KR20110042596A - Mia tracking system and location tracking method - Google Patents

Abstract

A lost tracking system and method are provided that can generate a lost signal immediately upon occurrence of lost and provide the initial location of the lost to track the lost location quickly and accurately. The Mia tracking system is a beacon device that acts as a coordinator of the ZigBee protocol and acts as a network generator carried by the guardian, as an end device of the Zigbee protocol, and carried by the custodian. And a connection relay point that acts as a coordinator of the Zigbee protocol and forms a lost communication network with the lost signal generator when a lost child occurs, and a lost tracking center that stores and analyzes data transmitted from the connected relay point. have. Here, the MIA signal generator configures a communication network with the network generator using a general wireless personal area network identifier (PANID), and automatically determines that the MIA signal is unique to the MIA signal. A communication network can be formed with the access relay point by using the Rescue PANID.

Mia, Location Tracking, ZigBee, Wireless Personal Area Network (WPAN), PANID

Description

MIA tracking system and location tracking method {SYSTEM AND METHOD FOR PURSUIT OF A LOST CHILD}

The present invention relates to a lost tracking system and method, to provide a lost tracking system and method that can be notified immediately of the occurrence of the missing and provide the initial location of the missing.

Recently, in order to quickly rescue a rescue requester in situations such as a lost child, abduction and distress (hereinafter referred to collectively as a lost situation) based on the development of wireless communication, the rescue requester receives a predetermined position signal from the rescue requester. A location tracking system that tracks the location of a person is becoming popular. As an example of a location tracking system, a guardian possesses a pair of the MIA signal generator and a pair of network generators carried by a guardian, such as a child, and the MIA tracking system that informs the guardian of the guardian's location through the MIA signal generator when a child is lost. have.

However, in the case of a lost child tracking system, when the lost child has to operate the lost signal generator directly, it is cumbersome to know how to use the lost signal generator in advance. Only after this has elapsed, it may be difficult to generate a signal to track the location of the subject. Likewise, if the guardian does not recognize the situation immediately after the occurrence of the lost child, and the situation is recognized after a certain time has elapsed, the information on the time and place of the lost child is unclear and the accuracy of tracking the location of the lost child is poor and takes a long time. .

In addition, there is a need for a positioning technology that guarantees the reliability of the generation, transmission and reception of emergency signals and the accuracy of the location of signal generation in a lost child tracking system. Currently, the positioning technology has errors ranging from tens of meters to several kilometers. The range is very large. When the positioning technology using the GPS (Global Positioning System) is used, the error is reduced to within a few meters, but it is difficult to use and reliability problem in the complex terrain where the GPS signal does not reach, or in a lot of shaded areas and high-rise buildings. In addition, the existing positioning technology needs to maintain continuous communication with the surrounding communication network, so the more the number of devices participating in the communication, the more the load increases and the processing speed of the entire communication network can be reduced, and the number of repeaters for operating the base station or sensor network increases. There is a problem that should be.

Embodiments of the present invention for solving the above-mentioned problems are to provide a tracking system and method that can generate a lost signal as soon as the lost occurs.

In addition, the present invention provides a lost tracking system and method capable of actively processing a lost signal by generating a lost signal by detecting a lost child even if the guardian does not directly operate the lost signal generator.

In addition, it is to provide a lost tracking system and method for providing a location of the guardian when the lost occurs to accurately and quickly track the location of the lost.

According to the embodiments of the present invention for achieving the above object of the present invention, the lost tracking system that can quickly and accurately track the location of the lost by generating a lost signal immediately after the occurrence of the lost and provides the initial position of the lost , A network generator operated by a coordinator of the ZigBee protocol and carried by a guardian, a beacon device which acts as an end device of the ZigBee protocol and is carried by a custodian, It may be configured to include a connection relay point that acts as a coordinator of the Zigbee protocol and forms a lost communication network with the lost signal generator when a lost child occurs, and a lost tracking center that stores and analyzes data transmitted from the connected relay point. Here, the MIA signal generator configures a communication network with the network generator using a general wireless personal area network identifier (PANID), and automatically determines that the MIA signal is unique to the MIA signal. A communication network can be formed with the access relay point by using the Rescue PANID. That is, the MIA signal generator may selectively participate in two networks, the network generator and the access relay point, while switching the general PANID and the Rescue PANID according to a situation.

Here, the MIA signal generator may form a communication network with the network generator using a normal PANID in a normal state, and may form a communication network with the access relay point using a Rescue PANID in a lost state. In addition, the lost signal generator may include a signal controller for increasing a transmission output to form a communication network with the connection relay point in the lost occurrence state. The communication network generator may include a controller configured to measure a distance from the lost signal generator to a lost signal generator using a received signal strength when the communication with the lost signal generator becomes impossible. In addition, the communication network generator may include an alarm unit for informing the guardian of the occurrence of the lost when the lost.

The access point may be operated in the form of a fixed station or mobile station of a communication network. Here, in the case of a connection relay point operating in the form of a mobile station, an alarm unit may be provided to notify a user operating the connection relay point of occurrence of a lost child. In addition, the access point may transmit data to the Mia tracking center using a communication network capable of data communication, including a mobile communication network, a wireless data communication network.

On the other hand, according to other embodiments of the present invention for achieving the above object of the present invention, the lost location tracking method for generating a lost signal immediately upon occurrence of lost and provide the initial location of the lost, the general PANID of the Zigbee protocol Forming a communication network by using a lost signal generator and a communication network generator, determining whether a lost child occurs when communication between the lost signal generator and the network generator becomes incapable, and automatically determining the lost signal when it is determined that the lost signal is generated. Transmitting a MIA network join request signal to an access relay point using a Rescue PANID, forming a MIA network by receiving the MIA signal generator and a connection relay point receiving the MIA network request signal from the access relay point; Analyze MIA network request signal and collect device information The method may include: transmitting the collected device information to a lost tracking center, storing and analyzing the device information transmitted from the access relay point at the lost tracking center, and tracking the location of the lost signal generator. Can be configured.

Here, the MIA signal generator transmits a device information signal and the communication network generator communicates by transmitting a response signal to the device information signal, and the response signal is not received by the MIA signal generator for a preset time. If not, it can be judged as a lost situation. The device information may include a unique number of the lost signal generator and time information of transmitting and receiving the device information signal.

In addition, the mia signal generator may attempt to recombine the communication network using the network generator and the general PANID after forming a communication network with the access relay point using the Rescue PANID for a predetermined time.

In an embodiment, the location tracking of the MIA signal generator may include receiving a MIA network request signal transmitted from one MIA signal generator at a plurality of access relay points, and at the plurality of access relay points. Computing the moving path of the lost based on the record of the position of the connection relay point that the communication network was formed.

As described above, according to the embodiments of the present invention, by using the signal strength according to the distance between the guardian and the child having a pair of the MIA signal generator and the communication network generator, the MIA signal immediately after the occurrence of the MIA without additional manipulation It can effectively cope with the occurrence of missing children.

In addition, ZigBee can be used to form a low-power, low-cost, ultra-small mia signal generator, and also has a packet structure suitable for emergency signal transmission and has a high power efficiency, so that it can be maintained for a long time. It is effective to track its location.

In addition, unlike ZigBee, ZigBee enables signal generation and continuous communication regardless of where the ward is.

In addition, since the near position of the lost child is provided through the relay connection point when the lost child occurs, the initial position of the lost child tracking can be effectively selected using the active position detection method, and the lost child location tracking is easy.

In addition, not all communication networks are connected as a whole, but only between the guardian and the guardian and participating in the entire network only in the event of a loss, thereby reducing the load on the communication network.

In addition, since the Mia tracking system can be operated using only a few access relay points, it is unnecessary to add a base station or repeater, and the operation efficiency and cost can be reduced.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, but the present invention is not limited to or limited by the embodiments. In describing the present invention, a detailed description of well-known functions or constructions may be omitted for clarity of the present invention.

Hereinafter, referring to FIG. 1, a lost tracking system 100 according to an exemplary embodiment of the present invention will be described in detail. For reference, FIG. 1 is a schematic diagram of a lost child tracking system 100 according to an embodiment of the present invention, and FIG. 2 shows a lost signal generator 110 for explaining the operation of a steady state in the lost child tracking system 100 of FIG. ) Is a block diagram showing the operation of the communication network generator 120, and FIG. 3 is a connection of a lost signal generator 110 and a lost communication network for explaining the operation of the lost communication network in a lost state in the lost tracking system 100 of FIG. A block diagram showing the operation of the relay point 130 is shown.

Mia tracking system 100 is a Mia signal generator 110, a communication network generator 120, a connection relay point 130, the Mia tracking center 140 is composed of a pair of the guardian and the guardian each portable and Zigbee communication is possible And it may be composed of a tracking team 150 for tracking and rescue the location of the Mia by the request of the Mia tracking center 140.

Mia signal generator 110 and communication network generator 120 is a pair of communication with each other is a device that can be checked whether or not a missing child by carrying each of the guardian and guardian to transmit and receive signals to each other. In addition, the mia signal generator 110 and the network generator 120 is formed of a small and simple structure for easy portability.

Here, the lost signal generator 110 operates as an end device of the ZigBee protocol and includes a signal controller 112, a signal generator 114, and an eye device modem 116. The network generator 120 operates as a coordinator of the Zigbee protocol and includes a signal generator 126, a controller 124, and a guardian device modem 122. Since the MIA signal generator 110 and the network generator 120 are short-range communication modules capable of communicating with peripheral devices within a predetermined distance using ZigBee, the MIA signal generator 110 and the network generator 120 may communicate with each other. If out of range, communication is disabled. The lost tracking system 100 according to the present embodiment reduces the strength of the received signal when the pair of lost signal generator 110 and the network generator 120 separated from each other by a predetermined distance by using the short range communication characteristics of the Zigbee communication. It is possible to determine that a lost child has occurred from being unable to communicate or to communicate with each other, and that a lost person can be notified even if the guardian or the guardian does not operate the device separately.

Referring to FIG. 2, the MIA signal generator 110 and the communication network generator 120 communicate with each other continuously using a general PANID. Here, the PANID is a wireless personal area network identifier (hereinafter referred to as a 'PANID') and is for transmitting a general Zigbee signal. On the other hand, when a lost child is used, a wireless personal area communication network unique number (hereinafter referred to as "Rescue PANID") for a lost child signal is used. That is, the MIA signal generator 110 may selectively participate in two networks of the communication network generator 120 and the access relay point 130 while switching between the general PANID and the Rescue PANID according to a situation.

In detail, when the lost signal generator 110 and the network generator 120 operate, the control unit 124 of the network generator 120 prepares for generating a network using a general PANID. When a communication network is formed between the MIA signal generator 110 and the communication network generator 120, the device information signal T1 is generated by the signal generator 114 of the MIA signal generator 110 operating as an end device, and the child device modem is generated. 116 transmits the device information signal T1 to the guardian device modem 122. Here, the device information signal T1 includes information such as a unique number for identifying the lost signal generator 110 and the time when the signal is transmitted.

The network generator 120 obtains device information about the corresponding MIA signal generator 110 from the control unit 124 using the device information signal T1 received from the guardian device modem 122, and uses the received signal strength to lose the information. The distance from the signal generator 110 is measured, and data such as the presence or absence of a signal and the unique number of the lost signal generator 110 are obtained. If the distance measured by the control unit 124 of the network generator 120 is far from the received signal strength or the lost device information signal (T1) signal does not exist for a predetermined time or more, it is determined that the lost situation occurs to the guardian Can be informed. For example, an alarm unit (not shown) may be provided that may notify the guardian of a lost child by vibrating, sounding, and lighting or displaying a lamp.

When the communication network generator 120 receives the device information signal T1, the signal generator 126 transmits an acknowledgment signal (ACK, acknowledge, T2) to the device information signal T1 to the lost signal generator 110.

Here, the signal controller 112 may determine that the terminal is in a lost state when it does not receive the response signal T2 even though it attempts to communicate with the communication network generator 120 for a predetermined time. When the response signal T2 is not received in this manner, the lost signal generator 110 is switched to a lost state, and as shown in FIG. 3, the connection relay point 130 around the lost signal generator 110 is connected to the lost signal generator 110. By communicating, you can attempt to join the MIA network.

Referring to FIG. 3, the lost signal generator 110 switched to the lost state participates in the wireless personal area communication network for the lost signal using the Rescue PANID in the signal controller 112, and the signal generator 114 and the child device. Modem 116 sends a MIA network request signal T3 to indicate this. In this case, the MIA signal generator 110 may increase the transmission output of the MIA network connection request signal T3 and transmit the MIA signal when the communication with the access point 130 is performed.

The connection relay point 130 continuously receives the MIA network join request signal T3, and operates as a coordinator of the MIA network continuously receiving only the MIA network join request signal T3 in the Rescue PANID region. In 132, the MIA network is configured by transmitting the response signal T4 to the MIA signal generator 110 in response to the MIA network request signal T3.

On the other hand, when the MIA network is configured, the signal information detector 134 of the access relay point 130 analyzes the received MIA network request signal T3 to identify the unique number of the MIA signal generator 110 and the MIA network request signal ( Data such as the transmission / reception time of T3) and the unique number of the connection relay point 130 can be extracted. The extracted data is transferred to the information transmitter 136 and transmitted to the lost child tracking center 140 for the lost child using various communication methods such as a mobile communication network or a wireless local area network.

Here, the connection relay point 130 may be operated in the form of a fixed station 130a or a mobile station 130b of the communication network. That is, the access point 130 may be operated in the form of a fixed station (130a), such as a repeater or base station of the communication network, or in the form of a mobile station (130b) that can be carried by security personnel or employees who manage the area It can be operated as. And when operating the connection relay point 130 in the form of a mobile station (130b) may be provided with an alarm unit (not shown) for notifying in a manner such as vibration or sound, and lighting of the lamp to notify when the lost.

The Mia tracking center 140 stores and analyzes the data transmitted from the access relay point 130 and transmits the data to the tracking team 150 for tracking the location of the lost child to track the location of the lost child.

Hereinafter, referring to FIG. 4, a method of tracking a location of a lost child for determining whether a lost child is generated and finding a lost child in the lost tracking system configured as described above will be described.

First, the lost signal generator 110 and the network generator 120 forms a communication network using the general PANID (S1). Here, the step of forming the communication network is made by selecting the most appropriate frequency band according to the Zigbee protocol, the detailed technical configuration of the frequency band selection and communication method according to the Zigbee protocol can be understood from a known technique and the gist of the present invention. Since detailed descriptions and illustrations are omitted.

Next, in step S2 of determining whether a lost child is generated, determining whether to maintain a communication network between the lost signal generator 110 and the communication network generator 120 by determining the response signal T2 of the wireless personal area communication network WPAN. It can be determined by the reception. Here, in the lost generation determination step (S2), when the reception strength of the response signal T2 is weakened or communication is not possible for a predetermined time in the communication network generator 120, the signal controller 112 determines the normal / lost state. After the determination, the lost signal generator 110 is switched to the lost state.

Here, in the step S2 of determining whether there is a missing child, the response signal T2 may be received again after a predetermined time, and when the response signal T2 is received after a predetermined time, the existing communication network is maintained. This is because in the lost signal generator 110 or the network generator 120, a temporary communication disconnection may occur due to surrounding interference or radio wave interference. As such, the temporary response signal (T2) non-receipt state due to a communication problem is not a lost situation. Therefore, after a predetermined time, the communication is attempted again to check whether the response signal (T2) is received. The situation can be prevented from being judged. After a certain time, when the MIA signal generator 110 attempts to communicate again, but the response signal T2 is not received, it is determined that the Mia occurs.

Next, when it is determined that the lost signal generator 110 is a lost situation, the lost signal generator 110 transmits the lost communication network combining request signal T3 using the Rescue PANID (S3). The signal controller 112 of the lost signal generator 110 increases the transmission output and transmits the lost communication network combining request signal T4 to the access relay point 130 using the Rescue PANID.

Here, the lost signal generator 110 increases the output power only when the lost signal occurs, thereby participating in the communication network with the peripheral access relay point 130, thereby reducing the load added to the communication network and increasing the processing speed of the communication network. In addition, since the output of the MIA signal generator 110 is increased to form a communication network, the additional configuration of the connection relay point 130 for eliminating the shadow area of the repeater is unnecessary, so that the configuration of the MIA tracking system 100 is eliminated. It is possible to reduce the number of operations of the connection relay point 130 for.

Next, the connection relay point 130 continuously receives the MIA network join request signal T3 using the designated Rescue PANID (S10), and receives the MIA network join request signal T3 when the MIA network join request signal T3 is received. Analyze (T3) to collect information (S12).

Here, the connection relay point 130 receiving the MIA network request signal T3 forms a MIA network with the corresponding MIA signal generator 110 (S11), and immediately after forming the MIA network (S11), the received MIA network is received. The coupling request signal T3 is analyzed to collect information such as the unique number of the MIA signal generator 110, the transmission / reception time of the MIA network coupling request signal T3, and the unique number of the corresponding access relay 130 (S12). .

In addition, in the process of collecting information, a plurality of access relays 130 may participate in such information collection. Alternatively, the MIA network request signal T3 may be received by another MIA signal generator 110 at the connection relay point 130 at which the MIA network request signal T3 is received. In this case, the MIA network coupling may also be described. By repeatedly performing the steps of receiving and analyzing the request signal T3 (S10 ˜ S12), a plurality of lost signal generators may be involved in the lost communication network at one access relay point 130.

Here, the connection relay point 130 may be operated in the form of a fixed station (130a) or a mobile station (130b), when operating in the form of a mobile station (130b) may be provided with an alarm unit (not shown) for notification of the occurrence of missing. have.

On the other hand, the MIA signal generator 110 that has transmitted the MIA network connection request signal (T3) for a predetermined time after providing the device information to the connection relay point 130, and out of the connection relay point 130 for operating the corresponding MIA network Attempts to recombine the communication network generator 120 and the communication network using the existing PANID (S4). At this stage, if the network recombination succeeds, the existing network is maintained in step S1. If the recombination fails, the process returns to step S3 to increase the transmission power and transmits the MIA network request signal T3 to the access relay point 130 again. .

As described above, a plurality of pieces of missing information may be collected at one access relay point 130 through the steps of transmitting the missing network join request signal T3 and attempting to recombine with the network generator 120. In addition, when the Mia is moved to form a MIA network in the different MIA network connection relay 130 by time, it is possible to infer the path of the MIA to actively track the location of the MIA.

Next, the information analyzed by the access relay point 130 is transmitted to the lost tracking center 140 (S13). The transmission of information may be various methods such as a mobile communication network or a wireless local area network, and the present invention is not limited thereto. Substantially various communication methods for transmitting and receiving radio waves and information may be used.

Next, the lost tracking center 140 stores and analyzes the transmitted information (S14), and determines the location of the final received signal transmitted from the lost signal generator 110 based on the received information and the processed / stored information. In this way, the predicted position is selected as the initial position for tracking the lost position. In addition, the analyzed information may be transmitted to the tracking team 150 to track the location of the lost child at the predicted location (S15).

In addition, the Mia tracking center 140 and the tracking team 150 may track and rescue the Mia quickly using an additional tracking method based on the initial position.

According to the embodiments of the present invention, a pair of network generator 120 and a MIA signal generator 110 are configured to be provided by the guardian and the guardian by using ZigBee having the characteristics of near field communication. If communication between the lost signal generator 110 and the network generator 120 is not performed using the signal strength according to the distance between the guardians, it is determined that the lost situation occurs and generates a lost signal, so that the lost child can be immediately recognized. . In addition, even if the guardian or the guardian does not operate the device, it is possible to detect and track the occurrence of the missing child to effectively cope with the situation.

In addition, according to embodiments of the present invention, the advantages of low power, low cost, and small size, which are characteristics of ZigBee, can be efficiently used, and since it is easy to carry, it can be effectively used for tracking the location of lost children and lost children. By using Zigbee, it is possible to generate signals accurately even in indoor or shadowed areas where GPS cannot be used. In addition, ZigBee has a structure suitable for transmitting information configurable as a short packet such as a lost signal, and has a high power efficiency, so that it can maintain a communication state for a long time and continuously communicate until a lost child is found.

In addition, when a lost child is provided, a short distance location of the lost child can be selected by using the connection relay point 130 located near the lost child, and the initial position of the lost child can be selected, and the lost child signal generator 110 and the lost child communication network are formed. Through the relay point 130 information, the movement path of the lost child can be predicted so that the lost child can be accurately and quickly tracked.

In addition, since communication is performed only between the MIA signal generator 110 and the communication network generator 120 in general, the MIA tracking system can be configured without increasing the load on the communication network and without increasing the cost of adding a repeater.

As described above, the present invention has been described by specific embodiments such as specific components and the like, but the embodiments and the drawings are provided only to help a more general understanding of the present invention, and the present invention is limited to the above-described embodiments. In other words, various modifications and variations are possible to those skilled in the art to which the present invention pertains. Therefore, the spirit of the present invention should not be limited to the above-described embodiments, and all the things that are equivalent to or equivalent to the scope of the claims as well as the claims to be described later belong to the scope of the present invention.

1 is a schematic diagram for explaining a lost child tracking system according to an embodiment of the present invention;

FIG. 2 is a block diagram illustrating an operation between a lost signal generator and a network generator for explaining a steady state operation in the lost tracking system of FIG.

3 is a block diagram illustrating an operation between a lost signal generator and a connection relay point for explaining the operation of a lost communication network in a lost state in the lost tracking system of FIG.

4 is a flowchart illustrating a lost position tracking method according to an embodiment of the present invention.

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

100: Mia tracking system 110: Mia signal generator

112: signal controller 114: signal generator

116: child device modem 120: network generator

122: guardian device modem 124: control unit

126: signal generator 130: connection relay point

130a: fixed station 130b: mobile station

132: lost signal transceiver 134: signal information detector

136: information transmitter 140: Mia tracking center

150: tracking team

Claims (12)

A network generator that acts as a coordinator of the ZigBee protocol and is carried by a guardian; A mia signal generator, which is a beacon device that acts as an end device of the Zigbee protocol and is carried by a ward; A connection relay point acting as a coordinator of the Zigbee protocol and forming a lost communication network with the lost signal generator when a lost child occurs; And A lost tracking center for storing and analyzing data transmitted from the access relay point; Including, The MIA signal generator configures a communication network with the network generator using a general wireless personal area network identifier (PANID), and automatically determines the wireless personal area network unique number for the lost signal when it is determined that the lost situation occurs. A lost tracking system that forms a communication network with the access relay point using Rescue PANID. The method of claim 1, The lost signal generator includes a signal control unit for increasing a transmission output and forming a communication network with the connection relay point when it is determined that the lost signal occurs. The method of claim 1, The network generator comprises a control unit for measuring the distance from the signal generator to the lost signal using the received signal when the communication with the lost signal generator is lost. The method of claim 1, The communication network generator is a lost tracking system including an alarm unit for notifying the guardian when the lost occurs. The method of claim 1, The connection relay point is a lost tracking system operable in the form of a fixed station or mobile station of the communication network. The method of claim 5, When the access point is operated in the form of a mobile station Mia tracking system is provided with an alarm unit for notifying the occurrence of the missing user to operate the access point. The method of claim 1, The access point is a lost tracking system for transmitting data to the lost tracking center using a communication network capable of data communication, including a mobile communication network, a wireless data communication network. Forming a communication network by a lost signal generator and a network generator using a general PANID of a Zigbee protocol; Determining whether a lost child occurs when communication between the lost signal generator and the network generator becomes incapable of communication; Automatically transmitting a lost network connection request signal to an access relay point using a Rescue PANID in the lost signal generator when it is determined that the lost situation occurs; Forming a lost communication network by receiving a connection relay point receiving the lost signal generator and the lost network connection request signal; Analyzing the MIA network request signal and collecting device information at the access relay point; Transmitting the collected device information to a child tracking center; And Storing and analyzing device information transmitted from the access relay point at the lost tracking center and tracking the location of the lost signal generator; Mia tracking system location tracking method comprising a. The method of claim 8, The lost signal generator transmits a device information signal and the communication network generator transmits a response signal to the device information signal. If the response signal is not received from the lost signal generator for a predetermined time, the location tracking method of the lost tracking system. The method of claim 8, The device information includes a unique number of the lost signal generator, the location tracking method of the lost track system including the time information of the transmission and reception of the device information signal. The method of claim 8, And the MIA signal generator establishes a communication network with the access relay point using the Rescue PANID for a preset time and attempts to recombine the communication network using the network generator and the general PANID. The method of claim 8, Position tracking of the lost signal generator, Receiving a MIA network request signal transmitted from one MIA signal generator at a plurality of access relay points with a time difference; And Calculating a moving path of the lost child based on a record of the position of the connected relay point where the lost communication network was formed at the plurality of connected relay points; Mia tracking system location tracking method comprising a.

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