Communication link switching method and related device

Abstract

The invention discloses a communication link switching method and a related device, channel quality is calculated by adopting multiple channel quality indexes of links, the problem of wrong switching caused by fluctuation of a single index can be effectively avoided, a link switching threshold value and a switching judgment period are updated according to the multiple channel quality indexes of each link in a preset time window, and the switching efficiency is improved. According to the method, the link switching threshold and the switching judgment period can adapt to signal fluctuation in a low-altitude complex environment, the error switching rate and the communication interruption risk are reduced, unnecessary frequent switching can be avoided, and resource consumption is reduced.

Description

Technical Field

[0001] This invention relates to a communication link switching method and related apparatus, belonging to the field of wireless communication technology. Background Technology

[0002] With the rapid development of electric vertical takeoff and landing (eVTOL) aircraft in urban air traffic, logistics and other fields, higher requirements are being placed on the reliability and real-time performance of their communication systems. To ensure flight safety and mission continuity, aircraft are typically equipped with various wireless communication modules, such as 4G and 1.4G communication modules, to achieve stable transmission of flight control data, system status and environmental awareness information.

[0003] For various communication links, there are currently two main types of communication link switching methods. One type uses a fixed threshold switching mechanism, which switches to a backup link when the quality of the primary link drops to a preset threshold. Although the fixed threshold mechanism is simple to implement, it cannot adapt to signal fluctuations in complex low-altitude environments (such as building obstruction and electromagnetic interference), resulting in a high false switching rate and an increased risk of communication interruption. The other type relies on a single signal indicator (such as RSSI) for switching judgment, which can easily lead to false switching due to fluctuations in a single indicator. Summary of the Invention

[0004] This invention provides a communication link switching method and related apparatus, which solves the problems disclosed in the background art.

[0005] According to one aspect of this application, a communication link switching method is provided, comprising: In response to the arrival of the handover judgment time at the current time, or the link quality of the main link at the current time being less than the link quality threshold of the main link, the link handover threshold and handover judgment period are updated according to the channel quality of the link at each time within the preset time window; wherein, the updated handover judgment period is used to determine the next handover judgment time; the end time of the preset time window is the current time; In response to the following: the link quality of the primary link and the backup link at the current time is not less than their respective link quality thresholds; the channel quality of the backup link at the current time is greater than the channel quality of the primary link at the current time; and the difference between the channel quality of the backup link and the primary link at the current time is greater than the updated link switching threshold; or in response to the following: the link quality of the primary link at the current time is less than the primary link's link quality threshold; and the link quality of the backup link at the current time is greater than the backup link's link quality threshold, the primary link at the current time is switched to the backup link, and the backup link at the current time is switched to the primary link. The link quality and channel quality of the primary link at time A are calculated based on various channel quality indicators of the primary link at time A; the link quality and channel quality of the backup link at time A are calculated based on various channel quality indicators of the backup link at time A.

[0006] Furthermore, the links include 1.4G links and 4G links; The formula for calculating the channel quality of a 1.4G link is: Q1=w11*f(RSSI-1)+w12*f(RSRP-1)+w13*f(SNR); In the formula, Q1 is the channel quality of the 1.4G link, w11, w12 and w13 are weighting coefficients, RSSI-1, RSRP-1 and SNR are the received signal strength, reference signal received power and signal-to-noise ratio of the 1.4G link, respectively, and f is a preprocessing function, which performs exponential weighted moving average smoothing on the channel quality index and normalization on the smoothed channel quality index. The formula for calculating the channel quality of a 4G link is: Q2=w21*f(RSSI-2)+w22*f(RSRP-2)+w23*f(SINR)+w24*f(RSRQ); In the formula, Q2 is the channel quality of the 4G link, w21, w22, w23 and w24 are weighting coefficients, and RSSI-2, RSRP-2, SINR and RSRQ are the received signal strength, reference signal received power, signal-to-noise ratio plus interference ratio and reference signal received quality of the 4G link, respectively. The formula for calculating the link quality of a 1.4G link is: Q3=w14*f(RSSI-1)+w15*f(RSRP-1)+w16*f(SNR); In the formula, Q3 represents the link quality of the 1.4G link, and w14, w15, and w16 are weighting coefficients; The formula for calculating the link quality of a 4G link is: Q4=w25*f(RSSI-2)+w26*f(RSRP-2)+w27*f(SINR)+w28*f(RSRQ); In the formula, Q4 represents the link quality of the 4G link, and w25, w26, w27, and w28 are weighting coefficients.

[0007] Furthermore, based on the channel quality of the link at each moment within the preset time window, the link handover threshold and handover judgment period are updated, including: Calculate the new link handover threshold and channel volatility based on the channel quality of the link at each moment within the preset time window; Replace the old link switching threshold with the new one; Based on the channel volatility, a new handover decision period is determined and replaced with the old handover decision period.

[0008] Furthermore, the new link handover threshold and channel volatility are calculated using the following formula: Threshold_dynamic=(Sum(X1,...,X N ) / N)+Offset; In the formula, Threshold_dynamic is the new link switching threshold, and X i Sum(X1,...,X) is the absolute value of the channel quality difference between the primary link and the backup link at time i within a preset time window, where 1 ≤ i ≤ N, N is the size of the preset time window, Offset is the offset coefficient, and Sum(X1,...,X) is the value of the channel quality difference between the primary link and the backup link at time i within a preset time window. N ) represents X1~X N The sum of; Fluctuation=Sum(|S2-S1|,...,|S N -S N-1 |) / (N-1); In the formula, Fluctuation is the channel volatility, S i To represent the channel quality of the main link at time i within a preset time window, Sum(|S2-S1|,...,|S N -S N-1 |) represents |S2-S1|~|S N -S N-1 The sum of |.

[0009] Furthermore, based on the channel volatility, a new handover decision period is determined, including: If the channel volatility is less than the first threshold, the new handover determination period is the first period. If the channel volatility is not less than the first threshold and is less than the second threshold, the new handover judgment period is the second period. If the channel volatility is not less than the second threshold, the new handover judgment period is the third period; wherein the third period is shorter than the second period, and the second period is shorter than the first period.

[0010] Furthermore, the method also includes: In response to the following conditions: the link quality of the primary link and the backup link at the current time is not less than their respective link quality thresholds, the channel quality of the backup link at the current time is greater than the channel quality of the primary link at the current time, and the difference between the channel quality of the backup link and the primary link at the current time is not greater than the updated link switching threshold; or in response to the following conditions: the link quality of the primary link and the backup link at the current time is not less than their respective link quality thresholds, and the channel quality of the backup link at the current time is not greater than the channel quality of the primary link at the current time; or in response to the following conditions: the link quality of the primary link at the current time is not less than the link quality threshold of the primary link, and the link quality of the backup link at the current time is less than the link quality threshold of the backup link, the primary link and the backup link remain unchanged. In response to the current link quality being less than the primary link quality threshold and the current backup link quality being less than or equal to the backup link quality threshold, the system controls the primary link and backup link to communicate concurrently. During concurrent communication, if the link quality of the primary link or backup link improves, the frequency of concurrent communication is gradually reduced, and communication is ultimately conducted via the primary link or backup link.

[0011] Furthermore, the method also includes: If, within a preset timeframe after a primary link and backup link switchover, no primary link and backup link switchover is performed under any circumstances, and no primary link and backup link switchover is detected that the link quality of the primary link is less than or equal to the primary link's link quality threshold, then a primary link and backup link switchover will not be performed under any circumstances.

[0012] According to another aspect of this application, a communication link switching device is provided, comprising: The update module, in response to the current time reaching the handover judgment time or the current time's main link link quality being less than the main link link quality threshold, updates the link handover threshold and handover judgment period based on the channel quality of the link at each time within a preset time window; wherein, the updated handover judgment period is used to determine the next handover judgment time; the cutoff time of the preset time window is the current time; The switching module, in response to the following conditions: the link quality of both the primary link and the backup link at the current time is not less than their respective link quality thresholds; the channel quality of the backup link at the current time is greater than the channel quality of the primary link at the current time; and the difference between the channel quality of the backup link and the primary link at the current time is greater than the updated link switching threshold; or in response to the following conditions: the link quality of the primary link at the current time is less than the primary link's link quality threshold; and the link quality of the backup link at the current time is greater than the backup link's link quality threshold, controls the primary link at the current time to switch to the backup link, and controls the backup link at the current time to switch to the primary link. The link quality and channel quality of the primary link at time A are calculated based on various channel quality indicators of the primary link at time A; the link quality and channel quality of the backup link at time A are calculated based on various channel quality indicators of the backup link at time A.

[0013] According to another aspect of this application, a computer-readable storage medium is provided that stores one or more programs, the one or more programs including instructions that, when executed by a computing device, cause the computing device to perform a communication link switching method.

[0014] According to another aspect of this application, a computer device is provided, including one or more processors and one or more memories, wherein one or more programs are stored in the one or more memories and configured to be executed by the one or more processors, and the one or more programs include instructions for performing a communication link switching method.

[0015] The beneficial effects achieved by this invention are as follows: This invention uses multiple channel quality indicators of the link to calculate channel quality, which can effectively avoid the problem of false handover caused by fluctuation of a single indicator. According to multiple channel quality indicators of each link within a preset time window, the link handover threshold and handover judgment period are updated, which can make the link handover threshold and handover judgment period adapt to signal fluctuations in complex low-altitude environments, reduce the false handover rate and the risk of communication interruption, and avoid unnecessary frequent handovers, thus reducing resource consumption. Attached Figure Description

[0016] Figure 1 A flowchart of a communication link switching method; Figure 2 This is a schematic diagram of the structure of a dual-mode communication system; Figure 3 This is a block diagram of a communication link switching device. Detailed Implementation

[0017] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit this application or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0018] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this application.

[0019] At the same time, it should be understood that, for ease of description, the dimensions of the various parts shown in the accompanying drawings are not drawn according to actual scale.

[0020] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0021] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0022] It should be noted that similar symbols and letters in the following figures represent similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0023] Furthermore, in the description of the embodiments of this application, the terms "first," "second," etc., are used only for distinguishing descriptions and should not be construed as indicating or implying relative importance. Therefore, features defined with "first" or "second" may explicitly or implicitly include one or more features.

[0024] To address the problems of existing communication link switching methods, this application proposes a novel method. This switching method can be executed by a switching device, which can be a control unit built into the aircraft, a control terminal device of the aircraft, or a server. The control terminal device can include, but is not limited to, mobile phones, computers, smart wearable devices, smart vehicle devices, etc., and this application's embodiments do not impose any limitations. The server can be an independent physical server, a server cluster or distributed system composed of multiple physical servers, or a cloud server providing basic cloud computing services such as cloud services, cloud databases, cloud computing, big data, and artificial intelligence platforms, etc., and this application's embodiments do not impose any limitations. Optionally, this switching method can also be executed collaboratively by multiple electronic devices with computing power. For ease of explanation, subsequent embodiments will be described as being executed by a switching device.

[0025] See Figure 1 , Figure 1 This is a flowchart of a communication link switching method provided in an embodiment of this application. The communication link switching method can be executed by a switching device, and the method may include at least the following steps: Step 1: In response to the current time reaching the handover judgment time, or the link quality of the primary link at the current time being less than the link quality threshold of the primary link, update the link handover threshold and handover judgment period according to the channel quality of the link at each time within the preset time window; wherein, the updated handover judgment period is used to determine the next handover judgment time; the cutoff time of the preset time window is the current time; the link quality and channel quality of the primary link at time A are calculated based on multiple channel quality indicators of the primary link at time A, and the link quality and channel quality of the backup link at time A are calculated based on multiple channel quality indicators of the backup link at time A, where time A represents any time.

[0026] Taking existing dual-mode communication systems as an example, such as Figure 2 As shown in the diagram, the Airborne Communication Unit (ACU), also known as the switching device mentioned above, is deployed on the aircraft and is equipped with a 1.4GHz self-organizing network module and a 4G cellular communication module. The Ground Communication Unit (GCU), deployed at a ground base station or control terminal, is equipped with a 1.4GHz self-organizing network receiving module. The 4G base station provides cellular network access capabilities. The ACU connects to the GCU via the 1.4GHz self-organizing network module, thereby communicating with the ground client. The ACU also connects to the public network via the 4G base station and communicates with the ground client through a proxy server. Therefore, in the dual-mode communication system, the primary link and the backup link are either a 1.4G link and a 4G link, or a 4G link and a 1.4G link.

[0027] It should be noted that a switching judgment period is set initially, for example, a switching judgment is performed on one side every 60 seconds. That is, a switching judgment is performed at the beginning (0 seconds), and then a switching judgment is performed again at 60 seconds.

[0028] To facilitate determining whether the current time has reached the switching judgment time, a timestamp can be set. For example, the initial time is assigned a value of 0 to the timestamp. The difference between the current time and the timestamp is used to determine whether the switching judgment time has reached. After a switching judgment is performed at 60 seconds, the value of 60 (i.e. the switching judgment time) is assigned to the timestamp. Based on this timestamp, the next switching judgment time can be determined.

[0029] It should be noted that, in order to improve response speed, the air communication unit (ACU) will acquire the channel status in real time, specifically the channel quality indicators. The channel quality indicators for the 1.4G link can include the received signal strength, reference signal received power, and signal-to-noise ratio (SNR) of the 1.4G link, while the channel quality indicators for the 4G link can include the received signal strength, reference signal received power, SNR plus interference ratio, and reference signal received quality.

[0030] Based on the acquired raw channel quality indices, the link quality and channel quality of the corresponding link can be calculated. The formulas for link quality and channel quality can be the same, but the weighting coefficients can be different. For example, link quality might emphasize RSSI, while channel quality used for handover might emphasize SNR. The link quality can be compared with the corresponding link quality threshold, and if the link quality is good, channel quality can be further used for decision-making.

[0031] The channel quality of a 1.4G link can be expressed as: Q1=w11*f(RSSI-1)+w12*f(RSRP-1)+w13*f(SNR); In the formula, Q1 represents the channel quality of the 1.4G link, w11, w12, and w13 are weighting coefficients, and w11+w12+w13=1. The weighting coefficients can be set according to service requirements, such as flight capability, geographical environment (city / suburb), data transmission requirements, and historical link stability. RSSI-1, RSRP-1, and SNR represent the received signal strength, reference signal received power, and signal-to-noise ratio of the 1.4G link, respectively. f is a preprocessing function, which processes the original channel quality indicators. Specifically, it first performs exponential weighted moving average smoothing on the channel quality indicators to eliminate short-term fluctuations, and then normalizes the smoothed channel quality indicators. The normalization method can be Min-Max normalization, Sigmoid function, or linear mapping, etc., to uniformly map indicators of different dimensions and ranges to [0, 10] or other standard numerical ranges, which facilitates subsequent weighted calculations.

[0032] f(x t =Normalize(EWMA(x) t ))= Normalize(α* x t +(1-α) *EWMA(x t-1 )); In the formula, x t and x t-1 The channel quality metrics at times t and t-1 are f(x) and f(t-1), respectively. t ) represents x t Preprocessing is performed; Normalize represents the normalization operation. If the min-max normalization method is used, f(x) t )=[( α* x t +(1-α) *EWMA(x t-1 )-x min ) / (x max -x min )]*10,x max and x min These are the maximum and minimum channel quality indices, respectively. EWMA stands for Exponentially Weighted Moving Average Smoothing, where α is the smoothing coefficient, 0 < α ≤ 1, and can take values ​​such as 0.2, 0.3, 0.8, 0.9, etc.

[0033] Link quality is used to evaluate the quality of a link. The formula for calculating the link quality of a 1.4G link can be expressed as: Q3=w14*f(RSSI-1)+w15*f(RSRP-1)+w16*f(SNR); In the formula, Q3 represents the link quality of the 1.4G link, w14, w15, and w16 are weighting coefficients, and w14 + w15 + w16 = 1. The weighting coefficients can be set according to service requirements. They can be set to use the same set of weighting parameters as Q1, or they can be set to different weighting parameters. For example, for the minimum requirements of link quality, the link quality focuses more on the RSSI-1 value, while the channel quality used for handover focuses more on the SNR value. For example, the weighting coefficients corresponding to Q1 can be set to 0.2, 0.3, and 0.5, while the weighting coefficients corresponding to Q3 can be set to 0.5, 0.3, and 0.2.

[0034] Similarly, the link channel quality of a 4G link can be expressed as: Q2=w21*f(RSSI-2)+w22*f(RSRP-2)+w23*f(SINR)+w24*f(RSRQ); In the formula, Q2 is the channel quality of the 4G link, w21, w22, w23 and w24 are weighting coefficients, w21+w22+w23+w24=1, RSSI-2, RSRP-2, SINR and RSRQ are the received signal strength, reference signal received power, signal-to-noise ratio plus interference ratio and reference signal received quality of the 4G link, respectively.

[0035] The link quality of a 4G link can be expressed as: Q4=w25*f(RSSI-2)+w26*f(RSRP-2)+w27*f(SINR)+w28*f(RSRQ); In the formula, Q4 represents the link quality of the 4G link, and w25, w26, w27, and w28 are weighting coefficients. w25+w26+w27+w28=1. The weighting coefficients can be set according to service requirements. They can be set to use the same set of weighting parameters as Q2, or they can be set to different weighting parameters. For example, for the minimum requirements of link quality, the 4G link focuses more on the RSRP-2 value, while the channel quality used for handover focuses more on the SINR value.

[0036] The above model (i.e. the calculation formula) comprehensively considers multiple signal quality indicators such as RSSI, RSRP, SINR, and SNR, and unifies the dimensions through a normalization function, thereby improving the comprehensiveness and accuracy of link quality assessment. This technique effectively avoids the problem of incorrect handover caused by fluctuations in a single indicator, thus significantly improving the communication stability of the system in complex wireless environments.

[0037] When the link quality of the main link is less than the link quality threshold at the current moment, in order to improve the response speed, the subsequent handover judgment process will be immediately carried out, that is, to determine the latest link handover threshold and handover judgment period, and then to make a handover judgment. The link quality threshold is obtained based on different business scenarios or historical data statistical analysis. For example, the score range is 0 to 10. The 1.4G link quality threshold can be set to 2.0, and the 4G link quality threshold can be set to 2.5.

[0038] It should be noted that, in some embodiments, the link handover threshold and handover judgment period are updated based on the channel quality of the link at each time point within a preset time window. The specific process may include: 11) Calculate the new link switching threshold and channel volatility based on the channel quality of the link at each time point within the preset time window; the preset time window can be set to 10 seconds.

[0039] The new link handover threshold and channel volatility are calculated using the following formulas: Threshold_dynamic=(Sum(X1,...,X N ) / N)+Offset; In the formula, Threshold_dynamic is the new link switching threshold, and X i Sum(X1,...,X) is the absolute value of the channel quality difference between the primary link and the backup link at the i-th time point within a preset time window, 1≤i≤N, where N is the size of the preset time window, and Offset is the offset coefficient, which can be set to 0.3. N ) represents X1~X N The sum of .

[0040] It should be noted that the link switching threshold should have a lower limit and an upper limit. If the threshold is exceeded, the threshold value should be used as the value. The minimum and maximum values ​​of the dynamic threshold can be customized by the user's experience. For example, the minimum value can be set to 1.5 and the maximum value can be set to 2.8.

[0041] Fluctuation=Sum(|S2-S1|,...,|S N -S N-1 |) / (N-1); In the formula, Fluctuation is the channel volatility, S i To represent the channel quality of the main link at time i within a preset time window, Sum(|S2-S1|,...,|S N -S N-1 |) represents |S2-S1|~|S N -S N-1 | Sum of 12) Replace the old link switching threshold with the new one.

[0042] 13. Based on the channel volatility, determine a new handover judgment period and replace the old handover judgment period with the new handover judgment period.

[0043] The process of determining the new handover judgment period can be as follows: if the channel volatility is less than the first threshold, the new handover judgment period is the first period, such as 120 seconds; if the channel volatility is not less than the first threshold and is less than the second threshold, the new handover judgment period is the second period, such as 60 seconds; if the channel volatility is not less than the second threshold, the new handover judgment period is the third period, such as 30 seconds; wherein, the third period is shorter than the second period, and the second period is shorter than the first period; the first threshold and the second threshold are user-defined data, which can be obtained through historical data statistical analysis. For example, if the score range is 0 to 10, the first threshold can be set to 0.8 and the second threshold can be set to 2.0.

[0044] When the signal quality is stable, a longer handover judgment period (e.g., 120 seconds) is adopted. When the signal fluctuates greatly, the handover judgment period is automatically shortened (e.g., 30 seconds) to improve the system response speed. The dynamic adjustment of the link handover threshold avoids the problem of misjudgment under different environments by using a fixed threshold.

[0045] The link switching threshold and switching judgment period are dynamically adjusted according to the actual situation of the link, which can adapt to signal fluctuations in complex low-altitude environments, reduce the false switching rate and communication interruption risk, and avoid unnecessary frequent switching, thus reducing resource consumption.

[0046] Step 2: In response to the following: the link quality of the primary link and the backup link at the current time is not less than the quality threshold of their respective links; the channel quality of the backup link at the current time is greater than the channel quality of the primary link at the current time; and the difference between the channel quality of the backup link and the primary link at the current time is greater than the updated link switching threshold; or in response to the following: the link quality of the primary link at the current time is less than the link quality threshold of the primary link; and the link quality of the backup link at the current time is greater than the link quality threshold of the backup link, control the primary link at the current time to switch to the backup link, and control the backup link at the current time to switch to the primary link.

[0047] Taking the 4G and 1.4G links mentioned above as examples, assuming that the 4G link and the 1.4G link are the primary link and the backup link respectively, if the link quality of the 4G link and the 1.4G link are not less than their respective link quality thresholds, and if the channel quality of the 1.4G link is greater than the channel quality of the 4G link, that is, the greater quality exceeds the link switching threshold, then a primary / backup switch can be performed, and the better-quality 1.4G link can be used for communication.

[0048] Similarly, if the link quality of the 4G link is less than the 4G link quality threshold, and the link quality of the 1.4G link is greater than the 1.4G link quality threshold, then a primary / backup switch can be performed directly.

[0049] It should be noted that, in response to the following conditions: the link quality of the primary link and the backup link at the current time is not less than their respective link quality thresholds, the channel quality of the backup link at the current time is greater than the channel quality of the primary link at the current time, and the difference between the channel quality of the backup link and the primary link at the current time is not greater than the updated link switching threshold; or in response to the following conditions: the link quality of the primary link and the backup link at the current time is not less than their respective link quality thresholds, and the channel quality of the backup link at the current time is not greater than the channel quality of the primary link at the current time; or in response to the following conditions: the link quality of the primary link at the current time is not less than the link quality threshold of the primary link, and the link quality of the backup link at the current time is less than the link quality threshold of the backup link, the primary link and the backup link are kept unchanged.

[0050] Taking the 4G and 1.4G links as examples again, if the link quality of both the 4G and 1.4G links is not less than the link quality threshold, and the channel quality of the 1.4G link is greater than that of the 4G link, but the greater quality does not exceed the link switching threshold, then the primary / backup switching can be skipped, and the 4G link can still be used for communication.

[0051] Similarly, if the link quality of both the 4G and 1.4G links is not less than the link quality threshold, and the channel quality of the 1.4G link is not greater than the channel quality of the 4G link, or if the link quality of the 4G link is not less than the 4G link quality threshold, and the link quality of the 1.4G link is less than the 1.4G link quality threshold, then in this case, primary / backup switching is not required, and communication can still be conducted using the 4G link.

[0052] To improve communication reliability and reduce the risk of data loss, in some embodiments, the above method further includes controlling the concurrent communication of the main link and the backup link in response to the current link quality being less than the main link quality threshold and the current backup link quality being less than or equal to the backup link quality threshold. During concurrent communication, if the link quality of the main link or the backup link improves, the frequency of concurrent communication is gradually reduced, and communication is ultimately carried out using the main link or the backup link. That is, if the link quality of the main link improves, communication is ultimately carried out using the main link, and if the link quality of the backup link improves, communication is ultimately carried out using the backup link.

[0053] It should be noted that concurrent communication refers to the transmission of the same data packets via 1.4G and 4G links, creating communication redundancy. This mechanism significantly improves the fault tolerance of communication, and is particularly suitable for applications with high data continuity requirements, such as low-altitude aircraft and industrial drones, effectively reducing the risk of data loss due to link interruptions.

[0054] During concurrent transmission of dual links, the link quality of the primary link and the backup link is continuously evaluated. If the link quality of the primary link or the backup link recovers or gradually recovers, the frequency of concurrent transmission can be gradually reduced and eventually exited from concurrent mode. If the link quality of the primary link and the backup link continues to deteriorate, the fault should be reported in a timely manner.

[0055] To prevent system instability caused by multiple switchings in a short period of time, a switching cooldown period is set in some implementations. Specifically, if the link quality of the primary link is not detected to be less than or equal to the primary link quality threshold within a preset time after a primary link and backup link switch is performed, the primary link and backup link switch will not be performed under any circumstances.

[0056] During the handover cooling-off period, even if a change in channel quality is detected, no new handover will be triggered. Link quality still needs to be continuously monitored during the handover cooling-off period. If the link quality of the primary link is less than or equal to the link quality threshold of the primary link, or if the link quality of both the primary link and the backup link is less than or equal to the link quality threshold, the handover will be forcibly terminated from the cooling-off period. After the cooling-off period ends, the normal handover judgment logic will be restored.

[0057] The above method uses multiple channel quality indicators of the link to calculate the channel quality, which can effectively avoid the problem of false handover caused by fluctuation of a single indicator. According to the multiple channel quality indicators of each link within the preset time window, the link handover threshold and handover judgment period are updated, which can make the link handover threshold and handover judgment period adapt to the signal fluctuation in the complex low-altitude environment, reduce the false handover rate and the risk of communication interruption, and avoid unnecessary frequent handover, thus reducing resource consumption.

[0058] See Figure 3 , Figure 3 This is a block diagram of a communication link switching device provided in an embodiment of this application. Figure 3 An embodiment is a virtual device that can be loaded and executed by a computer device, which may include the aforementioned switching device. Figure 3 The apparatus may include an update module and a switching module, which, when used to execute the above-described communication link switching method, can: The update module, in response to the current time reaching the handover judgment time or the current time's main link link quality being less than the main link link quality threshold, updates the link handover threshold and handover judgment period based on the channel quality of the link at each time within a preset time window; wherein, the updated handover judgment period is used to determine the next handover judgment time; the cutoff time of the preset time window is the current time.

[0059] The switching module, in response to the following conditions: the link quality of both the primary link and the backup link at the current time is not less than their respective link quality thresholds; the channel quality of the backup link at the current time is greater than the channel quality of the primary link at the current time; and the difference between the channel quality of the backup link and the primary link at the current time is greater than the updated link switching threshold; or in response to the following conditions: the link quality of the primary link at the current time is less than the primary link's link quality threshold; and the link quality of the backup link at the current time is greater than the backup link's link quality threshold, controls the primary link at the current time to switch to the backup link, and controls the backup link at the current time to switch to the primary link. The link quality and channel quality of the primary link at time A are calculated based on various channel quality indicators of the primary link at time A; the link quality and channel quality of the backup link at time A are calculated based on various channel quality indicators of the backup link at time A.

[0060] The aforementioned device uses multiple channel quality indicators of the link to calculate channel quality, which can effectively avoid the problem of false handover caused by fluctuation of a single indicator. Based on multiple channel quality indicators of each link within a preset time window, the link handover threshold and handover judgment period are updated, which can make the link handover threshold and handover judgment period adapt to signal fluctuations in complex low-altitude environments, reduce false handover rate and communication interruption risk, and avoid unnecessary frequent handovers, thus reducing resource consumption.

[0061] This application also relates to a computer-readable storage medium that stores one or more programs, the one or more programs including instructions that, when executed by a computing device, cause the computing device to perform a communication link switching method.

[0062] This application also relates to a computer device including one or more processors and one or more memories, wherein one or more programs are stored in the one or more memories and configured to be executed by the one or more processors, and the one or more programs include instructions for performing a communication link switching method.

[0063] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0064] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0065] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1The function specified in one or more boxes.

[0066] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0067] The above are merely embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of the claims of the present invention pending approval.

Claims

1. A communication link switching method, characterized in that, include: In response to the arrival of the handover judgment time at the current time, or the link quality of the main link at the current time being less than the link quality threshold of the main link, the link handover threshold and handover judgment period are updated according to the channel quality of the link at each time within the preset time window; wherein, the updated handover judgment period is used to determine the next handover judgment time; the end time of the preset time window is the current time; In response to the following: the link quality of the primary link and the backup link at the current time is not less than their respective link quality thresholds; the channel quality of the backup link at the current time is greater than the channel quality of the primary link at the current time; and the difference between the channel quality of the backup link and the primary link at the current time is greater than the updated link switching threshold; or in response to the following: the link quality of the primary link at the current time is less than the primary link's link quality threshold; and the link quality of the backup link at the current time is greater than the backup link's link quality threshold, the primary link at the current time is switched to the backup link, and the backup link at the current time is switched to the primary link. The link quality and channel quality of the primary link at time A are calculated based on various channel quality indicators of the primary link at time A; the link quality and channel quality of the backup link at time A are calculated based on various channel quality indicators of the backup link at time A.

2. The method according to claim 1, characterized in that, The links include 1.4G links and 4G links; The formula for calculating the channel quality of a 1.4G link is: Q1=w11*f(RSSI-1)+w12*f(RSRP-1)+w13*f(SNR); In the formula, Q1 is the channel quality of the 1.4G link, w11, w12 and w13 are weighting coefficients, RSSI-1, RSRP-1 and SNR are the received signal strength, reference signal received power and signal-to-noise ratio of the 1.4G link, respectively, and f is a preprocessing function, which performs exponential weighted moving average smoothing on the channel quality index and normalization on the smoothed channel quality index. The formula for calculating the channel quality of a 4G link is: Q2=w21*f(RSSI-2)+w22*f(RSRP-2)+w23*f(SINR)+w24*f(RSRQ); In the formula, Q2 is the channel quality of the 4G link, w21, w22, w23 and w24 are weighting coefficients, and RSSI-2, RSRP-2, SINR and RSRQ are the received signal strength, reference signal received power, signal-to-noise ratio plus interference ratio and reference signal received quality of the 4G link, respectively. The formula for calculating the link quality of a 1.4G link is: Q3=w14*f(RSSI-1)+w15*f(RSRP-1)+w16*f(SNR); In the formula, Q3 represents the link quality of the 1.4G link, and w14, w15, and w16 are weighting coefficients; The formula for calculating the link quality of a 4G link is: Q4=w25*f(RSSI-2)+w26*f(RSRP-2)+w27*f(SINR)+w28*f(RSRQ); In the formula, Q4 represents the link quality of the 4G link, and w25, w26, w27, and w28 are weighting coefficients.

3. The method according to claim 1, characterized in that, Based on the channel quality of the link at each moment within a preset time window, update the link handover threshold and handover judgment period, including: Based on the channel quality of the link at each moment within the preset time window, calculate the new link handover threshold and channel volatility. Replace the old link switching threshold with the new one; Based on the channel volatility, a new handover decision period is determined and replaced with the old handover decision period.

4. The method according to claim 3, characterized in that, The new link handover threshold and channel volatility are calculated using the following formulas: Threshold_dynamic=(Sum(X1,...,X N ) / N)+Offset; In the formula, Threshold_dynamic is the new link switching threshold, and X i Sum(X1,...,X) is the absolute value of the channel quality difference between the primary link and the backup link at time i within a preset time window, where 1 ≤ i ≤ N, N is the size of the preset time window, Offset is the offset coefficient, and Sum(X1,...,X) is the value of the channel quality difference between the primary link and the backup link at time i within a preset time window. N ) represents X1~X N The sum of; Fluctuation=Sum(|S2-S1|,...,|S N -S N-1 |) / (N-1); In the formula, Fluctuation is the channel volatility, S i To represent the channel quality of the main link at the i-th time point within a preset time window, Sum(|S2-S1|,...,|S N -S N-1 |) represents |S2-S1|~|S N -S N-1 The sum of |.

5. The method according to claim 3, characterized in that, Based on channel volatility, a new handover decision period is determined, including: If the channel volatility is less than the first threshold, the new handover determination period is the first period. If the channel volatility is not less than the first threshold and is less than the second threshold, the new handover judgment period is the second period. If the channel volatility is not less than the second threshold, the new handover judgment period is the third period; wherein the third period is shorter than the second period, and the second period is shorter than the first period.

6. The method according to claim 1, characterized in that, The method further includes: In response to the following conditions: the link quality of the primary link and the backup link at the current time is not less than their respective link quality thresholds, the channel quality of the backup link at the current time is greater than the channel quality of the primary link at the current time, and the difference between the channel quality of the backup link and the primary link at the current time is not greater than the updated link switching threshold; or in response to the following conditions: the link quality of the primary link and the backup link at the current time is not less than their respective link quality thresholds, and the channel quality of the backup link at the current time is not greater than the channel quality of the primary link at the current time; or in response to the following conditions: the link quality of the primary link at the current time is not less than the link quality threshold of the primary link, and the link quality of the backup link at the current time is less than the link quality threshold of the backup link, the primary link and the backup link remain unchanged. In response to the current link quality being less than the primary link quality threshold and the current backup link quality being less than or equal to the backup link quality threshold, the system controls the primary link and backup link to communicate concurrently. During concurrent communication, if the link quality of the primary link or backup link improves, the frequency of concurrent communication is gradually reduced, and communication is ultimately conducted via the primary link or backup link.

7. The method according to claim 1, characterized in that, The method further includes: If, within a preset timeframe after a primary link and backup link switchover, no primary link and backup link switchover is performed under any circumstances, and no primary link and backup link switchover is detected that the link quality of the primary link is less than or equal to the primary link's link quality threshold, then a primary link and backup link switchover will not be performed under any circumstances.

8. A communication link switching device, characterized in that, include: The update module, in response to the current time reaching the handover judgment time or the current time's main link link quality being less than the main link link quality threshold, updates the link handover threshold and handover judgment period based on the channel quality of the link at each time within a preset time window; wherein, the updated handover judgment period is used to determine the next handover judgment time; the cutoff time of the preset time window is the current time; The switching module, in response to the following conditions: the link quality of both the primary link and the backup link at the current time is not less than their respective link quality thresholds; the channel quality of the backup link at the current time is greater than the channel quality of the primary link at the current time; and the difference between the channel quality of the backup link and the primary link at the current time is greater than the updated link switching threshold; or in response to the following conditions: the link quality of the primary link at the current time is less than the primary link's link quality threshold; and the link quality of the backup link at the current time is greater than the backup link's link quality threshold, controls the primary link at the current time to switch to the backup link, and controls the backup link at the current time to switch to the primary link. The link quality and channel quality of the primary link at time A are calculated based on various channel quality indicators of the primary link at time A; the link quality and channel quality of the backup link at time A are calculated based on various channel quality indicators of the backup link at time A.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores one or more programs, the one or more programs including instructions that, when executed by a computing device, cause the computing device to perform the method of any one of claims 1 to 7.

10. A computer device, characterized in that, include: One or more processors and one or more memories, one or more programs stored in one or more memories and configured to be executed by one or more processors, the one or more programs including instructions for performing the method of any one of claims 1 to 7.

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