Optical fiber communication system for in-vehicle network and redundancy protection method thereof

Abstract

This invention discloses an optical fiber communication system for vehicular networks and its redundancy protection method, belonging to the field of vehicular network technology. The method includes deploying an uplink laser and a downlink laser on the central controller side, respectively providing light sources for the uplink and downlink. When a failure of either laser is detected, the other normally functioning laser is switched to become the shared light source. A variable optical splitter dynamically adjusts the splitting ratio, allocating optical power to the uplink and downlink as needed, thus simultaneously providing light to high-priority terminal devices. This invention uses mutual backup between the uplink and downlink lasers, eliminating the need for additional backup lasers and reducing costs. Simultaneously, the variable optical splitter enables topology reconstruction and on-demand optical power allocation, improving the reliability of the vehicular optical fiber communication system in wide temperature ranges and strong vibration environments. It is particularly suitable for redundancy protection of critical services such as forward-looking cameras and instrument panels in autonomous vehicles.

Description

Technical Field

[0001] This invention relates to an optical fiber communication system for vehicle-mounted networks and a redundancy protection method thereof, belonging to the field of vehicle-mounted network technology. Background Technology

[0002] As the intelligent connected vehicle industry enters the application phase, the large-scale deployment of advanced autonomous driving technology is accelerating the performance upgrade of in-vehicle perception and interaction devices, thereby placing unprecedentedly stringent demands on the communication capabilities of in-vehicle networks. For autonomous driving systems to achieve accurate perception and real-time decision-making of the surrounding environment, the core reliance is on the collaborative work of various sensors. Among them, high-definition cameras, as the core of visual perception, are rapidly iterating towards higher resolution, higher frame rates, and higher color bit depth. Simultaneously, the development of large-screen, multi-screen, and high-definition displays in smart cockpits will lead to a significant increase in the required signal communication bandwidth due to the improved performance of in-vehicle cameras / displays.

[0003] In the evolution of in-vehicle network technology, traditional solutions mainly rely on cable connections, with interconnection speeds generally below 20Mb / s. Even the latest high-speed serial electrical interface technology for vehicles only supports communication bandwidths of around 10Gb / s, a significant gap compared to the massive data transmission demands of current in-vehicle devices. This has become a core bottleneck restricting the upgrade of intelligent connected vehicles to advanced autonomous driving and high-end intelligent cockpits. Future fully autonomous vehicles will employ more sensors to improve their ability to detect surrounding targets, and the accuracy of these sensors will be further improved, resulting in bandwidth requirements increasing to 50Gbps and above.

[0004] Fiber optic communication, with its inherent advantages of high bandwidth, light weight, and good electromagnetic compatibility, has become a core development direction for automotive networks. However, compared to data center optical interconnect systems, automotive optical networks face more stringent application environments. Typical operating conditions during vehicle operation, such as wide temperature range and strong vibration, prevent the direct transfer of data center optical communication technology. Therefore, it is necessary to develop optical network technologies specifically adapted to the automotive environment. Furthermore, automakers have made clear demands for cost control in automotive optical networks, requiring that their cost not exceed that of cable technology with equivalent speeds. Cost control has become a core prerequisite for the commercialization of automotive optical networks. With the advancement of L4 and higher-level autonomous driving technologies, it is explicitly required that L4 autonomous vehicles can automatically pull over when a fault recorded in their safety profile occurs. This necessitates that automotive optical networks possess extremely high transmission stability and fault redundancy capabilities to ensure real-time, lossless transmission of perception data and control commands.

[0005] Against this backdrop, various technical solutions have emerged in the industry, among which the most representative include the automotive optical Ethernet architecture and automotive passive optical network (PON) solutions proposed by the IEEE 802.3cz standard.

[0006] The IEEE 802.3cz standard, released in 2023, explicitly proposes the use of multimode vertical-cavity surface-emitting lasers (VCSELs) and multimode fiber (MMF) to construct an in-vehicle optical Ethernet architecture. This architecture can effectively improve the communication bandwidth of the in-vehicle network and adapt to the massive data transmission demands generated by terminal devices such as in-vehicle cameras and displays. All terminal devices that need to communicate with the vehicle's central controller contain lasers.

[0007] In a vehicle-mounted PON, an Optical Line Terminal (OLT) and an optical burst transceiver module are located at the central controller. Multiple Optical Network Units (ONUs) and the optical burst transceiver module throughout the vehicle are connected via optical splitters in the Optical Distribution Network (ODN). Terminal devices that need to communicate with the central controller, such as cameras and displays, connect to the OLT of the vehicle-mounted PON through the ONUs. Both the OLT and the ONUs contain lasers.

[0008] In both of the aforementioned architectures, the uplink channel for sending data from the terminal device to the central controller typically requires placing the laser near the terminal device. These terminal devices are widely distributed, some operating in high-temperature environments. Furthermore, their limited size makes it difficult to equip them with thermoelectric coolers (TEC) and liquid / air cooling systems. Their built-in optical emission modules must meet the automotive-grade standard of −40°C to 105°C specified in AEC-Q100 Grade 2. The accumulation of laser cavity surface defects and the combined effects of thermal stress and bias current electrical stress at high temperatures pose a significant challenge to the reliability of lasers and optical transmitters across a wide temperature range.

[0009] To address this issue, the industry has proposed an in-vehicle optical network employing a remote light source. Taking an in-vehicle PON architecture as an example, its network architecture diagram is shown below. Figure 1As shown, the system consists of a central controller and multiple terminal devices. The central controller, as the core computing unit of the intelligent connected vehicle, performs calculations such as sensor fusion, environmental recognition, and decision control, while also generating control data for the display screen. The terminal devices are distributed in different parts of the vehicle, covering all onboard sensing and interaction devices requiring high-speed data transmission. Core components include: onboard cameras with built-in light modulators and onboard displays with built-in light receiving modules. For clarity, only four cameras and four displays are shown in the diagram, and only one camera and one display show the built-in modulator and light receiver internally. The overall system communication follows a point-to-multipoint network topology. The channel through which signals are sent from the terminal devices to the central controller is called the uplink (UL), and the terminal devices that need to send data to the central controller are called uplink terminal devices (using the onboard camera as an example). The link through which signals are sent from the central controller to the terminal devices is called the downlink (DL), and the terminal devices that need to receive data from the central controller are called downlink terminal devices (using the onboard display screen as an example). Note that a terminal device can be both an uplink and a downlink terminal device.

[0010] The central controller is deployed in a relatively small temperature range (e.g., -20°C to +85°C) within the car cabin, or in a location where thermoelectric coolers (TEC) or liquid / air cooling can be used to control the temperature of the optical modules. Therefore, a high-power continuous-wave laser is used for the uplink channel transmitting high-speed data from the cameras. This laser is remotely placed at the central controller, which has temperature control capabilities, and supplied to multiple cameras via passive splitters and optical fibers. Each camera has a built-in optical modulator with high reliability over a wide temperature range. After loading high-speed uplink data, it combines the optical signals from other cameras with a single optical signal via a passive combiner before being sent to the optical receiver at the central controller. For the downlink channel, which broadcasts data from the central controller to the display screen, a high-power directly modulated laser (DML) can be used since the transmitter is located at the central controller.

[0011] Taking uplink data communication as an example, the uplink signal flow processing under normal conditions is as follows: Figure 2As shown, the vehicle-mounted camera collects ambient perception data. A modulator near the camera loads the perceived data electrical signal onto a continuous-wave optical signal emitted by a remotely placed laser. Within its assigned time slot, the optical signal is transmitted to an optical combiner. The optical combiner merges the uplink optical signals (from different time slots) from all cameras into a single optical signal, which is then transmitted to a single uplink optical receiver within the OLT at the central controller. This optical receiver does not need to distinguish between signals from different cameras; it only needs to receive the optical signals from all time slots in chronological order. The OLT's signal processing unit then demultiplexes the signals to separate and process the signals from each camera. Compared to the traditional approach of one optical receiver per camera, this solution requires only one uplink optical receiver to receive uplink data from all cameras, significantly reducing the number of uplink optical receivers required.

[0012] The remote light source solution can also be used for automotive optical Ethernet, and its architecture is shown in the figure. Figure 3 This architecture also places the laser remotely at a central controller with temperature control. However, the communication method differs from the vehicle-mounted PON architecture. The overall communication of this system is a point-to-point network topology. Therefore, the uplink no longer requires an optical combiner; multiple cameras communicate with multiple optical receivers in the central controller via point-to-point connections. For the downlink, the central controller can use multiple optical transmitters, such as DMLs, to communicate with multiple displays via point-to-point connections.

[0013] Of course, the uplink and downlink of the vehicle network can also choose their architecture independently. For example, the uplink can adopt a point-to-point vehicle optical Ethernet architecture, and the downlink can adopt a point-to-multipoint vehicle passive optical network architecture; or the uplink can adopt a multipoint-to-point vehicle passive optical network architecture, and the downlink can adopt a point-to-point vehicle optical Ethernet architecture.

[0014] However, in both of these architectures, all cameras use the same continuous-wave laser, and when the downlink adopts a point-to-multipoint vehicular passive optical network architecture, all displays also use the same DML. As the device with the highest failure rate in optical communication systems, the failure of the laser (continuous-wave laser or DML) will cause all cameras or displays to fail simultaneously, directly endangering driving safety and reducing the reliability of the vehicular optical network. Summary of the Invention

[0015] The purpose of this invention is to overcome the shortcomings of the prior art and provide an optical fiber communication system for vehicle networks and its redundancy protection method. By using uplink and downlink lasers to back each other up, no additional backup lasers are needed, which reduces costs. At the same time, by using a variable optical splitter to achieve topology reconstruction and on-demand allocation of optical power, the reliability of the vehicle optical fiber communication system in a wide temperature range and strong vibration environment is improved. It is especially suitable for redundancy protection of critical services such as forward-looking cameras and instrument panels in autonomous vehicles.

[0016] To achieve the above objectives, the present invention is implemented using the following technical solution:

[0017] In a first aspect, the present invention provides a redundancy protection method for an optical fiber communication system for a vehicle network. The vehicle network includes a central controller and multiple terminal devices. Among the multiple terminal devices, a terminal device that needs to send data to the central controller is defined as an uplink terminal device, and a terminal device that needs to receive data from the central controller is defined as a downlink terminal device. The optical signal transmission channel between the uplink terminal device and the central controller is defined as an uplink, and the optical signal transmission channel between the downlink terminal device and the central controller is defined as a downlink.

[0018] The central controller is equipped with an uplink laser and a downlink laser. The uplink laser is used to provide a light source for the uplink, and the downlink laser no longer uses DML to load data, but is only used to provide a light source for the downlink.

[0019] The redundancy protection method includes:

[0020] Detect the operating status of the uplink laser and the downlink laser;

[0021] When a fault is detected in the uplink laser or the downlink laser, the other normally functioning laser will be switched to the shared light source.

[0022] By dynamically adjusting the splitting ratio of the shared light source using a variable optical splitter, the optical power output by the shared light source is allocated to the uplink and the downlink as needed, so as to simultaneously provide light source for high-priority terminal devices in the uplink and downlink.

[0023] Furthermore, the step of switching the other normally functioning laser to a shared light source when a fault is detected in either the uplink laser or the downlink laser includes:

[0024] When the uplink laser fails, the downlink laser is used as the common light source. Its output continuous wave optical signal is split into two parts by the first variable optical splitter. One part is used for the downlink and the other part is redirected to the uplink.

[0025] When the downlink laser fails, the uplink laser is used as the common light source. Its output continuous wave optical signal is split into two parts by the second variable optical splitter. One part is used for the uplink, and the other part is redirected to the downlink.

[0026] Furthermore, the step of dynamically adjusting the splitting ratio of the common light source via a variable optical splitter includes:

[0027] Under normal conditions, the first variable optical splitter connected to the uplink laser is controlled to use a first splitting ratio to supply light separately to the uplink; the second variable optical splitter connected to the downlink laser is controlled to use a second splitting ratio to supply light separately to the downlink.

[0028] In an emergency, the actual splitting ratio of the variable optical splitter connected to the shared light source is calculated and adjusted in real time based on the total uplink and downlink optical power required by the high-priority terminal equipment.

[0029] Furthermore, the first splitting ratio is 100:0, so that all the optical power of the uplink laser is used for the uplink; the second splitting ratio is 100:0, so that all the optical power of the downlink laser is used for the downlink.

[0030] Furthermore, in the emergency situation, the method further includes:

[0031] The variable optical splitter connected to the shared light source is controlled to select only the output port corresponding to the high-priority terminal device and to close the output port corresponding to the low-priority terminal device.

[0032] Furthermore, the method also includes:

[0033] In the emergency state, control commands are sent to the high-priority terminal devices to reduce the resolution or data transmission bandwidth of non-critical terminal devices in the high-priority terminal devices, so as to reduce the power budget requirements of the link they are on.

[0034] Furthermore, the variable optical splitter includes a 1:2 variable optical splitter and a 2:N variable optical splitter;

[0035] The 1:2 variable optical splitter is used to split one optical signal into two, with one input port used to connect to a single laser and to dynamically distribute optical power between the two output ports.

[0036] The 2:N variable optical splitter is used to select one optical signal input between two input ports, and then divide this input optical signal into N paths and dynamically distribute the optical power among N output ports. The N output ports are respectively connected to N terminal devices.

[0037] Furthermore, the method is applied to an in-vehicle passive optical network architecture, wherein the uplink terminal device includes an in-vehicle camera with a built-in modulator, and the downlink terminal device includes an in-vehicle display screen with a built-in optical receiving module; the central controller side includes an uplink optical receiver for simultaneously receiving time-division multiplexed burst data signals from multiple cameras and a downlink optical modulator loaded with broadcast data signals for simultaneously transmitting to multiple displays.

[0038] In the emergency state, a portion of the continuous wave light signal output by the shared light source is distributed as needed to one or more high-priority vehicle-mounted cameras via some or all of the output ports of the first 2:N variable optical splitter, serving as their remote light source; another portion is modulated into downlink broadcast data by the modulator and then distributed as needed to one or more high-priority vehicle-mounted displays via some or all of the output ports of the second 2:N variable optical splitter.

[0039] Furthermore, the method is applied to an in-vehicle optical Ethernet architecture. In this architecture, the central controller includes multiple uplink optical receivers that receive ordinary continuous data signals and multiple downlink optical modulators loaded with independent data signals. Each uplink optical receiver communicates point-to-point with an in-vehicle camera serving as an uplink terminal device, and the output port of the variable optical splitter is connected to each in-vehicle camera to provide a remote light source. In the downlink, a laser located at the central controller is split by the optical splitter and connected to multiple optical modulators. Each optical modulator communicates point-to-point with an in-vehicle display screen serving as a downlink terminal device via optical fiber.

[0040] In the emergency state, a portion of the continuous wave optical signal output by the shared light source is distributed as needed to one or more high-priority vehicle-mounted cameras via some or all of the output ports of the first 2:N variable optical splitter, serving as their remote light source; another portion is distributed as needed to one or more downlink optical modulators via some or all of the output ports of the second 2:N variable optical splitter, and after each path of downlink data is independently modulated, it is connected to one or more high-priority vehicle-mounted displays via optical fiber.

[0041] Secondly, the present invention provides an optical fiber communication system for vehicle-mounted networks, comprising:

[0042] Multiple terminal devices, including uplink terminal devices and downlink terminal devices; the uplink terminal devices are used to send data to the central controller, and the downlink terminal devices are used to receive data from the central controller;

[0043] Uplink lasers and downlink lasers are deployed on the central controller side. The uplink lasers are used to provide a light source for the uplink, and the downlink lasers are used to provide a light source for the downlink. The uplink is an optical signal transmission channel between the uplink terminal device and the central controller, and the downlink is an optical signal transmission channel between the downlink terminal device and the central controller.

[0044] A variable optical splitter is connected between the uplink laser, the downlink laser, and the multiple terminal devices;

[0045] The control unit is connected to the uplink laser and the downlink laser, and enables the variable optical splitter to perform beam splitting through the control link. The control unit is used to implement the redundancy protection method described in any of the preceding claims.

[0046] Furthermore, the downlink of the system is independently selected from any of the following architectures:

[0047] The vehicle-mounted passive optical network architecture communicates with the vehicle-mounted display screen, which serves as the downlink terminal device, via a point-to-multipoint broadcast method.

[0048] Alternatively, in a vehicle-mounted optical Ethernet architecture, a laser is set at the central controller, and after being split by an optical splitter, it is connected to multiple optical modulators. Each optical modulator communicates with a vehicle-mounted display screen, which serves as a downlink terminal device, via optical fiber in a point-to-point manner.

[0049] The uplink of the system is independently selected from any of the following architectures:

[0050] In the vehicle-mounted passive optical network architecture, multiple vehicle-mounted cameras, which act as uplink terminal devices, communicate with a single optical receiver on the central controller side in a multi-point-to-point manner through an optical combiner.

[0051] Alternatively, in a vehicle-mounted optical Ethernet architecture, the central controller side includes multiple optical receivers, each optical receiver communicating with a vehicle-mounted camera as an uplink terminal device in a point-to-point manner, and the output port of the variable optical splitter is connected to each vehicle-mounted camera to provide them with a remote light source.

[0052] The architectures of the downlink and the uplink are selected independently.

[0053] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0054] This invention provides an optical fiber communication system for vehicular networks and its redundancy protection method. By centrally deploying uplink and downlink lasers on the central controller side and using them respectively for the uplink and downlink light source supply, when a failure of any laser is detected, the other normally functioning laser is switched to the shared light source. The splitting ratio is dynamically adjusted by a variable optical splitter, and the optical power is distributed to the uplink and downlink as needed to ensure the service continuity of high-priority terminal equipment. This achieves mutual backup of uplink and downlink lasers without the need for additional backup lasers, thereby significantly reducing hardware deployment and power consumption costs. At the same time, by centrally placing temperature-sensitive lasers in the central controller area with temperature control conditions and replacing the dispersed lasers with a shared remote light source, the reliability of devices in a wide temperature range and strong vibration environment is effectively guaranteed. In addition, for the lasers with the highest failure rate in optical communication systems, this solution can support critical uplink and downlink services simultaneously with a single shared light source in the event of a failure, ensuring the effectiveness of system operation and greatly improving the ability of the vehicular optical fiber communication system to cope with optical device failures. Attached Figure Description

[0055] Figure 1 This is a schematic diagram of a remote light source vehicle-mounted passive optical network architecture provided by the background technology of this invention;

[0056] Figure 2 This is a schematic diagram of normal uplink signal processing provided by the background technology of this invention;

[0057] Figure 3 This is a schematic diagram of the remote light source vehicle-mounted optical Ethernet architecture provided in the background technology of this invention;

[0058] Figure 4 This is a schematic diagram of the vehicle-mounted passive optical network architecture provided in an embodiment of the present invention;

[0059] Figure 5 This is a schematic diagram of the vehicle-mounted optical Ethernet architecture provided in an embodiment of the present invention;

[0060] Figure 6 This is a schematic diagram of emergency signal processing in a point-to-multipoint architecture provided in an embodiment of the present invention;

[0061] Figure 7 This is a schematic diagram of emergency status signal processing using a point-to-point architecture provided in an embodiment of the present invention. Detailed Implementation

[0062] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0063] Example 1: This example introduces a redundancy protection method for an optical fiber communication system used in a vehicle network. The vehicle network includes a central controller and multiple terminal devices. Among the multiple terminal devices, the terminal device that needs to send data to the central controller is defined as an uplink terminal device, and the terminal device that needs to receive data from the central controller is defined as a downlink terminal device. The optical signal transmission channel between the uplink terminal device and the central controller is defined as the uplink link, and the optical signal transmission channel between the downlink terminal device and the central controller is defined as the downlink link.

[0064] The central controller is equipped with an uplink laser and a downlink laser. The uplink laser is used to provide a light source for the uplink, and the downlink laser is used to provide a light source for the downlink.

[0065] The redundancy protection method includes:

[0066] Detect the operating status of the uplink laser and the downlink laser;

[0067] When a fault is detected in the uplink laser or the downlink laser, the other normally functioning laser will be switched to the shared light source.

[0068] By dynamically adjusting the splitting ratio of the shared light source using a variable optical splitter, the optical power output by the shared light source is allocated to the uplink and the downlink as needed, so as to simultaneously provide light source for high-priority terminal devices in the uplink and downlink.

[0069] This embodiment employs a redundancy protection method for a fiber optic communication system used in a vehicle-mounted network. The vehicle-mounted network includes a central controller and multiple terminal devices. Among the terminal devices, those that need to send data to the central controller are defined as uplink terminal devices, and those that need to receive data from the central controller are defined as downlink terminal devices. The optical signal transmission channel between the uplink terminal device and the central controller is defined as the uplink, and the optical signal transmission channel between the downlink terminal device and the central controller is defined as the downlink. The central controller is deployed inside the vehicle cabin or in a location where temperature control measures such as thermoelectric cooling, liquid cooling, or air cooling are permissible. Uplink and downlink lasers are deployed on the central controller side; the uplink laser provides light for the uplink, and the downlink laser provides light for the downlink.

[0070] In this embodiment, as Figure 4 and Figure 5As shown, both the uplink and downlink lasers are high-power continuous-wave lasers. An external modulator is connected to the downlink laser to modulate the downlink data onto the optical carrier. A variable optical splitter connects the uplink and downlink lasers to multiple terminal devices. Variable optical splitters include 1:2 and 2:N types. The 1:2 splitter splits one optical signal into two, with one input port connected to a single laser, and dynamically distributes optical power between the two output ports. The 2:N splitter selects one optical signal input from the two input ports, then splits this input signal into N paths, dynamically distributing optical power among the N output ports, which are connected to N terminal devices.

[0071] The redundancy protection method in this embodiment first detects the operating status of the uplink and downlink lasers. When a fault is detected in either the uplink or downlink laser, the other normally operating laser is switched to become the shared light source. If the uplink laser fails, the downlink laser is used as the shared light source, and the continuous wave optical signal output by the downlink laser is split into two parts by a first 1:2 variable optical splitter; one part is used for the downlink, and the other part is redirected to the uplink. If the downlink laser fails, the uplink laser is used as the shared light source, and the continuous wave optical signal output by the uplink laser is split into two parts by a second 1:2 variable optical splitter; one part is used for the uplink, and the other part is redirected to the downlink.

[0072] By dynamically adjusting the splitting ratio of a shared light source using variable optical splitters, the optical power output from the shared light source is allocated to the uplink and downlink as needed, simultaneously providing light to high-priority terminal devices in both the uplink and downlink to ensure service continuity. Under normal conditions, the first 1:2 variable optical splitter connected to the uplink laser operates at a 100:0 splitting ratio, supplying light solely to the uplink; the second 1:2 variable optical splitter connected to the downlink laser operates at a 100:0 splitting ratio, supplying light solely to the downlink. In emergency situations, the actual splitting ratio of the 1:2 variable optical splitters connected to the shared light source is calculated and adjusted in real time based on the total uplink and downlink optical power required by the high-priority terminal devices.

[0073] High-priority terminal devices are prioritized based on service priority. Among uplink terminal devices, the forward-view camera has the highest service priority, followed by the side-view and surround-view cameras. Among downlink terminal devices, the instrument panel and the driver's side center console screen have the highest service priority. In emergency situations, the 2:N variable optical splitter connected to the control and shared light source routes optical signals only to the output ports corresponding to high-priority terminal devices and stops allocating optical power to the output ports corresponding to low-priority terminal devices. Simultaneously, in emergency situations, control commands are sent to high-priority terminal devices to reduce the resolution or data transmission bandwidth of non-critical terminal devices within the high-priority terminal devices, thereby reducing the power budget requirements of their respective links.

[0074] The method in this embodiment is applied to in-vehicle passive optical network architectures or in-vehicle optical Ethernet architectures. When applied to in-vehicle passive optical network architectures, such as... Figure 4 As shown, the uplink terminal equipment includes a vehicle-mounted camera with a built-in modulator, and the downlink terminal equipment includes a vehicle-mounted display screen with a built-in optical receiving module. In an emergency, a portion of the continuous wave optical signal output from the shared light source is distributed as needed to one or more high-priority vehicle-mounted cameras via some or all of the output ports of the first 2:N variable optical splitter, serving as their remote light source; the other portion is modulated into downlink broadcast data by the modulator and then distributed as needed to one or more high-priority vehicle-mounted displays via some or all of the output ports of the second 2:N variable optical splitter.

[0075] When applied to automotive optical Ethernet architecture, such as Figure 5 As shown, the central controller includes multiple optical receivers, each communicating point-to-point with an onboard camera serving as an uplink terminal. The output ports of a variable optical splitter are connected to each onboard camera, providing them with a remote light source. In this architecture, multiple cameras communicate point-to-point with multiple optical receivers in the central controller, but the laser still provides continuous wave light signals to all cameras by sharing a remote light source. The variable optical splitter allocates optical power as needed.

[0076] The key technical point of this embodiment lies in overcoming the high cost bottleneck of traditional automotive optical Ethernet. It adopts an architecture combining a shared remote light source and a passive optical distribution network. High-power lasers are deployed in temperature-controlled areas such as the vehicle cabin. Multiple automotive cameras and displays are provided with a shared light source via fiber optics and variable optical splitters. The cameras have built-in, reliable optical modulators with a wide temperature range, eliminating the need for independent light sources for each terminal and significantly reducing the number of optical modules required. Furthermore, addressing the issue of laser failure, this embodiment quantifies business requirements and develops a reasonable remote light source backup strategy based on the characteristics of automotive architecture, balancing low cost, high reliability, and adaptability to wide temperature range and strong vibration environments.

[0077] The core protection concept of this embodiment is reflected in the following aspects: First, in a vehicle-mounted fiber optic communication system with a central controller and multiple terminal devices, lasers are deployed in the temperature-controlled area around the central controller as a shared remote light source, providing light for terminal devices located throughout the vehicle. Cameras and displays are deployed throughout the vehicle body without the need for temperature control devices. The cameras have built-in optical modulators, and the displays have built-in optical receiver modules. The light sources required by the slave nodes are all provided remotely by the master node via fiber optics without the need for separate independent light sources. Second, the uplink signal transmission adopts a burst-mode time-division multiplexing method. The modulator allocates dedicated time slots to transmit the optical signal carrying the sensing data to a passive optical combiner. The optical combiner combines multiple time-slot signals into one and transmits it to a single optical receiver inside the central controller. After demultiplexing, the data from each camera is separated, reducing the number of optical receivers used. Third, the downlink signal uses a broadcast transmission method. The laser of the central controller, in conjunction with an external modulator, loads display control data. The signal is split into multiple paths via a variable optical splitter and broadcast to all display screen slave nodes through single-mode fiber. Each display screen's optical receiving module extracts the data it needs based on the destination address information in the data frame, eliminating the need for a separate downlink optical transmitter for each display screen. Fourth, the uplink and downlink laser redundancy protection is implemented by using a laser as the uplink light source for the central controller and a laser with an external modulator as the downlink optical transmitter. When either laser fails, the other laser adjusts the splitting ratio via the variable optical splitter to provide light for both the uplink and downlink, eliminating the need for an additional backup laser. Fifth, the optical power topology reconfiguration and on-demand optical power allocation are implemented as follows: under normal operating conditions, a 1:2 splitter uses a 100:0 splitting ratio to supply light separately for either the uplink or downlink. Under fault conditions, the splitting ratio is adjusted to meet the power requirements of critical uplink and downlink services. A 2:N splitter can switch inputs between two lasers, and the splitting ratio of each output port can be flexibly adjusted according to the slave node's power budget.

[0078] This embodiment has the following advantages compared to the prior art:

[0079] In terms of high-temperature reliability, this network only centrally places temperature-sensitive lasers in the car cabin or near the central controller with temperature control conditions, replacing the dispersed lasers with a shared, remotely centralized high-power continuous wave laser. This not only ensures the reliability of the lasers over a wide temperature range, but also facilitates the protection of critical services for these lasers through redundant configuration. Even if the temperature in the car cabin exceeds the acceptable temperature range of the temperature-sensitive uplink lasers and downlink optical transmitters, thermoelectric coolers can be placed in the central controller area to ensure that the lasers operate within an acceptable temperature range.

[0080] This embodiment has significant low-cost advantages. By providing redundancy protection through mutual backup of uplink and downlink lasers, the number of lasers that need to be pre-deployed is reduced, simplifying the architecture and reducing hardware, deployment and power consumption costs.

[0081] This embodiment can better address the problem of optical device failure. For lasers, which have the highest failure rate in optical communication systems, this system adopts a strategy of uplink and downlink laser redundancy protection. In the emergency state of a laser failure, another laser can be used as the uplink and downlink light source at the same time without the need to add an extra backup light source. This not only ensures the effectiveness of system operation, but also greatly controls costs.

[0082] Example 2, as Figure 6 and Figure 7 As shown, this embodiment provides an optical fiber communication system for vehicle-mounted networks, including:

[0083] Multiple terminal devices, including uplink terminal devices and downlink terminal devices; the uplink terminal devices are used to send data to the central controller, and the downlink terminal devices are used to receive data from the central controller;

[0084] Uplink lasers and downlink lasers are deployed on the central controller side. The uplink lasers are used to provide a light source for the uplink, and the downlink lasers are used to provide a light source for the downlink. The uplink is an optical signal transmission channel between the uplink terminal device and the central controller, and the downlink is an optical signal transmission channel between the downlink terminal device and the central controller.

[0085] A variable optical splitter is connected between the uplink laser, the downlink laser, and the multiple terminal devices;

[0086] The control unit is connected to the uplink laser and the downlink laser, and enables the variable optical splitter to perform beam splitting through the control link. The control unit is used to implement the redundancy protection method described in any one of Embodiment 1.

[0087] like Figure 6 and Figure 7 As shown, the downlink of the system is independently selected from any of the following architectures:

[0088] The vehicle-mounted passive optical network architecture communicates with the vehicle-mounted display screen, which serves as the downlink terminal device, via a point-to-multipoint broadcast method.

[0089] Alternatively, in a vehicle-mounted optical Ethernet architecture, a downlink laser is set at the central controller, which is split by an optical splitter and connected to multiple optical modulators. Each optical modulator communicates with a vehicle-mounted display screen, which serves as a downlink terminal device, via optical fiber in a point-to-point manner.

[0090] The uplink of the system is independently selected from any of the following architectures:

[0091] In the vehicle-mounted passive optical network architecture, multiple vehicle-mounted cameras, which act as uplink terminal devices, communicate with a single optical receiver on the central controller side in a multi-point-to-point manner through an optical combiner.

[0092] Alternatively, in a vehicle-mounted optical Ethernet architecture, the central controller side includes multiple optical receivers, each optical receiver communicating with a vehicle-mounted camera as an uplink terminal device in a point-to-point manner, and the output port of the variable optical splitter is connected to each vehicle-mounted camera to provide them with a remote light source.

[0093] The architectures of the downlink and the uplink are selected independently.

[0094] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principle of the present invention. For example, one uplink laser and one downlink laser can be expanded into multiple uplink lasers and multiple downlink lasers. These improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A redundancy protection method for an optical fiber communication system used in a vehicle-mounted network, characterized in that, The vehicle network includes a central controller and multiple terminal devices. Among the multiple terminal devices, the terminal device that needs to send data to the central controller is defined as an uplink terminal device, and the terminal device that needs to receive data from the central controller is defined as a downlink terminal device. The optical signal transmission channel between the uplink terminal device and the central controller is defined as an uplink, and the optical signal transmission channel between the downlink terminal device and the central controller is defined as a downlink. The central controller is equipped with an uplink laser and a downlink laser. The uplink laser is used to provide a light source for the uplink, and the downlink laser is used to provide a light source for the downlink. The redundancy protection method includes: Detect the operating status of the uplink laser and the downlink laser; When a fault is detected in the uplink laser or the downlink laser, the other normally functioning laser will be switched to the shared light source. By dynamically adjusting the splitting ratio of the shared light source using a variable optical splitter, the optical power output by the shared light source is allocated to the uplink and the downlink as needed, so as to simultaneously provide light source for high-priority terminal devices in the uplink and downlink.

2. The redundancy protection method for an optical fiber communication system for a vehicle-mounted network according to claim 1, characterized in that, When a malfunction is detected in either the uplink laser or the downlink laser, switching the other normally functioning laser to the shared light source includes: When the uplink laser fails, the downlink laser is used as the common light source. Its output continuous wave optical signal is split into two parts by the first variable optical splitter. One part is used for the downlink and the other part is redirected to the uplink. When the downlink laser fails, the uplink laser is used as the common light source. Its output continuous wave optical signal is split into two parts by the second variable optical splitter. One part is used for the uplink, and the other part is redirected to the downlink.

3. The redundancy protection method for an optical fiber communication system for a vehicle-mounted network according to claim 1, characterized in that, The method of dynamically adjusting the splitting ratio of the shared light source via a variable optical splitter includes: Under normal conditions, the first variable optical splitter connected to the uplink laser is controlled to use a first splitting ratio to supply light separately to the uplink; the second variable optical splitter connected to the downlink laser is controlled to use a second splitting ratio to supply light separately to the downlink. In an emergency, the actual splitting ratio of the variable optical splitter connected to the shared light source is calculated and adjusted in real time based on the total uplink and downlink optical power required by the high-priority terminal equipment. And / or, the first splitting ratio is 100:0, so that all the optical power of the uplink laser is used for the uplink and not split for the downlink; the second splitting ratio is 100:0, so that all the optical power of the downlink laser is used for the downlink and not split for the uplink.

4. The redundancy protection method for an optical fiber communication system for a vehicle-mounted network according to claim 3, characterized in that, In the aforementioned emergency situation, the method further includes: The variable optical splitter connected to the shared light source is controlled to select only the output port corresponding to the high-priority terminal device and to close the output port corresponding to the low-priority terminal device.

5. The redundancy protection method for an optical fiber communication system for a vehicle-mounted network according to claim 3, characterized in that, The method further includes: In the emergency state, control commands are sent to the high-priority terminal devices to reduce the resolution or data transmission bandwidth of non-critical terminal devices in the high-priority terminal devices, so as to reduce the power budget requirements of the link they are on.

6. The redundancy protection method for an optical fiber communication system for a vehicle-mounted network according to claim 1, characterized in that, The variable optical splitter includes a 1:2 variable optical splitter and a 2:N variable optical splitter; The 1:2 variable optical splitter is used to split one optical signal into two, and dynamically distribute optical power between the two output ports. The 2:N variable optical splitter is used to select one optical signal input between two input ports, and then divide this input optical signal into N paths and dynamically distribute the optical power among N output ports. The N output ports are respectively connected to N terminal devices.

7. The redundancy protection method for an optical fiber communication system for a vehicle-mounted network according to claim 3, characterized in that, The method is applied to an in-vehicle passive optical network architecture. The uplink terminal device includes an in-vehicle camera with a built-in modulator, and the downlink terminal device includes an in-vehicle display screen with a built-in optical receiving module. The central controller includes an uplink optical receiver for simultaneously receiving time-division multiplexed burst data signals from multiple cameras and a downlink optical modulator loaded with broadcast data signals for simultaneously transmitting to multiple displays. In the emergency state, a portion of the continuous wave light signal output by the shared light source is distributed as needed to one or more high-priority vehicle-mounted cameras via some or all of the output ports of the first 2:N variable optical splitter, serving as their remote light source; another portion is modulated into downlink broadcast data by the modulator and then distributed as needed to one or more high-priority vehicle-mounted displays via some or all of the output ports of the second 2:N variable optical splitter.

8. The redundancy protection method for an optical fiber communication system for a vehicle-mounted network according to claim 3, characterized in that, The method is applied to an in-vehicle optical Ethernet architecture. The uplink terminal device includes an in-vehicle camera with a built-in modulator, and the downlink terminal device includes an in-vehicle display screen with a built-in optical receiving module. The central controller includes multiple uplink optical receivers that receive ordinary continuous data signals and multiple downlink optical modulators loaded with independent data signals. In the emergency state, a portion of the continuous wave light signal output by the shared light source is distributed as needed to one or more high-priority vehicle cameras via some or all of the output ports of the first 2:N variable optical splitter, serving as their remote light source. Another portion is distributed as needed to one or more downlink optical modulators via some or all of the output ports of the second 2:N variable optical splitter. After each downlink data is independently modulated, it is connected to one or more high-priority vehicle displays via optical fiber.

9. A fiber optic communication system for vehicle-mounted networks, characterized in that, include: Multiple terminal devices, including uplink terminal devices and downlink terminal devices; the uplink terminal devices are used to send data to the central controller, and the downlink terminal devices are used to receive data from the central controller; Uplink lasers and downlink lasers are deployed on the central controller side. The uplink lasers are used to provide a light source for the uplink, and the downlink lasers are used to provide a light source for the downlink. The uplink is an optical signal transmission channel between the uplink terminal device and the central controller, and the downlink is an optical signal transmission channel between the downlink terminal device and the central controller. A variable optical splitter is connected between the uplink laser, the downlink laser, and the multiple terminal devices; The control unit is connected to the uplink laser and the downlink laser, and enables the variable optical splitter to perform beam splitting through the control link. The control unit is used to implement the redundancy protection method according to any one of claims 1-7.

10. The fiber optic communication system for vehicle-mounted networks according to claim 9, characterized in that, The downlink of the system is independently selected from any of the following architectures: The vehicle-mounted passive optical network architecture communicates with the vehicle-mounted display screen, which serves as the downlink terminal device, via a point-to-multipoint broadcast method. Alternatively, in a vehicle-mounted optical Ethernet architecture, the laser located at the central controller is split by an optical splitter and connected to multiple optical modulators. Each optical modulator communicates with a vehicle-mounted display screen, which serves as a downlink terminal device, via optical fiber in a point-to-point manner. The uplink of the system is independently selected from any of the following architectures: In the vehicle-mounted passive optical network architecture, multiple vehicle-mounted cameras, which act as uplink terminal devices, communicate with a single optical receiver on the central controller side in a multi-point-to-point manner through an optical combiner. Alternatively, in a vehicle-mounted optical Ethernet architecture, the central controller side includes multiple optical receivers, each optical receiver communicating with a vehicle-mounted camera as an uplink terminal device in a point-to-point manner, and the output port of the variable optical splitter is connected to each vehicle-mounted camera to provide them with a remote light source. The architectures of the downlink and the uplink are selected independently.

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