaces. Each slave circuit board 16 corresponds to one service type and carries the corresponding BOSA. Installation is performed via a plug-in interface, which effectively improves installation efficiency. When hardware failure occurs for some service types, maintenance costs are low and maintenance efficiency is high. Each slave circuit board 16 also has multiple data interfaces. In the case where a slave circuit board 16 has two BOSAs that act as primary and backup for each other, each slave circuit board 16 has four FE interfaces, two RS232 interfaces, and two RS485 interfaces. Figure 6 Each circuit board 16, viewed from above, displays two FE interfaces, one RS232 interface, and one RS485 interface as interfaces corresponding to one of the sub-network units. When the two sub-network units, which are mutually exclusive, switch, a switching chip connects the sub-network system currently transmitting data to the corresponding interfaces. Both the RS232 and RS485 interfaces correspond to uplink and downlink lines. A logic switch determines the currently used interface type, and the other end of the logic switch connects to the relevant interface of the ONU 10 CPU via the same uplink and downlink lines.

[0048] In another alternative implementation, such as Figure 1As shown, there are three service types, with uplink optical signal wavelengths of 1271nm, 1291nm, and 1311nm respectively, and downlink optical signal wavelengths of 1331nm, 1351nm, and 1371nm respectively. Specifically, for the first service type, the uplink optical signal wavelength is 1271nm and the downlink optical signal wavelength is 1331nm; for the second service type, the uplink optical signal wavelength is 1291nm and the downlink optical signal wavelength is 1351nm; and for the third service type, the uplink optical signal wavelength is 1311nm and the downlink optical signal wavelength is 1357nm. The hardware for transmitting optical signals at these wavelengths is relatively mature. Using these wavelengths to implement the wavelength division multiplexing-based passive optical network data transmission system in this embodiment can effectively control equipment production costs and reduce users' investment in network infrastructure construction.

[0049] In another alternative implementation, corresponding to the three service types, the first multiplexer / demultiplexer 211 includes three demultiplexing interfaces. The first multiplexer / demultiplexer 211 is used to combine the downlink optical signals sent by the three GPON OLT modules into a first mixed optical signal, and to separate the second mixed optical signal into uplink optical signals corresponding to the three service types, and to transmit the three uplink optical signals to the receiving interfaces of the corresponding GPON OLT respectively.

[0050] In another alternative implementation, each ONU 10 includes a second multiplexer / demultiplexer 17, which is used to separate downlink optical signals corresponding to at least one service type from the first mixed optical signal and transmit the downlink optical signals to the corresponding BOSA; and to combine the uplink optical signals transmitted by the BOSA into a third mixed optical signal.

[0051] When deploying the data transmission system of this application embodiment to specific application scenarios (such as large factories, single-user office buildings, etc.), the optical line terminal is set up in a dedicated equipment room or external equipment cabinet to achieve interconnection with the external public network. The ONU is set up in a location that enables data transmission after the user terminal connects. The first multiplexer / demultiplexer and ODN are installed and deployed in locations that can support the corresponding connection and signal transmission requirements of this application embodiment, depending on the specific application scenario. After deployment and connection are completed in the appropriate locations, the user terminal can achieve isolated data transmission of business data of different business types through the mutually isolated signal transmission links formed by the data transmission system of this application embodiment. Different business departments cannot arbitrarily view the data, eliminating the risk of business data leakage.

[0052] This invention also provides a data transmission method based on wavelength division multiplexing passive optical network. This data transmission method is applicable to the data transmission system based on wavelength division multiplexing passive optical network in any of the preceding embodiments, including but not limited to steps S110-S120.

[0053] Step S110: Each GPON OLT module of the optical line terminal sends a downlink optical signal corresponding to a service type to the demultiplexing interface of the first multiplexer / demultiplexer. The first multiplexer / demultiplexer combines multiple downlink optical signals into a first mixed optical signal and transmits the first mixed optical signal to the ODN. The ODN transmits the first mixed optical signal to multiple ONUs. The ONUs separate the downlink optical signal corresponding to at least one service type from the first mixed optical signal, convert the downlink optical signal into a first electrical signal, and transmit it to the corresponding user terminal.

[0054] Step S120: After the ONU converts the second electrical signal corresponding to at least one service type uploaded by the user terminal into an uplink optical signal, it combines the uplink optical signals into a third hybrid optical signal and transmits it to the ODN. The ODN combines each third hybrid optical signal into a second hybrid optical signal and transmits the second hybrid optical signal to the first multiplexer / demultiplexer. The first multiplexer / demultiplexer separates the second hybrid optical signal into uplink optical signals corresponding to each service type and transmits the uplink optical signals to the corresponding GPON OLT module. Each GPON OLT module receives the corresponding uplink optical signal.

[0055] Based on the wavelength division multiplexing-based data transmission system described above, after deploying the data transmission system to a specific application scenario, and connecting the user terminals configured by the business departments corresponding to each business type to the corresponding interfaces in the ONU, no other configuration is required. The data transmission system can then use the signal links formed by the connection method described above to achieve dedicated transmission of business data for different business types. Different business departments cannot arbitrarily view the data, thus eliminating the risk of business data leakage.

[0056] Note that the above are merely preferred embodiments and the technical principles applied in this invention. Those skilled in the art will understand that the embodiments of this invention are not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the protection scope of this invention. Therefore, although the embodiments of this invention have been described in detail above, the embodiments of this invention are not limited to the above embodiments. More other equivalent embodiments may be included without departing from the concept of the embodiments of this invention, and the scope of the embodiments of this invention is determined by the scope of the appended claims.

Claims

1. A data transmission system based on wavelength division multiplexing passive optical networks, characterized in that, include: The optical line terminal includes multiple GPON OLT modules. Each GPON OLT module is used to transmit downlink optical signals and receive uplink optical signals corresponding to a certain service type. The uplink and downlink optical signals of different service types each correspond to a unique wavelength. The first multiplexer includes multiple demultiplexing interfaces and one multiplexing interface. Each of the demultiplexing interfaces is connected to one of the GPON OLT modules, and the multiplexing interface is connected to a first interface of the ODN. The first multiplexer is used to combine multiple downlink optical signals into a first mixed optical signal and then transmit the first mixed optical signal to the ODN. And for separating the second hybrid optical signal into uplink optical signals corresponding to each of the service types, and then transmitting the uplink optical signals to the corresponding GPON OLT module; The ODN includes multiple second interfaces, each of which is connected to an ONU. The ODN is used to transmit the first mixed optical signal to each ONU, and to combine each third mixed optical signal into the second mixed optical signal, and then transmit the second mixed optical signal to the first multiplexer / demultiplexer. The ONU is used to separate downlink optical signals corresponding to at least one of the service types from the first mixed optical signals, convert the downlink optical signals into first electrical signals and transmit them to the corresponding user terminals. And for converting the second electrical signal uploaded by the user terminal, which corresponds to at least one of the service types, into an uplink optical signal, then combining the uplink optical signal into the third hybrid optical signal and transmitting it to the ODN; Each of the ONUs includes a first sub-network unit and a second sub-network unit; When the first sub-network unit is used for signal transmission, it separates downlink optical signals corresponding to at least one of the service types from the first mixed optical signal, converts the downlink optical signals into a first electrical signal and transmits it to the corresponding user terminal; and it is used to convert the second electrical signal corresponding to at least one of the service types uploaded by the user terminal into an uplink optical signal, and then synthesizes the uplink optical signals into the third mixed optical signal and transmits it to the ODN. When the second sub-network unit is used for signal transmission, it separates downlink optical signals corresponding to at least one of the service types from the first mixed optical signal, converts the downlink optical signals into first electrical signals and transmits them to the corresponding user terminal; and it is used to convert the second electrical signals corresponding to at least one of the service types uploaded by the user terminal into uplink optical signals, and then synthesizes the uplink optical signals into the third mixed optical signal and transmits them to the ODN. Only one of the first sub-network unit and the second sub-network unit can transmit signals at any given time.

2. The data transmission system based on wavelength division multiplexing passive optical network according to claim 1, characterized in that, The first sub-network unit includes multiple first BOSAs, and the second sub-network unit includes multiple second BOSAs. The multiple first BOSAs are used to transmit optical signals corresponding to different service types; the multiple second BOSAs are used to transmit optical signals corresponding to different service types.

3. The data transmission system based on wavelength division multiplexing passive optical network according to claim 2, characterized in that, The ONU includes an upper housing, a lower housing, and multiple circuit boards, which are disposed within the cavity formed by the upper and lower housings. Each circuit board is used to carry a first BOSA and a second BOSA corresponding to the same service type, and the service types corresponding to each circuit board are different.

4. The data transmission system based on wavelength division multiplexing passive optical network according to claim 3, characterized in that, The multiple circuit boards are stacked together.

5. The data transmission system based on wavelength division multiplexing passive optical network according to any one of claims 1-2, characterized in that, The ONU includes a main board and multiple slave boards. The main board includes multiple main interfaces, and each slave board includes a slave interface. Each slave board is used to carry BOSAs corresponding to different service types and is connected to the main board through the slave interface and the main interface.

6. The data transmission system based on wavelength division multiplexing passive optical network according to any one of claims 1-4, characterized in that, There are three types of services, and the wavelengths of the uplink optical signals corresponding to the three types of services are 1271nm, 1291nm and 1311nm, respectively, and the wavelengths of the downlink optical signals corresponding to the three types of services are 1331nm, 1351nm and 1371nm, respectively.

7. The data transmission system based on wavelength division multiplexing passive optical network according to any one of claims 2-4, characterized in that, The first multiplexer / demultiplexer includes three demultiplexing interfaces. The first multiplexer / demultiplexer is used to combine the downlink optical signals sent by the three GPON OLT modules into the first mixed optical signal, and to separate the second mixed optical signal into uplink optical signals corresponding to the three service types, and to transmit the three uplink optical signals to the receiving interfaces of the corresponding GPON OLTs respectively.

8. The data transmission system based on wavelength division multiplexing passive optical network according to any one of claims 2-4, characterized in that, Each ONU includes a second multiplexer / demultiplexer, which is used to separate a downlink optical signal corresponding to at least one of the service types from the first mixed optical signal and transmit the downlink optical signal to the corresponding BOSA. And for combining the uplink optical signal transmitted by BOSA into the third hybrid optical signal.

9. A data transmission method based on wavelength division multiplexing passive optical networks, characterized in that, The method is applicable to the data transmission system based on wavelength division multiplexing passive optical network as described in any one of claims 1 to 8, comprising: Each GPON OLT module of the optical line terminal sends a downlink optical signal corresponding to a service type to the demultiplexing interface of a first multiplexer / demultiplexer. The first multiplexer / demultiplexer combines multiple downlink optical signals into a first mixed optical signal and transmits the first mixed optical signal to the ODN. The ODN transmits the first mixed optical signal to multiple ONUs. The ONUs separate downlink optical signals corresponding to at least one service type from the first mixed optical signal, convert the downlink optical signals into a first electrical signal, and transmit it to the corresponding user terminal. The ONU converts the second electrical signal, which corresponds to at least one of the service types, uploaded by the user terminal into an uplink optical signal, then combines the uplink optical signal into the third hybrid optical signal and transmits it to the ODN. The ODN combines each of the third hybrid optical signals into the second hybrid optical signal and transmits the second hybrid optical signal to the first multiplexer / demultiplexer. The first multiplexer / demultiplexer separates the second hybrid optical signal into uplink optical signals corresponding to each of the service types and transmits the uplink optical signals to the corresponding GPON OLT modules. Each GPON OLT module receives the corresponding uplink optical signal.

Images