HK1237407B - Method and device for matching track points acquired by positioning system into map - Google Patents

Description

Method and device for matching trajectory points collected by positioning system to map

Technical Field

The present invention relates to the field of positioning and navigation, and in particular to a method and device for matching trajectory points collected by a positioning system to a map.

Background Art

Navigation systems are now widely installed in cars. However, due to the accuracy of the car navigation system itself and the surrounding environment, the GNSS positioning results directly obtained by positioning systems (such as the Global Positioning System (GPS) or the Beidou Positioning System) are often not on the actual road the vehicle is traveling (such as the road shown on the vehicle's electronic map). Therefore, map matching technology is needed to convert the acquired track points into a path in real time or through post-processing to achieve real-time navigation and historical track playback.

Existing map matching technologies include incremental calculation techniques or global calculation techniques. Incremental calculation techniques often use the relationship between all candidate locations of the most recently acquired GNSS trajectory point and the previous trajectory point to select the candidate location point with the highest probability as the matching result. The matching result is then selected based on the relationship between the obtained matching result and all candidate locations of the next trajectory point, and the process is repeated. Global calculation techniques combine all candidate locations of all trajectory points on the trajectory obtained from the positioning system, calculate the probability of each combination, and select the candidate location point combination with the highest probability as the map matching result for the entire trajectory.

The incremental calculation method mentioned above requires a smaller computer and is faster, but because it only considers the relationship between the current point and the next point, the matching accuracy is low. Matching errors are also easily propagated to subsequent trajectory points, resulting in even greater matching errors. The global calculation method, on the other hand, considers all possible candidate position combinations, resulting in a higher matching accuracy, but requires a larger computer and is slower.

Therefore, a map matching technology is needed that can significantly improve the accuracy of map matching while maintaining a low computational complexity.

Summary of the Invention

In order to solve at least some of the above problems, embodiments of the present invention provide a method and apparatus for matching trajectory points collected by a positioning system to a map, so as to achieve improvements in computational complexity and accuracy.

According to one solution of an embodiment of the present invention, a method for matching trajectory points collected by a positioning system to a map is provided, comprising:

Obtain one or more first candidate location points of the first trajectory point on the map;

Obtain one or more second candidate location points of a second trajectory point on the map, wherein the second trajectory point is a trajectory point after the first trajectory point on the trajectory;

Calculating a first occurrence probability of each first candidate location point and each second candidate location point;

For each first candidate position point, selecting a second candidate position point having a maximum first occurrence probability therewith as a temporary matching point of the second trajectory point corresponding to each first candidate position point;

Calculating a second occurrence probability of a temporary matching point corresponding to each first candidate position point for a current matching position point, each first candidate position point, and the second trajectory point, wherein the current matching position point is a matching position point on the map of a trajectory point that precedes the first trajectory point on the trajectory; and

The first candidate position with the largest second occurrence probability is selected as the new current matching position point.

According to another embodiment of the present invention, there is provided an apparatus for matching trajectory points collected by a positioning system to a map, comprising:

a candidate location point acquirer, configured to acquire one or more first candidate location points of the first trajectory point on the map, and to acquire one or more second candidate location points of the second trajectory point on the map, wherein the second trajectory point is a trajectory point subsequent to the first trajectory point on the trajectory;

an occurrence probability calculator, configured to calculate a first occurrence probability of each first candidate location point and each second candidate location point; and

a matching point determiner, configured to select, for each first candidate position point, a second candidate position point having a maximum first occurrence probability therewith as a temporary matching point of the second trajectory point corresponding to each first candidate position point;

wherein the occurrence probability calculator is further used to calculate a second occurrence probability of a temporary matching point corresponding to each first candidate position point of a current matching position point, each first candidate position point, and the second trajectory point, wherein the current matching position point is a matching position point on the map of a trajectory point that is located before the first trajectory point on the trajectory; and

The matching point determiner is further configured to select a first candidate position with a maximum second occurrence probability as a new current matching position point.

According to another embodiment of the present invention, there is provided an apparatus for matching trajectory points collected by a positioning system to a map, comprising:

a memory for storing executable instructions; and

The processor is configured to execute the executable instructions stored in the memory to perform the above method.

According to another embodiment of the present invention, there is provided a memory device carrying a computer program thereon, and when the computer program is executed by a processor, the computer program causes the processor to perform the above method.

The above solution can effectively increase the accuracy of map matching without significantly increasing the computational complexity by considering the matching probability of the next trajectory point of the required matching trajectory point.

BRIEF DESCRIPTION OF THE DRAWINGS

The above features and advantages of the present invention will become more apparent from the following detailed description of the invention in conjunction with the accompanying drawings, in which:

FIG1 is a schematic diagram showing a typical application scenario of the method and apparatus according to an embodiment of the present invention;

FIG2 shows a brief flowchart of a matching method according to an embodiment of the present invention;

FIG3 shows a simplified block diagram of a matching device according to an embodiment of the present invention;

FIG4 is a schematic diagram showing the principle of transition probability used in the method and apparatus according to an embodiment of the present invention; and

FIG5 is a simplified block diagram showing an exemplary hardware arrangement of the matching device shown in FIG3 according to an embodiment of the present invention.

DETAILED DESCRIPTION

Below, preferred embodiments of the present invention are described in detail with reference to the accompanying drawings. In the accompanying drawings, the same reference numerals are used to represent the same or similar components, although they are shown in different figures. For the sake of clarity and conciseness, detailed descriptions of known functions and structures contained herein will be omitted to avoid obscuring the subject matter of the present invention.

There are some special points in map matching technology, such as Y-shaped intersections. At these special points, it is easy to mistakenly match trajectory points to the wrong route using, for example, incremental matching technology. Figure 1 shows a schematic diagram of a specific application scenario of the method and apparatus according to an embodiment of the present invention. As shown in Figure 1, assuming that trajectory point _P1 has been successfully matched, its matching point is that there are two candidate position points for trajectory point _P2 and there are three candidate position points for trajectory point _P3 , and when using the existing incremental map matching technology, it is easy to cause the candidate position point to be selected as the map matching result of trajectory point _P2 because trajectory point _P2 is close to road _R3 . However, according to the overall trajectory of trajectory points _P1 , _P2 and _P3 , it is obvious that the candidate position point is the matching position point of trajectory point _P2 .

To accurately determine the matching position of a trajectory point (e.g., trajectory point P ₂ ) on a map, the present invention not only considers the trajectory point to be matched, but also considers the next point on the trajectory of the trajectory point (e.g., trajectory point P ₃ ). To this end, embodiments of the present invention provide the method and apparatus shown in Figures 2 and 3 .

FIG2 shows a method for matching track points collected by a positioning system to a map according to an embodiment of the present invention. The method includes:

Step S210, obtaining one or more first candidate location points of the first trajectory point on the map;

Step S220, obtaining one or more second candidate location points of a second trajectory point on the map, wherein the second trajectory point is a trajectory point after the first trajectory point on the trajectory;

Step S230, calculating a first occurrence probability of each first candidate location point and each second candidate location point;

Step S240: for each first candidate position point, selecting a second candidate position point having the greatest first occurrence probability therewith as a temporary matching point of the second trajectory point corresponding to each first candidate position point;

Step S250, calculating a second occurrence probability of a temporary matching point corresponding to each first candidate position point of the current matching position point, each first candidate position point, and the second trajectory point, wherein the current matching position point is a matching position point on the map of a trajectory point that is located before the first trajectory point on the trajectory; and

Step S260: Select the first candidate position with the largest second occurrence probability as the new current matching position point.

In some embodiments, the above-mentioned method for obtaining candidate location points may include: taking the first trajectory point as the center and a predetermined search distance as a radius, searching for the location point on each road on the map with the shortest straight-line distance to the first trajectory point, and using it as one or more first candidate location points for the first trajectory point on the map; and taking the second trajectory point as the center and a predetermined search distance as a radius, searching for the location point on each road on the map with the shortest straight-line distance to the second trajectory point, and using it as one or more second candidate location points for the second trajectory point on the map.

In some embodiments, the occurrence probability can be a function of the measurement probability and the transition probability. The measurement probability represents the probability of a candidate location point being a matching location point for its trajectory point, and the transition probability represents the probability of a candidate location point passing from the current trajectory point or the matching location point to the next trajectory point. However, it should be noted that while the function of the measurement probability and the transition probability is used as an example of the occurrence probability here, those skilled in the art may also use any parameter that can represent the likelihood of two or more location points coexisting.

In such an embodiment, calculating the first probability of occurrence may include:

Calculating a first measurement probability for each second candidate position point;

Calculating a first transition probability between each first candidate position point and each second candidate position point;

as well as

Each first transition probability is multiplied by the first measurement probability of the second candidate position point involved to obtain a corresponding first occurrence probability.

Calculating the second occurrence probability in this embodiment may include:

Calculating a second measurement probability for each first candidate position point;

Calculating a second transition probability from the current matching position point to each first candidate position point; and

For each first candidate position point, its corresponding second measurement probability, its corresponding second transition probability, and the first occurrence probability of the corresponding temporary matching point are multiplied to obtain the second occurrence probability corresponding to each first candidate position point of the current matching position point, each first candidate position point and the second trajectory point.

In some examples, the measurement probability may be expressed as:

Where, is the measurement probability of the candidate position point, _σp is the measurement standard deviation of the trajectory acquisition device, e is the base of the natural logarithm function, is the straight-line distance from the trajectory point _Pt to the candidate position point,

The standard deviation of the measurements of the trajectory acquisition device is

The transition probability is expressed as:

Among them, |P _t -P _t-1 | _{great circle} is the straight-line distance between the trajectory point P _t and its previous trajectory point P _t-1 , and is the path distance between the candidate position point of the trajectory point P _t and the candidate position point of its previous trajectory point P _t-1 .

FIG3 shows a device for matching track points collected by a positioning system to a map according to an embodiment of the present invention, which corresponds to the embodiment of FIG2 . As shown in FIG3 , the device includes:

a candidate location point acquirer 310, configured to acquire one or more first candidate location points of the first trajectory point on the map, and to acquire one or more second candidate location points of the second trajectory point on the map, wherein the second trajectory point is a trajectory point subsequent to the first trajectory point on the trajectory;

an occurrence probability calculator 320 for calculating a first occurrence probability of each first candidate location point and each second candidate location point; and

A matching point determiner 330 is configured to select, for each first candidate position point, a second candidate position point having a maximum first occurrence probability therewith as a temporary matching point of the second trajectory point corresponding to each first candidate position point;

The occurrence probability calculator 320 is further configured to calculate a second occurrence probability of a temporary matching point corresponding to each first candidate position point of a current matching position point, each first candidate position point, and the second trajectory point, wherein the current matching position point is a matching position point on the map of a trajectory point that precedes the first trajectory point on the trajectory; and

The matching point determiner 330 is further configured to select the first candidate position with the maximum second occurrence probability as a new current matching position point.

In some embodiments, the candidate location point acquirer 310 is also used to: search for the location point with the shortest straight-line distance to the first trajectory point on each road on the map with the first trajectory point as the center and a predetermined search distance as the radius, and use it as one or more first candidate location points for the first trajectory point on the map; and search for the location point with the shortest straight-line distance to the second trajectory point on each road on the map with the second trajectory point as the center and a predetermined search distance as the radius, and use it as one or more second candidate location points for the second trajectory point on the map.

In some embodiments, the occurrence probability can be a function of the measurement probability and the transition probability. The measurement probability represents the probability of a candidate location point being a matching location point for its trajectory point, and the transition probability represents the probability of a candidate location point passing from the current trajectory point or matching location point to the next trajectory point. Of course, as described above, those skilled in the art may also use any parameter that can represent the probability of two or more location points coexisting.

In the case where the occurrence probability may be a function of the measurement probability and the transition probability, the occurrence probability calculator 320 may also be used to:

Calculating a first measurement probability for each second candidate position point;

Calculating a first transition probability between each first candidate position point and each second candidate position point;

as well as

Each first transition probability is multiplied by the first measurement probability of the second candidate position point involved to obtain a corresponding first occurrence probability.

In addition, the occurrence probability calculator 320 may also be used to:

Calculating a second measurement probability for each first candidate position point;

Calculating a second transition probability from the current matching position point to each first candidate position point; and

For each first candidate position point, its corresponding second measurement probability, its corresponding second transition probability, and the first occurrence probability of the corresponding temporary matching point are multiplied to obtain the second occurrence probability of the temporary matching point from the current matching position point, each first candidate position point, and each first candidate position point.

In some examples, the measurement probability can be expressed as:

Where, is the measurement probability of the candidate position point, _σp is the measurement standard deviation of the trajectory acquisition device, e is the base of the natural logarithm function, is the straight-line distance from the trajectory point _Pt to the candidate position point,

The calculation method of the measurement standard deviation of the trajectory acquisition device is as follows:

The transition probability can be expressed as:

Among them, |P _t -P _t-1 | _{great circle} is the straight-line distance between the trajectory point P _t and its previous trajectory point P _t-1 , and is the path distance between the candidate position point of the trajectory point P _t and the candidate position point of its previous trajectory point P _t-1 .

In the above description of the embodiments shown in Figures 2 and 3, expressions such as "first" and "second" are used. However, it should be noted that such expressions are merely for the convenience of distinguishing different concepts of the same type, and unless explicitly stated, such expressions do not imply that "first" precedes "second" in time or space.

In some embodiments according to the present invention, the measurement probability can measure the distance between the candidate location point and the trajectory point, that is, the closer the candidate location point is to the trajectory point, the more likely it is to be the matching location point of the trajectory point. The candidate point can be searched by pre-setting a static or dynamic candidate point search radius, with the trajectory point as the center, and searching for roads based on the road network within this search radius. The searched candidate point is located on the road, and the straight-line distance between it and the trajectory point is the shortest. The distance between the trajectory point and the candidate location point and the measurement probability conform to the Gaussian distribution. For example, the following formula can be used to calculate the measurement probability:

Where σ _P is the standard deviation of the GNSS device's measurements, which can be obtained by evaluating the historical trajectory deviation of the GNSS device. In some embodiments of the present invention, the absolute median difference between the actual distance of the trajectory point and the road can be used to calculate:

As described above, as described above, where is the measurement probability of the candidate position point, _σp is the measurement standard deviation of the trajectory acquisition device, e is the base of the natural logarithm function, and is the straight-line distance from the trajectory point _Pt to the candidate position point.

The transition probability represents the probability of passing from the current trajectory point or matching location point to a candidate location point for the next trajectory point. In other words, it is assumed that when measuring traffic, the shortest path between two points always tends to be the one that complies with traffic regulations. The transition probability can be measured by comparing the shortest straight-line distance with the shortest path. The closer the two are, the higher the transition probability.

Figure 4 shows a schematic diagram of the principle of transition probability used in the method and apparatus according to an embodiment of the present invention. Based on the relationship shown in Figure 4, the following calculation formula for transition probability can be used:

As described above, | _Pt - _Pt-1 | _{great circle} is the straight-line distance between the trajectory point _Pt and its previous trajectory point Pt _-1 , and is the path distance between the candidate position point of the trajectory point _Pt and the candidate position point of its previous trajectory point Pt _-1 .

In the embodiment of the present invention, the measurement probability and the transition probability are comprehensively considered. The occurrence probability of each candidate position point can be equal to the product of the measurement probability and the transition probability of the candidate position point, that is:

The above formula only considers the use of one look-ahead point (i.e., the point on the trajectory that is after the point at which the matching position is to be determined). However, in other embodiments, more than one point can be used. The general calculation formula for the probability of occurrence in this case is as follows:

Here, n represents the number of look-ahead points, which can be selected based on the trade-off between computational complexity and matching accuracy.

For each candidate position point of the trajectory point to be matched, in addition to calculating the machine measurement probability and the transfer probability relative to the previous trajectory point, the matching probability (i.e., occurrence probability) of the candidate position point of the next trajectory point obtained based on each candidate position point of the current trajectory point is also calculated, and together they constitute the final matching probability of the current candidate position point. Finally, the candidate position point with the largest matching probability is selected from all candidate position points as the matching position point of the current trajectory point.

Taking the scenario shown in Figure 1 as an example, when calculating the map matching probability of the two candidate location points and of _P2 , we first calculate the measurement probabilities of the two candidate location points and the transition probabilities and calculated based on the matching location points of _P1. Then, we calculate the measurement probabilities and of the three candidate location points of _P3. Then, starting with and, we calculate the transition probabilities and of the three candidate location points of P3 and the transition probabilities and of the three candidate location points of _P3. The two sets of transition probabilities are multiplied by their corresponding measurement probabilities, and the maximum value of the two sets of results is taken as the temporary matching result of _P3 when assuming that and are the correct matching location points. Here, it is assumed that the maximum values correspond to and. Then, for the two candidate location points of _P2 , their final matching probabilities are calculated. As can be seen from the scenario shown in Figure 1, the higher the value, the candidate location point is finally selected as the final matching result of trajectory point _P2 , avoiding mistakenly selecting it as the matching location point of trajectory point _P2 .

Preferably, in the above embodiment of the present invention, the number of the look-ahead point is selected to be 1. However, it should be noted that more than one look-ahead point may also be selected.

FIG5 is a block diagram illustrating an example hardware arrangement 500 for the apparatus shown in FIG3 according to an embodiment of the present disclosure. The hardware arrangement includes a processor 506 (e.g., a microprocessor (μP), a digital signal processor (DSP), etc.). The processor 506 can be a single processing unit or a plurality of processing units for performing the different actions of the processes described herein. The arrangement can also include an input unit 502 for receiving signals from other entities and an output unit 504 for providing signals to other entities. The input unit 502 and the output unit 504 can be arranged as a single entity or as separate entities.

Furthermore, the arrangement may include at least one readable storage medium 508 in the form of a non-volatile or volatile memory, such as an electrically erasable programmable read-only memory (EEPROM), a flash memory, and/or a hard drive. The readable storage medium 508 includes a computer program 510 comprising code/computer-readable instructions that, when executed by the processor 506 in the arrangement 500, causes the hardware arrangement 500 and/or the device 100 including the hardware arrangement 500 to perform, for example, the process described above in conjunction with FIG. 2 and any variations thereof.

Computer program 510 can be configured as computer program code having, for example, an architecture of computer program modules 510A-510C. Thus, in an example embodiment, for example, when hardware arrangement 500 is used in device 100, the code in the computer program of arrangement 500 includes: module 510A for obtaining one or more first candidate locations on the map for a first trajectory point, and one or more second candidate locations on the map for a second trajectory point, wherein the second trajectory point is a trajectory point that follows the first trajectory point on the trajectory. The code in the computer program also includes: module 510B for calculating a first probability of occurrence for each first candidate location point and each second candidate location point. The code in the computer program also includes: module 510C for selecting, for each first candidate location point, the second candidate location point with the highest first probability of occurrence as a provisional matching point for each first candidate location point corresponding to the second trajectory point. Module 510B is further configured to calculate a second probability of occurrence for a current matching location point, each first candidate location point, and the provisional matching point for each first candidate location point corresponding to the second trajectory point, wherein the current matching location point is the matching location on the map for a trajectory point that precedes the first trajectory point on the trajectory. Module 510C may also be configured to select a first candidate location with the largest second occurrence probability as a new current matching location point.

The computer program modules can substantially execute the various actions in the process shown in Figure 2 to simulate the apparatus shown in Figure 3. In other words, when different computer program modules are executed in the processor 506, they can correspond to the above-mentioned different units in the apparatus shown in Figure 3.

Although the code means in the embodiment disclosed above in conjunction with Figure 5 are implemented as a computer program module, which, when executed in the processor 506, causes the hardware arrangement to perform the actions described above in conjunction with Figure 2, in an alternative embodiment, at least one of the code means may be at least partially implemented as a hardware circuit.

The processor may be a single CPU (central processing unit), but may also include two or more processing units. For example, the processor may include a general-purpose microprocessor, an instruction set processor and/or an associated chipset and/or a specialized microprocessor (e.g., an application-specific integrated circuit (ASIC)). The processor may also include onboard memory for cache purposes.

The computer program may be carried by a computer program product connected to the processor. The computer program product may include a computer-readable medium on which the computer program is stored. For example, the computer program product may be a flash memory, a random access memory (RAM), a read-only memory (ROM), or an EEPROM, and the above-mentioned computer program modules may be distributed to different computer program products in the form of memory within the UE in an alternative embodiment.

It should be noted that the technical solutions described in the embodiments of the present invention can be combined arbitrarily without conflict.

In the several embodiments provided by the present invention, it should be understood that the disclosed methods and devices can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as: multiple units or components can be combined, or can be integrated into another system, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the components shown or discussed can be through some interfaces, and the indirect coupling or communication connection of the devices or units can be electrical, mechanical or other forms.

The units described above as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units; some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, all functional units in the embodiments of the present invention can be integrated into a second processing unit, or each unit can be a separate unit, or two or more units can be integrated into one unit; the above-mentioned integrated units can be implemented in the form of hardware or in the form of hardware plus software functional units.

The above description is only used to implement the embodiments of the present invention. Those skilled in the art should understand that any modification or partial replacement without departing from the scope of the present invention should fall within the scope defined by the claims of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims (14)

1. A method for matching trajectory points collected by a positioning system to a map, comprising: Obtain one or more first candidate location points of the first trajectory point on the map; Obtain one or more second candidate location points on the map for the second trajectory point, wherein the second trajectory point is a trajectory point on the trajectory that follows the first trajectory point; Calculate the first occurrence probability of each first candidate location point and each second candidate location point; For each first candidate location point, a second candidate location point with the highest first occurrence probability is selected as a temporary matching point for the second trajectory point corresponding to each first candidate location point; Calculate the second probability of occurrence of the current matching location point, each first candidate location point, and the temporary matching point corresponding to each first candidate location point of the second trajectory point, wherein the current matching location point is the matching location point on the map of the trajectory point located before the first trajectory point; and Select the first candidate position with the highest probability of the second occurrence as the new current matching position. 2. The method according to claim 1, wherein the occurrence probability is a function of the measurement probability and the transition probability, the measurement probability represents the probability that a candidate location point is a matching location point of its trajectory point, and the transition probability represents the probability of passage from the current trajectory point or the matching location point to a candidate location point of the next trajectory point. 3. The method according to claim 2, wherein calculating the first probability of occurrence includes: Calculate the first measurement probability for each second candidate location point; Calculate the first transition probability of each first candidate location point and each second candidate location point; and Each first transition probability is multiplied by the first measurement probability of the second candidate location point involved to obtain the corresponding first occurrence probability. 4. The method according to claim 3, wherein calculating the second probability of occurrence includes: Calculate the second measurement probability for each first candidate location point; Calculate the second transition probability from the current matching position point to each first candidate position point; and For each first candidate location point, its corresponding second measurement probability, its corresponding second transition probability, and its corresponding first occurrence probability of a temporary matching point are multiplied together to obtain the current matching location point, the second occurrence probability of each first candidate location point, and the second trajectory point of the temporary matching point corresponding to each first candidate location point. 5. The method according to any one of claims 2 to 4, wherein, The measurement probability is expressed as: Where is the measurement probability of the candidate location point, σ_{_p} is the measurement standard deviation of the trajectory acquisition device, e is the base of the natural logarithm function, and is the straight-line distance from the trajectory point P _{_t} to the candidate location point. The method for calculating the standard deviation of measurements for trajectory acquisition equipment is as follows: The transition probability is expressed as: Where, |P _{_t} - _{P_t-1} | _{great circle} is the straight-line distance between trajectory point P _{_t} and its previous trajectory point P_t-1, and is the path distance between the candidate position point of trajectory point P _{_t} and the candidate position point of its previous trajectory point P _{_t-1} . 6. The method according to claim 1, wherein obtaining the first candidate location point comprises: taking the first trajectory point as the center and a predetermined search distance as the radius, searching for the location point on each road of the map with the shortest straight-line distance to the first trajectory point, and using it as one or more first candidate location points of the first trajectory point on the map, and Obtaining a second candidate location point includes: taking the second trajectory point as the center and a predetermined search distance as the radius, searching for the location point on each road on the map with the shortest straight-line distance to the second trajectory point, and using it as one or more second candidate location points of the second trajectory point on the map. 7. An apparatus for matching trajectory points collected by a positioning system to a map, comprising: A candidate location point acquirer is used to acquire one or more first candidate location points of a first trajectory point on the map, and to acquire one or more second candidate location points of a second trajectory point on the map, wherein the second trajectory point is a trajectory point on the trajectory that follows the first trajectory point; An occurrence probability calculator is used to calculate the first occurrence probability of each first candidate location point and each second candidate location point; and A matching point determiner is used to select, for each first candidate location point, a second candidate location point with the highest first probability of occurrence as a temporary matching point of the second trajectory point corresponding to each first candidate location point; The probability calculator is further used to calculate the second probability of occurrence of the temporary matching point corresponding to each first candidate location point and the second trajectory point, wherein the current matching location point is the matching location point on the map of the trajectory point located before the first trajectory point; and The matching point determiner is further used to select the first candidate position with the highest second occurrence probability as the new current matching position point. 8. The apparatus of claim 7, wherein the occurrence probability is a function of the measurement probability and the transition probability, the measurement probability representing the probability that a candidate location point is a matching location point of its trajectory point, and the transition probability representing the probability of passage from the current trajectory point or the matching location point to a candidate location point of the next trajectory point. 9. The apparatus of claim 8, wherein the probability calculator is further configured to: Calculate the first measurement probability for each second candidate location point; Calculate the first transition probability of each first candidate location point and each second candidate location point; and Each first transition probability is multiplied by the first measurement probability of the second candidate location point involved to obtain the corresponding first occurrence probability. 10. The apparatus of claim 9, wherein the probability calculator is further configured to: Calculate the second measurement probability for each first candidate location point; Calculate the second transition probability from the current matching position point to each first candidate position point; and For each first candidate location point, its corresponding second measurement probability, its corresponding second transition probability, and its corresponding first occurrence probability for the temporary matching point are multiplied together to obtain the second occurrence probability of the current matching location point, each first candidate location point, and the temporary matching point of each first candidate location point. 11. The apparatus according to any one of claims 8 to 10, wherein, The measurement probability is expressed as: Where is the measurement probability of the candidate location point, σ_{_p} is the measurement standard deviation of the trajectory acquisition device, e is the base of the natural logarithm function, and is the straight-line distance from the trajectory point P _{_t} to the candidate location point. The method for calculating the standard deviation of measurements for trajectory acquisition equipment is as follows: The transition probability is expressed as: Where, |P _{_t} - _{P_t-1} | _{great circle} is the straight-line distance between trajectory point P _{_t} and its previous trajectory point P_t-1, and is the path distance between the candidate position point of trajectory point P _{_t} and the candidate position point of its previous trajectory point P _{_t-1} . 12. The apparatus of claim 7, wherein the candidate location point acquirer is configured to: Using the first trajectory point as the center and a predetermined search distance as the radius, search for the point on the map with the shortest straight-line distance to the first trajectory point on each road, and use this point as one or more first candidate location points of the first trajectory point on the map. Using the second trajectory point as the center and a predetermined search distance as the radius, search for the location point on each road on the map that has the shortest straight-line distance to the second trajectory point, and use it as one or more second candidate location points of the second trajectory point on the map. 13. An apparatus for matching trajectory points collected by a positioning system to a map, comprising: Memory, used to store executable instructions; and A processor for executing executable instructions stored in memory to perform the method according to any one of claims 1 to 6. 14. A memory device thereon carrying a computer program, which, when executed by a processor, causes the processor to perform the method according to any one of claims 1 to 6.