KR20010064089A - Land position-tracking method - Google Patents

Abstract

PURPOSE: A position tracking method is provided to be able to track easily by taking a wireless transmitter with software to transmit position signal. CONSTITUTION: A position tracking system is composed of a wireless transmitter(10), a base station(20a, 20b, 20c), a position tracking center(30). The wireless transmitter(10) has a transmission unit to transmit a radio with ID signal and position signal for tracking position at a random position in area of being able to receive the radio. The wireless transmitter(10) has a band of VHF/UHF. The position signal has a structure defined to analyze start point and finish point of signal received in some of base station. The position signal is transmitted continuously for a fixed time. The base station(20a, 20b, 20c) analyzes the signal from the wireless transmitter(10), and detects a position signal from specific wireless transmitter, and measures the reception time of the position signal, and calculates delay time of radio from transmission to reception. Each of base station(20a, 20b, 20c) receives only position signal and specific ID of the wireless transmitter(10) with the specific delay conditions.

Description

Ground position tracking method {LAND POSITION-TRACKING METHOD}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a location tracking technology, and more particularly, to a terrestrial location tracking method that actively or passively tracks a location of a radio transmitter using a delay time measured by a plurality of base stations receiving a location signal of the radio transmitter. will be.

Conventional location tracking systems have been proposed in various ways. These include: location tracking system using GPS satellites, progressive source location tracking system using high-directional antennas, beacon location tracking system that detects the location of vehicles passing through the road by installing many transceivers on the road, PCS or Local tracking method that analyzes the radio wave received at base station such as cellular phone to determine the approximate location, and transmits the signal for calculating the synchronized position at regular intervals from base station of mobile phone and receives the received signal at portable receiver Location tracking method that calculates its own location using the signal delay and the information of the base station.

Since the methods used in the location tracking system are methods for tracking the location of the person carrying the receiver, there are inadequate problems as a countermeasure when an emergency situation occurs.

GPS signal reception method, which is used most frequently, cannot track location in obstacle areas such as indoors, tunnels, dense buildings, and forests, and requires a lot of power at all times for fast location tracking. There are disadvantages.

In addition, if the GPS receiver does not respond in case of emergency, the utilization is very poor. The gradual position tracking method using the high directional antenna has a receiver equipped with the high directional antenna to keep track of the direction and intensity of radio waves. In this manner, there is a disadvantage that the tracking time is very long and the system is expensive.

The location tracking system using beacons requires a large amount of transmission and reception devices at regular intervals on the road. Therefore, the location tracking system requires a lot of cost, and it is difficult to track the location in the off-road area. The method of calculating the delay time can reduce the obstacles of location tracking, but there are problems that the price of the mobile phone increases considerably, and the additional system installation cost is very high for the non-mobile phone. .

The present invention has been made to solve the above problems, and according to the purpose of use, the radio transmitter device is equipped with a method (active positioning operation method) to actively notify their location and the radio transmitter or radio transmitter It is to provide a ground position tracking method to remotely maneuver a moving object to perform a position tracking method (passive position tracking operation method) in a situation that the mobile phone does not know.

The present invention for achieving the above object is a wireless transmission device for transmitting a location signal of a specific type for location tracking, a plurality of base stations receiving the location signal, and the plurality of base stations in communication with the location of the wireless transmission device A location tracking method in a system consisting of a location tracking center for tracking coordinates, the method comprising: (a) driving the radio transmitter according to a purpose of location tracking to transmit the location signal and a unique number of the radio transmitter; (b) generating and transmitting, at the plurality of base stations, delay information data including one or more parameters for tracking the position of the radio transmitter according to the received position signal and the unique number; And (c) in the location tracking center, processing the delay information data sent from each base station based on the location coordinates of the plurality of base stations installed on known coordinates to track the actual location coordinates of the wireless transmission apparatus. Characterized in that it comprises a step.

1 is a view showing the configuration of a terrestrial position tracking system according to the present invention

2 is a block diagram showing the configuration of the radio transmitting apparatus of FIG.

3 is a flowchart illustrating the operation of the radio transmitter of FIG.

4 is a block diagram showing the configuration of a base station of FIG.

5 is a flowchart illustrating the operation of the base station of FIG.

6 is a block diagram showing the configuration of the location tracking center of FIG.

7 is an operation flowchart of an active location tracking method according to the present invention.

8 is an operational flowchart of a passive position tracking method according to the present invention.

9 is a diagram for explaining a relative delay time when a position signal reaches a base station from a radio transmitter;

10 is a view for explaining a position estimation method of a wireless transmission apparatus using the relative distance measured from three base stations

<Explanation of symbols for the main parts of the drawings>

10: radio transmitter 20a, 20b, 20c: base station

30: location tracking center

Hereinafter, with reference to the accompanying drawings, a preferred embodiment of the ground position tracking method according to the present invention will be described in detail.

1 is a configuration diagram schematically showing a location tracking system of the present invention.

In FIG. 1, the location tracking system is composed of a radio transmitter 10, base stations 20a, 20b, 20c, and a location tracking center 30.

The radio transmitter 10 transmits a radio wave including a specific type of location signal for location tracking and a unique number for its identification at an arbitrary location in an area where radio reception is possible at a base station at any time. It is provided. The band used for the radio transmitter uses the VHF / UHF band.

Here, the location signal has a predefined shape so as to know the start point of the signal and the end point of the signal when it is received from a plurality of base stations and is continuously transmitted for a predetermined time. In addition, a unique number of the radio transmitter is added at the start or end of the position signal so that it is possible to distinguish which radio signal is the position signal of a radio transmitter even if a radio wave is received at a receiver base station.

The base station 20a, 20b, 20c receives and analyzes the radio wave transmitted from the radio transmitter 10, detects the position signal transmitted from a specific radio transmitter, measures the reception time of the position signal, and transmits radio. Compute the propagation delay time from the transmission of the device to the reception of the base station.

Each base station 20a, 20b, 20c receives only the position signal and the unique number of the radio transmitter 10 under a constant self delay condition. Depending on the received location signal and the unique number, the delay information data including one or more parameters for tracking the location of the radio transmitter is generated and sent to the location tracking center 30 for each reference time zone.

Here, the delay information data includes the delay time, a unique number of the radio transmitter and a unique number of the received base station.

On the other hand, in order to increase the accuracy of the delay information data, it is preferable to increase the carrier frequencies of the radio transmitter 10 and the base stations 20a, 20b, and 20c as much as possible. If you use the same frequency as the PCS, you will theoretically get 20cm to 40cm accuracy. However, in a cellular phone or a PCS, there is an error precision of an oscillator and an error necessary for detecting an internal signal of an actual electronic circuit, and thus a propagation delay error of about 40 m is generated. In order to minimize such errors, the present specification proposes to add a receiver delay time detection function, which will be described below.

The location tracking center 30 processes the delay information data sent from each base station based on the location coordinates of the plurality of base stations installed on the previously known coordinates to track the actual location of the radio transmitter.

For this purpose, the location tracking center 30 uses each delay information data received from a plurality of base stations 20a, 20b, 20c, ... through a period communication network (wireless period communication network), and each base station configured in advance. Based on the position coordinates of the base station receiving the position signal from the position information database, the position coordinates of the wireless transmission apparatus that has transmitted the position signal are calculated.

That is, the base station receives the location signal from the base station unique number included in the delay information data and the unique number of the radio transmitter, and the radio transmitter that transmits the position signal is distinguished, and each base station is relatively one radio transmitter. The relative distance of how far apart is located using the delay time data. Now, when the relative distance data is applied to the position coordinates of the base station, the position of one radio transmitter can be calculated.

In this way, it is possible to track the exact position of the radio transmitter using the delay information data obtained from a plurality of base stations, and display the position of the radio transmitter tracked on the numerical map displaying the position coordinates of the base stations of the computer monitor. Done. In addition, the positional coordinates of the tracked radio transmitter can be output as numerical values, which can be used for various applications.

In this regard, it is not known when the radio transmitter 10 transmits radio waves according to the received delay information data, and the delay time of the circuit itself for detecting the signal of the base station itself, the surrounding climate, temperature, humidity, etc. It is impossible to directly calculate the distance to the radio wave source directly from the delay information data because it includes a significant error depending on the conditions.

However, in the present invention, regardless of the magnitude of such error information or when the radio wave transmission device 10 transmits radio waves, the equivalent error is obtained by using delay information data received from at least three base stations 20a, 20b, and 20c. We propose a method of calculating a position from three or more distance information including a. This proposal can yield a theoretically very accurate position, as described in Figures 7-8 below.

FIG. 2 is a block diagram showing the configuration of the radio transmitter of FIG. 1, and FIG. 3 is a flowchart illustrating the operation of the radio transmitter of FIG.

Referring to FIG. 2, the wireless transmitter 10 includes a transceiver module 11 including a call signal receiver 11a and a signal transmitter 11b directly connected to a wireless network, a user interface 12, and a controller 13. ), A unique number generator (14), a position signal generator (15) and an antenna (15).

The call signal receiver 11a receives a call signal when calling the wireless transmitter 10 from a remote place by a third party's request, and transmits the call signal to the controller 13 to activate the wireless transmitter 10. To do that.

The user interface 12 is a part directly manipulated by the user to receive the position tracking start command of the device from the user and transmit the command to the control unit 13 to operate the wireless transmission device 10.

The control unit 13 is a device connected to the transmission / reception module 11 and includes software related to overall system operation of the wireless transmission device 10. The control unit 13 receives a start command from the user interface 12 or the call signal receiving unit 11a. The overall operation of the apparatus is started, and the hardware for driving each component of the radio transmitter is controlled.

The unique number generator 14 stores a unique number for identifying the wireless transmitter 10 or generates a unique number of the wireless transmitter according to a command of the controller 13. In addition, the unique number generation unit 14 is preferably configured to store a variety of information of the required device in addition to it can store and generate additional necessary data when using the function of the device in the future.

The position signal generator 15 receives a command from the controller 13 to generate a specific position signal for position tracking and transmits the signal to the signal transmitter 11b, and also receives a unique number of the radio transmitter from the controller 13. The signal is transmitted to the signal transmitter 11b.

The signal transmitter 11b converts the position signal and the unique number provided from the position signal generator 15 into a radio signal and transmits it through the antenna 16.

Meanwhile, the unique number may be provided directly to the signal transmitter 11b without passing through the position signal generator 15.

More preferably, the radio transmitter 10 is a personal mobile radio transmitter such as carried by a user or mounted in a vehicle. The hardware / software of the radio transmitter 10 is a conventional pager, cellular phone, or cellular device. It is simply installed or applied to a mobile communication terminal such as a phone.

In addition, it is manufactured to be easy to use by the mobile user, so that it is simple to use in case of emergency and instant location is realized, and it is manufactured to communicate by using the existing wireless communication network. Of course.

Referring to FIG. 3, the control unit 13 of the wireless transmission apparatus 10 is in a standby state and determines that there is a user's operation (101), or is not transmitting a position signal when a call signal is received. If it is determined (102, 112), the radio transmitter 10 is driven and controlled to generate a position signal through the position signal generator 15 (105).

The generated position signal is transmitted and continues for a predetermined time, and when the transmission is completed (106, 107), and transmits the unique number of the radio transmitter from the unique number generator 14 (108).

If the number of times of location signal and unique number transmission is specified, the process of generating and transmitting the location signal and unique number 105 to 108 and 111 is repeated (109, 111).

On the other hand, when receiving a call signal by a third party's request while transmitting a large number of location signals and unique numbers (102), since the location tracking from a remote location is not necessary, the radio transmitter 10 transmits the location signal. If it is determined that the transmission is in operation 112, the transmission of the position signal is stopped (113). By doing so, location tracking wireless network traffic can be efficiently operated.

When the process of transmitting the position signal and the unique number of the designated number of times in step 109 is completed, or when the position signal transmission in the step 113 is stopped, the control unit 13 of the wireless transmitter 10 initializes its own position signal generation. The device enters the standby state again to stop the operation.

4 is a block diagram illustrating the configuration of the base station of FIG. 1, and FIG. 5 is a flowchart illustrating the operation of the base station of FIG. 4.

Referring to FIG. 4, the base station 20a includes a delay time detector 21, a unique number discrimination unit 26, a receiver control unit 27, and a data network connection unit 28. As shown in FIG.

The delay time detector 21 amplifies the radio signal received from the antenna 21 and demodulates and detects the position signal included in the radio signal, and the time when the radio wave arrives from the detected position signal to the base station. The delay time determination unit 23 generates a self-delay signal for measuring the processing delay time of the circuit itself, and uses a self delay signal generated by the delay time determination unit 23. It consists of a magnetic delay discrimination unit 24 for generating a transmission radio signal and transmitting it to the signal reception unit 22. More preferably, the delay time detector 21 may further include a GPS reference time unit 25 to precisely synchronize time synchronization between a plurality of other base stations 20a, 20b, and 20c.

The unique number discriminating unit 26 analyzes the unique number of the radio transmitting apparatus from the detected signal of the signal receiving unit 22 to determine the radio transmitting apparatus 10 which transmitted the position signal.

The receiving device controller 27 includes software for operating the base station 20a, controls various hardware of the base station 20a, and transmits the data to be transmitted to the location tracking center 30 through the data communication network, that is, the wireless transmission device. Generate delay information data including the unique number, the delay time measured by the base station, and the unique number of the base station.

The data communication network interface unit 28 transmits the delay information data received from the receiving device control unit 27 to the data communication network 30 for each reference time zone. Here, the delay information data may be packetized and transmitted through the reception device controller 27.

Referring to FIG. 5, the base station 20a initializes the parameters of the system at the first operation (201), waits for signal reception from the radio transmitter 10 (203), and detects a signal on the reception channel. If not (204), the self delay check is performed (202), and returns to the signal reception standby state (203).

If a signal is received in the channel (204), the signal reception start time is collected and stored in seconds (205), and the time difference between the actual received signal is calculated and detected based on the received start time and the GPS reference time ( 207, the actual reception delay time data is calculated together with the self delay time data (208).

If it is confirmed that the position signal from the self delay time data and the actual reception delay time data (209), it is determined whether the unique number of the radio transmitter is defined by extracting the unique number of the radio transmitter (210).

As a result of the determination of step 210, if the extracted data is determined to be a signal different from or different from the configuration of the defined wireless transmitter unique number, self-delay check is performed again (202).

As a result of the determination of step 210, if the received data is a unique number of a defined wireless transmitting device, the unique number of the wireless transmitting device is extracted, the delay information packet data is generated and transmitted (212, 213), and then the received information is initialized ( 214), a series of position signal receiving processing is completed.

After step 214, the self-delay check step 202 is entered again to repeat a series of processes in order.

If necessary, the delay time data obtained in step 208 may be converted into a delay distance value 211, and the delay time data may be included in the delay information data for transmission.

6 is a block diagram showing the configuration of the location tracking center of FIG.

Referring to FIG. 6, the location tracking center 30 includes a data network connection unit 31, a base station data table 32, a radio transmitter device data table 33, a base station location database 34, and a location. It consists of a calculator module 35, a map display module 36, a location database 37 for each radio transmitter and a location tracking service application module 38.

The data network connection unit 31 is connected to the data network and is in charge of data communication.

The base station-specific data table 32 analyzes the data received from the plurality of base stations 20a, 20b, and 20c through the data network connection unit 31, classifies each base station, and transmits the packet data sent from each base station by radio transmitter. In addition, it has a function to table the delay information data for each signal reception time.

The radio transmission apparatus-specific data table 33 has a function of classifying and tabulating the base station, the signal reception time, and the delay information data for each radio transmission apparatus from the base station-specific data table 32 for each radio base station.

The base station location database 34 stores the position coordinates of each base station built in advance, and provides the position calculator module 35 with data on the location information of the base station provided from the base station-specific data table 32.

The position calculator module 35 uses a plurality of position coordinate information provided from the base station position database 34 and each delay information data provided from the data table 33 for each radio transmission device, according to the position calculation algorithm. ) Is calculated and printed. That is, the delay time of the position signal of the delay information data received for each reference time zone is converted into relative distance data to calculate the position coordinates of the radio transmitter based on the position coordinates of the base station (see FIG. 8).

The map display module 36 displays the calculation result of the position calculator module 35 on the map.

The location database 37 for each radio transmitter receives the output result from the position calculator module 35 and stores the location tracking result for each tracking time for each radio transmitter.

The location tracking service application module 38 uses the result in connection with the location calculator module 35, the location database 37 for each wireless transmitting device, and the map display module 36, and the application in the location tracking center 30. It can control various modules linked to the unit and has the function of transmitting location tracking result to the service application user through the communication network.

As such, the location tracking system can be installed separately from a plurality of base stations or by building a location tracking center, so that emergency situations of emergency patients who need to look for lost children, silver towns, and health at all times in the amusement facilities used by many people Location tracking at the time of occurrence, car anti-theft system to prevent theft of the car, fire alarm system that automatically informs the location of the fire in the event of a fire, accident alarm system that automatically informs the location of the car accident in the event of a car accident, etc. It can be used for an active location tracking system.

In addition, by implementing a location tracking system on a general mobile communication device can be utilized in a passive location tracking system that can track the location only when the location tracking needs of the radio transmitter.

7 is a flowchart illustrating an active location tracking method of the present invention.

In the present specification, active location tracking is performed by a person carrying a wireless transmission device by using a procedure as described with reference to FIGS. 1 to 6 according to the purpose of operating the actual location tracking. It is used to actively announce its position by the automatic start operation of the machine using the device (e.g. in case of emergency or emergency).

First, in the radio transmitting apparatus 10, the mobile device starts the operation and transmits the position signal and the unique number (301, 302).

The neighboring base stations 20a, 20b, 20c, ... wait for signal reception through the receivers 22 and analyze the received signal as shown in steps 205 to 208 of FIG. If received (303, 304), the time of arrival of the position signal and the unique number of the radio transmitter are detected, and the delay time of the position signal is calculated from the arrival time.

Delay information data including the location signal arrival time, the unique number of the radio transmitter and the unique number data of the base station is packetized and transmitted to the location tracking center 30 (305, 306). The delay information data may further include delay distance data converted from the delay time.

The location tracking center 30 receives packet data from each of the base stations 20a, 20b, and 20c (307), and provides a delay information table such as a plurality of delay information tables 308 for each base station and a reception time for each radio transmitter (see FIG. 309).

The unique number of the base station belonging to the delay information data for each radio transmission device is passed to the previously established position coordinate database for each base station, and the position coordinate data of the base station is read (310).

Now, the position calculator module 35 calculates the position of the radio transmitter using the delay information for each base station and the delay information for each transmitter, based on the position coordinate data for each base station (311), and maps the result. It is stored in the screen display and the user location DB (transmitter location database) (312, 313).

The location result of the transmission device stored in the user location DB is transmitted to the service user who needs to move to the location of the wireless transmission device that transmitted the location signal in case of an emergency (314).

8 is a flowchart illustrating a passive location tracking method of the present invention.

The passive position tracking in this specification is intended to inform the third party of the location of the radio transmitter portable device by performing a process as described in FIGS. 1 to 6 by operating the radio transmitter at the request of a third party. When used.

First, when the service user registered in the location tracking center 30 requests the location tracking of the wireless transmission device (401), the information of the tracking target wireless transmission device is registered in the storage device (402), and the wireless transmission is performed through the wireless network. The device 10 is called (403).

The radio transmitter 10 receives a call for location tracking (404) until it generates a predetermined location signal and its own unique number and transmits it to a nearby base station (405).

The neighboring base stations 20a, 20b, 20c, ... are waiting for signal reception at each receiver 22 (406) and when a position signal is received (407), the position signal arrival time and the uniqueness of the radio transmitter. Detecting the number and calculating the reception delay time to generate the delay information data including the location signal arrival time, the unique number of the wireless transmission device, the reception delay mountain and the unique number data of the base station and make the packet data (408) location tracking center And transmits to (30) (409).

The location tracking center 30 receives delay information packet data from each base station 20a, 20b, 20c (410), and a plurality of delay information tables 411 for each base station and a delay information table 412 for each radio transmitter. Classify as The unique number of the base station belonging to the delay information data for each radio transmitter is passed to the previously established position coordinate database for each base station, and the position coordinate data of the base station is read (413).

Now, the position calculator module 35 calculates the position of the radio transmitter using the delay information for each base station and the delay information for the radio transmitter based on the position coordinate data for each base station (414). It is stored in the map screen indicator and the user location DB (transmitter location database) (415, 416).

The location result of the transmitter stored in the user location DB is transmitted to the service user who needs to move to the location where the location signal was transmitted in case of an emergency (417).

The fundamental difference from the active location tracking of FIG. 7 is that location tracking is initiated at the request of the service user. In addition, the purpose of use is not in an urgent state, but can be used for the purpose of tracking the location of the application if necessary, for example, to track the location of moving vehicles or personnel, animals, objects, etc. The characteristic of this operation method is that the purpose of the operation can be tracked without knowing the position tracking situation at the position of the radio transmitter.

7 and 8 can be used by dividing the operation method in the existing location tracking system.

However, in some cases, it is necessary to use a lot of power of the transmitter at all times in order to make it difficult to carry or to carry or attach the radio transmitter, the complexity of use, and to immediately position at any time. After the location tracking calculation is performed in the device itself, it is necessary to use a wireless communication network.

In the present invention, since the location calculation is performed in the location tracking center without the location tracking calculation in the wireless transmission apparatus, it is fundamentally different from the conventional location tracking operation method.

In addition, although the conventional method may not be able to perform the location tracking according to the strong noise around the location tracking device, in the case of the active location tracking method proposed in the present invention, even if a very urgent situation occurs, the radio transmitter may detect the location signal. Since only a transmission method is required, a relatively reliable location tracking method is possible.

9 is a diagram for explaining the relative delay time when the position signal reaches the base station from the radio transmitter, and FIG. 10 illustrates a method for calculating the position of the radio transmitter using the relative distances measured from three base stations. It is a figure for following.

Referring to Fig. 9, it is assumed that the position signal transmission start time composed of specific format data in the radio transmitter 10 is T0, and the duration of the position signal is Tdat. Further, assume that the synchronization time output of the GPS standard time apparatus at the base station 20a is T1, and the time at which the transmitted position signal reaches the base station and is actually detected is T2.

Theoretically, the base station 20a can obtain the delay distance L between the radio transmitter and the base station by using the delay time Tdob which actually takes to reach the position signal transmitted from the radio transmitter as shown in Equation 1. have.

(C = 299,792,458 m / sec)

Here, Tdob is a delay time during propagation of actual radio waves, and the speed of radio waves in the air is equal to the speed C of light.

However, since Tdob is a value that cannot be measured, the relative delay time Trel that can be measured by the base station is used. The relative distance is obtained from this relative delay time. This corresponds to the relative distance from the transmitter to at least three base stations, not the absolute distance, and can be collected at the location tracking center to track the absolute position of the transmitter.

Then, the relative delay time Trel corresponds to the remaining time obtained by subtracting the self delay time Tdck in the base station circuit from the delay time Tdms measured by the base station, as shown in Equation (2).

Here, Tdms is T2-T1.

Now, a method of calculating the distance from the location tracking center 30 to the radio transmitter 10 will be described with reference to FIG.

1. Referring to FIG. 10A, the calculated distances from the radio transmitter to three base stations B1, B2, and B3 are referred to as L1, L2, and L3. If the coordinates of each base station in two dimensions are (x1, y1), (x2, y2), and (x3, y3), then the coordinates of the radio transmitter are the radius L1, L2 of the coordinates of each base station as the center of the circle. , The position A (x, y) of the intersection of three circles, L3.

2. Although not shown, in order to calculate the position in the three-dimensional space, the coordinates of each base station are three-dimensional coordinates {xn, yn, zn}, and the distances L1, L2, L3, The intersection (x, y, z) of the sphere with L4 as the center of the sphere becomes the position coordinate of the radio transmitter.

3. Now, referring to (b) of FIG. 10, distance calculation using the relative annual time Trel measured and calculated by the base station 20a is the same as the calculation method of 1, but the intersection of three circles can be obtained. none. This is because the distance calculated from the relative delay time Trel is a result of calculating the time at which the radio transmitter transmits the radio wave in an unknown state.

Therefore, in this case, without using the actual distance to the radio transmitter, each relative distance L ', L' '(= relative time x C) is the radius of the circle, and the coordinates of each base station are the center of the circle (B1, B2 and B3) find one circle and the circle inscribed in the arc of three circles, the center of the circle becomes the exact two-dimensional position coordinate (A) of the radio transmitter.

Although not shown, in order to find the position of the radio transmitter in the three-dimensional space, a sphere with a radius of a relative distance measured from each base station centered on each coordinate of four or more base stations is drawn on the surface of each sphere. When the center of the inscribed sphere is found, the center of the sphere becomes the exact position coordinate in space of the radio transmitter.

The relative distance Lrel at this time is calculated as in Equation 3 below.

However, when the absolute time received for each base station receiving the position signal is measured before and after the GPS reference time, the relative distance may be negative in Equation 3 (when T _dck &gt; T _dms ). Calculating as can yield accurate calculation result.

Of course, when the reception of radio waves is impossible, the relative distance cannot be calculated.

On the other hand, when there is a radio wave obstacle, a specific method of tracking the position of the transmitter is based on a signal reaching the shortest time among the multi-paths of the received radio waves reflected by various obstacles, although it is an obstacle to accurate location tracking when there is a radio wave obstacle. Calculating the relative distance for the position calculation enables the position tracking with the minimum error.

In this case, if the difference between the total propagation distance of the multipath and the linear distance between the radio transmitter and the base station is L _diff , the position calculation error due to the multipath is about 1/2 L _diff .

In order to reduce the error caused by the multipath, it is preferable to install the installation location of the base station at a high position so as not to make one reflected wave as much as possible.

The present invention is not limited to the embodiments described above, and various modifications and changes can be made by those skilled in the art, which are included in the spirit and scope of the present invention as defined in the appended claims.

As described above, the present invention is easy to manufacture a wireless transmission apparatus that is the target of location tracking, and can be used by adding software to transmit a location signal to an existing digital cellular phone or PCS.

The active / passive location tracking method proposed by the present invention facilitates the location tracking of the object by carrying the wireless transmission device to a patient or a mum who is in an emergency state of health, and always provides location tracking for wireless location tracking. It does not need to supply the power of the device, while using the transmission power only when the location tracking needs, compared to the existing location tracking device takes a relatively small tracking time, there is an advantage that the position tracking immediately after the location tracking request occurs.

In addition, in a state where radio waves can be transmitted to three or more base stations of an existing wireless communication network even under conditions such as indoor obstacles, indoors, tunnels, basement floors, forests, or under roadside trees, the relative distance may be used. This has the advantage of finding a relatively accurate location.

The present invention can be installed separately by the base station, and by establishing a simple location tracking center 30, the emergency of emergency patients of the need to look for the lost in the amusement facilities used by many people, Silver Town and always the state of health Location tracking in the event of a situation, vehicle anti-theft system to prevent theft of the car, fire alarm system to automatically inform the location of the fire in case of fire, accident alarm system to automatically inform the location of the car accident in the event of a car accident, etc. It can be used for active location tracking system.

In addition, by implementing a location tracking system on a general mobile communication device can be utilized in a passive location tracking system that can track the location only when the location tracking needs of the radio transmitter.

Claims (12)

A wireless transmission device for transmitting a specific type of location signal for location tracking, a plurality of base stations receiving the location signal, and a location tracking center for communicating with the plurality of base stations to track the position coordinates of the wireless transmission device In the location tracking method in the system, (a) transmitting the position signal and a unique number of the radio transmitter by driving the radio transmitter according to the purpose of the location tracking; (b) generating and transmitting, at the plurality of base stations, delay information data including one or more parameters for tracking the position of the radio transmitter according to the received position signal and the unique number; And (c) tracking the actual position coordinates of the wireless transmitter by processing the delay information data sent from each base station based on the position coordinates of the plurality of base stations installed on the coordinates known in advance in the position tracking center; Terrestrial location tracking method comprising a. The method of claim 1, wherein step (a) A ground position tracking method, characterized in that it is driven by a start operation of a person carrying the radio transmitter or an automatic start operation of a machine using the radio transmitter and / or driven by a call request of a third party. The method of claim 1, wherein the position signal of step (a) measures the start time of the data and the end time of the data in the demodulation process at the time of reception, thereby calculating the delay time from the time of transmission of the position signal to the time of reception. Terrestrial position tracking method characterized in that the signal of a predetermined type to be predefined. The method of claim 1, wherein step (a) And transmitting the position signal and the unique number of the radio transmitter in a predetermined number of times for a predetermined period. The method of claim 2, wherein step (a) And in the location tracking center in response to a call request from a third party, registering information of the tracked wireless transmitting device and transmitting a call signal. The method of claim 1 or 2, wherein step (a) And terminating the transmission of the location signal when receiving a call request signal from the third party while transmitting the location signal and the unique number of the radio transmitter. The method of claim 1, wherein step (b) (b1) analyzing the received radio wave to detect a position signal and determine whether the position signal is a defined position signal; (b2) In the case of the defined position signal, the arrival time and the delay time of the position signal are detected for each unique number of each radio transmitter, and the arrival time and delay time together with the unique number for base station identification and Generating delay information data including a unique number; And (b3) terrestrial location tracking method comprising the step of transmitting the generated delay information data to the location tracking center. 8. The terrestrial location tracking method according to claim 7, wherein the step (b3) further comprises the step of packetizing and transmitting the delay information data. The method of claim 1, wherein step (c) (c1) analyzing the data received from the plurality of base stations, classifying the data into the base stations, and classifying the data sent from each base station into delay information data for each radio transmission apparatus and signal reception time and table the data firstly; (c2) receiving the first tabled data and reclassifying the information into delay information data for each base station and signal reception time for receiving the location signal for each of the wireless transmitters, and performing a second table; (c3) constructing a base station location database that stores location coordinate data of each base station built in advance and provides location coordinates of a corresponding base station that has received the identified location signal from the primary tabled data; And (c4) calculating the actual position coordinates of the corresponding radio transmitter by using the delay information data of the data for each radio transmitter apparatus tabled on the basis of the position coordinates of the provided base station. Ground position tracking method. The method of claim 1, wherein step (c) And displaying the location coordinate result of the wireless transmission device on a map. The method of claim 1, wherein step (c) And establishing a location database for each radio transmitter that stores the result of the positional coordinates of the radio transmitter as the result data of the tracking time for each radio transmitter. 12. The method according to any one of claims 9 to 11, wherein step (c) In connection with the position coordinate calculation step and / or the map display step and / or the location database construction step for each transmitter, the output result of the one or more steps is used, and in conjunction with a separate application unit, various location tracking services can be established. Ground location tracking method further comprising the step of providing a location service provided to the service user through.