An airborne data bus optical link reliable control method based on a multi-mode PON

Abstract

This invention discloses a reliable control method for airborne data bus optical links based on multimode PON. First, a dual-channel OLT module simultaneously sends a terminal data transmission request query command to a designated bus terminal interface on two bus optical connection links. All bus terminal interfaces utilize dual-channel ONU modules, receiving bus data signals simultaneously on both channels. The designated bus terminal interface responds to the terminal data transmission request query command in real time using a determined link of the dual-channel ONU module, and sends the bus data signal it needs to transmit to the line controller on that determined link. The bus controller receives the bus data signal on the link determined by the terminal and forwards the terminal data signal in real time on both bus links. All bus terminal interfaces utilize dual-channel ONU modules, receiving bus data signals simultaneously on both channels, thus achieving deterministic transmission, redundant transmission, and redundant reception of signals transmitted by the bus terminal interfaces.

Description

Technical Field

[0001] This invention belongs to the field of communication technology, and more specifically, relates to a reliable control method for an airborne data bus optical link based on multimode PON. Background Technology

[0002] Airborne data bus is a crucial supporting technology for the integrated design and application of airborne systems in the aerospace field. The airborne data bus system is responsible for the efficient interconnection of system devices and the transmission and control of application data within integrated airborne systems. The architecture of the airborne data bus system provides system connection solutions for bus controller devices and bus remote terminal devices. The airborne data bus system adopts centralized control and management, and is required to have reliable operation management and data communication control capabilities.

[0003] The application of EPON optical link technology has greatly improved the design technology and system capabilities of airborne data buses. Currently, airborne data buses built using EPON optical links typically employ single-mode optoelectronic transceiver modules to achieve the optical link connection between the airborne bus controller and terminal equipment. However, single-mode optoelectronic transceiver modules suffer from drawbacks such as large module size and high power consumption, which prevents the miniaturization of the interface product design for the bus interface between the airborne bus controller and terminal equipment, hindering the widespread adoption of this technology. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a reliable control method for airborne data bus optical links based on multimode PON. It utilizes multimode EPON optical link technology to achieve miniaturized design of system equipment data bus interfaces in high-speed, high-reliability airborne data bus system architecture applications, and adopts a redundancy control mechanism to improve the determinism and reliability of network system operation management and data system transmission.

[0005] To achieve the above-mentioned objectives, this invention provides a reliable control method for an airborne data bus optical link based on multimode PON, characterized by comprising the following steps:

[0006] (1) Bus initialization;

[0007] The airborne data bus optical link reliable control system based on multimode PON is referred to as the control system. Power on the control system, initialize the first bus controller and the second bus controller to enable the data receiving function, and start the internal bus cycle timer.

[0008] (2) Redundancy control;

[0009] The first bus controller listens to the bus link signal through its optical network unit (ONU) interface. If it does not listen to a valid bus cycle control command within a predetermined N consecutive bus cycles, it determines that the bus control right is idle and then periodically sends bus cycle control commands through the optical line terminal (OLT) interface to obtain bus control right; where N is an integer greater than or equal to 2.

[0010] The second bus controller receives bus cycle control commands from the first bus controller via its ONU interface. When it detects that the first bus controller has gained control, it sets itself as a backup controller. Then, the second bus controller continuously monitors the bus cycle control commands sent by the first bus controller. If it does not receive the command within a predetermined M bus cycles, it determines that the first bus controller has failed and confirms the failure through interrupt reporting and discrete data lines. When the confirmation result is true, the second bus controller immediately sends a bus cycle control command via its OLT interface to take over bus control. Here, M is an integer greater than or equal to 2.

[0011] (3) Bus terminal operation management;

[0012] (3.1) The bus controller that has acquired control is used as the master bus controller. According to the bus cycle and based on the pre-configured bus terminal valid address table, the status query command is sent to each bus terminal address in sequence through the dual OLT interface.

[0013] (3.2) The bus terminal receives the query command through its dual ONU interface and parses the query command; then it compares whether the command address in the query command matches its own address. If the command address matches its own address, it proceeds to step (3.3); otherwise, it proceeds to step (3.4).

[0014] (3.3) The bus terminal sends online response data to the main bus controller through the ONU interface. After receiving the online response data, the main bus controller adds the address of the bus terminal to the bus online terminal control table. Subsequently, the main bus controller organizes the bus terminal to perform bus data communication according to the bus cycle based on the bus online terminal control table. The communication process is as follows:

[0015] The main bus controller sends data transmission query commands to the bus terminal through the OLT interface in address order. If the bus terminal has bus data to be transmitted at this time, it responds to the data transmission query command and sends the bus data to the main bus controller. The main bus controller performs integrity verification on the received bus data. If the verification passes, it sends a data reception confirmation command to the bus terminal. If the verification fails, it sends a reception failure command to the bus terminal and marks the data to be transmitted as pending retransmission.

[0016] The main bus controller dynamically monitors the communication status of online terminals. When the main bus controller queries the bus terminal again in a subsequent bus cycle, the bus terminal prioritizes sending data marked as pending retransmission. If a bus terminal fails to send data for K consecutive times, it is deleted from the online control table and re-queried and registered. Finally, the main bus controller broadcasts the confirmed bus data to the bus link through the dual OLT interface. All online bus terminals on the bus link receive bus data through their dual ONU interfaces.

[0017] (3.4) The bus terminal ignores the query command, does not send online response data, and does not participate in the reliable data communication organized by the main bus controller;

[0018] (3.5) During the bus operation, the backup bus controller continuously executes the redundancy control logic defined in step (2), that is: it listens for the bus cycle control command issued by the main bus controller through its ONU interface. If the command is not received within a predetermined M bus cycles, the main bus controller is determined to be faulty and is jointly confirmed by interrupt reporting and discrete data lines. When the confirmation result is true, the backup bus controller is immediately upgraded to a new main bus controller, takes over the bus control, and starts to execute the bus terminal operation management process from step (3.1).

[0019] The objective of this invention is achieved as follows:

[0020] This invention relates to a reliable control method for airborne data bus optical links based on multimode PON. The main bus controller acts as the centralized scheduling core. According to the bus cycle and based on the pre-configured terminal address table, it sequentially sends status query commands to each bus terminal address through dual OLT interfaces. The bus terminal receives the commands through dual ONU interfaces and only sends online response data to the main bus controller through the ONU interface to complete the registration when the command address matches its own address.

[0021] During the data communication phase, the main bus controller polls each online terminal in address order according to the online terminal control table, sending a query command via the dual-channel OLT interface. Only the queried terminal will respond to the command and transmit the data to be sent to the main bus controller via its ONU interface. After verifying and confirming the received data, the main bus controller broadcasts the data to the bus link via the dual-channel OLT interface.

[0022] During this process, all bus terminals (regardless of whether they are polled) simultaneously listen to and receive broadcast data on the bus through their dual ONU interfaces, achieving redundancy in data reception. Simultaneously, the redundancy control mechanism of the dual bus controllers ensures seamless switching of system control in the event of a master controller failure.

[0023] Meanwhile, the airborne data bus optical link reliability control method based on multimode PON of the present invention also has the following beneficial effects:

[0024] (1) This invention is an innovative design technology in the field of airborne data bus and network communication system applications, featuring a simple bus interface link structure and reliable management. This method can be widely applied to the design of high-performance airborne data bus systems in manned aircraft, unmanned aircraft, and other fields, meeting the needs of integrated design and application of high-performance airborne systems.

[0025] (2) This method adopts multimode EPON optical link technology to realize the miniaturized design of the airborne data bus equipment interface, effectively reducing the size of the optoelectronic transceiver module and reducing the module power consumption, thus meeting the miniaturized design requirements of the bus interface products of the airborne bus controller and terminal equipment. Through the redundancy control scheme of the bus data transmission link, the airborne data bus system can achieve centralized control management, reliable operation, and reliable control of data communication.

[0026] (3) In view of the size and power consumption problems of the separate single-mode optoelectronic transceiver module used in the bus interface of the airborne bus controller and the terminal equipment, the present invention utilizes multimode EPON optical link technology and performs integrated design to realize the dual-path combination of optoelectronic transceiver module, which effectively reduces the size of optoelectronic transceiver module and reduces module power consumption.

[0027] (4) While effectively reducing the size and power consumption of the optoelectronic transceiver module, this invention provides technical conditions for the management redundancy design of the airborne data bus system architecture and the redundant link connection control for data transmission between bus system devices such as bus controller devices and bus remote terminals. A reliable control method for airborne data bus optical links based on multimode EPON can support centralized control and management of airborne data bus systems, meeting the design requirements for reliable operation management and reliable communication control of airborne data bus systems.

[0028] (5) Enhanced system fault tolerance and seamless switching capability: This invention achieves rapid fault detection and seamless switching of the main controller through the dynamic redundancy control mechanism of the dual-bus controller. When the main controller fails, the backup controller can take over control in a very short time (such as several millisecond-level bus cycles) and restart the terminal management process, thereby ensuring the continuous and reliable operation of the bus system under the condition of single-point failure of the controller. This mechanism significantly improves the availability and task continuity of the entire airborne bus system.

[0029] (6) Support for deterministic real-time communication scheduling: This invention adopts a centralized scheduling strategy based on address polling, with the main controller uniformly allocating bus time slots, effectively avoiding data conflicts and channel contention between terminals, and ensuring the determinism and low latency of bus communication. By organizing terminal registration, querying, and data broadcasting sequentially within each bus cycle, the system can achieve timing guarantees for critical data transmission, meeting the stringent requirements of avionics systems for real-time performance and predictability. Attached Figure Description

[0030] Figure 1 This is a diagram of the reliable control system architecture for an airborne data bus optical link based on multimode PON.

[0031] Figure 2 This is a flowchart of the airborne data bus optical link reliability control method based on multimode PON of the present invention;

[0032] Figure 3 This is a flowchart of the bus terminal operation and management process;

[0033] Figure 4 This is a flowchart of reliable bus data communication. Detailed Implementation

[0034] The specific embodiments of the present invention will now be described with reference to the accompanying drawings to enable those skilled in the art to better understand the invention. It should be particularly noted that in the following description, detailed descriptions of known functions and designs that might obscure the main content of the invention will be omitted here.

[0035] Example

[0036] In this embodiment, as Figure 1 As shown, the PON (Passive Optical Network) architecture includes bus controller 1, bus controller 2, multiple bus terminals, multimode optical cables, and multimode optical splitters. Bus controller 1 and bus controller 2 have two redundant OLT (Optical Link Terminal) bus interfaces and two redundant ONU (Optical Network Unit) bus interfaces; the bus terminals have two redundant ONU (Optical Network Unit) bus interfaces; the multimode optical cables and multimode optical splitters constitute two redundant optical signal transmission medium channels. The bus topology and structure are as follows. Figure 1 As shown, it possesses the following main characteristics:

[0037] 1) Multimode single-fiber bidirectional burst optical transmission.

[0038] 2) Dual-redundant burst optical bus architecture, dual-redundant bus controller and redundancy control mechanism.

[0039] An airborne data bus architecture with dual-redundant topology was constructed using a small multimode dual-path OLT module and a multimode dual-path ONU module with optimized dual-redundant optical connection links. Based on the dual-redundant topology airborne data bus architecture, reliable operation management and reliable communication control of the airborne data bus system can be dynamically realized.

[0040] In the reliable control method described in this invention, the design of the values ​​of key reliability parameters N, M, and K follows the principle of combining high reliability and real-time performance of airborne systems:

[0041] Parameter N (number of bus control idle determination cycles): The value must consider both the speed of system initialization and the robustness against transient disturbances. If N=1, the system is too sensitive to single instruction loss and is prone to incorrect control contention due to transient disturbances; if N≥4, the system response is too slow, prolonging the "vacuum period" of the bus without a master. Simulation and experimental verification show that N=3 can effectively filter transient disturbances in most operating conditions and achieve rapid takeover when the master controller fails (e.g., only 6ms in a 2ms cycle), representing the best balance between reliability and latency. Therefore, in this invention, the preferred value of N is an integer greater than or equal to 2, and more preferably 3.

[0042] Parameter M (Number of Master Controller Failure Judgment Cycles): This parameter serves as the criterion for the backup controller to take over the bus, and its design logic is consistent with N. M=3 ensures that the takeover decision has sufficient confidence, avoiding "dual master" conflicts caused by transient noise in the link. At the same time, the probability of false switching is further reduced through the joint confirmation mechanism of interrupt reporting and discrete data lines. The value of M is also an integer greater than or equal to 2, preferably 3.

[0043] Parameter K (Number of retry attempts for terminal communication failure): This parameter is used to strike a balance between communication efficiency and fault isolation speed. If K=1, terminals are easily kicked out frequently due to instantaneous link quality fluctuations, increasing system overhead; if K≥4, faulty terminals will occupy bus resources for a long time, affecting overall scheduling efficiency. K=3 is a verified and effective compromise, giving terminals enough retry opportunities to overcome instantaneous anomalies while also isolating persistently faulty terminals in a timely manner. The value of K is designed to be an integer greater than or equal to 2, preferably 3.

[0044] Below we combine Figure 1 As shown, a detailed description of the airborne data bus optical link reliability control method based on multimode PON of the present invention is provided, such as... Figure 2 As shown, the specific steps include:

[0045] (1) Bus initialization;

[0046] The airborne data bus optical link reliable control system based on multimode PON is referred to as the control system. Power on the control system, initialize the first bus controller and the second bus controller to enable the data receiving function, and start the internal bus cycle timer.

[0047] (2) Redundancy control;

[0048] The first bus controller listens to the bus link signal through its optical network unit (ONU) interface. If it does not hear a valid bus cycle control command within a predetermined three consecutive bus cycles (the value N=3 can effectively filter transient interference and achieve fast response while ensuring system robustness), it determines that the bus control right is idle and then periodically sends bus cycle control commands through the optical line terminal (OLT) interface to obtain bus control right. In this embodiment, the bus cycle is predefined as 2ms.

[0049] The second bus controller receives bus cycle control commands from the first bus controller through its ONU interface. When it senses that the first bus controller has gained control, it sets itself as a backup controller. Then, the second bus controller continuously monitors the bus cycle control commands sent by the first bus controller. If it does not receive the command within three consecutive predetermined bus cycles, it determines that the first bus controller has failed and confirms it through interrupt reporting and discrete data lines. When the confirmation result is true, the second bus controller immediately sends a bus cycle control command through its OLT interface and takes over bus control.

[0050] (3) Bus terminal operation management, such as Figure 3 As shown;

[0051] (3.1) The bus controller that has acquired control is used as the master bus controller. According to the bus cycle and based on the pre-configured bus terminal valid address table, the status query command is sent to each bus terminal address in sequence through the dual OLT interface.

[0052] In this embodiment, the bus controller that has acquired bus control acts as the master bus controller. According to the bus cycle (2ms in this example), based on the pre-configured bus terminal valid address table (capacity of 64), it sends a status query command to a target terminal address in unicast form and in descending order of address at the beginning of each bus cycle through the dual-channel OLT interface. After completing one round of query, the process is repeated.

[0053] (3.2) The bus terminal receives the query command through its dual ONU interface and parses the query command; then it compares whether the command address in the query command matches its own address. If the command address matches its own address, it proceeds to step (3.3); otherwise, it proceeds to step (3.4).

[0054] (3.3) The bus terminal sends online response data to the main bus controller via the ONU interface. After receiving the online response data, the main bus controller adds the address of the bus terminal to the bus online terminal control table. Subsequently, the main bus controller, according to the bus online terminal control table, polls sequentially in each bus cycle according to the address order of the online terminals to organize bus data communication. The specific process is as follows: Figure 4 As shown:

[0055] The main bus controller sends data transmission query commands to the bus terminal through the OLT interface in address order. If the bus terminal has bus data to be transmitted at this time, it responds to the data transmission query command and sends the bus data to the main bus controller. The main bus controller performs integrity verification on the received bus data. If the verification passes, it sends a data reception confirmation command to the bus terminal. If the verification fails, it sends a reception failure command to the bus terminal and marks the data to be transmitted as pending retransmission.

[0056] The main bus controller dynamically monitors the communication status of online terminals. When the main bus controller queries the bus terminal again in a subsequent bus cycle, the bus terminal prioritizes sending data marked as pending retransmission. If a bus terminal fails to send data three times in a row (the value K=3 achieves the best balance between communication efficiency and fault isolation), it is deleted from the online control table and re-queried and registered. Finally, the main bus controller broadcasts the confirmed bus data to the bus link through the dual OLT interface. All online bus terminals on the bus link receive the bus data through their dual ONU interfaces.

[0057] (3.4) The bus terminal ignores the query command, does not send online response data, and does not participate in the reliable data communication organized by the main bus controller;

[0058] (3.5) During the bus operation, the backup bus controller continuously executes the redundancy control logic defined in step (2), that is: it listens for the bus cycle control command issued by the main bus controller through its ONU interface. If the command is not received within three consecutive predetermined bus cycles, the main bus controller is determined to be faulty and is jointly confirmed by interrupt reporting and discrete data lines. When the confirmation result is true, the backup bus controller is immediately upgraded to a new main bus controller, takes over the bus control, and starts to execute the bus terminal operation management process from step (3.1).

[0059] In summary, the present invention achieves the following key effects:

[0060] Dual-controller redundancy control: When the main controller fails, the backup controller can complete the detection and takeover within 6ms (3 bus cycles), demonstrating the system's high fault tolerance.

[0061] Deterministic communication scheduling: Through centralized control of address polling, data conflicts are avoided, ensuring the determinism and real-time performance of bus access, with a single-hop forwarding latency of less than 14μs.

[0062] Miniaturization and low power consumption: The use of multimode optical modules significantly reduces module size and power consumption compared to traditional single-mode solutions, meeting the miniaturization requirements of airborne equipment.

[0063] Therefore, the airborne data bus optical link reliability control method based on multimode PON proposed in this invention significantly reduces module size and power consumption while ensuring high-speed transmission by using multimode optical fiber and integrated multimode optical transceiver module.

[0064] This invention further integrates a dual-redundant control mechanism and a bidirectional burst transmission architecture, enhancing the system's real-time performance and fault tolerance. While improving the reliability of the bus system, it provides a practical technical path for the miniaturization, lightweight design, and integrated application of airborne equipment, and has significant engineering promotion value.

[0065] Although the illustrative specific embodiments of the present invention have been described above to enable those skilled in the art to understand the invention, it should be understood that the invention is not limited to the scope of the specific embodiments. For those skilled in the art, various changes are obvious as long as they are within the spirit and scope of the invention as defined and determined by the appended claims, and all inventions utilizing the concept of the present invention are protected.

Claims

1. A reliable control method for airborne data bus optical links based on multimode PON, characterized in that, Includes the following steps: (1) Bus initialization; The airborne data bus optical link reliable control system based on multimode PON is referred to as the control system. Power on the control system, initialize the first bus controller and the second bus controller to enable the data receiving function, and start the internal bus cycle timer. (2) Redundancy control; The first bus controller listens to the bus link signal through its optical network unit (ONU) interface. If it does not listen to a valid bus cycle control command within a predetermined N consecutive bus cycles, it determines that the bus control right is idle and then periodically sends bus cycle control commands through the optical line terminal (OLT) interface to obtain bus control right; where N is an integer greater than or equal to 2. The second bus controller receives bus cycle control commands from the first bus controller through its ONU interface. When it senses that the first bus controller has gained control, it sets itself as a backup controller. Then, the second bus controller continuously monitors the bus cycle control commands sent by the first bus controller. If it does not receive the command within a predetermined M bus cycles, it determines that the first bus controller has failed and confirms it through interrupt reporting and discrete data lines. When the confirmation result is true, the second bus controller immediately sends a bus cycle control command through its OLT interface and takes over bus control. Where M is an integer greater than or equal to 2; (3) Bus terminal operation management; (3.1) The bus controller that has acquired control is used as the master bus controller. According to the bus cycle and based on the pre-configured bus terminal valid address table, the status query command is sent to each bus terminal address in sequence through the dual OLT interface. (3.2) The bus terminal receives the query command through its dual ONU interface and parses the query command; then it compares whether the command address in the query command matches its own address. If the command address matches its own address, it proceeds to step (3.3); otherwise, it proceeds to step (3.4). (3.3) The bus terminal sends online response data to the main bus controller through the ONU interface. After receiving the online response data, the main bus controller adds the address of the bus terminal to the bus online terminal control table. Subsequently, the main bus controller, according to the bus online terminal control table, organizes the bus terminal to perform bus data communication according to the bus cycle. The communication process is as follows: The main bus controller sends data query commands to the bus terminal through the OLT interface in address order. If the bus terminal has bus data to send at this time, it responds with the data query command and sends the bus data to the main bus controller. The main bus controller performs integrity verification on the received bus data. If the verification passes, it sends a data reception confirmation command to the bus terminal. If the verification fails, a receive failure command is sent to the bus terminal, and the data to be sent is marked as pending retransmission. The main bus controller dynamically monitors the communication status of online terminals. When the main bus controller queries the bus terminal again in a subsequent bus cycle, the bus terminal prioritizes sending data marked as pending retransmission. If a bus terminal fails to send data for K consecutive times, it is deleted from the online control table and re-queried and registered. Finally, the main bus controller broadcasts the confirmed bus data to the bus link through the dual OLT interface. All online bus terminals on the bus link receive bus data through their dual ONU interfaces. (3.4) The bus terminal ignores the query command, does not send online response data, and does not participate in the reliable data communication organized by the main bus controller; (3.5) During the bus operation, the backup bus controller continuously executes the redundancy control logic defined in step (2), that is: it listens for the bus cycle control command issued by the main bus controller through its ONU interface. If the command is not received within a predetermined M bus cycles, the main bus controller is determined to be faulty and is jointly confirmed by interrupt reporting and discrete data lines. When the confirmation result is true, the backup bus controller is immediately upgraded to a new main bus controller, takes over the bus control, and starts to execute the bus terminal operation management process from step (3.1).

2. The airborne data bus optical link reliability control method based on multimode PON according to claim 1, characterized in that, The control system includes a bus controller 1, a bus controller 2, multiple bus terminals, a multimode optical cable, and a multimode optical splitter; Among them, bus controller 1 and bus controller 2 have two mutually redundant OLT bus interfaces and two mutually redundant ONU bus interfaces; the bus terminal has two mutually redundant ONU bus interfaces; the multimode optical cable and the multimode optical splitter constitute two mutually redundant optical signal transmission medium channels.

Images