Satellite communication hopping beam resource allocation method and system based on robust precoding

Abstract

The invention belongs to the related technical field of satellite communication, and discloses a satellite communication hopping beam resource allocation method and system based on robust precoding, and the method comprises the steps: determining a candidate hopping beam vector set # imgabs0 # according to the interference degree, and selecting a new set from the set # imgabs1 #, each vector in the new set # imgabs2 at least represents that the mth cell is lighted and the previous m-1 cells are not lighted, the mth cell has the mth priority, the sum of the spectral efficiencies of the lighted cells in the vectors is used as the path length of the vectors, a vector is selected from each new set with the longest total path as the target, an optimized hopping beam matrix is formed, and an optimized hopping beam matrix is formed; according to the method, a pre-coding optimization problem of maximum spectrum efficiency is constructed for each time slot and is solved, a satellite transmitting end pre-coding matrix of the corresponding time slot is obtained, and on the basis of the combination of the hopping beam and the pre-coding technology, the interference between beams is greatly reduced, the spectrum efficiency is improved, and meanwhile, the robustness can also be improved.

Description

Technical Field

[0001] The present invention belongs to the technical field related to satellite communications, and more specifically, relates to a satellite communication beam hopping resource allocation method and system based on robust precoding. Background Art

[0002] With the rapid development of communication technology and the rapid growth of global communication needs, low earth orbit satellite (LEO) systems have occupied an increasingly important position in modern communication networks. In low earth orbit satellite communication systems, beam hopping and precoding technology are considered to be key technical means to improve system capacity and spectrum utilization. Compared with traditional multi-beam technology, beam hopping technology dynamically allocates beam resources, flexibly adjusts the provided capacity to adapt to heterogeneous needs, and enables multiple users to share the same spectrum resources, thereby significantly improving the system's spectrum efficiency. At the same time, precoding technology can effectively eliminate inter-beam interference, optimize signal transmission paths, and further improve the system's spectrum efficiency. Therefore, the combination of beam hopping and precoding technology can improve the spectrum efficiency and capacity of low earth orbit satellite systems.

[0003] There are some studies on combining beam hopping with precoding technology, such as:

[0004] Chinese patent CN115833904B mentions the combination of beam hopping and precoding technology, but the scheme is mainly centered around the goal of achieving low power when planning beam hopping. Interference between cells and within beams is still relatively obvious, and the proposed precoding algorithm is not robust to satellite channels.

[0005] Chinese patent CN110996394B mentions the combination of beam hopping and precoding technology. However, this solution is mainly centered around the purpose of improving service quality when planning beam hopping, and only needs to meet the traffic flow of each cell. It does not directly implement interference suppression strategies, and the proposed precoding algorithm is not robust to satellite channels.

[0006] Therefore, it is necessary to propose a new satellite communication beam hopping resource allocation method to effectively reduce beam interference in communication and improve the robustness of satellite channels. Summary of the invention

[0007] In view of the above defects or improvement needs of the prior art, the present invention provides a satellite communication beam hopping resource allocation method and system based on robust precoding, which aims to solve the technical problems of satellite communication beam interference and robustness.

[0008] To achieve the above object, the present invention provides a satellite communication beam hopping resource allocation method based on robust precoding, which includes:

[0009] Constructing a channel matrix according to satellite communication system configuration information and channel state information;

[0010] Analyze the N within the satellite coverage area C The interference degree between cells is used to determine the candidate beam hopping vector set according to the interference degree. Each candidate beam hopping vector represents N B cells are lit and the interference between each cell is less than the set threshold. B It is the number of beams transmitted by the satellite in the same time slot, and the lighted cells are the cells receiving the beams;

[0011] From the collection Select N C new set, the mth new set Each vector in represents at least lighting up the mth cell and not lighting up the first m-1 cells. The mth cell has the mth priority. The sum of the spectrum efficiencies of the cells lit in the vector is used as the path length of the corresponding vector. With the longest total path as the goal, a vector is selected from each new set to form an optimized beam hopping matrix, which is selected from the new set The vector is used as the lighting state of time slot m in the beam cycle, m = 1, 2, 3, ..., N C ;

[0012] Based on the channel matrix and the optimized beam-hopping matrix, a precoding optimization problem that maximizes the spectrum efficiency is constructed and solved for each time slot to obtain the satellite transmitter precoding matrix for the corresponding time slot.

[0013] Optionally, the candidate beam hopping vector set is determined according to the interference degree. include:

[0014] Calculate the distances between all cells respectively and construct a weight matrix between cells. If the distance between two cells is greater than or equal to the distance threshold, the corresponding two cells have a first weight; otherwise, the corresponding two cells have a second weight.

[0015] Determine a set of candidate beam hopping vectors based on the weight matrix In the collection In the example, any vector lights up N B Every two cells have the first weight.

[0016] Optionally, selecting a vector from each new set with the longest total path as the goal includes:

[0017] Using the Viterbi algorithm, we can re-set The vector optimization is performed step by step in the m-th step optimization reward function is:

[0018] J m (c m,n )=max(J m-1 +L(c m,n ))

[0019] In the formula, J m Represents a new collection The reward of the path obtained after selecting the vector, c m,n For new collection The nth vector in L(c m,n ) is the vector c m,n Reward.

[0020] Optionally, the precoding optimization problem for maximizing spectrum efficiency is constructed and solved for each time slot, and the optimization goal is specifically:

[0021]

[0022] Where W m [t] is the auxiliary variable to be decided for the mth cell in time slot t, w m is the satellite transmitter precoding vector serving the mth cell, A BH [t,m]=1 means that the mth cell is lit in time slot t, H m is the channel matrix of the mth cell, tr() means finding the trace of the matrix, is the noise variance.

[0023] Optionally, the precoding optimization problem for maximizing spectrum efficiency is constructed and solved for each time slot, and the optimization goal is specifically:

[0024]

[0025]

[0026] Where W m [t] is the auxiliary variable to be decided for the mth cell in time slot t, w m is the satellite transmitter precoding vector serving the mth cell, A BH [t,m]=1 means that the mth cell is lit in time slot t, H m is the channel matrix of the mth cell, tr() means finding the trace of the matrix, is the noise variance, α m , μ m They are all auxiliary variables introduced in the solution, and the superscript i represents the number of iterations performed during the solution.

[0027] Optionally, the optimization problem further includes an interruption probability constraint, and the interruption probability constraint includes:

[0028]

[0029] In the formula, γ m [t] is the signal-to-interference-noise ratio of the mth cell in time slot t, Γ m Indicates the set signal-to-interference-noise ratio threshold, p m Indicates the outage probability threshold.

[0030] Optionally, the constructed channel matrix is ​​obtained by considering a phase error and an amplitude error, and both the phase error and the amplitude error satisfy a normal distribution.

[0031] The present invention also provides a satellite communication beam hopping resource allocation system based on robust precoding, which comprises:

[0032] A channel matrix construction unit, used to construct a channel matrix according to satellite communication system configuration information and channel state information;

[0033] Candidate set construction unit, analyze N within the coverage area of ​​the satellite C The interference degree between cells is used to determine the candidate beam hopping vector set according to the interference degree. Each candidate beam hopping vector represents N B cells are lit and the interference between each cell is less than the set threshold. B It is the number of beams transmitted by the satellite in the same time slot, and the lighted cells are the cells receiving the beams;

[0034] Optimize the matrix construction unit for Select N C new set, the mth new set Each vector in represents at least lighting up the mth cell and not lighting up the first m-1 cells. The mth cell has the mth priority. The sum of the spectrum efficiencies of the cells lit in the vector is used as the path length of the corresponding vector. With the longest total path as the goal, a vector is selected from each new set to form an optimized beam hopping matrix, which is selected from the new set The vector is used as the lighting state of time slot m in the beam cycle, m = 1, 2, 3, ..., N C ;

[0035] The solving unit is used to construct and solve a precoding optimization problem for maximizing spectrum efficiency for each time slot based on the channel matrix and the optimized beam hopping matrix, so as to obtain a satellite transmitting end precoding matrix for the corresponding time slot.

[0036] The present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program implements the steps of any of the above methods when executed by a processor.

[0037] The present invention also provides a computer program product, comprising a computer program or instructions, wherein when the computer program or instructions are executed by a processor, the steps of any of the above methods are implemented.

[0038] In general, compared with the prior art, the above technical solutions conceived by the present invention mainly have the following beneficial effects:

[0039] The method proposed in the present invention combines beam hopping with precoding technology. When optimizing the beam hopping matrix, the cells are first combined according to the interference degree between the cells, so that the interference degree between the cells lit by the beam in the same time slot is small, thereby achieving the purpose of reducing the interference between the cells. After determining the candidate beam hopping vector set according to the cell interference degree, further optimization is performed from the candidate set by specific means, that is, N are selected from the candidate vector set. C New collection, new collection Each vector in must light up the mth cell, from each new set A beam hopping vector is selected from the hopping vectors to form a beam hopping matrix, so that each cell is lit at least once in the entire hopping period, and the new set The first m-1 cells are not lit, so that the mth cell can be guaranteed to have the mth priority. At the same time, when selecting the beam hopping vector from the new set, the sum of the spectrum efficiencies of each cell in the vector is used as the path length of the corresponding vector, and a vector is selected from each new set with the longest total path as the goal. This can further increase the spectrum efficiency and achieve the purpose of further reducing beam interference. Finally, after obtaining the optimized beam hopping matrix, a precoding optimization problem that maximizes the spectrum efficiency is constructed and solved. By constructing the precoding optimization problem, the satellite transmitter precoding matrix is ​​obtained, which can increase the spectrum efficiency again and achieve the purpose of further reducing beam interference. Since the scheme is to solve the optimal solution, the robustness of the scheme can be improved. Based on the above combination of beam hopping and precoding technology, the interference between beams is greatly reduced, the spectrum efficiency is improved, and the robustness can also be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 is a schematic diagram of a single-satellite multi-user low-orbit satellite communication system in one embodiment;

[0041] Figure 2 is a flowchart of the steps of a satellite communication beam hopping resource allocation method based on robust precoding in one embodiment of the present invention;

[0042] Figure 3 is a schematic diagram of optimizing in combination with the Viterbi algorithm in one embodiment of the present invention;

[0043] Figure 4 It is a comparison chart of spectrum efficiency under different beam hopping resource allocation schemes;

[0044] Figure 5 It is a graph of the outage probability versus the total spectrum efficiency of the system. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0046] like Figure 1 The figure is a schematic diagram of a single-satellite multi-user low-orbit satellite communication system in an embodiment. The satellite is equipped with N T =N Tx ×N Ty The satellite can generate N B beams to illuminate N C In order to simplify the model, one user is considered in each cell, and each ground user uses a single antenna. Each beam hopping period (BH period for short) consists of N TS time slots, each of which can light up N B cells, and the duration is T, so each BH cycle lasts for N TS ×T.

[0047] The beam hopping matrix (BH matrix for short) is expressed as The BH vector Indicates the lighting status of the cell in the tth time slot, a t,i ∈{0,1} indicates the lighting status of the cell in a specific time slot, i.e., a t,i =1 indicates that cell i is lit in the tth time slot.

[0048] In the tth time slot within the BH period, define a set This set contains the indices of the cells that are lit in this time slot, so the received signal of the i-th cell can be written as: Among them, s i [t] is the signal transmitted by the satellite. is the channel coefficient vector corresponding to the i-th cell in the time slot, represents the precoding matrix, is zero-mean additive Gaussian noise, and its variance is

[0049] The channel matrix can be used If the satellite is equipped with a UPA antenna array, h i [t] can be expressed as in, represents the large-scale fading coefficients of the channel matrix, represents the array response vector, θ and φ represent the elevation angle and azimuth angle of the LOS path respectively. The spectral efficiency of cell i in time slot t can be expressed as: where γ i represents the signal to interference and noise ratio of cell i.

[0050] Based on the above knowledge, the present invention proposes a satellite communication beam hopping resource allocation method and system based on robust precoding to solve the problem of satellite communication beam interference.

[0051] Example 1

[0052] like Figure 2 The figure is a flowchart of the steps of a satellite communication beam hopping resource allocation method based on robust precoding in one embodiment of the present invention, and the steps are described in detail below.

[0053] S1, construct a channel matrix according to the satellite communication system configuration information and channel state information.

[0054] Specifically, the channel matrix can be expressed as the Hadamard product of the channel gain vector and the channel phase vector, that is, Among them, g i represents the channel gain vector, b i represents the radiation vector, θ i represents the channel phase vector.

[0055] In one embodiment, the channel matrix considering the phase error and the amplitude error can be expressed as: In this way, a channel matrix with phase error and amplitude error can be obtained, and each error obeys normal distribution.

[0056] In this way, it can be ensured that subsequent robustness algorithms are studied on the basis of the channel matrix with channel estimation error, which is more suitable for real satellite communication systems.

[0057] S2, analyze the N within the coverage area of ​​the satellite C The interference degree between cells is used to determine the candidate beam hopping vector set according to the interference degree. Each candidate beam hopping vector represents N Bcells are lit and the interference between each cell is less than the set threshold. B The number of beams transmitted by the satellite in the same time slot.

[0058] Specifically, the satellite can transmit N B beams, light up N B The closer the cells lit in the same time slot are, the stronger the communication interference between the cells will be. This step is to calculate the interference degree between the cells and select N cells with interference degree less than the set threshold. B The cells form a candidate vector that can be lit in the same time slot. All cells are traversed to obtain all possible candidate vectors to form a candidate beam hopping vector set. In this way, the calculation time can be greatly reduced and inter-beam interference can be alleviated.

[0059] In specific operations, the candidate beam hopping vector set can be determined as follows:

[0060] Calculate the distances between all cells respectively and construct a weight matrix between cells. If the distance between two cells is greater than or equal to the distance threshold, the corresponding two cells have a first weight; otherwise, the corresponding two cells have a second weight.

[0061] Determine the candidate beam hopping vector set based on the weight matrix In the collection In any vector, the N B Every two cells have the first weight.

[0062] During specific settings, the value "1" may be used as the first weight, and the value "0" may be used as the second weight.

[0063] For example, do the following:

[0064] The inter-cell weight is set according to the cell distance. The specific rule is: the distance d between the center of cell m and the center of cell n m,n When the distance threshold D0 between cells that can be lit in the same time slot is not less than the distance threshold D0, the weight κ(m,n) between cells m and n is set to 1, otherwise the weight κ(m,n) between cells m and n is set to 0. Among them, the distance threshold D0 can be adjusted according to the actual situation, such as D0 = 4R0, R0 represents the cell radius. After setting the weights between each cell, the cells that meet κ(m,n) = 1 in the same time slot are combined to form a candidate BH vector set, that is, gather The cells lit up by each vector in all satisfy the weight conditions.

[0065] S3, from the collection Select N C new set, the mth new set Each vector in represents at least lighting up the mth cell and not lighting up the first m-1 cells. The mth cell has the mth priority. The sum of the spectrum efficiencies of the cells lit in the vector is used as the path length of the corresponding vector. With the longest total path as the goal, a vector is selected from each new set to form an optimized beam hopping matrix, which is selected from the new set The vector is used as the lighting state of time slot m in the beam cycle, m = 1, 2, 3, ..., N C .

[0066] Specifically, the cell lit in each time slot will be arranged according to the priority of the cell. The priority can be determined according to the data rate requirement of the cell, that is, the greater the data rate requirement, the higher the priority. In the present invention, the mth cell is defined as having the mth priority, that is, the mth cell is the cell ranked mth when arranged from large to small according to the priority, and cell 1 has the highest priority, and cell N has the highest priority. C has the lowest priority.

[0067] In specific operations, the Viterbi algorithm can be combined, such as Figure 3 As shown, there are N C Each stage corresponds to a time slot, and the cells that can be lit in that stage are selected. For the mth stage, select the cells from the candidate BH set. All candidate BH vectors that light up the mth cell are selected to form a new vector set, defined as c m,n Representing a collection The candidate BH vector of the nth lit cell in the mth cell, N m Represents a new vector set The number of candidate BH vectors contained in , where different vectors are used as different states, the set Each vector in lights up the mth cell and does not light up the first m-1 cells. In order to obtain the BH matrix with the highest spectral efficiency, the sum of the spectral efficiencies of each state is taken as the path length, such as c m,n The path length L(c m,n ) can be expressed as: In the formula, c m,n,i Represents vector c m,n The i-th cell is lit in the . Different from the traditional Viterbi algorithm that selects the shortest path, this algorithm selects the longest path as the optimal path. m,n After that, the current path reward function is J m (c m,n ), for the first stage, J m(c m,n ) can be expressed as: J m (c m,n )=max(L(c m,n )); For the subsequent stages, J m (c m,n ) can be expressed as: J m (c m,n )=max(J m-1 (c)+L(c m,n )).

[0068] Finally, each candidate vector on the path with the maximum reward is selected to form the optimized BH matrix.

[0069] S4, based on the channel matrix and the optimized beam-hopping matrix, construct and solve the precoding optimization problem that maximizes the spectrum efficiency for each time slot to obtain the satellite transmitter precoding matrix in the corresponding time slot.

[0070] After obtaining the optimized BH matrix, it is combined with the precoding technology. In the present invention, the precoding BH matrix is ​​solved in the form of constructing an optimization function. By constructing a precoding optimization problem that maximizes the spectrum efficiency, the spectrum efficiency of communication can be further improved during precoding and beam interference can be reduced.

[0071] Specifically, the optimization objective of this optimization problem can be expressed as:

[0072]

[0073] Where W m [t] is the auxiliary variable to be decided for the mth cell in time slot t, w m is the satellite transmitter precoding vector serving the mth cell in the current time slot t, A BH [t,m]=1 means that the mth cell is lit in time slot t, H m is the channel matrix of the mth cell, tr() means finding the trace of the matrix, is the noise variance.

[0074] The above problem is solved to obtain the satellite transmitter precoding vector for each lit cell in the current time slot t, to form the satellite transmitter precoding matrix in time slot t, and to control the satellite to transmit communication signals based on the matrix.

[0075] In some embodiments, in order to simplify the solution process, the above non-convex optimization objective can be further converted into a convex form, so that CVX can be used to solve it directly and quickly. Specifically, the approximation method is used to introduce the auxiliary variable α m , so that αm The right is close to the signal-to-interference-noise ratio part of the objective function Another auxiliary variable μ is introduced m , through iterative transformation, μ m The following two convex constraints are satisfied:

[0076] and

[0077] By introducing two auxiliary variables, the objective function is converted into a convex function and two convex constraints are introduced. The converted form is as follows:

[0078]

[0079] The above optimization objectives can be solved directly.

[0080] Specifically, when solving the problem, appropriate constraints can be set, such as power constraints, auxiliary variables W m The positive definite constraint.

[0081] The power constraint can be expressed as:

[0082]

[0083] Where P max Indicates the upper limit of satellite transmission power.

[0084] Auxiliary variable W m The positive definite constraint can be expressed as:

[0085]

[0086] rank(W m [t])=1

[0087] In one embodiment, in addition to the above constraints, an outage probability constraint is added.

[0088] The outage probability constraint can be expressed as:

[0089]

[0090] In the formula, γ m [t] is the signal-to-interference-noise ratio of the mth cell in time slot t, Γ m Indicates the set signal-to-interference-noise ratio threshold, p m Indicates the outage probability threshold.

[0091] By setting the outage probability constraint, the robustness of the resource allocation method can be further adjusted.

[0092] The interruption probability constraint is non-convex and the solution is complex. Furthermore, in order to simplify the solution, the Bernstein inequality can be used to deal with the probability constraint. In order to apply the Bernstein inequality, the interruption probability constraint needs to be equivalently transformed so that it satisfies the expression form of the Bernstein inequality. Then, the reformulated interruption probability constraint is transformed through the Bernstein inequality, thus converting the interruption probability constraint into a convex constraint.

[0093] The following uses the existing beam hopping method combined with precoding and the traditional MMSE digital precoding as a comparison to further verify the beneficial results that can be achieved by the satellite communication beam hopping resource allocation method based on robust precoding provided by the embodiment of the present invention compared with the prior art.

[0094] like Figure 4 The figure shows a comparison of the total spectrum efficiency of the system within a hopping period of a resource allocation method in an embodiment. The parameter settings are as follows: the satellite altitude is 300 km, the transmitting antenna is N T =2×2, center frequency 30GHz, bandwidth 10MHz, satellites light up 4 beams at the same time, 19 ground cells, number of time slots in a hopping cycle is 32, and cell radius is 52.49km. Figure 4 In the figure, the horizontal axis represents the maximum transmission power in W, and the vertical axis represents the total spectrum efficiency of the system within the hopping period in bps / Hz. Figure 4 Three relationships between the total system spectral efficiency and the maximum transmission power obtained by combining three beam hopping methods with precoding are provided, namely: the traditional beam hopping method combined with precoding, the beam hopping scheme of the present application combined with traditional precoding, and the satellite communication beam hopping resource allocation method based on robust precoding of the present application. It can be seen from the figure that compared with the traditional beam hopping method combined with precoding and the traditional precoding method, the satellite communication beam hopping resource allocation method based on robust precoding of the present application has higher total system spectral efficiency in low-orbit satellite communication systems.

[0095] In addition, in order to further verify the robustness of the satellite communication beam hopping resource allocation method based on robust precoding provided by the embodiment of the present invention, Figure 5 In the figure, the horizontal axis represents the required minimum signal-to-interference-noise ratio in dB, and the vertical axis represents the total spectrum efficiency of the system within the hopping period in bps / Hz. Figure 5 The relationship between the total spectrum efficiency of the system and the required minimum signal-to-interference-noise ratio under different outage probabilities and perfect channel state information is provided. Figure 5It can be seen that when considering the interruption probability, the algorithm performance decreases as the required minimum signal to noise ratio increases, and the higher the interruption probability, the greater the system spectrum efficiency. This is because a larger interruption probability means that more resource blocks are considered unavailable at a given time, and during the optimization process, the resource optimization strategy will give priority to allocating resources to cells with higher signal to noise ratios to ensure effective transmission. In this way, the system may make more efficient use of available resources, thereby improving the overall transmission rate of the system. At the same time, in the robust precoding design, in order to meet the larger interruption probability constraint, the precoding optimization process will choose to perform more active resource allocation and power allocation in cells with higher signal to noise ratios. This strategy improves the transmission rate of the system through more efficient resource allocation while meeting the interruption probability constraint, thereby verifying the robustness of the precoding in this embodiment.

[0096] Example 2

[0097] The present invention also relates to a satellite communication beam hopping resource allocation system based on robust precoding, comprising:

[0098] A channel matrix construction unit, used to construct a channel matrix according to satellite communication system configuration information and channel state information;

[0099] Candidate set construction unit, analyze N within the coverage area of ​​the satellite C The interference degree between cells is used to determine the candidate beam hopping vector set according to the interference degree. Each candidate beam hopping vector represents N B cells are lit and the interference between each cell is less than the set threshold. B It is the number of beams transmitted by the satellite in the same time slot, and the lighted cells are the cells receiving the beams;

[0100] Optimize the matrix construction unit for Select N C new set, the mth new set Each vector in represents at least lighting up the mth cell and not lighting up the first m-1 cells. The mth cell has the mth priority. The sum of the spectrum efficiencies of the cells lit in the vector is used as the path length of the corresponding vector. With the longest total path as the goal, a vector is selected from each new set to form an optimized beam hopping matrix, which is selected from the new set The vector is used as the lighting state of time slot m in the beam cycle, m = 1, 2, 3, ..., N C ;

[0101] The solving unit is used to construct and solve a precoding optimization problem for maximizing spectrum efficiency for each time slot based on the channel matrix and the optimized beam hopping matrix, so as to obtain a satellite transmitting end precoding matrix for the corresponding time slot.

[0102] Among them, each unit can implement the corresponding steps in Example 1. For details, please refer to the above introduction and will not be repeated here.

[0103] Example 3

[0104] The present invention also relates to a computer-readable storage medium having a computer program stored thereon, and the computer program implements the steps of the above method when executed by a processor.

[0105] Specifically, the memory may include a high-speed random access memory, and may also include a non-volatile memory, such as a hard disk, an internal memory, a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card (Flash Card), at least one disk storage device, a flash memory device, or other volatile solid-state storage devices.

[0106] Example 4

[0107] The embodiment of the present invention provides a computer program product or a computer program, which includes computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions, so that the computer device performs the steps of the method of the above embodiment of the present invention.

[0108] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification. It should be noted that "in one embodiment", "for example", "for example", etc. of the present invention are intended to illustrate the present invention, rather than to limit the present invention.

[0109] The above embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent application. It should be pointed out that, for those of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention.

Claims

1. A satellite communication beam hopping resource allocation method based on robust precoding, characterized in that: include: Constructing a channel matrix according to satellite communication system configuration information and channel state information; Analyze the N within the satellite coverage area C The interference degree between cells is used to determine the candidate beam hopping vector set according to the interference degree. Each candidate beam hopping vector represents N B cells are lit and the interference between each cell is less than the set threshold. B It is the number of beams transmitted by the satellite in the same time slot, and the lighted cells are the cells receiving the beams; From the collection Select N C new set, the mth new set Each vector in represents at least lighting up the mth cell and not lighting up the first m-1 cells. The mth cell has the mth priority. The sum of the spectrum efficiencies of the cells lit in the vector is used as the path length of the corresponding vector. With the longest total path as the goal, a vector is selected from each new set to form an optimized beam hopping matrix, which is selected from the new set The vector is used as the lighting state of time slot m in the beam cycle, m = 1, 2, 3, ..., N C ; Based on the channel matrix and the optimized beam-hopping matrix, a precoding optimization problem that maximizes the spectrum efficiency is constructed and solved for each time slot to obtain the satellite transmitter precoding matrix for the corresponding time slot.

2. The satellite communication beam hopping resource allocation method based on robust precoding according to claim 1, characterized in that: The candidate beam hopping vector set is determined according to the interference degree. include: Calculate the distances between all cells respectively and construct a weight matrix between cells. If the distance between two cells is greater than or equal to the distance threshold, the corresponding two cells have a first weight; otherwise, the corresponding two cells have a second weight. Determine a set of candidate beam hopping vectors based on the weight matrix In the collection In the example, any vector lights up N B Every two cells have the first weight.

3. The satellite communication beam hopping resource allocation method based on robust precoding according to claim 1, characterized in that: The method of selecting a vector from each new set with the longest total path as the goal includes: Using the Viterbi algorithm, we can re-set The vector optimization is performed step by step in the m-th step optimization reward function is: I m (c m,n )=max(J m-1 +L(c m,n )) In the formula, J m Represents a new collection The reward of the path obtained after selecting the vector, c m,n For new collection The nth vector in L(c m,n ) is the vector c m,n Reward.

4. The satellite communication beam hopping resource allocation method based on robust precoding according to claim 1, characterized in that: The constructed channel matrix is ​​obtained by considering the phase error and the amplitude error, and both the phase error and the amplitude error satisfy the normal distribution.

5. The satellite communication beam hopping resource allocation method based on robust precoding according to any one of claims 1 to 4, characterized in that: The precoding optimization problem of maximizing spectrum efficiency is constructed and solved for each time slot, and its optimization goal is specifically: Where W m [t] is the auxiliary variable to be decided for the mth cell in time slot t, w m is the satellite transmitter precoding vector serving the mth cell, A BH [t,m]=1 means that the mth cell is lit in time slot t, H m is the channel matrix of the mth cell, tr() means finding the trace of the matrix, is the noise variance.

6. The satellite communication beam hopping resource allocation method based on robust precoding according to any one of claims 1 to 4, characterized in that: The precoding optimization problem of maximizing spectrum efficiency is constructed and solved for each time slot, and its optimization goal is specifically: Where W m [t] is the auxiliary variable to be decided for the mth cell in time slot t, w m is the satellite transmitter precoding vector serving the mth cell, A BH [t,m]=1 means that the mth cell is lit in time slot t, H m is the channel matrix of the mth cell, tr() means finding the trace of the matrix, is the noise variance, α m , μ m They are all auxiliary variables introduced in the solution, and the superscript i represents the number of iterations performed during the solution.

7. The satellite communication beam hopping resource allocation method based on robust precoding according to any one of claims 1 to 4, characterized in that: The optimization problem also includes an interruption probability constraint, and the interruption probability constraint includes: In the formula, γ m [t] is the signal-to-interference-noise ratio of the mth cell in time slot t, Γ m Indicates the set signal-to-interference-noise ratio threshold, p m Indicates the outage probability threshold.

8. A satellite communication beam hopping resource allocation system based on robust precoding, characterized in that: include: A channel matrix construction unit, used to construct a channel matrix according to satellite communication system configuration information and channel state information; Candidate set construction unit, analyze N within the coverage area of ​​the satellite C The interference degree between cells is used to determine the candidate beam hopping vector set according to the interference degree. Each candidate beam hopping vector represents N B cells are lit and the interference between each cell is less than the set threshold. B It is the number of beams transmitted by the satellite in the same time slot, and the lighted cells are the cells receiving the beams; Optimize the matrix construction unit for Select N C new set, the mth new set Each vector in represents at least lighting up the mth cell and not lighting up the first m-1 cells. The mth cell has the mth priority. The sum of the spectrum efficiencies of the cells lit in the vector is used as the path length of the corresponding vector. With the longest total path as the goal, a vector is selected from each new set to form an optimized beam hopping matrix, which is selected from the new set The vector is used as the lighting state of time slot m in the beam cycle, m = 1, 2, 3, ..., N C ; The solving unit is used to construct and solve a precoding optimization problem for maximizing spectrum efficiency for each time slot based on the channel matrix and the optimized beam hopping matrix, so as to obtain a satellite transmitting end precoding matrix for the corresponding time slot.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer program product comprising a computer program or instructions, characterized in that When the computer program or instruction is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

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