A pilot conflict optimization allocation method based on a graph coloring mechanism

Abstract

This invention relates to the field of pilot conflict optimization and allocation technology, specifically to a pilot conflict optimization and allocation method based on a graph coloring mechanism. The method includes: acquiring a set of terminals to be allocated, a set of sensing tasks, and a set of pilot resources; identifying non-reusable relationships and pilot reuse-limited relationships to form a conflict constraint graph where nodes are terminals to be allocated and edges are pilot conflict constraints, resulting in a conflict graph to be colored; obtaining an initial coloring result based on conflict priority and conflict type identifiers; outputting a pilot color mapping table and a pilot allocation scheme; issuing pilot configurations to the corresponding terminals; locally updating the pilot conflict constraint graph; performing repair coloring only on affected subgraphs; and outputting the pilot allocation scheme. This feedback-driven local update mechanism enables pilot allocation to quickly and adaptively adjust according to network state changes, ensuring timely conflict resolution, reducing system reconfiguration costs, and improving stability and continuity.

Description

Technical Field

[0001] This invention relates to the field of pilot conflict optimization allocation technology, and in particular to a pilot conflict optimization allocation method based on graph coloring mechanism. Background Technology

[0002] With the development of integrated sensing and communication networks, communication and sensing functions operate collaboratively on the same spectrum and hardware platform. Pilot resources are not only used for communication channel estimation but also for sensing signal processing and environmental detection. In this context, the pilot resource allocation mechanism directly affects communication link quality, sensing accuracy, and overall system stability, becoming a critical fundamental issue in sensing and communication networks.

[0003] Existing pilot allocation methods are mostly designed for traditional cellular communication systems, primarily employing fixed allocation, random allocation, or simple multiplexing strategies based on distance and interference. These methods focus solely on interference suppression between communication links, ensuring channel estimation accuracy by constraining the pilot multiplexing relationship between adjacent terminals. However, in integrated sensing scenarios, pilots have a strong coupling effect on communication and sensing performance, and pilot multiplexing can easily lead to problems such as sensing echo aliasing, target detection ambiguity, and degraded positioning accuracy. Existing methods do not model the spatial overlap characteristics and cooperative constraints between sensing tasks, making it difficult to achieve joint optimization of communication and sensing performance.

[0004] Furthermore, with increasing demands for network security, differences exist among different terminals in terms of access trustworthiness, location sensitivity, and access to core areas. Pilot reuse may introduce potential information leakage risks or interference amplification effects. Existing pilot allocation methods typically do not incorporate security risk factors into unified modeling, resulting in a lack of effective constraint mechanisms for pilot allocation in high-security scenarios. On the other hand, most existing methods employ static or periodic global optimization strategies, requiring the reallocation of pilots for all terminals when network conditions change, leading to high computational overhead and potential system oscillations. The lack of dynamic correction mechanisms based on actual operational feedback makes it difficult to promptly identify new conflict relationships caused by environmental changes, terminal movement, or task adjustments, resulting in insufficient adaptability and robustness of pilot allocation schemes. Summary of the Invention

[0005] This invention provides a pilot conflict optimization allocation method based on graph coloring mechanism. In a communication and sensing integrated network, it can comprehensively consider multiple factors such as communication interference, sensing coupling and security risks, construct a unified pilot conflict modeling method, and realize an efficient, controllable and dynamically adaptive pilot allocation mechanism on this basis.

[0006] A pilot collision optimization allocation method based on graph coloring mechanism includes the following steps: S1: Constructing a pilot conflict constraint graph: Obtain the set of terminals to be assigned, the set of sensing tasks, and the set of pilot resources in the target sensor network; based on the link interference relationship, sensing coupling relationship, and security risk relationship in the set of terminals to be assigned, identify the pilot non-reusability relationship and pilot limited reuse relationship between each terminal, and form a pilot conflict constraint graph with nodes as terminals to be assigned and edges as conflict constraints; generate a conflict priority identifier for each node in the pilot conflict constraint graph, and generate a conflict type identifier for each edge to obtain a conflict graph to be colored; S2: Perform layered graph coloring optimization allocation: Input the conflict graph to be colored into the graph coloring allocation engine. Based on the conflict priority identifier and conflict type identifier, first perform strong constraint coloring on the absolute conflict edges of the pilots, and then perform conditional coloring on the pilot limited reuse edges to obtain the initial coloring result. Subsequently, combined with the perception isolation requirements, security disturbance requirements and historical coloring continuity, perform color rearrangement, local color replacement and private pilot additional identifier generation on the initial coloring result, and output the pilot color mapping table and pilot allocation scheme. S3: Implement pilot distribution and conflict repair: Distribute pilot configurations to the corresponding terminals according to the pilot color mapping table and pilot allocation scheme, and collect training feedback, perception feedback and conflict verification feedback after pilot execution; Based on the training feedback, perception feedback and conflict verification feedback, identify failed coloring nodes and newly added conflict edges, locally update the pilot conflict constraint graph, and only perform repair coloring on the affected subgraphs, and output the updated pilot allocation scheme.

[0007] Optionally, S1 specifically includes: S11: Obtain the list of active terminals in the target sensor network from the network management module as the terminal set to be assigned, obtain the current sensing tasks to be executed and the sensing range and sensing accuracy requirements from the sensing task queue as the sensing task set, and obtain the currently idle pilot sequence codebook from the resource pool as the pilot resource set. S12: Based on the spatial distance between each pair of terminals in the set of terminals to be assigned, the beam pointing overlap, and the signal-to-interference-plus-noise ratio prediction at the receiving end, determine whether there is a link interference relationship; based on whether the sensing tasks associated with each pair of terminals have overlapping sensing coverage areas or collaborative sensing targets, determine whether there is a sensing coupling relationship; based on the trust level difference between each pair of terminals, the sensitivity of historical access locations, and whether there are scenarios of simultaneous access to the core security area, determine whether there is a security risk relationship. S13: If there is a link interference relationship or a high-risk relationship in the security risk relationship between the two terminals, it is determined that there is a pilot non-reusable relationship between the two, and an absolute conflict edge is constructed between the corresponding nodes in the graph; if there is a perception coupling relationship or a general concern relationship in the security risk relationship between the two terminals, it is determined that there is a pilot limited reuse relationship between the two that allows reuse under limited conditions, and a limited reuse edge is constructed between the corresponding nodes in the graph; thus forming a pilot conflict constraint graph with nodes as terminals to be allocated and edges as conflict constraints.

[0008] Optionally, determining whether a link interference relationship exists specifically includes: Acquire the spatial location information, communication beam pointing information, and current communication parameters of the two terminals to be assigned; calculate the spatial distance between the two terminals based on the spatial location information, and determine whether the spatial distance is less than the preset interference distance threshold; The communication beam pointing information is used to determine the coverage area of ​​the communication beams of the two terminals to be assigned, and it is determined whether there is spatial overlap in the coverage area of ​​the communication beams exceeding the preset overlap ratio threshold; the received signal-to-interference-plus-noise ratio between the two terminals to be assigned is predicted based on the communication parameters, and it is determined whether the predicted signal-to-interference-plus-noise ratio is lower than the preset signal-to-interference-plus-noise ratio threshold. When the spatial distance is less than the preset interference distance threshold, or the overlap ratio of the communication beam coverage area exceeds the preset overlap ratio threshold, or the predicted signal-to-interference-plus-noise ratio is lower than the preset signal-to-interference-plus-noise ratio threshold, it is determined that there is a link interference relationship between the two terminals to be allocated, and the corresponding terminal node pair is marked as a pilot conflict candidate relationship.

[0009] Optionally, S1 further includes: Based on the service priority, mobility speed, or channel time-varying characteristics of each terminal, a conflict priority identifier is generated for each node in the pilot conflict constraint graph; based on the interference intensity, coupling tightness, or risk level corresponding to each edge, a conflict type identifier is generated for each edge, resulting in a conflict graph to be colored.

[0010] Optionally, S2 specifically includes: S21: Input the conflict graph to be colored into the graph coloring assignment engine, traverse all edges in the graph with conflict type identifiers; prioritize the processing of connection relationships marked as absolute conflict edges, determine the coloring order according to the conflict priority identifier of each node, assign different pilot colors to adjacent nodes with absolute conflict edges, and ensure pilot orthogonality under strong constraints. S22: Based on the absolute conflict edge constraint, perform conditional coloring on the connection relationship marked as limited reuse edge; according to the perception coupling tightness or security concern level associated with the limited reuse edge, set the interference tolerance threshold, and determine whether the two end nodes can reuse the same pilot color under the premise of meeting the perception isolation requirements or security disturbance requirements; if the condition is met, reuse is allowed; otherwise, different colors are assigned, and the initial coloring result is generated. S23: Obtain the coverage area of ​​the sensing task in the current network topology as the sensing isolation requirement, obtain the terminal distribution density and security area distribution as the security disturbance requirement, and obtain the pilot color of each terminal in the previous scheduling cycle as a historical coloring continuity reference; based on the sensing isolation requirement, rearrange the spatial distribution of nodes of the same color in the initial coloring result to reduce sensing interference; based on the security disturbance requirement, locally change the color of the nodes around the high-risk area to improve anti-interception capability; based on the historical coloring continuity, perform inheritance adjustment on the color of the handover or re-access terminal; generate a private pilot additional identifier for the terminal carrying the sensing task or security sensitive service, indicating that a private pilot sequence is superimposed on the public pilot; finally output a pilot color mapping table including the correspondence between terminal identifier and pilot color, and a pilot allocation scheme including the specific pilot sequence allocation result.

[0011] Optionally, determining the coloring order based on the conflict priority identifier of each node includes reading all nodes in the conflict graph to be colored and obtaining the conflict priority identifier corresponding to each node; sorting all nodes according to the numerical value of the conflict priority identifier, arranging the nodes in descending order of the conflict priority identifier value; when there are nodes with the same conflict priority identifier value, performing a secondary sort according to the number of conflicting edges associated with the node or the node connectivity; after sorting, generating a node processing sequence as the node coloring order of the graph coloring allocation engine; the graph coloring allocation engine performing pilot color allocation on each node in sequence according to the node processing sequence, so that nodes with higher conflict priority identifier values ​​complete pilot coloring first, reducing the probability of conflict in the subsequent node coloring process.

[0012] Optionally, the step of setting an interference tolerance threshold and determining whether the two nodes can reuse the same pilot color under the premise of meeting the sensing isolation requirements or security disturbance requirements specifically includes: Based on the communication quality requirements of the target sensor network and the pilot channel estimation accuracy requirements, a minimum signal-to-interference-plus-noise ratio requirement is set as the basic signal quality threshold. Based on network type, terminal service type, and sensing task accuracy requirements, the basic signal quality threshold is graded and corrected to obtain a basic interference tolerance level that matches the service scenario. The basic interference tolerance level is dynamically adjusted based on the current network load level, terminal spatial distribution density, and interference environment intensity to generate the interference tolerance threshold for the current scheduling period. When performing pilot condition reuse determination, the predicted signal-to-interference-plus-noise ratio (SINR) between two terminals connected through a limited reuse edge is obtained, and the predicted SINR is compared with the interference tolerance threshold. When the predicted SINR is not lower than the interference tolerance threshold, the pilot reuse condition is determined to be met. When the predicted SINR is lower than the interference tolerance threshold, the pilot reuse condition is determined not to be met, thereby guiding the pilot color allocation decision.

[0013] Optionally, S3 specifically includes: S31: Based on the correspondence between terminal identifiers and pilot colors in the pilot color mapping table, select the corresponding pilot sequence from the pilot resource set and send the pilot configuration to the corresponding terminal through downlink control signaling; within the predetermined monitoring period after the pilot configuration is executed, collect the channel state information reported by each terminal as training feedback, collect the echo detection data of each sensing task node as sensing feedback, and monitor the uplink pilot received power and interference noise level as collision verification feedback; S32: Based on the training feedback analysis, analyze the channel estimation quality of each terminal. If the channel estimation error of a terminal exceeds a preset threshold, the corresponding terminal is determined to be a failed colored node due to interference. Based on the perception feedback analysis, analyze the detection signal-to-interference-plus-noise ratio or target detection probability of the perception task. If the pilot reuse of adjacent terminals causes the perception performance to degrade beyond the tolerance threshold, it is determined that there is a newly added perception coupling conflict edge between the two terminals. Based on the conflict verification feedback, detect whether there is a demodulation failure event caused by pilot collision. If periodic or continuous pilot interference occurs between a pair of terminals, it is determined that there is a newly added link interference conflict edge between them. According to the identified failed colored nodes and newly added conflict edges, add, delete, or change the type of the corresponding nodes and edges in the pilot conflict constraint graph to achieve local graph update. S33: Determine the scope affected by the local update, extract the subgraph including the failed colored nodes and their adjacent nodes, as well as the nodes associated with the newly added conflicting edges, as the affected subgraph; keep the pilot colors of other nodes outside the affected subgraph unchanged, and only perform repair coloring on the affected subgraph; during the repair coloring process, prioritize inheriting the colors that have not caused conflicts in the original color allocation, and perform local color adjustment on the unusable colors caused by failed nodes or newly added conflicting edges, so as to achieve pilot conflict resolution of all nodes in the subgraph with the minimum color adjustment cost; update the pilot color mapping table and pilot allocation scheme based on the repair coloring results, and output the updated pilot allocation scheme for use in the next scheduling cycle.

[0014] Optionally, determining the existence of a new perceptual coupling conflict edge between the two terminals specifically includes: The system acquires echo detection data and corresponding sensing result data of each node performing the sensing task after the pilot configuration takes effect, and evaluates the signal quality and target detection effect of each sensing task. For terminal combinations participating in pilot reuse, the system analyzes the changes in sensing performance before and after pilot reuse, and identifies whether there is a decrease in sensing signal quality or a deterioration in detection effect caused by pilot reuse. The system tracks and judges the changes in sensing performance over multiple consecutive observation periods. When the sensing signal quality is detected to be continuously lower than the preset requirements or the target detection effect is continuously decreased and exceeds the tolerance range, it is determined that there is a stable sensing interference relationship between the corresponding terminals. Based on the judgment result, a limited reuse conflict edge is added between the corresponding terminal nodes in the pilot conflict constraint graph to represent the newly added sensing coupling conflict relationship and to constrain the subsequent pilot allocation process.

[0015] Optionally, the step of resolving pilot conflicts for all nodes within the subgraph with minimal color adjustment cost specifically includes: Extract the affected subgraph based on the failed colored nodes and newly added conflict edges, and keep the original pilot colors of each node outside the affected subgraph unchanged; check the availability of the currently assigned pilot colors of each node in the affected subgraph one by one, and retain the original pilot colors when the original pilot colors still meet the updated conflict constraints. When the original pilot color does not meet the updated conflict constraints, the corresponding node is identified as a node to be adjusted. For each node to be adjusted, candidate colors that will not cause pilot conflicts with adjacent nodes are selected from the currently available pilot colors, and candidate colors that can keep the colors of adjacent stable nodes unchanged and will not cause new conflicts are selected as replacement colors. When multiple candidate colors meet the conflict resolution requirements, the candidate color that results in the fewest color change nodes and the smallest color transfer adjustment range is selected first. The pilot color redistribution of each node to be adjusted in the affected subgraph is completed in the above manner until all nodes in the affected subgraph meet the conflict constraint conditions, so as to achieve pilot conflict resolution of all nodes in the subgraph with the minimum color adjustment cost.

[0016] The beneficial effects of this invention are: This invention constructs a pilot conflict constraint graph, which maps link interference, sensing coupling, and security risk relationships into conflict edges in the graph structure. Furthermore, it distinguishes between two constraint types: absolute conflict and limited reuse conflict, achieving hierarchical modeling of pilot reuse relationships. Compared to traditional methods based solely on interference or distance, this solution simultaneously considers communication performance, sensing task requirements, and security constraints. Pilot allocation no longer relies on a single indicator but is based on comprehensive decision-making under multi-dimensional constraints, reducing the probability of pilot conflicts, improving pilot resource reuse efficiency, and enhancing the system's adaptability in complex integrated sensing scenarios.

[0017] This invention employs a layered graph coloring strategy during pilot allocation, prioritizing strong constraints and followed by conditional constraints. First, it strictly satisfies the orthogonal constraints of absolutely conflicting edges. Then, based on interference tolerance thresholds or sensing requirements, it conditionally determines the reuse limits for multiplexed edges, achieving controlled pilot reuse. Combining sensing isolation requirements, security disturbance requirements, and historical coloring continuity, it performs color rearrangement and local optimization on the initial coloring results, ensuring both communication reliability and sensing accuracy and security in the pilot allocation process. This mechanism overcomes the limitation of traditional graph coloring methods that only pursue the minimum number of colors, achieving a pilot allocation mode of controllable reuse and multi-objective optimization, thus improving the overall system performance.

[0018] This invention introduces training feedback, perception feedback, and conflict verification feedback to achieve real-time evaluation of pilot allocation effectiveness and dynamically identify failed nodes and new conflict relationships based on the feedback results. Furthermore, it performs local repair coloring only on affected subgraphs, prioritizing the retention of existing pilot allocations for non-conflicting nodes with the goal of minimizing color adjustment costs, thus avoiding the high overhead and system oscillations caused by global reconstruction. This feedback-driven local update mechanism enables pilot allocation to rapidly and adaptively adjust according to network state changes, ensuring timely conflict resolution, reducing system reconfiguration costs, and improving network stability and continuity. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only for this invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the method flow according to an embodiment of the present invention; Figure 2 This is a schematic diagram of layered color allocation according to an embodiment of the present invention. Detailed Implementation

[0021] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. For some well-known technologies, those skilled in the art may also use other alternative solutions to implement the invention. The accompanying drawings are only used to illustrate the embodiments in a more specific way and are not intended to limit the present invention.

[0022] like Figure 1 - Figure 2 As shown, a pilot conflict optimization allocation method based on graph coloring mechanism includes the following steps: S1: Constructing a pilot conflict constraint graph: Obtain the set of terminals to be assigned, the set of sensing tasks, and the set of pilot resources in the target sensor network; based on the link interference relationship, sensing coupling relationship, and security risk relationship in the set of terminals to be assigned, identify the pilot non-reusability relationship and pilot limited reuse relationship between each terminal, and form a pilot conflict constraint graph with nodes as terminals to be assigned and edges as conflict constraints; generate a conflict priority identifier for each node in the pilot conflict constraint graph, and generate a conflict type identifier for each edge to obtain a conflict graph to be colored; S1 specifically includes: S11, Topology and Task Awareness: Obtain the list of active terminals within the target adapted network from the network management module, and denote it as the set of terminals to be assigned: ; in, Indicates the first One terminal to be assigned. This indicates the number of terminals to be assigned.

[0023] Retrieve the set of perception tasks to be executed from the perception task queue: ; Each of the sensing tasks Including the range of perception With the requirement of perception accuracy .

[0024] Obtain the currently available pilot sequence codebook from the resource pool to form a pilot resource set: ; The S11 part of the scheme first uniformly acquires the terminals, sensing tasks, and available pilot resources in the network before performing pilot conflict modeling, providing basic data for subsequent conflict relationship identification and graph modeling. Specifically, this involves the network management module first reading the active terminal devices in the current sensor network and treating these terminals as objects requiring pilot allocation, forming a set of terminals to be allocated; then, reading the currently executing or about-to-be-executed sensing tasks from the sensing task queue in the system, with each sensing task including at least its corresponding spatial sensing range and required sensing accuracy, forming a set of sensing tasks; finally, obtaining the currently unoccupied pilot sequence codebook from the system's pilot resource pool, using these available pilot sequences as a set of pilot resources. Through the above process, the system simultaneously obtains three types of basic information: terminals to be allocated, sensing tasks, and available pilot resources, providing the necessary data foundation for subsequent analysis of interference relationships, sensing coupling relationships, and security risk relationships between terminals, and for constructing a pilot conflict constraint graph. Indicates the first One terminal to be assigned. This indicates the total number of terminals to be allocated. This indicates the number of perception tasks currently pending execution. Indicates the first A sensory task Representing the perception task Spatial perception coverage area. Representing the perception task The requirement for perception accuracy. Indicates the first pilot sequence, This indicates the number of pilot sequences currently available.

[0025] S12: Identification of Multidimensional Conflict Relationships S121, for any two terminals and ( ), calculate its spatial distance: ; in, Indicates terminal Spatial position vector, Indicates terminal Spatial position vector, It indicates the spatial distance between two terminals.

[0026] S122, Calculate the beam pointing overlap between the two terminals: ; in, Indicates terminal The communication beam coverage area Indicates terminal The communication beam coverage area Indicates the overlap ratio of the communication beams between the two terminals; S123, Predict the receiver's signal-to-interference-plus-noise ratio: ; in, Indicates terminal The transmission power, Indicates terminal To the terminal Channel gain, This indicates the interference power from other terminals. Indicates system noise power. Indicates system noise power. Indicates terminal Receive from terminal Predictive signal-to-interference ratio (SIR) for signals.

[0027] S124, if satisfied If so, it is determined that there is a link interference relationship between the two terminals.

[0028] in, This represents the interference distance threshold, used to determine whether pilot interference is likely to occur between two terminals in terms of spatial distance. Its value is 0.2 to 0.5 times the effective communication coverage radius of the network. In typical cellular or integrated sensor networks, this threshold is generally set in the range of 20 to 150; in macro coverage scenarios, it can be appropriately increased to 100 to 300. When the distance between two terminals is less than this threshold, a high probability of link interference is considered to exist. This represents the beam overlap threshold, which measures the degree of overlap in the spatial coverage areas of the communication beams of two terminals. Its value ranges from 0.2 to 0.6. When the overlap ratio of the coverage areas of the two terminals exceeds this threshold, it indicates that the communication energy of the two terminals has significant spatial overlap, which is prone to pilot interference. Therefore, it can be determined that there is a link interference relationship. It is usually taken as 0.3 to 0.5. The signal-to-interference-plus-noise ratio (SIR) threshold is used to measure the lower limit of communication quality at the receiver. When the predicted SIR is lower than this threshold, pilot multiplexing is considered to reduce the channel estimation quality. This threshold is set in the range of 0 to 10, and can be increased to 8 to 12 in high-reliability communication or high-precision sensing scenarios.

[0029] S125, Regarding the perception task coupling relationship, if the terminal With terminal The associated perceptual tasks are as follows: and Calculate the overlap of the sensing coverage area: ; in, Indicates task The sensing coverage area Indicates task The sensing coverage area This indicates the percentage overlap in the coverage areas of the two sensing tasks.

[0030] S126, if satisfied Then it is determined that there is a sensing coupling relationship between the two terminals.

[0031] in, This represents the threshold for perceived coverage overlap.

[0032] S127, Regarding security risk relationships, calculate the comprehensive security risk index between the two terminals: ; in, Indicates terminal With terminal Trust level coefficient, This represents the overall security risk index between the two terminals. This represents the sensitivity coefficient of historical access locations. This indicates the number of risk identifiers simultaneously accessing the core security zone. This represents the safety risk weighting coefficient. The value used to characterize the impact of differences in terminal trust levels on security risk assessment is usually between 0.3 and 0.6. When the system has high requirements for the trustworthiness of terminal identity, a larger weight can be used, such as 0.45 to 0.6. In ordinary access scenarios, it is usually between 0.35 and 0.5. This value is used to characterize the impact of a terminal's historical access location sensitivity on security risks, and its range is 0.2 to 0.4. In scenarios where network location security monitoring is strict, a value of 0.3 to 0.4 can be used; in conventional network environments, a value of 0.2 to 0.3 is typically used. This represents the potential risk associated with a terminal simultaneously accessing the core security zone, and its value ranges from 0.2 to 0.5. In core network areas or high-security zones, this weight is typically set to 0.35–0.5; or 0.2–0.35. In practical applications, to ensure the stability of the risk index, it is usually set to... The weighting, or a combination of weights close to 1, ensures that each risk factor remains interpretable and adjustable in the calculation of the comprehensive safety risk index.

[0033] S12 identifies whether there are interference, perceptual coupling, or security risk relationships between any two terminals, thus providing a basis for constructing pilot conflict constraint maps. The specific process can be understood as follows: The system first calculates the spatial distance between any two terminals, whether their communication beam coverage overlaps, and predicts the signal-to-interference-plus-noise ratio (SNR) at the receiver under the current network conditions. If the two terminals are too close, their communication beam coverages significantly overlap, or the predicted SNR is lower than a system-set threshold, then communication interference is considered possible between the two terminals, indicating a link interference relationship. The system then further determines whether the coverage areas of the perceptual tasks corresponding to the two terminals overlap. If the overlap ratio of the perceptual areas of the two tasks exceeds a set threshold, it indicates that the two terminals have a need for coordination or coupling at the perceptual level, indicating a perceptual coupling relationship. Finally, the system calculates a comprehensive security risk index based on factors such as differences in trust levels between terminals, the sensitivity of historical access locations, and whether they simultaneously access core security areas. If this risk index is high, a security risk relationship is considered to exist between the two terminals. Through the comprehensive identification of these three types of relationships, the system can comprehensively characterize the potential conflicts and correlations between terminals, providing a foundation for establishing subsequent pilot reuse constraints.

[0034] S13, Conflict Type Determination and Mapping: S131, let the pilot conflict constraint diagram be represented as follows: ; in, This represents the set of nodes, corresponding to the set of terminals to be assigned. This represents the set of conflict constraint edges between terminals.

[0035] S132, if there is link interference between the two terminals, or if the following conditions are met: ; If a pilot signal cannot be reused between the two terminals, an absolute conflict edge is constructed between the corresponding nodes in the graph. ; in, This represents a high-risk threshold, used to determine whether the overall security risk between two terminals reaches a level that necessitates prohibiting pilot reuse. Its value is typically determined based on the overall security risk index. The normalization range is set; because It is generally normalized to the range of 0 to 1, therefore The value ranges from 0.6 to 0.85. This represents the set of absolutely conflicting edges, that is, the set of all edges that have pilot non-reusable relationships. Indicates terminal node With terminal nodes A conflict constraint edge between them.

[0036] S133; If there is a sensing coupling relationship between the two terminals, or if the following conditions are met... If a pilot-limited multiplexing relationship exists between the two terminals under finite conditions, then a limited multiplexing edge is constructed between the corresponding nodes in the graph: ; in, This indicates the general level of concern risk threshold. This represents the set of limited reusable edges.

[0037] This results in a pilot conflict constraint graph where nodes are terminals to be assigned and edges are conflict constraints.

[0038] S14, Identifier generation: S141, for the nodes in the graph Calculate the conflict priority index: ; in, Indicates terminal The business priority coefficient ranges from 0 to 1, with a higher value indicating a higher business priority. This represents the terminal's moving speed, with a value ranging from 0 to 30. In low-speed IoT scenarios, it is typically 0 to 10. This represents the time-varying characteristic of the terminal channel, with a value ranging from 0 to 1, characterizing the degree to which the channel changes over time. This represents the node priority weight coefficient. The value ranges from 0.3 to 0.5. The value range is 0.2 to 0.4; The value ranges from 0.2 to 0.4. Or close to 1, to ensure that the weights of the conflict priority index are normalized; It represents the conflict priority index of the terminal node, with a theoretical value range of about 0 to 1.5. Under the weight normalization, it is usually distributed in the range of 0 to 1. according to The size is used to generate a conflict priority identifier for the node.

[0039] S142, for the edges in the graph Calculate the conflict intensity index: ; in, Indicates the interference strength between terminals. Indicates the tightness of the perceived coupling. Indicates the safety risk index. Represents the edge weight coefficient. This represents the overall conflict intensity index of the edges.

[0040] according to The size of each edge is used to generate a conflict type identifier, resulting in a colored conflict graph.

[0041] S2: Perform layered graph coloring optimization allocation: Input the conflict graph to be colored into the graph coloring allocation engine. Based on the conflict priority identifier and conflict type identifier, first perform strong constraint coloring on the absolute conflict edges of the pilots, and then perform conditional coloring on the pilot limited reuse edges to obtain the initial coloring result. Subsequently, combined with the perception isolation requirements, security disturbance requirements and historical coloring continuity, perform color rearrangement, local color replacement and private pilot additional identifier generation on the initial coloring result, and output the pilot color mapping table and pilot allocation scheme. S2 specifically includes: S21, Strongly Constrained Shading Stage: S211, the conflict map to be colored Input graph coloring assignment engine, where the node set is: ; Represents the set of terminals to be assigned and the set of edges: ; This indicates the conflict constraints between terminals.

[0042] S212, first traverse all edges in the graph that have conflict type labels, and then collect the set of edges labeled as absolutely conflicting: ; S213, prioritize processing based on the conflict priority index of each node. Sort the node set to form a coloring order sequence: ; in, This represents the node coloring order sequence, i.e., the order in which nodes are processed during the execution of the graph coloring algorithm. This represents a sorting function used to sort a set of nodes according to a specified index, i.e., determining the node processing order in the graph coloring algorithm. This prioritizes pilot allocation for terminals with high conflict risk or high stability requirements. Specifically, the process involves first reading all nodes in the conflict graph to be colored and obtaining the conflict priority index for each node. A larger conflict priority index indicates a higher terminal service priority, stronger mobility, or more significant channel changes, thus requiring priority for pilot allocation. Then, all nodes are sorted according to their conflict priority index values, from largest to smallest, with nodes having larger conflict priority indices appearing first. Nodes with smaller indices are placed at the back. After sorting, the system generates a node processing queue according to the sorted order. This queue is the node coloring order of the graph coloring algorithm. When performing pilot allocation, the graph coloring allocation engine processes each node in this order, prioritizing the selection of pilot colors that meet the conflict constraints for nodes at the front, and avoiding conflicting colors already assigned to preceding nodes when coloring subsequent nodes. Through the above sorting method, terminals with a large conflict impact or high business importance can be prioritized for pilot coloring, reducing the probability of conflicts during subsequent node allocation and improving the stability and feasibility of the overall pilot allocation.

[0043] S214, Perform pilot color assignment node by node according to the coloring order sequence. For any node... From the pilot resource set: Select the pilot color that satisfies the following constraints: ; This allows for the assignment of distinct pilot colors to adjacent nodes with absolutely conflicting edges, ensuring pilot orthogonality under strong constraints.

[0044] in, This represents the conflict graph to be colored. This represents the set of graph nodes, corresponding to the set of terminals to be assigned. This represents the set of conflicting edges in the graph; Represents the set of absolutely conflicting edges. Denotes the set of reusable edges. Indicates the first One terminal node, Indicates terminal node Conflict priority index Indicates the set of available pilot colors. Indicates assignment to the terminal pilot colors, Indicates the number of available pilot colors.

[0045] S22, Conditional Coloring Phase: Based on the coloring of absolutely conflicting edges, the set of edges marked as limited reusable edges is: ; Perform conditional coloring.

[0046] For any limited reuse edge Based on the conflict intensity index of the edges: ; in, Representing an edge The comprehensive conflict intensity index, Indicates the intensity of communication interference between terminals. Indicates the tightness of the perceived coupling. Indicates the safety risk index. This represents the conflict intensity weighting coefficient. Indicates the pilot reuse distance threshold. Indicates the interference tolerance threshold; After fulfilling the absolute conflict constraints, conditional coloring is applied to the connection relationships marked as limited-reuse edges. Based on the perceived coupling tightness or security concern level associated with the limited-reuse edges, the degree of pilot reuse constraint is determined, and an interference tolerance threshold is set. ; For any two terminal nodes connected by a limited multiplexing edge and Obtain the predicted signal-to-interference-plus-noise ratio between the two terminals. And determine whether the predicted signal-to-interference-plus-noise ratio meets the conditions. ; When the predicted signal-to-interference-plus-noise ratio is not lower than the interference tolerance threshold When the interference level between the two terminals is determined to be within the acceptable range of the system, the node is allowed to proceed. With nodes Reusing the same pilot color when the predicted signal-to-interference-plus-noise ratio is below the interference tolerance threshold When the interference level between two terminals exceeds the system's tolerance range, it is determined to be a node. With nodes Assign different pilot colors; after completing the conditional coloring judgment for all limited multiplexing edges, obtain the initial coloring result: ; in, Indicates terminal With terminal The predicted signal-to-interference-plus-noise ratio; This represents the set of initial pilot coloring results; Indicates terminal With pilot color The correspondence, This represents the system's permissible interference tolerance threshold. First, based on the current network's communication quality requirements and pilot estimation accuracy requirements, a minimum permissible signal quality level is pre-set; this level serves as the interference tolerance threshold. The interference tolerance threshold represents the minimum signal-to-interference-plus-noise ratio (SNR) requirement that the system can still guarantee channel estimation stability and communication reliability under pilot multiplexing conditions. Specifically, the basic SNR requirement is first determined based on network type, terminal service type, and sensing task accuracy requirements. For example, this is the minimum SNR level that ensures the channel estimation error is within an acceptable range. Then, this basic value is appropriately adjusted based on the current network load, terminal density, and interference environment to obtain the current scheduling... The system uses a periodic interference tolerance threshold. When performing conditional coloring, the system predicts the signal-to-interference-plus-noise ratio (SNR) of two terminals connected by a limited-reuse edge when multiplexing the same pilot, and compares this prediction with the interference tolerance threshold. If the predicted SNR is not lower than the interference tolerance threshold, it indicates that the communication and sensing functions can still be stably operated after pilot multiplexing, so the two terminals are allowed to reuse the same pilot color. If the predicted SNR is lower than the interference tolerance threshold, it is considered that the interference after multiplexing is too large, which will affect channel estimation or sensing performance, so different pilot colors are assigned to the two terminals. In this way, the reuse efficiency of pilot resources can be improved as much as possible while ensuring system performance.

[0047] S23, Optimization and Output Stage: Obtain the set of sensing tasks in the current network topology: ; And extract the coverage area of ​​each sensing task: ; As a requirement for sensory isolation; to obtain the spatial distribution density of terminals: ; And a collection of safe zones: ; As a safety disturbance requirement; simultaneously, the pilot color allocation results of the previous scheduling cycle are obtained. , represented as: ; as a reference for historical coloring continuity.

[0048] in, Indicates the terminal in the previous scheduling cycle Instead of assigning pilot colors The correspondence, Indicates that the previous scheduling period was for the terminal. The assigned pilot colors, This indicates the scheduling cycle number preceding the current scheduling cycle; Indicates the current pilot scheduling cycle number. This represents the set of pilot coloring results for the current scheduling period.

[0049] Based on the requirement of perceptual isolation, the initial coloring result The spatial distribution of nodes of the same color in the middle is re-colored to satisfy: To reduce mutual interference in perception.

[0050] Based on the security disturbance requirements, the set of nodes located near the boundary of the security zone is: ; Perform local staining to improve the randomness of pilot distribution.

[0051] Based on the continuity of historical coloring, color inheritance constraints are applied to terminal nodes: ; This reduces the training overhead caused by frequent switching.

[0052] Meanwhile, for the set of terminals carrying sensing tasks or security-sensitive services: ; Generate private pilot additional identifier: ; when When, it means that a private pilot sequence is superimposed on the public pilot sequence.

[0053] Final output pilot color map: ; And pilot allocation scheme: ; in, Represents a set of perception tasks. Indicates the area covered by the perception task. Indicates the spatial distribution density of terminals. Indicates network coverage area. Represents the set of safe zones. Indicates the first A safe zone, This represents the pilot coloring result of the previous scheduling cycle. Indicates the perceived isolation distance threshold. This represents the set of nodes near a high-risk area. Indicates the spatial location of the terminal. Indicates the extent of the safety zone boundary extension. Indicates additional markings for private pilot signals. This indicates the mapping relationship between the terminal and the pilot color. This indicates the final pilot allocation scheme.

[0054] S3: Implement pilot distribution and conflict repair: Distribute pilot configurations to the corresponding terminals according to the pilot color mapping table and pilot allocation scheme, and collect training feedback, perception feedback and conflict verification feedback after pilot execution; Based on the training feedback, perception feedback and conflict verification feedback, identify failed coloring nodes and newly added conflict edges, locally update the pilot conflict constraint graph, and only perform repair coloring on the affected subgraphs, and output the updated pilot allocation scheme.

[0055] S3 specifically includes: S31, Pilot configuration distribution and feedback acquisition: S311, based on the pilot color mapping table From pilot resource set The corresponding pilot sequence is selected and the pilot configuration is sent to the corresponding terminal through downlink control signaling.

[0056] S312, the predetermined monitoring period after pilot configuration execution. The following feedback information was collected: Obtain the channel status information reported by each terminal: As training feedback; Acquire echo detection data from each sensing task node: As a form of sensory feedback; Monitor uplink pilot received power and interference noise level: ; as feedback for conflict verification.

[0057] After the pilot configuration is issued, S312 continuously collects three types of feedback information through a monitoring cycle for subsequent conflict identification and repair decisions. This can be understood as an operational effect recovery and verification mechanism. Specifically, after the pilot configuration is issued to each terminal through downlink control signaling and takes effect, the system enters a preset monitoring cycle. During this monitoring period, the system continuously collects operational data from the network and terminal sides, mainly including three types of feedback information: First, the system obtains channel state information from each terminal, reflecting the channel estimation effect under pilot action, such as channel response changes and estimation stability, used to determine whether the current pilot allocation can support the normal communication training process; this type of data serves as training feedback. Second, the system obtains echo detection data from nodes performing sensing tasks, such as target echo intensity and detection result stability, used to assess whether pilot reuse affects sensing performance; this type of data serves as sensing feedback. Third, the system continuously monitors the received power of pilot signals and the corresponding interference noise level at the receiving end, used to determine whether there are collisions or strong interference phenomena between pilots, such as abnormal enhancement of certain pilot signals or a significant increase in noise levels; this type of data serves as conflict verification feedback. By synchronously acquiring these three types of feedback information within the same monitoring period, the system can comprehensively evaluate the current pilot allocation scheme from three dimensions: communication training effect, sensing task effect, and actual interference performance, providing a basis for subsequent conflict identification, conflict map updates, and local repair. This represents the pilot color mapping table. Indicates the first One terminal, Indicates assignment to the terminal pilot colors, Represents the set of pilot resources. Indicates the scheduled monitoring period. Indicates terminal The set of channel state information, Indicates time Channel state parameters, Indicates the first A collection of echo detection data for a sensing task. Indicates time Sensing echo data, Indicates terminal At any moment The received pilot power, This indicates the corresponding level of interference noise.

[0058] S32, Conflict Identification and Graph Structure Update: S321, Calculate the terminal channel estimation error based on training feedback: ; When satisfied At that time, determine the terminal The node is colored as a failure.

[0059] S321 utilizes training feedback to evaluate the channel estimation performance of each terminal after pilot allocation, identifying failed nodes due to pilot conflicts or interference. Specifically, after the pilot configuration takes effect, the system analyzes the channel estimation results of each terminal based on the channel state information reported by the terminals, comparing the currently estimated channel state with the actually observed channel performance to assess the accuracy of the channel estimation. If a terminal's channel estimation result deviates significantly from the actual channel state, it indicates that the terminal has experienced significant interference during pilot training, leading to channel estimation distortion. The system sets an acceptable error range for this deviation. When a terminal's channel estimation error exceeds this range, it is considered that the current pilot allocation has failed for that terminal and cannot support the normal channel estimation process. At this time, the terminal is marked as a failed node. In this way, abnormal terminals caused by pilot conflicts or interference can be automatically identified during actual operation, providing a direct basis for subsequent adjustments to pilot allocation and updates to conflict relationships. Indicates terminal Channel estimation error, Indicates the estimated channel. Indicates the real channel, This represents the channel estimation error threshold.

[0060] S322, based on perception feedback, calculates perception performance metrics: ; When adjacent terminal pilot reuse leads to When this occurs, it is determined that there are newly added perceptual coupling conflict edges between the corresponding terminals: ; S322 utilizes sensing feedback to evaluate the impact of pilot reuse on sensing task performance and identify whether new sensing coupling conflicts have arisen. Specifically, after the pilot configuration takes effect, the system continuously acquires echo detection data from the nodes performing the sensing tasks, such as target echo intensity, background noise level, and detection result stability. Based on this data, the system evaluates the performance of each sensing task, focusing on the sensing signal quality and target detection effect. During the evaluation process, the system determines whether the sensing signal is affected by interference from pilot reuse by other terminals. If multiple terminals reuse the same pilot, causing interference with the sensing echo signal, an increase in noise level, or a decrease in target detection results, the system will detect the interference. For example, if there are issues such as unstable detection or increased missed detections, it indicates that the current pilot reuse is negatively impacting the sensing task. The system sets an acceptable minimum standard for sensing performance. When the sensing signal quality falls below this standard, or the target detection effect degrades beyond the allowable range, it is determined that a new sensing coupling conflict exists between the terminals currently participating in pilot reuse. A new limited reuse conflict edge is added between the corresponding terminals in the pilot conflict constraint graph to constrain subsequent pilot allocation and prevent reuse situations that affect sensing performance from recurring. In this way, the impact of pilot reuse on the sensing task can be dynamically perceived, and the conflict relationship model can be adjusted in a timely manner, making pilot allocation more balanced between communication and sensing performance. This represents the perceived signal-to-interference-plus-noise ratio (SIR). Indicates the power of the sensed signal. Indicates interference power. Indicates noise power. This represents the probability of target detection. This represents the perceived signal-to-interference-plus-noise ratio (SINR) threshold. This represents the detection probability threshold. This indicates the addition of a sharp edge.

[0061] S323, Calculate pilot interference intensity based on collision verification feedback: ; When satisfied Furthermore, if it occurs continuously across multiple time slots, the terminal is determined. With terminal There are newly added link interference conflict edges:

[0062] in, Indicates the interference intensity index; This indicates the threshold for determining interference.

[0063] The S323 scheme utilizes the actual pilot signal performance at the receiving side to determine the existence of persistent link interference and identify new interference conflicts. Specifically, after the pilot configuration takes effect, the system continuously monitors the received power of the pilot signals from each terminal and the corresponding interference noise level at the receiving end. By comparing the pilot signal strength with the background interference level, it can determine whether there is abnormal interference in the current pilot environment. During monitoring, if it is found that the interference component in the received signal of a pair of terminals is enhanced when using pilot signals—for example, abnormal pilot signal fluctuations, persistently high noise levels, or unstable demodulation results—it indicates that there may be pilot conflicts or strong interference between these two terminals. To avoid misjudgments caused by occasional interference, the system does not make direct judgments based on a single detection result but instead observes over multiple consecutive time slots. If similar interference phenomena occur in multiple consecutive time slots, such as pilot interference being persistent or occurring periodically, then the interference can be considered to be stable and repetitive. When the above-mentioned persistent interference condition is met, the system determines that a new link interference conflict relationship has been formed between the two terminals, and adds a conflict edge to the two terminals in the pilot conflict constraint graph. At the same time, the conflict relationship is marked as a high-intensity interference type for strict constraint during subsequent pilot allocation to avoid pilot conflict from occurring again.

[0064] S324, based on the identified set of failed colored nodes: ; And the newly added set of conflicting edges: ; Pilot conflict constraint diagram: ; Perform operations such as adding, deleting, or changing the type of nodes and edges to obtain the updated conflict graph: ; in, Represents the set of ineffective colored nodes. This represents the newly added set of conflicting edges. This represents the updated conflict diagram.

[0065] S33, Local Repair Shading and Scheme Update: S331, based on the updated conflict diagram Identify the affected subgraphs: ; in, ; ; Perform repair coloring only on the affected subgraphs, maintaining: ; in, Indicates the affected subgraph. Represents the set of nodes in a subgraph. Represents the set of edges of a subgraph. Represents the set of adjacent nodes of the failed node; S332, during the restoration and coloring process, define the color adjustment cost function: ; in, This represents the color adjustment cost function. The indicator function is defined by minimizing the color adjustment cost function. Prioritize inheriting existing pilot colors that do not conflict, and perform local color adjustments on unusable colors to satisfy: And it satisfies the limited reuse constraint.

[0066] The core objective of the S332 scheme is to perform pilot reallocation with minimal cost only in the locally affected area after a conflict or failure occurs. This aims to minimize the overall adjustment while ensuring conflict resolution. Specifically, the system determines which terminals are affected based on the failed colored nodes and newly added conflict edges identified in the previous step. These terminals and their directly related adjacent terminals are then extracted to form a local subgraph. This subgraph represents the area requiring repair, while other unaffected terminals retain their original pilot allocations. During the repair process, the system first checks whether the currently allocated pilots for each affected terminal still satisfy the conflict constraints. If a pilot is still usable under the current conflict relationship, it is retained without adjustment. Pilot replacement is only performed on a terminal when the original pilot conflicts with the newly added conflict relationship. When replacing pilot signals, the system will try to select the alternative with the least change from the original pilot signals. For example, it will prioritize pilot resources that will not affect stable terminals and will not introduce new conflicts. The entire adjustment process aims to modify as few terminals as possible, reducing the overhead of system retraining and switching. In this way, the changes in the pilot allocation scheme can be kept to a minimum while ensuring that all conflicts are eliminated, thereby improving the stability and continuity of system operation. After completing the local repair, the system will reorganize the updated terminal and pilot correspondence, generate a new pilot color mapping table, and update the pilot allocation scheme synchronously for use in subsequent network scheduling cycles.

[0067] S333, final update of pilot color mapping table: ; And pilot allocation scheme: ; This represents the updated pilot color map. This indicates the updated pilot allocation scheme.

[0068] This invention encompasses any substitutions, modifications, equivalent methods, and solutions made within the spirit and scope of this invention. To provide the public with a thorough understanding of this invention, specific details are described in detail in the following preferred embodiments; however, those skilled in the art will fully understand the invention even without these details. Furthermore, to avoid unnecessary misunderstanding of the essence of this invention, well-known methods, processes, procedures, components, and circuits are not described in detail.

[0069] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A pilot conflict optimization allocation method based on graph coloring mechanism, characterized in that, Includes the following steps: S1: Constructing a pilot conflict constraint graph: Obtaining the set of terminals to be assigned, the set of sensing tasks, and the set of pilot resources in the target sensory network; Based on the link interference relationship, perception coupling relationship and security risk relationship in the set of terminals to be assigned, the pilot non-reusability relationship and pilot limited reusability relationship between each terminal are identified, forming a pilot conflict constraint graph with nodes as terminals to be assigned and edges as conflict constraints; and a conflict priority identifier is generated for each node in the pilot conflict constraint graph, and a conflict type identifier is generated for each edge, to obtain a conflict graph to be colored. S2: Perform layered graph coloring optimization allocation: Input the conflict graph to be colored into the graph coloring allocation engine. Based on the conflict priority identifier and conflict type identifier, first perform strong constraint coloring on the pilot absolute conflict edges, and then perform conditional coloring on the pilot limited reuse edges to obtain the initial coloring result. Subsequently, considering the requirements for perception isolation, security disturbance, and historical coloring continuity, the initial coloring result is subjected to color rearrangement, local color replacement, and generation of private pilot additional identifiers, and the pilot color mapping table and pilot allocation scheme are output. S3: Implement pilot signal distribution and conflict resolution: Distribute pilot signal configurations to the corresponding terminals according to the pilot signal color mapping table and pilot signal allocation scheme, and collect training feedback, perception feedback and conflict verification feedback after pilot signal execution; Based on the training feedback, perception feedback, and conflict verification feedback, the failed colored nodes and newly added conflict edges are identified. The pilot conflict constraint graph is locally updated, and only the affected subgraphs are repaired and colored. The updated pilot allocation scheme is then output.

2. The pilot conflict optimization allocation method based on graph coloring mechanism according to claim 1, characterized in that, S1 specifically includes: S11: Obtain the list of active terminals in the target sensor network from the network management module as the terminal set to be assigned, obtain the current sensing tasks to be executed and the sensing range and sensing accuracy requirements from the sensing task queue as the sensing task set, and obtain the currently idle pilot sequence codebook from the resource pool as the pilot resource set. S12: Based on the spatial distance between each pair of terminals in the set of terminals to be assigned, the beam pointing overlap, and the signal-to-interference-plus-noise ratio prediction at the receiving end, determine whether there is a link interference relationship; based on whether the sensing tasks associated with each pair of terminals have overlapping sensing coverage areas or collaborative sensing targets, determine whether there is a sensing coupling relationship; based on the trust level difference between each pair of terminals, the sensitivity of historical access locations, and whether there are scenarios of simultaneous access to the core security area, determine whether there is a security risk relationship. S13: If there is a link interference relationship or a high-risk relationship in the security risk relationship between the two terminals, it is determined that there is a pilot non-reusable relationship between the two, and an absolute conflict edge is constructed between the corresponding nodes in the graph; if there is a perception coupling relationship or a general concern relationship in the security risk relationship between the two terminals, it is determined that there is a pilot limited reuse relationship between the two that allows reuse under limited conditions, and a limited reuse edge is constructed between the corresponding nodes in the graph; thus forming a pilot conflict constraint graph with nodes as terminals to be allocated and edges as conflict constraints.

3. The pilot conflict optimization allocation method based on graph coloring mechanism according to claim 2, characterized in that, The determination of whether a link interference relationship exists specifically includes: Acquire the spatial location information, communication beam pointing information, and current communication parameters of the two terminals to be assigned; calculate the spatial distance between the two terminals based on the spatial location information, and determine whether the spatial distance is less than the preset interference distance threshold; The communication beam pointing information is used to determine the coverage area of ​​the communication beams of the two terminals to be assigned, and it is determined whether there is spatial overlap in the coverage area of ​​the communication beams exceeding the preset overlap ratio threshold; the received signal-to-interference-plus-noise ratio between the two terminals to be assigned is predicted based on the communication parameters, and it is determined whether the predicted signal-to-interference-plus-noise ratio is lower than the preset signal-to-interference-plus-noise ratio threshold. When the spatial distance is less than the preset interference distance threshold, or the overlap ratio of the communication beam coverage area exceeds the preset overlap ratio threshold, or the predicted signal-to-interference-plus-noise ratio is lower than the preset signal-to-interference-plus-noise ratio threshold, it is determined that there is a link interference relationship between the two terminals to be allocated, and the corresponding terminal node pair is marked as a pilot conflict candidate relationship.

4. The pilot conflict optimization allocation method based on graph coloring mechanism according to claim 2, characterized in that, S1 further includes: Based on the service priority, mobility speed, or channel time-varying characteristics of each terminal, a conflict priority identifier is generated for each node in the pilot conflict constraint graph; based on the interference intensity, coupling tightness, or risk level corresponding to each edge, a conflict type identifier is generated for each edge, resulting in a conflict graph to be colored.

5. The pilot conflict optimization allocation method based on graph coloring mechanism according to claim 1, characterized in that, S2 specifically includes: S21: Input the conflict graph to be colored into the graph coloring assignment engine, traverse all edges in the graph with conflict type identifiers; prioritize the processing of connection relationships marked as absolute conflict edges, determine the coloring order according to the conflict priority identifier of each node, assign different pilot colors to adjacent nodes with absolute conflict edges, and ensure pilot orthogonality under strong constraints. S22: Based on the absolute conflict edge constraint, perform conditional coloring on the connection relationship marked as limited reuse edge; according to the perception coupling tightness or security concern level associated with the limited reuse edge, set the interference tolerance threshold, and determine whether the two end nodes can reuse the same pilot color under the premise of meeting the perception isolation requirements or security disturbance requirements; if the condition is met, reuse is allowed; otherwise, different colors are assigned, and the initial coloring result is generated. S23: Obtain the coverage area of ​​the sensing task in the current network topology as the sensing isolation requirement, obtain the terminal distribution density and security area distribution as the security disturbance requirement, and obtain the pilot color of each terminal in the previous scheduling cycle as a historical coloring continuity reference; based on the sensing isolation requirement, rearrange the spatial distribution of nodes of the same color in the initial coloring result to reduce sensing interference; based on the security disturbance requirement, locally change the color of the nodes around the high-risk area to improve anti-interception capability; based on the historical coloring continuity, perform inheritance adjustment on the color of the handover or re-access terminal; generate a private pilot additional identifier for the terminal carrying the sensing task or security sensitive service, indicating that a private pilot sequence is superimposed on the public pilot; finally output a pilot color mapping table including the correspondence between terminal identifier and pilot color, and a pilot allocation scheme including the specific pilot sequence allocation result.

6. The pilot conflict optimization allocation method based on graph coloring mechanism according to claim 5, characterized in that, The step of determining the coloring order based on the conflict priority identifier of each node includes reading all nodes in the conflict graph to be colored and obtaining the conflict priority identifier corresponding to each node; sorting all nodes according to the value of the conflict priority identifier, and arranging the nodes in descending order of the conflict priority identifier value; when there are nodes with the same conflict priority identifier value, secondary sorting is performed according to the number of conflict edges associated with the node or the node connectivity. After sorting, a node processing sequence is generated as the node coloring order of the graph coloring allocation engine. The graph coloring allocation engine performs pilot color allocation on each node in sequence according to the node processing sequence, so that the node with the higher conflict priority value completes pilot coloring first, thereby reducing the probability of conflict in the subsequent node coloring process.

7. The pilot conflict optimization allocation method based on graph coloring mechanism according to claim 5, characterized in that, The setting of an interference tolerance threshold to determine whether the two nodes can reuse the same pilot color under the premise of meeting the requirements of perception isolation or security disturbance specifically includes: Based on the communication quality requirements of the target sensor network and the pilot channel estimation accuracy requirements, a minimum signal-to-interference-plus-noise ratio requirement is set as the basic signal quality threshold. Based on network type, terminal service type, and sensing task accuracy requirements, the basic signal quality threshold is graded and corrected to obtain a basic interference tolerance level that matches the service scenario. The basic interference tolerance level is dynamically adjusted based on the current network load level, terminal spatial distribution density, and interference environment intensity to generate the interference tolerance threshold for the current scheduling period. When performing pilot condition reuse determination, the predicted signal-to-interference-plus-noise ratio (SINR) between two terminals connected through a limited reuse edge is obtained, and the predicted SINR is compared with the interference tolerance threshold. When the predicted SINR is not lower than the interference tolerance threshold, the pilot reuse condition is determined to be met. When the predicted SINR is lower than the interference tolerance threshold, the pilot reuse condition is determined not to be met, thereby guiding the pilot color allocation decision.

8. The pilot conflict optimization allocation method based on graph coloring mechanism according to claim 1, characterized in that, S3 specifically includes: S31: Based on the correspondence between terminal identifiers and pilot colors in the pilot color mapping table, select the corresponding pilot sequence from the pilot resource set and send the pilot configuration to the corresponding terminal through downlink control signaling; within the predetermined monitoring period after the pilot configuration is executed, collect the channel state information reported by each terminal as training feedback, collect the echo detection data of each sensing task node as sensing feedback, and monitor the uplink pilot received power and interference noise level as collision verification feedback; S32: Based on the training feedback analysis, analyze the channel estimation quality of each terminal. If the channel estimation error of a terminal exceeds a preset threshold, the corresponding terminal is determined to be a failed colored node due to interference. Based on the perception feedback analysis, analyze the detection signal-to-interference-plus-noise ratio or target detection probability of the perception task. If the pilot reuse of adjacent terminals causes the perception performance to degrade beyond the tolerance threshold, it is determined that there is a newly added perception coupling conflict edge between the two terminals. Based on the conflict verification feedback, detect whether there is a demodulation failure event caused by pilot collision. If periodic or continuous pilot interference occurs between a pair of terminals, it is determined that there is a newly added link interference conflict edge between them. According to the identified failed colored nodes and newly added conflict edges, add, delete, or change the type of the corresponding nodes and edges in the pilot conflict constraint graph to achieve local graph update. S33: Determine the scope affected by the local update, extract the subgraph including the failed colored nodes and their adjacent nodes, as well as the nodes associated with the newly added conflicting edges, as the affected subgraph; keep the pilot colors of other nodes outside the affected subgraph unchanged, and only perform repair coloring on the affected subgraph; during the repair coloring process, prioritize inheriting the colors that have not caused conflicts in the original color allocation, and perform local color adjustment on the unusable colors caused by failed nodes or newly added conflicting edges, so as to achieve pilot conflict resolution of all nodes in the subgraph with the minimum color adjustment cost; update the pilot color mapping table and pilot allocation scheme based on the repair coloring results, and output the updated pilot allocation scheme for use in the next scheduling cycle.

9. The pilot conflict optimization allocation method based on graph coloring mechanism according to claim 8, characterized in that, The determination that a new perceptual coupling conflict exists between the two terminals specifically includes: The system acquires echo detection data and corresponding sensing result data of each node performing the sensing task after the pilot configuration takes effect, and evaluates the signal quality and target detection effect of each sensing task. For terminal combinations participating in pilot reuse, the system analyzes the changes in sensing performance before and after pilot reuse, and identifies whether there is a decrease in sensing signal quality or a deterioration in detection effect caused by pilot reuse. The system tracks and judges the changes in sensing performance over multiple consecutive observation periods. When the sensing signal quality is detected to be continuously lower than the preset requirements or the target detection effect is continuously decreased and exceeds the tolerance range, it is determined that there is a stable sensing interference relationship between the corresponding terminals. Based on the judgment result, a limited reuse conflict edge is added between the corresponding terminal nodes in the pilot conflict constraint graph to represent the newly added sensing coupling conflict relationship and to constrain the subsequent pilot allocation process.

10. The pilot conflict optimization allocation method based on graph coloring mechanism according to claim 8, characterized in that, The specific steps for resolving pilot conflicts for all nodes within a subgraph with minimal color adjustment cost include: Extract the affected subgraph based on the failed colored nodes and newly added conflict edges, and keep the original pilot colors of each node outside the affected subgraph unchanged; check the availability of the currently assigned pilot colors of each node in the affected subgraph one by one, and retain the original pilot colors when the original pilot colors still meet the updated conflict constraints. When the original pilot color does not meet the updated conflict constraints, the corresponding node is identified as a node to be adjusted. For each node to be adjusted, candidate colors that will not cause pilot conflicts with adjacent nodes are selected from the currently available pilot colors, and candidate colors that can keep the colors of adjacent stable nodes unchanged and will not cause new conflicts are selected as replacement colors. When multiple candidate colors meet the conflict resolution requirements, the candidate color that results in the fewest color change nodes and the smallest color transfer adjustment range is selected first. The pilot color redistribution of each node to be adjusted in the affected subgraph is completed in the above manner until all nodes in the affected subgraph meet the conflict constraint conditions, so as to achieve pilot conflict resolution of all nodes in the subgraph with the minimum color adjustment cost.

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