A wireless sensing and control system for an aircraft and a self-diagnosis method thereof

Abstract

The application discloses a wireless sensing monitoring and control system in an aircraft and a self-diagnosis method thereof. The system adopts a double-layer network architecture composed of a backbone network and an access network to solve the drawbacks of a traditional cable network. The system adopts a wireless self-organizing network, and is composed of a wireless sensor, a sampling and coding device and a data synthesizer by means of composite multiple access (FDMA+TDMA) and wireless communication technology based on LoRa. The system transmits data wirelessly except for power supply cables, has the functions of dynamic networking and fault diagnosis, improves safety and reliability, reduces weight and cost, enhances expandability, is suitable for missiles, rockets and the like, and provides a feasible scheme for cableless communication, and has a wide application prospect.

Description

Technical Field

[0001] This invention belongs to the field of aircraft measurement and control technology, specifically relating to a wireless sensing and measurement and control system for aircraft and its self-diagnosis method, applicable to scenarios of multi-type parameter acquisition, transmission and fault handling in various sections of an aircraft. Background Technology

[0002] With the development of measurement systems for large launch vehicles and missile weapons, there is a need to collect engineering telemetry parameters from various subsystems. Currently, mainstream platforms can measure hundreds to thousands of parameters per launch, and this number will continue to increase as the requirements for measurement precision become more stringent. Sensors are distributed throughout all stages and sections of the rocket. Existing rocket-borne measurement data integration systems employ a distributed acquisition and centralized integration approach, consisting of multiple remote acquisition and editing units and a data synthesizer (or central programmer). This traditional wired measurement system has many problems, such as difficulty in controlling the quality of the transmission medium, potential safety issues due to plug and wire losses, and poor scalability. Therefore, there is an urgent market demand for cableless transmission for rocket and missile measurement systems.

[0003] Currently, wireless sensing technology is theoretically mature and has been widely applied in various fields such as the Industrial Internet, smart homes, and smart cities, including warehousing and logistics management in enclosed environments similar to those of projectiles. This provides a theoretical foundation and technical reference for applying wireless sensing technology to projectile measurement systems. Meanwhile, the research and application of satellites have yielded numerous results in related wireless communication technologies, offering further insights for the cableless transmission of projectile measurement systems.

[0004] In existing technologies, mainstream rocket-borne measurement data integration systems adopt a wired architecture of "distributed acquisition and centralized integration," consisting of multiple sensors, acquisition nodes, aggregation nodes, wireless gateways, and data synthesizers. The principle is as follows: sensor acquisition units are distributed throughout the rocket, encoding and modulating the acquired status data before wirelessly transmitting it to the aggregation node. The aggregation node packages the data from multiple sensors and forwards it to the data synthesizer via the wireless gateway. The data synthesizer is responsible for receiving and processing the data acquired by the acquisition units. Wireless transmission is carried out using Time Division Multiple Access (TDMA). However, this traditional wired system has significant drawbacks: First, the cable network design of existing systems is relatively complex. Existing systems do not completely eliminate the rigid association between the type of transmitted information and the transmission medium. Therefore, when facing different types of information transmission needs, it is still necessary to design specific transmission media according to the information type, resulting in continued complexity in the design work and making it difficult to fundamentally reduce the complexity and workload of the cable network. The existing design fails to fully consider the comprehensive needs of the entire aircraft's electrical system. Based on its communication transmission protocol (e.g., TDMA only), it only implements cableless design for certain areas or functions, failing to achieve comprehensive cableless optimization, leaving the overall system with some complex cabling issues. Secondly, it has poor scalability: the existing system uses a single-layer wireless self-organizing network architecture, or has weak self-organizing capabilities. Therefore, when the aircraft needs to expand or reduce functionality, network entry and exit operations may be inconvenient, failing to achieve plug-and-play functionality and requiring complex reconfiguration and design, affecting the system's scalability and upgradeability. Thirdly, its safety and quality control capabilities are limited: the existing system lacks robust self-diagnostic technology, or its self-diagnostic functions can only detect some common faults, failing to comprehensively detect and warn of potential faults. Therefore, in the face of complex fault situations, it may be unable to detect and handle problems in a timely manner, leading to reduced system safety. Even if a fault can be detected, without an effective fault isolation and handling mechanism, the fault may spread and affect the entire system, increasing the difficulty of quality control and impacting the normal operation of the aircraft.

[0005] Therefore, the technical problems that this invention needs to solve include:

[0006] Design level: To address the problem of high complexity and difficulty in designing traditional cable networks, a cableless transmission method is adopted for optimization and improvement, which removes the hard association between the type of transmitted information and the transmission medium, thereby reducing the complexity of the cable network and the workload of design.

[0007] Expansion level: In response to the problems of traditional cable networks requiring custom design and poor scalability due to one-time molding, a wireless self-organizing network architecture is adopted for optimization and improvement. The invisible network replaces the physical network, and it is plug-and-play when entering and leaving the network, making it easy to expand and cut.

[0008] Safety aspects: To address the issues of poor safety (prone plug solder joints to detachment, cables to break easily) and difficulty in quality control of traditional cable networks, self-diagnostic technology is adopted for optimization and improvement, enabling automatic completion of fault location, fault warning, fault isolation, and fault handling. Summary of the Invention

[0009] In view of this, the purpose of this invention is to develop a wireless sensing and control system and its self-diagnostic method for use in aircraft to meet the measurement and control requirements in complex environments inside aircraft, so as to solve the inherent defects of traditional wired systems and improve measurement and control efficiency, scalability and security.

[0010] Firstly, this application provides a wireless sensing and telemetry control system for use in an aircraft. The system adopts a two-layer network architecture consisting of a backbone network and an access network. The backbone network adopts a star network structure, which includes a main data synthesizer, a backup data synthesizer, and a wireless data acquisition and editing unit. Each wireless data acquisition and editing unit communicates wirelessly with the main data synthesizer and the backup data synthesizer using FDMA multiple access communication to achieve high-speed and reliable global data transmission. The access network uses wireless sensor nodes connected in a star or mesh topology. Each wireless sensor node communicates with the wireless data acquisition and editing unit using a composite multiple access method combining TDMA and LoRa to achieve distributed acquisition of telemetry information and regional information acquisition and encoding.

[0011] In one possible implementation, the backbone network uses the 2.4GHz communication frequency band and the modulation scheme is GFSK; the network connection mode of the access network is configured through parameter binding and uses the 433 / 470MHz communication frequency band.

[0012] In one possible implementation, when the backbone network needs to add or remove wireless data acquisition nodes, the time slot management parameters of the primary data synthesizer or the backup data synthesizer are configured through parameter binding to achieve network reconstruction. The primary data synthesizer and the backup data synthesizer constitute a central node with a dual hot standby design. The primary data synthesizer and the backup data synthesizer switch based on network health status information to eliminate the risk of telemetry information loss caused by single point failure of the central node.

[0013] In one possible implementation, the wireless sensor includes a signal conversion and conditioning module circuit, a signal processing and transmission circuit; the signal conversion and conditioning module circuit uses hardware-based resistors, capacitors, and inductors to achieve compatibility with various signal specifications, adapting to analog signal inputs with various voltage amplitudes; the signal processing and transmission circuit adopts a unified specification design, has multiple input signal interface forms, and is arranged separately from the signal conversion and conditioning module circuit; the wireless sensor integrates a low-power control unit and a radio transmission power management unit to reduce power consumption.

[0014] In one possible implementation, the wireless data acquisition and editing unit includes a power module, a microcontroller, an SRAM, a wireless transceiver module 1, and a wireless transceiver module 2. The microcontroller is connected to the SRAM, wireless transceiver module 1, and wireless transceiver module 2 respectively, and is used for data processing, storage scheduling, and communication control. The wireless transceiver module 1 is interconnected with the wireless sensor via TDMA+LoRa multiple access and modulation. The wireless transceiver module 2 is interconnected with the data synthesizer via FDMA mechanism and GFSK modulation.

[0015] In one possible implementation, the wireless data synthesizer includes a power module, an FPGA, a DDR, an E2PROM, a wireless transceiver module I, a wireless transceiver module II, and a telemetry transmitter interface. The FPGA is connected to the DDR, E2PROM, wireless transceiver module I, wireless transceiver module II, and the telemetry transmitter interface, serving as the core for data processing and control. The wireless transceiver module I collects the intermediate layer frame format Frame i emitted by the multi-channel acquisition and editing unit via TDMA+FSK multiple access and modulation, and compiles the telemetry frame format according to the requirements of the missile-launch transmission frame format protocol, forming a PCM code stream signal. The telemetry transmitter interface is compatible with both onboard digital telemetry transmitters and traditional analog telemetry transmitters. The wireless transceiver module II, employing TDMA+FSK multiple access and modulation, serves as a redundant backup for the wireless transceiver module I, ensuring communication continuity.

[0016] Secondly, this application provides a self-diagnostic method for an in-flight wireless sensing and control system, including a fault location method, the steps of which include:

[0017] s1. Data Acquisition and Monitoring: Deploy sensors at key nodes within the aircraft to collect system operation data and communication parameters of communication nodes in real time, and transmit the collected data to the data synthesizer in real time.

[0018] s2. Feature Extraction and Analysis: The data synthesizer uses the embedded fault feature model to extract and analyze features from the collected data. When the real-time data matches the features in the fault feature model, it determines that a fault may exist. At the same time, it analyzes the correlation between data from different sensors through correlation analysis algorithms.

[0019] s3. Fault location: An algorithm combining rule-based reasoning and neural networks is used to quickly filter and judge data according to pre-set fault rules, and automatically identify fault modes and fault locations.

[0020] Thirdly, this application provides a self-diagnostic method for an in-flight wireless sensing and control system, including a fault early warning method, the steps of which include:

[0021] s1. Parameter threshold setting: Configure the threshold range for the monitoring parameters of the wireless sensing and control system inside the aircraft;

[0022] s2. Real-time monitoring and judgment: The system's operating parameters are collected through wireless sensors, and the collected real-time data is compared with a preset threshold range. When the real-time data exceeds the threshold range, an early warning is triggered.

[0023] s3. Trend Analysis and Forecasting: Continuously analyze the changing trends of monitoring data using time series analysis algorithms, predict the future trajectory of parameter changes, and issue early warning signals when a possible fault is predicted;

[0024] s4. Early Warning Classification: Based on the severity and scope of the fault, early warnings are divided into three levels: Level 1, Level 2, and Level 3.

[0025] Fourthly, this application provides a self-diagnostic method for an in-flight wireless sensing and control system, including a fault isolation method, the steps of which include:

[0026] s1. Intelligent switch control: Intelligent switches are deployed in the electrical equipment and communication nodes within the aircraft. When a fault is detected, the intelligent decision-making system of the data synthesizer sends a control command to the intelligent switch based on the fault location result, cutting off the electrical and communication connections between the faulty unit and other normal units, thereby achieving fault isolation.

[0027] s2. Communication Protocol Control: A software-defined networking-based communication protocol is adopted in the communication network. When a faulty node is identified, the network topology is reconfigured through the SDN controller to isolate the faulty node from the network and prevent the fault from spreading to other nodes.

[0028] Fifthly, this application provides a self-diagnostic method for an in-flight wireless sensing and control system, including a fault handling method, the steps of which include:

[0029] s1. Power-off handling: When a fault that can be resolved by power-off is detected, the power supply to the faulty unit is cut off. At the same time, the system automatically records the power-off time of the faulty unit and the corresponding fault information for subsequent analysis and processing.

[0030] s2. Hot Backup Replacement: When a device is configured with hot backup, the system automatically switches to the hot backup device to maintain normal system operation when a failure of the primary device is detected, and marks the failed primary device for subsequent repair or replacement.

[0031] The beneficial effects of this invention are:

[0032] I. Significantly reduce system complexity: Adopt a two-layer wireless architecture of backbone network and access network, replace traditional wired transmission with wireless communication, and completely eliminate the hard association between the type of transmitted information and the medium.

[0033] II. Enhanced System Scalability and Flexibility: Based on wireless self-organizing network technology, it supports dynamic node joining / leaving the network. When adding or removing sensors or data acquisition devices, configuration can be completed simply by setting parameters, without the need to re-lay cables, achieving flexible "plug-and-play" expansion. The backbone network's flexible networking capability can quickly adapt to the needs of aircraft mission adjustments, solving the problems of poor scalability and high customized design costs of traditional wired systems.

[0034] III. Enhancing Data Transmission Reliability and Anti-interference Capability: Utilizing FDMA+TDMA multiple access fusion combined with LoRa spread spectrum communication: The access network employs the 433 / 470MHz frequency band and LoRa technology, offering strong anti-interference capabilities and transmission distances sufficient for coverage within the cabin section; the backbone network uses the 2.4GHz frequency band and GFSK modulation, with a maximum code rate of 2Mbps, suitable for high-speed data transmission. A dual-hot-standby data synthesizer design effectively eliminates the technical risk of telemetry information loss due to single-point failure of the central node.

[0035] IV. Achieving Intelligent Full-Process Fault Handling: Integrating a Closed-Loop Self-Diagnosis Mechanism of "Location-Early Warning-Isolation-Handling": Potential faults can be identified in advance through rule-based reasoning and neural network fusion algorithms; Isolation strategies based on intelligent switches and SDN protocols, and hierarchical handling schemes, significantly improve the emergency response capabilities of aircraft. Attached Figure Description

[0036] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0037] Figure 1 This is a block diagram illustrating the principle of an existing aircraft measurement data integration system.

[0038] Figure 2 This is a network architecture diagram of the wireless sensing and control system of the present invention.

[0039] Figure 3 This is a schematic diagram of the power distribution method of the wireless sensing and control system of the present invention.

[0040] Figure 4 This is a power-on flowchart of the infinite sensing and control system of the present invention;

[0041] Figure 5 This is a schematic diagram of the FDMA principle of the present invention.

[0042] Figure 6 This is a schematic diagram of the TDMA principle of the present invention.

[0043] Figure 7This is a block diagram illustrating the principle of multiple access composite communication in this invention.

[0044] Figure 8 This is a block diagram illustrating the design principle of the wireless sensor of the present invention.

[0045] Figure 9 This is a block diagram of the wireless data acquisition module of the present invention.

[0046] Figure 10 This is a block diagram of the wireless data synthesizer module of the present invention. Detailed Implementation

[0047] Example 1

[0048] This embodiment provides a wireless sensing and telemetry control system for aircraft. The system adopts a two-layer network architecture consisting of a backbone network and an access network. The backbone network adopts a star network structure, which includes a main data synthesizer, a backup data synthesizer, and a wireless data acquisition and editing unit. Each wireless data acquisition and editing unit communicates wirelessly with the main data synthesizer and the backup data synthesizer using FDMA multiple access communication to achieve high-speed and reliable global data transmission. The access network uses wireless sensor nodes connected in a star or mesh topology. Each wireless sensor node communicates with the wireless data acquisition and editing unit using a composite multiple access method combining TDMA and LoRa to achieve distributed acquisition of telemetry information and regional information acquisition and encoding.

[0049] Existing aircraft measurement data integration systems employ a distributed acquisition and centralized integration approach. They consist of multiple acquisition and editing units and a data synthesizer (or central programmable controller). The acquisition and editing units are distributed across various sections of the rocket as needed, responsible for acquiring the measured parameters locally, encoding the acquired data, and transmitting it to the data synthesizer via serial ports. The data synthesizer is configured with several acquisition and editing unit interfaces and other peripheral interfaces, controlling the acquisition, transmission order, and encoding of all aircraft parameters, and forming a PCM (Programmable Module) information stream. The current architecture of the aircraft measurement data integration system is as follows: Figure 1 As shown:

[0050] The new generation measurement and synthesis system in this embodiment employs a two-level synthesis topology to complete the acquisition and synthesis of aircraft parameters. Specifically, the data acquisition and editing unit completes the acquisition and synthesis of parameters for its respective section, while the data synthesizer completes the synthesis of data from the acquisition and editing unit. This data synthesis method, which differs from the traditional model, increases the data synthesis capability from the traditional 1Mb / s to 2Mb / s to 10Mb / s.

[0051] Table 1 shows examples of common transmission service types and signal characteristics of aircraft measurement systems:

[0052] Table 1 Common Internal Business Types of Measurement Systems

[0053]

[0054]

[0055] The various physical quantities to be collected were summarized and categorized according to signal form, number of channels, and communication rate, and their data transmission rate and number of collection nodes were statistically analyzed, as shown in Table 2.

[0056] Table 2. Signal transmission characteristics of the physical quantities to be collected

[0057] Serial Number signal form Path Single-channel communication rate 1 Analog quantity No less than 32 routes 5kbps~25kbps 2 switch quantity No less than 8 routes 1kbps~10kbps 3 Synchronous digital quantity No less than 4 routes 250kbps~2Mbps 4 Asynchronous digital quantity No less than 4 routes 10kbps~38.4kbps

[0058] As can be seen from the statistical analysis in the table above, the single-channel communication rates of analog, digital, and asynchronous digital signals in the measurement system are mostly below 50kbps, which is considered low bit rate data transmission. However, there are many channels, and they often exist in a distributed multi-communication node manner. The single-channel communication rates of asynchronous digital signals are mostly above 200kbps, which is a relatively high bit rate. The image synchronization digital signal output by the image compressor can reach up to 2Mbps, but overall, the number of synchronous digital signals is still relatively small.

[0059] To meet the practical needs of the missile and rocket measurement system for business transmission, and to possess the technical advantages of providing high-speed and reliable data transmission services for the entire rocket and flexible networking, this embodiment adopts a cableless transmission system with a two-layer network structure consisting of a backbone network and an access network. The network architecture diagram is shown in Figure 2.

[0060] The backbone network in this embodiment consists of a primary data synthesizer, a backup data synthesizer, and wireless acquisition and editing units. It provides high-speed, reliable data transmission services globally, primarily handling the main and backup wireless data synthesis and wireless communication between the acquisition and editing units in each compartment (area). The backbone network adopts a star network structure. Each acquisition and editing unit communicates with the primary and backup synthesizers via FDMA (Fiber-Defined Multiple Access). Network runtime synchronization is managed by the primary synthesizer, and in the event of a primary unit failure, the backup synthesizer takes over.

[0061] Because the data transmission rate in the backbone network is relatively high, in order to meet the requirements of large communication bandwidth and avoid wireless communication interference with the access network, it is proposed to use the 2.4 GHz communication frequency band for link design, and the modulation scheme selected is GFSK, with a communication code rate of up to 2 Mbps.

[0062] The backbone network has flexible networking capabilities. Adding or removing nodes can be quickly reconfigured by configuring the time slot management parameters of the synthesizer through parameter binding. It is designed with a dual hot standby mode for the central node, and the switching mechanism is based on network health status information, which effectively eliminates the technical risk factor of telemetry information loss due to single point failure of the central node.

[0063] The access network in this embodiment includes wireless sensor nodes and a wireless data acquisition and encoding device, mainly performing distributed sensing edge and regional information acquisition and encoding functions for telemetry information. The sensor nodes and the wireless data acquisition and encoding device are connected in a star / mesh topology. The network mode can be configured through parameter setting, and the multiple access mode adopts a TDMA+LoRa composite access method, which effectively ensures both independent channel for system nodes and meets communication transmission distance requirements.

[0064] Due to the low data transmission rate in the access network, and to avoid wireless communication interference with the backbone network, it is proposed to use the 433 / 470MHz communication frequency band for link design, with a maximum communication code rate of over 200kbps.

[0065] In this embodiment, the power supply still needs to be designed using a wired method, such as... Figure 3 As shown. The reasons are as follows: First, wireless power transmission is inefficient and generally only suitable for low-power components, making it unsuitable for applications where onboard power is scarce. Second, in traditional measurement systems, data synthesizers and data acquisition units often use a 28V+ / 28V- dual-point dual-wire floating shell design, while sensors often use a +5V / +15V / -15V single-point single-wire floating shell design. This results in a limited number of cables and plugs, a relatively simple connection method, and a high degree of reliability. The power-on workflow of the wireless sensing and control system is as follows: Figure 4 As shown: The device first completes power-on and initialization, then attempts to establish a communication link. If the link establishment fails, it is re-established. After the link establishment is successful, data acquisition is carried out. At the same time, the system continuously monitors the status. If an abnormality is detected, fault location and fault handling are performed in sequence, and then the system returns to the system status monitoring stage to ensure the stable operation of the system.

[0066] This embodiment utilizes composite multiple access technology (FDMA+TDMA) and LoRa-based wireless communication technology to ensure efficient time and frequency resource management and high communication efficiency. FDMA, or Frequency Division Multiple Access, divides frequency band resources into carriers of different bandwidths in the frequency domain according to transmission requirements. These carriers are allocated to users within the network for individual use, enabling users to transmit data simultaneously on different frequencies—a process known as frequency division multiplexing. Within the access network's wireless communication operating frequency band, the transceiver's operating frequency is divided into several narrowband channels at certain frequency intervals. Each narrowband channel is allocated to a specific access node. Each node transmits data in its respective narrowband channel without time constraints, and the channels are independent and do not interfere with each other, effectively ensuring the real-time transmission of data from the access-end sensors. In narrowband channels, the channel bandwidth utilization is determined by the transmission rate of the node. When defining the narrowband width, the node with the highest code rate in the current access network is used as the standard. Although this allocation method may result in low bandwidth utilization for some lower code rate nodes, based on the previous analysis of the characteristics of the transmitted physical quantities in the measurement system, the information content of these sensors is generally relatively small. Therefore, although there is some waste, it still has a large system margin relative to the bandwidth of the selected transceiver device in the 410MHz~493MHz (BW=82MHz) frequency band. When dividing the narrowband channel, it is also necessary to ensure that adjacent channels have a certain guard bandwidth. The purpose of the guard bandwidth is to prevent spurious narrowband signal transmissions from falling into adjacent channels and causing cross-interference between channels.

[0067] The access network in this embodiment is constructed using the FDMA method, and its working principle is as follows: Figure 5 As shown in the figure, communication channels f1, f2, f3, and f4 respectively illustrate the spectrum allocation at a certain moment under the access layer FDMA multiple access conditions for "near-distance high-rate transmission node", "long-distance high-rate transmission node", "near-distance low-rate transmission node", and "long-distance low-rate transmission node".

[0068] TDMA stands for Time Division Multiple Access. It divides carriers on the same frequency band into frames at equal intervals in the time domain, and each frame period is further divided into several time slots with equal periods. Different time slots can be allocated to different users, enabling multiple users to transmit data sequentially on the same frequency without interference—that is, time division multiplexing. Guard intervals exist between frames and between time slots.

[0069] Figure 6The demonstration of data acquisition units 1-5 during TDMA multiple access communication with the data synthesizer shows that time is used as the standard for selecting the transmission target during communication. Within each time slot, the data synthesizer communicates with only one data acquisition unit, while other data acquisition units are in radio silence. As illustrated by the frequency band diagram of a certain time slot, this node can fully utilize the transmit / receive channel bandwidth (maximum bandwidth BW = 2MHz) during the communication period without considering other nodes, thus fully meeting the high-bit-rate transmission requirements of the backbone network. Although TDMA's real-time performance is not as good as FDMA, due to the 25ms frame period of traditional measurement systems and the fact that the number of data acquisition units in a primary carrier generally does not exceed four, we can still ensure that the transmission delay meets the telemetry standard requirements by reasonably configuring the time slot length. A certain guard interval must still be maintained between time slots. This is to prevent signal interference caused by time slot overlap due to timing errors, and also because the communication link contains energy storage components, and there is a certain delay in the start and stop of the transmitter power amplifier.

[0070] In this embodiment, the backbone network and access network communicate using an FDMA+TDMA multiple access fusion method. Within the same cabin segment, the access network, composed of sensors and data acquisition devices, uses TDMA multiple access, while the backbone network between cabin segments uses FDMA multiple access. This network can well adapt to the requirements of multi-source signal fusion acquisition, effectively reducing the impact of environmental influences within and between aircraft cabin segments on their respective signal acquisition. Its principle is as follows: Figure 7 As shown, in the backbone network, the data synthesizer and data acquisition unit adopt FDMA technology, allocating an independent center frequency (such as f1, f2...f) to each data acquisition unit within the operating bandwidth. n The system transmits data in parallel through different frequency channels, ensuring simultaneous communication between multiple data acquisition units. In the access network, the data acquisition units and sensors are based on TDMA technology, dividing time into multiple frame periods (frame period 1, frame period 2... frame period m), and each frame period is further subdivided into n time slots. Time slots are allocated to different sensors in sequence to collect data, avoiding signal conflicts. The data returned by the sensors includes frame headers, sensor numbers, types, measured physical quantities, status, and check bits, enabling orderly data transmission and reception and accurate identification, meeting the multi-parameter, high-reliability measurement and control requirements of aircraft.

[0071] The system in this embodiment adopts LoRa-based access layer wireless networking technology, which is suitable for the communication needs inside aircraft. Compared with short-range wireless communication technologies such as ZigBee, Bluetooth, and WiFi, LoRa uses linear spread spectrum modulation and demodulation technology, which can achieve ultra-long-distance transmission and meet the signal coverage requirements of multi-section and complex environments inside large launch vehicles and strategic missiles. At the same time, LoRa operates in the unlicensed frequency band below 1GHz, has an early start, mature development, and significant performance advantages. Its radio frequency chip has high integration and supports flexible parameter configuration; the star topology can carry tens of thousands of terminals, adopts "acquirer-sensor" one-to-many point communication, and avoids network paralysis caused by the failure of a single node; it has 6 spreading factors and 4 coding rates, combined with forward error correction (FEC) technology, which has strong anti-interference capabilities and can ensure data transmission reliability in complex electromagnetic environments, adapting to the low code rate and multi-node distributed acquisition needs of the access layer.

[0072] The measurement and control system in this embodiment has three types of communication terminal equipment: wireless sensors, wireless data acquisition and editing units, and wireless data synthesizers. Among them, wireless sensors, as the front-end devices for physical data acquisition and also the most numerous devices in the system, should be designed according to the following principles: a) The signal conversion and conditioning module circuit should be adaptable to various analog signal inputs with different voltage amplitudes. For various signal types, only one typical signal conversion form should be designed for each type, and compatibility with multiple specifications should be achieved as much as possible through hardware-based resistors, capacitors, and inductors. b) The signal processing and transmission circuits should be designed with unified specifications and should have a relatively rich variety of input signal interfaces. Furthermore, the signal conversion and conditioning module circuits should be designed separately during layout to avoid redundant development of circuits with the same form. c) Due to the introduction of wireless transmission, power consumption will inevitably increase compared to traditional wired transmission methods. Therefore, the sensor equipment should adopt a low-power design and radio transmission power control function.

[0073] The block diagram of wireless sensor design principle is as follows: Figure 8 As shown, its structure sequentially includes a data acquisition sensor, a signal conditioning circuit, an analog-to-digital converter (ADC), a microcontroller, and a wireless transceiver module. The data acquisition sensor detects the physical quantities to be measured inside the aircraft. The signal conditioning circuit performs preprocessing such as filtering and amplification on the acquired signals. The ADC converts the analog signals into digital signals. The microcontroller performs calculations and protocol encapsulation on the digital signals. Finally, the wireless transceiver module uses the 410MHz-493MHz frequency band and TDMA+LoRa multiple access and modulation technology to wirelessly transmit the processed data to the data acquisition and editing unit.

[0074] The wireless data acquisition unit is an intermediate link connecting the access network and the backbone network. Its specific functions are designed as follows: a) It can interconnect with wireless sensors via TDMA+LoRa to achieve one-to-many communication, complete the wireless acquisition of multiple sensor signals in a certain section or area of ​​the missile or rocket, and encode and generate intermediate layer frame format Frame i (i represents the data acquisition unit marked as 1, 2...n); b) It can interconnect with the data synthesizer via FDMA mechanism using GFSK modulation to complete the transmission of intermediate layer frame format Frame i.

[0075] The block diagram of the wireless data acquisition and editing device is as follows: Figure 9 As shown, its structure includes a power supply module, a microcontroller, SRAM, wireless transceiver module 1, and wireless transceiver module 2. The microcontroller is connected to the SRAM, wireless transceiver module 1, and wireless transceiver module 2 for data processing, storage scheduling, and communication control. Wireless transceiver module 1 interconnects with wireless sensors via TDMA+LoRa multiple access and modulation. Wireless transceiver module 2 interconnects with the data synthesizer via FDMA and GFSK modulation. During operation, the power supply provides power to all components. The microcontroller, as the core control unit, establishes connections with various sensors via wireless transceiver 1 (operating in the 410MHz-493MHz frequency band, using TDMA+LoRa technology), receives physical quantity data collected by the sensors, and temporarily stores it in the SRAM. Simultaneously, the microcontroller integrates and processes the data and transmits it to the data synthesizer via wireless transceiver 2 (operating in the 2.4GHz-2.5GHz frequency band, using FDMA+FSK technology), realizing data interaction between the access layer and the backbone network.

[0076] The wireless data synthesizer, as the top-level module of this system, is the central node of the backbone network. Its main functions are designed as follows: a) It is the central management device of the system, capable of managing system parameters, establishing and maintaining the network, locating faults, and providing feedback; b) It can collect intermediate layer frame format Frame i emitted by multiple acquisition and editing units via FDMA+FSK, and compile telemetry frame format according to the requirements of the missile-launch transmission frame format protocol, forming a PCM code stream signal; c) It has a synchronous digital PCM interface, and the interface should include three signal types: RS-422, 0~+5V TTL, and -5V~+5V, and be compatible with both onboard digital telemetry transmitters (synchronous RS-42 interface) and traditional analog telemetry transmitters (0~+5V TTL and -5V~+5V interfaces); d) As a key device of the wireless acquisition and transmission system, it is designed with dual channels and dual-machine hot standby to eliminate the significant impact of telemetry signal loss caused by single-point failure.

[0077] The block diagram of the wireless data synthesizer is as follows: Figure 10As shown, its structure includes a power module, FPGA, DDR, E2PROM, wireless transceiver module I, wireless transceiver module II, and telemetry transmitter interface. The FPGA is connected to the DDR, E2PROM, wireless transceiver module I, wireless transceiver module II, and telemetry transmitter interface, serving as the core for data processing and control. The wireless transceiver module I collects the intermediate layer frame format Frame i emitted by the multi-channel acquisition and editing unit through TDMA+FSK multiple access and modulation, and compiles the telemetry frame format according to the requirements of the missile-rocket transmission frame format protocol, forming a PCM code stream signal. The telemetry transmitter interface is compatible with both onboard digital telemetry transmitters and traditional analog telemetry transmitters. The wireless transceiver module II, using TDMA+FSK multiple access and modulation, serves as a redundant backup for the wireless transceiver module I, ensuring communication continuity.

[0078] Example 2

[0079] This embodiment provides a self-diagnostic method for an in-flight wireless sensing and telemetry control system, including a fault location method, a fault early warning method, a fault isolation method, and a fault handling method.

[0080] In this embodiment, the steps of the fault location method include:

[0081] s1. A large number of sensors are deployed at various key nodes within the aircraft to collect system operating data in real time, including but not limited to physical quantities such as temperature, pressure, humidity, vibration, overload, and heat flux, as well as communication parameters such as signal strength, transmission rate, and bit error rate of communication nodes. These sensors transmit the collected data to the data synthesizer in real time.

[0082] s2. Feature Extraction and Analysis: The data synthesizer utilizes an embedded fault feature model to extract and analyze features from the large amount of collected data. When real-time data shows features that match the fault feature model, a potential fault is identified. Simultaneously, correlation analysis algorithms are used to analyze the relationships between data from different sensors to more accurately locate the fault source.

[0083] s3. Fault Location: A fault location algorithm combining rule-based reasoning and neural networks is employed. Based on pre-defined fault rules, data is rapidly filtered and judged; fault modes and fault locations are automatically identified. This combination improves the accuracy and efficiency of fault location.

[0084] In this embodiment, the steps of the fault early warning method include:

[0085] s1. Parameter threshold setting: Configure the threshold range for the monitoring parameters of the wireless sensing and telemetry system inside the aircraft; the threshold setting can be determined based on the aircraft's design requirements, historical operating data, and expert experience.

[0086] s2. Real-time monitoring and judgment: The system's operating parameters are collected through wireless sensors, and the collected real-time data is compared with a preset threshold range. When the real-time data exceeds the threshold range, an early warning is triggered.

[0087] S3. Trend Analysis and Forecasting: Time series analysis algorithms are used to analyze the changing trends of monitoring data and predict potential future faults. Taking temperature parameters as an example, trend analysis of temperature data can predict whether equipment will malfunction due to overheating. When a potential fault is predicted, an early warning signal is issued.

[0088] s4. Early Warning Classification: Based on the severity and scope of the fault, early warnings are divided into different levels: Level 1 Early Warning (serious fault, affecting aircraft safety), Level 2 Early Warning (general fault, affecting some system functions), and Level 3 Early Warning (minor fault, with little impact on the system). The fault mode and fault code mapping are shown in Table 3.

[0089] Table 3 Mapping Relationship between Fault Categories and Fault Modes

[0090]

[0091] In this embodiment, the steps of the fault isolation method include:

[0092] s1. Intelligent switch control: Intelligent switches are installed on various electrical devices and communication nodes within the aircraft. When a fault is detected, the intelligent decision-making system on the data synthesizer sends control commands to the intelligent switches based on the fault location results, cutting off the electrical and communication connections between the faulty unit and other normal units, thereby achieving fault isolation.

[0093] s2. Communication Protocol Control: In the communication network, a communication protocol based on Software-Defined Networking (SDN) is adopted. When a faulty node is detected, the network topology is reconfigured through the SDN controller to isolate the faulty node from the network and prevent the fault from spreading to other nodes.

[0094] In this embodiment, the steps of the fault handling method include:

[0095] s1. Power outage handling: For some faults that can be resolved by power outage, such as short circuit faults and electrical overload faults, the power supply to the faulty unit is cut off. During the power outage process, the system will record the power outage time and fault information for subsequent analysis and processing.

[0096] s2. Hot Backup Replacement: For core critical equipment (affecting aircraft safety), a hot backup design is adopted. When a failure is detected in the primary equipment, the system automatically switches to the hot backup equipment to ensure normal system operation. Simultaneously, the system marks the failed primary equipment for subsequent repair or replacement.

[0097] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various modifications and variations; any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the protection scope of the present invention.

Claims

1. A wireless sensing and control system for use in aircraft, characterized in that... The system adopts a two-layer network architecture consisting of a backbone network and an access network. The backbone network adopts a star network structure, which includes a main data synthesizer, a backup data synthesizer, and a wireless data acquisition and editing unit. Each wireless data acquisition and editing unit communicates wirelessly with the main data synthesizer and the backup data synthesizer using FDMA multiple access communication to achieve high-speed and reliable data transmission globally. The access network uses wireless sensor nodes connected in a star or mesh topology; each wireless sensor node and the wireless data acquisition unit uses a composite multiple access method combining TDMA and LoRa to achieve distributed acquisition of telemetry information and regional information acquisition and encoding.

2. The wireless sensing and control system for aircraft as described in claim 1, characterized in that... The backbone network uses the 2.4GHz communication frequency band and the modulation scheme is GFSK; the network connection mode of the access network is configured through parameter loading and uses the 433 / 470MHz communication frequency band.

3. The wireless sensing and control system for aircraft as described in claim 1, characterized in that... When the backbone network needs to add or remove wireless data acquisition nodes, the time slot management parameters of the primary data synthesizer or the backup data synthesizer are configured through parameter binding to achieve network reconstruction. The primary data synthesizer and the backup data synthesizer constitute a central node with a dual hot standby design. The primary data synthesizer and the backup data synthesizer switch based on network health status information to eliminate the risk of telemetry information loss caused by single point failure of the central node.

4. The wireless sensing and control system for aircraft as described in claim 1, characterized in that: The wireless sensor includes a signal conversion and conditioning module circuit, a signal processing and transmission circuit; The signal conversion and conditioning module circuit achieves compatibility with various signal specifications through hardware-based resistors, capacitors, and inductors to adapt to analog signal inputs with various voltage amplitudes. The signal processing and transmission circuit adopts a unified specification design, has multiple input signal interface forms, and is arranged separately from the signal conversion and conditioning module circuit. The wireless sensor integrates a low-power control unit and a radio transmission power management unit to reduce power consumption.

5. The wireless sensing and control system for an aircraft as described in claim 1, characterized in that: The wireless data acquisition and editing unit includes a power module, a microcontroller, an SRAM, a wireless transceiver module 1, and a wireless transceiver module 2. The microcontroller is connected to the SRAM, wireless transceiver module 1, and wireless transceiver module 2 for data processing, storage scheduling, and communication control. The wireless transceiver module 1 is interconnected with the wireless sensor via TDMA+LoRa multiple access and modulation. The wireless transceiver module 2 is interconnected with the data synthesizer via FDMA and GFSK modulation.

6. The wireless sensing and control system for aircraft as described in claim 1, characterized in that: The wireless data synthesizer includes a power module, an FPGA, a DDR, an E2PROM, a wireless transceiver module I, a wireless transceiver module II, and a telemetry transmitter interface; the FPGA is connected to the DDR, E2PROM, wireless transceiver module I, wireless transceiver module II, and the telemetry transmitter interface respectively, and serves as the core for data processing and control; The wireless transceiver module I collects the intermediate layer frame format Frame i sent by the multi-channel acquisition and editing unit through TDMA+FSK multiple access mode, and compiles the telemetry frame format according to the requirements of the missile transmission frame format protocol, and forms a PCM code stream signal; the wireless transceiver module II adopts TDMA+FSK multiple access mode as a redundant backup of the wireless transceiver module I to ensure communication continuity. The telemetry transmitter interface is compatible with both rocket-borne digital telemetry transmitters and traditional analog telemetry transmitters.

7. A self-diagnostic method for an in-flight wireless sensing and control system, characterized in that, The fault location method includes the following steps: s1. Data Acquisition and Monitoring: Deploy sensors at key nodes within the aircraft to collect system operation data and communication parameters of communication nodes in real time, and transmit the collected data to the data synthesizer in real time. s2. Feature Extraction and Analysis: The data synthesizer uses the embedded fault feature model to extract and analyze features from the collected data. When the real-time data matches the features in the fault feature model, it determines that a fault may exist. At the same time, it analyzes the correlation between data from different sensors through correlation analysis algorithms. s3. Fault location: An algorithm combining rule-based reasoning and neural networks is used to quickly filter and judge data according to pre-set fault rules, and automatically identify fault modes and fault locations.

8. A self-diagnostic method for an in-flight wireless sensing and control system, characterized in that, This includes a fault early warning method, comprising the following steps: s1. Parameter threshold setting: Configure the threshold range for the monitoring parameters of the wireless sensing and control system inside the aircraft; s2. Real-time monitoring and judgment: The system's operating parameters are collected through wireless sensors, and the collected real-time data is compared with a preset threshold range. When the real-time data exceeds the threshold range, an early warning is triggered. s3. Trend Analysis and Forecasting: Continuously analyze the changing trends of monitoring data using time series analysis algorithms, predict the future trajectory of parameter changes, and issue early warning signals when a possible fault is predicted; s4. Early Warning Classification: Based on the severity and scope of the fault, early warnings are divided into three levels: Level 1, Level 2, and Level 3.

9. A self-diagnostic method for an in-flight wireless sensing and control system, characterized in that, The fault isolation method includes the following steps: s1. Intelligent switch control: Intelligent switches are deployed in the electrical equipment and communication nodes within the aircraft. When a fault is detected, the intelligent decision-making system of the data synthesizer sends a control command to the intelligent switch based on the fault location result, cutting off the electrical and communication connections between the faulty unit and other normal units, thereby achieving fault isolation. s2. Communication Protocol Control: A software-defined networking-based communication protocol is adopted in the communication network. When a faulty node is identified, the network topology is reconfigured through the SDN controller to isolate the faulty node from the network and prevent the fault from spreading to other nodes.

10. A self-diagnostic method for a wireless sensing and telemetry control system inside an aircraft, characterized in that, This includes troubleshooting methods, comprising the following steps: s1. Power-off handling: When a fault that can be resolved by power-off is detected, the power supply to the faulty unit is cut off. At the same time, the system automatically records the power-off time of the faulty unit and the corresponding fault information for subsequent analysis and processing. s2. Hot Backup Replacement: When a device is configured with hot backup, the system automatically switches to the hot backup device to maintain normal system operation when a failure of the primary device is detected, and marks the failed primary device for subsequent repair or replacement.

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