Outdoor scene high-precision positioning method and system fused with Beidou signal

Abstract

The invention discloses an outdoor scene high-precision positioning method fused with Beidou signals, and the method is executed by a high-precision positioning module, and comprises the steps: obtaining vehicle positioning related information; differential correction data link quality information is obtained; acquiring scene and positioning demand information; and based on the vehicle positioning related information, the differential correction data link quality information and the scene and positioning demand information, determining that the vehicle enters one of a high-precision state, a holding state, a flow-saving state and a degradation state. Through the scheme of the invention, the positioning stability and precision can be improved in key road sections such as steering bifurcation and ramps, the flow consumption of correction data can be reduced in non-key road sections such as cruise, the positioning jump can be inhibited under the conditions of flow cutoff, delay or packet loss, and the overall navigation reliability can be improved.

Description

Technical Field

[0001] This invention relates to the field of positioning technology, and in particular to a high-precision positioning method and system for outdoor scenes that integrates BeiDou signals. Background Technology

[0002] When vehicles use satellite navigation and positioning, they typically need to receive differential correction data from ground-based augmentation systems or network differential services to achieve centimeter-level or decimeter-level high-precision positioning. Differential correction data is generally transmitted as a continuous stream, which has a certain bandwidth and data consumption, and is relatively sensitive to latency, packet loss, and data interruption.

[0003] In existing technologies, most terminals continuously receive differential correction data at a fixed frequency. In scenarios involving long-distance vehicle cruising or simple routes, continuous high-frequency reception leads to unnecessary bandwidth consumption. Furthermore, in critical road sections (such as intersections, ramps, entrances / exits, and dense road networks) and when positioning quality deteriorates, if the correction data is unavailable or insufficiently updated, phenomena such as lost fixed solutions, slowed convergence, and positioning jumps can easily occur, resulting in unstable or even misleading navigation prompts. Therefore, there is an urgent need for a technical solution that can adaptively adjust the frequency of differential correction data reception while ensuring positioning stability and recoverability in critical scenarios. Summary of the Invention

[0004] To achieve the above objectives, this invention provides a high-precision positioning method and system for outdoor scenes that integrates BeiDou signals. The high-precision positioning module acquires vehicle positioning-related information, differential correction data link quality information, and scene and positioning requirement information, and determines whether the vehicle is in a high-precision, hold, data-saving, or degradation state based on this information. Under different states, the system adaptively adjusts the reception method and frequency of differential correction data, and executes a protection strategy to output conservative positioning prompts when the link is abnormal. This solution can improve positioning stability and accuracy in critical road sections such as turning forks and ramps, reduce correction data traffic consumption in non-critical road sections such as cruising, and suppress positioning jumps in cases of data interruption, delay, or packet loss, thereby improving overall navigation reliability.

[0005] This invention provides a high-precision positioning method for outdoor scenes that integrates BeiDou signals. The method is executed by a high-precision positioning module and includes: Obtain vehicle positioning-related information, which includes at least one of the following: solution state, positioning uncertainty, and cycle slip statistics; Obtain differential correction data link quality information, which includes at least one of the following: differential correction data latency, packet loss rate, and outage events; Obtain scene and positioning requirement information, which includes at least one of the following: distance to the next turn or fork, road type, and road network complexity; and Based on vehicle positioning information, differential correction data link quality information, and scenario and positioning requirements information, the vehicle is determined to enter one of the following states: high-precision state, hold state, data-saving state, and degradation state.

[0006] In a preferred embodiment, the method further includes: If it is determined that the vehicle has entered a high-precision state, differential correction data is received in a high-frequency manner; If it is determined that the vehicle has entered hold mode, differential correction data is received in a low-to-medium frequency manner; If it is determined that the vehicle has entered the flow-saving state, differential correction data is received at low frequency or in an event-triggered manner; If the vehicle is determined to be in a degraded state, a protection strategy is implemented and a conservative positioning quality warning is output.

[0007] In a preferred embodiment, the solution states include at least: fixed solutions and floating-point solutions.

[0008] In a preferred embodiment, the vehicle is determined to have entered a high-precision state if at least one of the following conditions is met: The distance between the vehicle and the next turn or fork is less than a preset key point distance threshold; Vehicles enter ramps, entrances / exits, or interchange areas; The solution is a floating-point solution; The road network complexity exceeds the preset threshold.

[0009] In a preferred embodiment, the vehicle is determined to be in a flow-saving state if all of the following conditions are met: The solution state is a fixed solution and the time during which the solution state remains a fixed solution reaches a preset time threshold. The weekly slip count is below the preset weekly slip count threshold; The differential correction data latency is lower than the preset differential correction data latency threshold; and The packet loss rate is lower than the preset packet loss rate threshold.

[0010] In a preferred embodiment, a vehicle is determined to have entered a degradation state if at least one of the following conditions is met: The duration for which differential correction data has not been received has reached a preset duration threshold; The differential correction data delay exceeds the preset unavailable threshold; The packet loss rate exceeds the preset packet loss rate threshold within the preset time window; The positioning uncertainty exceeds the preset uncertainty threshold.

[0011] This invention provides a high-precision positioning system for outdoor scenes that integrates BeiDou signals. The system includes a high-precision positioning module, which is configured to perform the following operations: Obtain vehicle positioning-related information, which includes at least one of the following: solution state, positioning uncertainty, and cycle slip statistics; Obtain differential correction data link quality information, which includes at least one of the following: differential correction data latency, packet loss rate, and outage events; Obtain scene and positioning requirement information, which includes at least one of the following: distance to the next turn or fork, road type, and road network complexity; and Based on vehicle positioning information, differential correction data link quality information, and scenario and positioning requirements information, the vehicle is determined to enter one of the following states: high-precision state, hold state, data-saving state, and degradation state.

[0012] In a preferred embodiment, the high-precision positioning module is further configured to perform the following operations: If it is determined that the vehicle has entered a high-precision state, differential correction data is received in a high-frequency manner; If it is determined that the vehicle has entered hold mode, differential correction data is received in a low-to-medium frequency manner; If it is determined that the vehicle has entered the flow-saving state, differential correction data is received at low frequency or in an event-triggered manner; If the vehicle is determined to be in a degraded state, a protection strategy is implemented and a conservative positioning quality warning is output.

[0013] In a preferred embodiment, the solution states include at least: fixed solutions and floating-point solutions.

[0014] In a preferred embodiment, the vehicle is determined to have entered a high-precision state if at least one of the following conditions is met: The distance between the vehicle and the next turn or fork is less than a preset key point distance threshold; Vehicles enter ramps, entrances / exits, or interchange areas; The solution is a floating-point solution; The road network complexity exceeds the preset threshold.

[0015] Compared with existing technologies, this invention provides a high-precision positioning method and system for outdoor scenes that integrates BeiDou signals. The high-precision positioning module acquires vehicle positioning-related information, differential correction data link quality information, and scene and positioning requirement information, and determines whether the vehicle is in a high-precision, hold, data-saving, or degradation state based on this information. Under different states, the system adaptively adjusts the reception method and frequency of differential correction data, and executes a protection strategy to output conservative positioning prompts when the link is abnormal. This solution can improve positioning stability and accuracy in critical road sections such as turning forks and ramps, reduce correction data traffic consumption in non-critical road sections such as cruising, and suppress positioning jumps in the event of data interruption, delay, or packet loss, thereby improving overall navigation reliability. Attached Figure Description

[0016] Figure 1 This is a system logic block diagram of one embodiment of the present invention.

[0017] Figure 2 This is a schematic diagram of the internal structure of a vehicle according to an embodiment of the present invention.

[0018] Figure 3 This is a flowchart of a method according to an embodiment of the present invention.

[0019] Figure 4 This is a schematic diagram of a navigation interface according to an embodiment of the present invention.

[0020] Figure 5 This is a schematic diagram of a navigation interface according to another embodiment of the present invention.

[0021] Figure 6 This is a schematic diagram of a navigation interface according to another embodiment of the present invention.

[0022] Figure 7 This is a schematic diagram of a navigation interface according to another embodiment of the present invention. Detailed Implementation

[0023] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.

[0024] Figure 1This is a system logic block diagram of an embodiment of the present invention. As shown in the figure, the system 100 of the present invention includes a high-precision positioning module 10, which is connected to a satellite navigation receiver 20, a differential correction data receiving module 30, and a scene information acquisition module 40. The satellite navigation receiver 20 is used to receive satellite signals, including at least those from BeiDou satellites, and output vehicle positioning-related information, which includes at least one of solution status, positioning uncertainty, and cycle slip statistics. The differential correction data receiving module 30 is used to receive differential correction data through a communication link and output link quality information, which includes at least one of differential correction data delay, packet loss rate, and disconnection events. The scene information acquisition module 40 is used to acquire scene and positioning requirement information, which includes at least one of the following: distance to the next turn or fork, road type, and road network complexity. The high-precision positioning module 10 determines the state based on the above three types of information, identifying the vehicle as entering a high-precision state, a holding state, a power-saving state, or a degradation state. Based on this, it controls the receiving method and frequency of differential correction data. In the degradation state, it executes a protection strategy and outputs a conservative positioning quality prompt.

[0025] In one or more embodiments of the present invention, the high-precision positioning module 10 can be implemented in any form of structure suitable for performing the functions described herein. For example, the high-precision positioning module 10 can be implemented as hardware circuitry (including but not limited to application-specific integrated circuits, field-programmable gate arrays, digital signal processors, microprocessors, microcontrollers, system-on-a-chip, and combinations thereof), firmware (e.g., control logic, microcode, or other executable instructions stored in read-only memory or flash memory), software (e.g., program instructions executed by a processor, operating system components, drivers, or middleware), or any combination of the above hardware, firmware, and software. In some embodiments, the functions corresponding to the high-precision positioning module 10 can be implemented by instructions executed by one or more processors, which can be stored in one or more non-transitory computer-readable storage media and, when executed, cause the one or more processors to perform operations such as state determination, differential correction data reception control, and positioning quality output as described herein; in other embodiments, some or all of the functions can be implemented by hardware logic in a parallel or pipelining manner to meet real-time, power consumption, or cost constraints. It should be understood that the functional description of the high-precision positioning module 10 in this article does not limit its specific implementation form, and any implementation method that can achieve the same or equivalent functions falls within the protection scope of this invention.

[0026] Figure 2 This is a schematic diagram of the internal structure of a vehicle according to an embodiment of the present invention. Figure 2As shown, the vehicle's central control area is equipped with a vehicle infotainment system 200, which includes a display screen 205. In this embodiment, the display screen 205 is used to present a navigation interface 210, which is used to visually output navigation-related information to the user, such as current location, planned route, driving direction, and next turn prompts. The vehicle infotainment system 200 can update the current location and route guidance information in the navigation interface 210 based on the high-precision positioning results fused with BeiDou signals as described in this invention, thereby providing a display medium for subsequent route guidance and key point prompts.

[0027] Figure 3 This is a flowchart of a method according to an embodiment of the present invention. As shown in the figure, the method of the present invention includes the following steps: Step 1: Obtain vehicle location-related information, which includes at least one of the following: solution state, location uncertainty, and cycle slip statistics; In one example, the solution states of this invention include fixed solutions and floating-point solutions. Those skilled in the art should understand that in the high-precision positioning process of this invention, which integrates BeiDou signals, the receiver (or high-precision positioning module) uses carrier phase observations and differential correction data for calculation. Since the carrier phase contains "integer ambiguity" (initially unknown and usually an integer), the solution state is typically either a fixed solution or a floating-point solution. A fixed solution refers to the integer ambiguity being reliably determined as a correct integer and fixed, thereby creating a high-precision constraint on the position solution from the carrier phase. A fixed solution is generally easier to obtain under the following conditions: the differential correction data is continuously available with low delay, low packet loss, and no interruptions; the number of satellites participating in the calculation is sufficient and their geometric distribution is good; the signal quality is good, the carrier phase is continuous, and there are few cycle slips; and after a certain period of initialization and consistency verification, the integer is fixed through verification. A floating-point solution refers to the integer ambiguity not yet reliably fixed as an integer, or it has been fixed but cannot be maintained due to environmental or link deterioration. In this case, the integer ambiguity participates in the calculation in real number form, and its accuracy and stability are usually lower than those of a fixed solution. Floating-point solutions are commonly found in situations such as: excessive data delays, severe packet loss, or data interruptions; reduced satellite counts or deteriorating geometry; increased observation bias due to obstruction, multipath propagation, or non-line-of-sight conditions; cycle slips or carrier lock-up requiring reinitialization; and system startup, immediate link recovery, or high-dynamic vehicle phases. The solution state can switch between two states: when conditions improve, the floating-point solution can converge to a fixed solution; when conditions deteriorate, the fixed solution can degenerate into a floating-point solution.

[0028] In one example, "positioning uncertainty" is used to characterize the reliability of the current positioning result and can be understood as a statistical measure of positioning error. Positioning uncertainty can be obtained by the receiver or high-precision positioning module based on the observation residuals, error model, and estimated covariance during the solution process. It is usually output in the form of standard deviation and can be divided into horizontal uncertainty and vertical uncertainty. Horizontal uncertainty characterizes the magnitude of the vehicle's position error in the horizontal plane (e.g., east and north), while vertical uncertainty characterizes the magnitude of the elevation direction error. The smaller the positioning uncertainty, the more stable and reliable the positioning solution; the larger the positioning uncertainty, the greater the potential increase in positioning error or the solution being affected by abnormal observations, link anomalies, or other factors. Under ideal conditions (e.g., open environment, sufficient and geometrically sound satellites, high signal quality, continuous and low-delay differential correction data, few cycle slips, and a fixed solution obtained), positioning uncertainty is typically small: horizontal uncertainty can reach the centimeter level, for example, about 0.01–0.05 meters; vertical uncertainty is usually slightly larger than horizontal uncertainty, for example, about 0.02–0.10 meters. Under undesirable conditions (e.g., obstructions such as urban canyons, tree shade, or under bridges leading to enhanced multipath or non-line-of-sight effects, or increased latency, severe packet loss, or data interruption in differential correction data, resulting in floating-point solutions or degradation), positioning uncertainty increases significantly: horizontal uncertainty is typically in the decimeter to meter range, for example, approximately 0.2–2.0 meters; vertical uncertainty is typically even greater, in the decimeter to several meter range, for example, approximately 0.5–5.0 meters. In extreme cases (e.g., prolonged lack of differential correction data, insufficient available satellites, or severe observational anomalies), positioning uncertainty may continue to increase.

[0029] In one example, "cycle slip statistics" are used to characterize the continuity and reliability of carrier phase observations. A cycle slip refers to a loss of lock or a sudden phase change during satellite carrier phase tracking, resulting in one or more integer cycles (i.e., whole wavelength periods) of discontinuous change in carrier phase observations between adjacent epochs. Cycle slips directly disrupt the continuity of the carrier phase, requiring re-estimation of integer ambiguities, thereby reducing the ability to maintain a fixed solution and potentially causing the solution state to degenerate from a fixed solution to a floating-point solution. Therefore, this invention can count the number of cycle slips within a preset time window (e.g., 10 seconds, 30 seconds, or 60 seconds). The cycle slip statistics can be obtained from the receiver's baseband tracking status output (e.g., loss of lock indication, phase lock indication) or from a high-precision positioning module performing a consistency check on the carrier phase of adjacent epochs; the statistics can be counted on a per-satellite basis and summed to a total count. Under ideal conditions (e.g., open environment, high signal strength, weak multipath effect, well-installed antenna, stable vehicle dynamics, and stable differential correction data), carrier phase tracking is usually continuous, and the probability of cycle slips is low: within a 10-second time window, the cycle slip count is usually 0, or occasionally no more than 1. Under undesirable conditions (e.g., obstructions such as urban canyons, tree shade, under bridges, or elevated roads causing signal fading and multipath enhancement, or severe vehicle dynamics, electromagnetic interference, antenna obstruction / feeder problems, etc.), carrier phase tracking is more prone to loss of lock and cycle slips: within a 10-second time window, the cycle slip count may reach 2 to 10 or even higher; if continuous obstruction or frequent loss of lock occurs, the cycle slip count may further increase and be accompanied by a decrease in the number of available satellites, thereby significantly reducing the fixed solution hold-up rate and prolonging the fixed solution recovery time.

[0030] Step 2: Obtain differential correction data link quality information, which includes at least one of the following: differential correction data latency, packet loss rate, and outage events; In one example, differential correction data latency refers to the time difference between the generation (or timestamping) of differential correction data at the server and its reception and use for solution at the terminal. The smaller this latency, the better the match with the current observation epoch; as the latency increases, the correction information mismatches with the current observation, introducing additional residuals, reducing the reliability of integer ambiguity fixation, and increasing the risk of fixed solution drop. Under ideal conditions (e.g., stable cellular network, low link jitter, no significant congestion or retransmissions), differential correction data latency is typically low: generally 0.1–0.5 seconds, or no more than 1 second. Under less than ideal conditions (e.g., network congestion, weak signal, frequent base station switching, increased retransmissions, or short-term outages), differential correction data latency increases significantly: commonly reaching 2–5 seconds; when the latency further increases (e.g., exceeding 5–10 seconds), the effectiveness of the differential correction data for the current observation decreases significantly.

[0031] In one example, the packet loss rate is used to characterize the proportion of differential correction data packets that fail to arrive successfully or fail to arrive within a specified time limit within a preset time window (e.g., 10 seconds, 30 seconds, or 60 seconds). Packet loss causes discontinuous or incomplete correction information, leading to increased solution residuals, decreased fixed solution retention rate, increased reconnection frequency, and potentially inducing the degradation of fixed solutions to floating-point solutions. Under ideal conditions, the packet loss rate is typically low: approximately 0% within common time windows, or no more than 0.1% to 1%. Under non-ideal conditions, the packet loss rate can increase significantly: for example, reaching 1% to 10%. When the packet loss rate is consistently higher than 10% or accompanied by intermittent disconnections, the continuity of differential correction data is difficult to guarantee, fixed solutions are prone to frequent drops, and positioning uncertainty increases.

[0032] Step 3: Obtain scene and positioning requirement information, which includes at least one of the following: distance to the next turn or fork, road type, and road network complexity. In one example, the road network complexity can be calculated using the following steps: S1: Determine the statistical range: Using the vehicle's current location as the center, obtain the road network within a preset radius (e.g., a radius of 200 meters, 500 meters, or 1 kilometer) from the electronic map, or the road network within a preset driving distance ahead of the planned route (e.g., 500 meters or 1 kilometer ahead).

[0033] S2: Extract Topological Features: Within the statistical scope, extract the road topological features that influence driving decisions, including but not limited to: Number of intersections / forks (including "T-junctions, crossroads, roundabout entrances, forks, ramp divergence / merging points," etc.); Road hierarchy and morphological markers (e.g., whether there are interchanges, ramp groups, main and auxiliary roads, on-ramps and off-ramps, overpasses, etc.); Number of alternative paths (e.g., the number of branches available within the next driving distance); Road density and road spacing (e.g., dense distribution of parallel roads, auxiliary roads and main roads).

[0034] S3: Weighting and Summarizing: The above topological elements are summed according to preset weights to obtain the road network complexity value. Generally speaking, ramps, interchanges, and roundabouts have a greater impact on driving decisions and can be assigned higher weights; ordinary straight-through road sections have lower weights.

[0035] S4: Output format: The road network complexity can be output as a score (e.g., 0 to 100).

[0036] During road testing, the following numerical patterns generally apply to different types of roads: 1. Long straight sections of highways with long distances between entrances and exits: very few intersections / branches, simple topology, and road network complexity is usually 0 to 10.

[0037] 2. Ordinary urban main roads with large intersection spacing (e.g., one traffic light intersection every few hundred meters): There are a certain number of intersections but limited branching options, and the road network complexity is usually 10 to 30.

[0038] 3. Rural roads / county roads and branch roads have many intersections (e.g., multiple three-way intersections or forks in a short distance): The road network complexity is usually 30-60.

[0039] 4. Dense urban road network areas (e.g., grid roads in old urban areas, areas around commercial districts, and multiple parallel and branch roads): dense intersections, multiple route options, and road network complexity is usually 50-80.

[0040] 5. Interchanges / ramp groups / roundabouts or multi-level road intersections: These areas have multiple branching / merging routes and different levels of roads, resulting in the highest driver decision-making load and a road network complexity of 80-100.

[0041] In a specific numerical example, such as when a vehicle is traveling on a long straight section of a highway, the road network complexity can be calculated using the following steps: 1) Statistics window settings Spatial statistical range: 500 meters in radius around the vehicle's current location; Forward statistical range: 1000 meters ahead along the planned route (used to identify upcoming exits / diversions). Output format: Road network complexity score from 0 to 100.

[0042] 2) Topological features and statistical results (from electronic map) Within the above range, the following was extracted: Number of intersections (cross / T-junction, etc.): 0 Number of general branching / forks (excluding ramps): 0 Number of ramp divergence points (mainline exit / ramp branch): 0 Number of ramp merging points (ramp merging into mainline): 0 Interchange signs: None Roundabout sign: None Number of parallel roads / auxiliary roads (parallel to the main road and close to it): 1 Road network density level (roughly categorized by the number and spacing of roads on the map): Low 3) Weighting and scoring rules for each item This embodiment uses the following weights: Ramp divergence points: 20 points for each one. Ramp merging points: 15 points for each one. Interchange sign: 30 points will be awarded for its appearance. At-grade intersections: 5 points for each intersection. General forks / branches: 8 points for each one. Parallel roads / auxiliary roads: 3 points for each one. Road network density level: Low is scored as 2 points, Medium as 8 points, High as 15 points And set an upper limit: the final road network complexity score shall not exceed 100 points.

[0043] 4) Calculation process and complexity results Contribution from ramp divergence point: 0 × 20 = 0 Contribution from ramp merging point: 0 × 15 = 0 Interchange contribution: None (0) Contribution from the intersection: 0 × 5 = 0 General branch road contribution: 0 × 8 = 0 Contribution from parallel roads / auxiliary roads: 1 × 3 = 3 Road network density contribution: low (2) Adding all the terms together, we get the network complexity: 0 + 0 + 0 + 0 + 0 + 3 + 2 = 5 points.

[0044] The results indicate that the road segment has a simple topology.

[0045] Step 4: Based on vehicle positioning information, differential correction data link quality information, and scenario and positioning requirements information, determine the vehicle's state from high-precision state, hold state, data-saving state, and degradation state.

[0046] In a preferred embodiment, the method further includes: If the vehicle is confirmed to be in high-precision mode, differential correction data is received at a high frequency; in one example, receiving differential correction data at a high frequency means receiving differential correction data at a frequency of 1 to 5 times per second; once the vehicle is in high-precision mode, the navigation system can notify the driver on the vehicle's infotainment screen that the vehicle navigation is currently in high-precision mode, such as... Figure 4 As shown; If the vehicle is confirmed to be in hold mode, differential correction data is received at a low to medium frequency. In one example, differential correction data is received at a frequency of once per second. Once the vehicle is in hold mode, the navigation system can notify the driver on the vehicle's infotainment screen that the navigation is currently in hold mode. Figure 5As shown; those skilled in the art should understand that if it is determined that the vehicle is not in a degraded state, nor in a high-precision state, nor in a power-saving state, it can be determined that the vehicle has entered a holding state; If it is determined that the vehicle has entered the flow-saving state, differential correction data is received at a low frequency or in an event-triggered manner. In one example, receiving differential correction data at a low frequency means receiving differential correction data once every 2 to 5 seconds. In another example, receiving differential correction data in an event-triggered manner means that when a preset event is detected, reception is started immediately or the reception frequency is temporarily increased within a preset time window to balance flow saving and positioning stability at critical moments. Triggering events include, but are not limited to: 1) Navigation key point proximity event: the distance to the next turn / fork / ramp / exit is less than a preset distance threshold; 2) Road network complexity increase event: the road network complexity exceeds a preset threshold or increases sharply within a short time window; 3) Solution state degradation event: a fixed solution becomes a floating-point solution, differential code positioning, or single-point positioning; 4) Positioning uncertainty anomaly event: horizontal or vertical positioning uncertainty exceeds a threshold or increases suddenly; 5) Frequent cycle slip event: the number of cycle slips exceeds a threshold within a preset time window; 6) Satellite condition deterioration event: the number of satellites participating in the solution is lower than a threshold or the geometric strength index deteriorates significantly; 7) Link recovery event: data latency is corrected, packet loss rate decreases, or the disconnection ends and continuous availability reaches a preset duration. After triggering, the system can switch to hold / high precision mode. When the vehicle enters the data-saving mode, the navigation system can prompt the driver on the vehicle interface that the vehicle navigation is currently in the data-saving mode, such as... Figure 6 As shown; If the vehicle is determined to have entered a degraded state, a protection strategy is implemented and a conservative positioning quality warning is output. In one example, in this invention, the degraded state is used to ensure navigation continuity and reduce the risk of positioning jumps misleading the user when differential correction data is unavailable or link quality is insufficient (e.g., excessive latency, severe packet loss, or disconnection). After entering the degraded state, the vehicle system stops relying on differential correction data to achieve a fixed solution, does not force expired or incomplete correction data for high-precision calculations, and can downgrade the positioning calculation mode to a floating-point solution; at the same time, it maintains communication reconnection and recovery management, records the disconnection duration, latency, and packet loss rate, and triggers exit from the degraded state and switches to a hold-at-home state or a high-precision state when it detects that the correction data is continuously available for a preset duration and the link indicators have recovered to within the threshold range. In a degraded state, the vehicle's infotainment system adopts a conservative approach to positioning output. This includes increasing the uncertainty of the positioning output and smoothing or limiting position, heading, and speed to suppress jumps caused by short-term anomalies. The navigation guidance strategy is adjusted accordingly, reducing reliance on lane-level or fine-tuned turn points and employing more conservative prompts (such as advance warnings and increased turn trigger radius). Forced turn decisions can be temporarily suspended near complex road networks or key points. As an optional implementation, multi-source sensor-assisted positioning can be enabled in a degraded state to maintain short-term relative accuracy and trajectory continuity. This includes using inertial measurement units to calculate displacement and heading changes, using wheel speed / mileage information for displacement constraints, using vehicle kinematic constraints to suppress lateral drift, and combining map matching to constrain the positioning results to the road network. Through these measures, continuous, usable, and less misleading navigation output can be provided during differential unavailability periods, and a smooth switchback to high-precision positioning can be achieved after the link is restored. When the vehicle enters a degraded state, the navigation system can prompt the driver on the vehicle's infotainment interface that the vehicle navigation is currently in a degraded state. Figure 7 As shown.

[0047] In a preferred embodiment, the solution states include at least: fixed solutions and floating-point solutions.

[0048] In a preferred embodiment, the vehicle is determined to have entered a high-precision state if at least one of the following conditions is met: The distance between the vehicle and the next turn or fork is less than a preset key point distance threshold. In one example, the preset key point distance threshold can be set as a configurable parameter based on road type, vehicle speed, and navigation prompt advance. Preferably, in low-speed scenarios such as urban or rural roads, the preset key point distance threshold can be approximately 300–800 meters; in high-speed scenarios such as highways, to cover the advance requirements for entrance / exit and ramp guidance, the preset key point distance threshold can be approximately 800–1500 meters. In a further preferred embodiment, the threshold can be adaptively adjusted with vehicle speed: a smaller threshold is used when the vehicle speed is low, and a larger threshold is used when the vehicle speed is high, to ensure that the trigger time advance is within a preset range (e.g., 10–30 seconds in advance).

[0049] Vehicles enter ramps, entrances / exits, or interchange areas. In one example, the determination of "entering a ramp, entrance / exit, or interchange area" can be based on electronic maps and navigation path information. Specifically, the vehicle system reads road attributes and topological markers from map data to identify whether there are ramp edges, entrance / exit connection edges, or interchange nodes within the current road or a preset forward distance range. When the vehicle's location point (or the road segment matched on the map) falls into a road segment marked as a ramp / entrance / exit / interchange, or when the distance from the vehicle to the nearest ramp divergence point, merging point, or entrance / exit node is less than a second preset distance threshold (e.g., 50-300 meters), it is determined that the vehicle has entered a ramp, entrance / exit, or interchange area. To improve robustness, forward prediction can be performed in conjunction with the action type of the navigation path (e.g., "exiting the main road" or "entering a ramp"): when the navigation indication indicates an entry / exit action within a preset distance, it is determined in advance that the vehicle has entered the above-mentioned area and triggers a high-precision state. The aforementioned thresholds and judgment rules can be stored as configurable parameters in the vehicle system, and can be switched frequently at the boundary through time window smoothing and minimum dwell time suppression.

[0050] The solution is a floating-point solution; The road network complexity exceeds a preset threshold. In one example, the preset threshold for road network complexity can be set to 60 or 80.

[0051] In a preferred embodiment, the vehicle is determined to be in a flow-saving state if all of the following conditions are met: The solution state is a fixed solution and the time during which the solution state remains a fixed solution reaches a preset time threshold. The weekly slip count is below the preset weekly slip count threshold; The differential correction data latency is lower than the preset differential correction data latency threshold; and The packet loss rate is lower than the preset packet loss rate threshold. In one example, the preset time threshold (duration of the fixed solution) is preferably 180 seconds (which can be 60-300 seconds). The fact that the fixed solution lasts for a period of time indicates that the integer ambiguity has been stabilized and the observation environment is good. At this time, it is less likely to lose the fixed solution when the correction receiving frequency is reduced.

[0052] Preset cycle slip statistics threshold (number of cycle slips within a time window): The statistics window is 10 seconds, and the preferred threshold is ≤0 times (≤1 time / 10 seconds is acceptable). Cycle slips reflect carrier phase discontinuities. Very few or zero cycle slips indicate stable carrier tracking, and the risk of maintaining a fixed solution is low after entering the flow-saving phase.

[0053] The preset differential correction data delay threshold is preferably ≤1 second (can be ≤0.5 to 1.5 seconds). A small correction delay indicates that the correction information matches the current observation epoch well, and the correction effectiveness can still be maintained even after reducing the receiving frequency.

[0054] Preset packet loss rate threshold: with a statistical window of 60 seconds, preferably ≤1% (can be ≤0.1%~2%). A low packet loss rate means good continuity of corrected data, and less likely to cause sudden supply interruptions and dropouts after entering the data saving phase.

[0055] The consistent stability of the fixed solution, the minimal cycle slips, the low correction delay, and the low packet loss rate all indicate that "demand is not urgent and capacity is sufficient." Under these circumstances, the system is in a high-confidence positioning phase, and temporarily reducing the correction receiving frequency usually does not immediately disrupt the fixed integer ambiguity and trajectory continuity, thereby reducing communication traffic consumption without significantly reducing navigation availability.

[0056] In a preferred embodiment, the vehicle is determined to have entered a degradation state if at least one of the following conditions is met: The duration for which differential correction data has not been received has reached a preset duration threshold; The differential correction data delay exceeds the preset unavailable threshold; The packet loss rate exceeds the preset packet loss rate threshold within the preset time window; The positioning uncertainty exceeds a preset uncertainty threshold. In one example, the preset duration threshold (the duration for which no correction data has been received) is preferably 3 seconds (2 to 5 seconds is acceptable). Several consecutive seconds without correction data usually leads to the expiration of correction information, a significant decrease in the ability to retain the fixed solution, and should trigger degradation protection.

[0057] Preset unavailability threshold (correcting unavailability due to data delay): preferably ≥5 seconds (≥5~10 seconds is acceptable). When the delay is too large, the correction and observation will be severely mismatched, and continuing to rely on high-precision solutions may introduce the risk of jumps, so it is advisable to degrade.

[0058] Packet loss rate threshold (degradation judgment): The statistical window is 30 seconds, preferably ≥10% (≥8%~15% is acceptable). Sustained high packet loss will lead to discontinuous corrections, which will easily trigger frequent drops of fixed solutions and should enter degradation.

[0059] Preset uncertainty threshold: Preferably, the horizontal positioning uncertainty is ≥1.0 meter or the vertical positioning uncertainty is ≥2.0 meter (horizontal uncertainty can be 0.5–2.0 meters, vertical uncertainty can be 1.0–5.0 meters). A significant increase in uncertainty indicates a decrease in positioning reliability, requiring more conservative quality prompts and the adoption of a degraded navigation strategy.

[0060] This invention provides a high-precision positioning system for outdoor scenes that integrates BeiDou signals. The system includes a high-precision positioning module, which is configured to perform the following operations: Obtain vehicle location-related information, which includes at least one of the following: solution state, location uncertainty, and cycle slip statistics; Obtain differential correction data link quality information, which includes at least one of the following: differential correction data latency, packet loss rate, and outage events; Obtain scene and positioning requirement information, which includes at least one of the following: distance to the next turn or fork, road type, and road network complexity; and Based on location-related information, link quality information, and scenario and location requirements information, the vehicle is determined to enter one of the following states: high-precision state, hold state, data-saving state, and degradation state.

[0061] In a preferred embodiment, the high-precision positioning module is further configured to perform the following operations: If it is determined that the vehicle has entered a high-precision state, differential correction data is received in a high-frequency manner; If it is determined that the vehicle has entered hold mode, differential correction data is received in a low-to-medium frequency manner; If it is determined that the vehicle has entered the flow-saving state, differential correction data is received at low frequency or in an event-triggered manner; If the vehicle is determined to be in a degraded state, a protection strategy is implemented and a conservative positioning quality warning is output.

[0062] In a preferred embodiment, the solution states include at least: fixed solutions and floating-point solutions.

[0063] In a preferred embodiment, the vehicle is determined to have entered a high-precision state if at least one of the following conditions is met: The distance between the vehicle and the next turn or fork is less than a preset key point distance threshold; Vehicles enter ramps, entrances / exits, or interchange areas; The solution is a floating-point solution; The road network complexity exceeds the preset threshold.

[0064] Unless otherwise expressly defined, expressions such as "including / comprises" and "having" in this specification are open-ended terms, meaning "including but not limited to"; references such as "first" and "second" are only used to distinguish different objects and do not indicate order, importance, or quantity; "and / or" indicates any one of the listed elements or any combination thereof; quantitative descriptions such as "a," "at least one," and "multiple" should not be construed as unnecessary limitations. The functional modules, units, or components described in this disclosure can be implemented using hardware, software, firmware, or any combination thereof, for example, by processor executing instructions, or by dedicated circuits (such as application-specific integrated circuits, field-programmable gate arrays, digital signal processors, etc.). Module division is only for ease of description, and related functions can be migrated, merged, or split between different modules. The method steps described can be executed in the order of the examples, or adjusted without violating the technical logic and without affecting the implementation effect, including changing the order, parallel / overlapping execution, repeated execution, or omitting non-critical steps; unless otherwise expressly stated, the order of steps should not be interpreted as a limitation.

[0065] The present disclosure has been described above with reference to specific embodiments. Those skilled in the art should understand that modifications, substitutions, combinations, reconstructions, or equivalent changes can be made to the above embodiments without departing from the basic ideas and technical essence disclosed in this disclosure. All technical solutions not listed individually in the specification but falling within the scope of the appended claims and their equivalents should be considered to fall within the protection scope of this disclosure; the embodiments described in the specification are for illustrative purposes only and do not constitute a limitation on the scope of protection of the claims.

Claims

1. A high-precision positioning method for outdoor scenes integrating BeiDou signals, wherein the method is executed by a high-precision positioning module, comprising: Obtain vehicle positioning-related information, which includes at least one of the following: solution state, positioning uncertainty, and cycle slip statistics; Obtain differential correction data link quality information, which includes at least one of differential correction data latency, packet loss rate, and outage events; Obtain scene and positioning requirement information, which includes at least one of the following: distance to the next turn or fork, road type, and road network complexity; and Based on the vehicle positioning information, the differential correction data link quality information, and the scenario and positioning requirement information, the vehicle is determined to enter one of the following states: high-precision state, hold state, data-saving state, and degradation state.

2. The method according to claim 1, wherein, The method further includes: If it is determined that the vehicle has entered the high-precision state, differential correction data is received in a high-frequency manner; If it is determined that the vehicle has entered the holding state, the differential correction data is received in a low-to-medium frequency manner; If it is determined that the vehicle has entered the flow-saving state, the differential correction data is received in a low-frequency or event-triggered manner; If it is determined that the vehicle has entered the degraded state, a protection strategy is executed and a conservative positioning quality warning is output.

3. The method according to claim 1, wherein, The solution states include at least: fixed solutions and floating-point solutions.

4. The method according to claim 3, wherein, The vehicle is determined to have entered the high-precision state if at least one of the following conditions is met: The distance between the vehicle and the next turn or fork is less than a preset key point distance threshold; The vehicle enters the ramp, entrance / exit, or interchange area; The solution state is a floating-point solution; The road network complexity exceeds a preset threshold.

5. The method according to claim 3, wherein, If all of the following conditions are met, the vehicle is determined to enter the flow-saving state: The time during which the solution state is the fixed solution and the solution state is maintained as the fixed solution reaches a preset time threshold. The cycle slip statistics are lower than the preset cycle slip statistics threshold; The differential correction data delay is lower than a preset differential correction data delay threshold; and The packet loss rate is lower than the preset packet loss rate threshold.

6. The method according to claim 1, wherein, The vehicle is determined to have entered the degradation state if at least one of the following conditions is met: The duration for which the differential correction data has not been received reaches a preset duration threshold; The differential correction data delay exceeds a preset unavailable threshold; The packet loss rate exceeds a preset packet loss rate threshold within a preset time window; The positioning uncertainty exceeds a preset uncertainty threshold.

7. A high-precision positioning system for outdoor scenes integrating BeiDou signals, the system comprising a high-precision positioning module configured to perform the following operations: Obtain vehicle location-related information, which includes: At least one of the following: solution state, positioning uncertainty, and cycle slip statistics; Obtain differential correction data link quality information, which includes at least one of differential correction data latency, packet loss rate, and outage events; Obtain scene and positioning requirement information, which includes at least one of the following: distance to the next turn or fork, road type, and road network complexity; and Based on the vehicle positioning information, the differential correction data link quality information, and the scenario and positioning requirement information, the vehicle is determined to enter one of the following states: high-precision state, hold state, data-saving state, and degradation state.

8. The system according to claim 7, wherein, The high-precision positioning module is also configured to perform the following operations: If it is determined that the vehicle has entered the high-precision state, differential correction data is received in a high-frequency manner; If it is determined that the vehicle has entered the holding state, the differential correction data is received in a low-to-medium frequency manner; If it is determined that the vehicle has entered the flow-saving state, the differential correction data is received in a low-frequency or event-triggered manner; If it is determined that the vehicle has entered the degraded state, a protection strategy is executed and a conservative positioning quality warning is output.

9. The system according to claim 8, wherein, The solution states include at least: fixed solutions and floating-point solutions.

10. The method according to claim 9, wherein, The vehicle is determined to have entered the high-precision state if at least one of the following conditions is met: The distance between the vehicle and the next turn or fork is less than a preset key point distance threshold; The vehicle enters the ramp, entrance / exit, or interchange area; The solution state is a floating-point solution; The road network complexity exceeds a preset threshold.

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