CN114826407B

CN114826407B - Communication system, data transmission method and related equipment

Info

Publication number: CN114826407B
Application number: CN202110129206.4A
Authority: CN
Inventors: 兰鹏; 徐海东
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2021-01-29
Filing date: 2021-01-29
Publication date: 2024-06-25
Anticipated expiration: 2041-01-29
Also published as: CN114826407A; WO2022161156A1

Abstract

The embodiments of the present application disclose a communication system, a signal transmission method, and related equipment. The N communication units on the communication system are interconnected in a ring based on N pairs of optical cables, and optical signals of different wavelengths are transmitted on each optical cable at the same time, thereby realizing signal transmission between the N communication units, where N≥4 and N is an integer. There is a second communication unit among the N communication units, and the default wavelength information can be received through the communication interface. According to the default wavelength information, the optical signal from the first optical cable, whose target communication unit is not the second communication unit, is transmitted to the third communication unit. In the case where the communication unit of the communication system is greater than or equal to 4, the embodiments of the present application save the number of optical fibers and reduce costs.

Description

Communication system, data transmission method and related equipment

Technical Field

Embodiments of the present application relate to the field of communications, and in particular, to a communication system, a data transmission method, and related devices.

Background

The optical fiber communication has the advantages of large communication capacity, good confidentiality, long relay distance and the like, so that the optical fiber communication is widely applied. In practical applications, with the development of integration, how to reduce the number of optical cables in a communication system under the condition of ensuring communication is a problem to be solved.

In the existing communication system, any two communication units are connected through a plurality of pairs of optical cables, so that any two communication units can be directly connected through a pair of optical cables, and data transmission is performed by using the optical cables.

In such a communication system, since the optical cable for direct connection exists between any two communication units, the number of the optical cables is significantly increased with the increase of the number of the communication units, and the cost is increased.

Disclosure of Invention

The embodiment of the application provides a communication system, a data transmission method and related equipment, which are based on a ring topology mode, and each communication unit is connected by using an optical cable, so that the number of the optical cables is reduced, and the cost is saved.

A first aspect of an embodiment of the present application provides a communication system, including:

and N communication units which realize annular interconnection to the optical cables through N pairs of optical cables, wherein N is an integer greater than or equal to 4. Any one of the N communication units may perform data transmission with N-1 communication units other than itself through an optical cable, that is, each of the communication units may function as a transmitting end and a receiving end of data. In addition, each communication unit can also serve as a transfer station in the data transmission process to send the received signals to other communication units. For example, the first communication unit, the second communication unit, and the third communication unit are each included in the N communication units, the first communication unit and the second communication unit may be connected by a first optical cable, and the second communication unit and the third communication unit may be connected by a second optical cable. The second communication unit may receive, via the communication interface, default wavelength information before receiving the optical signal via the first optical cable, the default wavelength information including the first wavelength information, the target communication unit representing which wavelengths of the optical signal are the second communication unit. After the second communication unit receives the first optical signal through the first optical cable, it may determine, according to the default wavelength information, whether the target communication unit of the first optical signal is the second communication unit. If not, the second communication unit may transmit the first optical signal to the third communication unit via the second optical cable.

It should be noted that, in the process of using optical signals to perform data transmission between communication units, in order to ensure accuracy of data transmission, each optical signal has a corresponding start node and a corresponding end node, where the start node represents a start point of optical signal transmission in the communication unit, that is, a start communication unit in claims; the end node represents the end point of the transmission of the optical signal in the communication unit, i.e. the target communication unit in the claims.

In the embodiment of the application, based on a ring topology mode, N pairs of optical cables are used for connecting N communication units on the same communication system, and simultaneously, the optical signals with different wavelengths are transmitted on each optical cable to realize the signal transmission of the N communication units, so that compared with the prior art, N (N-1)/2 pairs of optical cables are used, the number of the optical cables is reduced and the cost is saved under the condition that the number of the communication units is greater than or equal to 4.

With reference to the first aspect, in a first implementation manner of the first aspect of the embodiment of the present application, the second communication unit may receive or send an optical signal with a specific wavelength in addition to being capable of transmitting the optical signal. The second communication unit may include a first filter, a first color light module, a second filter, and a second color light module. The first filter may determine, according to the default wavelength information, that the target communication unit is an optical signal of the second communication unit, and then the first color optical module may be capable of receiving the optical signals. The second color light module is used for sending a second light signal of which the initial communication unit is the second communication unit according to the default wavelength information, and then the second filter can remove interference in the second light signal and send the second light signal and the signal to be transmitted through to the third communication unit together.

In the embodiment of the application, the second communication unit can receive or transmit the optical signal with the specific wavelength besides the optical signal, so that the signal transmission among the communication units is realized, and the realizability of the technical scheme is improved.

The optical signals of a group of wavelengths, which may be one wavelength or a plurality of wavelengths, may be transmitted between any two communication units, which is not particularly limited herein, so long as each optical signal does not collide. The number of optical signals for data transmission between two different communication units may be the same, for example, data transmission may be performed between the first communication unit and the second communication unit by using 3 optical signals with different wavelengths, and data transmission may also be performed between the second communication unit and the third communication unit by using 3 optical signals with different wavelengths. In addition, the number of optical signals for data transmission between two different communication units may also be different, for example, data transmission may be performed between the first communication unit and the second communication unit by using 3 optical signals with different wavelengths, and data transmission may be performed between the second communication unit and the third communication unit by using 5 optical signals with different wavelengths. The kind of wavelength transmitted or received by the second communication unit is related to the number of communication units, and will be described below.

With reference to the first implementation manner of the first aspect, in a second implementation manner of the first aspect of the embodiment of the present application, if n=2n, the second communication unit needs to perform signal transmission with 2N-1 communication units. The second communication unit may include n×m first filters, n×m first color light modules, (n-1) ×m second filters, and (n-1) ×m second color light modules. m represents the number of identical wavelengths included in an optical signal of a set of wavelengths, m is greater than or equal to 1, and m is an integer. Each of the n×m first filters may filter out an optical signal of a different wavelength according to the default wavelength information, such that the n×m first filters filter out an optical signal of n×m different wavelengths in total. Each first color light module of the n×m first color light modules receives a light signal with a wavelength. In practical application, the frequency point of each first color light module needs to be consistent with the frequency point of each first filter, so that the accuracy of the second communication unit for receiving the light signals is ensured. Each of the (n-1) x m second color light modules may transmit a second light signal of which the initial communication unit is the second communication unit according to the default wavelength information, so that the (n-1) x m second color light modules transmit the second light signals of the (n-1) x m different wavelengths. Accordingly, each of the (n-1) x m second filters removes interference from the optical signal of one wavelength. In practical application, the frequency point of each second color light module needs to be consistent with the frequency point of each second filter, so that the accuracy of transmitting the optical signals by the second communication unit is ensured.

With reference to the first implementation manner of the first aspect, in a third implementation manner of the first aspect of the embodiment of the present application, when the number of communication units is 2n, the number of devices included in the second communication unit may be different from the second implementation manner of the first aspect. The second communication unit may include (n-1) x m first filters, (n-1) x m first color light modules, n x m second filters, and n x m second color light modules. m represents the number of identical wavelengths included in an optical signal of a set of wavelengths, m is greater than or equal to 1, and m is an integer. Each of the (n-1) x m first filters may filter out an optical signal of a different wavelength according to the default wavelength information such that the (n-1) x m first filters filter out an optical signal of a total of (n-1) x m different wavelengths. Each of the (n-1) x m first color light modules receives a light signal of a wavelength. In practical application, the frequency point of each first color light module needs to be consistent with the frequency point of each first filter, so that the accuracy of the second communication unit for receiving the light signals is ensured. Each of the n×m second color light modules may transmit a second light signal of which the initial communication unit is the second communication unit according to the default wavelength information, so that the n×m second color light modules transmit second light signals of n×m different wavelengths. Accordingly, each of the n×m second filters removes interference from the optical signal of one wavelength. In practical application, the frequency point of each second color light module needs to be consistent with the frequency point of each second filter, so that the accuracy of transmitting the optical signals by the second communication unit is ensured.

In the embodiment of the application, under the condition that the communication units in the communication system are even, the second communication unit has a plurality of wavelength allocation modes, and the second communication unit can be flexibly selected according to actual needs, thereby improving the flexibility of the technical scheme.

With reference to the first implementation manner of the first aspect, in a fourth implementation manner of the first aspect of the embodiment of the present application, when the number of communication units is 2n+1, the second communication unit may include n×m first filters, n×m first color light modules, n×m second filters, and n×m second color light modules. m represents the number of identical wavelengths included in an optical signal of a set of wavelengths, m is greater than or equal to 1, and m is an integer. Each of the n×m first filters may filter out an optical signal of a different wavelength according to the default wavelength information, such that the n×m first filters filter out an optical signal of n×m different wavelengths in total. Each first color light module of the n×m first color light modules receives a light signal with a wavelength. In practical application, the frequency point of each first color light module needs to be consistent with the frequency point of each first filter, so that the accuracy of the second communication unit for receiving the light signals is ensured. Each of the n×m second color light modules may transmit a second light signal of which the initial communication unit is the second communication unit according to the default wavelength information, so that the n×m second color light modules transmit second light signals of n different wavelengths. Accordingly, each of the n×m second filters removes interference from the optical signal of one wavelength. In practical application, the frequency point of each second color light module needs to be consistent with the frequency point of each second filter, so that the accuracy of transmitting the optical signals by the second communication unit is ensured.

In the embodiment of the application, different wavelength allocation schemes can be selected according to different numbers of the communication units, so that the number of the optical signals borne on each optical cable is uniform, the specification requirements on the communication units are consistent, and the cost is reduced.

With reference to the first aspect, or any one of the first to fourth implementation manners of the first aspect, in a fifth implementation manner of the first aspect of the embodiment of the present application, a transmission direction of the first optical signal may be a clockwise direction or a counterclockwise direction.

In the embodiment of the application, each communication unit can perform signal transmission in a clockwise direction or in a counterclockwise direction, a pair of optical fibers can realize communication in two directions, communication in one direction is failed (for example, a new communication unit is added), and full-ring single-side service maintenance can be realized, namely, data transmission is performed in the other direction. After the fault is solved, the service on the two sides of the whole ring can be restored, and the reliability of data transmission is improved.

In the process of using a pair of optical fibers for signal transmission by two communication units, each optical fiber in the pair of optical fibers may be used for transmitting an optical signal in one direction, and the wavelengths of the optical signals in two communication directions of the two communication units may be the same or different, which is not limited herein.

Alternatively, the two communication units may also implement signal transmission in two directions through one optical fiber. It should be noted that in the process of signal transmission by two communication units using one optical fiber, the wavelengths of the optical signals in the two directions are different in order to avoid contradiction between communications.

With reference to the first aspect, any one of the first to fifth implementation manners of the first aspect, in a sixth implementation manner of the first aspect of the embodiment of the present application, each of the N communication units may be a baseband unit (BBU). In some alternative embodiments, each communication unit in the communication system may be a Distributed Unit (DU).

With reference to the sixth implementation manner of the first aspect, in a seventh implementation manner of the first aspect of the embodiment of the present application, if the communication unit is a baseband unit, the communication system further includes a separate master control unit; if the communication unit is a distribution unit, any one of the N distribution units may be determined as a master unit. The main control unit can determine default wavelength information according to the number of the communication units and send the default wavelength information to the second communication unit through the communication interface.

In the embodiment of the application, different main control units can be determined according to different communication units, so that the flexibility of the technical scheme is improved.

A second aspect of an embodiment of the present application provides a signal transmission method, including:

The master control unit may determine the number of communication units in the communication system, and then determine default wavelength information for each communication unit according to the number of communication units. The default wavelength information includes an originating communication unit and a destination communication unit of the optical signal. And then, the main control unit can send default wavelength information to each communication unit through the communication interface of the communication unit, so that each communication unit carries out signal transmission according to the default wavelength information.

With reference to the second aspect, in a first implementation manner of the second aspect of the embodiment of the present application, if the number of communication units is 2n, the default wavelength information includes receiving n×m optical signals with different wavelengths, transmitting (n-1) ×m optical signals with different wavelengths, where n is greater than or equal to 2, n is an integer, m is greater than or equal to 1, and m is an integer.

With reference to the second aspect, in a second implementation manner of the second aspect of the embodiment of the present application, if the number of communication units is 2n, the default wavelength information includes receiving (n-1) ×m optical signals with different wavelengths, transmitting n×m optical signals with different wavelengths, where n is greater than or equal to 2, n is an integer, m is greater than or equal to 1, and m is an integer.

With reference to the second aspect, in a third implementation manner of the second aspect of the embodiment of the present application, if the number of communication units is 2n+1, the default wavelength information includes receiving n×m optical signals with different wavelengths, transmitting n×m optical signals with different wavelengths, where n is greater than or equal to 2, n is an integer, m is greater than or equal to 1, and m is an integer.

In the embodiment of the application, different wavelength allocation schemes can be selected according to different numbers of the communication units, so that the number of the optical signals borne on each optical cable is uniform, the specification requirements on the communication units are consistent, and the cost is reduced. Meanwhile, when the number of the communication units is even, different wavelength allocation schemes can be provided, so that the flexibility of the schemes is improved.

With reference to the second aspect or any one of the first to third implementation manners of the second aspect, in a fourth implementation manner of the second aspect of the embodiment of the present application, when a communication unit on the communication system is a baseband processor, the communication system further includes at least one master control unit, configured to calculate default wavelength information of each communication unit, and manage normal operation of the baseband processor. When the communication unit on the communication system is a distribution unit, the master control unit may be any one of the distribution units.

A third aspect of an embodiment of the present application provides a main control unit, including:

A processor, a memory, an input output device, and a bus. The processor, the memory and the input and output equipment are connected with the bus. The processor is configured to perform the steps of: the method comprises the steps of determining the number of communication units included in a communication system, and then determining wavelength default information of each communication unit according to the number of communication units, wherein the default wavelength information comprises an initial communication unit and a target communication unit of an optical signal. And finally, sending the wavelength default information to each communication unit through the communication interface of each communication unit so that each communication unit carries out signal transmission according to the default wavelength information.

The master control unit is configured to perform the method of the foregoing second aspect.

The advantages of the present invention are similar to those of the second aspect, and detailed description thereof will be omitted herein.

A fourth aspect of the embodiments of the present application provides a computer-readable storage medium having a program stored therein, which when executed by a computer, performs the method of the foregoing second aspect.

A fifth aspect of the embodiments of the present application provides a computer program product which, when executed on a computer, performs the method of the second aspect described above.

The advantages of the fourth and fifth aspects of the embodiments of the present application are similar to those of the second aspect, and detailed description thereof will be omitted herein.

Drawings

Fig. 1 is a schematic diagram of an application scenario of a communication system according to an embodiment of the present application;

fig. 2a is a schematic structural diagram of a communication system according to an embodiment of the present application;

fig. 2b is another schematic structural diagram of a communication system according to an embodiment of the present application;

fig. 2c is another schematic structural diagram of a communication system according to an embodiment of the present application;

fig. 3 is another schematic structural diagram of a communication system according to an embodiment of the present application;

Fig. 4 is a logic diagram of ring interconnection of communication units according to an embodiment of the present application;

fig. 5 is a schematic diagram of an application scenario of a baseband unit according to an embodiment of the present application;

fig. 6a is a schematic structural diagram of a communication unit according to an embodiment of the present application;

fig. 6b is another schematic structural diagram of a communication unit according to an embodiment of the present application;

fig. 7 is a schematic diagram of another application scenario of a baseband unit according to an embodiment of the present application;

fig. 8a is a schematic diagram of another application scenario of a baseband unit according to an embodiment of the present application;

fig. 8b is a schematic diagram of another application scenario of a baseband unit according to an embodiment of the present application;

Fig. 9 is a schematic flow chart of a signal transmission method according to an embodiment of the present application;

fig. 10 is a schematic structural diagram of a master control unit according to an embodiment of the present application.

Detailed Description

The embodiment of the application provides a communication system, a signal transmission method and related equipment, which are based on a ring topology, N pairs of optical cables are used for connecting N communication units on the same communication system, and simultaneously, the optical signals with different wavelengths are transmitted on each optical cable to realize the signal transmission of the N communication units, and compared with the prior art, the N (N-1)/2 pairs of optical cables are used, the number of the optical cables is reduced under the condition that the number of the communication units is more than or equal to 4, and the cost is saved.

First, an application scenario of the communication system provided by the embodiment of the present application is described. The communication system provided by the embodiment of the application can be applied to a wireless access network (radio access network, RAN) as frame or box type baseband processing equipment in a base station for signal transmission. In addition, the communication system may be used in other scenarios requiring large bandwidth and fiber optic communications, such as optical transmission networks or forward links, and is not limited in this regard. The embodiment of the application is described by taking the application of the communication system in the RAN as a frame type or box type baseband processing device as an example.

Referring to fig. 1, fig. 1 is a schematic diagram of an application scenario of a communication system according to an embodiment of the present application. As shown in fig. 1, the base station 110 includes an antenna 111, a remote radio unit 112 (remote radio unit, RRU), and a frame/cassette baseband processing device 113. The remote radio unit 112 may receive the signal sent by the antenna 111 and send the signal to the frame/cassette baseband processing device 113, where the frame/cassette baseband processing device 113 is capable of transmitting back (backhaul) the data carried by the signal to the core network.

The centralized radio access network (centralized radio access network, C-RAN) is a green radio access network architecture based on centralized processing, cooperative radio, real-time cloud computing. The C-RAN can reduce power consumption by reducing the number of base station rooms, and has advantages of low cost, high resource utilization rate, and the like, so that the C-RAN becomes a mainstream base station form. With the expansion of the architecture of centralized radio access networks (centralized radio access network, C-RAN), the demands on baseband interconnections are becoming more stringent and it is desirable that baseband interconnections be as cost effective as possible.

The embodiment of the application provides a communication system which can realize MESH interconnection among all communication units through optical signals with different wavelengths based on ring optical fiber topology. The different configurations of the communication system are described below. Fig. 2a to 2c are several examples of a frame type baseband processing apparatus, and fig. 3 is one example of a cassette type baseband processing apparatus. Referring to fig. 2a, fig. 2a is a schematic structural diagram of a communication system according to an embodiment of the application. As shown in fig. 2a, the frame baseband processing apparatus includes a fan, a baseband unit, a power supply, and a main control unit. The fan is used for cooling the baseband unit and plays a role in protection. The power supply is used for providing power support for normal operation of the baseband unit and the main control unit. The main control unit is used for determining default wavelength information, distributing optical signals with different wavelengths for the baseband unit, controlling the baseband unit to transmit signals, and transmitting signals from the remote radio unit received by the baseband unit to the core network through the communication interface. And the baseband units are mutually connected based on ring optical fiber topology, and each baseband unit is communicated with other baseband units through optical signals with different wavelengths. The default wavelength information may be calculated and determined by the main control unit according to the ring topology, or may be input manually in advance, or may be obtained by other modes, which is not limited herein.

It should be noted that fig. 2a is only a schematic structural diagram of a communication system in the embodiment of the present application, and in practical applications, the structure of the frame baseband processing device may also have other cases, please refer to fig. 2b and fig. 2c, and fig. 2b and fig. 2c are schematic structural diagrams of the communication system provided in the embodiment of the present application respectively. In fig. 2b and 2c, the constituent parts of the frame type baseband processing apparatus are the same as those of the frame type baseband processing apparatus shown in fig. 2a, except for the positions and the number of baseband units, and the positions and the number of main control units. The embodiment of the application provides that the communication system can realize the effect of saving the number of optical fibers based on the ring-shaped optical fiber topology when the number of the communication units is greater than or equal to 4, so in the embodiments shown in fig. 2b and fig. 2c, the number of the baseband units is greater than 4, and the positions of the baseband units can form a ring.

It should be noted that, in practical applications, the positions and numbers of baseband units, and the positions and numbers of master units may be selected according to the needs of the practical applications, so long as at least 4 baseband units and at least 1 master unit exist in the frame baseband processing device, and the positions of the baseband units are arranged to form a ring, which is not limited herein. Fig. 2a to 2c are only examples of the structure of the frame baseband processing apparatus according to the embodiment of the present application, and do not constitute a limitation of the frame baseband processing apparatus.

The baseband processing apparatus may be of a box-type structure in addition to the above-described structure. Referring to fig. 3, fig. 3 is a schematic structural diagram of a communication system according to an embodiment of the application. As shown in fig. 3, each baseband master-unit may be used as a box-type baseband processing device, that is, a distribution unit in the claims. The plurality of baseband master control integrated units can realize annular interconnection through a pair of annular optical fibers and transmit optical signals in two different directions. The baseband master control unit can realize the functions of the baseband units in the embodiments shown in fig. 2a to 2 c. Unlike the embodiment shown in fig. 2a to 2c, in the communication system shown in fig. 3, there may be no separate master unit, and any one of the unified units is controlled by the baseband, so that the master unit functions as in the embodiment shown in fig. 2a to 2 c.

Compared with the prior art that a switch is needed to be used for realizing interconnection of communication units, the embodiment of the application saves the space of a communication system and reduces the cost. And meanwhile, N or N pairs of optical fibers are used for realizing interconnection of N communication units, so that the number of the optical fibers is reduced, interfaces are simplified, and the probability of wiring errors is reduced.

In the optical fiber communication process, the communication system may use the baseband unit or the distribution unit to transmit signals, and in addition, may use other communication units to transmit signals, and select according to the needs of practical applications, which is not limited herein.

The embodiment of the present application will be described by taking a communication system using 6 communication units for transmitting optical signals as an example. Referring to fig. 4, fig. 4 is a logic diagram of ring interconnection of communication units according to an embodiment of the application. As shown in fig. 4, the 6 communication units are interconnected by 6 pairs of optical fibers based on a ring topology. The communication units perform data transmission through optical signals with different wavelengths, so that the communication between every two nodes is not interfered with each other. In the embodiment shown in fig. 4, the communication unit 1 and the communication unit 2 may use optical signals with a wavelength of λ1 for data transmission, the communication unit 1 and the communication unit 3 may use optical signals with a wavelength of λ2 for data transmission, and the communication unit 1 and the communication unit 4 may use optical signals with a wavelength of λ3 for data transmission. In the embodiment of the present application, the optical signals with the same wavelength may also be used in communications of different communication units, as shown in fig. 4, where the communication unit 3 and the communication unit 4 may also use the optical signal with the wavelength λ1 to perform data transmission, so that wavelength multiplexing between different communication units may be implemented, and frequency point resources may be saved.

In the embodiment shown in fig. 4, the communication unit 1 may transmit the optical signal with the wavelength λ1 to the communication unit 2 through the optical fiber 1, or may transmit the optical signal with the wavelength λ1 to the communication unit 2 through the optical fiber 2, and the selection is made according to the needs of the practical application, which is not limited herein. If the communication unit 1 transmits an optical signal with a wavelength of λ1 to the communication unit 2 through the optical fiber 1 and the wavelength of the optical signal transmitted by the communication unit 2 to the communication unit 1 is also λ1, the communication unit 2 should transmit the optical signal to the communication unit 1 using the optical fiber 2, thereby avoiding communication errors. The principle of signal transmission between any two other communication units is similar, and will not be described here again.

In practical applications, the optical signal transmitted between any two communication units may be a set of optical signals with a same wavelength, or may be optical signals with several different wavelengths, which is not limited herein. For example, in the clockwise direction, the communication unit 1 may transmit 2 optical signals of different wavelengths to the communication unit 2, and the communication unit 6 may also transmit 2 optical signals of different wavelengths to the communication unit 2, in which case, in order to avoid communication errors, the wavelengths of the optical signals transmitted by the communication unit 1 and the communication unit 6 should be different from each other: for example, the wavelengths of the optical signals transmitted by the communication unit 1 are λ1 and λ2, respectively, and the wavelengths of the optical signals transmitted by the unit 6 may be other wavelengths than λ1 and λ2. In addition to this, the communication unit 6 may also send more or less than 2 different wavelength optical signals to the communication unit 2, for example, the communication unit 6 may also send 4 different wavelength optical signals to the communication unit 2, which may be the wavelengths λ3, λ4, λ6 and λ8, respectively. The wavelength type and number of the optical signals between any two communication units are selected according to the needs of practical applications, and are not limited herein. For simplicity of explanation, the following embodiments will take an example of transmitting an optical signal with the same wavelength between any two communication units in one transmission direction.

In practical applications, the communication unit may be a baseband unit, or may be a distribution unit, or may be other communication units for optical fiber communication, which is not described herein. In the following embodiments, a communication unit is described as an example of a baseband unit.

For convenience of explanation, each baseband unit may be abstracted into a node, and a manner in which 6 baseband units communicate with each other based on a ring topology may be as shown in fig. 5. Referring to fig. 5, fig. 5 is a schematic diagram of an application scenario of a baseband unit in an embodiment of the present application.

As shown in fig. 5, the baseband units may perform signal transmission in a clockwise direction or may perform signal transmission in a counterclockwise direction, and the signal transmission may be selected according to the needs of practical applications, which is not limited herein. In the embodiment of the application, a pair of optical fibers can realize communication in two directions, communication in one direction fails (for example, a communication unit is newly added), and full-ring single-side service can be maintained, namely, data transmission is carried out in the other direction. After the fault is solved, the service on the two sides of the whole ring can be restored, and the reliability of data transmission is improved.

In this embodiment, a procedure in which node 1 communicates with other nodes will be described by taking clockwise communication as an example. In the clockwise direction, the node 1 can respectively send optical signals with wavelengths of λ1, λ2 and λ3 to the node 2, the node 3 and the node 4 to transmit data. The node 1 can also respectively receive optical signals with wavelengths of lambda 1 and lambda 2 sent by the node 5 and the node 6, so as to realize communication with the node 5 and the node 6.

In the process of the baseband units communicating with each other, one baseband unit may receive a plurality of optical signals, but there may be optical signals in the optical signals, which are not the own optical signals of the end node, so the baseband unit may determine the optical signals sent to the own optical signals from the optical signals of a plurality of wavelengths. The baseband unit can realize such functions, and the baseband unit provided by the embodiment of the application is described below with respect to the structure of the baseband unit itself. Referring to fig. 6a, fig. 6a is a schematic structural diagram of a communication unit according to an embodiment of the application.

As shown in fig. 6a, the baseband unit or the distribution unit may comprise a tunable filter and a color light module. The tunable filter may be a tunable micro-ring filter (TOADM) or a micro-ring filter (FLT MR), but may be other filters, provided that the wavelength of the optical signal filtered by the filter can be adjusted according to the actual application, and the disclosure is not limited thereto. It should be noted that in practical applications, the tunable filter 1 and the tunable filter 2 may be the same filter, so as to perform filtering of the optical signal in the clockwise and counterclockwise directions.

The baseband unit may further comprise a communication interface for receiving default wavelength information of itself, before signal transmission with other baseband units, the default wavelength information comprising wavelength information of an optical signal of which the originating communication unit is a self, and wavelength information of an optical signal of which the target communication unit is a self. In the process of using optical signals to carry out data transmission between communication units, in order to ensure the accuracy of data transmission, each optical signal has a corresponding initial node and a corresponding final node, and the initial node represents the starting point of the transmission of the optical signal in the communication unit, namely the initial communication unit in the claims; the end node represents the end point of the transmission of the optical signal in the communication unit, i.e. the target communication unit in the claims. The default wavelength information comprising the initial communication unit and the target communication unit is the basis that each baseband unit and other baseband units perform signal transmission and do not interfere with each other.

If the baseband unit shown in fig. 6a is the baseband unit No. 1, each of the tunable filters is used for filtering the optical signal of the destination communication unit or the baseband unit No. 1 of the initial communication unit, and the color optical module is used for receiving the optical signal of the baseband unit No. 1 of the destination communication unit or transmitting the optical signal of the baseband unit No. 1 of the initial communication unit.

Specifically, two optical fibers are provided between two communication units, for example, for the two communication units to communicate in the clockwise and counterclockwise directions, respectively. The baseband unit No. 1 can be regarded as the second communication unit in claims, and if the default wavelength information of the baseband unit No. 1 is an optical signal of reception wavelengths λ1, λ2 in the clockwise direction, an optical signal of transmission wavelengths λ1, λ2, and λ3. Then, as shown in fig. 6a, when the baseband unit No. 1 receives optical signals with wavelengths λ1, λ2, λ4 and λ5 from the first communication unit through the first optical cable, the micro-ring filter 1 and the micro-ring filter 2 correspond to the first filter in the claims, optical signals with wavelengths λ1 and λ2 can be filtered out, the color optical module 1 and the color optical module 2 correspond to the first color optical module in the claims, and optical signals with wavelengths λ1 and λ2 can be received, respectively, which process may be called "down wave". The optical signals with the wavelengths of λ4 and λ5 which are not filtered by the first filter are transmitted on the baseband unit No. 1, the color optical module 3, the color optical module 4 and the color optical module 5 correspond to the second color optical module in the claims, the optical signals with the wavelengths of λ1, λ2 and λ3 can be respectively emitted, the micro-ring filter 3, the micro-ring filter 4 and the micro-ring filter 5 correspond to the second filter in the claims, the interference in the optical signals emitted by the second color optical module can be respectively removed, so that the optical signals finally output by the baseband unit No. 1 are purer, and the process can be called as 'up wave'.

It should be noted that the frequency points of the optical signals processed by each micro-ring filter and each color optical module need to be kept consistent, which is beneficial to ensuring the accuracy and the rapidness of communication. For example, the micro-ring filter 1 is used for filtering out the optical signal with the wavelength λ1, and the color optical module 1 is used for absorbing the optical signal with the wavelength λ1. The function of the color light module 4 is to transmit an optical signal with a wavelength λ2, and the function of the micro-ring filter 4 is to remove interference factors in the optical signal with the wavelength λ2 transmitted by the color light module 4.

In practical applications, each color light module may have the capability of receiving and transmitting light signals. As shown in fig. 6a, in the counterclockwise direction, the color optical module 1 may send an optical signal with a certain wavelength to the micro-ring filter 1', and the color optical module 5 may receive the optical signal with a certain wavelength filtered by the micro-ring filter 5', so as to realize transmission of the optical signal in two directions. In this case, the wavelengths of the optical signals received or transmitted by the same color optical module may be the same, for example, the color optical module 1 may receive an optical signal having a wavelength λ1, and may also transmit an optical signal having a wavelength λ1 to the micro-ring filter 1'. It should be noted that the wavelengths of the optical signals received or transmitted by the same color optical module may also be different, and are selected according to the needs of practical applications, which is not limited herein.

It is noted that the number relationship between the color light module and the filter may be different from different perspectives. The number of first filters and first color light modules may be the same, and the number of second color light modules and second filters may be the same, in one transmission direction. If considering both clockwise and counterclockwise, one color light module may correspond to two filters, for example, color light module 1, corresponding to the first color light module in claim 1 in the clockwise direction, for receiving the light signal; in the counterclockwise direction, corresponds to the second color light module in the claims, for transmitting the light signal.

Alternatively, there may be a temporarily inactive micro-loop filter in the tunable filter, such as micro-loop filter 6 shown in fig. 6 a. Since default wavelength information between the communication units is adjustable in the embodiments of the present application, in some embodiments, baseband unit No. 1 may receive optical signals having wavelengths λ1, λ2, and λ4, in which case the micro-ring filter 6 may be used to filter optical signals having wavelengths λ4. In the embodiment of the application, the optical signals filtered by each filter can be adjusted according to different default wavelength information, so that the flexibility and the practicability of the technical scheme of the application are improved.

Optionally, the connection relationship between the tunable filter and the color light module and the communication unit may be pluggable or onboard, which is not limited herein. More commonly, when the communication unit is a baseband unit, the tunable filter and the color light module are generally pluggable to the baseband unit; when the communication unit is a distribution unit, the tunable filter and the color light module are typically integral with the distribution unit. The interconnection capability between the communication units can be realized through the adjustable filter and the color light module, the adjustable filter and the color light module can be isolated from the internal faults of the communication units, and the interconnection function of the ring topology can not be influenced as long as the communication system can supply power. Therefore, the failure can be localized inside the respective communication units without spreading. In addition, the adjustable filter and the color light module can be backed up according to channels or modules, and the fault of the single channel or the single module can not influence the intercommunication and interconnection process.

In practical applications, the number of the first filters, the first color optical modules, the second filters and the second color optical modules included in each baseband unit may be multiple, for example, in the case that the wavelength of the optical signal is single and the conversion frequency is slower, there may be only 1 first filter and 1 first color optical module, the wavelength of the optical signal filtered by the first filter is adjusted along with the wavelength of the optical signal received by the baseband unit, and the first color optical modules may also be synchronously adjusted, so as to implement time-sharing multiplexing of the first filters and the first color optical modules. The second filter and the second color light module may also be time-division multiplexed. The number of filters and color light modules is selected according to the needs of practical applications, and is not limited herein.

In some alternative embodiments, signal transmission in two directions between two communication units may also be achieved by one optical fiber. The following will briefly explain the case where signal transmission in two directions is achieved through one optical fiber between two communication units. Fig. 6b is a schematic structural diagram of a communication unit according to an embodiment of the present application.

For the color light module and the tunable filter, the color light module and the tunable filter cannot sense whether the two communication units perform signal transmission through a single optical fiber or a double optical fiber, and only perform optical signal receiving and transmitting according to default wavelength information. Thus, the processing pattern for the signals is similar to that in the embodiment shown in fig. 6 a. The difference is that the wavelengths of optical signals that the same two communication units communicate in different transmission directions are different in order to avoid contradiction of communication. For example, the color light module 1 may receive an optical signal having a wavelength λ1, in which case the wavelength of the optical signal transmitted by the color light module to the micro-ring filter 1' is not λ1.

In the case of realizing signal transmission in two directions between two communication units through one optical fiber, the communication system may further include a multiplexer/demultiplexer for multiplexing or demultiplexing the optical signal, so that signal transmission between the communication units is smoothly performed.

The communication system provided by the embodiment of the application can realize communication between any two communication units based on ring topology, and is related to wavelength allocation, namely, the process of determining default wavelength information. In practical applications, paths for transmitting and receiving signals between two nodes may be the same or different, and will be described below.

1. The transceiving paths are consistent.

In practical applications, the number of communication units may be determined according to the needs of practical applications, and the embodiment shown in fig. 7 is illustrated by taking 6 communication units as an example. In this embodiment, the communication unit is a baseband unit, refer to fig. 7, and fig. 7 is a schematic diagram of an application scenario of the baseband unit in the embodiment of the present application. For clarity and conciseness of illustration, fig. 7 shows only the wavelength allocation at nodes No. 1 and No. 2. The wavelength allocation logic at each node will be described below taking the example of transmitting signals in the clockwise direction and transmitting an optical signal of one wavelength between two communication units. The counter-clockwise direction may employ the same allocation logic as the clockwise direction and will not be described again here.

Before receiving the optical signal, the baseband unit may receive default wavelength information sent by the main control unit through the communication interface. The default wavelength information includes wavelength information of an optical signal using the baseband unit as a start communication unit and wavelength information of an optical signal using the baseband unit as a target communication unit. The default wavelength information is used for receiving and transmitting signals through the baseband unit. The communication interface may be a serial interface, a network interface, or other interface types, which is not limited herein. In addition, the communication unit may acquire default wavelength information based on a default listening channel.

Optionally, 3 wavelengths may be designated in the lower hand direction of the node No. 1, that is, 3 initial communication units are designated at the node No. 1 as optical signals with different wavelengths of the node No. 1, which are used for performing point-to-point communication with the node No. 1 and the nodes No. 2 to 4, respectively. And 2 wavelengths can be designated in the upper hand direction of the node 1, namely, the node 1 is provided with 2 target communication units which are optical signals with different wavelengths of the node 1 and are respectively used for point-to-point communication between the node 1 and the nodes 4 and 5. Based on the allocation mode, the wavelength allocation of the node 1 and other 5 nodes is realized. The wavelengths in the upper hand direction and the lower hand direction can be multiplexed, so that frequency point resources can be saved, and the cost is reduced.

Next, wavelength allocation is required for node No. 2. Because the wavelengths are already allocated between the node 1 and the node 2, only 4 wavelengths need to be allocated to the node 2. Two wavelengths may be allocated in each of the up-hand direction and the down-hand direction of node No. 2. When the wavelength of the lower hand direction is allocated, because λ2 and λ3 are already allocated to the communication of the node 1 and the nodes 3 and 4, λ1 and λ4 can be allocated to the lower hand direction of the node 2 under the condition that normal communication is not affected and frequency point resources are not increased as much as possible. Similarly, when the upper hand direction is allocated, because λ1, λ2 and λ3 have already been allocated to the communication between the node No. 1 and the node No. 2, no. 3 and No. 4, the upper hand direction of the node No. 2 can be allocated with λ4 and λ5 without affecting normal communication and without increasing frequency point resources as much as possible.

According to the above allocation logic, the allocation situation of each node can be as follows in table 1:

TABLE 1

Wavelength of

The end node 1

The end node 2

The end node 3

The end node 4

The end node 5

End node 6

Starting node 1

λ1

λ2

λ3

Originating node 2

λ1

λ4

Originating node 3

λ5

λ2

λ1

Originating node 4

λ5

λ3

Starting node 5

λ2

λ5

λ4

Starting node 6

λ1

λ4

As shown in table 1, since each node communicates with each other node, the sum of the wavelengths of a certain node as the initial node and the final node is the total node number minus 1. The starting node in table 1 corresponds to the starting communication unit in the claims and the ending node corresponds to the target communication unit in the claims.

Eventually, a wavelength topology of "Y over X Z under Z through" can be formed at each node. Wherein, the "X upper" means that there are X upper waves at the node, that is, there are X wavelengths with the node as the initial node; "under Y" means that there are Y downwaves at the node, i.e., there are Y wavelengths at the node as the end node; "Z-feedthrough" means that there are Z wavelengths transmitted at the node.

The upper and lower pass wavelength conditions of each node obtained according to the distribution method shown in table 1 are shown in table 2:

TABLE 2

	Upward wave	Down wave	Punch-through
				Node 1	λ1、λ2、λ3	λ1、λ2	λ4、λ5
Node 2	λ1、λ4	λ1、λ4、λ5	λ2、λ3
				Node 3	λ1、λ2、λ5	λ1、λ2	λ3、λ4
Node 4	λ3、λ5	λ3、λ4、λ5	λ1、λ2
				Node 5	λ2、λ4、λ5	λ2、λ5	λ1、λ3
Node 6	λ1、λ4	λ1、λ3、λ4	λ2、λ5

As shown in table 2, node No. 1 forms a "2-over-3-2-under-2-punch-through" topology. It should be noted that, table 1 and table 2 describe the wave flows from the connection and node points of view, and table 1 and table 2 only show an example of allocation, and other allocation manners without collision may be used in practical application, which is not described herein.

According to the distribution logic, the quantity of wavelengths distributed in the uplink direction and the downlink direction of each node is relatively close, so that the quantity of light waves borne on each optical cable is relatively uniform, the specification requirements on a baseband unit or a step-by-step unit are relatively consistent, and the cost is reduced. Meanwhile, each node communicates with other nodes through the upper hand direction or the lower hand direction, so that attenuation of optical signals caused by longer transmission paths can be reduced, and communication quality is improved.

In the embodiment of the application, the wavelengths can be allocated according to other allocation logics, so long as the communication between the nodes can be ensured not to interfere with each other, and the method is not limited in detail. For example, each node communicates with other nodes in a lower hand direction or an upper hand direction, and this allocation method can ensure communication of each node, but consumes more frequency resources than the allocation logic shown in table 1.

In the implementation of the application, the annular interconnection among the communication units is realized based on the annular optical fiber topology, the number of optical fibers used for interconnection is reduced, and the cost is reduced. Meanwhile, uplink waves or downlink waves of each communication unit can be flexibly allocated according to the requirements of practical application, dynamic or semi-static allocation of bandwidth is realized, and flexibility of a technical scheme is improved.

2. The transmission and reception paths are different.

The embodiment of the application takes 4 nodes as an example, and describes the case of different transceiving paths. In the clockwise direction, referring to fig. 8a, fig. 8a is a schematic diagram of an application scenario of a baseband unit in an embodiment of the present application. In the counterclockwise direction, please refer to fig. 8b, fig. 8b is a schematic diagram of an application scenario of a baseband unit in an embodiment of the present application.

The allocation logic of the embodiment shown in fig. 8a may be used to allocate wavelengths. After allocation, the allocation situation of each node in the clockwise direction can be as shown in table 3:

TABLE 3 Table 3

Wavelength of	The end node 1	The end node 2	The end node 3	The end node 4
					Starting node 1	λ1	λ2
Originating node 2			λ1	λ3
					Originating node 3			λ1
Originating node 4	λ1

As shown in table 3, since each node communicates with other points, the sum of the wavelengths of a certain node as the starting node and the end node is taken as the total node number minus 1. In the case of a communication system having 4 communication units, the sum of the wavelengths of the initial node and the final node is 3.

The upper and lower pass wavelength conditions of each node obtained according to the distribution method shown in table 3 are shown in table 4:

TABLE 4 Table 4

	Upward wave	Down wave	Punch-through
				Node 1	λ1、λ2	λ1
Node 2	λ1、λ3	λ1	λ2
				Node 3	λ1	λ1、λ2	λ3
Node 4	λ1	λ1、λ3

It should be noted that, table 3 and table 4 only show an example of allocation, and other allocation manners without collision may be used in practical application, which is not described herein.

The allocation of each node in the counterclockwise direction may be as shown in table 5:

TABLE 5

Wavelength of	The end node 4	The end node 3	The end node 2	The end node 1
					Originating node 4		λ2
Originating node 3			λ2	λ3
					Originating node 2	λ2		λ1
Starting node 1	λ3

The upper and lower pass wavelength conditions of each node obtained according to the distribution method shown in table 5 are shown in table 6:

TABLE 6

	Upward wave	Down wave	Punch-through
				Node 1	λ2	λ2、λ3
Node 2	λ2、λ3	λ2
				Node 3	λ1、λ2	λ2	λ3
Node 4	λ3	λ1、λ3	λ2

It should be noted that, table 5 and table 6 only show an example of allocation, and other allocation manners without collision may be used in practical application, which is not described herein.

In the embodiment of the present application, signal transmission may be performed between each communication unit according to a clockwise direction or a counterclockwise direction, and the signal transmission may be selected according to the needs of practical applications, which is not limited in particular herein. In the embodiment of the application, a pair of optical fibers can realize communication in two directions, communication in one direction fails (for example, a communication unit is newly added), and full-ring single-side service can be maintained, namely, data transmission is carried out in the other direction. After the fault is solved, the service on the two sides of the whole ring can be restored, and the reliability of data transmission is improved.

Referring to fig. 9, fig. 9 is a schematic flow chart of a signal transmission method according to an embodiment of the present application.

901. The master control unit determines the number N of communication units.

The communication units on the communication system may differ, as may the master control unit. If the communication unit on the communication system is a baseband unit, the communication system has a separate main control unit; if the communication unit on the communication system is a distribution unit, the master control unit may be any one of the distribution units. The main control unit can determine the number N of the communication units, and the number N is used as a basis for calculating default wavelength information. Wherein N is more than or equal to 4, and N is an integer.

902. The main control unit determines default wavelength information according to the number N of the communication units.

The master control unit may calculate default wavelength information after determining the number of communication units. Because the optical signals with a group of wavelengths can be transmitted between any two communication units, and the group of wavelengths can be optical signals with one wavelength or a plurality of wavelengths, the embodiment of the application uses m to represent the number of the same wavelengths included in the optical signals with the group of wavelengths, m is more than or equal to 1, and m is an integer.

In some alternative embodiments, if the number of communication units n=2n, the master control unit may determine that the default wavelength information includes receiving optical signals of n×m different wavelengths, and transmitting (N-1) ×m optical signals of different wavelengths.

In some alternative embodiments, if the number of communication units n=2n, the master control unit may also determine that the default wavelength information includes receiving (N-1) ×m different wavelength optical signals and transmitting n×m different wavelength optical signals.

In some alternative embodiments, if the number of communication units n=2n+1, the master control unit may determine that the default wavelength information includes receiving optical signals of n×m different wavelengths, and transmitting optical signals of n×m different wavelengths.

The specific content of the default wavelength information may be calculated according to the needs of practical applications, and the foregoing embodiments are not limited to the default wavelength information, and the type of the transmitted or received wavelength may be other, for example, when n=2n, the (N-2) x m optical signals are received, and the (n+1) x m optical signals are transmitted, which is not limited herein.

In some alternative embodiments, the default wavelength information may also be determined by manual pre-calculation and input into the master control unit. The main control unit obtains the default wavelength information in various ways, and the method is not limited herein.

903. The master control unit transmits respective default wavelength information to each communication unit.

After the main control unit acquires the default wavelength information, the main control unit can send the corresponding default wavelength information to each communication unit through the communication interface, so that each communication unit performs signal transmission according to the default wavelength information, and the signal transmission comprises at least one of signal receiving, signal sending and transparent transmission.

It should be noted that the default wavelength information in the embodiment of the present application is not a constant one, and can be flexibly adjusted according to the actual bandwidth requirement, and uplink waves or downlink waves with different frequencies can be allocated to each communication unit according to the requirement, so as to implement dynamic or semi-static bandwidth allocation.

Fig. 10 is a schematic structural diagram of a main control unit according to an embodiment of the present application, where the main control unit 1000 may include one or more central processing units (central processing units, CPU) 1001 and a memory 1005, and one or more application programs or data are stored in the memory 1005.

Wherein the memory 1005 may be volatile storage or persistent storage. The program stored in the memory 1005 may include one or more modules, each of which may be used to perform a series of operations performed by the main control unit. Still further, the central processor 1001 may be configured to communicate with the memory 1005, and execute a series of instruction operations in the memory 1005 on the main control unit 1000.

The master control unit 1000 may also include one or more power supplies 1002, one or more wired or wireless network interfaces 1003, one or more input/output interfaces 1004, and/or one or more operating systems, such as Windows ServerTM, mac OS XTM, unixTM, linuxTM, freeBSDTM, etc.

The cpu 1001 may perform the operations performed by the main control unit in the embodiment shown in fig. 9, which are not described herein.

It will be clear to those skilled in the art that, for convenience and brevity of description, specific working procedures of the above-described systems, apparatuses and units may refer to corresponding procedures in the foregoing method embodiments, which are not repeated herein.

In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices, and methods may be implemented in other manners. For example, the apparatus embodiments described above are merely illustrative, e.g., the division of the units is merely a logical function division, and there may be additional divisions when actually implemented, e.g., multiple units or components may be combined or integrated into another system, or some features may be omitted or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or units, which may be in electrical, mechanical or other form.

The units described as separate units may or may not be physically separate, and units shown as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional unit in the embodiments of the present application may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit. The integrated units may be implemented in hardware or in software functional units.

The integrated units, if implemented in the form of software functional units and sold or used as stand-alone products, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application may be embodied essentially or in part or all of the technical solution or in part in the form of a software product stored in a storage medium, including instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a read-only memory (ROM), a random access memory (random access memory, RAM), a magnetic disk, or an optical disk, or other various media capable of storing program codes.

Claims

1. A communication system, comprising:

the N communication units are in annular interconnection with each other through N pairs of optical fibers, wherein N is more than or equal to 4, and N is an integer;

The N communication units comprise a first communication unit, a second communication unit and a third communication unit, the first communication unit and the second communication unit are connected through a first optical cable, the second communication unit and the third communication unit are connected through a second optical cable, the second communication unit comprises a communication interface, and the second communication unit is any one of the N communication units;

the second communication unit is configured to:

receiving default wavelength information through the communication interface, wherein the default wavelength information comprises first wavelength information and second wavelength information, the first wavelength information represents that a target communication unit of an optical signal is the second communication unit, and the second wavelength information represents that a starting communication unit of the optical signal is the second communication unit;

If the target communication unit of the first optical signal from the first optical cable is not the second communication unit according to the default wavelength information, the first optical signal is transmitted to the third communication unit through the second optical cable;

If the target communication unit of the first optical signal from the first optical cable is the second communication unit according to the default wavelength information, receiving the first optical signal;

The second communication unit comprises a first filter, a first color light module, a second filter and a second color light module;

the first filter is configured to determine, according to the default wavelength information, that the target communication unit is an optical signal of the second communication unit;

The first color light module is used for receiving the light signal of the target communication unit which is the second communication unit;

The second color light module is used for sending a second light signal of which the initial communication unit is the second communication unit according to the default wavelength information;

the second filter is used for filtering interference signals in the second optical signal;

If n=2n, the number of the first filters in the second communication unit is n×m, the number of the first color light modules is n×m, the number of the second filters is (N-1) ×m, the number of the second color light modules is (N-1) ×m, m is greater than or equal to 1, and m is an integer;

Or the number of the first filters in the second communication unit is (n-1) multiplied by m, the number of the first color light modules is (n-1) multiplied by m, the number of the second filters is n multiplied by m, the number of the second color light modules is n multiplied by m, m is more than or equal to 1, and m is an integer;

if n=2n+1, the number of the first filters in the second communication unit is n×m, the number of the first color light modules is n×m, the number of the second filters is n×m, the number of the second color light modules is n×m, m is greater than or equal to 1, and m is an integer.

2. The communication system according to claim 1, wherein if n=2n, the number of the first filters in the second communication unit is n×m, the number of the first color light modules is n×m, the number of the second filters is (N-1) x m, the number of the second color light modules is (N-1) x m, m is equal to or greater than 1, and m is an integer;

each of the n×m first filters configured to determine an optical signal of the target communication unit as the second communication unit according to the default wavelength information, so that the n×m first filters determine optical signals of n×m different wavelengths;

Each first color light module of n×m first color light modules is configured to receive an optical signal of the second communication unit from the target communication unit, so that the n×m first color light modules receive the optical signals of n×m different wavelengths;

Each of (n-1) x m second color light modules for transmitting one of the second light signals according to the default wavelength information, so that the (n-1) x m second color light modules transmit the second light signals of (n-1) x m different wavelengths;

Each of (n-1) x m second filters for filtering an interference signal in one of the second optical signals, such that the (n-1) x m second filters filter the (n-1) x m second optical signals of different wavelengths.

3. The communication system according to claim 1, wherein if n=2n, the number of the first filters in the second communication unit is (N-1) x m, the number of the first color light modules is (N-1) x m, the number of the second filters is N x m, the number of the second color light modules is N x m, m is equal to or greater than 1, and m is an integer;

(n-1) x m first filters each for determining an optical signal of one of the target communication units as the second communication unit based on the default wavelength information, such that the (n-1) x m first filters determine (n-1) x m optical signals of different wavelengths;

Each of (n-1) x m first color light modules for receiving an optical signal of which one of the target communication units is the second communication unit, such that the (n-1) x m first color light modules receive the (n-1) x m optical signals of different wavelengths;

Each of the n×m second color light modules is configured to send one of the second optical signals according to the default wavelength information, so that the n×m second color light modules send the second optical signals with n×m different wavelengths;

each of the n×m second filters for filtering an interference signal in one of the second optical signals, such that the n×m second filters filter the n×m second optical signals of different wavelengths.

4. The communication system according to claim 1, wherein if n=2n+1, the number of the first filters in the second communication unit is n×m, the number of the first color light modules is n×m, the number of the second filters is n×m, the number of the second color light modules is n×m, m is equal to or greater than 1, and m is an integer;

each of the n×m second color light modules configured to transmit one of the second light signals such that the n×m second color light modules transmit n×m second light signals of different wavelengths;

Each of the n×m second filters is configured to filter an interference signal in one of the second optical signals, so that the n×m second filters filter interference signals in the second optical signals of the n×m different wavelengths.

5. The communication system according to any one of claims 1 to 4, wherein the transmission direction of the first optical signal is clockwise or counterclockwise.

6. The communication system according to any one of claims 1 to 4, wherein each of the N communication units is a baseband unit;

Or each of the N communication units is a distribution unit.

7. The communication system of claim 6, further comprising a master control unit if each of the communication units is the baseband unit;

If each communication unit is the distribution unit, determining any one of the N communication units as the main control unit;

the main control unit is used for:

determining the default wavelength information according to the number of the N communication units;

And sending the default wavelength information to the second communication unit through the communication interface.

8. A method of signal transmission applied to a communication system as claimed in any one of claims 1 to 7, comprising:

the method comprises the steps that a main control unit determines the number of communication units included in a communication system;

The main control unit determines wavelength default information of each communication unit according to the number of the communication units, wherein the default wavelength information comprises a starting communication unit and a target communication unit of an optical signal;

The main control unit sends the default wavelength information to each communication unit through the communication interface of each communication unit so that each communication unit carries out signal transmission according to the default wavelength information.

9. The method of claim 8, wherein determining wavelength default information for each communication unit based on the number of communication units comprises:

If the number of the communication units is 2n, determining the wavelength default information includes receiving n×m optical signals with different wavelengths, transmitting (n-1) ×m optical signals with different wavelengths, where n is greater than or equal to 2, n is an integer, m is greater than or equal to 1, and m is an integer.

10. The method of claim 8, wherein determining wavelength default information for each communication unit based on the number of communication units comprises:

if the number of the communication units is 2n, determining that the wavelength default information is to receive (n-1) multiplied by m optical signals with different wavelengths, and transmitting n multiplied by m optical signals with different wavelengths, wherein n is more than or equal to 2, n is an integer, m is more than or equal to 1, and m is an integer.

11. The method of claim 8, wherein determining wavelength default information for each communication unit based on the number of communication units comprises:

If the number of the communication units is 2n+1, determining that the wavelength default information is to receive optical signals of n multiplied by m different wavelengths, transmitting the optical signals of n multiplied by m different wavelengths, wherein n is more than or equal to 2, n is an integer, m is more than or equal to 1, and m is an integer.

12. A master control unit, comprising:

a processor, a memory, an input-output device, and a bus;

The processor, the memory and the input/output device are connected with the bus;

the processor is configured to perform the method of any one of claims 8 to 11.

13. A computer-readable storage medium, characterized in that the computer-readable storage medium stores a program which, when executed by the computer, performs the method of any one of claims 8 to 11.