Method and device for evaluating spatio-temporal continuity of GPS data, and storage medium

Abstract

The embodiment of the present disclosure provides a GPS data space-time continuity evaluation method, device and storage medium, which comprises the following steps: collecting GPS data; calculating the time continuity feature of the GPS data, wherein the time continuity feature of the GPS data comprises the delay distribution and the loss rate of the GPS data; calculating the space continuity feature of the GPS data, wherein the space continuity feature of the GPS data comprises the spatial distance and the heading angle change rate of adjacent GPS points; respectively judging the continuity of the GPS data in time and space according to the time continuity feature of the GPS data and the space continuity feature of the GPS data; when the GPS data is continuous in time and space, it is determined that the GPS data is continuous in space-time; if either or both of the GPS data in time and space are discontinuous, it is determined that the GPS data is discontinuous in space-time. The continuity evaluation index adopted by the present disclosure is more specific and detailed, the data features are more abundant, and the actual situation under the movement and shielding is more practical.

Description

TECHNICAL FIELD

[0001] The present disclosure belongs to the technical field of GPS data stability evaluation, and particularly relates to a GPS data space-time continuity evaluation method, device and storage medium. BACKGROUND

[0002] In the field of intelligent transportation and vehicle-road cooperative system, positioning data of vehicles cannot be dispensed with. Vehicle positioning based on GPS is a low-cost way to obtain vehicle positioning. The stability of GPS data is the key to the safe, effective and stable operation of the whole vehicle-road cooperative or intelligent transportation system. The stability of GPS data determines the scope and depth of its use. Poor stability can only be used for statistical analysis of information systems and management with low accuracy requirements. High stability and accuracy can be applied to the field of assisted driving or autonomous driving. With the evaluation method of GPS data space-time continuity, it is possible to determine whether the GPS positioning data has failed and whether it needs to be maintained or replaced. The existing evaluation of GPS data quality is generally carried out in the laboratory under limited scenarios for corresponding data analysis, and cannot cover all scenarios in actual situations. SUMMARY

[0003] The present disclosure aims to at least solve one of the technical problems existing in the prior art.

[0004] To this end, the GPS data space-time continuity evaluation method provided by the first aspect of the present disclosure has strong practicability and is more suitable for evaluation of mobile positioning GPS signals. The evaluation method comprises the following steps:

[0005] collecting GPS data;

[0006] calculating GPS time continuity features, wherein the GPS data time continuity features include GPS data delay distribution and loss rate;

[0007] calculating GPS data space continuity features, wherein the GPS data space continuity features include spatial distance and heading angle change rate of adjacent GPS points;

[0008] determining the continuity of the GPS data in time and space according to the GPS data time continuity features and the GPS data space continuity features, respectively. When the GPS data is continuous in time and space, it is determined that the GPS data is continuous in space-time. If either or both of the GPS data in time and space are discontinuous, it is determined that the GPS data is discontinuous in space-time.

[0009] The GPS data space-time continuity evaluation method provided by the first aspect of the present disclosure has the following characteristics and advantages:

[0010] The GPS data space-time continuity evaluation method provided by the first aspect of the embodiment of the present disclosure is based on the delay distribution and loss rate of GPS data, and the spatial distance and heading angle change rate of adjacent GPS points as the evaluation index of GPS data space-time continuity. The method is more specific, detailed, and rich in data features, and has strong practicability. It is not only suitable for static object GPS signal evaluation, but also more suitable for mobile positioning GPS signal evaluation.

[0011] In some embodiments, the collected GPS data includes: collection time, data sequence number, GPS accuracy, GPS latitude, GPS heading angle, GPS vehicle speed, and GPS signal strength.

[0012] In some embodiments, the delay distribution of the GPS data is to count the proportion of GPS data in different delay times. The proportion of GPS data within X seconds of delay is set as the amount of GPS data within X seconds of delay / the total amount of GPS data, and the data delay time is GPS data receiving time-GPS data collection time.

[0013] In some embodiments, the loss rate of the GPS data is GPS lost data number / total amount of GPS data, and the GPS lost data number is sum(received data current record sequence number-(received data last record sequence number-1)).

[0014] In some embodiments, the spatial distance of the adjacent GPS points is calculated according to the spatial distance of two consecutive GPS data, and the calculation formula is as follows:

[0015]

[0016] Wherein, L 1,2 is the spatial distance of two adjacent GPS points P1=(x1, y1) and P2=(x2, y2), x1 and x2 are the longitude of the two GPS points, and y1 and y2 are the latitude of the two GPS points.

[0017] In some embodiments, the heading angle change rate of the adjacent GPS points is calculated according to the following steps:

[0018] Suppose the heading angles of two adjacent GPS points are a and b, and a<b, the heading angle change rate is the heading angle change amount / time interval of the two adjacent GPS points, wherein if b-a>180°, the heading angle change amount is a+360°-b; otherwise, the heading angle change amount is b-a.

[0019] In some embodiments, for time continuity judgment, if any one or more of the following conditions is met, it is determined that the GPS data is continuous in time, and if none of the following conditions is met, it is determined that the GPS data is not continuous in time:

[0020] (t1) the proportion of GPS data delayed for a certain period of time exceeds a first threshold value, and (t2) the loss rate of GPS data does not exceed a second threshold value;

[0021] For spatial continuity judgment, if any one or more of the following conditions is met, it is determined that the GPS data is spatially continuous, and if none of the following conditions is met, it is determined that the GPS data is not spatially continuous:

[0022] (s1) the proportion of data whose spatial distance from the adjacent GPS point exceeds a first set value does not exceed a third threshold value, (s2) the proportion of data whose spatial distance from the adjacent GPS point exceeds a second set value does not exceed a fourth threshold value, and (s3) the proportion of data whose change rate of heading angle exceeds a third set value does not exceed a fifth threshold value.

[0023] In some embodiments, for the scenario of only longitudinal vehicle speed control, the determination conditions are set as follows:

[0024] (t1) the proportion of GPS data delayed for 1 second exceeds 90%, and the proportion of GPS data delayed for 3 seconds exceeds 99%;

[0025] (t2) the loss rate of GPS data is less than 0.8%;

[0026] (s1) under the premise that the collection frequency of GPS data is 10 Hz, the proportion of data whose spatial distance from the adjacent GPS point exceeds a first set value does not exceed 0.5%;

[0027] (s2) under the premise that the collection frequency of GPS data is 10 Hz, the proportion of data whose spatial distance from the adjacent GPS point exceeds a second set value does not exceed 0.5%, and the second set value is a value related to vehicle speed;

[0028] (s3) under the premise that the collection frequency of GPS data is 10 Hz, the proportion of data whose change rate of heading angle exceeds a third set value does not exceed 0.5%.

[0029] The GPS data space-time continuity evaluation device provided by the second aspect of the present disclosure comprises:

[0030] a GPS data collection module for collecting GPS data;

[0031] a first calculation module for calculating the time continuity feature of the GPS data, wherein the time continuity feature of the GPS data includes the delay distribution and the loss rate of the GPS data;

[0032] a second calculation module configured to calculate spatial continuity features of the GPS data, the spatial continuity features of the GPS data including spatial distances of adjacent GPS points and a change rate of a heading angle;

[0033] an evaluation module configured to determine continuity of the GPS data in time and in space respectively according to the temporal continuity features and the spatial continuity features of the GPS data, and determine that the GPS data is continuous in time and in space when the GPS data is continuous in time and in space, and determine that the GPS data is not continuous in time and in space when the GPS data is not continuous in time and in space in either or both of time and space.

[0034] The computer readable storage medium provided by the third aspect of the present disclosure stores computer instructions, and the computer instructions are used to make the computer execute the GPS data space-time continuity evaluation method provided by the first aspect of the present disclosure. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 a flowchart of the GPS data space-time continuity evaluation method provided by the first aspect of the present disclosure;

[0036] Figure 2 an architecture diagram of a data acquisition platform used in the GPS data space-time continuity evaluation method provided by the first aspect of the present disclosure.

[0037] Figure 3 a structural schematic diagram of the GPS data space-time continuity evaluation device provided by the second aspect of the present disclosure.

[0038] Figure 4 a structural schematic diagram of the electronic device provided by the third aspect of the present disclosure. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical scheme and advantages of the present application clearer, the present application is further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not to limit the present application.

[0040] On the contrary, the present application covers any alternative, modification, equivalent method and scheme made on the essence and scope of the present application as defined by the claims. Further, in order to make the public better understand the present application, some specific details are described in detail in the following detailed description of the present application. The present application can also be completely understood without the description of these details by those skilled in the art.

[0041] REFERENCE Figure 1 The GPS data space-time continuity evaluation method provided by the first aspect of the present disclosure includes the following steps:

[0042] collecting GPS data;

[0043] calculating time continuity features of the GPS data, the time continuity features of the GPS data including a delay distribution and a loss rate of the GPS data;

[0044] calculating spatial continuity features of the GPS data, the spatial continuity features of the GPS data including a spatial distance of adjacent GPS points and a change rate of a heading angle;

[0045] judging continuity of the GPS data in time and in space respectively according to the time continuity features and the spatial continuity features of the GPS data, when the GPS data is continuous in time and in space, it is judged that the GPS data is continuous in time and in space, and if the GPS data is discontinuous in time and in space, it is judged that the GPS data is discontinuous in time and in space.

[0046] In some embodiments, the GPS data is collected by using a data collection platform as shown in Figure 2 Specifically, a data collection module, a GPS setting device and a communication device are installed on a target vehicle, wherein the data collection module can adopt a vehicle-mounted T-BOX (Telematics BOX) or an OBU (On board Unit), the data collection module transmits the GPS data collected by the positioning device to the cloud through the communication device and a 4G / 5G network, the data receiving time and the GPS data are stored in a database after being processed by a data receiving module of the cloud, or the data receiving time and the GPS data are transmitted to a cloud message queue through a message bus.

[0047] In some embodiments, the collected GPS data includes: collection time, data serial number, GPS accuracy, GPS latitude, GPS heading angle, GPS vehicle speed, wheel speed, GPS signal strength and other GPS key data, the T-Box or OBU intelligent device uploads the GPS data to the cloud data receiving module through the 4G or 5G network, the data receiving module records the receiving time of each GPS data, and the receiving time and the data uploaded by the vehicle end are stored in the database or the message queue of the cloud for subsequent evaluation, and the GPS sample data is shown in Table 1.

[0048] Table 1 GPS data sample

[0049]

[0050]

[0051] In some embodiments, most of the intelligent connected vehicles currently still use 4G communication or 5G public network, and the stability and delay are poor. Therefore, the time continuity state monitoring of collected data is particularly important. The present disclosure mainly monitors the time continuity of GPS data as follows: 1) time delay statistics, 2) data loss statistics, that is, the delay distribution and loss rate of GPS data are taken as the spatial continuity features of GPS data, which are described as follows:

[0052] 1) Time delay statistics

[0053] The premise of time delay statistics is to use network time protocol (NTP) to synchronize the time of vehicle terminal device and cloud platform, achieve clock synchronization, and use the difference between cloud GPS data receiving time and vehicle GPS data sending time as delay time. The delay indicators mainly include data proportion within 1 second delay, data proportion within 2 seconds delay, and data proportion within X seconds delay, wherein:

[0054] Data delay time = cloud GPS data receiving time - vehicle GPS data collection time

[0055] Data proportion within X seconds delay = GPS data amount within X seconds delay / total GPS data amount

[0056] The GPS data delay example of intelligent connected vehicle is shown in Table 2.

[0057] Table 2 GPS data delay example of intelligent connected vehicle

[0058]

[0059]

[0060] 2) Data loss statistics

[0061] The implementation of data loss statistics is to continuously sequence the data sent by the vehicle terminal, and the data receiving module of the cloud end statistics the loss of the sequence number.

[0062] GPS lost data number = sum (cloud end received data current record sequence number - cloud end received data last record sequence number - 1)

[0063] GPS data loss rate = GPS lost data number / total GPS data amount, of course, the lost data can be supplemented by using the retransmission mechanism.

[0064] The GPS data loss rate example of intelligent connected vehicle is shown in Table 3.

[0065] Table 3 GPS data loss rate example of intelligent connected vehicle

[0066] License plate number GPS loss data GPS total data amount GPS data loss rate D09026D 10800 548758 0.019 D08375D 1405 84731 0.016 D08101D 3473 221247 0.015 D06807D 228 15649 0.014 D07122D 6062 449375 0.013 D06003D 6529 519123 0.012 D05976D 6233 535104 0.012 D07273D 5152 475190 0.011 D03916D 6091 588912 0.010 D09870D 1460 530053 0.003 D07126D 1199 443421 0.003 D08719D 789 294824 0.003 D01319D 1223 470175 0.003

[0067] The GPS data space-time continuity evaluation method provided by the embodiments of the present disclosure takes the time delay distribution and loss rate of GPS data as the parameters for evaluating time continuity, and has the advantages of clearer delay characteristics, better actual application effect, etc. compared with the commonly used time discontinuity indexes such as average delay time and maximum delay time.

[0068] In some embodiments, according to the collected GPS data, the GPS space continuity features are constructed and calculated, including:

[0069] 1) Distance continuity feature

[0070] The GPS data space continuity mainly considers whether the spatial distance of adjacent GPS points meets the continuity, wherein:

[0071] The spatial distance of adjacent GPS points = calculate the spatial distance of two consecutive GPS data

[0072] Specifically, assuming that P1 = (x1, y1) and P2 = (x2, y2) are two GPS points, x1 and x2 are the longitude of the two GPS points respectively, and y1 and y2 are the latitude of the two GPS points respectively, then the spatial distance of the two GPS points is calculated according to the following formula:

[0073]

[0074] wherein, L 1,2 is the spatial distance of adjacent two GPS points P1 = (x1, y1) and P2 = (x2, y2), and the unit is kilometer, x1 and x2 are the longitude of the two GPS points respectively, and y1 and y2 are the latitude of the two GPS points respectively; 6378.138 is the radius of the earth, and the unit is kilometer

[0075] The proportion of data whose distance exceeds Y meters = the amount of data whose distance exceeds Y meters / the total amount of GPS data, for example, in the case of 10Hz collection frequency and 60km / h maximum vehicle speed, Y can be 10;

[0076] 2) Calculate the heading angle change rate of adjacent GPS points

[0077] The heading angle change is calculated, assuming that the heading angles of two GPS points are a and b respectively, and a < b, the heading angle change rate = heading angle change amount / time interval, wherein if b-a > 180°, then the heading angle change amount = a + 360°-b; otherwise, the heading angle change amount = b-a.

[0078] The GPS data space-time continuity evaluation method provided by the embodiments of the present disclosure uses distance continuity and heading angle change rate as the GPS space continuity features, and compared with the commonly used space discontinuity indexes such as average offset distance and maximum offset distance of GPS in a static state, the method is more applicable to a scene with a higher data collection frequency (>=1Hz) and occlusion.

[0079] In some embodiments, the GPS data space-time continuity judgment mainly includes time and space continuity judgment, wherein:

[0080] For time continuity judgment, if any one or more of the following conditions is met, it is determined that the GPS data is continuous in time, and if none of the following conditions is met, it is determined that the GPS data is not continuous in time:

[0081] (t1) the delay ratio of the GPS data within a certain period of time exceeds a first threshold, and (t2) the loss rate of the GPS data does not exceed a second threshold;

[0082] For space continuity judgment, if any one or more of the following conditions is met, it is determined that the GPS data is continuous in space, and if none of the following conditions is met, it is determined that the GPS data is not continuous in space:

[0083] (s1) the data ratio of the spatial distance between two adjacent GPS points exceeding a first set value does not exceed a third threshold, (s2) the data ratio of the spatial distance between two adjacent GPS points exceeding a second set value does not exceed a fourth threshold, and (s3) the data ratio of the change rate of the heading angle of two consecutive GPS data exceeding a third set value does not exceed a fifth threshold.

[0084] Specifically, for a scene of only longitudinal vehicle speed control, each condition can be designed as follows:

[0085] (t1) the delay ratio of the GPS data within 1 second exceeds 90%, and the delay ratio of the GPS data within 3 seconds exceeds 99%;

[0086] (t2) the loss rate of the GPS data is less than 0.8%;

[0087] (s1) under the premise that the GPS data collection frequency is 10Hz, the data ratio of the spatial distance between two adjacent GPS points exceeding a first set value does not exceed 0.5%;

[0088] (s2) under the premise that the collection frequency of the GPS data is 10 Hz, the proportion of data in which the spatial distance between two adjacent GPS points exceeds a second set value is not more than 0.5%, and the second set value is a value related to the vehicle speed, and optionally, the second set value is vehicle speed * time interval * coefficient, wherein the vehicle speed is set as the vehicle speed measured by the GPS in the case where the wheel speed is not collected, the time interval is the inverse of the GPS data collection frequency, and the coefficient can be set according to the data distribution of GPS distance / (vehicle speed * time interval), for example, the value when the proportion reaches 95% can be selected as the coefficient;

[0089] (s3) under the premise that the collection frequency of the GPS data is 10 Hz, the proportion of data in which the change rate of the GPS heading angle of two consecutive GPS data exceeds a third set value is not more than 0.5%.

[0090] For other application scenarios, such as lateral speed control of a vehicle, each threshold value can be set according to the corresponding data distribution.

[0091] Further, in order to make the GPS spatiotemporal continuity evaluation more practical, the GPS spatiotemporal continuity can be monitored and warned in time segments, such as hours and days. Therefore, on the basis of the foregoing GPS spatiotemporal continuity evaluation, GPS spatiotemporal continuity warning can also be performed, mainly considering the warning index, the triggering condition, the warning period and frequency, which are described as follows:

[0092] (1) Determination of the warning index

[0093] The same data, specifically, the continuity feature of the GPS data of a certain period of the day is compared with the continuity feature of the same GPS data of the same period of the same day of the previous week;

[0094] The ring data, specifically, the continuity feature of the GPS data of a certain period of the day is compared with the continuity feature of the same GPS data of the same period of the previous day;

[0095] The hourly increase, specifically, the continuity feature of the GPS data of a certain period of the day is compared with the continuity feature of the same GPS data of the previous period.

[0096] (2) Determination of the triggering condition

[0097] The triggering condition of the data warning is set according to the normal floating range of the warning index, and when the warning index is lower than or higher than the normal floating range, the warning is triggered.

[0098] (3) Determination of the warning period and frequency

[0099] The early warning is generally periodic early warning, usually once a day, once an hour, 0.5 hours, and the real-time requirement of the intelligent networked vehicle starting the advanced auxiliary driving function will be higher, and there are 1 second and 100 ms.

[0100] The GPS data space-time continuity evaluation device provided by the second aspect of the present disclosure is shown in Figure 3 , comprising:

[0101] The GPS data acquisition module is configured to acquire GPS data.

[0102] The first calculation module is configured to calculate the time continuity feature of the GPS data, wherein the time continuity feature of the GPS data includes the delay distribution and the loss rate of the GPS data.

[0103] The second calculation module is configured to calculate the space continuity feature of the GPS data, wherein the space continuity feature of the GPS data includes the spatial distance and the heading angle change rate of adjacent GPS points.

[0104] The evaluation module is configured to determine the continuity of the GPS data in time and space according to the time continuity feature and the space continuity feature of the GPS data, and when the GPS data is continuous in time and space, it is determined that the GPS data is continuous in space-time, and if the GPS data is not continuous in time and space, it is determined that the GPS data is not continuous in space-time.

[0105] In order to realize the above-mentioned embodiments, the present disclosure further provides a computer readable storage medium having a computer program stored thereon, wherein the program is executed by a processor to execute the GPS data space-time continuity evaluation method of the above-mentioned embodiments.

[0106] Reference is made to Figure 4 , which shows a structural schematic diagram of an electronic device 100 suitable for implementing the embodiments of the present disclosure. It should be noted that the electronic device 100 in the embodiments of the present disclosure can include but is not limited to mobile terminals such as mobile phones, notebook computers, digital broadcast receivers, PDAs (personal digital assistants), PADs (tablets), PMPs (portable multimedia players), vehicle terminals (such as vehicle navigation terminals) and the like, and fixed terminals such as digital TVs, desktop computers, servers and the like. Figure 4 The electronic device shown is only an example, and should not limit the functions and use range of the embodiments of the present disclosure.

[0107] As Figure 4As shown, the electronic device 100 can include a processing device (e.g., a central processing unit, a graphics processing unit, etc.) 101 that can perform various appropriate actions and processes according to programs stored in a read-only memory (ROM) 102 or loaded into a random access memory (RAM) 103 from a storage device 108. Various programs and data required for the operation of the electronic device 100 are also stored in the RAM 103. The processing device 101, the ROM 102, and the RAM 103 are connected to each other through a bus 104. An input / output (I / O) interface 105 is also connected to the bus 104.

[0108] Generally, the following devices can be connected to the I / O interface 105: input devices 106 including, for example, a touch screen, a touch pad, a keyboard, a mouse, a camera, a microphone, etc.; output devices 107 including, for example, a liquid crystal display (LCD), a speaker, a vibrator, etc.; storage devices 108 including, for example, a magnetic tape, a hard disk, etc.; and communication devices 109. The communication devices 109 can allow the electronic device 100 to communicate with other devices wirelessly or wired to exchange data. Although Figure 4 The electronic device 100 is shown with various devices, but it is understood that all of the shown devices are not required to be implemented or present. More or fewer devices can alternatively be implemented or present.

[0109] In particular, according to embodiments of the present disclosure, the processes described above with reference to the flowcharts can be implemented as a computer software program. For example, the present embodiments include a computer program product comprising a computer program carried on a computer readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network through the communication devices 109, or installed from the storage devices 108, or installed from the ROM 102. When the computer program is executed by the processing device 101, the above-mentioned functions defined in the methods of the embodiments of the present disclosure are performed.

[0110] It should be noted that the computer readable medium in the present disclosure can be a computer readable signal medium or a computer readable storage medium or any combination of the two. The computer readable storage medium may, for example, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or apparatus, or any combination of the above. More specific examples of the computer readable storage medium can include, but are not limited to, an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In the present disclosure, the computer readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, device or apparatus. In the present disclosure, the computer readable signal medium can include a data signal carried in a baseband or as a part of a carrier wave, which carries computer readable program code. Such a propagated data signal can take various forms, including but not limited to an electromagnetic signal, an optical signal or any suitable combination of the above. The computer readable signal medium can also be any computer readable medium other than the computer readable storage medium, which can send, propagate or transmit a program for use by or in conjunction with an instruction execution system, device or apparatus. The program code contained in the computer readable medium can be transmitted by any suitable medium, including but not limited to a wire, an optical cable, an RF (radio frequency) or the like, or any suitable combination of the above.

[0111] The computer readable medium described above can be contained in the electronic device described above; or can exist separately and not be assembled into the electronic device.

[0112] The computer readable medium described above carries one or more programs, when the one or more programs are executed by the electronic device, the electronic device is caused to: collect GPS data; calculate the time continuity feature of the GPS data, the time continuity feature of the GPS data including the delay distribution and the loss rate of the GPS data; calculate the spatial continuity feature of the GPS data, the spatial continuity feature of the GPS data including the spatial distance of adjacent GPS points and the change rate of the heading angle; determine the continuity of the GPS data in time and space respectively according to the time continuity feature and the spatial continuity feature of the GPS data, when the GPS data is continuous in time and space, it is determined that the GPS data is continuous in time and space, if the GPS data is not continuous in time and space, it is determined that the GPS data is not continuous in time and space.

[0113] Computer program code for carrying out operations of the present disclosure can be written in any combination of one or more programming languages, including an object oriented programming language such as Java, Smalltalk, C++, Python, or the like, and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code can execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection can be made to an external computer (for example, through the Internet using an Internet Service Provider).

[0114] In the description of the specification, the description of the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Also, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, the person skilled in the art can combine and combine the different embodiments or examples described in the specification and the features of the different embodiments or examples, without contradiction.

[0115] In addition, the terms "first", "second", etc. are used only for the purpose of description and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, for example, two, three, etc., unless otherwise specifically limited.

[0116] Any process or method descriptions or descriptions of the flow diagrams in the specification or elsewhere in this document, can be understood as representing the steps of the code of the modules, segments or portions of the code for implementing specific logic functions or steps in the process, and the scope of the preferred embodiments of the present application includes additional implementation in which the steps are performed in different order, including an essentially simultaneous performance of the functions according to the involved functions, or in reverse order, which should be understood by those skilled in the art of the embodiments of the present application.

[0117] The logic and / or steps represented in the flowcharts and / or described herein, for example, can be considered as a sequence of instructions to implement logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, apparatus, or device, such as a computer-based system, processor- based system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions. For purposes of this specification, a "computer-readable medium" can be any apparatus that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. The computer-readable medium can be a computer- readable storage medium or a computer-readable signal medium. The computer-readable storage medium can be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of the computer-readable storage medium include the following: an electrical connection having one or more wires (electrical connections), a portable computer diskette (a magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, and a portable compact disc read-only memory (CDROM). In addition, the computer-readable medium can even be paper or another suitable medium upon which the program is printed, as the program can be electronically captured, for example, via optical scanning of the paper or other medium, then compiled, interpreted, or otherwise processed in a suitable manner, if necessary, and stored in a computer memory.

[0118] It should be understood that aspects of the application can be implemented in hardware, software, firmware or combinations thereof. In the above embodiments, the various steps or methods can be implemented in software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented in hardware, and in another embodiment, any of the following technologies, known in the art, or their combinations can be used: discrete logic circuitry having logic gates for implementing logic functions on data signals, application specific integrated circuits having appropriate combinational logic gates, programmable gate arrays (PGA), field programmable gate arrays (FPGA), and the like.

[0119] Those skilled in the art can understand that all or part of the steps carried out by the above-mentioned embodiments can be completed by programs instructing related hardware, and the developed programs can be stored in a computer-readable storage medium, and the programs include one or a combination of steps of the method embodiments when executed.

[0120] In addition, each of the functional units in the various embodiments of the present application can be integrated in one processing module, or each of the units can be physically present separately, or two or more units can be integrated in one module. The integrated module can be realized in the form of hardware or in the form of a software functional module. When the integrated module is realized in the form of a software functional module and sold or used as an independent product, it can also be stored in a computer readable storage medium.

[0121] The storage medium mentioned above can be a read-only memory, a magnetic disk or an optical disk, etc. Although the embodiments of the present application have been shown and described above, it should be understood that the above embodiments are exemplary and should not be construed as limiting the present application, and those skilled in the art can make changes, modifications, replacements and variations to the above embodiments within the scope of the present application.

Claims

1. A method for evaluating the spatio-temporal continuity of GPS data, characterized in that, The method comprises: collecting GPS data; calculating a time continuity feature of the GPS data, the time continuity feature of the GPS data comprising a delay distribution of the GPS data and a loss rate of the GPS data; calculating a space continuity feature of the GPS data, the space continuity feature of the GPS data comprising a spatial distance of adjacent GPS points and a change rate of a heading angle; judging continuity of the GPS data in time, space and time-space respectively according to the time continuity feature of the GPS data and the space continuity feature of the GPS data, when the GPS data is continuous in time and space, it is judged that the GPS data is continuous in time-space, if either or both of the GPS data is not continuous in time and space, it is judged that the GPS data is not continuous in time-space; for the time continuity judgment, if any one or more of the following conditions is met, it is judged that the GPS data is continuous in time, if none of the following conditions is met, it is judged that the GPS data is not continuous in time: (t1) the delay proportion of the GPS data within a certain period of time exceeds a first threshold value, (t2) the loss rate of the GPS data does not exceed a second threshold value; for the space continuity judgment, if any one or more of the following conditions is met, it is judged that the GPS data is continuous in space, if none of the following conditions is met, it is judged that the GPS data is not continuous in space: (s1) the proportion of data whose spatial distance exceeds a first set value does not exceed a third threshold value, (s2) the proportion of data whose spatial distance exceeds a second set value does not exceed a fourth threshold value, (s3) the proportion of data whose change rate of heading angle exceeds a third set value does not exceed a fifth threshold value.

2. The method of claim 1, wherein, The collected GPS data comprises: collection time, data serial number, GPS accuracy, GPS latitude, GPS heading angle, GPS vehicle speed and GPS signal strength.

3. The method of claim 1, wherein, The delay distribution of the GPS data is to count the proportion of GPS data within different delay times, and the proportion of GPS data with a delay of X seconds or less is equal to the amount of GPS data with a delay of X seconds or less divided by the total amount of GPS data, and the data delay time is equal to the GPS data receiving time minus the GPS data collection time.

4. The method of claim 1, wherein, The loss rate of the GPS data is equal to the number of lost GPS data divided by the total amount of GPS data, and the number of lost GPS data is equal to sum(received data current record serial number - (received data last record serial number - 1)).

5. The method of claim 1, wherein, The spatial distance of adjacent GPS points is calculated according to the spatial distance of two consecutive GPS data, and the calculation formula is as follows: wherein L 1,2 is the spatial distance between two adjacent GPS points P1 = (x1, y1) and P2 = (x2, y2), x1, x2 are the longitude of the two GPS points, and y1, y2 are the latitude of the two GPS points.

6. The method of claim 1, wherein, The change rate of the heading angle of the adjacent GPS points is calculated according to the following steps: Let the heading angles of the adjacent two GPS points be a and b respectively, and a < b, the change rate of the heading angle is equal to the change amount of the heading angle divided by the time interval of the adjacent two GPS points, wherein, if b-a > 180°, the change amount of the heading angle is equal to a+360°-b; otherwise, the change amount of the heading angle is equal to b-a.

7. The method of claim 1, wherein, For the scenario of only controlling the longitudinal vehicle speed of the vehicle, the determination conditions are set as follows: (t1) the delay proportion of the GPS data within 1 second exceeds 90%, and the delay proportion of the GPS data within 3 seconds exceeds 99%. (t2) the loss rate of the GPS data is less than 0.8%; (s1) under the condition that the acquisition frequency of the GPS data is 10 Hz, the proportion of data whose spatial distance between adjacent GPS points exceeds a first set value is not more than 0.5%; (s2) under the condition that the acquisition frequency of the GPS data is 10 Hz, the proportion of data whose spatial distance between adjacent GPS points exceeds a second set value is not more than 0.5%, the second set value being a value related to the vehicle speed; (s3) under the condition that the acquisition frequency of the GPS data is 10 Hz, the proportion of data whose change rate of heading angle between adjacent GPS points exceeds a third set value is not more than 0.5%.

8. A GPS data space-time continuity evaluation device, characterized by, comprise: a GPS data acquisition module, configured to acquire GPS data; a first calculation module, configured to calculate the time continuity feature of the GPS data, the time continuity feature of the GPS data comprising the delay distribution and the loss rate of the GPS data; a second calculation module, configured to calculate the spatial continuity feature of the GPS data, the spatial continuity feature of the GPS data comprising the spatial distance between adjacent GPS points and the change rate of heading angle; an evaluation module, configured to determine the continuity of the GPS data in time and in space respectively according to the time continuity feature and the spatial continuity feature of the GPS data, when the GPS data is continuous in time and in space, it is determined that the GPS data is continuous in time and in space, if the GPS data is discontinuous in time and in space, it is determined that the GPS data is discontinuous in time and in space; for the time continuity determination, if any one or more of the following conditions is met, it is determined that the GPS data is continuous in time, if none of the following conditions is met, it is determined that the GPS data is discontinuous in time: (t1) the proportion of GPS data whose delay exceeds a first threshold value in a certain period of time, (t2) the loss rate of the GPS data is not more than a second threshold value; for the spatial continuity determination, if any one or more of the following conditions is met, it is determined that the GPS data is continuous in space, if none of the following conditions is met, it is determined that the GPS data is discontinuous in space: (s1) the proportion of data whose spatial distance between adjacent GPS points exceeds a first set value is not more than a third threshold value, (s2) the proportion of data whose spatial distance between adjacent GPS points exceeds a second set value is not more than a fourth threshold value, (s3) the proportion of data whose change rate of heading angle between two consecutive GPS data exceeds a third set value is not more than a fifth threshold value.

9. A computer-readable storage medium, characterized in that, The computer readable storage medium stores computer instructions for causing the computer to execute the GPS data space-time continuity evaluation method of any one of claims 1-7. The computer readable storage medium stores computer instructions for causing the computer to execute the GPS data space-time continuity evaluation method of any one of claims 1-7.

Images