A spaceborne four-channel Ka-band data transmission channel system

Abstract

The application discloses a kind of satellite-borne four-channel Ka frequency band data transmission channel systems, it is related to satellite communication technical field, including, the original spectrum data of acquisition Ka frequency band inner frequency point, synchronous reception interference hot area database, construct original spectrum matrix, and mark interference area, generate spectrum map with interference mark;With interference mark spectrum map input pre-trained convolutional neural network, output each frequency band interference probability, and identify safe frequency band, and safe frequency band is segmented into micro sub-band, and the optimization allocation scheme is optimized by Q-learning algorithm, and the optimized spectrum configuration table is generated;According to bandwidth parameter in the optimized spectrum configuration table, dynamically adjust modulation mode, and high-speed AOS data is blocked according to frame, and network coding check package is generated in combination with channel allocation strategy in the optimized spectrum configuration table.The application improves the spectrum utilization, communication reliability and overall performance of satellite-borne Ka frequency band data transmission system under dynamic environment.

Description

Technical Field

[0001] This invention relates to the field of satellite communication technology, and in particular to a spaceborne four-channel Ka-band data transmission channel system. Background Technology

[0002] With the continuous advancement of satellite communication technology, especially its increasingly widespread application in the Ka band (26.5–40 GHz), inter-satellite link communication systems have been developed. Currently, Ka-band data transmission channel technology mainly relies on key technologies such as multi-channel parallel transmission, adaptive modulation and coding (AMC), and dynamic resource scheduling. To improve data transmission rate and reliability, researchers have developed various spectrum sensing methods to identify available spectrum resources and adopted advanced modulation and coding schemes (such as QPSK, 16APSK, etc.) to adapt to different channel conditions. In addition, network coding technology has also been introduced into space communication protocols to enhance the robustness and efficiency of data transmission. In particular, when dealing with interference problems in complex electromagnetic environments, traditional approaches typically rely on predefined spectrum allocation strategies or simple energy detection algorithms to avoid known interference sources.

[0003] While existing research has attempted to improve spectrum management and resource scheduling through machine learning and artificial intelligence, most solutions have not yet fully achieved end-to-end closed-loop control from spectrum sensing, modeling, decision-making to transmission. For example, although convolutional neural networks are used for spectrum state prediction and interference area identification, their effectiveness is significantly limited in practical applications, especially in spaceborne environments, due to constraints on computing resources and real-time performance. Furthermore, existing inter-satellite Ka-link communication systems generally employ fixed or semi-fixed modulation schemes, failing to dynamically adjust according to channel quality. This not only affects system throughput but also reduces its anti-interference capability. Summary of the Invention

[0004] In view of the aforementioned existing problems, the present invention is proposed.

[0005] Therefore, the present invention provides a spaceborne four-channel Ka-band data transmission channel system that solves the problems of low spectrum utilization efficiency and weak anti-interference capability of existing spaceborne communication systems.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0007] This invention provides a spaceborne four-channel Ka-band data transmission channel system, which includes a spectrum sensing module that collects raw spectrum data of frequency points within the Ka-band, synchronously receives an interference hotspot database, constructs an original spectrum matrix, marks interference areas, and generates a spectrum map with interference markings.

[0008] The spectrum optimization module inputs the spectrum map with interference markers into a pre-trained convolutional neural network, outputs the interference probability, identifies safe frequency bands, divides the safe frequency bands into micro sub-bands, optimizes the allocation scheme through the Q-learning algorithm, and generates an optimized spectrum configuration table.

[0009] The dynamic modulation module dynamically adjusts the modulation mode according to the bandwidth parameters in the optimized spectrum configuration table, and divides the high-speed AOS data into blocks by frame, and generates network coding check packets in combination with the channel allocation strategy in the optimized spectrum configuration table.

[0010] The link transmission module broadcasts network encoding verification packets to the relay satellite via the inter-satellite Ka link. The relay satellite reconstructs the data according to the network encoding rules, and decodes and verifies the CRC of the reconstructed data.

[0011] As a preferred embodiment of the spaceborne four-channel Ka-band data transmission channel system of the present invention, the original spectrum data includes signal amplitude and signal phase.

[0012] As a preferred embodiment of the spaceborne four-channel Ka-band data transmission channel system of the present invention, the specific steps for constructing the original spectrum matrix, marking interference areas, and generating a spectrum map with interference markings are as follows:

[0013] Construct the original spectrum matrix based on the signal amplitude and signal phase;

[0014] Based on the interference hotspot database, interference is marked in the original spectrum matrix through dual judgment to generate interference mark vectors;

[0015] The original spectrum matrix is ​​fused with the interference marker vector to generate a spectrum map with interference markers.

[0016] As a preferred embodiment of the spaceborne four-channel Ka-band data transmission system described in this invention, the steps of inputting the spectrum map with interference markers into a pre-trained convolutional neural network, outputting the interference probability of each frequency band, and identifying safe frequency bands are as follows.

[0017] Spectral feature data is extracted from the spectrum map with interference markers, and the spectrum feature data is standardized to generate a standardized feature matrix.

[0018] Collect historical spectrum maps with interference markers and use them to train a convolutional neural network;

[0019] The standardized feature matrix is ​​input into the trained convolutional neural network to generate interference probabilities;

[0020] A safety threshold is set based on historical interference probabilities. When the interference probability is less than or equal to the safety threshold, the frequency band is determined to be safe.

[0021] As a preferred embodiment of the spaceborne four-channel Ka-band data transmission channel system described in this invention, the specific steps for dividing the secure frequency band into micro-subbands are as follows:

[0022] Collect the highest modulation order, calculate the minimum bandwidth, and obtain the sub-bandwidth;

[0023] The safe frequency band is divided into subbands based on the total width of the safe frequency band and the width of the subband.

[0024] As a preferred embodiment of the spaceborne four-channel Ka-band data transmission channel system of the present invention, the steps for optimizing the allocation scheme and generating an optimized spectrum configuration table using the Q-learning algorithm are as follows:

[0025] Measure the signal-to-noise ratio, interference power, and channel coherence bandwidth at the center frequency of the sub-band, and generate a sub-band state parameter table;

[0026] Based on the subband state parameter table, an initial Q-learning table is constructed, and the policy optimization iteration is performed through the Q-learning algorithm to generate an optimized spectrum configuration table.

[0027] As a preferred embodiment of the spaceborne four-channel Ka-band data transmission channel system of the present invention, the specific steps for dynamically adjusting the modulation scheme according to the bandwidth parameters in the optimized spectrum configuration table are as follows:

[0028] The bandwidth parameters of the sub-bands are extracted from the optimized spectrum configuration table, and a mapping rule between the bandwidth parameters and the modulation order is constructed.

[0029] Based on the mapping rules, the modulation scheme is assigned to the sub-band, and a modulation parameter configuration table is generated.

[0030] As a preferred embodiment of the spaceborne four-channel Ka-band data transmission channel system described in this invention, the specific steps for dividing high-speed AOS data into frames and generating network-coded check packets by combining the channel allocation strategy in the optimized spectrum configuration table are as follows.

[0031] Acquire high-speed AOS data streams and divide them into coded units to generate raw data block sequences;

[0032] Extract channel priorities from the optimized spectrum configuration table, allocate raw data blocks from the raw data block sequence according to channel priorities, and generate network coding check packets.

[0033] As a preferred embodiment of the spaceborne four-channel Ka-band data transmission channel system described in this invention, the specific steps for broadcasting the encoded verification packet to the relay satellite via the inter-satellite Ka link are as follows:

[0034] Query nearby satellites, obtain link margin, and select relay satellites based on the link margin;

[0035] Based on the optimized spectrum configuration table and the modulation parameter configuration table, configure the broadcast frequency band and obtain the transmission frequency;

[0036] Based on the transmission frequency, network code check packets are sent to relay satellites using inter-satellite Ka links.

[0037] As a preferred embodiment of the spaceborne four-channel Ka-band data transmission channel system described in this invention, the relay satellite reconstructs the data according to network coding rules, decodes the reconstructed data, and verifies the CRC. The specific steps are as follows:

[0038] The relay satellite receives the network coded verification packet, reconstructs the data block sequence using the continuous phase detection algorithm, recovers lost data blocks, and generates a complete data block group.

[0039] Based on the complete data block group, calculate the CRC-16 value of the data block and generate the verification status code.

[0040] The beneficial effects of this invention are as follows: By collecting the amplitude and phase of Ka-band signals to construct a spectrum map with interference markers, and using a convolutional neural network to intelligently identify the spectrum interference status, accurate identification of safe frequency bands in complex electromagnetic environments is achieved; furthermore, by combining the Q-learning algorithm to dynamically optimize the allocation of sub-band resources, the resource scheduling capability and transmission efficiency of the inter-satellite communication system under conditions of multiple interferences and time-varying channels are improved. These two core steps respectively solve the problems of spectral response lag and rigid resource allocation in existing technologies, improving the spectrum utilization, communication reliability, and overall performance of the spaceborne Ka-band data transmission system in dynamic environments. Attached Figure Description

[0041] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0042] Figure 1 This is a schematic diagram of a spaceborne four-channel Ka-band data transmission system.

[0043] Figure 2 The flowchart for generating the subband state parameter table.

[0044] Figure 3 A flowchart for constructing an optimized spectrum configuration table.

[0045] Figure 4 This is a flowchart for generating network encoding verification packets. Detailed Implementation

[0046] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0047] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0048] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0049] Reference Figures 1-4 As one embodiment of the present invention, this embodiment provides a spaceborne four-channel Ka-band data transmission channel system, comprising the following steps:

[0050] The spectrum sensing module collects raw spectrum data of each frequency point within the Ka band, synchronously receives the interference hot zone database, constructs the raw spectrum matrix, marks the interference areas, and generates a spectrum map with interference markings.

[0051] The raw spectrum data of each frequency point within the Ka band is collected, including signal amplitude and signal phase, and the interference hot zone database is received synchronously.

[0052] Furthermore, the starting frequency of the satellite receiver is set to 26.5 GHz, the ending frequency to 40 GHz, and the scan step to 50 MHz, generating a scan frequency list. Each frequency point is traversed according to the scan frequency list, and the RF signal is down-converted to a 1.5 GHz intermediate frequency using a superheterodyne mixer. The signal amplitude and phase are measured using an I / Q demodulator. Data files uploaded by the ground station are received via an S-band telemetry link, and the interference area definition fields in the data files, including the starting frequency, ending frequency, and interference level, are parsed to generate an interference hotspot database.

[0053] Construct the original spectrum matrix, mark the interference regions, and generate a spectrum map with interference markings;

[0054] The original spectrum matrix expression is:

[0055] ;

[0056] in, The original spectrum matrix, For frequency, For signal amplitude, For signal phase, For timestamps, For row-dimensional indexes;

[0057] The original expression for the row dimension of the spectrum matrix is:

[0058] ;

[0059] in, The row dimension of the original spectrum matrix. The starting frequency, For the termination frequency, For scanning steps;

[0060] Based on the interference hotspot database, interference is marked in the original spectrum matrix through dual judgment to generate interference mark vectors;

[0061] For example, when the amplitude value is greater than -90 dB / mW, it is marked as interference; when the frequency falls into any region of the interference hotspot database, it is marked as interference, and an interference tag vector is generated.

[0062] The original spectrum matrix is ​​fused with the interference marker vector to generate a spectrum map with interference markers.

[0063] Furthermore, the interference marker vector is added as the fifth column to the original spectrum matrix, and the row with a value of 1 in the fifth column corresponds to the interference region, thus generating a spectrum map with interference markers.

[0064] The spectrum optimization module inputs the spectrum map with interference markers into a pre-trained convolutional neural network, outputs the interference probability of each frequency band, identifies safe frequency bands, divides the safe frequency bands into micro sub-bands, optimizes the allocation scheme through the Q-learning algorithm, and generates an optimized spectrum configuration table.

[0065] Spectral feature data is extracted from the spectrum map with interference markers, and the spectrum feature data is standardized to generate a standardized feature matrix.

[0066] Furthermore, the first four columns of the spectrum map, including frequency, amplitude, phase, and timestamp, are extracted as spectrum feature data. The fifth column, interference marker, is used as a verification label. The spectrum feature data is then standardized to generate a standardized feature matrix.

[0067] Collect historical spectrum maps with interference markers and use them to train a convolutional neural network;

[0068] Furthermore, the first four columns of the historical interference-marked spectrum map are used as spectral feature data, and the fifth column of interference markers is used as validation labels. The spectral feature data is standardized to ensure a normal distribution. A convolutional neural network architecture with three convolutional layers and two fully connected layers is constructed, with each convolutional layer using a 3×3 kernel size and ReLU activation function. Backpropagation is used to update the weight parameters of the convolutional neural network, and gradient descent is used to minimize the binary cross-entropy loss function. An early stopping strategy is used during training to prevent overfitting; training is terminated when the validation set accuracy no longer improves after three consecutive training epochs. Finally, convolutional neural network weight parameters that can output the interference probability at each frequency point based on the input standardized feature matrix are obtained.

[0069] The standardized feature matrix is ​​input into the trained convolutional neural network to generate interference probabilities;

[0070] Furthermore, the expression for the three-layer convolution operation is as follows:

[0071] ;

[0072] ;

[0073] ;

[0074] in, This is the feature map output by the first convolutional layer. This is the feature map output by the second convolutional layer. This is the feature map output by the third convolutional layer. This is the weight matrix of the first layer convolution kernel. This is the weight matrix of the second layer convolution kernel. This is the weight matrix of the third layer convolution kernel. This is the bias vector for the first layer. This is the bias vector for the second layer. This is the bias vector for the third layer. To standardize the characteristic moments, To modify the activation function of the linear unit;

[0075] The expression for the output interference probability of a fully connected layer is:

[0076] ;

[0077] in, For the probability of interference, It is the Sigmoid activation function. This is the weight matrix of the fully connected layer. This is the bias vector for the fully connected layer. For flattening operation.

[0078] A safety threshold is set based on historical interference probabilities. When the interference probability is less than or equal to the safety threshold, the frequency band is determined to be safe.

[0079] Furthermore, a safety threshold is set based on the historical interference probability. For example, if the safety threshold is 0.1, all frequency points are traversed. When the interference probability is less than or equal to the safety threshold, it is marked as safe with a value of 1. When the interference probability is greater than the safety threshold, it is marked as unsafe with a value of 0. All continuous index intervals that satisfy the condition that the safety value of a frequency point is equal to 1 and the safety value of the next frequency point is also equal to 1 are found as safe frequency bands. The physical frequency range is then extracted to generate safe frequency bands.

[0080] Collect the highest modulation order, calculate the minimum bandwidth, and obtain the sub-bandwidth;

[0081] Furthermore, the highest supported modulation order is read from the onboard modem, and the minimum bandwidth required to meet the highest modulation order is calculated, expressed as:

[0082] ;

[0083] in, For minimum bandwidth, The system's nominal bit rate, The roll-off factor, The modulation order;

[0084] Based on the minimum bandwidth required to meet the highest-order modulation requirement, the sub-band width is set to an integer multiple of the minimum bandwidth, for example, the sub-band width is set to twice the minimum bandwidth;

[0085] Furthermore, the highest modulation order stored in the onboard modem is queried, and the system nominal code rate and roll-off factor are obtained. Based on the highest modulation order, system nominal code rate and roll-off factor, the minimum bandwidth calculation operation is performed, and an integer multiple greater than or equal to the minimum bandwidth is selected as the subband width.

[0086] The secure frequency band is divided into sub-bands based on the total bandwidth and the sub-band width;

[0087] Furthermore, the total width of the safe frequency band is obtained, and the number of subbands that can be divided is calculated based on the subband width to generate continuous subbands.

[0088] Measure the signal-to-noise ratio, interference power, and channel coherence bandwidth at the center frequency of the sub-band, and generate a sub-band state parameter table;

[0089] Furthermore, the spectrum analyzer is first started and configured in frequency sweep mode. The receiver port of the spectrum analyzer is connected to the output interface of the onboard RF front-end. The scan range is set to cover all micro-subbands generated by the safe band segmentation operation. For the center frequency of each micro-subband, the spectrum analyzer automatically performs three independent scans. The first scan captures the signal power spectral density distribution, and the signal-to-noise ratio is calculated by the difference between the peak power and the floor noise. The second scan activates the interference detection algorithm, and after excluding the main signal power, the integral value of the residual spectral energy is calculated as the interference power. The third scan uses a broadband linear frequency modulated signal for excitation, and the channel coherence bandwidth is determined by the zero-point interval of the autocorrelation function of the received signal. The results of each scan are recorded in real time in the measurement log buffer, forming a temporary dataset containing a frequency index field. After completing the traversal of all micro-subbands, the frequency index field, signal-to-noise ratio field, interference power field, and channel coherence bandwidth field are extracted from the temporary dataset and arranged in ascending order of frequency to generate a structured table. The structured table contains four columns of data entities: the first column is the physical coordinates of the center frequency of the sub-band, the second column is the signal-to-noise ratio, the third column is the interference power, and the fourth column is the channel coherence bandwidth. The output table is named the sub-band state parameter table.

[0090] Based on the sub-band state parameter table, an initial Q-learning table is constructed, and the policy optimization iteration is performed through the Q-learning algorithm to generate an optimized spectrum configuration table.

[0091] Furthermore, during the initialization process, all data entries in the subband state parameter table are fully read, and four parameters are extracted: subband center frequency coordinates, signal-to-noise ratio, interference power, and channel coherence bandwidth. A three-dimensional matrix data structure is then established based on these four parameters. The matrix row indices strictly correspond to the subband number sequence, the column indices correspond to the state type classification, and the depth index corresponds to the sampling point number in the time dimension. Each matrix unit stores the subband state quantization result at a specific sampling time, forming the underlying data framework of the initial Q-learning table.

[0092] The Q-learning algorithm is initiated for strategy optimization and iterative process. The state space is defined as the output value of the channel quality assessment function, which is generated by a weighted algorithm from the signal-to-noise ratio and interference power in the sub-band state parameter table. The action space is defined as the complete set of channel allocation strategies, including the four channel combination modes supported by the onboard four-channel Ka-band data transmission channel system. During each iteration, when selecting an action, a standard ε-greedy strategy balances exploration and utilization, generating a random number and comparing it with a fixed coefficient ε. If the random number is less than or equal to ε, a channel allocation strategy is randomly selected from the action space; otherwise, the action number corresponding to the channel allocation strategy with the largest Q value in the current three-dimensional matrix is ​​selected. After executing the selected action, the transmission success rate of the inter-satellite link is monitored, and the Bellman equation is used to update the Q-value storage unit in the three-dimensional matrix.

[0093] After completing a fixed number of iterations, the optimization process is terminated. The storage cells associated with each sub-band number in the three-dimensional matrix are scanned row by row to locate the position of the maximum Q value and parse the corresponding channel allocation strategy action number. The three elements of sub-band number, channel allocation strategy action number and center frequency point physical coordinates are mapped into structured data entries and arranged in ascending order of center frequency point physical coordinates to generate an optimized spectrum configuration table.

[0094] The dynamic modulation module dynamically adjusts the modulation mode according to the bandwidth parameters in the optimized spectrum configuration table, and divides the high-speed AOS data into blocks by frame, and generates network coding check packets in combination with the channel allocation strategy in the optimized spectrum configuration table.

[0095] The bandwidth parameters of the sub-bands are extracted from the optimized spectrum configuration table, and a mapping rule between the bandwidth parameters and the modulation order is constructed.

[0096] Furthermore, the optimized spectrum configuration table is traversed, and the combination of the sub-band number field and bandwidth parameter field recorded in the table is read row by row. Simultaneously, the modulation configuration reference table in the non-volatile memory of the onboard modem is loaded. The modulation configuration reference table contains three columns: lower limit of bandwidth interval, upper limit of bandwidth interval, and corresponding modulation order. For the bandwidth parameter of each sub-band record, a full table scan of the modulation configuration reference table is performed. When the bandwidth parameter is within the range of the lower limit and upper limit of the bandwidth interval of a certain row of the modulation configuration reference table, the modulation order is extracted.

[0097] Based on the mapping rules, the modulation scheme is assigned to the sub-band, and a modulation parameter configuration table is generated;

[0098] Specifically, an intermediate mapping dataset is established, containing three columns: the first column is the sub-band number of the optimized spectrum configuration table, the second column is the bandwidth parameter of the optimized spectrum configuration table, and the last column is the modulation order matched by the modulation configuration reference table. After traversing all sub-bands, the intermediate mapping dataset is sorted in ascending order by sub-band number to form a modulation parameter configuration table.

[0099] Acquire high-speed AOS data streams and divide them into coded units to generate raw data block sequences;

[0100] Furthermore, the 1553B bus interface of the onboard data management unit is activated to receive the high-speed AOS data stream bit sequence from the satellite platform payload in real time. The buffer management strategy of the bus interface is configured as a cyclic coverage mode, and the receive buffer threshold is set to twice the maximum length of the AOS transmission frame. When the amount of data in the buffer reaches the receive buffer threshold, the protocol parsing engine is triggered to scan the high-speed AOS data bit sequence, identify the fixed-length synchronization code characteristics of the AOS transmission frame, and locate the start position of the main frame header. The synchronization code field, frame count field, and frame length indication field in the main frame header are extracted, and the physical boundary of the current AOS transmission frame is determined based on the frame length indication field. The payload area after the main frame header is stripped, and the operation control field and frame error control field in the main frame header are retained as protocol metadata. The payload area is cut into data segment entities of fixed size, and each data segment entity is appended with corresponding protocol metadata to form a high-speed AOS data stream. The modulation order digital segment recorded in the modulation parameter configuration table is loaded, and the coding block size mapping table of the onboard memory is queried. The coding block size mapping table stores the correspondence between the modulation order and the maximum coded unit length. Based on the current modulation order and the matching coded block size mapping table, the target length of the coded unit is determined. When the high-speed AOS data stream length exceeds the target length, a secondary segmentation operation is performed to generate a sequence of sub-data units; when the high-speed AOS data stream length is less than the target length, idle bytes are padded to the target length. A globally unique index number is assigned to each coded unit, and the index number field, protocol metadata field, and data unit field are combined to form a three-column structured record. All records are arranged in ascending order of index number to generate the original data block sequence.

[0101] Extract channel priorities from the optimized spectrum configuration table, allocate raw data blocks in the raw data block sequence according to channel priorities, and generate network coding check packets;

[0102] Furthermore, the data storage structure of the spectrum configuration table is optimized, and the channel allocation strategy encoding field of all rows is read. The channel allocation strategy encoding field consists of four binary digits, each corresponding to the priority status of a physical transmission channel in the onboard four-channel Ka-band data transmission channel system. According to the binary weighting parsing rules, the highest weight bit represents the priority of physical transmission channel one, the second highest weight bit represents the priority of physical transmission channel two, and so on, down to the lowest weight bit representing the priority of physical transmission channel four. A higher priority indicates a higher priority, generating a priority ranking list for physical transmission channels.

[0103] The raw data block allocation operation is initiated, loading all records of the raw data block sequence. Following the descending order of the physical transmission channel priority list, a round-robin allocation mechanism is executed, starting with the highest priority physical transmission channel and sequentially selecting raw data blocks from the sequence, allocating one raw data block per physical transmission channel at a time. After allocating to the lowest priority physical transmission channel, the allocation returns to the highest priority physical transmission channel, forming a closed-loop round-robin process. After all raw data blocks have been allocated, each physical transmission channel receives a set of raw data blocks proportional to its priority.

[0104] Perform a network codec check packet generation operation. For each set of raw data blocks allocated to a physical transmission channel, apply the Reed-Solomon coding algorithm to generate check data blocks. Encapsulate the raw data blocks and check data blocks in a fixed ratio into a network codec check packet entity, append a physical transmission channel number field and a data block index field, and output the network codec check packet.

[0105] The link transmission module broadcasts network encoding verification packets to the relay satellite via the inter-satellite Ka link. The relay satellite reconstructs the data according to the network encoding rules, and decodes and verifies the CRC of the reconstructed data.

[0106] Query nearby satellites, obtain link margin, and select relay satellites based on the link margin;

[0107] Furthermore, the neighbor discovery function of the onboard routing protocol stack is activated, and link status request signaling is broadcast periodically. Link status announcement messages from neighboring satellites are received, and the orbital parameter and device identifier fields in the messages are parsed to generate a dynamic neighbor satellite list. For each node in the dynamic neighbor satellite list, a two-way ranging operation is initiated, transmitting a ranging request pulse to the target satellite and recording the precise transmission timestamp; the ranging response pulse returned by the target satellite is received, and the precise reception timestamp is recorded. The timestamp data is processed according to the propagation delay calculation formula stored in the onboard equipment, and the spatial propagation loss value of the current link is output. The received signal strength indication value is measured synchronously, and the link margin index is calculated in combination with the spatial propagation loss value to generate a link quality assessment matrix. The row index of the link quality assessment matrix corresponds to the neighbor satellite node identifier, and the column index contains three entities: orbital altitude difference angle value, link margin index value, and carrier frequency offset value. The comparison and selection logic is executed, scanning all rows of the link quality assessment matrix, locating the row with the largest link margin index value, and extracting the neighbor satellite node identifier corresponding to that row as the relay satellite selection result.

[0108] Based on the optimized spectrum configuration and the modulation parameter configuration table, the broadcast frequency band is configured, and the transmission frequency is obtained.

[0109] Specifically, the process involves reading the sub-band number field, channel allocation strategy encoding field, and center frequency point physical coordinate field from each record; simultaneously loading the corresponding record from the modulation parameter configuration table, and extracting the modulation order digital segment associated with the sub-band number field. Based on the binary weight parsing result of the channel allocation strategy encoding field, the sub-band is bound to the physical transmission channel. When the highest weight bit of the encoding field is 1, it is bound to physical transmission channel one; when the second highest weight bit is 1, it is bound to physical transmission channel two; and subsequent bits are bound to physical transmission channels three and four respectively, forming a set of mapping relationships between physical transmission channels and sub-bands. The frequency configuration template, which is stored in the non-volatile memory of the onboard transmitter, is accessed. The frequency configuration template stores the correspondence between the modulation order digital segment, the center frequency offset field, and the bandwidth occupancy factor field. The center frequency offset field and the bandwidth occupancy factor field are extracted by matching the modulation order digital segment with the frequency configuration template. For each set of sub-bands bound to a physical transmission channel, a frequency band boundary determination operation is performed: the minimum physical coordinate of the sub-band center frequency is used as the starting boundary of the frequency band, and the maximum physical coordinate of the sub-band center frequency, superimposed with the bandwidth occupancy coefficient field, is used as the ending boundary of the frequency band. The final frequency band range is then generated by superimposing the center frequency offset field. Based on the starting and ending boundaries of the frequency bands, the center transmission frequency is calculated, and four sets of structured data entities are output: physical transmission channel one and its starting, ending, and center transmission frequencies; physical transmission channel two and its starting, ending, and center transmission frequencies; physical transmission channel three and its starting, ending, and center transmission frequencies; and physical transmission channel four and its starting, ending, and center transmission frequencies.

[0110] Based on the transmission frequency, the network code check packet is sent to the relay satellite using an inter-satellite Ka link;

[0111] Specifically, the system accesses the transmit frequency data entities stored in the onboard processor. These entities contain four sets of structured records: Physical transmission channel one and its frequency band start boundary, frequency band end boundary, and center transmit frequency; Physical transmission channel two and its frequency band start boundary, frequency band end boundary, and center transmit frequency; Physical transmission channel three and its frequency band start boundary, frequency band end boundary, and center transmit frequency; and Physical transmission channel four and its frequency band start boundary, frequency band end boundary, and center transmit frequency. The transmit frequency data entities are traversed sequentially according to the physical transmission channel number field. For each physical transmission channel, the carrier generation parameters of the upconverter are configured: the center transmit frequency field is written to the control register of the frequency synthesizer, the frequency band start boundary field is set to the lower sideband cutoff point, and the frequency band end boundary field is set to the upper sideband cutoff point, completing the RF front-end initialization. The network coded check packet modulation operation is initiated, loading the four sets of entities in the network coded check packet set: the check packet sequence associated with physical transmission channel one, the check packet sequence associated with physical transmission channel two, the check packet sequence associated with physical transmission channel three, and the check packet sequence associated with physical transmission channel four. For each set of check packet sequences, the network-coded check packet entities are extracted in index order and input into the baseband signal port of the quadrature amplitude modulator. The modulator generates a carrier signal based on the center transmit frequency field of the current physical transmission channel, performs IQ quadrature mixing, and upconverts the baseband signal to a Ka-band radio frequency signal. Inter-satellite Ka-link broadcast transmission is performed, activating the beamforming circuit of the Ka-band phased array antenna and aligning it with the relay satellite's orbital coordinates. For the radio frequency signal generated by each physical transmission channel, it is boosted to the rated radiated power by a power amplifier and fed into the antenna radiating element array. The antenna control unit periodically transmits radio frequency signal pulse sequences according to the Space Data System Protocol (SDS) standard. The network-coded check packet entities are encoded as phase-modulated waveforms of the pulse sequences and propagated through free space to the relay satellite receiver. The bit error rate is monitored in real time throughout the transmission process. If no acknowledgment signal is received for three consecutive pulse sequences, an automatic retransmission mechanism is triggered to retransmit the current check packet sequence.

[0112] The relay satellite receives the network coded verification packet, reconstructs the data block sequence using the continuous phase detection algorithm, recovers lost data blocks, and generates a complete data block group.

[0113] Furthermore, the relay satellite activates its Ka-band receiver array to capture the radio frequency signal pulse sequence from the transmitting satellite. After down-converting the received radio frequency signal pulse sequence to baseband, it is input into the Viterbi soft-decision demodulator processing unit. The Viterbi soft-decision demodulator processing unit executes a continuous phase detection algorithm, reconstructs the modulation symbol sequence using a trellis graph path metric, and generates a bitstream of the original data block sequence and parity data blocks. Data recovery is initiated, and the error correction matrix of the Reed-Solomon decoder is loaded. The index number field and physical transmission channel number field in the bitstream are parsed, and the data block sequence is reassembled in ascending order of index number. When a discontinuous index number is detected, the parity data block activation mechanism is triggered: the associated parity data block is extracted, and finite field arithmetic operations are applied to reconstruct the content of the lost data block. After all index numbers are arranged consecutively, a complete data block group consisting of the original data blocks and the recovered data blocks is output.

[0114] Based on the complete data block group, calculate the CRC-16 value of the data block and generate the verification status code;

[0115] Furthermore, the three key elements of the complete data block group record are extracted: the index number field, the protocol metadata field, and the data unit field. The data unit fields are arranged in ascending order by index number, and a byte array concatenation operation is performed to generate a continuous data stream bit sequence. The initialization function of the cyclic redundancy check (CRC) calculation unit is activated, the initial value of the 16-bit register is set to all one, and the generator polynomial defined by the ISO 3309 standard is selected. The shift register bit operation procedure is initiated, with the data stream bit sequence shifted into the register bit by bit, starting from the most significant bit: when the most significant bit of the register is in a logical one state, an XOR operation of the generator polynomial is performed and the register is shifted left by one bit; when the most significant bit of the register is in a logical zero state, a left shift operation is directly performed. After all bits have been input, the 16-bit state value of the register is taken as the CRC-16 calculation result of the current complete data block group.

[0116] In summary, this invention achieves accurate identification of safe frequency bands in complex electromagnetic environments by: constructing a spectrum map with interference markers from Ka-band signal amplitude and phase data, and using a convolutional neural network to intelligently identify spectral interference states; furthermore, by combining a Q-learning algorithm to dynamically optimize the allocation of sub-band resources, improving the resource scheduling capability and transmission efficiency of inter-satellite communication systems under conditions of multiple interferences and time-varying channels. These two core steps respectively solve the problems of spectral response lag and rigid resource allocation in existing technologies, improving the spectrum utilization, communication reliability, and overall performance of spaceborne Ka-band data transmission systems in dynamic environments.

[0117] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A spaceborne four-channel Ka-band data transmission channel system, characterized in that: include, The spectrum sensing module collects raw spectrum data of frequency points within the Ka band, synchronously receives the interference hotspot database, constructs the raw spectrum matrix, marks the interference areas, and generates a spectrum map with interference markings. The spectrum optimization module inputs the spectrum map with interference markers into a pre-trained convolutional neural network, outputs the interference probability, identifies safe frequency bands, divides the safe frequency bands into micro sub-bands, optimizes the allocation scheme through the Q-learning algorithm, and generates an optimized spectrum configuration table. The dynamic modulation module dynamically adjusts the modulation mode according to the bandwidth parameters in the optimized spectrum configuration table, and divides the high-speed AOS data into blocks by frame, and generates network coding check packets in combination with the channel allocation strategy in the optimized spectrum configuration table. The link transmission module broadcasts network encoding verification packets to the relay satellite via the inter-satellite Ka link. The relay satellite reconstructs the data according to the network encoding rules, and decodes and verifies the CRC of the reconstructed data.

2. The spaceborne four-channel Ka-band data transmission channel system as described in claim 1, characterized in that: The raw spectrum data includes signal amplitude and signal phase.

3. The spaceborne four-channel Ka-band data transmission channel system as described in claim 2, characterized in that: The specific steps for constructing the original spectrum matrix, marking interference regions, and generating a spectrum map with interference markers are as follows: Construct the original spectrum matrix based on the signal amplitude and signal phase; Based on the interference hotspot database, interference is marked in the original spectrum matrix through dual judgment to generate interference mark vectors; The dual judgment refers to marking an interference when the amplitude value is greater than -90 dB / mW, and marking an interference when the frequency falls into any region of the interference hot zone database, thereby generating an interference mark vector. The original spectrum matrix is ​​fused with the interference marker vector to generate a spectrum map with interference markers.

4. The spaceborne four-channel Ka-band data transmission channel system as described in claim 3, characterized in that: The process of inputting the interference-tagged spectrum map into a pre-trained convolutional neural network, outputting the interference probability for each frequency band, and identifying safe frequency bands involves the following steps: Spectral feature data is extracted from the spectrum map with interference markers, and the spectrum feature data is standardized to generate a standardized feature matrix. Collect historical spectrum maps with interference markers and use them to train a convolutional neural network; The standardized feature matrix is ​​input into the trained convolutional neural network to generate interference probabilities; A safety threshold is set based on historical interference probabilities. When the interference probability is less than or equal to the safety threshold, the frequency band is determined to be safe.

5. The spaceborne four-channel Ka-band data transmission channel system as described in claim 4, characterized in that: The specific steps for dividing the secure frequency band into sub-bands are as follows. The highest modulation order is collected, the minimum bandwidth is calculated, and the subband width is obtained. Further, the highest supported modulation order is read from the onboard modem, and the minimum bandwidth required to meet the highest modulation order is calculated. The expression is: ； in, For minimum bandwidth, The system's nominal bit rate, The roll-off factor, The modulation order; Based on the minimum bandwidth required to meet the highest-order modulation requirement, the sub-band width is set to an integer multiple of the minimum bandwidth; The safe frequency band is divided into subbands based on the total width of the safe frequency band and the width of the subband.

6. The spaceborne four-channel Ka-band data transmission channel system as described in claim 5, characterized in that: The process of optimizing the allocation scheme using the Q-learning algorithm to generate an optimized spectrum allocation table involves the following steps: Measure the signal-to-noise ratio, interference power, and channel coherence bandwidth at the center frequency of the sub-band, and generate a sub-band state parameter table; Based on the subband state parameter table, an initial Q-learning table is constructed, and the policy optimization iteration is performed through the Q-learning algorithm to generate an optimized spectrum configuration table.

7. The spaceborne four-channel Ka-band data transmission channel system as described in claim 6, characterized in that: The specific steps for dynamically adjusting the modulation scheme based on the bandwidth parameters in the optimized spectrum configuration table are as follows: The bandwidth parameters of the sub-bands are extracted from the optimized spectrum configuration table, and a mapping rule between the bandwidth parameters and the modulation order is constructed. Based on the mapping rules, the modulation scheme is assigned to the sub-band, and a modulation parameter configuration table is generated.

8. The spaceborne four-channel Ka-band data transmission channel system as described in claim 7, characterized in that: The specific steps for dividing high-speed AOS data into frames and generating network coding verification packets by combining the channel allocation strategy in the optimized spectrum configuration table are as follows: Acquire high-speed AOS data streams and divide them into coded units to generate raw data block sequences; Extract channel priorities from the optimized spectrum configuration table, allocate raw data blocks from the raw data block sequence according to channel priorities, and generate network coding check packets.

9. The spaceborne four-channel Ka-band data transmission channel system as described in claim 8, characterized in that: The specific steps for broadcasting network-encoded verification packets to relay satellites via inter-satellite Ka links are as follows: query neighboring satellites, obtain link margin, and select relay satellites based on the link margin; Based on the optimized spectrum configuration table and the modulation parameter configuration table, configure the broadcast frequency band and obtain the transmission frequency; Based on the transmission frequency, network code check packets are sent to relay satellites using inter-satellite Ka links.

10. The spaceborne four-channel Ka-band data transmission channel system as described in claim 9, characterized in that: The relay satellite reconstructs the data according to network coding rules, decodes the reconstructed data, and verifies the CRC. The specific steps are as follows: The relay satellite receives the network coded verification packet, reconstructs the data block sequence using the continuous phase detection algorithm, recovers lost data blocks, and generates a complete data block group. Based on the complete data block group, calculate the CRC-16 value of the data block and generate the verification status code.

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