A method and apparatus for coded cooperative transmission in a non-terrestrial network

Abstract

This invention discloses a coded cooperative transmission method and apparatus in a non-terrestrial network. The method transmits user-sent signals to cooperative nodes via an uplink channel; cooperative nodes receive the user-sent signals and obtain recovery information through extraction and recovery processing; cooperative nodes receive, process, and forward signals from each other via a cooperative interaction channel; and the cooperative nodes transmit the recovery information and the signals from the cooperating nodes to the ground destination receiver via a downlink channel. This invention utilizes the characteristics of polarization coding to establish a satellite node coded cooperative model in a non-terrestrial network, jointly optimizing key parameters such as coding rate and power allocation to improve the reliability and efficiency of information transmission in non-terrestrial networks.

Description

Technical Field

[0001] This invention relates to the field of wireless communication technology, and specifically to a coded cooperative transmission method and apparatus in a non-terrestrial network. Background Technology

[0002] Non-Terrestrial Network (NTN) is a network composed of satellite communication networks and high-altitude platform networks. It is an extension of terrestrial mobile communication systems into the sky. Based on new radio interface technologies, it forms a three-dimensional mobile broadband communication network, forming an integrated ubiquitous access and realizing voice and Internet services in all weather, all time, and all areas.

[0003] Currently, to meet the high reliability transmission quality requirements of NTN information, communication systems inevitably need to employ advanced error control technologies. Channel coding is one of the most critical technologies in the physical layer of wireless communication. The theoretical basis of polar codes is channel polarization. By recombining and splitting multiple independent physical channels with the same capacity, multiple virtual composite sub-channels with different capacities are generated. Based on this, during encoding, high-reliability composite sub-channels (called information bits) are used to transmit user information, while low-reliability composite sub-channels (called frozen bits) carry known fixed bits. The set of indices of the information bits is called the information bit sequence. Polar codes are a theoretically proven constructive coding scheme with achievable channel capacity, characterized by regular coding structure, low decoding complexity, and excellent error correction performance. Coding cooperation is a key technology in wireless cooperative communication. It combines cooperative diversity and channel coding to simultaneously obtain diversity gain and coding gain, effectively combating channel fading. For scenarios where wireless terminal devices cannot directly use MIMO (multiple-input multiple-output) technology due to limitations such as size and hardware computing power, single-antenna users can achieve diversity transmission of codewords by sharing antennas with each other, thus achieving a virtual MIMO effect.

[0004] Therefore, how to invent a coding cooperative transmission method in non-terrestrial networks to improve the reliability and efficiency of information transmission in non-terrestrial networks has become an urgent problem to be solved. Summary of the Invention

[0005] To this end, the present invention provides a coding cooperative transmission method and apparatus in non-terrestrial networks. By utilizing the characteristics of polar coding construction, a coding cooperative model of satellite nodes in non-terrestrial networks is established, and key parameters such as coding rate and power allocation are jointly optimized to improve the reliability and efficiency of information transmission in non-terrestrial networks.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a method for coded cooperative transmission in a non-terrestrial network, comprising:

[0007] The user sends a signal to the collaborating node via the uplink channel; the collaborating node receives the user's signal and obtains recovery information through extraction and recovery processing.

[0008] Collaborating nodes receive, process, and forward signals from each other through a collaborative interaction channel.

[0009] The cooperating node transmits the recovery information and the signals of the cooperating nodes to the ground destination receiver via the downlink channel.

[0010] As a preferred scheme for coded cooperative transmission in non-terrestrial networks, cooperative nodes include high, medium, and low orbit satellites in NTN, as well as airships, balloons, and UAV aerial platforms.

[0011] As a preferred scheme for coded cooperative transmission in non-terrestrial networks, the cooperative interaction channel between cooperative nodes is encoded using polar codes; the encoded codeword expression is:

[0012]

[0013] In the formula, x N The encoded codeword; Both 'v' and 'v' are short codewords; symbols The symbol "|" represents the XOR operation; it represents two short codewords. B is concatenated with v to form a long codeword of length N; N Let be an N×N row permutation matrix.

[0014] As a preferred embodiment of a coded cooperative transmission method in a non-terrestrial network, cooperative nodes transmit information through a coded cooperative approach; the steps for transmitting information through this coded cooperative approach are as follows:

[0015] Collaborating nodes S1 and S2 generate submatrix G1 and information bit sequence based on the generated matrix. Each K1 information bits are encoded into a subframe.

[0016] In the first time slot, cooperating node S1 communicates via the downlink. Transmit subframes at power P1 To ground receiver D; cooperative node S2 via downlink Transmit subframes at power P2 The information is transmitted to the ground receiver D; the cooperating node S1 obtains the estimation information of the cooperating node S2 through the cooperative interaction channel; the cooperating node S2 obtains the estimation information of the cooperating node S1 through the cooperative interaction channel.

[0017] In the second time slot, cooperating nodes S1 and S2 generate the submatrix G2 of the matrix and the information bit sequence. Encode each of the K2 information bits into a subcode.

[0018] Collaborating node S1 re-encodes the estimated information from collaborating node S2 into Will AND subcode Subframes are obtained through XOR operations. Collaborating node S2 re-encodes the estimated information from collaborating node S1 into Will AND subcode Subframes are obtained through XOR operations.

[0019] Collaborating node S1 via downlink Transmit subframes at power P2 To ground receiver D; cooperative node S2 via downlink Transmit subframes at power P1 To ground receiving end D;

[0020] Ground receiver D transmits subframes sent by cooperating node S1 Subframes sent by cooperating node S2 The data is spliced ​​together to obtain the spliced ​​signal from cooperating node S1; the ground receiver D transmits the subframes sent by cooperating node S2. Subframes sent by cooperating node S1 Perform splicing to obtain the splicing signal of the cooperating node S2;

[0021] The ground receiver D decodes the spliced ​​signals of cooperating node S1 and cooperating node S2 respectively to obtain the transmission information of cooperating node S1 and cooperating node S2.

[0022] As a preferred scheme for coded cooperative transmission in non-terrestrial networks, a global performance joint optimization strategy for the NTN polar coding cooperative system is designed based on reinforcement learning algorithm; the optimal cooperative coding rate and optimal power allocation parameters are determined through the global performance joint optimization strategy of the NTN polar coding cooperative system.

[0023] The problem that the global performance joint optimization strategy of the NTN polar coding cooperative system needs to solve is expressed as:

[0024]

[0025] In the formula, f i and F o These represent the objective functions for individual performance metrics and the overall performance metrics of the collaborating nodes, respectively. These are the code rates of cooperating nodes S1 and S2, respectively; P1 and P2 are the subframe signal transmission powers of the two transmission slots, respectively. These are the downlink channel signal-to-noise ratios of the two cooperating nodes S1 and S2, respectively. η represents the frame error rates of the two cooperating nodes S1 and S2, respectively. o The throughput efficiency of the NTN coding cooperative system.

[0026] The present invention also provides a coding cooperative transmission apparatus in a non-terrestrial network, based on the above-mentioned coding cooperative transmission method in a non-terrestrial network, comprising:

[0027] The collaborative node receives and processes signals, which is used to transmit user-sent signals to the collaborative node through the uplink channel; the collaborative node receives the user-sent signals and obtains recovery information through extraction and recovery processing.

[0028] The signal transmission module between cooperative nodes is used to receive, process, and forward signals from each other through a cooperative interaction channel.

[0029] The signal transmission module from the cooperating node to the ground receiver is used by the cooperating node to transmit the recovery information and the signals of the cooperating nodes to the ground destination receiver through the downlink channel.

[0030] As a preferred embodiment of a coded cooperative transmission device in a non-terrestrial network, the cooperative node receiving and processing signal module includes high-, medium-, and low-orbit satellites in the NTN, as well as airships, balloons, and UAV aerial platforms.

[0031] As a preferred embodiment of a coded cooperative transmission device in a non-terrestrial network, the cooperative interaction channel between cooperative nodes in the signal transmission module is encoded using polar codes; the encoded codeword expression is:

[0032]

[0033] In the formula, x N The encoded codeword; Both 'v' and 'v' are short codewords; symbols The symbol "|" represents the XOR operation; it represents two short codewords. B is concatenated with v to form a long codeword of length N; N Let be an N×N row permutation matrix.

[0034] As a preferred embodiment of a coded cooperative transmission device in a non-terrestrial network, the sub-module for transmitting information via coded cooperation in the signal transmission module from the cooperative node to the ground receiver includes:

[0035] The self-frame generation submodule is used by cooperating nodes S1 and S2 to generate submatrix G1 and information bit subsequence. Each K1 information bits are encoded into a subframe.

[0036] The self-subframe transmission submodule is used in the first time slot, where the cooperating node S1 transmits data via the downlink. Transmit subframes at power P1 To ground receiver D; cooperative node S2 via downlink Transmit subframes at power P2 The information is transmitted to the ground receiver D; the cooperating node S1 obtains the estimation information of the cooperating node S2 through the cooperative interaction channel; the cooperating node S2 obtains the estimation information of the cooperating node S1 through the cooperative interaction channel.

[0037] The sub-code generation submodule is used in the second time slot by cooperating nodes S1 and S2 to generate sub-matrix G2 and information bit sub-sequences based on the generation matrix. Encode each of the K2 information bits into a subcode.

[0038] The composite subframe generation submodule is used by cooperative node S1 to re-encode the estimated information of cooperative node S2 into... Will AND subcode Subframes are obtained through XOR operations. Collaborating node S2 re-encodes the estimated information from collaborating node S1 into Will AND subcode Subframes are obtained through XOR operations.

[0039] Composite subframe transmission submodule, used by cooperating node S1 to transmit data via downlink. Transmit subframes at power P2 To ground receiver D; cooperative node S2 via downlink Transmit subframes at power P1 To ground receiving end D;

[0040] The subframe splicing submodule is used by the ground receiver D to transmit subframes sent by the cooperating node S1. Subframes sent by cooperating node S2 The data is spliced ​​together to obtain the spliced ​​signal from cooperating node S1; the ground receiver D transmits the subframes sent by cooperating node S2. Subframes sent by cooperating node S1 Perform splicing to obtain the splicing signal of the cooperating node S2;

[0041] The splicing signal decoding submodule is used by the ground receiver D to decode the splicing signals of cooperating node S1 and cooperating node S2 respectively, so as to obtain the transmission information of cooperating node S1 and cooperating node S2.

[0042] As a preferred embodiment of a coding cooperative transmission device in a non-terrestrial network, in the signal transmission module from the cooperative node to the ground receiver, a global performance joint optimization strategy for the NTN polar coding cooperative system is designed based on a reinforcement learning algorithm; through the global performance joint optimization strategy for the NTN polar coding cooperative system, the optimal cooperative coding rate and the optimal power allocation parameters are determined;

[0043] The problem that the global performance joint optimization strategy of the NTN polar coding cooperative system needs to solve is expressed as:

[0044]

[0045] In the formula, f i and F o These represent the objective functions for individual performance metrics and the overall performance metrics of the collaborating nodes, respectively. These are the code rates of cooperating nodes S1 and S2, respectively; P1 and P2 are the subframe signal transmission powers of the two transmission slots, respectively. These are the downlink channel signal-to-noise ratios of the two cooperating nodes S1 and S2, respectively. η represents the frame error rates of the two cooperating nodes S1 and S2, respectively. o The throughput efficiency of the NTN coding cooperative system.

[0046] This invention has the following advantages: It transmits user-sent signals to cooperating nodes via an uplink channel; the cooperating nodes receive the user-sent signals and obtain recovery information through extraction and recovery processing; the cooperating nodes receive, process, and forward signals from each other via a cooperative interaction channel; and the cooperating nodes transmit the recovery information and the signals from the cooperating nodes to the ground destination receiver via a downlink channel. This invention leverages the inherent coding characteristics of polar codes to achieve cooperative communication between space-based and air-based processing and forwarding nodes in an NTN, simultaneously acquiring coding gain and diversity gain, and employing reinforcement learning methods to jointly optimize the key parameters of code rate and power for cooperating nodes. In this invention, the information bit error rate at the NTN ground receiver is significantly reduced compared to the non-cooperative case. After optimizing the code rate and power parameters under different downlink conditions, the overall performance of the system, including bit error rate and throughput efficiency, is significantly improved. Attached Figure Description

[0047] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0048] The structures, proportions, sizes, etc. illustrated in this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed herein, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0049] Figure 1 This is a schematic diagram of a coding cooperative transmission method in a non-terrestrial network provided in Embodiment 1 of the present invention;

[0050] Figure 2 This is a schematic diagram illustrating the specific implementation process of a coding cooperative transmission method in a non-terrestrial network provided in Embodiment 1 of the present invention;

[0051] Figure 3 This is a schematic diagram of the encoding process of polarization coding cooperation between NTN satellite nodes in a coding cooperation transmission method in a non-terrestrial network provided in Embodiment 1 of the present invention;

[0052] Figure 4 This is a schematic diagram of an architecture for a coding cooperative transmission device in a non-terrestrial network, as provided in Embodiment 2 of the present invention. Detailed Implementation

[0053] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0054] Example 1

[0055] See Figure 1 and Figure 2 Embodiment 1 of the present invention provides a method for coded cooperative transmission in a non-terrestrial network, comprising the following steps:

[0056] S1. The user-sent signal is transmitted to the collaborating node via the uplink channel; the collaborating node receives the user-sent signal and obtains recovery information through extraction and recovery processing.

[0057] S2. Cooperative nodes receive, process, and forward signals from each other through a cooperative interaction channel.

[0058] S3. The cooperating node transmits the recovery information and the signals of the cooperating nodes to the ground destination receiver through the downlink channel.

[0059] In this embodiment, the cooperating nodes include high-, medium-, and low-Earth orbit satellites in the NTN, as well as aerial platforms such as airships, balloons, and drones. This embodiment uses satellites as an example.

[0060] In this embodiment, in step S1, the signal sent by the user is transmitted to the cooperating node through the uplink channel; the cooperating node receives the signal sent by the user and obtains recovery information through extraction and recovery processing;

[0061] Specifically, such as Figure 2 As shown, ground user 1 and user 2 communicate via the uplink channel. Signals are sent to their respective satellite nodes S1 and S2, and the satellite nodes receive the signals and extract the recovery information.

[0062] In this embodiment, the signal transmission channels of different users and different satellite nodes satisfy orthogonality so that the receiver can distinguish the signals sent by different senders. This embodiment takes time division multiple access as an example, but frequency division multiple access, code division multiple access and other channel multiplexing methods can also be used.

[0063] In this embodiment, in step S2, the cooperating nodes receive, process and forward signals from each other through a cooperative interaction channel.

[0064] Specifically, each satellite node can communicate with each other via the inter-satellite communication channel C. in It receives, processes, and forwards signals from satellite nodes that it collaborates with.

[0065] In this embodiment, the cooperating satellite nodes use polar codes as the channel coding scheme to transmit information through a coding cooperation method.

[0066] Let N be the length of the encoded codeword. and These represent the sets of indices for the information bits to be encoded and the frozen bits, respectively. The number of elements in the set is K0. The set of bits to be encoded is u. N =(u1,u2,...,u N The encoded codeword x N It can be represented as:

[0067]

[0068] In the formula, G N B is the polar code generator matrix; N Represent an N×N row permutation matrix; and The row number belongs to and G N Submatrices; symbols This indicates the XOR operation.

[0069] make If the frozen bits are set to all zero bits, then we can obtain:

[0070]

[0071] In the formula, and These respectively indicate that according to the row number, they belong to and Selected G N The submatrix.

[0072] It can be further rewritten as:

[0073]

[0074] In the formula, G1 and G2 represent the row index sequence numbers corresponding to... Hezhong The elements and column index numbers of G that belong to {i|1≤i≤N / 2} N The submatrix.

[0075] Let the codewords v and w be respectively:

[0076]

[0077] The generated codeword can then be represented as:

[0078]

[0079] In the formula, the symbol “|” represents two short codewords. Connect v to form a long codeword with a code length of N.

[0080] In this embodiment, in step S3, the cooperating node transmits the recovery information and the signals of the cooperating nodes to the ground destination receiver through the downlink channel.

[0081] Specifically, each satellite node reprocesses the recovered data and forwards it via the downlink channel. Transmitted to the ground destination receiver D; wherein, the downlink channel type is a fading channel.

[0082] In this embodiment, the coding cooperation scheme between satellite nodes S1 and S2 is as follows: Figure 3 As shown, the specific steps are as follows:

[0083] S31, Collaborating nodes S1 and S2 generate submatrix G1 and information position subsequence based on the generated matrix submatrix G1. Each K1 information bits are encoded into a subframe.

[0084] S32. In the first time slot, cooperating node S1 communicates via the downlink. Transmit subframes at power P1 To ground receiver D; cooperative node S2 via downlink Transmit subframes at power P2 The information is transmitted to the ground receiver D; the cooperating node S1 obtains the estimation information of the cooperating node S2 through the cooperative interaction channel; the cooperating node S2 obtains the estimation information of the cooperating node S1 through the cooperative interaction channel.

[0085] S33. In the second time slot, cooperating nodes S1 and S2 generate submatrix G2 and information position subsequence based on the generated matrix submatrix G2. Encode each of the K2 information bits into a subcode.

[0086] S34, Collaborating node S1 re-encodes the estimated information of collaborating node S2 into... Will AND subcode Subframes are obtained through XOR operations. Collaborating node S2 re-encodes the estimated information from collaborating node S1 into Will AND subcode Subframes are obtained through XOR operations.

[0087] S35 and cooperating node S1 communicate via downlink Transmit subframes at power P2 To ground receiver D; cooperative node S2 via downlink Transmit subframes at power P1 To ground receiving end D;

[0088] S36, Ground receiver D transmits the subframe sent by cooperating node S1 Subframes sent by cooperating node S2 The data is spliced ​​together to obtain the spliced ​​signal from cooperating node S1; the ground receiver D transmits the subframes sent by cooperating node S2. Subframes sent by cooperating node S1 Perform splicing to obtain the splicing signal of the cooperating node S2;

[0089] S37 and the ground receiving end D decode the spliced ​​signals of cooperating node S1 and cooperating node S2 respectively to obtain the transmission information of cooperating node S1 and cooperating node S2.

[0090] Specifically, the ground receiver decodes the spliced ​​signals separately, for example, by using a fast, continuous elimination decoding algorithm with low complexity and low latency to obtain the transmission information of each satellite node.

[0091] In this embodiment, for each cooperating satellite node, the signal transmission power in the two time slots is assumed to satisfy:

[0092] P1 + P2 = 2P T

[0093] In the formula, P T The preset power value;

[0094] The number of information bits satisfies:

[0095] K1+K2=K0

[0096] In the formula, K0 is the preset number of information bits;

[0097] Then the global coding code rate for each satellite node is R0 = K0 / N.

[0098] Assuming the downlink is a Rayleigh slow fading channel, the channel fading factor h is [value missing] within two subframe transmission slots for each satellite node. i,j Keep it fixed. Assume the inter-satellite link between the two cooperating satellite nodes is an ideal channel, meaning each satellite node can successfully obtain transmitted information from the subframe signals sent by its cooperating satellite nodes.

[0099] To improve the global performance of the NTN polar coding cooperative system in terms of bit error probability and throughput efficiency, a reinforcement learning algorithm is used to design a joint optimization method for the global performance of the NTN polar coding cooperative system, and to determine the optimal cooperative coding code rate, power allocation and other key system parameters.

[0100] Specifically, building a learning environment State s represents a conditional configuration sequence. This displays the code rates of two satellite nodes S1 and S2 in the NTN coding cooperative system. The subframe signal transmit power P1, P2 of the two transmission slots, and the downlink channel signal-to-noise ratio of the two satellite nodes S1, S2.

[0101] Actions are represented as 2D sets And it satisfies P2 = 2P T -P1, Alternate bitrate set, 0 <P1<2P T Different action options are available by selecting different R0 or P1.

[0102] The reward set r includes the frame error rate of each cooperating satellite node. and the throughput efficiency η of the NTN coding cooperative system o Overall return value r o This represents the combined performance result of two satellite nodes in the NTN coding collaboration system during the learning process.

[0103] Based on the Markov Decision Process (MDP) mapping relationship of reinforcement learning, the state transition process is executed sequentially. Given... Then the next state s′ can be determined. In the multi-objective reinforcement learning process, the agent and the MDP learning environment interact with each other in various discrete stages. In stage k, the agent observes the state s. k According to the strategy Select the corresponding action At the same time, obtain corresponding rewards from the environment. k , The goal of an agent is to optimize its strategy to maximize overall returns.

[0104] The optimization strategy needs to address the following issues:

[0105]

[0106] In the formula, f i and F o These represent the objective functions for individual performance indicators and the comprehensive performance indicator of a satellite node, respectively.

[0107] In this embodiment, the classic Q-learning algorithm is used, but other effective reinforcement learning algorithms can also be employed. Through interaction with the environment, the agent synchronously optimizes its action policy ρ according to different objectives, i.e.:

[0108]

[0109] In the formula, Represents the integrated state-action value function; This represents the state-action value function for each performance metric object;

[0110] Optimal strategy It can be obtained through the following formula:

[0111]

[0112] In the formula, This represents the optimal overall state-action value result.

[0113] In this embodiment, the state-action value function of each performance index of the cooperative satellite node is processed using a weighted criterion. Alternatively, other multi-objective function relational criteria can be used for processing, thus synthesizing the state-action value. and the state-action values ​​of each performance metric object The relationship between them is expressed as:

[0114]

[0115] In the formula, w i This represents the positive weight value of the i-th target object. In this embodiment, its specific value is not fixed and can be set according to actual user service needs, link channel conditions, etc.

[0116] According to the Q-learning algorithm, the state-action function value of the i-th performance metric object is calculated as follows:

[0117]

[0118] In the formula, α represents the learning rate in the reinforcement learning algorithm; s′, These represent the future state and actions of the agent during its interaction with the environment.

[0119] In each training phase k, the set of reward values ​​obtained contains multiple elements. The overall reward value is related to the reward value of each performance metric object. Therefore, according to the weighting criterion, the overall reward value is... The corresponding calculation is as follows:

[0120]

[0121] In the formula, the variable r = {1, 2}; ω1, ω2 represent the normalized weight values; FER th It is the frame error rate threshold preset by the ground receiver.

[0122] During the learning and training phase k, each cooperative satellite node S r FER (Frame Error Rate) Sr,k The results were obtained by running T Monte Carlo simulations under Rayleigh slow fading channel conditions using a fast successive cancellation decoding algorithm or other polar code decoding algorithms, where T>10. 6 η o,k This represents the combined throughput efficiency of the two cooperating satellite nodes.

[0123] After running E training cycles, it converges to the final state, based on the combined state-action values ​​and the optimal policy. Determine the optimal action Output NTN coding cooperation system optimized parameter configuration

[0124] In summary, this invention transmits user-generated signals to cooperating nodes via an uplink channel; the cooperating nodes receive the user-generated signals and obtain recovery information through extraction and recovery processing; the cooperating nodes receive, process, and forward signals from each other via a cooperative interaction channel; and the cooperating nodes transmit the recovery information and the signals from the cooperating nodes to the ground destination receiver via a downlink channel. This invention leverages the inherent coding characteristics of polar codes to achieve cooperative communication between space-based and air-based processing and forwarding nodes in NTN, particularly under slow fading channel conditions, simultaneously acquiring coding gain and diversity gain, and employing reinforcement learning methods to jointly optimize the key parameters of code rate and power for cooperating nodes. The information bit error rate at the NTN ground receiver in this invention is significantly reduced compared to the non-cooperative case, and after optimizing the code rate and power parameters under different downlink conditions, the overall performance of the system, including bit error rate and throughput efficiency, is significantly improved.

[0125] It should be noted that the method of this disclosure embodiment can be executed by a single device, such as a computer or server. The method of this embodiment can also be applied to a distributed scenario, where multiple devices cooperate to complete the task. In such a distributed scenario, one of these devices may execute only one or more steps of the method of this disclosure embodiment, and the multiple devices will interact with each other to complete the method described.

[0126] It should be noted that the above description describes some embodiments of this disclosure. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in a different order than that shown in the above embodiments and still achieve the desired result. Furthermore, the processes depicted in the drawings do not necessarily require a specific or sequential order to achieve the desired result. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0127] Example 2

[0128] See Figure 4 Embodiment 2 of the present invention also provides a coding cooperative transmission device in a non-terrestrial network, comprising:

[0129] The collaborative node receiving and processing signal module 001 is used to transmit the user-sent signal to the collaborative node through the uplink channel; the collaborative node receives the user-sent signal and obtains recovery information through extraction and recovery processing.

[0130] The signal transmission module 002 between cooperative nodes is used to receive, process, and forward signals from cooperative nodes through a cooperative interaction channel.

[0131] The signal transmission module 003 between the cooperating node and the ground receiver is used by the cooperating node to transmit the recovery information and the signals of the cooperating nodes to the ground destination receiver through the downlink channel.

[0132] In this embodiment, the cooperative node receiving and processing signal module 001 includes high-, medium-, and low-orbit satellites in the NTN, as well as airships, balloons, and UAV aerial platforms.

[0133] In this embodiment, in the signal transmission module 002 between cooperative nodes, the cooperative interaction channel between cooperative nodes is encoded using polar codes; the encoded codeword expression is:

[0134]

[0135] In the formula, x N The encoded codeword; Both 'v' and 'v' are short codewords; symbols The symbol "|" represents the XOR operation; it represents two short codewords. B is concatenated with v to form a long codeword of length N; N Let be an N×N row permutation matrix.

[0136] In this embodiment, the sub-module for transmitting information via coded cooperation in the signal transmission module 003 from the cooperating node to the ground receiver includes:

[0137] Self-subframe generation submodule 031 is used by cooperating nodes S1 and S2 to generate submatrix G1 and information bit subsequence. Each K1 information bits are encoded into a subframe.

[0138] Self-subframe transmission submodule 032 is used in the first time slot, where the cooperating node S1 transmits the subframe via the downlink. Transmit subframes at power P1 To ground receiver D; cooperative node S2 via downlink Transmit subframes at power P2 The information is transmitted to the ground receiver D; the cooperating node S1 obtains the estimation information of the cooperating node S2 through the cooperative interaction channel; the cooperating node S2 obtains the estimation information of the cooperating node S1 through the cooperative interaction channel.

[0139] Subcode generation submodule 033 is used in the second time slot by cooperating nodes S1 and S2 to generate submatrix G2 and information bit subsequence based on the generation matrix. Encode each of the K2 information bits into a subcode.

[0140] Composite subframe generation submodule 034 is used by cooperative node S1 to re-encode the estimated information of cooperative node S2 into... Will AND subcode Subframes are obtained through XOR operations. Collaborating node S2 re-encodes the estimated information from collaborating node S1 into Will AND subcode Subframes are obtained through XOR operations.

[0141] Composite subframe transmission submodule 035 is used by cooperating node S1 to transmit data via the downlink. Transmit subframes at power P2 To ground receiver D; cooperative node S2 via downlink Transmit subframes at power P1 To ground receiving end D;

[0142] Subframe splicing submodule 036 is used by the ground receiver D to splice subframes sent by the cooperating node S1. Subframes sent by cooperating node S2 The data is spliced ​​together to obtain the spliced ​​signal from cooperating node S1; the ground receiver D transmits the subframes sent by cooperating node S2. Subframes sent by cooperating node S1 Perform splicing to obtain the splicing signal of the cooperating node S2;

[0143] The splicing signal decoding submodule 037 is used by the ground receiver D to decode the splicing signals of cooperating node S1 and cooperating node S2 respectively, so as to obtain the transmission information of cooperating node S1 and cooperating node S2.

[0144] In this embodiment, the signal transmission module 003 of the cooperative node to the ground receiver designs a global performance joint optimization strategy for the NTN polar coding cooperative system based on a reinforcement learning algorithm; and determines the optimal cooperative coding code rate and optimal power allocation parameters through the global performance joint optimization strategy of the NTN polar coding cooperative system.

[0145] The problem that the global performance joint optimization strategy of the NTN polar coding cooperative system needs to solve is expressed as:

[0146]

[0147] In the formula, f i and F oThese represent the objective functions for individual performance metrics and the overall performance metrics of the collaborating nodes, respectively. These are the code rates of cooperating nodes S1 and S2, respectively; P1 and P2 are the subframe signal transmission powers of the two transmission slots, respectively. These are the downlink channel signal-to-noise ratios of the two cooperating nodes S1 and S2, respectively. η represents the frame error rates of the two cooperating nodes S1 and S2, respectively. o The throughput efficiency of the NTN coding cooperative system.

[0148] It should be noted that the information interaction and execution process between the modules of the above system are based on the same concept as the method embodiment in Embodiment 1 of this application, and the resulting technical effects are the same as those in the method embodiment of this application. For details, please refer to the description in the method embodiment shown above in this application, and it will not be repeated here.

[0149] Example 3

[0150] Embodiment 3 of the present invention provides a non-transitory computer-readable storage medium storing program code for a coded cooperative transmission method in a non-terrestrial network. The program code includes instructions for executing the coded cooperative transmission method in a non-terrestrial network according to Embodiment 1 or any possible implementation thereof.

[0151] Computer-readable storage media can be any available medium that a computer can access, or a data storage device such as a server or data center that integrates one or more available media. The available medium can be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., DVDs), or semiconductor media (e.g., solid-state drives, SSDs).

[0152] Example 4

[0153] Embodiment 4 of the present invention provides an electronic device, including: a memory and a processor;

[0154] The processor and the memory communicate with each other via a bus; the memory stores program instructions that can be executed by the processor, and the processor can execute a coded cooperative transmission method in a non-terrestrial network according to Embodiment 1 or any possible implementation thereof by calling the program instructions.

[0155] Specifically, a processor can be implemented in hardware or software. When implemented in hardware, the processor can be a logic circuit, an integrated circuit, etc. When implemented in software, the processor can be a general-purpose processor that reads software code stored in memory. This memory can be integrated into the processor or located outside the processor and exist independently.

[0156] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented, in whole or in part, as a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of the present invention are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable system. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means.

[0157] It is obvious to those skilled in the art that the modules or steps of the present invention described above can be implemented using general-purpose computing systems. They can be centralized on a single computing system or distributed across a network of multiple computing systems. Optionally, they can be implemented using program code executable by a computing system, thereby storing them in a storage system for execution by the computing system. In some cases, the steps shown or described can be performed in a different order than those presented herein, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. Thus, the present invention is not limited to any particular combination of hardware and software.

[0158] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A method for coded cooperation transmission in non-terrestrial networks, the method comprising: The method comprises the following steps: transmitting the user signal to the cooperative nodes through an uplink channel; the cooperative nodes receive the user signal and obtain recovery information through extraction and recovery processing; the cooperative nodes receive and process the signals forwarded from the cooperative nodes through a cooperative interaction channel; the cooperative nodes transmit the recovery information and the signals of the cooperative nodes to the ground receiving end through a downlink channel; the cooperative nodes transmit information through an encoding cooperation mode; the step of transmitting information through the encoding cooperation mode comprises the following steps: The cooperation nodes S1, S2 encode the K1 information bits each into a subsequence of the submatrix G1 of the generator matrix G according to the information bits subsequence ​ In the first time slot, cooperating node S1 communicates via the downlink. Transmit subframes at power P1 To ground receiver D; cooperative node S2 via downlink Transmit subframes at power P2 The information is transmitted to the ground receiver D; the cooperating node S1 obtains the estimation information of the cooperating node S2 through the cooperative interaction channel; the cooperating node S2 obtains the estimation information of the cooperating node S1 through the cooperative interaction channel. In the second time slot, the cooperating nodes S1, S2 encode the information bit subsequence each K2 information bits into a subcode The cooperating node S1 re-encodes the estimated information of the cooperating node S2 into The estimated information of the cooperating node S1 is re-encoded by the cooperating node S2 into The sub-codes w S1 The sub-frames are obtained by an XOR operation The estimated information of the cooperating node S1 is re-encoded by the cooperating node S2 into The estimated information of the cooperating node S1 is re-encoded by the cooperating node S2 into The sub-codes w The sub-frames are obtained by an XOR operation Cooperative node S1 transmits subframes to ground receiving end D through downlink at power P2 Cooperative node S2 transmits subframes to ground receiving end D through downlink at power P1 Cooperative node S1 transmits subframes to ground receiving end D through downlink The ground receiving end D splices the sub-frame transmitted by the cooperative node S1 and the sub-frame transmitted by the cooperative node S2 to obtain the spliced signal of the cooperative node S1; the ground receiving end D splices the sub-frame transmitted by the cooperative node S2 and the sub-frame transmitted by the cooperative node S1 to obtain the spliced signal of the cooperative node S2; the ground receiving end D decodes the spliced signals of the cooperative nodes S1 and S2 respectively to obtain the transmission information of the cooperative nodes S1 and S2.

2. The method of Claim 1, wherein The cooperative nodes comprise high, medium and low orbit satellites, airships, balloons and unmanned aerial vehicle air platforms in the NTN.

3. The method of Claim 2, wherein The cooperative interaction channel between the cooperative nodes adopts polar code for encoding; the expression of the encoded codeword is: where x N is the encoded codeword; and v are short codewords; the symbol denotes the XOR operation; the symbol | denotes the concatenation of two short codewords and v into a long codeword of length N; B N is an N x N row permutation matrix.

4. The method of Claim 3, wherein Based on the reinforcement learning algorithm, a global performance joint optimization strategy of the NTN polar encoding cooperation system is designed; through the global performance joint optimization strategy of the NTN polar encoding cooperation system, the optimal cooperative encoding code rate and the optimal power allocation parameter are determined; The expression of the problem to be solved by the global performance joint optimization strategy of the NTN polar encoding cooperation system is: In the formula, f i and F o respectively represent the single performance index target function and the comprehensive index target function of the cooperation node; respectively are code rates of the cooperation nodes S1 and S2; P1 and P2 respectively are subframe signal transmission powers of the two sending time slots; respectively are downlink channel signal-to-noise ratios of the two cooperation nodes S1 and S2; respectively are frame error rates of the two cooperation nodes S1 and S2; η o is the throughput efficiency of the NTN encoding cooperation system.

5. An apparatus for coded cooperation transmission in non-terrestrial networks, employing the method for coded cooperation transmission in non-terrestrial networks according to any one of claims 1 to 4, characterized in that The method comprises the following steps: The cooperative node receiving and processing signal module is used for transmitting the user signal to the cooperative nodes through an uplink channel; the cooperative nodes receive the user signal and obtain recovery information through extraction and recovery processing; The signal transmission module between the cooperative nodes is used for receiving and processing the signals forwarded from the cooperative nodes through a cooperative interaction channel; The cooperative node signal transmission module to the ground receiving end is used for transmitting the recovery information and the signals of the cooperative nodes to the ground receiving end through a downlink channel.

6. The apparatus for coded cooperation transmission in a non-terrestrial network according to claim 5, wherein, In the cooperative node receiving and processing signal module, the cooperative nodes comprise high, medium and low orbit satellites, airships, balloons and unmanned aerial vehicle air platforms in the NTN.

7. The apparatus for coded cooperation transmission in a non-terrestrial network according to claim 6, wherein, In the signal transmission module between the cooperative nodes, the cooperative interaction channel between the cooperative nodes adopts polar code for encoding; the expression of the encoded codeword is: where x N is the encoded codeword; and v are both short codewords; the symbol represents an exclusive-OR operation; the symbol |" represents the concatenation of two short codewords and v into a long codeword of length N; B N is an N x N row permutation matrix.

8. The apparatus for coded cooperation transmission in non-terrestrial networks according to claim 7, wherein, In the cooperative node signal transmission module to the ground receiving end, the sub-module for transmitting information through an encoding cooperation mode comprises: The self subframe generating submodule is configured to generate, according to the submatrix G1 of the generating matrix and the information bit subsequence Encode the respective K1 information bits into subframes a self-subframe transmission sub-module, configured to, in the first time slot, transmit, by the cooperative node S1, a subframe to the ground receiving end D through a downlink channel at a power P1 a self-subframe transmission sub-module, configured to, in the first time slot, transmit, by the cooperative node S1, a subframe to the ground receiving end D through a downlink channel at a power P1 a self-subframe transmission sub-module, configured to, in the first time slot, transmit, by the cooperative node S1, a subframe to the ground receiving end D through a downlink channel at a power P1 a self-subframe transmission sub-module, configured to, in the first time slot, transmit, by the cooperative node S1, a subframe to the ground receiving end D through a downlink channel at a power P1 a self-subframe transmission sub-module, configured to, in the first time slot, transmit, by the cooperative node S1, a subframe to the ground receiving end D through a downlink channel at a power P1 a subcode generating sub-module, configured to generate, in the second time slot, a subsequence of information bits according to a submatrix G2 of the generating matrix and the information bit sequence encode the respective K2 information bits into subcodes The composite subframe generating submodule is configured to re-encode the estimation information of the cooperation node S2 into The composite subframe generating submodule is configured to re-encode the estimation information of the cooperation node S2 into The composite subframe generating submodule is configured to re-encode the estimation information of the cooperation node S2 into The composite subframe generating submodule is configured to re-encode the estimation information of the cooperation node S2 into The composite subframe generating submodule is configured to re-encode the estimation information of the cooperation node S2 into The composite subframe generating submodule is configured to re-encode the estimation information of the cooperation node S2 into The composite subframe generating submodule is configured to re-encode the estimation information of the cooperation node S2 into The composite subframe generating submodule is configured to re-encode the estimation information of the cooperation node S2 into a composite frame transfer sub-module, for cooperating node S1 to transmit sub-frames to ground receiving end D through downlink at power P2 to ground receiving end D; cooperating node S2 to transmit sub-frames to ground receiving end D through downlink at power P1 to ground receiving end D; The subframe splicing sub-module is configured to splice, by the ground receiving end D, a subframe sent by the cooperation node S1 and a subframe sent by the cooperation node S2 to obtain a splicing signal of the cooperation node S1; and splice, by the ground receiving end D, a subframe sent by the cooperation node S2 and a subframe sent by the cooperation node S1 to obtain a splicing signal of the cooperation node S2 The spliced signal decoding sub-module is used for decoding the spliced signals of the cooperative nodes S1 and S2 respectively by the ground receiving end D to obtain the transmission information of the cooperative nodes S1 and S2.

9. The apparatus for coded cooperation transmission in a non-terrestrial network according to claim 8, wherein, In the cooperative node signal transmission module to the ground receiving end, based on the reinforcement learning algorithm, a global performance joint optimization strategy of the NTN polar encoding cooperation system is designed; through the global performance joint optimization strategy of the NTN polar encoding cooperation system, the optimal cooperative encoding code rate and the optimal power allocation parameter are determined; The expression of the problem to be solved by the global performance joint optimization strategy of the NTN polar encoding cooperation system is: In the formula, f i and F o respectively represent the single performance index target function and the comprehensive index target function of the cooperation node; respectively are code rates of the cooperation nodes S1 and S2; P1 and P2 respectively are subframe signal transmission powers of the two sending time slots; respectively are downlink channel signal-to-noise ratios of the two cooperation nodes S1 and S2; respectively are frame error rates of the two cooperation nodes S1 and S2; η o is the throughput efficiency of the NTN encoding cooperation system.

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