KR20130052497A - Apparatus and method of determining relative distance and position using global positioning system information - Google Patents

Abstract

PURPOSE: A device for determining relative distances and locations by using GPS(Global Positioning System) information and a method thereof are provided to acquire relative distances between multiple terminals individually equipped with a GPS receiver and locations of the terminals, to improve the efficiency and accuracy of positioning by performing satellite information exchange through ad hoc communications, and to enable effective management of dangerous situations around, which can affect the operation of a mobile object itself. CONSTITUTION: Each terminal receives GPS information by using a GPS receiver(210). A first terminal exchanges GPS information with a second terminal by using wireless communications(220). The first terminal compares its own GPS information with the GPS information of the second terminal, and selects a common GPS satellite where the GPS information coincides with each other(230). Absolute coordinates of the first terminal and second terminal are produced by using the selected common satellite(240). Relative distances between the two terminals and locations of the terminals are produced by using the produced absolute coordinates of the first terminal and second terminal(250). [Reference numerals] (210) Terminals receive GPS information from a GPS satellite by using a GPS receiver included in the terminals; (220) First terminal exchanges GPS information with a second terminal by using wireless communication; (230) First terminal compares its own GPS information and the GPS information received from the second terminal and selects a common GPS satellite; (240) Calculate absolute coordinates of the first terminal and second terminal by using the selected common GPS satellite; (250) Operate the difference of the calculated absolute coordinates of the first terminal and second terminal and calculate a location and a relative distance between the two terminals; (AA) Start; (BB) End

Description

Apparatus and method of determining relative distance and position using global positioning system information}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for determining relative distances and positions between a plurality of objects, and in particular, between a global positioning system (GPS) information received from a satellite in a mobile body such as a car and other objects present around the mobile body. An apparatus, a method for determining the relative distance between objects and the position of each moving object using communication, and a recording medium recording the same.

Global Positioning System (GPS) is a satellite navigation system that receives signals from GPS satellites and calculates the user's current position. It is mainly used in navigation devices such as aircraft, ships, and cars, and recently, it is being widely used in smartphones and tablet PCs.

GPS consists of the satellite, ground control and user sectors. The satellite sector refers to GPS satellites, the ground control section refers to control stations located on the ground, and the user section refers to GPS receivers.

There are about 30 GPS satellites on Earth. Of these, 24 satellites are distributed across six orbits struggling with the Earth, allowing at least six GPS satellites to be observed anywhere in the world. The remaining six satellites act as backups if 24 satellites fail. GPS satellites are powered by solar energy and last about 8 to 10 years. The control station is divided into a main control station in Colorado Springs, USA, and five sub-control stations distributed around the world. Each secondary control station tracks the GPS satellites passing over it, measures the distance and rate of change, and sends them to the primary control station. The main control station collects the information and processes the satellite to maintain orbit. The GPS receiver consists of an antenna for receiving signals from GPS satellites, a clock, software for processing signals, and an output device for outputting the signals.

By adopting such a GPS to a moving body such as a vehicle, the non-patent literature cited below is related to not only information about the movement of the vehicle but also technologies and patents that can be applied to various fields such as control and driving of the vehicle. It was suggested through.

However, the conventional method using the GPS receiver is used only to grasp its position or driving situation by using only the GPS information received through one GPS receiver. There is no support, and this does not provide information on the relative position of various objects surrounding the moving object.

 Patent Trend of Automotive GPS (Global Positioning System), Yoo Mi, Korea Institute of Patent Information, 2002.

The technical problem to be solved by the present invention is that the mobile receiving the GPS information can only grasp its own position, and only the GPS information received from the GPS satellites can be used to determine the relative positional relationship with other objects such as a moving object or a fixed object around the moving object. Overcoming the limitations that can not be grasped, and thereby to solve the problem that can not effectively cope with the danger of the surrounding environment that can act on the movement of the moving body itself.

In order to solve the above technical problem, a method of determining a relative distance between a plurality of terminals according to an embodiment of the present invention, the terminal using a global positioning system (GPS) receiver provided in each of the plurality of terminals Receiving GPS information from each GPS satellite; Exchanging, by the first terminal, the received own GPS information with a second terminal using wireless communication; Selecting, by the first terminal, common GPS satellites that are identical by comparing the GPS information received from the second terminal with GPS information received from the second terminal; Calculating absolute coordinates of the first terminal and the second terminal by using the selected common GPS satellite; And calculating a difference between the calculated absolute coordinates of the first terminal and the calculated absolute coordinates of the second terminal to calculate a relative distance and a position between them.

In the method of determining the relative distance between the plurality of terminals according to an embodiment, the GPS information received from the GPS satellites is GPS raw data, such as code waves, phase waves, messages and NMEA protocols. Contains data.

In the method of determining the relative distance between the plurality of terminals according to an embodiment, the wireless communication is communication based on an Ad-hoc network between the terminals.

In the method of determining the relative distance between the plurality of terminals according to an embodiment, the selected common GPS satellites are at least three or more, and the absolute coordinates of the terminals is a radius of the distance between the terminal and the GPS satellites It is calculated from the intersection of at least three circles.

In the method of determining the relative distance between the plurality of terminals according to an embodiment, the terminal is installed in the moving body, further comprising the step of estimating the position of the moving body using a Kalman filter (Kalman filter).

According to an embodiment, there is provided a method of determining a relative distance between a plurality of terminals, wherein the first terminal is repeatedly performing the processes with respect to a plurality of terminals existing around the terminal, and thus the relative distance and position with each of the terminals. Determining; And forming a topology around the first terminal itself from the relative distances and positions determined for the plurality of terminals.

Furthermore, the following provides a computer readable recording medium having recorded thereon a program for executing a method for determining a relative distance between a plurality of terminals described above in a computer.

In order to solve the above technical problem, an apparatus for determining a relative distance between a plurality of terminals according to an embodiment of the present invention, the GPS receiver provided in the terminal for receiving GPS information from a GPS satellite; A wireless communication unit receiving GPS information of the peripheral terminal from the peripheral terminal; And comparing the GPS information of the terminal with the GPS information received from the neighboring terminal, selecting a common GPS satellite that is identical to each other, and using the selected common GPS satellite, absolute coordinates of the terminal itself and the neighboring terminal. And calculating a relative distance and a position between the two by calculating the respective differences between the calculated absolute coordinates.

In an apparatus for determining a relative distance between the plurality of terminals according to an embodiment, the GPS information received from the GPS satellites is GPS raw data and includes code waves, phase waves, messages, and NMEA protocol data.

In an apparatus for determining a relative distance between the plurality of terminals according to an embodiment, the wireless communication is communication based on an ad hoc network between the terminals.

In an apparatus for determining a relative distance between the plurality of terminals according to an embodiment, the selected common GPS satellites are at least three or more, and the absolute coordinates of the terminals is a radius of the distance between the terminal and the GPS satellites It is calculated from the intersection of at least three circles.

In an apparatus for determining a relative distance between the plurality of terminals according to an embodiment, the terminal is installed in a mobile body, an inertial sensor (inertial sensor) for detecting the inertial force according to the movement of the mobile body or the pressure applied to the mobile body The apparatus further includes an air pressure sensor configured to detect an error, and the calculation unit corrects an error of the GPS information by using the inertial sensor or the air pressure sensor.

In the apparatus for determining the relative distance between the plurality of terminals according to an embodiment, the operation unit, the relative distance and the position for each of the plurality of terminals in the periphery of the terminal, determine the relative distance And a topology around the terminal itself from the location.

Embodiments of the present invention by selecting the common GPS satellites of the GPS information received through the plurality of receivers, and calculates the absolute coordinates and relative coordinates of each receiver therefrom, thereby the relative distance between the terminal having a plurality of receivers and It is possible to obtain a location, improve the efficiency and accuracy of positioning by performing satellite information exchange using ad-hoc communication, and effectively cope with the surrounding danger situation that may affect the movement of the mobile body itself.

1 is a view for explaining the basic idea of calculating the relative distance between a plurality of moving objects that embodiments of the present invention adopts.
2 is a flowchart illustrating a method of determining a relative distance between a plurality of terminals according to an embodiment of the present invention.
3 is a diagram illustrating a process of selecting a common GPS satellite in two GPS receivers by using a device for determining a relative distance between a plurality of terminals according to an embodiment of the present invention.
4 is a diagram illustrating a sequential data processing process of two terminals in FIG. 3 according to an embodiment of the present invention.
5 is a block diagram illustrating an apparatus for determining a relative distance between a plurality of terminals according to an embodiment of the present invention.

Prior to describing the embodiments of the present invention, the problem recognition of the present invention related to the technical field related to the positioning in the moving object in which the embodiments of the present invention are utilized, and the basic idea to solve the problem will be introduced.

As a positioning method using satellites, there are known Global Positioning System (GPS), Differential Global Positioning System (DGPS), and Assisted Global Positioning System (AGPS). The method of reducing the position error by receiving the information for error correction measured at the base station / reference station in general GPS raw data (DGPS) and the AGPS (AGPS). In general, the GPS positioning system determines its position through self-calculation based on the positioning information of the satellites in the case of general GPS, and analyzes the satellite information at the base station or the reference station in the case of DPS and AGPS. It is a method to reduce the positioning error by applying satellite error information of a certain area (base station / reference station communication distance, satellite error coverage) to general GPS.

However, according to the above-described conventional positioning method, the relative position / distance of a vehicle, a terminal, a roadside device, etc. which exist around the moving body cannot be accurately determined only by the GPS information received by the moving body itself. In particular, the conventional satellite positioning system cannot reduce the degree of error without analyzing satellite information at the base station / reference station and applying error information of a predetermined region (base station / reference station communication distance, satellite error coverage).

For example, a moving vehicle can only know its current location through the GPS information it receives, but cannot know the location of surrounding vehicles. Although additional conditions such as an ultrasonic transmitting and receiving device or a camera may be used to determine the surroundings, in situations such as a shield between the moving vehicles or at night, the additional devices may accurately display information about the surrounding moving vehicles. It is very difficult to secure.

Accordingly, the present invention has been made to solve this problem, and provides a technical means that can measure and grasp the relative distance to the object around the moving object using GPS information.

Typically, GPS calculates the distance between the GPS satellites and the GPS receiver to obtain coordinates. If we can pinpoint the location and distance of the GPS satellites, we can get the exact location with only three GPS satellites. This is because we live on the earth's surface, which is roughly a three-dimensional sphere. If it is one-dimensional, such as a straight line, it is easy to determine the location by knowing two reference points and their respective distance values. In a two-dimensional world, you need to know three reference points and their distance values. This is because the point where the three circles meet when the reference point is the center of the circle and the distance value is the radius is the corresponding position. Similarly, in three dimensions, you can find the location where four spheres overlap. However, since the earth's surface itself acts as a sphere, three GPS satellites can, in principle, determine its position.

 However, this alone does not actually calculate distance correctly. The distance between the GPS satellites and the GPS receiver is calculated based on the arrival time of the radio waves sent by the satellite, because an error occurs because the clock mounted on the satellite and the clock mounted on the receiver do not coincide. Therefore, it is necessary to receive radio waves from four or more GPS satellites to determine the exact location. Recently emerging GPS receivers can receive signals from 20 satellites and calculate their position accurately.

Accordingly, embodiments of the present invention analyze GPS raw data to obtain satellite information, and share the analysis contents (including phase information) through ad-hoc wireless communication to select concurrency / synchrony. To calculate the absolute coordinates of not only the mobile body with GPS receivers but also various objects (including mobile and stationary bodies) with nearby GPS receivers, and based on the results, It provides a technical means capable of calculating the relative distance between a mobile body or a mobile body (self) -fixing body.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description and the accompanying drawings, detailed description of well-known functions or constructions that may obscure the subject matter of the present invention will be omitted. In addition, it should be noted that like elements are denoted by the same reference numerals as much as possible throughout the drawings.

FIG. 1 is a view for explaining a basic idea of calculating a relative distance between a plurality of moving objects that embodiments of the present invention employ. As a moving object, two vehicles R1 and R2 are illustrated. Suppose each is equipped with a GPS receiver.

In FIG. 1, the mobile vehicle R1 and the mobile vehicle R2 selectively receive GPS information from 10 GPS satellites, respectively. R1 analyzes the received GPS raw data to recognize that it has received GPS information from 2, 4, 5, 6, 7, 9, and 10 satellites. R2 may also analyze the received GPS raw data to recognize that it has received GPS information from 1, 3, 4, 5, 6, 7, 8 satellites. Now, the mobile vehicles R1 and R2 share their respective analyzed GPS raw data information via communication means. Such a communication means is not limited to a specific communication standard, and various data communication means, which are easy to exchange GPS information, may be utilized. However, such a communication means will be generally a short-range wireless communication means, considering the environment in which the technology according to the present embodiment is utilized, in particular, without the need for a separate repeater or communication control server terminals (all communication provided in the mobile vehicle) Module). Preferably, the communication is based on an Ad-hoc network for mutual communication.

At this time, according to Figure 1 it can be seen that the mobile vehicles R1 and R2 in common received GPS information from satellites 4, 5, 6, 7. In order to calculate the relative position between R1 and R2, embodiments of the present invention calculate positions based on common satellites, that is, satellite information 4, 5, 6 and 7. This is because the absolute coordinates determined based on the satellites commonly selected by both are used as basic data for calculating relative distances and positions between the moving bodies. Thus, in embodiments of the present invention, the GPS information utilized in calculating absolute coordinates must be GPS raw data received from a common satellite. That is, in order to calculate the relative distance in FIG. 1, the first receiver (mobile vehicle R1) and the second receiver (mobile vehicle R2) calculate the relative distance using the same GPS satellite, respectively.

More specific implementation process is as follows.

(1) Mobile vehicles R1 and R2 each receive GPS information from the satellite.

(2) R1 receives the GPS satellite information received by the neighboring terminal itself from the neighboring terminal including the GPS receiver using wireless communication (for example, may utilize ad hoc wireless communication). In the case of FIG. 1, R2 transmits or broadcasts GPS information received by R2 to R1. Of course, R2 may also receive GPS information received by R1 from R1 as needed. That is, the terminals may exchange their GPS information with terminals located nearby. By doing so, one terminal can acquire not only GPS raw data directly received from GPS satellites, but also GPS raw data of terminals located nearby.

(3) The receiving side R1 compares the received neighbor receiver R2 with the GPS satellite information collected through its GPS receiver and selects a matching (same) GPS satellite. That is, the GPS satellites are selected so that the source of the GPS reception is the same. For example, in the case of Figure 1 will be 4, 5, 6, 7 satellites.

(4) In order to calculate the relative distance between moving vehicles, the absolute position must first be calculated. To calculate the absolute position, various positioning methods using GPS satellites can be used. As briefly introduced above, in general, since GPS information must be received from at least three satellites in order to calculate an absolute position, it is desirable that the number of matching (same) GPS satellites is also at least three. If the number of GPS satellites with a matching (same) source is less than the minimum number of satellites required for positioning (for example, it can be three), then each GPS satellite is randomly selected by the number of satellites that are insufficient. Positioning values calculated from the selected GPS satellites may be set to keep the weight relatively low. Now, the absolute coordinates of the self R1 and the counterpart R2 are calculated using the GPS information received from the at least three satellites thus selected. That is, the moving vehicle R1 may acquire both its own absolute coordinates and the absolute coordinates of R2. Likewise, if necessary, the moving vehicle R2 may also obtain the absolute coordinates of R1 and R2, respectively, in the same manner.

(5) Then, by calculating the difference value of the calculated absolute coordinates, it is possible to determine the relative distance and position between both R1 and R2.

Using the above idea, a mobile body can accurately grasp not only its own position but also its relative positional relationship with various objects (of course, it should have a GPS receiver) located near the mobile body itself.

FIG. 2 is a flowchart illustrating a method of determining a relative distance between a plurality of terminals according to an embodiment of the present invention. In the position of the mobile body R1 (hereinafter, referred to as a first terminal) of FIG. Steps for determining relative distance and location with terminals are described.

In step 210, the terminals each receive GPS information from a GPS satellite using a global positioning system (GPS) receiver provided in the plurality of terminals. In this case, the GPS information received from the GPS satellites may include code waves, phase waves, messages, and NMEA protocol data as GPS raw data.

In step 220, the first terminal exchanges its GPS information received in step 210 with the second terminal using wireless communication. Of course, if necessary, the first terminal may receive only the GPS information of the second terminal without providing its own GPS information to the second terminal. At this time, the wireless communication, it is preferable that the communication based on the ad-hoc (Ad-hoc) network between the terminals to configure a direct communication network between the two for the efficiency of the communication.

In operation 230, the first terminal compares its GPS information with the GPS information received from the second terminal and selects a common GPS satellite to which the two terminals match. That is, select a GPS satellite with the same source. In this case, the selected common GPS satellites are at least three or more, and the absolute coordinates of the terminals may be calculated from the intersection of at least three circles having a radius of the distance between the terminal and the GPS satellites. If the number of common GPS satellites is three or less, an arbitrary number of GPS satellites may be selected, but it is desirable to maintain positioning accuracy by giving a relatively low weight to the randomly selected satellites.

In operation 240, the first terminal calculates absolute coordinates of the first terminal and the second terminal, respectively, using the common GPS satellite selected in operation 230.

In operation 250, the first terminal calculates a difference between the absolute coordinates of the first terminal and the absolute coordinates of the second terminal calculated in operation 240, and calculates a relative distance and a position therebetween.

Meanwhile, the above process (the process of calculating the mutual distance and the position between the first terminal and the second terminal by the first terminal) may be repeatedly performed not only for the second terminal but also for a plurality of terminals existing around the first terminal. There will be. Through this process, the first terminal can determine the relative distance and the location of the surrounding terminals, respectively. Now, the first terminal can form a topology around the first terminal itself from the relative distances and positions determined for the plurality of terminals. Such a topology can help to determine what movements each of the moving objects has about their own, like coordinates displayed on a map, and can provide various services related to automobile safety by using them. For example, the vehicle may be used for collision avoidance services between vehicles, lane recognition services on complex roads, and information providing services regarding the possibility of passing.

3 is a diagram illustrating a process of selecting a common GPS satellite in two GPS receivers by using a device for determining a relative distance between a plurality of terminals according to an embodiment of the present invention. Although some configurations are implemented somewhat differently from the method implemented in the actual vehicle, the essence is the same as the process of FIGS. 1 and 2 introduced above.

3 shows two GPS receivers A and B representing a moving object, and for convenience, the received information is transferred to a specific calculator (PC or various processors may be utilized) through an interface such as USB. These calculators are interconnected to collect GPS raw data received via GPS receivers A and B as shown at 220.

Now, in step 230, it is illustrated that the GPS satellites commonly used for positioning can be selected by collecting the GPS raw information included in the GPS information analyzed by each calculator and comparing them. That is, GPS raw data received through each GPS receiver is compared to select a GPS satellite having the same source.

According to the embodiments of the present invention described above, by selecting a common GPS satellite among the GPS information received through a plurality of receivers, and calculates the absolute coordinates and relative coordinates of each receiver therefrom, having a plurality of receivers The relative distance between the terminals (which can be mobile) can be obtained.

In particular, the accuracy of the conventional positioning system using GPS is limited, and the conventional method of improving the accuracy by receiving error correction information from the base station / reference station to improve the positioning accuracy is found to be limited in infrastructure construction and coverage. On the other hand, according to the relative distance measuring technology adopted by the embodiments of the present invention, it is possible to improve the efficiency of positioning through the exchange of satellite information by using the ad hoc communication, and the accuracy of the positioning is also DGPS or Age PS. It shows the positioning error of (Improved to (AGPS)) (for example, the experiment shown in the example of Figure 3, the error within 0.3m) improved than (AGPS).

4 is a diagram illustrating a sequential data processing process of two terminals in FIG. 3 according to an embodiment of the present invention. FIG. 4 is a diagram illustrating data processed in a terminal including GPS receivers A and B and data exchanged with each other. To illustrate. Each process is performed sequentially and corresponds to the processes described in FIG.

In step 210, the GPS receivers A and B each receive a set of GPS information containing GPS raw data from a GPS satellite. In FIG. 4, this information set is illustrated as 'AGPSInfSet' and 'BGPSInfSet', respectively.

In step 220, GPS receivers A and B (or may be terminals with it) exchange their GPS information sets.

In step 230, each terminal having GPS receivers A and B selects / extracts the same set of GPS information by comparing its GPS information with the GPS information received from the counterpart terminal.

In step 240, each of the terminals with GPS receivers A and B calculates absolute coordinates for the GPS receivers A and B from the selected common set of GPS information, and again calculates the relative distance and position between them from their differences. 4 illustrates these relative distances as 'DAB1' and 'DAB2', respectively. In principle, these relative distances are ideally determined to be the same value.

In operation 450, the position of the terminal may be selectively estimated using a Kalman filter. At this time, the terminal is provided in the mobile body, which is based on the assumption that the mobile body moves based on a dynamic system having linearity over time. The Kalman filter is used to predict key variables (e.g., the location of the moving object / plane or the tracking object, etc.) that are essential during the operation of each system in the position control or navigation of the moving object / plane. It is also widely used to minimize errors that can occur in linear systems.

For example, if the GPS information acquisition period is one second, the interval is wide enough to be applied to a high-speed moving object, and the Kalman filter is used to predict or estimate the information between GPS acquisition periods to smooth the effect. You can get it. Predicting information between cycles of GPS location data collection using the Kalman filter is to predict the next location information based on the previous location information and the current location information. Information can be generated and utilized. The smoothing effect refers to mitigating when a sudden change in relative distance occurs due to an error, and the effect is obtained by substituting the predicted next position information into the actually measured position information.

In the present embodiment, the position measurement value of the moving object may include a probabilistic error. If the state at a specific time point of the moving object has a linear relationship with the state of the previous time point in time, the Kalman values are continuously measured. Position estimation is possible using a filter. That is, continuous information can be calculated based on the relative distance and position between the moving objects determined through the present embodiments, and correction of the error included therein is possible.

In general, Kalman filter assumes the linearity of the model, but the model for many moving objects in the natural world often follows the nonlinear structure. Thus, rather than applying the Kalman filter directly or simply applying an approximated model, we can relax this linearity assumption to take advantage of techniques such as the Extended Kalman filter (EKF). Since the specific technique regarding the application and modification of the Kalman filter may impair the essence of the present invention, only the outline has been described above. One of ordinary skill in the art to which the present invention pertains can fully understand that various technical means for correcting the probabilistic error included in the measured value and estimating the change in the position of the moving object may be utilized by utilizing the above principle. have.

FIG. 5 is a block diagram illustrating an apparatus for determining a relative distance between a plurality of terminals according to an embodiment of the present invention, wherein each of the components corresponds to a process introduced in the relative distance determining method of FIG. 2. Do this. Therefore, while focusing on introducing the configuration in terms of device here, the description of the overlapping operation will be outlined. In FIG. 5, only two terminals 10 and 20 are shown for convenience, and it is assumed that both have the same structure in essential components (GPS receiver, wireless communication unit, and computing unit).

The GPS receivers 11 and 21 are provided in the terminals 10 and 20 to receive GPS information from the GPS satellites. At this time, the GPS information received from the GPS satellites, as GPS raw data, preferably includes code waves, phase waves, messages, and NMEA protocol data.

The wireless communication units 12 and 22 receive GPS information of the peripheral terminal from the peripheral terminal. In this case, the wireless communication is preferably an ad hoc network based communication between the terminals in order to improve the efficiency of communication and network control.

The calculating unit 13, 23 compares the GPS information of the terminal 10 and 20 with the GPS information received from the neighboring terminal, selects a common GPS satellite that is identical to each other, and uses the selected common GPS satellite. By calculating the absolute coordinates of the terminal itself and the peripheral terminal, respectively, by calculating the difference between the calculated absolute coordinates, the relative distance and position between them are calculated. Of course, as described above, the selected common GPS satellites are at least three or more, and the absolute coordinates of the terminals may be calculated from intersections of at least three circles having a radius of the distance between the terminal and the GPS satellites.

In addition, the operation unit 13, 23 determines the relative distance and position for each of the plurality of terminals existing around the terminal 10, 20, and determines the terminal itself from the determined relative distance and position. A topology can be formed around the center.

The computing units 13 and 23 receive a series of electronic data from the GPS receivers 11 and 21 and the wireless communication units 12 and 22 to perform a defined operation and extract useful information from the processed data. do. Accordingly, the operation unit may be implemented in the form of a combination of various types of processors capable of performing these operations and memory capable of storing temporary data and program codes required for the operations.

Meanwhile, the terminals 10 and 20 may further include an inertial sensor that is installed in the moving body and detects an inertial force according to the movement of the moving body or an air pressure sensor that detects the air pressure applied to the moving body. In this case, the calculation units 13 and 23 can be utilized to correct the error of the GPS information by using the sensors 14 and 24. In addition to the GPS information, the inertial sensor or barometric pressure sensor can be used in addition to detect the change in the characteristics of the inertial driving of the moving object in real time, and can also detect the movement of the moving object even when the GPS information is temporarily not received. It can be used as the main means to detect.

The sensors 14 and 24 may be used according to the current position and direction in consideration of the acceleration and the current speed of the vehicle, and thus may be used for periodic position prediction. In addition, by substituting the measured value into the position information predicted by the Kalman filter to obtain complementary correction information, the previous position can be obtained even in a region where GPS is not received (for example, a shaded region such as a tunnel). It can be used to predict the relative distance through the information and measurement information such as the speed of the vehicle itself and the relative vehicle, acceleration or direction. Furthermore, other sensors, such as barometric pressure sensors, may be used for calculating distances and positions in consideration of these variables by predicting changes in signals that change according to environmental factors applied to each moving object.

These sensors 14 and 24 may be selectively used as needed, and those skilled in the art may have an air pressure / inertia in the relative distance and position measuring method adopted by the embodiments of the present invention. It can be seen that various methods of correcting the error of the accelerometer using the sensor can be applied.

According to the embodiments of the present invention described above, by selecting a common GPS satellite among the GPS information received through the plurality of receivers and calculating absolute and relative coordinates of each receiver therefrom, It can acquire the relative distance and location between the terminals, improve the efficiency and accuracy of positioning by performing satellite information exchange using ad hoc communication, and can effectively cope with the surrounding danger situation that can affect the movement of the mobile body itself. have.

Furthermore, embodiments of the present invention can be implemented in computer readable codes on a computer readable recording medium. A computer-readable recording medium includes all kinds of recording apparatuses in which data that can be read by a computer system is stored.

Examples of the computer-readable recording medium include a ROM, a RAM, a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device and the like, and also a carrier wave (for example, transmission via the Internet) . In addition, the computer-readable recording medium may be distributed over network-connected computer systems so that computer readable codes can be stored and executed in a distributed manner. In addition, functional programs, codes, and code segments for implementing the present invention can be easily deduced by programmers skilled in the art to which the present invention belongs.

The present invention has been described above with reference to various embodiments. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. Therefore, the disclosed embodiments should be considered in an illustrative rather than a restrictive sense. The scope of the present invention is defined by the appended claims rather than by the foregoing description, and all differences within the scope of equivalents thereof should be construed as being included in the present invention.

10: first terminal 20: second terminal
11, 21: GPS receiver 12, 22: wireless communication unit
13, 23: calculator 14, 24: sensor

Claims (12)

In the method of determining the relative distance between a plurality of terminals,
Receiving GPS information from GPS satellites by using global positioning system (GPS) receivers respectively provided in the plurality of terminals;
Exchanging, by the first terminal, the received own GPS information with a second terminal using wireless communication;
Selecting, by the first terminal, common GPS satellites that are identical by comparing the GPS information received from the second terminal with GPS information received from the second terminal;
Calculating absolute coordinates of the first terminal and the second terminal by using the selected common GPS satellite; And
And calculating a difference between the calculated absolute coordinates of the first terminal and the calculated absolute coordinates of the second terminal to calculate a relative distance and a position between them. The method of claim 1,
GPS information received from the GPS satellites,
GPS raw data, comprising: code wave, phase wave, message, and NMEA protocol data. The method of claim 1,
The wireless communication is characterized in that the communication based on the ad-hoc (Ad-hoc) network between the terminals. The method of claim 1,
The selected common GPS satellite is at least three,
Absolute coordinates of said terminals are calculated from the intersection of at least three circles with a radius of the distance between said terminal and said GPS satellites. The method of claim 1,
The terminal is installed in a mobile body,
Estimating the position of the moving object using a Kalman filter,
And wherein the moving body moves based on a dynamic system having linearity over time. The method of claim 1,
Determining a relative distance and a location of each of the terminals by repeatedly performing the processes on a plurality of terminals existing around the first terminal; And
And forming a topology around the first terminal itself from the relative distances and positions determined for the plurality of terminals. In the device for determining the relative distance between a plurality of terminals,
A GPS receiver provided in the terminal to receive GPS information from a GPS satellite;
A wireless communication unit receiving GPS information of the peripheral terminal from the peripheral terminal; And
Comparing the GPS information of the terminal and the GPS information received from the peripheral terminal to select a common GPS satellite that both match, and using the selected common GPS satellite to determine the absolute coordinates of the terminal itself and the peripheral terminal And calculating units calculating the relative distances and positions between the two by calculating the difference between the calculated absolute coordinates. The method of claim 7, wherein
GPS information received from the GPS satellites,
GPS raw data, comprising: code waves, phase waves, messages and NMEA protocol data. The method of claim 7, wherein
And wherein the wireless communication is communication based on an ad hoc network between the terminals. The method of claim 7, wherein
The selected common GPS satellite is at least three,
And the absolute coordinates of the terminals are calculated from the intersection of at least three circles with the radius of the distance between the terminal and the GPS satellites. The method of claim 7, wherein
The terminal is installed in a mobile body,
And an inertial sensor for detecting an inertial force according to the movement of the movable body or an atmospheric pressure sensor for detecting an air pressure applied to the movable body.
Wherein the calculation unit corrects the error of the GPS information using the inertial sensor or the atmospheric pressure sensor. The method of claim 7, wherein
The calculation unit,
Determine the relative distance and location for each of a plurality of terminals present in the periphery of the terminal,
And forming a topology around the terminal itself from the determined relative distance and location.

Images