Device and method for acquiring position of vehicle terminal

Abstract

The invention relates to the technical field of vehicle positioning, in particular to a device and a method for acquiring the position of a vehicle terminal, which are characterized in that by combining Beidou positioning, an inertial navigation system and lora communication, when a target vehicle is in a signal abnormal area and has a fault or is parked due to an accident, the position of the target vehicle is acquired through multiple lora communication between the other passing vehicles and the target vehicle; recording the communication signal intensity of each time, when the vehicle leaves the signal abnormal area, obtaining the position of the vehicle when receiving and transmitting lora signals according to the acceleration and angular velocity information recorded by the inertial navigation system in the area and the Beidou positioning after the vehicle leaves, and then calculating the position of the target vehicle. Compared with an existing method, the method can accurately obtain the accurate position of the accident parking vehicle in areas such as canyons, forests and tunnels, support is provided for vehicle rescue, meanwhile, signal speed measurement, track correction and the like can be carried out under the condition that the vehicle does not have 4G / 5G signals, other equipment does not need to be additionally arranged in the areas, and practicability is high.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle positioning, and in particular to a device and method for acquiring a vehicle terminal position. Background Art

[0002] The Beidou satellite navigation system determines the three-dimensional coordinates (longitude, latitude and altitude) of the vehicle on the earth by receiving signals from multiple satellites. However, when the vehicle travels to canyons, forests, high-rise buildings and other areas that affect signal transmission, the accuracy of Beidou positioning may decrease or cause signal interruption, especially when the vehicle travels in an area with weak signals. It is often difficult to accurately locate the vehicle's parking position due to signal isolation. Summary of the invention

[0003] In view of this, an object of the present invention is to provide a device and method for obtaining a vehicle terminal position, so as to solve the problem that the existing method is difficult to accurately locate vehicles in areas with weak signals.

[0004] Based on the above purpose, the present invention provides a method for obtaining a vehicle terminal position, comprising the following steps:

[0005] S1. Obtain the location information of the target vehicle A through Beidou positioning, and determine whether the positioning is interrupted or the positioning accuracy is reduced. If the positioning is interrupted or the positioning accuracy is reduced, execute step S3, otherwise execute step S2;

[0006] S2, determine whether the current position of the vehicle is in a pre-defined signal abnormal area, if so, execute step S3, otherwise return the acquired vehicle position information;

[0007] S3, obtain the LoRa communication information between the target vehicle A and any surrounding vehicle B, and intercept the LoRa signal strength between vehicle A and vehicle B at multiple different time points t1~tn;

[0008] S4, obtaining acceleration and angular velocity information of vehicle B through the vehicle inertial navigation system;

[0009] S5. When vehicle B leaves the signal abnormality area, the location information of vehicle B is obtained through Beidou positioning, and the location of vehicle B at time points t1 to tn is calculated based on the acceleration and angular velocity information of vehicle B;

[0010] S6. Calculate the position of vehicle A based on the calculated position of vehicle B at time points t1-tn and the lora signal strength with vehicle A at time points t1-tn.

[0011] Preferably, the signal abnormality area includes but is not limited to a canyon area, a forest area, a tunnel area, and an area with densely populated high-rise buildings.

[0012] Preferably, acquiring the position information of the target vehicle A through Beidou positioning includes positioning the target vehicle A through Beidou b1i, Beidou b1c or Beidou b2a frequency band.

[0013] Preferably, in step S3, the number of lora signal intensities captured at different time points is at least 3.

[0014] Preferably, in step S6, calculating the position of vehicle A includes:

[0015] Based on the acceleration and angular velocity information of vehicle B, the positions of vehicle B at time points t1, t2, and t3 are determined as (x A ,y A ), (x B ,y B ), (x C ,y C ), the signal strengths measured at three time points are RSSI A , RSSI A , RSSI C ;

[0016] According to the signal propagation model PL(d)=PL(d0)+10nlog(d / d0), the distance d from the vehicle to the three gateways is estimated. A d B d C , where PL(d) is the path loss at distance , PL(d0) is the path loss at reference distance d0, and n is the path loss exponent;

[0017] The position of target vehicle A is calculated by trilateration.

[0018] Preferably, the formula for trilateration is:

[0019] (xx A ) 2 +(yy A ) 2 =d A 2 ;

[0020] (xx B ) 2 +(yy B ) 2 =d B 2 ;

[0021] (xx B ) 2 +(yy B ) 2 =d B 2 ;

[0022] Solving this equation yields the position coordinates (x, y) of vehicle A.

[0023] The present invention also provides a device for obtaining a vehicle terminal position, comprising:

[0024] Beidou positioning system, used to obtain the location information of target vehicle A;

[0025] A judgment module is used to judge whether there is a positioning interruption or a decrease in positioning accuracy, and whether the current position of the vehicle is in a pre-defined signal abnormality area;

[0026] The Lora communication module includes a Lora transceiver unit installed on the target vehicle A and any vehicle B, which is used to obtain the Lora communication information between the target vehicle A and any surrounding vehicle B, and intercept the Lora signal strength between the vehicle A and the vehicle B at multiple different time points t1 to tn;

[0027] A vehicle inertial navigation system, used to obtain acceleration and angular velocity information of vehicle B through the vehicle inertial navigation system;

[0028] The calculation module is used to obtain the position information of vehicle B through Beidou positioning when vehicle B drives out of the signal abnormal area, and calculate the position of vehicle B at time points t1-tn according to the acceleration and angular velocity information of vehicle B, and calculate the position of vehicle A according to the calculated position of vehicle B at time points t1-tn and the lora signal strength with vehicle A at time points t1-tn. The beneficial effects of the present invention: the present invention combines Beidou positioning, inertial navigation system and lora communication. When the target vehicle is in a signal abnormal area and fails or stops due to an accident, the target vehicle can be obtained through multiple collisions with the target vehicle by other vehicles passing by. LoRa communication records the strength of each communication signal. When the vehicle leaves the signal abnormal area, the acceleration and angular velocity information recorded by the vehicle's inertial navigation system in the area is combined with the Beidou positioning after leaving to obtain the position of the vehicle when sending and receiving LoRa signals. Then the position of the target vehicle is calculated. Compared with the existing methods, it can accurately obtain the exact position of accident parked vehicles in canyons, forests, tunnels and other areas, and provide support for vehicle rescue. At the same time, it also has the function of signal speed measurement and trajectory correction when the vehicle has no 4G / 5G signal. This method does not require the deployment of other equipment in these areas, and is very practical. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only for the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0030] Figure 1 The present invention is a flowchart of a method for obtaining a vehicle terminal position according to an embodiment of the present invention. DETAILED DESCRIPTION

[0031] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments.

[0032] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0033] like Figure 1 As shown, the embodiment of this specification provides a method for obtaining the position of a vehicle terminal, comprising the following steps:

[0034] S1. Obtain the location information of the target vehicle A through Beidou positioning, and determine whether the positioning is interrupted or the positioning accuracy is reduced. If the positioning is interrupted or the positioning accuracy is reduced, execute step S3, otherwise execute step S2. Specifically, the target vehicle A can be positioned through Beidou b1i, Beidou b1c or Beidou b2a frequency bands. Beidou supports three frequency bands, single Beidou b1i, b1c, b2a, which can support both domestic and global.

[0035] S2. Determine whether the current position of the vehicle is in a pre-defined signal abnormality area. If so, execute step S3; otherwise, return the acquired vehicle position information. Specifically, the signal abnormality area can be pre-defined by information such as longitude and latitude. Generally speaking, the signal abnormality area includes canyon areas, forest areas, tunnel areas, high-rise building dense areas, etc. Since the Beidou signal is easily blocked in these areas, resulting in inaccurate positioning or signal interruption, the following steps are required for positioning.

[0036] S3. Obtain the LoRa communication information between the target vehicle A and any surrounding vehicle B, and intercept the LoRa signal strength (RSSI, Received Signal Strength Indication) between vehicle A and vehicle B at multiple different time points t1~tn. RSSI is the received signal strength indication. LoRa can measure the signal strength when receiving a signal from a terminal device. There is a certain relationship between signal strength and distance. Generally speaking, the farther the distance, the weaker the signal strength.

[0037] S4, obtaining acceleration and angular velocity information of vehicle B through the vehicle inertial navigation system;

[0038] S5. When vehicle B leaves the signal abnormality area, the location information of vehicle B is obtained through Beidou positioning, and the location of vehicle B at time points t1 to tn is calculated based on the acceleration and angular velocity information of vehicle B. Specifically, the original data of Beidou and inertial navigation systems (such as Beidou's pseudorange, pseudorange rate and inertial navigation's acceleration, angular velocity, etc.) are fused. For example, the data of Beidou and inertial navigation are fused through the Kalman filter algorithm. Kalman filtering can dynamically assign weights based on the reliability of the two types of data. Thus, the location of vehicle B at time points t1 to tn is calculated.

[0039] S6. Calculate the position of vehicle A based on the calculated position of vehicle B at time points t1-tn and the lora signal strength with vehicle A at time points t1-tn.

[0040] As an implementation manner, in step S3, the number of lora signal strength interceptions at different time points is at least 3.

[0041] In step S6, calculating the position of vehicle A includes:

[0042] Based on the acceleration and angular velocity information of vehicle B, the positions of vehicle B at time points t1, t2, and t3 are determined as (x A ,y A ), (x B ,y B ), (x C ,y C), the signal strengths measured at three time points are RSSI A , RSSI A , RSSI C ;

[0043] According to the signal propagation model PL(d)=PL(d0)+10nlog(d / d0), the distance d from the vehicle to the three gateways is estimated. A ,d B ,d C , where PL(d) is the path loss at distance , PL(d0) is the path loss at reference distance d0, and n is the path loss exponent;

[0044] The position of target vehicle A is calculated by trilateration.

[0045] The formula for trilateration is:

[0046] (xx A ) 2 +(yy A ) 2 =d A 2 ;

[0047] (xx B ) 2 +(yy B ) 2 =d B 2 ;

[0048] (xx B ) 2 +(yy B ) 2 =d B 2 ;

[0049] Solving this equation yields the position coordinates (x, y) of vehicle A.

[0050] As an implementation method, the method can also perform signal speed measurement and trajectory correction when the target vehicle A has no 4G / 5G signal.

[0051] The embodiment of this specification also provides a device for obtaining a vehicle terminal position, including:

[0052] Beidou positioning system, used to obtain the location information of target vehicle A;

[0053] A judgment module is used to judge whether there is a positioning interruption or a decrease in positioning accuracy, and whether the current position of the vehicle is in a pre-defined signal abnormality area;

[0054] The Lora communication module includes a Lora transceiver unit installed on the target vehicle A and any vehicle B, which is used to obtain the Lora communication information between the target vehicle A and any surrounding vehicle B, and intercept the Lora signal strength between the vehicle A and the vehicle B at multiple different time points t1 to tn;

[0055] A vehicle inertial navigation system, used to obtain acceleration and angular velocity information of vehicle B through the vehicle inertial navigation system;

[0056] The calculation module is used to obtain the position information of vehicle B through Beidou positioning when vehicle B drives out of the signal abnormality area, and calculate the position of vehicle B at time points t1~tn according to the acceleration and angular velocity information of vehicle B, and calculate the position of vehicle A according to the calculated position of vehicle B at time points t1~tn and the lora signal strength with vehicle A at time points t1~tn.

[0057] The present invention combines Beidou positioning, inertial navigation system and LoRa communication. When a target vehicle breaks down or stops for an accident in a signal abnormality area, other vehicles passing by communicate with the target vehicle for many times through LoRa, and record the strength of each communication signal. When the vehicle leaves the signal abnormality area, the position of the vehicle when receiving and sending LoRa signals is obtained according to the acceleration and angular velocity information recorded by the inertial navigation system of the vehicle in the area, combined with Beidou positioning after leaving, and then the position of the target vehicle is calculated. Compared with the existing method, the accurate position of the accident-parked vehicle in areas such as canyons, forests, and tunnels can be accurately obtained, so as to provide support for vehicle rescue. Moreover, the present invention does not need to arrange other equipment in these areas, and is very practical.

[0058] Those skilled in the art should understand that the discussion of any of the above embodiments is only exemplary and is not intended to imply that the scope of the present invention is limited to these examples; under the concept of the present invention, the technical features in the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other changes in different aspects of the present invention as described above, which are not provided in detail for the sake of simplicity. Any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for obtaining a vehicle terminal position, characterized in that: The following steps are involved: S1. Obtain the location information of the target vehicle A through Beidou positioning, and determine whether the positioning is interrupted or the positioning accuracy is reduced. If the positioning is interrupted or the positioning accuracy is reduced, execute step S3, otherwise execute step S2; S2, determine whether the current position of the vehicle is in a pre-defined signal abnormal area, if so, execute step S3, otherwise return the acquired vehicle position information; S3, obtain the LoRa communication information between the target vehicle A and any surrounding vehicle B, and intercept the LoRa signal strength between vehicle A and vehicle B at multiple different time points t1~tn; S4, obtaining acceleration and angular velocity information of vehicle B through the vehicle inertial navigation system; S5. When vehicle B leaves the signal abnormality area, the location information of vehicle B is obtained through Beidou positioning, and the location of vehicle B at time points t1 to tn is calculated based on the acceleration and angular velocity information of vehicle B; S6. Calculate the position of vehicle A based on the calculated position of vehicle B at time points t1-tn and the lora signal strength with vehicle A at time points t1-tn.

2. The method for obtaining the vehicle terminal position according to claim 1, characterized in that: The signal abnormality areas include but are not limited to canyon areas, forest areas, tunnel areas, and areas with densely populated high-rise buildings.

3. The method for obtaining the vehicle terminal position according to claim 1, characterized in that: The obtaining of the position information of the target vehicle A through Beidou positioning includes positioning the target vehicle A through Beidou b1i, Beidou b1c or Beidou b2a frequency band.

4. The method for obtaining the vehicle terminal position according to claim 1, characterized in that: In step S3, the number of LoRa signal intensities captured at different time points is at least 3.

5. The method for obtaining the vehicle terminal position according to claim 4, characterized in that: In step S6, calculating the position of vehicle A includes: Based on the acceleration and angular velocity information of vehicle B, the positions of vehicle B at time points t1, t2, and t3 are determined as (x A ,y A ), (x B ,y B ), (x C ,y C ), the signal strengths measured at three time points are RSSI A , RSSI A , RSSI C ; According to the signal propagation model PL(d)=PL(d0)+10nlog(d / d0), the distance d from the vehicle to the three gateways is estimated. A ,d B ,d C , where PL(d) is the path loss at distance , PL(d0) is the path loss at reference distance d0, and n is the path loss exponent; The position of target vehicle A is calculated by trilateration.

6. The method for obtaining the vehicle terminal position according to claim 5, characterized in that: The formula for the trilateration method is: (x-x A ) 2 +(y-y A ) 2 =d A 2 ; (x-x B ) 2 +(y-y B ) 2 =d B 2 ; (x-x B ) 2 +(y-y B ) 2 =d B 2 ; Solving this equation yields the position coordinates (x, y) of vehicle A.

7. A device for obtaining a vehicle terminal position, characterized in that: include: Beidou positioning system, used to obtain the location information of target vehicle A; A judgment module is used to judge whether there is a positioning interruption or a decrease in positioning accuracy, and whether the current position of the vehicle is in a pre-defined signal abnormality area; The Lora communication module includes a Lora transceiver unit installed on the target vehicle A and any vehicle B, which is used to obtain the Lora communication information between the target vehicle A and any surrounding vehicle B, and intercept the Lora signal strength between the vehicle A and the vehicle B at multiple different time points t1 to tn; A vehicle inertial navigation system, used to obtain acceleration and angular velocity information of vehicle B through the vehicle inertial navigation system; The calculation module is used to obtain the position information of vehicle B through Beidou positioning when vehicle B drives out of the signal abnormality area, and calculate the position of vehicle B at time points t1~tn according to the acceleration and angular velocity information of vehicle B, and calculate the position of vehicle A according to the calculated position of vehicle B at time points t1~tn and the lora signal strength with vehicle A at time points t1~tn.

Images