KR20230075088A - Satellite communication system for observing polar environmental factors - Google Patents

Abstract

A satellite communication system is disclosed. The present system may include a coordinator terminal that communicates with a satellite and one or more end terminals that provide sensing data to the coordinator terminal. By providing the present system, it can be linked with an Internet-based system in polar regions and the system can be stably operated.

Description

Satellite communication system for observing polar environmental factors {SATELLITE COMMUNICATION SYSTEM FOR OBSERVING POLAR ENVIRONMENTAL FACTORS}

The present invention constructs a wireless sensor network (hereinafter referred to as 'WSN') in an area where Internet access is not smooth, such as in an extreme area, to observe and transmit environmental factors affecting climate change unattended for a long time without data loss. It is about a satellite communication system for

A satellite-based communication method can be applied in polar regions, deserts, and oceans where power and Internet-based communication infrastructure is not established, and a WSN that periodically collects various environmental factors can be configured.

The WSN may include various sensor nodes that collect environmental information affecting climate change and a sink node that is a satellite gateway that receives information from the sensor nodes and communicates with satellites.

However, defects may occur in the satellite gateway, which is a sink node, due to severe weather, natural disasters, etc., and the defect not only causes a large data loss, but also has a great impact on the operation of the entire system.

Accordingly, a method for operating the system more stably is required.

On the other hand, the above information is presented only as background information to help the understanding of the present invention. No determination has been made, nor is any assertion made, as to whether any of the foregoing is applicable as prior art with respect to the present invention.

Publication No. 10-2021-0133084 (Publication date: 2021.11.5.)

The present invention has been made to solve the above problems, and one problem to be solved by the present invention is to provide a satellite communication system that communicates with an Internet-based system in polar regions where power and Internet-based communication infrastructure is not established or insufficient. is in

Another object of the present invention is to provide a satellite communication system that supplies power based on natural forces (eg, wind power, sunlight, etc.) in an environment where power supply is poor.

Another object of the present invention is to provide a satellite communication system that duplicates the central node in preparation for battery discharge and defect occurrence of the central node of the WSN.

The technical problems to be achieved in the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art from the description below. You will be able to.

A satellite communication system according to an embodiment of the present invention may include a coordinator terminal communicating with a satellite and one or more end terminals providing sensing data to the coordinator terminal.

The coordinator terminal and the end terminal may each include a communication unit, a battery, a generator using natural force, and a controller for charging the battery using the generator.

Here, when the battery capacity of the coordinator terminal decreases below a predetermined value or an abnormal operation is detected, one of the end terminals may be changed to a coordinator terminal, and the coordinator terminal before the change may be changed to an end terminal.

The end terminal may collect environmental information related to at least one of temperature, humidity, wind direction, wind speed, precipitation, snowfall, underground temperature, fine dust, and harmful gas in an area where access to the Internet is difficult, and provide the collected information to the coordinator terminal.

The coordinator terminal that has collected the environment information may be configured to provide the collected environment information to a system within Internet range through the satellite.

In order to effectively use the battery, the end terminal may be configured to have a series of driving cycles in which it collects environmental factor information, transmits the collected environmental factor information to the coordinator terminal, and operates in a sleep mode for a predetermined period of time.

The coordinator terminal and the end terminal may be configured to perform short-range communication based on Zigbee or Long Range (LoRa) communication.

When a coordinator terminal and an end terminal configure a local area communication network for the first time, the coordinator terminal leaves the previously connected network, searches for a local area communication network, participates as a coordinator terminal if there is no searched local area communication network, and searches for a local area communication network. If there is a communication network, it may be configured to participate as an end terminal of the local area communication network.

The end terminal is configured to periodically transmit a request message for joining the local area communication network to the coordinator terminal, and to periodically transmit sensing data to the coordinator terminal when the coordinator terminal to which the request message is transmitted permits joining the local area communication network. It can be.

One end terminal among the end terminals is set as a spare coordinator terminal, and the spare coordinator terminal sends a coordinator terminal change request to the coordinator terminal when the usable battery capacity of the coordinator terminal is below a predetermined value or the satellite communication state is below a predetermined level. can be configured to transmit.

When the preliminary coordinator terminal does not receive the status response message of the coordinator terminal a predetermined number of times or for a predetermined period of time, it may configure a new local area communication network by leaving the existing local area communication network.

The preliminary coordinator terminal may be a terminal having the best battery capacity state or a terminal that first transmits a network subscription request message to the coordinator terminal.

The coordinator terminal may be configured to transmit a coordinator change request message to the preliminary coordinator terminal when it is determined through self-monitoring that the coordinator terminal needs to be changed.

By providing a satellite communication system according to various embodiments of the present invention, it can be interlocked with an Internet-based system in polar regions, etc., operational efficiency can be improved by supplying power using natural forces, and even if a problem occurs in the satellite gateway, master redundancy This allows the system to operate stably.

The effects obtainable in the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the description below. will be.

1 is a diagram for schematically explaining a satellite communication system according to an embodiment of the present invention;
2 is a diagram for explaining a network configuration of a satellite communication system according to an embodiment of the present invention;
3 is a block diagram showing the configuration of a coordinator terminal according to an embodiment of the present invention;
4 is a diagram showing a situation in which the roles of a coordinator terminal and an end terminal are changed according to an embodiment of the present invention;
5 is a sequence diagram for explaining a process of joining or configuring a network of a terminal according to an embodiment of the present invention;
6 is a sequence diagram for explaining a status message exchange process in a local area communication network according to an embodiment of the present invention, and
7 and 8 are sequence diagrams for explaining a duplication process of a coordinator terminal according to an embodiment of the present invention.

Advantages and features of the present invention, and methods of achieving them, will become clear with reference to the detailed description of the following embodiments taken in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, only these embodiments are intended to complete the disclosure of the present invention, and are common in the art to which the present invention belongs. It is provided to fully inform the person skilled in the art of the scope of the invention, and the invention is only defined by the scope of the claims.

Terminology used herein is for describing the embodiments and is not intended to limit the present invention. In this specification, singular forms also include plural forms unless specifically stated otherwise in a phrase. As used herein, "comprises" and/or "comprising" does not exclude the presence or addition of one or more other elements other than the recited elements. Like reference numerals throughout the specification refer to like elements, and “and/or” includes each and every combination of one or more of the recited elements. Although "first", "second", etc. are used to describe various components, these components are not limited by these terms, of course. These terms are only used to distinguish one component from another. Accordingly, it goes without saying that the first element mentioned below may also be the second element within the technical spirit of the present invention.

Unless otherwise defined, all terms (including technical and scientific terms) used in this specification may be used with meanings commonly understood by those skilled in the art to which the present invention belongs. In addition, terms defined in commonly used dictionaries are not interpreted ideally or excessively unless explicitly specifically defined.

The spatially relative terms "below", "beneath", "lower", "above", "upper", etc. It can be used to easily describe a component's correlation with other components. Spatially relative terms should be understood as including different orientations of elements in use or operation in addition to the orientations shown in the drawings. For example, if you flip a component that is shown in a drawing, a component described as "below" or "beneath" another component will be placed "above" the other component. can Thus, the exemplary term “below” may include directions of both below and above. Components may also be oriented in other orientations, and thus spatially relative terms may be interpreted according to orientation.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a diagram schematically illustrating a satellite communication system according to an embodiment of the present invention. 2 is a diagram for explaining a network configuration of a satellite communication system 1 according to an embodiment of the present invention.

The satellite communication system 1 is a system configured in the satellite communication environment 10, and the coordinator terminal (ZC) of the satellite communication system 1 periodically receives environmental data from a plurality of sensor nodes (ZSC) (ZSC1 to 4). can be collected and may include satellite gateways.

The coordinator terminal (ZC) can collect environmental data and transmit it to the artificial satellite (AS), and the artificial satellite (AS) can transmit the collected environmental data to the artificial satellite ground system (ASS). The artificial satellite terrestrial system (ASS) may transmit data to a mail server (MS) or various systems of the Internet environment 20 .

The data transmitted to the Internet environment 20 can be managed through a protocol bridge (PB), an integrated data management platform (DMP) including a database, data management server, HTTP server, etc., and is variously visualized for researchers, It can be provided to administrators and the like.

The satellite communication system 1 may configure a local area network, for example, the satellite communication system 1 may perform local area communication based on ZigBee communication and/or LoRa. However, in this specification, description will be made focusing on ZigBee communication. A ZigBee network may include one coordinator terminal (ZC), one or more router terminals, and end terminals.

The coordinator terminal (ZC) plays a role of coordinating the operation of the entire network and configuring the network, and has a relatively higher power requirement than other terminals, and a large-capacity battery may be applied to supply power with a battery. In addition, the coordinator terminal ZC may have a generator based on natural forces (for example, sunlight, solar heat, wind power, intellectual power, etc.) to save battery. Here, the generator may include a power generation related module for using its own power generation module or an external power generation module.

The coordinator terminal (ZC) is responsible for initially configuring a short-distance communication network, and may select a personal area network (PAN) identifier to be used in the network and a physical radio channel to be used by the network when configuring the network. In this case, the coordinator terminal ZC may be driven as a router terminal to perform a routing function.

A router terminal may be configured in a structure that minimizes energy cost of a path through which packets are exchanged, and an end terminal may be logically connected to a parent router and communicate only with the parent router.

Here, the end terminal has no routing function, so the power requirements are relatively low and the battery life is long. In addition, since it operates in a wakeup mode only when environmental information is collected and operates in a sleep mode at other times, standby power is minimized and battery life can be increased. In addition, when the end terminal is equipped with a generator based on natural force, it is possible to stably operate the terminal by charging the battery in the idle mode.

The end device is periodically driven in wakeup mode, checks messages to be transmitted to the parent router, the parent router buffers data to be transmitted to its end device, and transmits the buffered data upon receiving a poll request from the end device. there is.

3 shows a configuration of a coordinator terminal 100 according to an embodiment of the present invention.

As an optional embodiment, the configuration of the coordinator device 100 may be the same as that of a preliminary coordinator device or an end device. The reserve coordinator terminal is an end terminal and may be a terminal to replace the coordinator terminal 100 due to a functional defect of the coordinator terminal 100, message non-response, or battery discharge. The coordinator terminal 100 is driven as a primary system and the standby coordinator terminal is driven as a secondary system, so that dualization of the primary system can be performed, and thus the system can be stably operated.

The coordinator terminal 100 is a terminal that communicates with satellites and can communicate with one or more end terminals that provide sensing data. The coordinator terminal 100 may include a communication unit 110 , a power supply unit 120 , a memory 150 and a controller 190 . However, since the above configurations are not essential components of the coordinator terminal 100, the coordinator terminal 100 in this specification may include more or fewer configurations.

The communication unit 110 may include a satellite communication unit 111 and a short range communication unit 113 . The satellite communication unit 111 includes a communication module for communicating with an artificial satellite, and the short-range communication unit 113 may include a communication module such as ZigBee, LoRa, Wi-Fi, Bluetooth, and BLE.

The communication unit 110 may store the measurement value transmitted by the end device in the memory 150 (eg, non-volatile memory (ROM, microSD, flash memory)).

The communication unit 110 may transmit information about an operation mode, information about a battery charge state, information about a satellite connection state, and reception strength information of a low power communication module as messages.

The power supply unit 120 may include a wind power generation module 121 and/or a photovoltaic power generation module 123, a power variable unit 125, and a battery 127, which are generators using natural force.

Specifically, the wind power generation module 121 may be a module for using the energy as a power source when energy by wind power is generated by itself or from the outside, and the photovoltaic power generation module 123 generates energy using a solar panel. When generated, it may be a module for using the corresponding energy as a power source. The battery 127 may be charged using a generator using natural force.

The power variable unit 125 may be a module that varies input power into power used by the controller 190 or the communication unit 110, and the battery 127 may be a module that provides power to the coordinator terminal 100. there is.

4 is a diagram illustrating a situation in which roles of a coordinator device and an end device are changed according to an embodiment of the present invention.

The end terminal (100, ZSC1) collects environmental information related to at least one of temperature, humidity, wind direction, wind speed, precipitation, snowfall, underground temperature, fine dust, and harmful gases in an area where access to the Internet is difficult, and the coordinator terminal (100 , ZC).

At this time, the coordinator terminal (100, ZC) may provide the collected environment information to a system within the range of the Internet through a satellite.

In order to effectively use the battery, the end terminal (100, ZSC1) collects environmental factor information, transmits the collected environmental factor information to the coordinator terminal (100, ZC), and performs a series of driving cycles operating in sleep mode for a predetermined time. can have Accordingly, battery consumption of the end terminal 100 (ZSC1) can be efficiently managed.

The coordinator terminal 100 (ZC) and the end terminal 100 (ZSC1) may perform short-range communication based on Zigbee or LoRa (Long Range) communication.

When the battery capacity of the coordinator terminal (100, ZC) decreases below a predetermined value or an abnormal operation is detected, one of the end terminals (100, ZSC1) is changed to a coordinator terminal, and the coordinator terminal before the change may be changed to an end terminal. there is. In this case, a terminal that is changed to a coordinator terminal among end terminals may be a preliminary coordinator terminal, but the embodiment is not limited thereto.

5 is a sequence diagram illustrating a process of joining or configuring a network of a terminal according to an embodiment of the present invention, and the terminal may be a coordinator terminal or an end terminal.

First, the terminal is powered on (S510).

When the power is turned on or reset, the terminal leaves the existing local area communication network mapped to a predetermined PAN identifier and physical radio channel (S515).

After that, the terminal searches for a short-distance communication network (S520).

As an optional embodiment, a terminal may be implemented to wait for a predetermined time before finding a short-range communication network. When serving as a coordinator terminal, the battery state may not be good, so a predetermined waiting time for another terminal to become a coordinator terminal. can have

When a short-range communication network is found (S520), the terminal joins the short-range communication network (S525). In this case, the terminal becomes an end terminal and can join the local area communication network.

The corresponding end terminal is at wakeup time (S530), and if there is a message to be transmitted, it reports the status to the coordinator terminal (or parent router terminal) (S535). The message for reporting the status may include environment data, and may include identification information and status information of the corresponding end terminal.

The end terminal receives a status response from the coordinator terminal or router terminal of the existing local area communication network (S540), and if the message type is a switching request (S550), it enters the next step of the power-on phase (S510), and if it does not receive a status response (S540), it is retried, and at the time of retry, there is a status response (S545), and if the message type is a switching request (S550), it is possible to enter the next step of the power-on step (S510), and when retrying, the state If there is no response (S545), the status may be reported again (S535) and the status response may be waited (S540).

As an optional embodiment, the end terminal may be implemented to create a new short-range communication network when there is no status response repeatedly. In this case, the end device may be driven as a coordinator device.

Again, when the short-range communication network is not found (S520), the terminal configures a new short-range communication network (S555).

That is, when the terminal becomes a coordinator terminal and waits for reception (S560), the message type is a status report (S565), the message type is a message requesting switching (S575), delays (S580), and the existing short-range communication network leaves (S515).

As shown in Salpin, when the coordinator terminal and the end terminal initially configure a short-distance communication network, The coordinator terminal leaves the previously connected network, searches for a local area communication network, participates as a coordinator terminal if there is no searched local area communication network, and participates as an end terminal of the local area communication network if there is a searched local area communication network. can

The end terminal is configured to periodically transmit a request message for joining the local area communication network to the coordinator terminal, and to periodically transmit sensing data to the coordinator terminal when the coordinator terminal to which the request message is transmitted permits the local area communication network subscription. can

6 is a sequence diagram illustrating a status message exchange process in a local area communication network according to an embodiment of the present invention.

The preliminary coordinator device 100 (ZSC1) is a type of end device and may serve as a coordinator device when there is no coordinator device 100 (ZC).

The end terminal (100, ZSC2) transmits a short-distance communication network subscription request to the coordinator terminal (100, ZC) and the preliminary coordinator terminal (100, ZSC1) (S610).

Yet, the power of the coordinator device 100 (ZC) and the spare coordinator device 100 (ZSC1) has not been turned on, and the coordinator device 100 (ZC) and the spare coordinator device 100 (ZSC1) may also be a kind of end device, It may be set as a coordinator terminal and a preliminary coordinator terminal in advance.

The coordinator terminal 100 (ZC) turns on power (S615). The coordinator device 100 (ZC) attempts short-range communication with the preliminary coordinator device 100 (ZSC1) and the end device 100 (ZSC2) (S620).

The coordinator terminal (100, ZC) configures a new short-range communication network (S625) and receives a message for requesting the end terminal (100, ZSC2) to join the short-range communication network (S630). At this time, the preliminary coordinator terminal 100 (ZSC1) is in a state in which power is not yet turned on.

The power of the preliminary coordinator device 100 (ZSC1) is turned on (S635), and the coordinator device 100 (ZC) responds to the end device 100 (ZSC2) to the short-range communication network subscription request (S640).

The preliminary coordinator terminal (100, ZSC1) may request a short-range communication network subscription request to the coordinator terminal (100, ZC) and the end terminal (100, ZSC2) (S645). In this case, the coordinator terminal 100 (ZC) may respond to network subscription of the preliminary coordinator terminal 100 (ZSC1) (S650).

After the short-distance communication network is configured, the coordinator terminal 100 (ZC) periodically receives a status report message and a sensing data report message (S655 and S665). In response, the coordinator terminal (100, ZC) transmits a response message (S660, S670).

The coordinator terminal 100 (ZC) may transmit information on an operation mode, information on a battery charging state, information on a satellite connection state, and reception strength information of a low power communication module as a response message.

7 and 8 are sequence diagrams for explaining a duplication process of a coordinator terminal according to an embodiment of the present invention. Specifically, FIG. 7 is a preliminary coordinator terminal 100 (ZSC1) according to an embodiment of the present invention. It is a sequence diagram for explaining a process of directly requesting a role change from the coordinator terminal (100, ZC), and FIG. (100, ZSC1) is a sequence diagram to explain the process of configuring a direct network.

Referring to FIG. 7 , the coordinator device 100 (ZC) before the change receives a status report message from the preliminary coordinator device 100 (ZSC1) before the change (S710, S720), and transmits a status response message (S715, S725).

The coordinator terminal 100 (ZC) may transmit information on an operation mode, information on a battery charging state, information on a satellite connection state, and reception strength information of a low power communication module as a response message.

At this time, the preliminary coordinator terminal 100 (ZSC1) before the change may determine whether or not there is a system abnormality such as a battery status or a satellite status of the coordinator terminal 100 (ZC) based on the status response message. A switching request for changing a terminal may be determined.

Before the change, the preliminary coordinator terminal 100 (ZSC1) may request switching and receive a switching response (S735, S740).

In this case, both terminals (ZC, ZSC1) leave the existing local area communication network (S745, S750), and the coordinator terminal (100, ZC) before the change is changed to the spare coordinator terminal (100, ZC) after the change (S760). , The preliminary coordinator terminal 100 (ZSC1) before the change may be changed to the coordinator terminal 100 (ZC) after the change (S755).

After the change, the coordinator terminal configures a new short-range communication network (S765), receives a request from a preliminary coordinator terminal after changing the short-range communication network subscription request, and responds thereto (S765, S770).

Also, after the change, the coordinator terminal receives a status report message (S775) and transmits a status response message (S780).

As seen, one of the end terminals is set as a spare coordinator terminal, and the spare coordinator terminal is When the usable battery capacity of the coordinator terminal is less than or equal to a predetermined value or the satellite communication state is less than or equal to a predetermined level, a request for changing the coordinator terminal may be transmitted to the coordinator terminal.

In addition, when the preliminary coordinator terminal does not receive the status response message of the coordinator terminal a predetermined number of times or for a predetermined period of time, it may configure a new local area communication network by leaving the existing local area communication network.

In this case, the preliminary coordinator terminal may be a terminal having the best battery capacity state or a terminal that first transmits a network join request message to the coordinator terminal.

In addition, the coordinator terminal may be configured to transmit a coordinator change request message to a preliminary coordinator terminal when it is determined through self-monitoring that the coordinator terminal needs to be changed.

Referring to FIG. 8 , the pre-change coordinator device 100 (ZC) may receive a status report from the pre-change preliminary coordinator device 100 (ZSC1) and repeatedly transmit a status response message (S810 to S825).

If, despite the preliminary coordinator terminal (100, ZSC1) transmitting the status report message (S830), if it does not receive a status response (S840), it leaves the existing short-range communication network (S845) and configures a new short-range communication network. (S850), and may be changed to a coordinator terminal (S860).

On the other hand, implementations of functional operations and subjects described in this specification may be implemented as digital electronic circuits, implemented as computer software, firmware, or hardware including the structure disclosed in this specification and its structural equivalents, or one or more of these. can be implemented by combining Implementations of the subject matter described in this specification are one or more modules of computer program instructions encoded on a tangible program storage medium for execution by or for controlling the operation of one or more computer program products, i.e., control systems. can be implemented

A computer readable medium may be a machine readable storage device, a machine readable storage substrate, a memory device, a composition of matter that affects a machine readable propagating signal, or a combination of one or more of these.

The terms "system" or "apparatus" herein include all mechanisms, devices and machines for controlling data, including, for example, programmable processors, computers, or multiple processors or computers. A control system may include, in addition to hardware, code that forms an execution environment for computer programs on demand, such as, for example, code constituting processor firmware, a protocol stack, a database management system, an operating system, or a combination of one or more of these. .

A computer program (also known as a program, software, software application, script or code) may be written in any form of programming language, including compiled or interpreted language, a priori or procedural language, and may be a stand-alone program or module; It may be deployed in any form including components, subroutines, or other units suitable for use in a computer environment. A computer program does not necessarily correspond to a file in a file system. A program may be in a single file provided to the requested program, or in multiple interacting files (e.g., one or more modules, subprograms, or files that store portions of code), or parts of files that hold other programs or data. (eg, one or more scripts stored within a markup language document). A computer program may be deployed to be executed on a single computer or multiple computers located at one site or distributed across multiple sites and interconnected by a communication network.

On the other hand, computer-readable media suitable for storing computer program instructions and data include, for example, semiconductor memory devices such as EPROM, EEPROM and flash memory devices, magnetic disks such as internal hard disks or external disks, magneto-optical disks and CDs. - may include all forms of non-volatile memory, media and memory devices, including ROM and DVD-ROM disks. The processor and memory may be supplemented by, or incorporated into, special purpose logic circuitry.

Implementations of the subject matter described herein may include back-end components, such as, for example, data servers, or may include middleware components, such as, for example, application servers, or may include, for example, web browsers or graphical users through which users may interact with implementations of the subject matter described herein. It may also be implemented in a computing system that includes a front-end component, such as a client computer having an interface, or any combination of one or more of such back-ends, middleware, or front-end components. The components of the system are interconnectable by any form or medium of digital data communication, such as, for example, a communication network.

Although this specification contains many specific implementation details, they should not be construed as limiting on the scope of any invention or what is claimed, but rather as a description of features that may be unique to a particular embodiment of a particular invention. It should be understood. Likewise, certain features that are described in this specification in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments individually or in any suitable subcombination. Further, while features may operate in particular combinations and are initially depicted as such claimed, one or more features from a claimed combination may in some cases be excluded from that combination, and the claimed combination is a subcombination. or sub-combination variations.

In addition, although operations are depicted in the drawings in a specific order in this specification, it is not to be understood that such operations must be performed in the specific order shown or sequential order or that all illustrated operations must be performed in order to obtain desired results. Can not be done. In certain cases, multitasking and parallel processing can be advantageous. Further, the separation of various system components in the embodiments described above should not be understood as requiring such separation in all embodiments, and the program components and systems described may generally be integrated together into a single software product or packaged into multiple software products. It should be understood that you can

As such, this specification is not intended to limit the invention to the specific terms presented. Therefore, although the present invention has been described in detail with reference to the above-described examples, those skilled in the art may make alterations, changes, and modifications to the present examples without departing from the scope of the present invention. The scope of the present invention is indicated by the following claims rather than the detailed description above, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present invention. do.

Claims (10)

As a satellite communication system,
A coordinator terminal communicating with the satellite; and
Including one or more end terminals that provide sensing data to the coordinator terminal,
The coordinator terminal and the end terminal,
communications department; battery; Generators using natural power; And each includes a controller for charging the battery using the generator,
The satellite communication system, wherein, when the battery capacity of the coordinator terminal decreases below a predetermined value or an abnormal operation is detected, one of the end terminals is changed to a coordinator terminal, and the coordinator terminal before the change is changed to an end terminal. According to claim 1,
end terminal,
In areas where access to the Internet is difficult, environmental information related to at least one of temperature, humidity, wind direction, wind speed, precipitation, snowfall, underground temperature, fine dust and harmful gases is collected and provided to the coordinator terminal,
The coordinator terminal that collected the environment information,
A satellite communication system configured to provide the collected environmental information to a system within internet range via the satellite. According to claim 1,
end terminal,
A satellite communication system configured to have a series of driving cycles in which the battery is effectively used, collecting environmental factor information, transmitting the collected environmental factor information to a coordinator terminal, and operating in a sleep mode for a predetermined period of time. According to claim 1,
A satellite communication system in which the coordinator terminal and the end terminal are configured to perform short-range communication based on Zigbee or Long Range (LoRa) communication. According to claim 1,
When the coordinator terminal and the end terminal initially configure a short-distance communication network,
The coordinator terminal,
After leaving the previously connected network, search for a local area communication network, participate as a coordinator terminal if there is no searched local area communication network, and participate as an end terminal of the local area communication network if there is a searched local area communication network. , satellite communication system. According to claim 5,
end terminal,
Periodically transmits a request message for joining the local area communication network to the coordinator terminal,
The satellite communication system configured to periodically transmit sensing data to the coordinator terminal when the coordinator terminal to which the request message is transmitted permits joining the local area communication network. According to claim 6,
One of the end terminals is set as a preliminary coordinator terminal,
The preliminary coordinator terminal,
A satellite communication system configured to transmit a coordinator terminal change request to a coordinator terminal when the usable battery capacity of the coordinator terminal is less than or equal to a predetermined value or the satellite communication state is less than or equal to a predetermined level. According to claim 7,
The preliminary coordinator terminal,
A satellite communication system that configures a new local area communication network by leaving the existing local area communication network when the status response message of the coordinator terminal is not received a predetermined number of times or for a predetermined period of time. According to claim 8,
The preliminary coordinator terminal,
A satellite communication system, which is a terminal with the best battery capacity or a terminal that transmits a network subscription request message to a coordinator terminal for the first time. According to claim 8,
The coordinator terminal,
The satellite communication system configured to transmit a coordinator change request message to the preliminary coordinator terminal when it is determined through self-monitoring that a coordinator terminal needs to be changed.

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