A method and system for airborne surveillance data processing

Abstract

This invention relates to the field of data processing technology and discloses an airborne surveillance data processing method and system. The method involves: when both the primary and secondary 4G links are interrupted, triggering a blind zone buffer and writing surveillance data into the SRAM level 1 buffer; when the data volume in the SRAM level 1 buffer reaches a threshold or the transfer cycle is reached, transferring the surveillance data to the eMMC level 2 storage; after the communication link is restored, reading the surveillance data and sending supplementary reporting data packets to the surveillance platform; confirming each supplementary reporting data packet in the surveillance platform and updating the supplementary reporting status flag in the eMMC level 2 storage; and re-reporting surveillance data with an unconfirmed status flag when the device is powered on again to the surveillance platform. This invention achieves orderly and complete backhaul of blind zone historical data and ensures that real-time surveillance services do not interfere with each other, guaranteeing the surveillance platform's continuous tracking of the aircraft's entire flight trajectory and safety events.

Description

Technical Field

[0001] This invention relates to the field of data processing technology, and in particular to an airborne surveillance data processing method and system. Background Technology

[0002] With the rapid development of the low-altitude economy, the application scenarios of low-altitude aircraft such as drones are becoming increasingly widespread. The proliferation of low-altitude aircraft has also brought challenges to safety supervision. Traditional supervision methods often suffer from problems such as being "invisible, unconnected, and unresponsive," making it difficult to effectively and in real-time monitor and manage low-altitude aircraft. In remote monitoring systems for low-altitude aircraft based on public mobile communication networks, the stability of the data link between the aircraft and the monitoring platform is crucial. However, due to geographical conditions or urban building obstructions, temporary interruptions in communication links are inevitable, creating communication blind spots.

[0003] In existing technologies, some systems rely solely on a single signal strength indicator to trigger buffering after detecting a link interruption. This is prone to false triggers due to instantaneous signal fluctuations. Buffering mechanisms typically use a single volatile memory with limited capacity; unexpected power outages will result in the loss of all buffered data, leading to low reliability. After communication is restored, buffered data is often retransmitted in a burst, easily clogging the newly restored communication link, consuming bandwidth for real-time data, and treating all data equally. High-priority alarm data may be buried under a large amount of ordinary status data, delaying response time and compromising the traceability of monitoring data throughout the entire process. Summary of the Invention

[0004] The main objective of this invention is to provide an airborne surveillance data processing method and system. By comprehensively analyzing the dual-link signal strength parameters and the number of consecutive heartbeat timeouts, this invention avoids false triggering caused by a single signal strength indicator. The blind zone cache is only triggered when both the master and slave links simultaneously meet the interruption conditions, eliminating the pseudo-caching problem caused by instantaneous fluctuations in a single link, saving storage resources, and thus achieving orderly and complete backhaul of blind zone historical data and non-interference with real-time surveillance operations. This ensures the continuous tracking of the aircraft's entire flight trajectory and safety events by the surveillance platform.

[0005] To achieve the above objectives, the present invention provides an airborne surveillance data processing method, comprising the following steps: When both the primary 4G link and the secondary 4G link are interrupted, the blind zone cache is triggered and the monitoring data is written to the SRAM level 1 cache. When the amount of data in the SRAM level 1 cache reaches the water level threshold or the transfer cycle is reached, the monitoring data is transferred to the eMMC level 2 storage. After the communication link is restored, the regulatory data is read from the SRAM level 1 cache or eMMC level 2 storage, and a supplementary data packet is sent to the regulatory platform; The monitoring platform confirms the supplementary data packets one by one, updates the supplementary status flag in the eMMC secondary storage, and re-reports the monitoring data with the supplementary status flag set to unconfirmed to the monitoring platform when the device is powered on again.

[0006] Optionally, in a first implementation of the first aspect of the present invention, the step of triggering a blind zone cache and writing regulatory data into the SRAM level 1 cache when both the primary 4G link and the secondary 4G link are interrupted, and transferring the regulatory data to the eMMC level 2 storage when the data volume in the SRAM level 1 cache reaches a water level threshold or the transfer cycle is reached, includes: A sliding window filter is applied to the first signal strength parameter of the primary 4G link to obtain the first signal strength filtered value; a sliding window filter is applied to the second signal strength parameter of the secondary 4G link to obtain the second signal strength filtered value. The primary 4G link is determined to be interrupted based on the first signal strength filter value and the first consecutive heartbeat timeout count of the primary 4G link; the secondary 4G link is determined to be interrupted based on the second signal strength filter value and the second consecutive heartbeat timeout count of the secondary 4G link. When both the primary 4G link and the secondary 4G link are interrupted, a blind zone buffer is triggered. After the blind zone cache is triggered, the monitoring data is written to the SRAM level 1 cache, and when the amount of data in the SRAM level 1 cache reaches the water level threshold or the transfer cycle is reached, the monitoring data is batch-appended and transferred to the eMMC level 2 storage.

[0007] Optionally, in a second implementation of the first aspect of the present invention, the step of writing the monitoring data into the SRAM level 1 cache after the blind zone cache is triggered, and batch appending and transferring the monitoring data to the eMMC level 2 storage when the data volume in the SRAM level 1 cache reaches the water level threshold or the transfer cycle is reached, includes: After the blind zone cache is triggered, the monitoring data is appended with a BeiDou / GPS time stamp and a CRC32 checksum, and written to the SRAM level 1 cache in a circular queue. When the amount of data in the SRAM Level 1 cache reaches the water level threshold or the transfer cycle is reached, the monitoring data is transferred in batches to the eMMC Level 2 storage in an append-only manner.

[0008] Optionally, in a third implementation of the first aspect of the present invention, the step of batch transferring the monitoring data to eMMC secondary storage in an append-only manner when the data volume in the SRAM level 1 cache reaches the water level threshold or the transfer cycle is reached includes: The amount of data in the SRAM L1 cache is compared with the water level threshold, and the transfer cycle is monitored simultaneously. When the amount of data reaches the water level threshold or the transfer cycle is reached, the regulatory data to be transferred is read from the SRAM level 1 cache, and the regulatory data is written to the eMMC level 2 storage in batches using an append write method.

[0009] Optionally, in the fourth implementation of the first aspect of the present invention, after the regulatory data is written to the eMMC secondary storage, the timestamp and sequence number of the regulatory data are extracted, and an index entry containing the timestamp, the sequence number and the supplementary reporting status flag is established for each piece of regulatory data in the file index of the eMMC secondary storage. The supplementary reporting status flag in the index entry is initialized to an unconfirmed state to obtain persistent backup data.

[0010] Optionally, in a fifth implementation of the first aspect of the present invention, the step of reading the regulatory data from the SRAM level 1 cache or eMMC level 2 storage after the communication link is restored, and sending a supplementary reporting data packet to the regulatory platform, includes: After the communication link is restored, the regulatory data is first read from the SRAM Level 1 cache in ascending order of timestamp. When the SRAM Level 1 cache is empty, the regulatory data is then read from the eMMC Level 2 storage in ascending order of timestamp. The monitoring data is read in a high-priority alarm queue over a low-priority status queue, and supplementary data packets are sent to the monitoring platform at a controlled rate lower than the real-time data transmission rate.

[0011] Optionally, in the sixth implementation of the first aspect of the present invention, the read monitoring data is parsed to classify the rapid acceleration event frame, attitude change event frame and geofence crossing record as alarm monitoring data, and the positioning frame, attitude cycle frame and working condition frame as status monitoring data. The monitoring data for the alarm category is written to the high-priority alarm queue, and the monitoring data for the status category is written to the low-priority status queue.

[0012] Optionally, in the seventh implementation of the first aspect of the present invention, the step of confirming the supplementary data packet packet by packet in the monitoring platform, updating the supplementary status flag in the eMMC secondary storage, and re-reporting the monitoring data with the supplementary status flag set to unconfirmed to the monitoring platform when the device is powered on again includes: The monitoring platform performs CRC32 verification on each of the supplementary data packets and returns confirmation response information. Based on the timestamp and sequence number carried in the confirmation response information, the supplementary status flag of the corresponding index entry in the file index of the eMMC secondary storage is updated to the confirmed status. When the device is powered on again, the file index of the eMMC secondary storage is scanned, and the regulatory data corresponding to the index entries whose supplementary reporting status is marked as unconfirmed is resubmitted to the regulatory platform.

[0013] Optionally, in the eighth implementation of the first aspect of the present invention, the step of performing CRC32 verification on each packet of the supplementary reporting data packet on the monitoring platform and returning confirmation response information, and updating the supplementary reporting status flag of the corresponding index entry in the file index of the eMMC secondary storage to the confirmed status according to the timestamp and sequence number carried in the confirmation response information, includes: Each received supplementary data packet is subjected to CRC32 verification. After the CRC32 verification is successful, an acknowledgment response information carrying the timestamp and sequence number of the supplementary data packet is returned to the airborne monitoring equipment. Based on the timestamp and sequence number carried in the confirmation response information, the corresponding index entry is located in the file index of the eMMC secondary storage, and the supplementary reporting status flag of the index entry is updated from unconfirmed to confirmed.

[0014] The present invention also provides an airborne surveillance data processing system, comprising: The data transfer module is used to trigger the blind zone cache and write the monitoring data into the SRAM level 1 cache when both the main 4G link and the secondary 4G link are interrupted. When the amount of data in the SRAM level 1 cache reaches the water level threshold or the transfer cycle is reached, the monitoring data is transferred to the eMMC level 2 storage. The data supplementation module is used to read the regulatory data from the SRAM level 1 cache or eMMC level 2 storage after the communication link is restored, and send the supplementation data packet to the regulatory platform. The data monitoring module is used to confirm the supplementary data packets one by one in the monitoring platform, update the supplementary status flag in the eMMC secondary storage, and re-report the monitoring data with the supplementary status flag set to unconfirmed to the monitoring platform when the device is powered on again.

[0015] In summary, this invention, through comprehensive analysis of dual-link signal strength parameters and the number of consecutive heartbeat timeouts, avoids false triggering caused by a single signal strength indicator. The blind zone cache is only triggered when both master and slave links simultaneously meet the interruption condition, eliminating the pseudo-caching problem caused by instantaneous fluctuations in a single link and saving storage resources. A two-level redundant storage architecture consisting of SRAM level 1 cache and eMMC level 2 storage persistently backs up monitoring data generated during the blind zone to the eMMC level 2 storage via append-only writes. A supplementary reporting status flag is maintained for each cached data unit in the file index. Even if the device experiences an unexpected power outage during the blind zone, the data already persisted in the eMMC can still be resumed in ascending order of timestamps based on the unconfirmed index entries in the file index after power is restored, solving the problem of total data loss in traditional single volatile storage solutions during power outages. After communication is restored, this invention writes alarm-type regulatory data and status-type regulatory data into a high-priority alarm queue and a low-priority status queue, respectively. Supplementary reporting data packets carrying historical supplementary reporting identifiers are sent to the regulatory platform at a controlled rate lower than the real-time data transmission rate, according to the priority scheduling order of the high-priority queue. This ensures that key alarm data such as rapid acceleration event frames and attitude change event frames are prioritized for transmission after communication is restored, while avoiding the impact of supplementary reporting traffic on the real-time data link. This achieves orderly and complete transmission of historical data in blind spots and non-interference with real-time regulatory services, ensuring the regulatory platform's continuous tracking of the aircraft's entire flight trajectory and safety events. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the steps of an airborne surveillance data processing method in one embodiment of the present invention; Figure 2 This is a schematic diagram illustrating the steps of transferring regulatory data to eMMC secondary storage in an embodiment of the present invention; Figure 3 This is a schematic diagram illustrating the steps of sending supplementary data packets to the regulatory platform in an embodiment of the present invention; Figure 4 This is a schematic diagram illustrating the steps of resubmitting regulatory data to the regulatory platform in an embodiment of the present invention; Figure 5 This is a block diagram of the airborne surveillance data processing system in an embodiment of the present invention.

[0017] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0019] Reference Figure 1 This embodiment provides an airborne surveillance data processing method, including the following steps: S1, when both the primary 4G link and the secondary 4G link are interrupted, the blind zone buffer is triggered and the regulatory data is written to the SRAM level 1 cache. When the amount of data in the SRAM level 1 cache reaches the water level threshold or the transfer cycle is reached, the regulatory data is transferred to the eMMC level 2 storage. S2, after the communication link is restored, reads the regulatory data from the SRAM level 1 cache or eMMC level 2 storage and sends the supplementary data packet to the regulatory platform; S3 confirms the supplementary data packets one by one in the regulatory platform, updates the supplementary status flag in the eMMC secondary storage, and re-reports the regulatory data with the supplementary status flag set to unconfirmed to the regulatory platform when the device is powered on again.

[0020] In one example, such as Figure 2 When both the primary and secondary 4G links are interrupted, the blind zone cache is triggered and the monitoring data is written to the SRAM Level 1 cache. When the data volume in the SRAM Level 1 cache reaches the water level threshold or the transfer cycle is reached, the monitoring data is transferred to the eMMC Level 2 storage, including: S11, Perform sliding window filtering on the first signal strength parameter of the main 4G link to obtain the first signal strength filtered value; Perform sliding window filtering on the second signal strength parameter of the secondary 4G link to obtain the second signal strength filtered value; S12, determine whether the main 4G link is interrupted based on the first signal strength filter value and the first consecutive heartbeat timeout count of the main 4G link; determine whether the secondary 4G link is interrupted based on the second signal strength filter value and the second consecutive heartbeat timeout count of the secondary 4G link. S13, when both the primary 4G link and the secondary 4G link are interrupted, the blind zone buffer is triggered; S14: After the blind zone cache is triggered, the regulatory data is written to the SRAM level 1 cache. When the amount of data in the SRAM level 1 cache reaches the water level threshold or the transfer cycle is reached, the regulatory data is batch-appended and transferred to the eMMC level 2 storage.

[0021] In this example, a communication status monitoring unit and a multi-level storage management unit are set up inside the airborne monitoring equipment. The communication status monitoring unit periodically collects the first signal strength parameter of the main 4G link and the second signal strength parameter of the slave 4G link, and smooths the instantaneous sampled values ​​according to the sliding window filtering method to obtain the first signal strength filtered value and the second signal strength filtered value. This reduces the interference of instantaneous fluctuations on the interruption judgment result in mountainous, canyon, and urban obstruction edge scenarios, and avoids misjudging the link failure due to a single sampling jitter. The first signal strength filter value is combined with the first consecutive heartbeat timeout count of the primary 4G link for determination, and the second signal strength filter value is combined with the second consecutive heartbeat timeout count of the secondary 4G link for determination. The consecutive heartbeat timeout count is 3, the timeout duration of a single connection request is not less than 3 seconds, and the signal strength threshold is -100 dBm. When the primary 4G link meets any of the following single-link interruption criteria, it is determined to be interrupted: the single-link interruption criteria include 3 consecutive heartbeat timeouts or the first signal strength filter value is continuously lower than -100 dBm. When the secondary 4G link meets any of the following single-link interruption criteria, it is determined to be interrupted: the single-link interruption criteria include 3 consecutive heartbeat timeouts or the second signal strength filter value is continuously lower than -100 dBm. When both the primary and secondary 4G links are determined to be interrupted, a blind zone buffer is triggered, forming a "dual-link interruption" triggering mechanism to suppress the pseudo-buffering caused by short-term fading of a single link. Before the formal trigger, the changing trends of the first and second signal strength filter values ​​are continuously monitored within a continuous sampling period. When both show a continuous downward trend and are simultaneously below the warning threshold, a blind zone warning signal is generated in advance, and the capacity of the circular queue in the SRAM level 1 cache is expanded. The queue occupancy ratio of low-priority status-type monitoring data is compressed, and the freed-up write space is preferentially allocated to the alarm-type monitoring data buffer to reduce the probability of high-frequency data loss at the blind zone boundary. The warning threshold is set to -95 dBm, which is used to identify the link attenuation trend in advance before the formal triggering of the dual-link interruption determination and to drive the pre-expansion control of the SRAM level 1 cache. The airborne monitoring equipment uniformly encapsulates monitoring data such as positioning frames, attitude cycle frames, operating condition frames, rapid acceleration event frames, attitude change event frames, and geofence boundary crossing records. A Beidou / GPS time stamp and CRC32 check code are added to each monitoring data, and then it is preferentially written to the SRAM level 1 cache in a circular queue. The SRAM level 1 cache has a dedicated capacity of 6 MB to meet the high-frequency write requirements during the blind zone. The multi-level storage management unit continuously compares the current data volume of the SRAM level 1 cache with the water level threshold and monitors the transfer cycle simultaneously. When the data volume of the SRAM level 1 cache reaches the water level threshold or the transfer cycle is reached, the data to be transferred is read in batches from the SRAM level 1 cache and written to the eMMC level 2 storage in an append write mode.The transfer period is set to 5 or 10 seconds, with 10 seconds used when the expected duration of the blind zone is short and the probability of link recovery is high, and 5 seconds used when link fluctuations are significant or the expected duration of the blind zone is long. The eMMC secondary storage capacity is 32 GB, used to store cached regulatory data in scenarios of long-term blind zones or abnormal power outages. After the regulatory data is written to the eMMC secondary storage in batches, the timestamp and sequence number are extracted. An index entry containing the timestamp, sequence number, and supplementary reporting status flag is created in the file index of the eMMC secondary storage, and the supplementary reporting status flag is initialized to an unconfirmed state.

[0022] Before triggering the blind zone cache, the process includes: monitoring the changing trends of the first and second signal strength filter values ​​within a continuous sampling period; generating a blind zone warning signal when both the first and second signal strength filter values ​​show a continuous downward trend and are below the warning threshold; dynamically expanding the upper limit of the available write capacity of the circular queue in the SRAM level 1 cache based on the blind zone warning signal, compressing the queue occupancy ratio of low-priority status monitoring data, and allocating the freed space to the write buffer of alarm monitoring data first, resulting in an expanded cache queue; and writing the monitoring data to the expanded cache queue after the blind zone is officially triggered, reducing data loss due to insufficient write capacity at the blind zone boundary.

[0023] In one example, after the blind zone cache is triggered, regulatory data is written to the SRAM Level 1 cache, and when the data volume in the SRAM Level 1 cache reaches the water level threshold or the rollover cycle is reached, the regulatory data is batch-appended and rolled over to the eMMC Level 2 storage, including: After the blind zone cache is triggered, the monitoring data is appended with a BeiDou / GPS time stamp and a CRC32 checksum, and written to the SRAM level 1 cache in a circular queue. When the amount of data in the SRAM Level 1 cache reaches the water level threshold or the transfer cycle is reached, the monitoring data will be transferred to the eMMC Level 2 storage in batches via append write.

[0024] In this example, after the blind zone cache is triggered, the airborne surveillance equipment, through the collaboration of the protocol processing unit and the multi-level storage management unit, completes the encapsulation, writing, and hierarchical transfer of surveillance data. The protocol processing unit uniformly formats the newly generated surveillance data, encapsulating positioning information, attitude information, status information, and alarm information into standard data units. A BeiDou / GPS time stamp and a CRC32 checksum are appended to the end of each surveillance data entry, ensuring that each data entry possesses both accurate timing positioning and integrity verification capabilities. The time stamp uses millisecond-level time stamps, while the CRC32 checksum is used to identify whether bit flips, truncation, or splicing anomalies have occurred in the data units during cache writing, secondary transfer, and supplementary reporting. After encapsulation, the multi-level storage management unit writes the surveillance data into the SRAM level 1 cache in a circular queue, leveraging the high access speed of SRAM to absorb the high-frequency, continuous data streams arriving during the blind zone. The SRAM level 1 cache has a capacity of 6 MB and can reserve higher write priority for alarm-type surveillance data at the blind zone boundary stage in conjunction with early warning signals, thereby reducing the probability of critical data being overwritten during cache congestion. As regulatory data is continuously written, the multi-level storage management unit continuously monitors the current data volume in the SRAM level 1 cache and synchronously monitors whether the transfer cycle has been reached. When the data volume in the SRAM level 1 cache reaches the water level threshold, or when the transfer cycle is reached, the batch transfer process is initiated, with the transfer cycle being 5 or 10 seconds. After the transfer is initiated, the system reads the regulatory data to be transferred from the SRAM level 1 cache that has not yet been persisted, and writes it in batches to the eMMC level 2 storage using an append-only method. This ensures that the newly written data is continuously appended to the end of the existing log files, avoiding the additional overhead caused by frequently rebuilding the file structure. The eMMC level 2 storage has a capacity of 32 GB, used to retain transferred data in long-term blind spots or abnormal power outage scenarios. Due to the append-only method, the transfer process can continuously expand the persistent data area without destroying the continuity of existing historical records. At the same time, combined with the timestamp field, supplementary reports are organized in chronological order after subsequent communication is restored. By combining CRC32 checksums, integrity verification is completed throughout the entire process from reading from the SRAM Level 1 cache to writing to the eMMC Level 2 storage, thereby ensuring that the regulatory data entering the Level 2 storage has the characteristics of being traceable, verifiable, and resubmittable.

[0025] In one example, when the amount of data in the SRAM L1 cache reaches a watermark threshold or the rollover cycle is reached, the regulatory data is batch-rolled to the eMMC L2 storage via append write, including: The amount of data in the SRAM L1 cache is compared with the water level threshold, and the transfer cycle is monitored simultaneously. When the data volume reaches the water level threshold or the transfer cycle is reached, the regulatory data to be transferred is read from the SRAM level 1 cache and written to the eMMC level 2 storage in batches using append write mode.

[0026] In this example, the multi-level storage management unit continuously maintains a set of transfer judgment tasks while the blind zone cache is already established. This process involves real-time statistics of the current valid data volume in the SRAM L1 cache and synchronized timing of the transfer cycle, ensuring that capacity and time criteria take effect in parallel. The SRAM L1 cache is set as a dedicated high-speed cache area with a capacity of 6 MB, and the write pointer, read pointer, and current occupancy are continuously updated during cache writes. Simultaneously, the cache occupancy status is polled at fixed intervals in the transfer control thread, and an independent periodic timer is started to monitor the transfer cycle. The water level threshold is set to 80% of the SRAM L1 cache capacity, corresponding to 4.8 MB, to release cache pressure in advance without affecting the continuity of high-speed writes. The transfer cycle is set to 5 seconds or 10 seconds. A 10-second interval is used when the expected blind zone duration is short and the link recovery probability is high, while a 5-second interval is used when there is mountainous terrain obstruction, cross-regional inspection, or significant link fluctuations, balancing write efficiency under short-term blind zones with persistence security under long-term blind zones. When comparison results indicate that the data volume in the SRAM L1 cache has reached the water level threshold, or when periodic timing results indicate that the transfer cycle has been reached, the multi-level storage management unit triggers a batch transfer process. It reads the currently untransferred regulatory data from the SRAM L1 cache, maintaining the original write order, and writes this regulatory data as a continuous batch to the eMMC L2 storage. The append-only write method eliminates the need to repeatedly rebuild existing file content; it simply appends the current batch of data sequentially to the end of the existing log file. This reduces flash write control overhead and ensures that regulatory data formed at different time periods maintains natural temporal continuity in the eMMC L2 storage. When reading the regulatory data to be transferred, the previously appended BeiDou / GPS timestamp and CRC32 checksum are retained for each piece of regulatory data, ensuring that the data written to the eMMC L2 storage still possesses complete temporal identification and integrity verification. The eMMC L2 storage uses a 32 GB capacity to accommodate regulatory data transferred out in batches from the SRAM L1 cache during periods of inactivity, thus preserving persistently backed-up data even when the device is in an inactivity for extended periods or experiences a sudden power outage.

[0027] In one example, after regulatory data is written to eMMC secondary storage, the timestamp and sequence number of the regulatory data are extracted, and an index entry containing the timestamp, sequence number and supplementary reporting status flag is created for each piece of regulatory data in the file index of eMMC secondary storage. The supplementary reporting status flag in the index entry is initialized to an unconfirmed state to obtain persistent backup data.

[0028] In this example, within the airborne surveillance equipment, a multi-level storage management unit initiates an index registration process after the surveillance data is appended to the eMMC secondary storage. This involves extracting the corresponding timestamp and sequence number for each piece of surveillance data that has been persistently written, and generating an index entry in the file index area of ​​the eMMC secondary storage that corresponds one-to-one with the data entity. The timestamp uses a BeiDou / GPS time stamp added during the encapsulation stage, maintaining millisecond-level precision to ensure that the original time sequence of the surveillance data can be strictly restored during subsequent supplementary reporting. The sequence number is used to distinguish different surveillance data units written consecutively within the same time window, enabling the system to uniquely locate the target data using the combination of "timestamp + sequence number" in situations involving the same time granularity, batch transfers, or restart recovery. In eMMC secondary storage, an independent file index area is maintained for append-written log files. After a batch of regulatory data is written, the index generation thread traverses the batch of regulatory data in the writing order, reading the timestamp and sequence number fields in the data header one by one. Then, the timestamp, sequence number, and supplementary reporting status flag are encapsulated into index entries, and the index entries are written sequentially to the file index area, thereby maintaining a mapping relationship between the data entity area and the index area. The supplementary reporting status flag is uniformly initialized to an unconfirmed state when the index entry is first created. This is because although the regulatory data has been permanently backed up locally, it has not yet been confirmed by the regulatory platform packet by packet, so it cannot be directly regarded as a completed historical supplementary report. Only after the communication link is restored, the regulatory platform completes CRC32 verification of the supplementary reporting data packet and sends back confirmation response information carrying the timestamp and sequence number, can the system locate the corresponding index entry in the file index of eMMC secondary storage based on the timestamp and sequence number, and update the supplementary reporting status flag from the unconfirmed state to the confirmed state. When the device experiences an abnormal power outage during a blind zone, or restarts midway through the resubmission process, the system can directly scan the file index of the eMMC secondary storage after power-on. It then statistically analyzes and filters all index entries whose resubmission status is still unconfirmed, and resubmits the corresponding regulatory data to the regulatory platform in ascending order of timestamp. This avoids duplicate resubmissions of already confirmed data and prevents the omission of unconfirmed data. Index entry generation is limited to occur only after each batch write to the eMMC secondary storage is successful, and an index registration completion flag is returned after the index area is written. Only when both the data entity area and the index area are successfully written is the batch of regulatory data officially recognized as persistent backup data.

[0029] In one example, such as Figure 3 After the communication link is restored, regulatory data is read from the SRAM L1 cache or eMMC L2 storage, and a supplementary reporting data packet is sent to the regulatory platform, including: S21, after the communication link is restored, first read the regulatory data from the SRAM level 1 cache in ascending order of timestamps. When the SRAM level 1 cache is empty, switch to reading the regulatory data from the eMMC level 2 storage in ascending order of timestamps. S22, according to the order of high-priority alarm queue over low-priority status queue, schedule the reading of regulatory data and send supplementary data packets to the regulatory platform at a controlled rate lower than the real-time data transmission rate.

[0030] In this example, a link recovery determination unit, a cache read scheduling unit, and a supplementary reporting control unit are set up inside the airborne surveillance equipment. After the communication link is detected to be restored, an orderly supplementary reporting mechanism constrained by both time sequence and service priority is established. After the communication link is restored, the cache read scheduling unit scans the SRAM level 1 cache and reads it in ascending order according to the timestamp field attached to the surveillance data. The SRAM level 1 cache retains the blind zone historical data that is closest to the current time and has not yet been persisted or supplemented. Priority is given to reading the backhaul link that can shorten the most recent period of historical data from the SRAM level 1 cache. When the SRAM level 1 cache is empty, or all the surveillance data to be supplemented has been read, it automatically switches to the eMMC level 2 storage and continues to read the subsequent surveillance data in ascending order of timestamp based on the timestamp and sequence number recorded in the eMMC level 2 storage file index. This ensures that all surveillance data generated during the blind zone maintains a strict time sequence when it is transmitted back to the surveillance platform, and there will be no time sequence disorder problem where data generated later is supplemented first and data generated earlier is supplemented later. Meanwhile, the supplementary reporting control unit divides the data to be reported into a high-priority alarm queue and a low-priority status queue based on the data type tag or queue attribute of the regulatory data. It always schedules data according to the order of priority: high-priority alarm queues take precedence over low-priority status queues. Specifically, when there are high-risk event data such as attitude anomalies, boundary crossing alarms, or rapid acceleration alarms, regulatory data from the high-priority alarm queue is extracted first to construct supplementary reporting data packets. Only after the high-priority alarm queue has completed its transmission within the current scheduling window does it continue to send routine regulatory data such as positioning, attitude, and operating conditions from the low-priority status queue. To avoid the supplementary reporting data stream congesting the newly restored link again, the supplementary reporting control unit throttles the supplementary reporting rate, sending supplementary reporting data packets to the regulatory platform at a controlled rate lower than the real-time data transmission rate. For example, a supplementary reporting rate of 40 packets / second is used. Since this rate is lower than the reporting rate of real-time regulatory data under normal flight conditions, historical data supplementation can be carried out in parallel while real-time data is continuously transmitted, ensuring that real-time data services and supplementary reporting services do not interfere with each other. During the operation of the supplementary reporting thread, the system prioritizes ensuring that newly generated real-time monitoring data continues to be sent normally through the restored link, while historical supplementary reporting data is pushed sequentially by an independent supplementary reporting thread at a controlled rate. After receiving the supplementary reporting data packet, the monitoring platform inserts the corresponding data into the correct position in the historical data stream according to the timestamp, thereby achieving continuous recovery of flight trajectory, status evolution, and safety events.

[0031] Before reading regulatory data from SRAM Level 1 cache or eMMC Level 2 storage, the process includes: after the communication link is restored, sending a link quality probe heartbeat packet to the regulatory platform; determining whether the link is stable based on the heartbeat confirmation response returned by the regulatory platform; obtaining a link stability confirmation result; querying the regulatory platform for the latest regulatory data timestamp already stored on the platform side to obtain the latest confirmation timestamp on the platform side; comparing the latest confirmation timestamp on the platform side with the timestamps of cached data units in SRAM Level 1 cache and eMMC Level 2 storage; identifying cached data units with timestamps later than the latest confirmation timestamp on the platform side as incremental supplementary reporting datasets; performing subsequent supplementary reporting scheduling only on incremental supplementary reporting datasets, skipping cached data units already confirmed to be stored on the platform side.

[0032] In one example, the data type of the read regulatory data is parsed, and the rapid acceleration event frame, attitude change event frame and geofence crossing record are classified as alarm-type regulatory data, while the positioning frame, attitude cycle frame and working condition frame are classified as status-type regulatory data. Alarm-related regulatory data is written to the high-priority alarm queue, and status-related regulatory data is written to the low-priority status queue.

[0033] In this example, a data type parsing subunit and a dual-queue writing subunit are set up inside the supplementary reporting scheduling engine. After reading the regulatory data from the SRAM level 1 cache or eMMC level 2 storage in chronological order, data type parsing is performed on each piece of regulatory data. The protocol processing unit first reads the data type identifier field, event flag field, or business category field in the header of the regulatory data, and classifies and identifies the read regulatory data in combination with the state parameter range, event trigger bit, and record source in the regulatory data payload. When the identification result shows that the current regulatory data belongs to a rapid acceleration event frame, attitude change event frame, or geofence boundary crossing record, the current regulatory data is identified as alarm-type regulatory data. The above data directly corresponds to changes in flight risk, breach of safety boundary, or abnormal flight status and has higher regulatory handling value. When the identification result shows that the current regulatory data belongs to a positioning frame, attitude period frame, or operating condition frame, the current regulatory data is identified as status-type regulatory data. The above data is mainly used to continuously describe the aircraft's position evolution, attitude change, and operating condition. In the supplementary reporting stage at the beginning of communication recovery, the urgency of real-time handling is lower than that of alarm-type regulatory data. The dual-queue writing subunit writes alarm-type regulatory data to the high-priority alarm queue and status-type regulatory data to the low-priority status queue according to a preset mapping relationship, maintaining the original time order within each queue during the writing process. After the queue writing is completed, the timestamp, sequence number, and historical supplementary report identifier attached to each piece of regulatory data are retained. This allows the supplementary report sending control unit to organize the transmission at a controlled rate lower than the real-time data transmission rate in subsequent stages, prioritizing the high-priority alarm queue over the low-priority status queue. This ensures that critical historical events such as rapid acceleration event frames, attitude change event frames, and geofence boundary crossing records are prioritized for back transmission after communication is restored, while avoiding a large number of positioning frames, attitude cycle frames, and operational status frames from consuming the newly restored link bandwidth in a short period of time.

[0034] Before sending the supplementary data packet to the regulatory platform, the process includes: performing a CRC32 check on each cached data unit read from the SRAM Level 1 cache or eMMC Level 2 storage, classifying the check results into two categories: successful and unsuccessful, to obtain an integrity verification result; based on the integrity verification result, marking the corresponding index entry in the file index of the unsuccessful cached data unit as corrupted and removing it from the current supplementary reporting scheduling queue to obtain a valid supplementary data set; attaching historical supplementary reporting identifiers to the cached data units in the valid supplementary data set, and sending the supplementary data packet to the regulatory platform in the order of high-priority alarm queue over low-priority status queue.

[0035] In one example, such as Figure 4The regulatory platform verifies each supplementary data packet, updates the supplementary reporting status flag in the eMMC secondary storage, and re-reports regulatory data with an unconfirmed status to the regulatory platform upon device power-on, including: S31, the monitoring platform performs CRC32 verification on each supplementary data packet and returns confirmation response information. Based on the timestamp and sequence number carried in the confirmation response information, the supplementary status flag of the corresponding index entry in the file index of eMMC secondary storage is updated to the confirmed status. S32, when the device is powered on again, scans the file index of the eMMC secondary storage and re-reports the regulatory data corresponding to the index entries whose supplementary reporting status is marked as unconfirmed to the regulatory platform.

[0036] In this example, the data monitoring module, file index management unit, and power-on recovery unit within the airborne monitoring equipment work together to complete the closed-loop processes for supplementary reporting confirmation and power-off resume transmission. During the supplementary reporting phase, the airborne monitoring equipment sends supplementary reporting data packets to the monitoring platform in ascending order of timestamps and in accordance with priority scheduling rules. Upon receiving each supplementary reporting data packet, the monitoring platform performs a packet-by-packet integrity verification of the CRC32 checksum carried in each packet. Only when the verification passes is a corresponding confirmation response message generated and sent back to the airborne monitoring equipment. The confirmation response message also carries the timestamp and sequence number of the corresponding supplementary reporting data packet, thereby enabling the airborne monitoring equipment to establish an accurate mapping relationship between the platform's confirmation result and the locally persistent backup data. After receiving the confirmation response, the airborne surveillance equipment retrieves the corresponding index entry in the file index area of ​​the eMMC secondary storage based on the timestamp and sequence number. It then updates the supplementary reporting status flag of the corresponding index entry from unconfirmed to confirmed. This process does not directly modify the surveillance data body already written to the data entity area; instead, it completes the supplementary reporting progress registration by updating the status field in the file index, thereby reducing the overhead of secondary writes and maintaining the continuity and stability of the data entity area. Since the timestamp reflects the generation time of the surveillance data, and the sequence number reflects the order of different data units within the same time interval, using a combination of timestamp and sequence number as the index positioning basis avoids positioning conflicts caused by relying solely on the time field, ensuring the determinism and traceability of status updates after package-by-package confirmation. After the above update, a file index structure with both "confirmed" and "unconfirmed" statuses is formed in the local eMMC secondary storage. The confirmed status corresponds to historical supplementary reporting data that has been successfully received and verified by the surveillance platform, while the unconfirmed status corresponds to historical surveillance data that has not yet been confirmed by the platform and still needs to be retained and awaits subsequent transmission. When the device is powered on again, the power-on recovery unit scans the file index of the eMMC secondary storage, identifies each index entry whose supplementary reporting status is still in the unconfirmed state, and uses these index entries to trace back and locate the corresponding regulatory data entities. The regulatory data corresponding to the unconfirmed index entries is then re-included in the supplementary reporting set and re-reported to the regulatory platform in ascending order of timestamps. Even if an abnormal power outage, momentary power failure, or system restart occurs during the blind zone or supplementary reporting phase, the supplementary reporting progress will not be lost due to the memory state being cleared, because the supplementary reporting progress is already stored in the file index of the eMMC secondary storage. After power-on, only scanning of the unconfirmed index entries is needed to resume the supplementary reporting process.To ensure that the transmission process after restoration does not crowd out the real-time service channel, the historical supplementary reporting and real-time monitoring data transmission process after power-on is coordinated. Under the premise that the real-time link is available, the current real-time monitoring data reporting is maintained first. Then, during the historical supplementary reporting transmission cycle, the unconfirmed status monitoring data is read from the eMMC secondary storage in ascending order of timestamp and sent to the monitoring platform until the unconfirmed status index entries are cleared.

[0037] In one example, the monitoring platform performs CRC32 verification on each supplementary data packet and returns an acknowledgment response. Based on the timestamp and sequence number carried in the acknowledgment response, the supplementary status flag of the corresponding index entry in the eMMC secondary storage file index is updated to the acknowledged status, including: Each received supplementary data packet undergoes a CRC32 check. After the CRC32 check passes, an acknowledgment response containing the timestamp and sequence number of the supplementary data packet is returned to the airborne surveillance equipment. Based on the timestamp and sequence number carried in the confirmation response information, locate the corresponding index entry in the file index of the eMMC secondary storage, and update the supplementary reporting status flag of the index entry from unconfirmed to confirmed.

[0038] In this example, after receiving the supplementary reporting data packet, the remote monitoring platform reads the historical supplementary reporting identifier, timestamp field, sequence number field, and CRC32 checksum carried in the packet, and performs integrity verification packet by packet according to the receiving order. Only when the CRC32 result recalculated by the remote monitoring platform based on the received byte stream matches the CRC32 checksum carried in the supplementary reporting data packet is the current supplementary reporting data packet deemed to have passed verification, and a corresponding confirmation response is generated and returned to the airborne monitoring equipment. The confirmation response retains the timestamp and sequence number of the current supplementary reporting data packet. This packet-by-packet verification and confirmation process ensures that each piece of historical monitoring data is independently verified, preventing local errors in batch transmission from affecting the overall supplementary reporting results. It also facilitates precise location and retransmission control of abnormal supplementary reporting data in the early stages of link recovery. After receiving the confirmation response, the airborne monitoring equipment's file index management unit performs an index search in the file index area of ​​the eMMC secondary storage based on the timestamp and sequence number carried in the confirmation response, and locates the target index entry from the set of index entries that corresponds one-to-one with the current supplementary reporting data packet. After location is completed, the already persistently saved regulatory data entities are not directly overwritten. Instead, only the supplementary reporting status flag in the target index entry is flipped, updating it from unconfirmed to confirmed. To ensure the uniqueness of index location, the timestamp is used to characterize the generation time of the regulatory data, and the sequence number is used to distinguish different regulatory data units generated consecutively within the same time neighborhood. Therefore, using the combination key of "timestamp + sequence number" can avoid matching ambiguities that occur when relying solely on the time field. After the above confirmation response processing, the file index in the eMMC secondary storage forms a supplementary reporting progress record structure with both confirmed and unconfirmed states. Data that has been correctly received by the regulatory platform and completed CRC32 verification will be promptly marked as confirmed, while data that has not yet received a valid confirmation response will remain in the unconfirmed state.

[0039] After the device is powered on again, the file index of the eMMC secondary storage is scanned to count the total number of index entries with the supplementary reporting status marked as unconfirmed. At the same time, the signal strength parameters of the current communication link are collected. When the total number of unconfirmed index entries is not less than 500 and the signal strength parameter is not lower than -90 dBm, the initial alternation scheduling ratio of the real-time monitoring data transmission cycle and the historical supplementary reporting data transmission cycle is set to 4:6. When the total number of unconfirmed index entries is not less than 500 and the signal strength parameter is lower than -90 dBm, the initial alternation scheduling ratio is set to 6:4. When the total number of unconfirmed index entries is less than 500, the initial alternation scheduling ratio is set to 7:3, thus obtaining the initial alternation scheduling configuration. The entry number threshold and alternation scheduling ratio are implementation parameters obtained by jointly adjusting the link capacity, real-time service occupancy rate and historical backlog scale, and can be adjusted according to the communication load capacity of the device model. According to the initial alternating scheduling configuration, the real-time monitoring data transmission cycle and the historical supplementary reporting data transmission cycle are alternately arranged according to the scheduling ratio. In each real-time monitoring data transmission cycle, the currently generated real-time monitoring data is sent first. In each historical supplementary reporting data transmission cycle, the monitoring data with unconfirmed status is read from the eMMC secondary storage in ascending order of timestamp and sent to the monitoring platform, resulting in an alternating transmission data stream. After each alternating scheduling cycle ends, the signal strength parameters of the communication link and the number of remaining unconfirmed status index entries in the eMMC secondary storage are re-collected. When the number of remaining unconfirmed status index entries decreases to below the preset low water level threshold, the proportion of the historical supplementary reporting data transmission cycle in the alternating scheduling ratio is reduced to 20%, and the proportion of the real-time monitoring data transmission cycle is increased to 80%. The preset low water level threshold is set to 10% of the total number of unconfirmed status index entries, resulting in an updated alternating scheduling configuration, which drives the next round of alternating transmission execution until the number of unconfirmed status index entries in the eMMC secondary storage is cleared.

[0040] Reference Figure 5 This embodiment provides an airborne surveillance data processing system, including: Data transfer module 1 is used to trigger the blind zone cache and write the regulatory data to the SRAM level 1 cache when both the main 4G link and the secondary 4G link are interrupted. When the amount of data in the SRAM level 1 cache reaches the water level threshold or the transfer cycle is reached, the regulatory data is transferred to the eMMC level 2 storage. The data supplementation module 2 is used to read regulatory data from SRAM level 1 cache or eMMC level 2 storage after the communication link is restored, and send supplementation data packets to the regulatory platform. Data monitoring module 3 is used to confirm the supplementary data packets one by one in the monitoring platform, update the supplementary status flag in the eMMC secondary storage, and re-report the monitoring data with the supplementary status flag as unconfirmed to the monitoring platform when the device is powered on again.

[0041] In this embodiment, the specific implementation of each unit in the above system embodiment is described in the above method embodiment, and will not be repeated here.

[0042] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, system, article, or method that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, system, article, or method. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, system, article, or method that includes that element.

[0043] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A method for processing airborne surveillance data, characterized in that, include: When both the primary 4G link and the secondary 4G link are interrupted, a blind zone cache is triggered, and monitoring data is written to the SRAM Level 1 cache. When the data volume in the SRAM Level 1 cache reaches the water level threshold or the transfer cycle is reached, the monitoring data is transferred to the eMMC Level 2 storage. Specifically, this includes: performing sliding window filtering on the first signal strength parameter of the primary 4G link to obtain a first signal strength filtered value; performing sliding window filtering on the second signal strength parameter of the secondary 4G link to obtain a second signal strength filtered value; determining whether the primary 4G link is interrupted based on the first signal strength filtered value and the first consecutive heartbeat timeout count of the primary 4G link; determining whether the secondary 4G link is interrupted based on the second signal strength filtered value and the second consecutive heartbeat timeout count of the secondary 4G link; when both the primary 4G link and the secondary 4G link are interrupted, a blind zone cache is triggered; after the blind zone cache is triggered, monitoring data is written to the SRAM Level 1 cache, and when the data volume in the SRAM Level 1 cache reaches the water level threshold or the transfer cycle is reached, the monitoring data is batch-appended and transferred to the eMMC Level 2 storage. After the communication link is restored, the monitoring data is read from the SRAM Level 1 cache or eMMC Level 2 storage, and a supplementary reporting data packet is sent to the monitoring platform. Specifically, this includes: after the communication link is restored, first reading the monitoring data from the SRAM Level 1 cache in ascending order of timestamp; when the SRAM Level 1 cache is empty, then reading the monitoring data from the eMMC Level 2 storage in ascending order of timestamp; scheduling the reading of the monitoring data according to the order of high-priority alarm queue over low-priority status queue, and sending supplementary reporting data packets to the monitoring platform at a controlled rate lower than the real-time data transmission rate; parsing the data type of the read monitoring data, classifying rapid acceleration event frames, attitude change event frames, and geofence boundary crossing records as alarm-type monitoring data, and classifying positioning frames, attitude cycle frames, and operating condition frames as status-type monitoring data; writing the alarm-type monitoring data into the high-priority alarm queue, and writing the status-type monitoring data into the low-priority status queue. The process involves: verifying each supplementary data packet in the monitoring platform, updating the supplementary reporting status flag in the eMMC secondary storage, and re-reporting the monitoring data with the supplementary reporting status flag set to unconfirmed when the device is powered on again. Specifically, this includes: performing CRC32 verification on each supplementary data packet in the monitoring platform and returning confirmation response information; updating the supplementary reporting status flag of the corresponding index entry in the file index of the eMMC secondary storage to confirmed status based on the timestamp and sequence number carried in the confirmation response information; and scanning the file index of the eMMC secondary storage when the device is powered on again, and re-reporting the monitoring data corresponding to the index entries with the supplementary reporting status flag set to unconfirmed to the monitoring platform.

2. The airborne surveillance data processing method according to claim 1, characterized in that, After the blind zone cache is triggered, the monitoring data is written to the SRAM Level 1 cache, and when the data volume in the SRAM Level 1 cache reaches the water level threshold or the transfer cycle is reached, the monitoring data is batch-appended and transferred to the eMMC Level 2 storage, including: After the blind zone cache is triggered, the monitoring data is appended with a BeiDou / GPS time stamp and a CRC32 checksum, and written to the SRAM level 1 cache in a circular queue. When the amount of data in the SRAM Level 1 cache reaches the water level threshold or the transfer cycle is reached, the monitoring data is transferred in batches to the eMMC Level 2 storage in an append-only manner.

3. The airborne surveillance data processing method according to claim 2, characterized in that, When the amount of data in the SRAM Level 1 cache reaches the water level threshold or the transfer cycle is reached, the monitoring data is transferred in batches to the eMMC Level 2 storage via append write, including: The amount of data in the SRAM L1 cache is compared with the water level threshold, and the transfer cycle is monitored simultaneously. When the amount of data reaches the water level threshold or the transfer cycle is reached, the regulatory data to be transferred is read from the SRAM level 1 cache, and the regulatory data is written to the eMMC level 2 storage in batches using an append write method.

4. The airborne surveillance data processing method according to claim 3, characterized in that, After the regulatory data is written to the eMMC secondary storage, the timestamp and sequence number of the regulatory data are extracted, and an index entry containing the timestamp, the sequence number and the supplementary reporting status flag is created for each piece of regulatory data in the file index of the eMMC secondary storage. The supplementary reporting status flag in the index entry is initialized to an unconfirmed state to obtain persistent backup data.

5. The airborne surveillance data processing method according to claim 1, characterized in that, The process of performing CRC32 verification on each of the supplementary data packets on the monitoring platform and returning confirmation response information, and updating the supplementary status flag of the corresponding index entry in the file index of the eMMC secondary storage to the confirmed status based on the timestamp and sequence number carried in the confirmation response information, includes: Each received supplementary data packet is subjected to CRC32 verification. After the CRC32 verification is successful, an acknowledgment response information carrying the timestamp and sequence number of the supplementary data packet is returned to the airborne monitoring equipment. Based on the timestamp and sequence number carried in the confirmation response information, the corresponding index entry is located in the file index of the eMMC secondary storage, and the supplementary reporting status flag of the index entry is updated from unconfirmed to confirmed.

6. An airborne surveillance data processing system, characterized in that, The steps for implementing the airborne surveillance data processing method according to any one of claims 1 to 5 include: The data transfer module is used to trigger the blind zone cache and write the monitoring data into the SRAM level 1 cache when both the main 4G link and the secondary 4G link are interrupted. When the amount of data in the SRAM level 1 cache reaches the water level threshold or the transfer cycle is reached, the monitoring data is transferred to the eMMC level 2 storage. The data supplementation module is used to read the regulatory data from the SRAM level 1 cache or eMMC level 2 storage after the communication link is restored, and send the supplementation data packet to the regulatory platform. The data monitoring module is used to confirm the supplementary data packets one by one in the monitoring platform, update the supplementary status flag in the eMMC secondary storage, and re-report the monitoring data with the supplementary status flag set to unconfirmed to the monitoring platform when the device is powered on again.

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