A two-way short message communication method for non-network scenarios

Abstract

The present invention discloses a two-way short message communication method for a network-free scenario, relates to the field of communication technology, and is used to solve the problem of poor communication in a network-off scenario. The present invention realizes real-time evaluation of the accessibility of the communication environment and dynamically judges the stability of the public network link through multi-source environment perception and link status fusion modeling, providing support for channel switching. A scheduling scoring model is constructed by combining link status and task characteristics, so that the terminal gives priority to transmitting high-urgency and high-adaptation tasks under link-restricted conditions, thereby improving resource utilization efficiency. A multi-timescale risk integration mechanism is introduced to improve the recognition ability of sudden states such as falling, stillness, and sudden changes in air pressure, and automatically generates emergency short messages without human intervention, realizing the rapid upload of SOS information and location, thereby improving the stability, security and adaptability of communication in a network-free scenario.

Description

Technical Field

[0001] The present invention relates to the field of communication technology, and more particularly to a two-way short message communication method for use in a non-network scenario. Background Art

[0002] In extreme operating environments such as routine power grid inspections, mountainous operation and maintenance, and sudden natural disasters, public network communication infrastructure is often completely unavailable due to geographical obstructions, signal coverage blind spots, or sudden interruptions. This results in the inability of operating terminals to upload operating status, feedback location information, and return alarm events at critical moments, seriously threatening the closed-loop execution of dispatch instructions and the safety of personnel operations. This is especially true in areas without public network signal coverage, such as mountain cliffs, tunnels, and forests. Traditional cellular network-based communication mechanisms completely fail and are unable to provide basic two-way information transmission channels.

[0003] Deficiencies in existing technologies: The Beidou satellite navigation system features short message communication, providing a viable solution for information transmission in environments without a public network. However, existing short message communication technologies often rely on manual triggering or fixed-period reporting, lacking adaptive sensing capabilities for environmental changes and automatic triggering mechanisms for emergency situations. This makes it difficult to address issues such as "communication preemption," "status overflow," and "link lag" during emergencies. Furthermore, existing solutions generally lack strategies for jointly evaluating and analyzing communication link status and communication tasks, leading to inaccurate communication resource scheduling, irrational priority allocation, and delayed emergency response. Summary of the Invention

[0004] In order to overcome the above-mentioned defects of the prior art, there is a solution as follows to solve the problem of poor communication in the network interruption scenario described in the background art.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A two-way short message communication method for a non-network scenario comprises the following steps:

[0007] Based on the multi-source sensor data integrated by the terminal, a disturbance tensor structure is constructed, and a communication reachability score is generated through nonlinear mapping. Combined with the sliding window, sudden changes in the communication environment are detected.

[0008] A communication state vector is constructed based on the 4G link activity score factor. Based on the combined judgment of the communication reachability score and the 4G link activity score, an asymmetric hysteresis switching strategy is implemented to complete the primary and backup channel switching between the public network communication channel and the Beidou short message channel.

[0009] Extract attribute vectors from scheduled tasks, construct a nonlinear priority scoring function, generate task scheduling subsets under communication resource constraints, and perform structure mapping and format compression processing based on the main channel type to form transmission task packages that can adapt to the link;

[0010] Continuously monitor risk factors and perform risk scoring, combine multi-time scale integration windows to analyze risk trends and determine high-confidence abnormal states. Once a high-confidence abnormal state is confirmed, a minimum-structured emergency short message is generated and sent preferentially through the Beidou link.

[0011] In a preferred embodiment, a disturbance tensor structure is constructed based on multi-source sensor data integrated by the terminal, and the specific steps include:

[0012] The sensor modules integrated into the terminal collect on-site environmental information. The sensors used include air pressure sensor, three-axis accelerometer, geomagnetic sensor, gyroscope, light sensor, infrared or ultrasonic ranging sensor;

[0013] The sensor data output by each type of sensor is mapped to a unified scale to obtain the environmental standardized feature vector;

[0014] When the terminal moves, rotates rapidly, or experiences abnormal magnetic disturbances in its spatial orientation, the acceleration modulus is used as a disturbance factor. The gradient change of the geomagnetic vector is used to represent the intensity of the magnetic space disturbance. Combined with the attitude angle change, a three-dimensional cross-mapping is formed to construct a three-dimensional disturbance tensor structure to capture the joint disturbance trend.

[0015] In the three-dimensional perturbation tensor structure, the value of each element is determined by a nonlinear combination of three types of perturbation factors. The acceleration factor is placed in the denominator as a perturbation excitation term, and the mutation behavior is enhanced by an exponential function. The attitude angle change and the magnetic space perturbation intensity term are placed in the numerator as weight control terms.

[0016] In a preferred embodiment, a communication reachability score is generated by nonlinear mapping, and a sliding window is used to detect sudden changes in the communication environment. The specific steps include:

[0017] After completing the construction of the environment normalized feature vector and the disturbance structure tensor, these two types of data are fused and mapped into a communication link reachability indicator space;

[0018] For each sensor eigenvalue, a corresponding response adjustment factor is introduced and mapped using the hyperbolic tangent function of the saturation interval;

[0019] The extreme value of the disturbance in the disturbance structure tensor is extracted and used as the global disturbance term. By combining it with the sensor eigenvalue term, the total input value of the scoring function is constructed.

[0020] The extreme value of disturbance is input as the disturbance sensitivity factor, dominating the low value interval of the scoring function;

[0021] The combined result is input into a nonlinear boundary-preserving function, the linear superposition result is compressed and mapped into the interval [0, 1], and the communication reachability score factor is output;

[0022] A fixed-length scoring record window is maintained inside the terminal using a sequential sliding window mechanism. Every time a new communication reachability score is received, the difference between it and the communication reachability score result at the previous moment in the window is calculated. If the current score drops by more than the set drop threshold, a communication mutation flag is generated and used as a communication environment mutation behavior.

[0023] In a preferred embodiment, a communication state vector is constructed based on the 4G link activity score factor, and an asymmetric hysteresis switching strategy is executed based on the joint judgment result of the communication reachability score and the 4G link activity score. The specific steps include:

[0024] The communication reachability score is used as an environmental factor for channel switching, and the 4G link activity score factor is introduced as a communication state vector to evaluate signal stability and location disturbance trends.

[0025] The 4G link activity score represents the dynamic communication status of the current public network link. The signal stability of the 4G link activity score is determined by continuously recording the changes in the 4G signal strength received by the terminal within a given monitoring period and calculating the rate of decrease in received power per unit time. Based on the continuous position point sequence of the terminal positioning module, the spatial displacement amplitude within the same period is calculated to determine the position disturbance trend of the terminal in physical space. A weighted combination structure is then used to construct the 4G link activity score function.

[0026] The communication reachability score and the 4G link activity score are combined to form the link state vector. The communication reachability score reflects the physical feasibility of the environment for the link, while the 4G link activity score reflects the stability of the signal behavior of the network itself.

[0027] A segmented hysteresis switching strategy is set according to the link state vector.

[0028] In a preferred embodiment, completing the primary and backup channel switching between the public network communication channel and the Beidou short message channel includes the following steps:

[0029] When the communication accessibility score exceeds 0.8, it is determined to be in a high reachability state and the current 4G main link communication is maintained; when the communication accessibility score is lower than 0.5, it is determined to be in a low reachability state and the channel switching strategy is triggered to switch to the Beidou short message link; when the communication accessibility score is less than or equal to 0.8 and greater than or equal to 0.5, it is in a switching hysteresis state and does not switch immediately, entering the monitoring buffer period;

[0030] The 4G link activity score is used as an auxiliary judgment basis. If the 4G link activity score shows a negative growth trend, the channel switching strategy is triggered and the backup channel is switched in advance.

[0031] After switching to the backup channel, the structure of the current communication task is adapted and adjusted;

[0032] Build a communication task structure mapping mechanism to classify the currently pending tasks into first-class tasks, second-class tasks, and third-class tasks according to their priorities;

[0033] When switching to the Beidou link, the necessary fields in a type of task are extracted to form a structure. The necessary fields include terminal number, longitude and latitude position, alarm type identifier, timestamp and scene feature code to avoid exceeding the short message capacity limit.

[0034] In a preferred embodiment, extracting attribute vectors for the tasks to be scheduled and constructing a nonlinear priority scoring function include the following steps:

[0035] The task structure is abstracted into an attribute vector, which includes task generation time, maximum delay time, data volume, task urgency, and link reachability score;

[0036] After the task attribute vector is constructed, the task scheduling is sorted and a nonlinear priority scoring function is constructed;

[0037] The priority scoring function is used to quantify the scheduling value of each task under the current communication state, and is calculated by jointly modeling the task attributes and the network state;

[0038] Extract the urgency, generation time, maximum delay time, and communication reachability score of each task to be scheduled;

[0039] A nonlinear function is used to construct a time modulation term. The difference between the task generation time and the current system time is used as input, multiplied by the adjustment parameter and used as the variable of the exponential function to generate the time effect score of the task.

[0040] Evaluate the task's transmittability under link conditions by multiplying the task's maximum allowable delay time by the link reachability score. The result is input into a nonlinear response function and mapped into a transmittability score. The transmittability score reflects whether the task is currently transmitted.

[0041] The time effect score and the transmission feasibility score are structurally combined, and the normalized score value is output as the priority score through the boundary compression function, which is limited between 0 and 1.

[0042] In a preferred embodiment, generating a task scheduling subset under communication resource constraints, and performing structure mapping and format compression processing according to the main channel type to form a transmission task package that can adapt to the link includes the following steps:

[0043] The available transmission capacity threshold for the current scheduling period is set based on the primary communication channel type. The available transmission capacity threshold is the upper bound of the scheduling window, reflecting the total amount of data that can be transmitted per unit time under the current link conditions. For 4G links, the available transmission capacity threshold can be determined based on real-time bandwidth assessment results. For Beidou short message links, the available transmission capacity threshold is a fixed maximum message length.

[0044] The bandwidth capability identifier of the current communication channel and the scheduling cycle time length are multiplied to obtain the allocable communication budget as the transmission capacity;

[0045] The bandwidth capability identifier is the estimated value of the 4G network rate or the maximum load of the Beidou short message, and the scheduling cycle time length is the maximum transmission time available for the current communication scheduling;

[0046] Sort the calculated task priority scores in descending order to form a task scheduling queue. Select the task with the highest score from the head of the queue in turn, and accumulate the data volume until the total amount exceeds the current window capacity limit. Then stop task selection and form a subset of the current scheduling cycle as the task scheduling subset.

[0047] Identify the current primary communication channel type to form an adaptable link transmission task packet. If it is a 4G public network link, no compression mapping processing is required;

[0048] If the current main channel is the Beidou short message link, the scheduling task performs structure compression and field reduction processing to form a transmission task package. The field reduction processing includes field screening and reconstruction, field coding compression, field alignment and byte control.

[0049] In a preferred embodiment, risk factors are continuously monitored and risk scores are performed, and risk trends are combined with multi-time scale integration windows to determine high-confidence abnormal states, including the following steps:

[0050] Construct anomaly detection factors for different risk scenarios, and construct and process nonlinear combination risk scoring functions for the anomaly detection factors. The risk scoring function is used to assess the potential abnormal state level of the terminal in the current environment.

[0051] All anomaly detection factors are first normalized and nonlinearly amplified using the hyperbolic tangent function. The output values of all factors after nonlinear amplification are combined and aggregated through exponential mapping to obtain a risk score.

[0052] Based on time, three time windows are set, which correspond to time window lengths of seconds, ten seconds, and minutes respectively;

[0053] In each time window, the risk score is accumulated over the entire time period covered by the window, and a risk threshold is set for each time window to conduct continuous risk behavior detection;

[0054] If the cumulative risk scores of at least two of the three time windows exceed the respective set risk thresholds at the same time, it is determined that the current terminal is in a high-confidence abnormal state.

[0055] In a preferred embodiment, when a high-reliability abnormal state is confirmed, a minimum-structured emergency short message is generated and preferentially sent via the Beidou link, including the following steps:

[0056] When the high-confidence abnormal state triggering conditions are met, the emergency short message construction process is immediately started to generate the minimum structured communication data content, and a high-priority emergency sending request is initiated through the Beidou short message channel.

[0057] The technical effects and advantages of the present invention are as follows:

[0058] The present invention realizes real-time quantitative assessment of the accessibility of the communication environment through multi-source environmental perception and link status fusion modeling, can dynamically judge the stability and effectiveness of the public network link, and provide data support for the switching of communication channels. Secondly, the scheduling scoring model constructed based on link status and task characteristics enables the terminal to give priority to transmitting high-urgency and high-adaptability tasks under link-restricted conditions, avoid low-value tasks from occupying key communication resources, and improve the efficiency of communication resource utilization. In addition, by introducing a multi-time scale risk integration mechanism, the recognition accuracy of sudden states such as falling, stillness, and sudden changes in air pressure is improved, and structured emergency short messages can be automatically generated without human intervention, ensuring that SOS information can be quickly uploaded and the location is returned when the public network is interrupted or personnel lose contact, thereby improving the stability, security and engineering adaptability of two-way communication in network-free scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1 The present invention is a flowchart of a two-way short message communication method for a non-network scenario. DETAILED DESCRIPTION

[0060] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0061] In order to achieve the above objectives, Figure 1 A schematic structural diagram of a two-way short message communication method for a non-network scenario is provided in the present invention, which specifically includes the following steps:

[0062] Based on the multi-source sensor data integrated by the terminal, a disturbance tensor structure is constructed, and a communication reachability score is generated through nonlinear mapping. Combined with the sliding window, sudden changes in the communication environment are detected.

[0063] A communication state vector is constructed based on the 4G link activity score factor. Based on the combined judgment of the communication reachability score and the 4G link activity score, an asymmetric hysteresis switching strategy is implemented to complete the primary and backup channel switching between the public network communication channel and the Beidou short message channel.

[0064] Extract attribute vectors from scheduled tasks, construct a nonlinear priority scoring function, generate task scheduling subsets under communication resource constraints, and perform structure mapping and format compression processing based on the main channel type to form transmission task packages that can adapt to the link;

[0065] Continuously monitor risk factors and perform risk scoring, combine multi-time scale integration windows to analyze risk trends and determine high-confidence abnormal states. Once a high-confidence abnormal state is confirmed, a minimum-structured emergency short message is generated and sent preferentially through the Beidou link.

[0066] In an environment without public network communications, power grid operation and maintenance terminals face complex uncertainties such as sudden channel interruptions, terrain obstructions, and environmental interference. Therefore, it is necessary to implement an adaptive communication reachability prediction mechanism within the terminal. This mechanism needs to use multiple raw sensor signals as input and generate link status scores in real time through fusion modeling. This provides a basic judgment basis for subsequent link switching, emergency short message triggering, and resource scheduling strategies.

[0067] Step 1: Collect and fusion model multi-source environmental data:

[0068] First, the terminal integrates multiple sensor modules to collect on-site environmental information. These sensors include, but are not limited to, air pressure sensors (to reflect changes in altitude and airtightness), triaxial accelerometers (to capture sudden changes in a person's state), geomagnetic sensors (to perceive spatial disturbances), gyroscopes (to estimate changes in spatial posture), light sensors (to determine the degree of occlusion), and infrared or ultrasonic ranging sensors (to identify local, confined spaces). The raw data output by each sensor type can vary in units, dimensions, and dynamic ranges, necessitating unified mapping of all sensor data for subsequent modeling.

[0069] Each raw sensor output value is first compressed through a logarithmic function with a constant as the base, and then a stretching factor related to the sensor response sensitivity is superimposed (which varies depending on the sensor setting). This maintains the dynamic distribution characteristics of the signal in each dimension while avoiding boundary compression distortion. All the perceived features after mapping are encapsulated into an environmentally standardized feature vector as the first-level data output of this step.

[0070] Perform perturbation behavior modeling and structured tensor generation:

[0071] The impact of environmental factors on communication links is often not a static single-point interference, but rather the result of a multivariate joint disturbance. Therefore, after completing scale unification, it is necessary to further establish a disturbance characteristic tensor structure from the perspective of dynamic changes. This structure is used to characterize the coupling behavior between the terminal's current posture (three-dimensional angular changes represented by a combination of Euler angles), geomagnetic gradient disturbances, and acceleration mutation intensity.

[0072] Specifically, when the terminal moves violently, rotates rapidly, or experiences abnormal magnetic disturbances in its spatial orientation, these factors jointly indicate that there may be severe disturbances in the communication environment or channel interference. To achieve modeling, the acceleration modulus is used as a disturbance factor, and the local gradient change of the geomagnetic vector is used to represent the intensity of the magnetic space disturbance. Combined with the attitude angle change, a three-dimensional cross-mapping is formed to construct a three-dimensional disturbance tensor structure that can be used to capture the joint disturbance trend. In this disturbance tensor structure, the value of each element is determined by a nonlinear combination of three types of disturbance factors. The acceleration factor is placed in the denominator as a disturbance excitation term, and the mutation behavior is enhanced by an exponential function. The attitude angle change and the magnetic space disturbance intensity term are placed in the numerator as weight control terms.

[0073] For example, a power grid operator carrying a smart terminal is inspecting a high-voltage tower in a mountainous area. When the terminal suddenly slips downhill, the terminal will experience the following typical physical characteristics: a rapid increase in the acceleration modulus: from a stable 1.0g to 2.5g, indicating a slip or fall; the gyroscope detects a short-term change in the roll angle from 0° to 70°, indicating a sudden change in the terminal's orientation; and a sharp increase in the rate of change of the geomagnetic vector, possibly due to magnetic field disturbances caused by proximity to metal structures or entry into enclosed spaces.

[0074] The above three changes indicate that the current environment may have changed from a stable inspection state to an abnormal state, which may have affected the stability of the communication channel. Immediate communication link adaptation and short message preparation are required.

[0075] In order to quantify this joint perturbation trend, the following tensor unit expression can be constructed to represent the perturbation intensity of an element in a three-dimensional tensor: , where E is the perturbation value of the tensor unit at the current moment (dimensionless); is the attitude angle change rate (e.g., roll angle change rate), indicating the terminal rollover intensity; is the gradient amplitude of the geomagnetic vector in the time window, indicating the degree of spatial magnetic field disturbance; is the acceleration modulus (e.g., multiple of gravity acceleration); To construct the disturbance stimulus response using an exponential decay function, the larger the acceleration, the closer the denominator is to 1, thereby amplifying the overall output of the above formula;

[0076] In the above expression, the acceleration modulus is The larger the value, the more strenuous the exercise. The smaller the value, the closer the denominator is to 1, thus increasing the overall disturbance value. If the attitude angle changes drastically at the same time ( increase) and magnetic field mutation ( Increase), the entire disturbance tensor element value E will rise rapidly; once multiple tensor elements E collectively rise in the same time window, it can be determined that the communication environment may have entered a "high risk, severe channel disturbance" state.

[0077] The goal of generating tensors is not just for visualization analysis, but to extract extreme points in the structure as a sensitivity indicator for potential interference in the communication state at this moment.

[0078] The generation logic of the communication reachability score is:

[0079] After completing the construction of the environment normalized feature vector and the disturbance structure tensor, these two types of data need to be fused and mapped into a communication link reachability indicator space;

[0080] Each component in the standardized environmental eigenvector is individually mapped. The core idea of this mapping function is to introduce a corresponding response adjustment factor (called the excitation coefficient) for each sensor eigenvalue. This response adjustment factor is used to control the response amplitude of the feature to the final scoring result. The mapping method adopts the form of a hyperbolic tangent function with a saturation interval. By adjusting the steepness of the response curve, the eigenvalue has a stable response capability to the scoring system.

[0081] The perturbation extreme value in the perturbation structure tensor is extracted as the global perturbation term. By combining it with the above-mentioned sensor eigenvalue term, the total input value of the scoring function is constructed. This combination adopts a splicing mechanism based on extreme value extraction and suppression function, in which the perturbation extreme value is input as the perturbation sensitivity factor to dominate the low value interval of the scoring function.

[0082] Finally, the combined result is input into a nonlinear boundary-preserving function. This function aims to compress and map the linear superposition result to the interval [0, 1] while maintaining the response continuity at the boundary. Non-sigmoid activation methods such as SoftSign function or Swish function can be used. The output result is the communication reachability score factor. The closer the score factor is to 1, the more stable the current communication environment and the more controllable the channel quality. The closer it is to 0, the greater the risk to the communication link.

[0083] A time-series sliding window mechanism is introduced: a fixed-length score record window is maintained within the terminal. Each time a new communication reachability score is received, the difference between it and the communication reachability score at the previous moment in the window is calculated. If the current score drops by more than the set drop threshold, a communication mutation flag is generated, indicating a communication environment mutation behavior.

[0084] It should be noted that the threshold is set based on empirical tolerance for environmental drift, typically between 0.1 and 0.2. Large changes in the score indicate a dramatic change in the environment, such as entering a tunnel, an elevator car closing, or a cliff face. In these cases, switching to the Beidou short message channel in advance can significantly improve link stability and the timeliness of alarm transmission.

[0085] After completing multi-source perception and fusion modeling of the communication environment, it is necessary to further determine the primary and backup paths of the communication channel based on the environmental perception results and link status estimation results. This allows the system to automatically switch to the Beidou short message channel when the 4G public network signal quality degrades or becomes unavailable, ensuring the most basic two-way short message communication function. After the 4G network is restored, it is necessary to quickly determine whether to switch back to the public network channel to support large-scale data transmission tasks such as image summaries and remote scheduling commands. To avoid resource loss and communication interruptions caused by frequent switching, an asymmetric hysteresis mechanism is adopted. Based on the two core indicators of perception score and 4G link activity score, a structured decision rule is established.

[0086] Step 2: Check the link status and switch between the primary and backup communication channels. The details are as follows:

[0087] Construct a joint communication status judgment indicator system:

[0088] The communication accessibility score generated in step 1 is used as the primary environmental factor for channel switching. This score integrates multiple environmental factors, such as air pressure disturbances, attitude changes, magnetic field disturbances, and acceleration fluctuations, to provide an integrated assessment of whether the current environment is suitable for establishing a stable communication link. The closer this score is to 1, the more stable the environment, with less channel interference, and suitable for maintaining high-speed communication. Conversely, a lower score indicates a degraded communication environment, requiring consideration of downgrade strategies or activation of backup channels.

[0089] In addition to environmental factors, a 4G link activity scoring factor is introduced as a communication state vector, that is, a dynamic evaluation function that includes signal stability and position disturbance trend is constructed. Specifically, the 4G link activity score is used to characterize the dynamic communication state of the current public network link, and comprehensively reflect the fluctuation trend and potential degradation risk of the communication link. This indicator does not rely on the received signal strength or signal interference ratio at a single time point, but is constructed based on the 4G received power change rate and the terminal's geographical location disturbance amplitude within a certain time window. Specifically, first, the changes in the 4G signal strength received by the terminal are continuously recorded within a given monitoring period, and the rate of decrease of the received power per unit time is calculated; at the same time, based on the continuous position point sequence provided by the terminal positioning module (such as BDS / GPS), the spatial displacement amplitude within the same period is calculated to quantify the position disturbance trend of the terminal in the physical space;

[0090] In order to integrate the dynamic change characteristics of the above two dimensions, a weighted combination structure is introduced to construct a 4G link activity scoring function, in which signal stability reflects the fluctuation of the signal level, and the position disturbance trend reflects the risk of link degradation caused by environmental occlusion or geographical distance. This function adopts a linear coupling structure, which allows the influence of signal and position on the 4G link activity score to be adjusted separately, so as to adapt to the sensitivity requirements in different application scenarios. For example, if the power drop rate is significant and the terminal displacement quickly approaches a known occlusion area (such as a canyon or tunnel entrance), the 4G link activity score will rise rapidly, indicating that the current link is in a high degradation risk state; for example, the 4G link activity scoring function is calculated as follows: ,in, This is a 4G link activity score used to characterize link degradation trends. A larger value indicates a more unstable link. The change in 4G received power per unit time is usually a negative value (indicating signal attenuation). Its absolute value represents the rate of decrease. is the monitoring period length in seconds; The spatial movement distance of the terminal during the monitoring period can be obtained by calculating the Euclidean distance or path integral of the start and end GPS coordinates;

[0091] The calculation of the 4G link activity score aims to dynamically perceive the immediate stability and failure risk of public network communication links. As a key input parameter for determining the primary and backup channel switching, compared with traditional assessment methods based on instantaneous signal strength, this method effectively improves the foresight and stability of link status judgment by introducing two dynamic dimensions: signal trend and location change. Especially in inspection scenarios with intermittent coverage, high mobility, or complex environments, this processing mechanism can significantly enhance the real-time responsiveness of communication switching strategies and the accuracy of link selection.

[0092] The communication reachability score and the 4G link activity score are combined to form a link state vector, where the first component reflects the physical feasibility of the environment for the link, and the second component reflects the signal behavior stability of the network itself.

[0093] Set the segmented hysteresis switching strategy:

[0094] Based on the aforementioned dual-factor link state vector, an asymmetric threshold judgment model was constructed to reduce frequent channel switching caused by signal fluctuations. This model divides the communication reachability score into three intervals: high reachability, switching hysteresis, and low reachability. The high reachability indicates a smooth environment with a stable 4G signal, prioritizing the use of 4G channels. The low reachability indicates a complex environment with degraded public network quality, requiring active switching to the Beidou short message link. The switching hysteresis in the middle is used to maintain the current communication state unchanged to avoid repeated switching caused by small fluctuations.

[0095] The specific values are as follows: A communication accessibility score exceeding 0.8 is considered high accessibility, maintaining the current 4G primary link; a score below 0.5 is considered low accessibility, triggering a channel switching strategy to switch to the Beidou short message link; a score between 0.8 and 0.5 is considered a hysteresis switch state, with no immediate switch and a monitoring buffer period. The 4G link activity score is used as a secondary basis for judgment. If this value shows a negative growth trend, meaning signal strength decreases per unit time and the terminal moves significantly, indicating a strong signal degradation trend, the channel switching strategy can be triggered, even if the communication score does not fall below 0.5, to switch to the Beidou short message link backup channel in advance.

[0096] After switching the main channel to the backup channel, the structure of the current communication task needs to be adapted and adjusted. Because Beidou short messages have a strict byte limit of about 120 characters in a single transmission, they cannot carry large-capacity task packages such as redundant data, image summaries, and inspection logs.

[0097] Build a communication task structure mapping mechanism to classify the current pending tasks according to priority, including:

[0098] Category 1 tasks: Short-content tasks such as personnel positioning, fault alarm, and emergency assistance are sent preferentially through the Beidou short message channel;

[0099] Category 2 tasks: such as device status change records and log data summaries, sent via 4G links;

[0100] The third type of tasks, such as image transmission and operation record upload, require a file transmission channel supported by a 4G link. If the Beidou short message link is switched, the data will be temporarily cached.

[0101] When switching to the Beidou link, only the necessary fields in one type of task are extracted to form a streamlined structure, including the terminal number, longitude and latitude position, alarm type identifier, timestamp and scene feature code, to avoid exceeding the short message capacity limit.

[0102] In summary, link status assessment and primary / backup channel switching are the core processes for achieving robust communication assurance in complex real-world environments. By building an environment-driven scoring mechanism and a network link dynamic response model, combined with an asymmetric hysteresis strategy, an intelligent downgrade switching from 4G to Beidou and an automatic recovery mechanism to the public network are implemented, ensuring reliable minimum communication capabilities even in extreme operating scenarios.

[0103] Step 3: Communication task identification and priority scheduling. Based on the current communication channel capabilities (such as 4G public network or Beidou short message) and the communication reachability score, task identification, priority classification, and scheduling queue management are performed. The specific contents are as follows:

[0104] Perform communication task structure analysis and task attribute vector extraction:

[0105] The first step in communication task identification is a structural analysis of the task. Each task, when generated, contains not only its original content but also related task metadata. For unified processing, the task structure needs to be abstracted into multiple attribute vectors. These typically include: task generation time, maximum delay time, data size, task urgency, and link reachability score (i.e., whether transmission on the BeiDou short message channel is permitted).

[0106] These attribute vectors do not directly participate in scheduling, but serve as input factors in the subsequent calculation of the priority scoring function. Attribute vectors interact with each other. For example, a task with large data volume but high urgency may still require priority scheduling in a bandwidth-constrained channel.

[0107] The construction and calculation logic of the priority scoring function include:

[0108] After the task attribute vectors are constructed, a nonlinear priority scoring function needs to be established to implement task scheduling and sorting. This function is used to convert the multi-attribute vector inputs into comparable scoring values. The priority scoring function must meet the following technical requirements:

[0109] For emergency tasks (such as warnings and rescue positioning), the system should have exponential response capabilities, ensuring that the score is significantly higher than that of ordinary tasks.

[0110] For overdue tasks or tasks with low delay tolerance, the priority score function should decrease rapidly;

[0111] Considering the time interval between task generation and the current time, if the time is too long and the task has not been transmitted, the priority scoring function will be gradually increased to prevent long-term backlog;

[0112] The priority scoring function is used to quantify the scheduling value of each task under the current communication status. It is calculated by jointly modeling the task attributes and the network status. Specifically, the urgency, generation time, maximum delay time, and communication reachability score of each task to be scheduled are first extracted. The urgency of the task is used as a static scheduling factor to reflect the priority level of the task; the task generation time is used to construct the time decay term to evaluate the time sensitivity of the task at the current moment; the task delay tolerance and the link reachability score together constitute the transmission feasibility term, which is used to evaluate whether the task has reasonable transmission conditions under the current link.

[0113] To better reflect the immediate scheduling value of a task, a nonlinear function is used to construct a time modulation term. This term uses the difference between the task generation time and the current system time as input, multiplied by a tuning parameter, and used as the variable of an exponential function to generate a time effect score for the task. This approach simulates the sharp increase in scheduling pressure when a task is approaching timeout, overcoming the insensitivity of the linear time decay model.

[0114] At the same time, to evaluate the task's transmittability under link conditions, the task's maximum allowable delay time is multiplied by the link reachability score. The result is input into a nonlinear response function and mapped into a transmittability score. This score establishes a dynamic mapping relationship between the task's own time constraints and the current link status, which can effectively reflect whether the task is suitable for current transmission.

[0115] Finally, the time effect score and the transmission feasibility score are structurally combined, and the normalized score value is outputted through a boundary compression function, limited to between 0 and 1. This compression function uses the input value divided by its absolute value plus 1. It has good boundary continuity and intermediate value resolution capabilities, can preserve score details, and avoid distortion caused by extreme values in the ranking.

[0116] For example, a specific example expression combining the structure of the priority scoring function and the boundary compression processing method is: , where PF represents the final normalized priority score, with a value range of (-1, 1). If it needs to be limited to [0, 1], it can be further linearly mapped; SJ is the time effect score item of the task, which indicates the urgency of the task; CS is the transmission feasibility score item of the task, which is obtained by multiplying the delay tolerance and the link reachability score.

[0117] Perform scheduling window construction and subset generation:

[0118] The scheduling window and subset generation mechanism is used to screen the task set with the highest current priority score and the best adaptability to the link state under the condition of limited communication resources, ensuring the rapid scheduling and transmission of high-priority tasks within the established transmission capacity range. The task scheduling subset is constructed based on the task priority score results and the communication channel transmission capacity indicator, forming the minimum task combination that can be executed within the current scheduling cycle.

[0119] First, the available transmission capacity threshold for the current scheduling period is set based on the primary communication channel type (e.g., 4G public network or BeiDou short message). This threshold serves as the upper bound of the scheduling window, reflecting the total amount of data that can be transmitted per unit time under the current link conditions. For 4G links, this capacity is determined based on real-time bandwidth assessment results, while for BeiDou short message links, it is a fixed maximum message length, such as 120 bytes. This transmission capacity, denoted as RL, serves as an upper bound for subsequent task subset screening.

[0120] Specifically, the bandwidth capability identifier of the current communication channel (which can be an estimated 4G network rate or the maximum load of a Beidou short message) and the scheduling cycle length (for example, the maximum transmission time available for the current communication scheduling) are multiplied to obtain a practically allocable communication budget as the transmission capacity.

[0121] The calculated task priority scores are sorted in descending order to form a task queue. The highest-scoring tasks are selected from the head of the queue and their data volumes are accumulated until the total volume is about to exceed the current window capacity. Task selection is stopped, forming a task subset for the current scheduling cycle. This subset, denoted as Ts, is the optimal task set that satisfies both the scoring priority and transmission capacity constraints.

[0122] Perform communication channel adaptation and task structure mapping:

[0123] The communication channel adaptation and task structure mapping mechanism is used to dynamically adjust the task data structure format based on the capabilities of the current primary communication link, ensuring that the scheduled task subset is executable and efficient during the actual transmission process. Due to significant differences in transmission rate, maximum data packet capacity, and continuity assurance between 4G links and Beidou short message links, task structures need to be differentiated to meet the transmission requirements of different links.

[0124] Specifically, the current primary communication channel type is first identified. If it is a 4G public network link, it can support the transmission of task packages in a standard structure format, including multi-field data structures such as image summaries, job logs, positioning trajectories, and multi-parameter status quantities. No compression mapping is required, and the task can be directly packaged in its original structure and submitted to the communication interface.

[0125] If the current main channel is the Beidou short message link, it is limited by the maximum byte limit of each message sent (for example, within 120 bytes), and the scheduling task must be structure compressed and field filtered. The task structure mapping process is as follows:

[0126] Perform field screening and reconstruction to retain the necessary fields in the task, including the terminal unique identifier, latitude and longitude coordinates, task number, event type code, timestamp, and several status bit flags. Non-critical fields (such as image summary, complete log, auxiliary status variables, etc.) are eliminated;

[0127] Perform field encoding compression and convert the task fields into compact encoding. For example, fixed-length encoding, predefined index mapping, or bit mask structure are used to compress fields such as task type, status label, and alarm level into integer or binary bit strings.

[0128] Perform field alignment and byte control, byte-align all reserved fields, and ensure that the total length of the structure is within the available link length range. If the limit is exceeded, perform differential compression on the position information or split the task into multiple short messages for asynchronous transmission.

[0129] To ensure the effectiveness of tasks after structural mapping, a task structure adaptation template library is built. The appropriate structure compression template is automatically selected based on different link types. The template is bound to each task in the scheduling subset before scheduling, ensuring that the task has completed structural adjustment before transmission, avoiding message truncation or communication failure due to structure mismatch.

[0130] In addition, the task structure mapping can also be used to design a fragment reassembly mechanism in the short message link. When the task needs to be split into multiple short message fragments for transmission, a task identifier and serial number index are attached to each fragment. The receiving end reassembles and restores the fields in sequence to ensure the logical integrity and business consistency of the task content.

[0131] Continuously monitor the terminal's operating status and environmental disturbance status, build an emergency status identification model and short message active triggering strategy, and ensure closed-loop communication goals of sending, receiving, and feedback of information even when there is no public network coverage;

[0132] Step 4: Build an emergency trigger and short message rapid response mechanism. The specific steps are as follows:

[0133] Preprocesses multiple sensor input data types (such as acceleration, air pressure, gyroscope angular velocity, geomagnetic disturbances, and distance changes) from the terminal. Multiple anomaly detection factors are constructed for different risk scenarios, such as those indicating falls, prolonged inactivity, spatial vibration intensity, and sudden changes in air pressure. A combination of high-order derivatives of continuous time series, disturbance gradients, and trend amplitudes is used to enhance sensitivity to sudden events.

[0134] Taking the drop factor as an example, rather than directly determining whether the acceleration exceeds a threshold, the deviation between the instantaneous growth rate of the acceleration modulus and the integral of the amplitude change per unit time is calculated. If this deviation accumulates rapidly and exceeds a set change threshold, it is marked as a potential drop behavior. The construction of the stationary time factor does not use average acceleration. Instead, it determines the stable state based on whether the rate of change of acceleration at multiple moments approaches zero and continuously exceeds the time threshold.

[0135] Construct and process the nonlinear combination risk scoring function of multiple anomaly detection factors:

[0136] The nonlinear combination risk scoring function of multiple anomaly detection factors is used to assess the potential abnormal state level of the terminal in the current environment. It achieves a quantitative analysis of the overall risk by integrating key indicators from multiple sensor data. Specifically, several independent anomaly detection factors are first defined. Each anomaly detection factor represents the response intensity of a certain type of sensor abnormal event, such as acceleration mutation, attitude flip rate, geomagnetic disturbance gradient, and sudden drop in air pressure. To achieve unified dimensional processing, all anomaly detection factors are first normalized to ensure that their values are within a consistent standard range.

[0137] A nonlinear amplification mechanism is introduced to process the normalization factors. Specifically, each normalized anomaly detection factor is passed as an input variable into a modulation function with a saturation response characteristic, such as the hyperbolic tangent function (tanh). This type of function has a smooth output change when the input value is small, which can suppress false signals caused by slight disturbances. However, when the input value approaches the abnormal critical region, the output response rises rapidly, achieving strong amplification of the sudden event and forming a nonlinear gain structure.

[0138] All factor output values after nonlinear amplification are combined and aggregated through exponential mapping. For example, each amplification value is first raised to the power of its corresponding sensitivity index, and then all results are accumulated. Finally, the overall risk score result is constructed by taking the maximum power index value as the normalization factor. This structure emphasizes the scoring logic of strong anomalies leading and weak anomalies cooperating, ensuring that the total score rises rapidly when one or more key factors are significantly abnormal. At the same time, when multiple medium-intensity factors are acting simultaneously, the risk score can also be effectively accumulated.

[0139] For example, suppose the set of anomaly detection factors is: , represents the kth anomaly detection factor, and the risk score function is defined as follows: ,in, is the i-th anomaly detection factor (normalized); is the sensitivity amplification value of the i-th anomaly detection factor, which adjusts the steepness of its contribution to the overall risk and is set according to actual needs; is the sensitivity index;

[0140] For example, under the condition of existing data accumulation, by analyzing the historical real risk events (such as falls, slips, and static coma) and the response intensity change trend of each abnormal detection factor before the event, the average advance rise amplitude and peak response ratio of each type of factor before the risk appears can be calculated. The sensitivity index can be defined as: ,in, is the average value of the i-th anomaly detection factor before the risk event; The average value of the anomaly detection factor during the non-risk period; It is an empirical adjustment factor that controls the overall magnification and is set according to the actual scenario; A small constant to prevent the denominator from being zero.

[0141] The construction of a multi-factor nonlinear combined risk scoring function aims to dynamically perceive the coupling effect between terminal status and external environmental disturbances, providing a quantifiable, adjustable, and interpretable risk level output indicator. This function avoids over-reliance on a single anomaly detection factor and reduces the probability of false triggering of risk assessments due to occasional disturbances. The introduction of a nonlinear response function enhances the score's ability to detect sudden changes, while the maximum exponent normalization strategy ensures the stability of the score boundaries.

[0142] Construct risk trend windows at multiple time scales:

[0143] Based on time, the system divides risk evolution into three levels: short-term, medium-term, and long-term. These levels correspond to the ability to perceive risk changes at the second, ten-second, and minute levels, respectively. It can simultaneously identify different risk patterns: those that are highly sudden, those that are medium-term, or those that evolve slowly.

[0144] In terms of specific implementation, three time windows are set: the short time window is used to capture sudden, high-intensity risks, such as terminal drops and violent collisions; the medium time window focuses on changing trends at the level of tens of seconds, such as short-term inactivity of personnel in special conditions, abnormal posture, or magnetic field interference; and the long time window focuses on the cumulative state of risk scores within a few minutes. It is mainly used to identify low-frequency risks that evolve slowly but may be potentially harmful, such as loss of mobility, prolonged inactivity, or sustained air pressure drop.

[0145] Within each time window, we continuously track changes in the risk score over time and accumulate the risk score over the entire time period covered by the window. This accumulation process does not only focus on the score's instantaneous value, but also considers the duration of its high level. Simply put, if the risk score remains at a medium-high level for a period of time, even if it does not reach its peak, it will be considered threatening due to its persistence.

[0146] To determine whether the accumulated risk has reached the emergency triggering standard, a risk threshold is set for each time window. This threshold represents the risk score that is considered sufficient to trigger an actual security incident within that time scale. If the cumulative value of the risk score within the window exceeds the corresponding set threshold, it is considered that there is continuous risk behavior in that time period.

[0147] A dual judgment mechanism is implemented. A terminal is considered to be in a high-confidence abnormal state only when the cumulative risk scores of at least two of the three time windows simultaneously exceed their respective risk thresholds. This dual-window collaborative triggering strategy can filter out short-term, sporadic disturbances and avoid false reports caused by sensor noise or transient anomalies. It also ensures a timely response to truly dangerous events. In particular, when risks manifest simultaneously on two time scales, they indicate sufficient intensity and persistence, and the emergency response process should be triggered first.

[0148] Furthermore, the mechanism supports setting differentiated window lengths and judgment thresholds according to different usage scenarios. For example, for high-intensity work sites, a shorter window response time and a lower judgment threshold can be set to achieve rapid perception of severe falls or impacts; for long-term stationing environments, the threshold of the short-term window can be increased and the trigger threshold of the long-term window can be lowered to enhance the monitoring capability of slow-onset risks.

[0149] When the current terminal is determined to be in a high-risk state through the aforementioned risk scoring point judgment mechanism and the triggering conditions are confirmed to be met, the emergency short message construction process will be immediately started to generate the minimum structured communication data content and initiate a high-priority emergency sending request through the Beidou short message channel.

[0150] Construct and send the emergency short message structure:

[0151] In terms of message content design, the system adopts the principle of field minimization, retaining only core fields to ensure that the total data length is within the Beidou short message communication capability (for example, no more than 120 bytes). The field structure is sorted according to the practical priority of emergency response, including but not limited to the following elements:

[0152] Terminal identity field: used to uniquely identify the device or person currently initiating emergency communication, which can be a device ID or registration code;

[0153] Location information field: includes longitude, latitude, and optional altitude information, providing geographic positioning basis;

[0154] Risk type field: Output by the system risk assessment module, using preset codes to represent types such as falling, instability, stationary, and abnormal air pressure;

[0155] Risk level field: represents the risk score level in the current state, divided into several risk level labels (such as low, medium, high, and very high);

[0156] Timestamp field: records the sending time to ensure that the receiver has a clear understanding of the timing of events;

[0157] Status summary field: used to encode several sensor abnormality flags, such as whether there is magnetic disturbance, attitude flip, stationary timeout, etc., to support remote preliminary judgment analysis;

[0158] In terms of the sending strategy of emergency short messages, it can be set to have immediate sending priority without waiting in line for the task scheduling window. At the same time, in order to ensure the accessibility of emergency information, the system will enter the retransmission guarantee process after the first transmission. The specific method is: if the reception confirmation or response feedback is not received from the scheduling end within the set time, the system will repeatedly send the same short message at the set time interval, and record the time point and sending status of each sending behavior. The number of retransmissions is set to a limited number, such as three or five times. After exceeding the number, the terminal enters the standby listening state, waiting for other links to recover or manual access intervention;

[0159] In addition, in order to improve the information processing efficiency at the receiving end, all emergency short messages can be structurally equipped with a unified emergency identification header to facilitate the Beidou receiving system or scheduling platform to quickly analyze, classify, store and prioritize them. For multiple consecutive risk events, the most recent risk score trigger point will be used as the benchmark to prevent the accumulation of duplicate messages or information redundancy caused by repeated fluctuations in risk scores in a short period of time.

[0160] It should be noted that the relevant threshold information in this embodiment is pre-set by professionals and will not be explained in detail here. Some parameter English letters in the embodiments have the same situation, but different meanings are explained when used, and will not be explained one by one here.

[0161] The present invention realizes real-time quantitative assessment of the accessibility of the communication environment through multi-source environmental perception and link status fusion modeling, can dynamically judge the stability and effectiveness of the public network link, and provide data support for the switching of communication channels. Secondly, the scheduling scoring model constructed based on link status and task characteristics enables the terminal to give priority to transmitting high-urgency and high-adaptability tasks under link-restricted conditions, avoid low-value tasks from occupying key communication resources, and improve the efficiency of communication resource utilization. In addition, by introducing a multi-time scale risk integration mechanism, the recognition accuracy of sudden states such as falling, stillness, and sudden changes in air pressure is improved, and structured emergency short messages can be automatically generated without human intervention, ensuring that SOS information can be quickly uploaded and the location is returned when the public network is interrupted or personnel lose contact, thereby improving the stability, security and engineering adaptability of two-way communication in network-free scenarios.

[0162] The above formulas are all dimensionless and numerical calculations. The formulas are obtained by collecting a large amount of data and performing software simulation to obtain the most recent real situation. The preset parameters in the formulas are set by technicians in this field according to actual conditions.

[0163] The above embodiments may be implemented in whole or in part through software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments may be implemented in whole or in part in the form of a computer program product.

[0164] Those skilled in the art will appreciate that the modules and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0165] In addition, each functional module in each embodiment of the present application may be integrated into one processing module, or each module may exist physically separately, or two or more modules may be integrated into one module.

[0166] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

[0167] Finally: 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 in the scope of protection of the present invention.

Claims

1. A two-way short message communication method for a non-network scenario, characterized by: The steps include: Based on the multi-source sensor data integrated by the terminal, a disturbance tensor structure is constructed, and a communication reachability score is generated through nonlinear mapping. Combined with the sliding window, sudden changes in the communication environment are detected. A communication state vector is constructed based on the 4G link activity score factor. Based on the combined judgment of the communication reachability score and the 4G link activity score, an asymmetric hysteresis switching strategy is implemented to complete the primary and backup channel switching between the public network communication channel and the Beidou short message channel. Extract attribute vectors from scheduled tasks, construct a nonlinear priority scoring function, generate task scheduling subsets under communication resource constraints, and perform structure mapping and format compression processing based on the main channel type to form transmission task packages that can adapt to the link; Continuously monitor risk factors and perform risk scoring, combine multi-time scale integration windows to analyze risk trends and determine high-confidence abnormal states. Once a high-confidence abnormal state is confirmed, a minimum-structured emergency short message is generated and sent preferentially through the Beidou link.

2. A two-way short message communication method for a non-network scenario according to claim 1, characterized in that: Based on the multi-source sensor data integrated by the terminal, a disturbance tensor structure is constructed. The specific steps include: The sensor modules integrated into the terminal collect on-site environmental information. The sensors used include air pressure sensor, three-axis accelerometer, geomagnetic sensor, gyroscope, light sensor, infrared or ultrasonic ranging sensor; The sensor data output by each type of sensor is mapped to a unified scale to obtain the environmental standardized feature vector; When the terminal moves, rotates rapidly, or experiences abnormal magnetic disturbances in its spatial orientation, the acceleration modulus is used as a disturbance factor. The gradient change of the geomagnetic vector is used to represent the intensity of the magnetic space disturbance. Combined with the attitude angle change, a three-dimensional cross-mapping is formed to construct a three-dimensional disturbance tensor structure to capture the joint disturbance trend. In the three-dimensional perturbation tensor structure, the value of each element is determined by a nonlinear combination of three types of perturbation factors. The acceleration factor is placed in the denominator as a perturbation excitation term, and the mutation behavior is enhanced by an exponential function. The attitude angle change and the magnetic space perturbation intensity term are placed in the numerator as weight control terms.

3. A two-way short message communication method for a non-network scenario according to claim 2, characterized in that: The communication reachability score is generated through nonlinear mapping, and the sudden change behavior of the communication environment is detected by combining the sliding window. The specific steps include: After completing the construction of the environment normalized feature vector and the disturbance structure tensor, these two types of data are fused and mapped into a communication link reachability indicator space; For each sensor eigenvalue, a corresponding response adjustment factor is introduced and mapped using the hyperbolic tangent function of the saturation interval; The extreme value of the disturbance in the disturbance structure tensor is extracted and used as the global disturbance term. By combining it with the sensor eigenvalue term, the total input value of the scoring function is constructed. The extreme value of disturbance is input as the disturbance sensitivity factor, dominating the low value interval of the scoring function; The combined result is input into a nonlinear boundary-preserving function, the linear superposition result is compressed and mapped into the interval [0, 1], and the communication reachability score factor is output; A fixed-length scoring record window is maintained inside the terminal using a sequential sliding window mechanism. Every time a new communication reachability score is received, the difference between it and the communication reachability score result at the previous moment in the window is calculated. If the current score drops by more than the set drop threshold, a communication mutation flag is generated and used as a communication environment mutation behavior.

4. The method for two-way short message communication in a non-network scenario according to claim 3, wherein: A communication state vector is constructed based on the 4G link activity score factor. Based on the combined judgment result of the communication reachability score and the 4G link activity score, an asymmetric hysteresis switching strategy is implemented. The specific steps include: The communication reachability score is used as an environmental factor for channel switching, and the 4G link activity score factor is introduced as a communication state vector to evaluate signal stability and location disturbance trends. The 4G link activity score represents the dynamic communication status of the current public network link. The signal stability of the 4G link activity score is determined by continuously recording the changes in the 4G signal strength received by the terminal within a given monitoring period and calculating the rate of decrease in received power per unit time. Based on the continuous position point sequence of the terminal positioning module, the spatial displacement amplitude within the same period is calculated to determine the position disturbance trend of the terminal in physical space. A weighted combination structure is then used to construct the 4G link activity score function. The communication reachability score and the 4G link activity score are combined to form the link state vector. The communication reachability score reflects the physical feasibility of the environment for the link, while the 4G link activity score reflects the stability of the signal behavior of the network itself. A segmented hysteresis switching strategy is set according to the link state vector.

5. The two-way short message communication method for a non-network scenario according to claim 4, characterized in that: The switching between the public network communication channel and the Beidou short message channel is completed, including the following steps: When the communication accessibility score exceeds 0.8, it is determined to be in a high reachability state and the current 4G main link communication is maintained; when the communication accessibility score is lower than 0.5, it is determined to be in a low reachability state and the channel switching strategy is triggered to switch to the Beidou short message link; when the communication accessibility score is less than or equal to 0.8 and greater than or equal to 0.5, it is in a switching hysteresis state and does not switch immediately, entering the monitoring buffer period; The 4G link activity score is used as an auxiliary judgment basis. If the 4G link activity score shows a negative growth trend, the channel switching strategy is triggered and the backup channel is switched in advance. After switching to the backup channel, the structure of the current communication task is adapted and adjusted; Build a communication task structure mapping mechanism to classify the currently pending tasks into first-class tasks, second-class tasks, and third-class tasks according to their priorities; When switching to the Beidou link, the necessary fields in a type of task are extracted to form a structure. The necessary fields include terminal number, longitude and latitude position, alarm type identifier, timestamp and scene feature code to avoid exceeding the short message capacity limit.

6. The two-way short message communication method for a non-network scenario according to claim 5, characterized in that: Extracting attribute vectors for scheduling tasks and constructing nonlinear priority scoring functions include the following steps: The task structure is abstracted into an attribute vector, which includes task generation time, maximum delay time, data volume, task urgency, and link reachability score; After the task attribute vector is constructed, the task scheduling is sorted and a nonlinear priority scoring function is constructed; The priority scoring function is used to quantify the scheduling value of each task under the current communication state, and is calculated by jointly modeling the task attributes and the network state; Extract the urgency, generation time, maximum delay time, and communication reachability score of each task to be scheduled; A nonlinear function is used to construct a time modulation term. The difference between the task generation time and the current system time is used as input, multiplied by the adjustment parameter and used as the variable of the exponential function to generate the time effect score of the task. Evaluate the task's transmittability under link conditions by multiplying the task's maximum allowable delay time by the link reachability score. The result is input into a nonlinear response function and mapped into a transmittability score. The transmittability score reflects whether the task is currently transmitted. The time effect score and the transmission feasibility score are structurally combined, and the normalized score value is output as the priority score through the boundary compression function, which is limited between 0 and 1.

7. The two-way short message communication method for a non-network scenario according to claim 6, characterized in that: Generate a task scheduling subset under the communication resource constraints, and perform structure mapping and format compression processing according to the main channel type to form a transmission task package that can adapt to the link. The following steps are included: The available transmission capacity threshold for the current scheduling period is set based on the primary communication channel type. The available transmission capacity threshold is the upper bound of the scheduling window, reflecting the total amount of data that can be transmitted per unit time under the current link conditions. For 4G links, the available transmission capacity threshold can be determined based on real-time bandwidth assessment results. For Beidou short message links, the available transmission capacity threshold is a fixed maximum message length. The bandwidth capability identifier of the current communication channel and the scheduling cycle time length are multiplied to obtain the allocable communication budget as the transmission capacity; The bandwidth capability identifier is the estimated value of the 4G network rate or the maximum load of the Beidou short message, and the scheduling cycle time length is the maximum transmission time available for the current communication scheduling; Sort the calculated task priority scores in descending order to form a task scheduling queue. Select the task with the highest score from the head of the queue in turn, and accumulate the data volume until the total amount exceeds the current window capacity limit. Then stop task selection and form a subset of the current scheduling cycle as the task scheduling subset. Identify the current primary communication channel type to form an adaptable link transmission task packet. If it is a 4G public network link, no compression mapping processing is required; If the current main channel is the Beidou short message link, the scheduling task performs structure compression and field reduction processing to form a transmission task package. The field reduction processing includes field screening and reconstruction, field coding compression, field alignment and byte control.

8. The two-way short message communication method for a non-network scenario according to claim 7, characterized in that: Continuously monitor risk factors and perform risk scoring, and combine multi-time scale integration windows to analyze risk trends and determine high-confidence abnormal states, including the following steps: Construct anomaly detection factors for different risk scenarios, and construct and process nonlinear combination risk scoring functions for the anomaly detection factors. The risk scoring function is used to assess the potential abnormal state level of the terminal in the current environment. All anomaly detection factors are first normalized and nonlinearly amplified using the hyperbolic tangent function. The output values of all factors after nonlinear amplification are combined and aggregated through exponential mapping to obtain a risk score. Based on time, three time windows are set, which correspond to time window lengths of seconds, ten seconds, and minutes respectively; In each time window, the risk score is accumulated over the entire time period covered by the window, and a risk threshold is set for each time window to conduct continuous risk behavior detection; If the cumulative risk scores of at least two of the three time windows exceed the respective set risk thresholds at the same time, it is determined that the current terminal is in a high-confidence abnormal state.

9. The two-way short message communication method for a non-network scenario according to claim 8, characterized in that: When a high-reliability abnormal state is confirmed, a minimum-structured emergency short message is generated and sent preferentially through the BeiDou link, including the following steps: When the high-confidence abnormal state triggering conditions are met, the emergency short message construction process is immediately started to generate the minimum structured communication data content, and a high-priority emergency sending request is initiated through the Beidou short message channel.

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