Space-based adaptive node terminal based on optical frequency comb and communication method

Abstract

The application provides a space-based adaptive node terminal based on an optical frequency comb and a communication method, and aims to solve the problem that different constellations are not matched in frequency, modulation format, transmission rate and coding mode in the prior art. The space-based adaptive node is used for adaptive switching between different systems, and interconnection and intercommunication between different constellation systems are realized. Thus, the whole space-based communication system can be efficiently and cooperatively operated under multiple constellation systems, an innovative solution is provided for a constellation network node interconnection and intercommunication architecture, and the application has a wide application prospect.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of space laser communication systems, in particular to a space-based adaptive node terminal based on an optical frequency comb and a communication method. BACKGROUND

[0002] Space laser communication has become a general means for constructing space satellite communication high-speed data transmission links due to its higher transmission rate, lower time delay and higher security. In the above various satellite constellation systems, the main indexes such as the center frequency, modulation format, working mode and coding mode adopted by the space laser communication link have no unified standard and cannot be interconnected. For example, the system of constellation 1 laser link adopts BPSK modulation mode, LDPC coding, and the communication rate is 2Gbps@1550nm, and the system of constellation 2 laser link adopts QPSK modulation mode, Polar coding, and the communication rate is 5Gbps@1530nm. Therefore, information can only be transmitted between the payload nodes of constellation 1 or constellation 2, and cross-constellation communication cannot be realized, resulting in an "information island". SUMMARY

[0003] The space-based adaptive node terminal is just to solve this problem. It is a reconfigurable space optical communication payload that can adapt to most optical inter-satellite link standards and can realize interconnection between different constellations and different systems within a constellation.

[0004] The optical frequency comb (OFC) naturally has the characteristics of multi-carrier comb teeth and large coverage bandwidth, which provides the condition for providing multiple different constellations through multiple comb teeth. In addition, the optical frequency comb has the characteristics of high frequency stability, strong spectral line phase coherence and integration, which makes it have the potential to be used as a key payload in a space laser communication system to realize data transmission between different constellations.

[0005] The present application proposes a space-based adaptive node terminal based on an optical frequency comb and a communication method. The characteristics of the multi-carrier comb teeth and the large coverage bandwidth of the optical frequency comb make different carrier wavelengths correspond to different constellations and communication systems, playing a "bridge" role. Specifically, each wavelength carrier signal generated by the optical frequency comb is connected to the nodes of different communication systems, thereby realizing the cooperative work between multiple constellations and multiple systems, and can adaptively switch various systems to complete the "bridge" function between different constellations and different system nodes in the same constellation.

[0006] In order to realize the above technical task, the present application adopts the following technical scheme to realize it:

[0007] A space-based adaptive node terminal based on an optical frequency comb, the adaptive node terminal comprising at least an optical head, a wide-spectrum optical amplifier, an optical frequency comb and an adaptive optical processor;

[0008] Wherein the optical head is used to realize adaptive node terminal transmission and receiving time-space optical information transmission; the wide-spectrum optical amplifier is used to complete power amplification and equalization of the optical frequency comb multi-carrier comb teeth, and ensure that the amplified comb teeth power meets the power requirements of optical signal receiving and transmitting; the optical frequency comb provides the carrier basis for interconnection and intercommunication between the adaptive node and multiple different constellations through its own multiple different wavelength carrier comb teeth; the adaptive optical processor is compatible with all target constellation communication systems, and completes modulation and demodulation, coding and decoding, and switching of multiple communication systems;

[0009] The adaptive node terminal utilizes each wavelength carrier signal generated by the optical frequency comb to realize adaptive switching, connection and intercommunication between multiple constellations and multiple systems.

[0010] In particular, the adaptive node terminal communication system includes communication wavelength, modulation mode, communication rate, coding mode, and link budget, and is respectively consistent with the communication system of each target connection constellation; the optical frequency comb is adjusted so that the wavelength of the comb teeth can cover the communication wavelength of all target connection constellations, and the comb teeth power is amplified by the wide-spectrum optical amplifier to meet the link budget required for communication with the constellation corresponding to the comb teeth; the adaptive optical processor is compatible with all target connection constellation systems that communicate with the node, and completes modulation, demodulation, coding and decoding of the corresponding communication system.

[0011] The application also provides a communication method using the space-based adaptive node terminal, and specifically includes the following steps:

[0012] Step S1: completing the design of the space-based adaptive node terminal based on the optical frequency comb;

[0013] Step S2: when any one of the Nth nodes of a target connection constellation M initiates a communication request, modulating and coding the information to be transmitted according to the wavelength, modulation format, transmission rate and coding mode of the laser communication system adopted by the target connection constellation M, and transmitting the information to the space-based adaptive node terminal based on the optical frequency comb;

[0014] Step S3: receiving the signal by the space-based adaptive node terminal, and selecting the carrier comb teeth in the optical frequency comb matched with the wavelength of the Nth node to receive the laser signal from the Nth node;

[0015] Step S4: completing the wavelength and communication system switching by the space-based adaptive node terminal; selecting the wavelength in the optical frequency comb matched with the target communication constellation P according to the communication demand of the target communication constellation P of the constellation M, completing the receiving of the signal of the Nth node of the constellation M by the space-based adaptive node terminal, and determining the modulation format, transmission rate and coding mode adopted by the constellation P;

[0016] Step S5: The space-based adaptive node terminal sends a signal; the space-based adaptive node terminal sends the signal to the Qth target node in the target communication constellation P after completing the conversion of the wavelength, modulation format, communication rate and coding mode matching the target communication constellation P by means of the optical frequency comb;

[0017] Step S6: The target node Q in the target communication constellation P receives the laser signal; the node Q receives the signal from the space-based adaptive node terminal and is ready for demodulation;

[0018] Step S7: The node Q in the target communication constellation P completes the reception and information extraction; the node Q performs reception and information extraction on the received signal, obtains all the information sent from the constellation M, and thus completes the information transmission and communication from the constellation M to the constellation P;

[0019] Step S8: Repeat steps S2-S7 until any two constellations in the space network realize information transmission and communication through the space-based adaptive node terminal.

[0020] Further, the step S1: completing the design and construction of the space-based adaptive node terminal based on the optical frequency comb, specifically includes the following steps:

[0021] Step S1-1: Clearly define the communication system adopted by each constellation in the space network that needs to be connected by the adaptive node terminal, including communication wavelength, modulation method, communication rate, coding method, and link budget;

[0022] Step S1-2: Adjust the optical frequency comb so that the wavelengths of the comb teeth cover the communication wavelengths of the target connection;

[0023] Step S1-3: Adjust the wide-spectrum optical amplifier so that it covers all the wavelengths of the optical frequency comb, and the amplified comb teeth power meets the link budget required for communication with the corresponding constellation;

[0024] Step S1-4: Configure the adaptive optical processor to be compatible with the system of the target connection constellation communicating with the space-based adaptive node terminal, and complete the modulation, demodulation, encoding and decoding of the corresponding communication system.

[0025] The space-based adaptive node terminal and communication method based on the optical frequency comb are aimed at solving the problem of mismatching of frequency, modulation format, transmission rate and coding mode between different constellations in the prior art, and realizing the interconnection and intercommunication between different constellation systems through adaptive switching of the space-based adaptive node terminal between different systems. Thus, the entire space-based communication system can efficiently and cooperatively operate under multiple constellation systems, providing an innovative solution for the constellation network node interconnection and intercommunication architecture, and having a wide application prospect. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 A schematic diagram of a space-based adaptive node terminal based on an optical frequency comb according to the present application;

[0027] Figure 2 A schematic diagram of the overall scheme principle according to the present application;

[0028] Figure 3 A flow chart of one embodiment of a method of the present application using a space-based adaptive node terminal based on an optical frequency comb. DETAILED DESCRIPTION

[0029] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The technical solutions in the embodiments of the present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0030] In order for those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should be within the scope of protection of the present application.

[0031] Referring to, Figure 1 A schematic diagram of the composition structure of a space-based adaptive node terminal based on an optical frequency comb according to the present application is given. The space-based adaptive node mainly includes four parts of an optical head, a wide-spectrum optical amplifier, an optical frequency comb and an adaptive optical processor. The main function of the optical head is to realize the transmission of spatial light information during the transmission and reception of the adaptive node terminal. The main function of the wide-spectrum optical amplifier is to complete the power amplification and equalization of the optical frequency comb teeth, to ensure that the power of the amplified teeth meets the power requirements of the optical signal reception and transmission. The optical frequency comb provides the carrier basis for the interconnection and intercommunication between the adaptive node and multiple different constellations through its own multiple carrier teeth of different wavelengths. The adaptive optical processor can be compatible with all target constellation communication systems, and can complete the functions of modulation and demodulation, coding and decoding, and switching of multiple communication systems.

[0032] The overall technical solution of the space-based adaptive node terminal based on an optical frequency comb according to the present application includes the following core parts:

[0033] 1. Design of a Space-Based Adaptive Node Terminal Based on an Optical Frequency Comb: The space-based adaptive node mainly consists of four parts: an optical head, a broadband optical amplifier, an optical frequency comb, and an adaptive optical processor. Specifically, it is necessary to define the communication system used by each constellation that the adaptive node needs to connect to, including communication wavelength, modulation method, communication rate, encoding method, and link budget. The optical frequency comb needs to be designed and adjusted so that the wavelength of its teeth can cover the communication wavelengths of all constellations. Then, a broadband optical amplifier needs to be designed to cover all wavelengths of the optical frequency comb, and the amplified power of the comb teeth must meet the link budget required for communication with the constellation corresponding to that comb tooth. The adaptive optical processor in the node needs to be compatible with the systems used by all constellations communicating with the node, and be able to perform modulation, demodulation, encoding, and decoding functions for the corresponding communication system.

[0034] 2. Adaptive Adjustment Function of Optical Frequency Comb: Utilizing the multi-wavelength characteristics of the optical frequency comb, adaptive switching can be performed according to the wavelength requirements of different constellations. Each constellation uses a different communication wavelength, and the optical frequency comb in the adaptive node payload can select a matching frequency for information transmission based on the communication needs between constellations.

[0035] 3. Frequency conversion and communication mode switching: During transmission, the optical frequency comb can convert the received signal in the optical frequency domain and simultaneously switch the communication mode to adapt to the communication standards of different constellations.

[0036] 4. Inter-constellation bridging function: When an initiating constellation needs to communicate with other target constellations, the adaptive node first receives the optical signal from the initiating constellation node and demodulates it using the corresponding wavelength via an optical frequency comb in the adaptive node. Then, the demodulated information is modulated and encoded in the adaptive optical processor according to the target constellation's communication system (including modulation method, communication rate, encoding method, etc.). Finally, the modulated and encoded signal is loaded onto the comb teeth of the optical frequency comb that match the wavelength of the target constellation and transmitted to the target constellation node, completing the information transmission from the initiating constellation to the target constellation. All of the above processes are completed in the space-based adaptive node terminal based on an optical frequency comb according to this invention.

[0037] See Figure 2 A schematic diagram of the overall scheme of the space-based adaptive node terminal and communication method based on optical frequency comb adopted in this invention is provided. Here, the adaptive node represents the adaptive node payload based on optical frequency comb, and nodes 1-N (the Nth node in constellation 1, and similar naming follows thereafter), 2-N, and 3-N represent constellation nodes under three different laser communication parameters.

[0038] like Figure 3 The following is an example of communication between initiating nodes 1-N in constellation 1 and target nodes 2-N in constellation 2: The specific steps include:

[0039] Step S1: Complete the design and construction of the space-based adaptive node terminal based on optical frequency comb. Determine the communication system adopted by each constellation connected by the adaptive node, including communication wavelength, modulation method, communication rate, encoding method, link budget, etc. Design the optical frequency comb to cover all the communication wavelengths of the constellation. Design a wide-spectrum optical amplifier that can cover all the wavelengths of the optical frequency comb and the amplified comb power can meet the link budget required for communication with the corresponding constellation. Design an adaptive optical processor that needs to be compatible with all the systems adopted by the constellation nodes communicating with the node, and can complete the modulation, demodulation, encoding and decoding functions of the corresponding communication system.

[0040] Step S2: Node 1-N in constellation 1 initiates a communication request. When node 1-N needs to transmit data to other constellation nodes, it first modulates and encodes the information to be transmitted according to the wavelength, modulation format, transmission rate and encoding method of the laser communication system adopted by constellation 1, and then transmits it to the space-based adaptive node terminal based on optical frequency comb.

[0041] Step S3: The space-based adaptive node terminal receives the signal. The space-based adaptive node terminal selects the carrier comb tooth in the optical frequency comb that matches the wavelength of node 1-N, receives the laser signal from node 1-N, and prepares for processing.

[0042] Step S4: The space-based adaptive node terminal completes the wavelength and communication system switching process. Since different constellation systems use different laser wavelengths and communication systems, wavelength and communication system switching is required. The space-based adaptive node terminal selects the wavelength in the optical frequency comb that matches the target communication constellation (e.g. constellation 2) according to the communication requirements of the target communication constellation. The adaptive node terminal receives the signal from node 1-N and determines the modulation format, transmission rate, encoding method, etc. used by constellation 2.

[0043] Step S5: The space-based adaptive node terminal sends the signal. The space-based adaptive node converts the wavelength, modulation format, communication rate and encoding method to match the target communication constellation 2, and then sends the signal to the target node 2-N in constellation 2.

[0044] Step S6: The target node 2-N in constellation 2 receives the laser signal. Node 2-N receives the signal from the space-based adaptive node and prepares for demodulation.

[0045] Step S7: Node 2-N in constellation 2 completes the reception and information extraction. Node 2-N receives the signal and extracts the information, obtaining all the information sent from constellation 1, thereby completing the information transmission and interworking between constellation 1 and constellation 2.

[0046] Step S8: Steps S2-S7, until any two constellations of the space network realize information transmission and connection through the space-based adaptive node terminal.

[0047] Through the technical solutions of the application, efficient and flexible laser communication between multiple constellations can be realized, the problem of non-compatibility of frequency, modulation format and coding mode in the prior art is solved, and the ability of interconnection and intercommunication between nodes of global space constellations is significantly improved.

Claims

1. A space-based adaptive node terminal based on an optical frequency comb, characterized in that: The adaptive node terminal includes at least an optical head, a broadband optical amplifier, an optical frequency comb, and an adaptive optical processor. The optical head is used to realize the transmission of spatial optical information in the transmission and reception of adaptive node terminals; the broadband optical amplifier is used to complete the power amplification and equalization of the multi-carrier comb teeth of the optical frequency comb, ensuring that the power of the amplified comb teeth meets the power requirements for optical signal reception and transmission; the optical frequency comb provides the carrier basis for interconnection between adaptive nodes and multiple different constellations through its own multiple carrier comb teeth of different wavelengths. The adaptive optical processor is compatible with the target constellation's communication system and performs modulation, demodulation, encoding, decoding, and switching of multiple communication systems. This adaptive node terminal utilizes the different communication systems corresponding to each wavelength carrier signal generated by the optical frequency comb to achieve adaptive switching and interconnection with multiple constellations and multiple systems.

2. The space-based adaptive node terminal based on optical frequency comb as described in claim 1, characterized in that: The adaptive node terminal communication system includes communication wavelength, modulation method, communication rate, encoding method, and link budget, which are consistent with the communication systems of each target connection constellation. By adjusting the optical frequency comb, the wavelength of its teeth can cover the communication wavelengths of all target connection constellations, and the power of the comb teeth is amplified by a broadband optical amplifier to meet the link budget required for communication with the constellation corresponding to that comb tooth. The adaptive optical processor is compatible with the systems of all target connection constellations communicating with the node, and completes the modulation, demodulation, encoding, and decoding of the corresponding communication system.

3. A communication method using a space-based adaptive node terminal based on an optical frequency comb as described in claim 1 or 2, characterized in that, Specifically, the steps include the following: Step S1: Complete the design of a space-based adaptive node terminal based on an optical frequency comb; Step S2: When any Nth node of a target connection constellation M initiates a communication request, the information to be transmitted is modulated and encoded according to the wavelength, modulation format, transmission rate and encoding method of the laser communication system adopted by the target connection constellation M and then transmitted to the space-based adaptive node terminal based on the optical frequency comb. Step S3: The space-based adaptive node terminal receives the signal. The space-based adaptive node terminal selects the carrier comb tooth in the optical frequency comb that matches the wavelength of the Nth node and receives the laser signal from the Nth node. Step S4: The space-based adaptive node terminal completes the wavelength and communication mode switching; according to the communication requirements of the target communication constellation P of constellation M, the space-based adaptive node terminal selects the wavelength in the optical frequency comb that matches the target communication constellation P, completes the reception of the signal of the Nth node of constellation M, and determines the modulation format, transmission rate and encoding method adopted by constellation P. Step S5: The space-based adaptive node terminal transmits a signal; after the space-based adaptive node terminal completes the conversion of wavelength, modulation format, communication rate and coding method to match the target communication constellation P with the help of an optical frequency comb, it transmits the signal to the Q target node in the target communication constellation P. Step S6: Target node Q in the target communication constellation P receives the laser signal; node Q receives the signal from the space-based adaptive node terminal and prepares to demodulate it; Step S7: Node Q in the target communication constellation P completes reception and information extraction; Node Q receives and extracts information from the received signal, obtains all the information sent from constellation M, and thus completes the information transmission and connection from constellation M to constellation P; Step S8: Repeat steps S2-S7 until any two constellations in the space network can achieve information transmission and connection through space-based adaptive node terminals.

4. The communication method for a space-based adaptive node terminal based on an optical frequency comb as described in claim 3, characterized in that, Step S1: Complete the design and construction of the space-based adaptive node terminal based on optical frequency comb, specifically including the following steps: Step S1-1: Determine the communication system used by each constellation that needs to be connected to the adaptive node terminal in the space network, including communication wavelength, modulation method, communication rate, coding method, and link budget; Step S1-2: Adjust the optical frequency comb so that the wavelength of its comb teeth covers the communication wavelength of the target connection; Step S1-3: Adjust the broadband optical amplifier to cover all wavelengths of the optical comb, and ensure that the power of the amplified comb teeth meets the link budget required for communication with the constellation corresponding to the comb teeth; Step S1-4: Configure the adaptive optical processor to be compatible with the target connection constellation for communication with the space-based adaptive node terminal, and complete the modulation, demodulation, encoding and decoding of the corresponding communication system.

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