An unmanned aerial vehicle swarm channel degradation resistance communication method and system based on dynamic block cooperative transmission

Abstract

This invention discloses a UAV swarm communication method and system for resisting channel degradation based on dynamic block-based cooperative transmission, belonging to the field of wireless communication and UAV swarm communication technology. It constructs a network consisting of a ground control station, a cluster head, and multiple UAVs, monitors link status, and selects cooperative nodes under threshold triggering. The network is block-based according to channel capabilities and uses precoding and fountain code concatenation encoding. Strategies and synchronization are issued in the control time slot, while random access and parallel transmission occur in the data time slot. The ground control station receives data out of order and iteratively decodes it, adjusting redundancy and access parameters in a closed loop based on statistical results. This scheme maintains stable transmission under channel degradation and topology change scenarios and is suitable for tasks such as swarm video and radar backhaul.

Description

Technical Field

[0001] This invention belongs to the field of wireless communication and UAV swarm communication technology, and in particular relates to a UAV swarm anti-channel degradation communication method and system based on dynamic block cooperative transmission. Background Technology

[0002] Drone swarms transmit video, radar, and telemetry data over long distances in scenarios with strong interference and frequent maneuvers. Communication links fluctuate due to multipath fading, obstruction, node energy changes, and topology reconstruction. Traditional methods often rely on fixed routes or strong error correction on single links, making it difficult to balance high throughput and robustness. Centralized scheduling can unify resources, but it incurs high control plane overhead and is highly dependent on time synchronization and link stability. Fountain-type coding can mitigate packet loss, but without cross-layer adaptation and time slot organization, its efficiency can easily decrease under high concurrency and out-of-order reception. Therefore, a swarm communication scheme that balances control overhead, link fluctuations, and parallel carrying capacity is urgently needed. Summary of the Invention

[0003] In view of this, the present invention aims to propose a UAV swarm anti-channel degradation communication method and system based on dynamic block cooperative transmission, so as to at least solve one of the problems in the background art.

[0004] To achieve the above objectives, the technical solution of the present invention is implemented as follows:

[0005] A UAV swarm anti-channel degradation communication method based on dynamic block-based cooperative transmission includes the following steps:

[0006] Construct a communication network consisting of ground control stations, cluster head nodes, and multiple UAV nodes; define direct links and cooperative links; and set a frame structure consisting of control time slots, data time slots, and guard intervals, as well as a unified time reference.

[0007] Based on preset link status parameters, each link is periodically monitored, and transmission quality indicators are calculated. When the indicators are lower than the threshold, a set of cooperative nodes is selected to establish parallel sub-links.

[0008] Under the frame structure, the data to be transmitted is adaptively divided into blocks, and precoding and fountain code concatenation coding are performed to generate coded sub-blocks that can be received out of order;

[0009] In the control time slot, the cluster head issues the block strategy, coding parameters and substream mapping and completes time synchronization. In the data time slot, the cooperative node sends the coded sub-blocks in parallel in a random access manner. The ground control station performs unordered reception and iterative decoding. If the decoding threshold is not met, the missing sub-block is retransmitted.

[0010] Based on the frame cycle, the redundancy and access parameters are adjusted jointly by monitoring and decoding statistics, and the set of collaborative nodes is updated.

[0011] Furthermore, the link status parameters include signal-to-noise ratio, packet loss rate, and node remaining energy. The transmission quality indicators are weighted combinations of the above parameters and smoothed by a time window before being used for threshold comparison and mode triggering.

[0012] Furthermore, the set of collaborative nodes is selected by the cluster head according to the transmission quality indicators, and a backup node is used to replace the node when the signal-to-noise ratio decreases, the packet loss rate increases, or the remaining energy is lower than the threshold. When the cluster head fails, a new cluster head is generated through dynamic election by the bee colony to maintain topological continuity.

[0013] Furthermore, the concatenated coding adopts a combination of precoding and fountain coding. The precoding performs a linear transformation on the original symbols to obtain intermediate symbols. The fountain coding stage performs rateless coding based on the degree distribution to form coded symbols containing redundancy. The coding parameters include at least the degree distribution and the target redundancy degree.

[0014] Furthermore, the control time slot is divided into a cluster head broadcast area and a UAV feedback area. The cluster head sends out precoding parameters, substream allocation and synchronization signals, while the UAV reports its remaining energy, position and signal quality.

[0015] Furthermore, the data time slot employs a carrier sense and collision avoidance mechanism. When a collision occurs, binary exponential backoff is performed and is subject to a maximum retry limit. The ground control station sends back a reception confirmation at the end of the data time slot.

[0016] Furthermore, the iterative decoding adopts a sparse graph-based belief propagation algorithm, which prioritizes the processing of encoded symbols with a degree of one to gradually recover intermediate symbols. When the decoding threshold is reached, the original data is reconstructed; if the threshold is not reached, a missing sub-block retransmission request is generated.

[0017] Furthermore, cross-layer joint adjustments are made to read the decoding success rate, number of collisions, and idle listening time on a frame-by-frame basis, and to update the coding redundancy and contention window in a coordinated manner, and to select a modulation and channel coding scheme that matches the current channel conditions.

[0018] Furthermore, this solution discloses a communication system for implementing a UAV swarm anti-channel degradation communication method based on dynamic block cooperative transmission, including a ground control station, a cluster head node, and multiple UAV nodes. The ground control station is equipped with a receiving and iterative decoding module and a statistics and retransmission control module. The cluster head node is equipped with a link monitoring and mode triggering module, a cooperative node selection and scheduling module, a block and precoding module, and a control signaling and substream mapping module. Each UAV node is equipped with a fountain coding and random access transmission module and a status reporting module. The system completes the timing organization of control and data through the frame structure.

[0019] Furthermore, this solution discloses a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the aforementioned UAV swarm anti-channel degradation communication method based on dynamic block cooperative transmission.

[0020] Compared with existing technologies, the UAV swarm anti-channel degradation communication method and system based on dynamic block cooperative transmission described in this invention has the following advantages:

[0021] (1) The UAV swarm anti-channel degradation communication method and system based on dynamic block cooperative transmission described in this invention separates the control time slots and data time slots under a unified time reference. The control information and service data do not interfere with each other, the timing is more stable, and it is convenient to maintain continuous communication when the UAV moves and the topology changes;

[0022] (2) The UAV swarm anti-channel degradation communication method and system based on dynamic block cooperative transmission described in this invention is that the data is divided according to the current link capacity and an appropriate amount of redundancy is added. The ground end can complete the recovery when the sub-blocks arrive out of order or there is packet loss, thereby reducing the number of repeated transmissions and improving the available throughput under weak channels.

[0023] (3) The UAV swarm anti-channel degradation communication method and system based on dynamic block cooperative transmission described in this invention, based on the cooperative node selection and replacement mechanism of link status (signal-to-noise ratio, packet loss rate, remaining power), ensures that the number of parallel transmission nodes is always kept at an appropriate scale. When a node's link deteriorates or its power is insufficient, it quickly switches to a replacement node, while trying to maintain the existing sub-stream mapping and transmission rhythm as much as possible, reducing data plane jitter;

[0024] (4) The UAV swarm anti-channel degradation communication method and system based on dynamic block cooperative transmission described in this invention adopts random access and unified confirmation for data time slots. Before the cooperative nodes transmit in parallel, they listen to the channel and back off according to the rules if a conflict occurs; the ground control station uniformly feeds back the reception results at the end of the time slot, and clarifies the sub-blocks that need to be retransmitted, thereby reducing invalid contention and unnecessary retransmission. Attached Figure Description

[0025] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0026] Figure 1 This is a schematic diagram of a UAV swarm anti-channel degradation communication method based on dynamic block cooperative transmission, as described in an embodiment of the present invention. Detailed Implementation

[0027] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0028] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0029] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0030] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0031] To address the communication challenges of UAV swarms in complex electromagnetic environments, this invention proposes a channel-degrade-resistant communication method and system based on dynamic block-based cooperative transmission, enabling intelligent decomposition and cooperative recovery of high-speed information streams among distributed nodes. The system employs a hybrid multiple access scheme of TDMA control time slots and CSMA data time slots. The communication frame structure is divided into dedicated control time slots and contention-based data time slots: the control time slots, based on the TDMA mechanism, are synchronously distributed to each UAV node via fixed time slots by the cluster head, using key information such as the block strategy, precoding parameters, and substream allocation scheme generated by the dynamic block engine; the data time slots use the CSMA / CA protocol, performing secondary processing such as adding LT code redundancy and adapting modulation parameters on the received substreams before parallel transmission to the ground control station via an adaptive backoff algorithm; the ground control station's cooperative recovery module completes iterative decoding and information reconstruction, significantly enhancing the anti-interference communication capability and cooperative combat effectiveness of UAV swarms in complex electromagnetic environments. The specific scheme is as follows:

[0032] This embodiment deploys a communication network consisting of a ground control station, cluster head nodes, and multiple UAV nodes under a unified time reference. The network simultaneously supports direct communication from the ground station to UAVs and collaborative communication between UAVs. The system divides communication frames into control time slots, data time slots, and guard intervals, using a time-series organization that separates control and data to carry centralized block transmission and distributed transmission. During operation, the cluster head and ground control station periodically monitor link status and calculate transmission quality indicators. When these indicators fall below a threshold, dynamic block collaborative transmission is initiated, and a set of collaborative nodes is selected to carry parallel sub-links. The cluster head issues block strategies, encoding parameters, and sub-stream mappings in the control time slot and completes time alignment. Each collaborative node sends encoded sub-blocks in parallel using random access in the data time slot. The ground control station buffers arriving encoded symbols in an out-of-order reception mode. After meeting the decoding threshold, iterative decoding and reconstruction of the original data are performed. If decoding is insufficient, a retransmission request for missing sub-blocks is generated. The system periodically analyzes link and decoding information and adjusts redundancy and access parameters accordingly, ensuring the above process operates in a closed loop and converges to a stable state within the set frame structure.

[0033] Link state parameters include signal-to-noise ratio, packet loss rate, and node remaining energy. The system collects and normalizes these parameters using a sliding time window to form a single transmission quality index, which is used for mode triggering and node reselection. To suppress transient jitter, this embodiment performs time smoothing on the above indicators before comparing them with thresholds, thereby avoiding frequent switching caused by short-term interference.

[0034] The set of cooperating nodes is sorted and selected by the cluster head based on transmission quality indicators, and a replacement target is set for each active node. When the signal-to-noise ratio of a cooperating node decreases, the packet loss rate increases, or the remaining energy is insufficient to reach a preset level, the system performs seamless replacement without changing the intra-frame timing organization, and tries to use the existing sub-stream mapping to reduce data plane jitter. If the cluster head fails or loses connection, the swarm quickly elects a new cluster head to take over the scheduling and issue control commands through dynamic election to ensure topology continuity.

[0035] Dynamic segmentation and coding employ a concatenated scheme of precoding and fountain codes. The cluster head adaptively segments the original data stream based on channel capacity and target redundancy. During the precoding stage, intermediate substreams are output to reduce subsequent decoding complexity and enhance anti-deletion capabilities. In the fountain code stage, coded symbols with redundancy attributes are generated based on a predetermined degree distribution, facilitating joint recovery by the receiver under out-of-order conditions. The coding parameters include at least the degree distribution and target redundancy, both of which are sent along with the segmentation strategy in the control time slot.

[0036] The control time slots employ a fixed timing sequence using time-division multiple access, with broadcasting preceding feedback. The cluster head broadcasts precoded parameters, substream allocation schemes, and synchronization information to the target UAV, and can annotate scheduling instructions according to task priority. The UAV reports remaining energy, real-time location, signal quality, and mission progress in the feedback area, which is used by the cluster head and ground control station for subsequent node maintenance and parameter adjustments.

[0037] The data time slot employs a random access mechanism combining carrier sense and collision avoidance. Coordinating nodes transmit immediately upon detecting idle time, implementing exponential backoff for collisions and subject to a maximum retry limit. Ground control stations provide unified feedback confirmation at the end of the data time slot. To reduce congestion and idle time sensing overhead, the system smoothly adjusts the contention window based on historical load, while combining energy detection and preamble identification for occupancy determination, thereby maintaining predictable access efficiency under high concurrency conditions.

[0038] The ground control station buffers and filters coded symbols under out-of-order reception conditions. When the decoding threshold is reached, an iterative algorithm based on sparse graphs is used to gradually recover intermediate symbols, and then the original data is reconstructed through the reverse process of precoding. If the threshold is not reached, a retransmission list of missing sub-blocks is generated based on coverage and network load, and published in the next control time slot to drive subsequent parallel completion.

[0039] Cross-layer joint adjustment is performed on a frame-by-frame basis. The system statistically analyzes metrics such as decoding success rate, collision count, and idle listening time, and updates coding redundancy and contention window accordingly. When necessary, it selects a physical layer modulation and channel coding combination that better matches the current channel conditions. This process is performed without changing the intra-frame timing ratio, shortening the time from environmental changes to system convergence and improving overall transmission stability.

[0040] The frame structure includes control time slots, data time slots, and guard intervals. The typical frame period is set to ten milliseconds, but can be adjusted within the range of five to twenty milliseconds depending on the task and electromagnetic environment. Control and data maintain a fixed ratio and order within each frame to reduce mutual interference between control signaling and data transmission and ensure consistent behavior across frames.

[0041] Furthermore, the system disclosed in this scheme consists of a ground control station, cluster head nodes, and multiple UAV nodes. The ground control station is equipped with a receiving and iterative decoding module, as well as a statistics and retransmission control module, for handling out-of-order reception, decoding, and retransmission organization. The cluster head nodes are equipped with a link monitoring and mode triggering module, a cooperative node selection and scheduling module, a block partitioning and precoding module, and a control signaling and substream mapping module, for completing centralized policy generation and control broadcasting within time slots. The UAV nodes are equipped with a fountain coding and random access transmission module and a status reporting module, for handling end-side coding, carrier sense access, and status reporting. These three types of nodes complete the timing organization and coordinated operation of control and data under the frame structure described.

[0042] In high-volume backhaul tasks such as video and radar transmission, this embodiment significantly reduces control overhead and maintains high end-to-end throughput and recovery probability under conditions of node replacement and link fluctuations by combining centralized block partitioning with random access at the edge. It is suitable for swarm mission scenarios involving long distances, strong interference, and frequent topology changes. Simulation comparisons show that this solution has significant advantages in key indicators such as throughput, fault tolerance, and latency under conditions of high packet loss rate and node failure.

[0043] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for anti-channel-degradation communication of a UAV swarm based on dynamic block cooperative transmission, characterized in that: The method comprises the following steps: A communication network composed of a ground control station, a cluster head node and multiple unmanned aerial vehicle nodes is constructed, a direct link and a cooperative link are defined, and a frame structure composed of a control time slot, a data time slot and a guard interval and a unified time reference are set; Periodic monitoring of each link is performed based on preset link state parameters, a transmission quality index is calculated, and when the transmission quality index is lower than a threshold, a cooperative node set is selected to establish a parallel sub-link; Under the frame structure, the to-be-transmitted data is adaptively blocked, pre-coding and fountain code cascade coding are performed to generate coded sub-blocks that can be received out of order; In the control time slot, the cluster head issues a blocking strategy, coding parameters and sub-flow mapping and completes time synchronization, in the data time slot, the cooperative nodes send the coded sub-blocks in parallel in a random access manner, the ground control station performs out-of-order reception and iterative decoding, and when a decoding threshold is not met, missing sub-block retransmission is triggered; According to the frame period, the redundancy and access parameters are jointly adjusted and the cooperative node set is updated according to the monitoring and decoding statistics; The cascade coding adopts a combination of pre-coding and fountain code, pre-coding performs linear transformation on the original symbols to obtain intermediate symbols, and in the fountain code stage, no-rate coding is performed based on a degree distribution to form coded symbols containing redundancy, and the coding parameters at least include the degree distribution and the target redundancy degree; Iterative decoding adopts a belief propagation algorithm based on a sparse graph, and the coded symbols with a degree of one are preferentially processed to gradually recover the intermediate symbols, and when a decoding threshold is reached, the original data is reconstructed, and when the threshold is not reached, a missing sub-block retransmission request is generated. 2.The UAV swarm anti-channel-degradation communication method based on dynamic block cooperative transmission according to claim 1, characterized in that: The link state parameters include a signal-to-noise ratio, a packet loss rate and a node residual energy, and the transmission quality index is obtained by weighted combination of the above parameters and is smoothed by a time window and is used for threshold comparison and mode triggering. 3.The method of claim 1, wherein: The cooperative node set is selected by the cluster head according to the transmission quality index, and when the node signal-to-noise ratio decreases, the packet loss rate increases or the residual energy is lower than a threshold, a backup node is replaced, and when the cluster head fails, a new cluster head is generated through a bee swarm dynamic election to maintain topological continuity. 4.The method of claim 1, wherein: The control time slot is divided into a cluster head broadcast area and an unmanned aerial vehicle feedback area, the cluster head issues pre-coding parameters, sub-flow allocation and a synchronization signal, and the unmanned aerial vehicle reports residual energy, position and signal quality.

5. The method of claim 1, wherein: The data time slot adopts a carrier sensing and collision avoidance mechanism, when a collision occurs, a binary exponential backoff is performed and is limited by a maximum retry number, and the ground control station feeds back a reception confirmation at the end of the data time slot. 6.The method of claim 1, wherein: Cross-layer joint adjustment reads the decoding success rate, the number of collisions and the idle sensing time at a frame period, and updates the coding redundancy and the contention window in linkage, and selects a modulation and channel coding mode matched with the current channel condition.

7. A communication system for implementing the method of claim 1, characterized by The system comprises a ground control station, a cluster head node and multiple unmanned aerial vehicle nodes, the ground control station is configured with a reception and iterative decoding module, a statistics and retransmission control module, the cluster head node is configured with a link monitoring and mode triggering module, a cooperative node selection and scheduling module, a blocking and pre-coding module and a control signaling and sub-flow mapping module, each unmanned aerial vehicle node is configured with a fountain coding and random access sending module and a state reporting module, and the system completes the timing organization of control and data through the frame structure.

8. A computer readable storage medium storing a computer program, characterized in that: The computer program is executed by a processor to implement the unmanned aerial vehicle swarm channel degradation resistance communication method based on dynamic block cooperative transmission according to any one of claims 1-6.

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