Terminal operation control method in wireless distributed communication system

Abstract

To properly test the reliability of signals transmitted by terminals.SOLUTION: A method performed by a receiving terminal for authenticity checking of packets in a distributed communication system, includes the steps of: receiving, from a transmitting terminal, a packet containing identification information identifying a transmitting terminal or a receiving terminal and a public trust field; determining whether the public trust field has been generated based on receiving terminal identification information or transmitting terminal identification information; comparing the public trust field with a trust value stored in advance and corresponding to the identification information to verify the reliability of the packet; and verifying, by the receiving terminal, when the public trust field is based on the receiving terminal identification information, the reliability of the packet only when the identification information in the receiving packet is coincident with the identification information of the receiving terminal, and verifying, by the receiving terminal, when the public trust field is based on the identification information of the transmitting terminal, the reliability of the packet only when having authority information indicating reliability verification authority stored in advance.SELECTED DRAWING: Figure 19

Description

[Technical Field]

[0001] The present invention relates to a method for controlling a terminal in a wireless distributed communication system operating on a synchronous TDMA channel.

[0002] The present invention provides a novel wireless distributed communication system based on Reference 1 (Korean Patent Application No. 10-2017-0026778, Accession No. 1-1-2017-0207822-47, Collision avoidance method in a synchronous wireless communication system), Reference 2 (Korean Patent Application No. 10-2015-0187458, Accession No. 1-1-2015-1275581-10, Slot control and automatic repeat request method for SOTDMA in a specific application message channel), and Reference 3 (Korean Patent Application No. 10-2018-0014682, Accession No. 1-1-2018-0131792-95, Service method using multiple channels in a synchronous TDMA system), and relates to a terminal control method for actually realizing the system.

[0003] The present invention relates to a wireless distributed communication system for which no representative product has been widely commercialized internationally to date.

[0004] The present invention also relates to a method for setting addresses of terminals in a wireless distributed communication system, and more particularly to a method for setting addresses of mobile, fixed and indoor terminals in a wireless distributed communication system and a method for utilizing the set addresses.

[0005] The present invention also relates to a method for a wireless terminal to automatically recognize and communicate with an object in a wireless communication system, and more particularly to a method for allowing a user of a wireless terminal to easily receive services from an object.

[0006] The present invention also relates to a method for a wireless terminal to automatically recognize and communicate with an object in a wireless communication system, and more particularly to a method for allowing a user of a wireless terminal to easily receive services from an object.

[0007] The present invention relates to a method for performing one-to-many communication in a distributed communication system, and more particularly to a method for receiving ACK responses to a packet transmitted from one terminal to multiple terminals.

[0008] The present invention can be utilized to enable drones to perform one-to-many communication when flying in a swarm.

[0009] The present invention can be utilized when one terminal transmits a file to multiple terminals.

[0010] The present invention relates to a method for many-to-many communication in a distributed communication system.

[0011] The present invention relates to a method for allocating many-to-many communication resources and transmitting many-to-many packets using the allocated resources. [Background technology]

[0012] Currently, the main collision control methods used in wireless communication environments are scheduling and CSMA / CA (Carrier Sense Multiple Access / Collision Avoidance). Scheduling is primarily used by mobile communication base stations to efficiently allocate resources to terminals without collisions. CSMA / CA is used in asynchronous communication methods such as WiFi when multiple STAs compete for communication with an AP. Both methods are used in communication environments with a central control station.

[0013] On the other hand, in a wireless distributed communication environment, there is still no efficient collision avoidance method for large-scale connections. In particular, collision avoidance in a communication environment targeting a large number of mobile terminals, rather than a large number of fixed terminals, is extremely difficult.

[0014] Wireless distributed systems, which require large-scale connections, can only be commercialized if they are capable of collision avoidance. In wireless distributed systems, scheduling by a control station is sometimes impossible because there is no control station. CSMA / CA is used asynchronously, so synchronous methods may not be appropriate. In particular, WiFi using CSMA / CA is difficult for more than 50 people to use simultaneously. WiFi APs are typically installed in offices with an expected capacity of around 20-25 people.

[0015] This has created a demand for the development of technology that can efficiently avoid collisions in a synchronous wireless distributed communication environment that requires large-scale connections involving thousands or tens of thousands of people. Summary of the Invention [Problem to be solved by the invention]

[0016] The technical problem to be solved by the present invention is to provide a method for a wireless distributed terminal to determine communication parameters according to the situation in order to smoothly provide commercial wireless distributed communication services.

[0017] Another object of the present invention is to provide a method for a terminal to efficiently set an address in a wireless distributed communication system.

[0018] Another object of the present invention is to provide a method for providing a service based on a set address in a wireless distributed communication system.

[0019] Another object of the present invention is to provide a method for a terminal to automatically recognize an object and immediately communicate with the object.

[0020] Another object of the present invention is to provide things that the user terminal can recognize and control.

[0021] Another object of the present invention is to provide a method for incorporating drivers and programs into things and downloading them wirelessly from the things.

[0022] The present invention also aims to provide a way to make things work with low power using tone channel and tone slot patterns.

[0023] Another object of the present invention is to provide a method for updating drivers and programs built into things.

[0024] SUMMARY OF THE INVENTION An object of the present invention is to provide a method for performing point-to-multipoint communication in a synchronous wireless distributed communication system.

[0025] Another object of the present invention is to provide a method for utilizing one-to-many communication for swarm drone communication, vehicle-to-vehicle communication, and wireless transmission of group files.

[0026] An object of the present invention is to provide a method for transmitting an ACK response in point-to-multipoint communication.

[0027] An object of the present invention is to provide a highly reliable communication and file transfer method in one-to-many communication.

[0028] SUMMARY OF THE INVENTION An object of the present invention is to provide a method for performing many-to-many communication in a synchronous wireless distributed communication system.

[0029] The present invention also aims to provide a method applicable to fields such as swarm drone communication, vehicle-to-vehicle communication, and wireless group chat via many-to-many communication.

[0030] Another object of the present invention is to provide a method for dynamically allocating resources and transmitting many-to-many packets.

[0031] Another object of the present invention is to provide a method for stably performing wireless many-to-many communication even in the case of mobile terminals. [Means for solving the problem]

[0032] According to an embodiment of the present invention, a method for a distributed terminal to determine distributed communication parameters in a wireless distributed communication system may be provided, wherein the method for a distributed terminal to determine distributed communication parameters may include the steps of generating at least one communication parameter file including distributed communication parameters, storing the generated at least one communication parameter file in the distributed terminal, setting communication parameters in the distributed terminal based on the stored communication parameter file, and updating the stored communication parameter file in the distributed terminal periodically or at a specified time.

[0033] According to one embodiment of the present invention, a method for setting an address for wireless distributed communication in an integrated terminal equipped with a wireless distributed communication modem in a wireless distributed communication system can include a step of setting the address of the wireless distributed terminal using the telephone number of the mobile terminal.

[0034] According to an embodiment of the present invention, a method for a terminal to automatically recognize and control an object may be provided, in which the method for a terminal to automatically recognize and control an object may include the steps of: storing a file for recognizing and controlling the object; downloading the stored file from the object by the terminal via wireless communication; and recognizing the object by the terminal using the downloaded file.

[0035] According to one embodiment of the present invention, a point-to-multipoint communication method for performing an ACK response in a wireless distributed communication system may include the steps of: a terminal allocating use slot resources for point-to-multipoint communication using a contention proxy channel; a terminal transmitting point-to-multipoint communication packets to multiple other terminals using the allocated use slot resources; a multiple terminal receiving the point-to-multipoint packets; each terminal receiving the point-to-multipoint packets transmitting an ACK response for the point-to-multipoint packet; and a terminal that transmitted the point-to-multipoint packet receiving the ACK response.

[0036] According to an embodiment of the present invention, a method for performing many-to-many communication by a terminal in a wireless distributed communication system may be provided, which may include allocating slot resources for the many-to-many communication, allocating one of the allocated many-to-many slots using a contention proxy channel having a different frequency when the terminal transmits a many-to-many packet, and transmitting the many-to-many communication packet using the allocated slot resource. [Effects of the Invention]

[0037] According to the present invention, a method for controlling a distributed terminal in order to provide various services via the distributed terminal in a distributed communication system can be provided.

[0038] According to the present invention, it is possible to provide a method for efficiently setting addresses to terminals in a wireless distributed communication system.

[0039] The present invention can provide services based on addresses set in a wireless distributed communication system.

[0040] According to the present invention, the terminal automatically recognizes an object and performs communication, so that services for the object can be provided quickly and easily.

[0041] According to the present invention, one-to-many communication can be performed in a synchronous wireless distributed communication system.

[0042] According to the present invention, one-to-many communication can be utilized for communication between drone swarms, vehicle-to-vehicle communication, and wireless transmission of group files.

[0043] According to the present invention, an ACK response can be transmitted in one-to-many communication.

[0044] According to the present invention, highly reliable communication and file transfer can be performed in one-to-many communication.

[0045] According to the present invention, many-to-many communication can be performed in a synchronous wireless distributed communication system.

[0046] According to the present invention, it can be applied to fields such as communication between drones in a swarm, communication between vehicles, and wireless group chat through many-to-many communication.

[0047] According to the present invention, resources can be dynamically allocated and many-to-many packets can be transmitted.

[0048] According to the present invention, wireless many-to-many communication can be performed stably even in the case of mobile terminals.

[0049] The effects obtained by the present invention are not limited to those described above, and other effects not described above will be clearly understood by those having ordinary skill in the art to which the present invention pertains from the following description. [Brief explanation of the drawings]

[0050] [Figure 1] FIG. 2 is a diagram illustrating channels and slots. [Figure 2] FIG. 1 illustrates a traffic light service. [Figure 3] FIG. 10 is a diagram illustrating variables for determining distributed communication parameters. [Figure 4] FIG. 10 is a diagram showing the validity dates of the internal communication parameter file that is periodically updated. [Figure 5] FIG. 1 illustrates a method for allocating multiple fixed broadcast slots. [Figure 6a] A diagram showing a method in which a fixed distributed terminal updates an internal communication parameter file via a mobile distributed terminal. [Figure 6b] A diagram showing a method in which a fixed distributed terminal updates an internal communication parameter file via a mobile distributed terminal. [Figure 7a] A diagram showing a method in which a fixed distributed terminal updates an internal communication parameter file via a mobile distributed terminal. [Figure 7b]A diagram showing a method in which a fixed distributed terminal updates an internal communication parameter file via a mobile distributed terminal. [Figure 8] A diagram showing a method in which a mobile distributed terminal updates an internal communication parameter file via a fixed distributed terminal. [Figure 9a] A diagram showing a method in which a fixed distributed terminal provides a communication parameter file to a mobile distributed terminal via contention. [Figure 9b] A diagram showing a method in which a fixed distributed terminal provides a communication parameter file to a mobile distributed terminal via contention. [Figure 10a] A diagram showing a method in which a fixed distributed terminal provides a communication parameter file to a mobile distributed terminal via wired communication negotiation. [Figure 10b] A diagram showing a method in which a fixed distributed terminal provides a communication parameter file to a mobile distributed terminal via wired communication negotiation. [Figure 11] A diagram showing a method for configuring multiple built-in communication parameter files for wireless distributed terminals. [Figure 12] FIG. 1 illustrates a method for configuring an active parameter set for use by a distributed modem from multiple internal communication parameter files. [Figure 13] FIG. 1 illustrates various address configurations. [Figure 14] FIG. 10 is a diagram illustrating a method for an integrated terminal equipped with a wireless distributed modem to receive information. [Figure 15] FIG. 10 is a diagram illustrating a method of utilizing an integrated terminal equipped with a wireless distributed modem for ship communications in a wireless distributed system. [Figure 16a] A diagram showing how a mobile distributed terminal calculates its own location using the address of a fixed distributed terminal. [Figure 16b] A diagram showing how a mobile distributed terminal calculates its own location using the address of a fixed distributed terminal. [Figure 17] 10 is a diagram illustrating a method for requesting status information from various types of wireless distributed terminals present in a home. [Figure 18] FIG. 1 is a diagram showing the structure of a public trust packet proposed in the present invention. [Figure 19] FIG. 10 is a diagram illustrating a configuration for checking the reliability of a public trusted packet transmitted by a vehicle in wireless distributed communication. [Figure 20] 1 is a flowchart showing a comparison between a conventional method and the proposed method for recognizing objects. [Figure 21] FIG. 1 is a diagram illustrating the configuration of a device for automatically recognizing things. [Figure 22] 1 is a flowchart showing how a terminal directly downloads a driver or program from an object to recognize and control it. [Figure 23] This is a flowchart showing how a terminal awakens and recognizes sleeping objects. [Figure 24] FIG. 10 illustrates how a terminal uses a tone slot pattern to awaken sleeping entities. [Figure 25] This is a flowchart for selecting things to be automatically controlled by a program. [Figure 26] 1 is a flow chart of a method for granting control to an entity receiving a control signal. [Figure 27] 1 is a flowchart showing how a user terminal searches for and controls things that it has already recognized. [Figure 28] 10 is a flowchart showing how a user terminal updates files for recognition and control built into things. [Figure 29] 1 is a flowchart comparing the conventional thing recognition control steps experienced from the user's perspective with the thing recognition steps when the present invention is applied. [Figure 30] 1A and 1B are diagrams showing the configuration of a main channel and a sub-channel, and the configuration of a frame and a slot. [Figure 31] This is a diagram showing four drones heading towards the same point. [Figure 32] FIG. 10 is a diagram illustrating the configuration of a point-to-multipoint packet. [Figure 33] FIG. 10 is a diagram showing a method for performing an ACK response to a one-to-many packet proposed by the present invention. [Figure 34a]FIG. 10 is a diagram illustrating a method for transmitting an ACK response for one-to-many communication in a broadcast slot occupied by each terminal. [Figure 34b] FIG. 10 is a diagram illustrating a method for transmitting an ACK response for one-to-many communication in a broadcast slot occupied by each terminal. [Figure 35a] 10 is a diagram illustrating a method in which a terminal transmits an ACK response to a point-to-multipoint packet by transmitting a tone signal in a sub-slot of a contention tone slot resource. [Figure 35b] 10 is a diagram illustrating a method in which a terminal transmits an ACK response to a point-to-multipoint packet by transmitting a tone signal in a sub-slot of a contention tone slot resource. [Figure 35c] 10 is a diagram illustrating a method in which a terminal transmits an ACK response to a point-to-multipoint packet by transmitting a tone signal in a sub-slot of a contention tone slot resource. [Figure 35d] 10 is a diagram illustrating a method in which a terminal transmits an ACK response to a point-to-multipoint packet by transmitting a tone signal in a sub-slot of a contention tone slot resource. [Figure 35e] 10 is a diagram illustrating a method in which a terminal transmits an ACK response to a point-to-multipoint packet by transmitting a tone signal in a sub-slot of a contention tone slot resource. [Figure 35f] 10 is a diagram illustrating a method in which a terminal transmits an ACK response to a point-to-multipoint packet by transmitting a tone signal in a sub-slot of a contention tone slot resource. [Figure 36] FIG. 10 is a diagram illustrating a case where slot resources allocated for one-to-many communication collide. [Figure 37] 1 illustrates a method for transmitting group tones to detect resource collisions. [Figure 38] FIG. 10 is a diagram showing a method for receiving a slot map from each terminal and creating a group valid slot map. [Figure 39] FIG. 10 is a diagram illustrating a method for retransmission when a point-to-multipoint packet transmitting terminal does not receive an ACK. [Figure 40]FIG. 10 is a diagram illustrating a method in which a terminal performs communication taking into account the boundaries of a group communication area. [Figure 41] FIG. 10 illustrates a method for a terminal to dynamically join a one-to-many group. [Figure 42] FIG. 1 is a diagram showing the configuration of a main channel and a sub-channel, a frame, and a slot. [Figure 43] This figure shows a situation where four drones are moving towards the same point. [Figure 44] FIG. 1 illustrates a method for performing many-to-many communication. [Figure 45] FIG. 10 is a diagram showing a group valid slot map. [Figure 46] FIG. 10 is a diagram illustrating a method for performing group slot clearing when transmitting many-to-many packets. [Figure 47] FIG. 1 illustrates a method for constructing a point-to-multipoint packet. [Figure 48] FIG. 10 illustrates how each drone transmits response data in a broadcast slot when a many-to-many packet is sent in a used slot. [Figure 49] FIG. 10 illustrates a method for transmitting a many-to-many packet requesting a conditional response. [Figure 50] FIG. 10 is a diagram illustrating a method for responding to a many-to-many packet with a response condition. [Figure 51] FIG. 2 illustrates how a terminal dynamically joins a many-to-many communication group. [Figure 52] 10 illustrates a method for using group tone periods and group tones to check many-to-many slot resource collisions in real time. [Figure 53] FIG. 10 illustrates a many-to-many packet containing sequence information. [Figure 54a] 10A and 10B are diagrams illustrating a packet management method when a sequence error occurs in a many-to-many packet to be transmitted and received. [Figure 54b] 10A and 10B are diagrams illustrating a packet management method when a sequence error occurs in a many-to-many packet to be transmitted and received. [Figure 54c]10A and 10B are diagrams illustrating a packet management method when a sequence error occurs in a many-to-many packet to be transmitted and received. [Figure 54d] 10A and 10B are diagrams illustrating a packet management method when a sequence error occurs in a many-to-many packet to be transmitted and received. [Figure 54e] 10A and 10B are diagrams illustrating a packet management method when a sequence error occurs in a many-to-many packet to be transmitted and received. [Figure 54f] 10A and 10B are diagrams illustrating a packet management method when a sequence error occurs in a many-to-many packet to be transmitted and received. [Figure 55] 10A and 10B are diagrams illustrating a method for transmitting a packet informing the current sequence number when a terminal having a sequence error transmits a many-to-many packet including an incorrect sequence number. [Figure 56a] FIG. 10 is a diagram illustrating a method for performing retransmission by transmitting ACK and NACK for a many-to-many packet as tone signals. [Figure 56b] FIG. 10 is a diagram illustrating a method for performing retransmission by transmitting ACK and NACK for a many-to-many packet as tone signals. [Figure 57] 10 is a diagram illustrating a method for performing retransmission using the current sequence number broadcast when the current sequence number is broadcast in a many-to-many group information broadcast slot. [Figure 58] FIG. 10 is a diagram illustrating a method for a terminal to withdraw itself from a many-to-many group. [Figure 59] 1 is a diagram showing the configuration of an apparatus according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0051] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the drawings. In the following description and the accompanying drawings, substantially identical components are designated by the same reference numerals, and redundant description will be omitted. Furthermore, when describing the present invention, if it is determined that a detailed description of related well-known functions or configurations may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted.

[0052] In describing the embodiments of the present invention, if it is determined that a detailed description of a known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted. In addition, in the drawings, parts that are not related to the description of the present invention will be omitted, and similar parts will be designated by similar reference numerals.

[0053] In the present invention, when a component is "coupled," "coupled," or "connected" to another component, this includes not only a direct connection, but also an indirect connection where another component is interposed between them. Furthermore, when a component is described as "including" or "having" another component, this does not mean that the other component is excluded, but that the component can further include another component, unless otherwise specified.

[0054] In the present invention, terms such as "first" and "second" are used only to distinguish one component from another component, and do not limit the order or importance of the components unless otherwise specified. Therefore, within the scope of the present disclosure, a first component in one embodiment may be referred to as a second component in another embodiment, and similarly, a second component in one embodiment may be referred to as a first component in another embodiment.

[0055] In the present invention, components that are distinguished from one another are used to clearly describe the respective features and do not necessarily mean that the components are separate. In other words, multiple components may be integrated into a single hardware or software unit, or a single component may be distributed into multiple hardware or software units. Therefore, unless otherwise specified, such integrated or distributed embodiments are also included within the scope of the present invention.

[0056] In the present invention, the components described in the various embodiments are not necessarily essential components, and some of them are optional components. Therefore, an embodiment consisting of a subset of the components described in one embodiment is also included in the scope of the present disclosure. Furthermore, an embodiment including other components in addition to the components described in the various embodiments is also included in the scope of the present invention.

[0057] In relation to the present invention, conventional CSMA / CA can only be used in asynchronous communication systems. However, the wireless distributed communication system of the present invention can use a contention proxy channel so that CSMA / CA can also be used in synchronous systems. For example, a main channel and a sub-channel can be paired. The original data channel can have a broadband bandwidth of several MHz. In this case, the main communication band can be used as the data channel as is. The contention channel uses a narrowband signal. A frequency tone can be used as the narrowband signal, and since the frequency tone has a bandwidth of several kHz to several tens of kHz, it has a bandwidth of less than 1 / 100 of the broadband bandwidth. For example, if a 1 MHz band is composed of a 10 kHz tone channel and a 990 kHz data channel, the maximum data channel utilization rate is 99% under the assumption of no collisions. This is significantly more advantageous than the maximum channel utilization rate of 50% when CSMA / CA is used in the same band. In this case, for example, the sub-channel can be allocated immediately adjacent to the main channel. Also, as an example, the sub-channels may be allocated apart from the main channel, and are not limited to the above-described embodiment.

[0058] That is, in an environment where multiple (e.g., thousands or tens of thousands) terminals coexist, frequency efficiency can be improved by setting the channel on which multiple terminals contend to be different from the data transmission channel.

[0059] As an example, a terminal may perform pre-contention in a slot preceding a slot to be used. Specifically, if terminal A decides to use slot s of the main channel, terminal A may perform pre-contention in slot s-1, which is a contention substitute channel. In this case, terminal A may perform carrier sensing up to the subslot preceding the selected subslot, where N is the subslot number within the slot of the contention substitute channel. If no signal is detected as a result, terminal A transmits a contention tone signal from the selected subslot to the last subslot and transmits data in slot s of the main channel. In this case, as an example, if a signal is detected as a result of terminal A's performance, terminal A may determine that it has lost the contention and may not transmit any signal on the tone channel or main channel. However, the above-described subslot allocation is merely one embodiment and is not limited to a specific number. In other words, a terminal allocated the lowest number of subslots may transmit a contention signal after carrier sensing and transmit data on the main channel.

[0060] As an example, the signal of such a contention substitute channel can use a frequency tone signal. In this case, the frequency band can be used minimally. Hereinafter, the contention signal is assumed to be a tone signal. However, the contention signal can be set differently and is not limited to the above embodiment. Through the above contention, terminals that select the same slot can avoid collision. As an example, in the above situation, terminals that select the same slot from 500 can again avoid collision.

[0061] In the present invention, slot clearing may refer to the operation of transmitting a contention signal from sub-slot 0 in the previous slot s-1 of the contention proxy channel to prevent a neighboring terminal from attempting to use the slot s so that the terminal can continuously use the slot s without collision. That is, it may refer to the operation described above, and the following description will be based on this assumption.

[0062] Furthermore, as an example, the present invention describes a method for providing various services to distributed terminals in a distributed communication system based on the above and References 1 to 3. As an example, the distributed communication system may be a system in which terminals operate independently according to the situation without a control station for controlling the distributed communication, as described above. Therefore, communication parameters for controlling the distributed terminals in the distributed communication system may be required. As an example, most communication parameters in conventional communication systems may be implemented using hardware. That is, parameters in conventional communication systems may be fixed. As an example, a method for dynamically changing communication parameters, related to dynamic parameters, may be a method of transmitting a command to use the corresponding communication parameters via broadcast. As an example, an AIS (automatic identification system) terminal installed on a ship may determine its own frequency channel after first receiving DSC channel information. That is, while operating parameters can be changed as described above, the method of dynamically changing communication parameters is applicable only to the very limited extent of changing frequency channels.

[0063] Meanwhile, for example, in a wireless distributed communication system, parameters can be dynamically changed. Specifically, using fixed parameters in a wireless distributed communication system may make it difficult to provide various services. Therefore, it is necessary to dynamically change parameters in consideration of various services in a wireless distributed communication system. For example, conventional communication parameter change may mean setting limited communication parameters, such as frequency, transmission power, or designated slot information, differently for each country. Therefore, parameters different for each country may be stored in advance and then changed in the corresponding country.

[0064] However, when various services are provided through the wireless distributed communication system of the present invention, it can operate differently from conventional communication systems. Specifically, conventional wireless distributed communication does not require collision contention for communication resources, and wireless data stability may not be guaranteed due to collision of communication resources. Therefore, commercial services are rarely provided. In contrast, the present invention, based on the above and References 1 to 3, can consider providing services in an environment where collisions are detected and data stability is ensured, and in a situation where various commercial services are possible in this environment. In this case, for various services, multiple communication parameters need to be modified taking into account the characteristics of each service. Furthermore, communication parameters can be set differently for terminals that use specific services and terminals that do not. In other words, distributed terminals in a wireless distributed communication system can set different communication parameters according to their respective situations and operate based on these parameters.

[0065] In this case, there may be many communication parameters required for controlling the terminal. For example, based on the above, the contention channel and the channel transmitting actual data may be separate channels having different center frequencies. Therefore, communication parameters for the frequencies and mapping relationship of the two channels may be required. Also, for example, based on the above, communication parameters for slot clearing, ACK clearing techniques, and priority setting may be required. In addition, communication parameters for the slot configuration and channel configuration described in Reference 3 may also be required. For example, slot configurations include broadcast slots and reserved slots, and channel configurations include broadcast channels, reserved channels, and mixed channels. Broadcast slots are divided into designated broadcast slots, fixed broadcast slots, and general broadcast slots, and reserved slots are also divided into designated reserved slots, fixed reserved slots, and general reserved slots. In this case, a broadcast channel is a channel consisting of broadcast slots, a reserved channel is a channel consisting of reserved slots, and a mixed channel is a channel in which broadcast slots and reserved slots are mixed. In this case, communication parameters for the above slots may be required. The above parameters may be parameters that do not exist in conventional communication systems. For example, in the present invention, a plurality of slots and channels can be combined and operated to provide various services through a wireless distributed communication system, thereby providing various services to users in the wireless distributed communication system.

[0066] In addition, in conventional communication systems, most communication parameters are predefined, so that terminals can operate based on fixed rules, as described above. In other words, conventional communication systems cannot provide a variety of services. For example, when various services are to be provided through a system, it is necessary to be able to provide many services smoothly and immediately, and for this purpose, communication parameters need to be changed as needed. In consideration of the above, a method for determining communication parameters for controlling distributed terminals in a wireless distributed communication system will be described below.

[0067] Meanwhile, the above-mentioned wireless distributed communication system may basically be a wireless distributed communication system using synchronous TDMA. In this case, the communication resource in synchronous TDMA is a slot. For example, one frame is one second, and there may be 500 slot resources in one second.

[0068] Furthermore, the operation of distributed terminals can be controlled in a wireless distributed communication system. As described above, since a wireless distributed system does not have a base station for controlling distributed terminals, each distributed terminal must be controlled from a built-in communication parameter file. For example, communication parameters may vary by country or region, or may have different parameters depending on the contract or application. For example, communication parameters may vary depending on the service provided. Communication parameters may also be set differently depending on other factors, and are not limited to the above-described embodiment. In other words, since parameters in a wireless distributed system are highly dynamic, terminals must periodically update their communication parameter files for coordinated operation. For example, distributed terminals such as smart devices can be updated automatically. However, distributed terminals that are not connected to the Internet can mainly be updated via the smart device. For example, distributed road units in fixed terminals can connect to the Internet via a central control station, facilitating vehicle updates. In this case, since it is difficult for the vehicle to encrypt its own information, it can use a public trust packet disclosed in Reference 4 (Korean Patent Application No. 10-2018-0021102, Accession No. 1-1-2018-0187213-27, Method for Setting and Utilizing a Terminal Address in a Wireless Distributed Communication System). The built-in communication parameter file may be very large in size because it contains a large number of parameters and can be configured in a variety of ways. Therefore, it can be configured from multiple files. Each file has a priority, and the active parameter set can be managed in a structure in which a file with a higher priority is overwritten. The built-in communication parameter file may be at least one of a basic parameter file, a location type parameter file according to a location type, a contract parameter file according to a contract, a service parameter file according to service characteristics, a divided area parameter file that maps the location to a divided area and records related parameters, and a parameter conversion file for reducing the file size, and is not limited to the above-described embodiment. The above-described parameters will be described in detail below.

[0069] Also, as an example, a wireless distributed communication system may operate based on a slot resource allocation scheme. Based on the above and Reference 1, the wireless distributed communication system, unlike conventional technologies, can allocate slot resources via collision contention. Therefore, the probability of collisions occurring between distributed terminals in the wireless distributed communication system is extremely low, making it possible to support thousands or tens of thousands of connections. As an example, in a WiFi system, when 50 terminals simultaneously attempt resource allocation, the resource collision probability may be approximately 20%. In contrast, based on the above, even if 50,000 terminals simultaneously attempt resource allocation in the wireless distributed communication system, the collision probability is low, at approximately 2%. Also, as an example, the above-mentioned wireless distributed communication system may refer to a synchronous TDMA distributed communication system using a channel allocation scheme. Furthermore, in the wireless distributed communication system, slot allocation by distributed terminals via contention may be performed based on the above-mentioned contention proxy channel. Furthermore, the slot clearing, ACK clearing, and priority setting methods described in Reference 1 may be applied and are not limited to the above-mentioned embodiment.

[0070] For example, referring to FIG. 1, the slot configuration may include broadcast slots and usage slots, and the channel configuration may include broadcast channels, usage channels, and mixed channels. In this case, the broadcast slots are divided into designated broadcast slots, fixed broadcast slots, and general broadcast slots. The usage slots are also divided into designated usage slots, fixed usage slots, and general usage slots. The broadcast channel may be a channel consisting of broadcast slots, and the usage channel may be a channel consisting of usage slots. The mixed channel is a channel in which broadcast slots and usage slots are mixed.

[0071] As an example, a distributed modem for a wireless distributed communication system may refer to a modem used for modulating and demodulating signals. Also, as an example, hereinafter, a terminal may refer to a distributed terminal equipped with a distributed modem. However, this is for convenience of explanation only and is not limited to the above-described embodiment. Furthermore, when a distributed modem is equipped in a smart device, it may be referred to as a "smart device distributed terminal" or an "integrated terminal." However, without being limited to the above-described embodiment, different names may be used for terminals performing the same function. Meanwhile, as described above, a frame is 1 second and may be composed of 500 slots. Also, as an example, one slot may be composed of 56 subslots. In this case, the slot allocation method described below may take into account the above-described Reference 2. More specifically, when a first terminal allocates one slot to transmit information to a second terminal, the second terminal may also send a response using the slot allocated by the first terminal.

[0072] In this case, as an example, the wireless distributed communication system can operate based on the above, but it can be designed in various other ways, and distributed communication systems with other structures are also possible, and are not limited to the above-mentioned embodiments.

[0073] Next, a method for determining communication parameters of a terminal in a wireless distributed communication system will be described. As an example, in a wireless distributed communication system, as described above, there is no base station that controls distributed terminals. Therefore, a control means to replace the base station may be required. Furthermore, since distributed communication is a regional communication with a limited communication distance, communication parameters that reflect the characteristics of each region may be required for each region. As another example, communication parameters can be set differently for each service.

[0074] In this case, for example, the distributed terminals may have built-in communication parameters for their respective operations. In this case, the built-in communication parameter file may be updated periodically or within a specified period. In the following, for example, the parameters built into the distributed terminals as described above will be referred to as a "built-in communication parameter file." However, this is merely for convenience of explanation, and other names may be used for parameters performing the same operation, and the present invention is not limited to the above embodiment. In this case, for example, if the built-in communication parameter file is not updated, new services cannot be provided in the wireless distributed communication system.

[0075] As an example, referring to FIG. 2(a), a case can be considered in which a signal light information service is newly provided in slot number 0 of a broadcast channel. In this case, the newly provided signal light service may be a service that is newly provided from a specific time point. That is, it may be a service that has not been provided previously but is newly applied. In this case, as an example, the wireless distributed communication system (or wireless distributed communication operating system) needs to include information that the signal light service will be provided in slot number 0 of the broadcast channel in the communication parameter file. That is, it needs to add parameters for information required in consideration of the new service. In addition, all wireless distributed terminals in the wireless distributed communication system need to update the new communication parameter file periodically or within a specified time. As an example, the update may be performed before the specific time point described above.

[0076] Referring to FIG. 2(a), if terminal D has not updated its communication parameters before the specific time point described above, terminal D will not be able to confirm that slot 0 has been assigned to the signal light service. That is, terminal D may assign slot 0 for other purposes. Meanwhile, terminals A, B, and C, which are other distributed terminals located around terminal D, which has assigned slot 0, can use slot 0 for the signal light service. However, because the signal transmitted by terminal D in slot 0 acts as interference, terminals A, B, and C cannot properly receive the signal light information. For example, if the distributed terminal is a vehicle, the above-described situation may pose a safety risk. That is, it may pose a significant risk to people's safety. Therefore, taking the above-described situation into consideration, communication parameters may be updated periodically or at a fixed time interval, and the present invention is not limited to the above-described embodiment.

[0077] As another example, the wireless distributed communication system may have different parameter values ​​depending on the region, service, or type of terminal of the distributed communication. For example, a first region may broadcast signal light information on broadcast channel "0," while a second region may broadcast signal light information on channel "1" as shown in FIG. 2(b). Furthermore, as shown in FIG. 2(c), a third region may broadcast signal light information on channel "2." In other words, different parameter values ​​may be set for each region. For example, the transmission power of the signal light signal in the first region may be set to 25 dBm, the transmission power of the signal light signal in the second region may be set to 28 dBm, and the transmission power of the signal light signal in the third region may be set to 30 dBm. As another example, the transmission power of the signal light signal for a specific region within the first region may be set to 26 dBm and for another region may be set to 29 dBm. In other words, different values ​​may be set for specific regions within the same region. Therefore, communication parameters may also be set taking into account each region or a specific region within the region.

[0078] As another example, communication parameters may be set differently depending on the characteristics of the distributed terminal. For example, when the distributed terminal is a vehicle (i.e., when the distributed modem is installed in the vehicle), the communication parameters may be different from those when the distributed terminal is a smart device (i.e., when the distributed modem is installed in the smart device). Also, for example, when the distributed terminal is installed in a specific location as a fixed position, or when it is installed in a home appliance as a fixed position, the communication parameters may be set differently. The distributed terminals use the same communication method, but may perform different operations depending on the purpose for which they are installed and used. Therefore, the number and types of communication parameters may differ. Furthermore, the same parameters may have different values ​​depending on the characteristics, and are not limited to the above-described embodiments.

[0079] As another example, referring to Figure 3, communication parameters may be set differently depending on the user or operator of the wireless distributed communication system. For example, communication parameters may also vary depending on the contract between the distributed communication carrier and a commercial company.

[0080] Also, as an example, in the above-mentioned case, even if the distributed terminal receives parameter values ​​from the built-in communication parameter file, it may not be able to accommodate them. As an example, the transmission power cannot be specified by a communication parameter that specifies a transmission power higher than the maximum transmission power of the distributed terminal. In other words, in certain cases, the communication parameters may not be applied to the distributed terminal. In this case, as an example, the distributed terminal may not need to perform a transmission operation based on the communication parameters. In other words, the mobile distributed terminal must confirm its location and determine the communication parameters to use taking into account its terminal type and service type, etc.

[0081] As another example, a distributed terminal in a wireless distributed communication system may not update its own communication parameter file. For example, if the distributed terminal is located at a fixed location, such as a home appliance, the distributed terminal may not update its communication parameters. For example, in the case of a home appliance, since no special service changes are required, it is possible not to update the communication parameters for a specific distributed terminal, such as when a distributed modem is installed in the home appliance.

[0082] In addition, for example, if a communication parameter file stored in a distributed terminal needs to be periodically updated in a wireless distributed communication system, the distributed terminal may periodically connect to an update server via a communication network. For example, an operator of the wireless distributed communication system or a related distributed communication carrier may operate a server in consideration of periodic updates of the distributed terminal.

[0083] For example, if a distributed terminal that periodically updates its built-in communication parameters does not update them, the distributed terminal may have multiple functions and services restricted. Furthermore, the functions of the distributed terminal may be interrupted. For example, if updates are not performed, such as in the case of the traffic light service described above, problems may arise because communications with other distributed terminals may be disrupted. In other words, updating a distributed terminal that must periodically update its built-in communication parameters may be an essential operation for providing a service or function. Therefore, if a distributed terminal that must periodically update its built-in communication parameters does not update them, the service or function may be restricted.

[0084] For example, when the built-in communication parameters are periodically updated as described above, the distributed terminal may perform the update based on a preset number of times for a preset period. For example, a terminal that must periodically update its built-in communication parameters may be a mandatory update terminal. That is, the mandatory update terminal may periodically update its built-in communication parameter file. At this time, the mandatory update terminal may also update information regarding the usage period of the updated parameters.

[0085] As an example, referring to FIG. 4(a), a distributed terminal can be set with a parameter validity period or usage period after an update. For example, in FIG. 4(a), if the built-in communication parameter file is updated on July 15th, the distributed terminal can be granted a usage period until August 15th for the updated communication parameters. Also, as an example, if updates are performed once a month as shown in FIG. 4(b), the distributed terminal can be granted a usage period until August 31st. In other words, a mandatory update terminal can be set with a usage period for the updated parameters. As an example, the usage period can be set so that updates are performed a set number of times per week, month, quarter, or year. Also, as an example, a mobile distributed terminal can perform updates once a month or once a quarter.

[0086] In this case, when the usage period expires, various functions of the distributed terminal may be restricted. For example, all functions of the distributed terminal may be restricted. That is, as described above, operations may be restricted so as not to affect neighboring terminals. Therefore, in order to provide new services in a wireless distributed communication system, the communication parameter files of all distributed terminals must be updated.

[0087] As an example, Ecoland, a tourist destination on Jeju Island, and a distributed communications carrier may enter into a service contract and allocate fixed broadcast slots to the Ecoland area starting in September 2018. Consider the case where, of the 500 broadcast slots of the broadcast channel, the fixedly allocated slot numbers are 200 slots from 100 to 299. Referring to FIG. 5, the carrier must modify the built-in communication parameter file of the update server to prohibit all mobile distributed terminals in the Ecoland area from transmitting broadcast slots from 100 to 299 starting in September 2018. Assuming that mobile terminals must update their communication parameter files once a month, the carrier must modify the communication parameter file by the end of July so that all mobile terminals can update their communication parameter files before September begins. In the above example, if a mobile terminal does not update its communication parameter file within one month, the transmission of all broadcast slots in Ecoland for that terminal can be prohibited. As another example, that terminal may not be able to transmit broadcast slots in any region of the country. In other words, if a mandatory update terminal is not updating, its operation can be restricted so as not to affect other terminals.

[0088] For example, periodically updating the built-in communication parameter file can be very cumbersome for a user. Therefore, the communication parameter file can be updated automatically. For example, if a distributed modem is installed in a smart device, the built-in communication parameter file can be updated relatively easily. For example, while connected to WiFi, the update can be performed automatically in the early morning or late night hours when the user is usually asleep. Alternatively, if a user does not use the smart device for a long period of time, the smart device can be automatically updated in the wireless distributed communication system.

[0089] However, if the distributed terminal does not have a means for connecting to a communication network, it is difficult to automatically update the built-in communication parameter file. For example, in the case of a distributed terminal installed in a vehicle or a fixed distributed terminal installed in a store, the distributed terminal is not connected to a communication network, so the update operation may not be smooth. As another example, the update operation may not be smooth due to regional restrictions on the distributed terminal. For example, when traveling abroad, the distributed terminal as a smart device may not be able to update the built-in communication parameter file of the country.

[0090] Therefore, there may be a need for a method for manually or automatically updating built-in communication parameters for distributed terminals that have difficulty connecting directly to a communication network.

[0091] For example, among the distributed terminals, a distributed terminal capable of connecting to a communication network, such as a smart device, can connect to a server and download a built-in communication parameter file on behalf of a distributed terminal that has difficulty connecting directly to a communication network, and transmit the downloaded file to perform an update. More specifically, a distributed terminal having an Internet connection can connect to an update server and download the built-in communication parameter file of another distributed terminal, rather than its own built-in communication parameter file. The distributed terminal can then transmit the downloaded built-in communication parameter file of the other distributed terminal to the distributed terminal using wireless communication. In order for the update process to be performed automatically, it must be detected that the terminal that downloaded the built-in communication parameter file of the other terminal can connect to the update requesting terminal for distributed communication. Various methods for this detection can be provided in distributed communication. Therefore, if the presence of the update requesting terminal is detected via wireless distributed communication, the update providing terminal can automatically update the built-in communication parameter file of the update requesting terminal via wireless distributed communication. Considering the above-described operation, an integrated terminal, such as a smart device, can download the built-in communication parameter file of the corresponding update requesting terminal in advance. Furthermore, a user can set the smart device to perform a proxy update of the terminal in advance, and the present invention is not limited to the above-described embodiment.

[0092] For example, referring to FIG. 6, a mobile distributed terminal can connect to an update server via a communication network and request a built-in communication parameter file of a fixed terminal (S610). Then, the mobile distributed terminal can store the built-in communication parameter file of the fixed terminal received from the update server (S620). Then, the mobile distributed terminal can detect the corresponding fixed terminal through wireless distributed communication. At this time, the detection of wireless distributed communication is as described above. Then, when the mobile distributed terminal detects the fixed distributed terminal (S630), it can transmit the built-in communication parameter file to the fixed distributed terminal (S640). Here, the fixed distributed terminal can detect a distribution signal periodically transmitted by the mobile distributed terminal and, based on the detection, can receive and update the built-in communication parameter file.

[0093] Also, as an example, when a mobile distributed terminal detects a fixed distributed terminal, if a previously downloaded built-in communication parameter file does not exist, the mobile distributed terminal can request and download the built-in communication parameter file from the update server via the communication network.

[0094] 7, for example, a mobile distributed terminal may first detect a corresponding fixed terminal through wireless distributed communication (S710). At this time, if the mobile distributed terminal does not have the built-in communication parameters of the fixed terminal previously received as described above, the mobile distributed terminal may request the built-in communication parameter file of the fixed terminal from the update server (S720). Thereafter, the mobile distributed terminal may store the built-in parameter file received from the update server in the mobile distributed terminal (S730). Thereafter, the mobile distributed terminal may transmit the built-in communication parameter file downloaded wirelessly to the corresponding fixed terminal (S740). In other words, since the mobile distributed terminal first detects the fixed terminal but does not have the built-in communication parameter file for the fixed terminal, the mobile distributed terminal may immediately download the built-in communication parameter file for the fixed terminal from the update server via the Internet and then transmit it to the fixed terminal.

[0095] For example, the distributed terminal installed in the vehicle may be a fixed terminal and may update the built-in communication parameter file from the vehicle owner's smart device distributed terminal. In this case, the distributed terminal installed in the vehicle may perform distributed communication with the smart terminal through distributed communication.

[0096] As another example, when traveling abroad, even a smart device distributed terminal often has difficulty connecting to the Internet. For example, a smart device may only be capable of roaming for phone functions, and data roaming may be prohibited overseas. Therefore, the smart device may manually download a built-in communication parameter file for the region to be traveled in advance. However, manually downloading communication parameters may be cumbersome for the user. Therefore, the present invention allows the mobile distributed terminal to automatically download the communication parameter file for the region.

[0097] The above-described situation is merely an example, and can be similarly applied to other regional restrictions. That is, the smart device distributed terminal can automatically store communication parameter information in advance, taking into account that the communication network is restricted by regional restrictions.

[0098] For example, referring to FIG. 8, a mobile distributed terminal can connect to a server via the Internet and receive both a communication parameter file for a mobile terminal and a communication parameter file for a fixed terminal. In this case, the fixed terminal can receive and update its own built-in communication parameter file from the mobile distributed terminal, while also receiving the built-in communication parameter file of the smart device distributed terminal. Thereafter, the fixed terminal can again transmit the received built-in communication parameters of the mobile terminal to another mobile terminal. In other words, the fixed terminal can relay the transmission of the built-in communication parameters of another mobile terminal.

[0099] As another example, a fixed distributed terminal can directly connect to an update server, in which case the fixed distributed terminal can acquire its own built-in communication parameter file and perform updates.

[0100] As another example, a case where there are multiple fixed distributed terminals can be considered. For example, referring to FIG. 9, a fixed distributed terminal can receive and store a communication parameter file of a mobile distributed terminal via a communication network. At this time, the mobile distributed terminal can receive and update a built-in communication parameter file from the fixed distributed terminal. That is, the distributed terminal can receive and update a built-in communication parameter file from the fixed distributed terminal via distributed communication. At this time, the mobile distributed terminal can allocate a slot to receive the communication parameter file and transmit a built-in communication parameter update request. Thereafter, the fixed distributed terminal can receive the request and perform slot occupation contention to transmit the update request in a frame subsequent to the received request. At this time, the fixed distributed terminal can receive a slot allocation through contention and transmit a response including the built-in communication parameter file through the allocated slot. Specifically, the fixed distributed terminal can request a communication parameter file from a mobile terminal (S910). At this time, the fixed distributed terminal can receive and store the built-in communication parameter file from an update server (S920). Thereafter, the fixed distributed terminal can receive a communication parameter file update request from the mobile distributed terminal (S930). At this time, the fixed distributed terminal may perform allocation contention for the slot in which the request was received in a frame subsequent to the frame in which the request was received (S940). That is, the fixed distributed terminal may perform contention because it needs to receive slot allocation in order to transmit a response. After that, when the fixed distributed terminal receives slot allocation through contention, it may transmit an updated communication parameter file to the mobile terminal via wireless (S950).

[0101] As another example, consider a case where the fixed distributed terminals are connected by wire. In this case, the fixed distributed terminal can determine, through wired communication, which terminal will respond to the request. That is, in FIG. 9, the fixed distributed terminal can provide the built-in communication parameters via the fixed distributed terminal determined through wired communication, without contention for slot occupation.

[0102] More specifically, referring to Fig. 10, fixed distributed terminals can communicate with each other. At this time, a fixed distributed terminal that receives a request from a mobile distributed terminal can transmit a response through a slot assigned by the update request terminal. At this time, if the fixed distributed terminals are connected via a wired connection, a fixed distributed terminal that provides an update file can be determined from among the fixed distributed terminals. Thereafter, the mobile distributed terminal can receive a built-in communication parameter file from the determined fixed distributed terminal.

[0103] 10, a fixed distributed terminal may request a communication parameter file for a mobile terminal from an update server (S1010). Thereafter, the fixed distributed terminal (or fixed distributed terminal, etc.) may store the communication parameter file received from the update server (S1020). At this time, the fixed distributed terminal may receive a communication parameter file update request from the mobile distributed terminal (S1030). At this time, if the fixed distributed terminal is connected via wired communication as described above, the fixed distributed terminal may determine one fixed distributed terminal to provide the updated communication parameter file (S1040). In other words, the fixed distributed terminal determined via wired communication may provide the communication parameter file to the mobile distributed terminal without contention for a separate slot allocation (S1050).

[0104] As another example, the above-mentioned built-in communication parameters may be transmitted via WiFi Direct or Bluetooth (registered trademark). As described above, the built-in communication parameters may also be transmitted via a wireless distributed communication means, and are not limited to the above-mentioned embodiment. As another example, in the case of a distributed terminal installed in a vehicle, the communication parameter file may also be updated by a distributed road unit (RSU). As an example, an RSU, which is a distributed terminal installed on a road, may be connected to a central control station that controls it. In this case, the central control station may be connected to a communication network. Therefore, the central control station may transmit the built-in communication parameter file used by the vehicle to the road RSU, and the road RSU may transmit the built-in communication parameter file to the vehicle via distributed communication upon request from the vehicle.

[0105] Also, for example, there may be multiple types of built-in communication parameter files used in a vehicle. Specifically, a vehicle's distributed terminal may require not only a vehicle communication parameter file used in a transportation system but also a communication parameter file used for wireless distributed communication with a general smart device distributed terminal or a store's distributed terminal. That is, the built-in communication parameter file for vehicle communication can be used for operation of the transportation system and the vehicle. Furthermore, the smart device communication parameter file can be used for communication between a vehicle and a smart device or between a vehicle and a fixed terminal in a store. For example, the vehicle's distributed terminal can receive store information and perform orders and payments using the settings in the smart device communication parameter file. That is, multiple communication parameters can be set in one distributed terminal. While the above description has been given based on a vehicle for convenience of explanation, it is obvious that the same method can be applied to other distributed terminals.

[0106] As another example, the branch road unit can provide a built-in vehicle communication parameter file, which can be updated periodically and has a small file size, and can therefore be provided to the branch road unit.

[0107] In addition, as an example, the distribution road unit can provide not only the vehicle built-in communication parameter file but also the smart device communication parameter file, that is, the distribution road unit (or RSU) is a distribution terminal and can provide information for updating the vehicle built-in communication parameters, and is not limited to the above-mentioned embodiment.

[0108] As another example, a plurality of built-in communication parameter files can be created in the distributed terminal. For example, when a smart device is a distributed terminal, the smart device can provide or receive a plurality of services, so the communication parameters are variable depending on the situation.

[0109] For example, a distributed terminal as a smart device may have a built-in communication parameter file containing 100 parameters, and one region (e.g., one country or one province) may be divided into 10,000 regions. For example, if one communication control parameter is 2 bits, the size of the entire built-in communication parameter file may be 2M bits (=2*100*10000). To reduce the size of the communication parameter file, multiple parameters may be distinguished. The parameters may be divided into files for parameters that are rarely updated and files for parameters that fluctuate frequently. For example, as described above, 60 of the 100 parameters may be fixed values ​​that are rarely updated in the region. However, this is merely an example for convenience of explanation and is not limited to the above embodiment. As described above, parameters that are rarely updated may be updated only when necessary. That is, the above parameters may be updated based on an event trigger. Meanwhile, the remaining parameter files (e.g., 40 parameters) may be updated periodically. That is, among the multiple parameters, some parameters can be updated based on event triggering, and other parameters can be updated based on a preset cycle. In this case, in the above example, the size of the built-in communication parameter file having 40 parameters may be 0.8M bits (=2*40*10000). That is, when multiple parameters are taken into consideration, the parameters can be distinguished and operated. For example, referring to FIG. 11(a), the parameter file can be distinguished into fixed parameters and variable parameters (or regional parameters). More specifically, the parameters can be distinguished into fixed parameters and variable parameters distinguished by each region. This allows different operations to be performed for each parameter.

[0110] As another example, parameter changes can be permitted to determine the priority of files. For example, referring to FIG. 11(b), the same parameter may exist in multiple files. In this case, the parameter value in the file with the higher priority can be used. Here, changing the parameter can mean giving a higher priority to a file related to the location of the terminal (or user) or a service used by the terminal (or user).

[0111] Specifically, a basic file containing all parameters may exist, with a priority of "0." Here, files related to cities, suburbs, countryside, mountains, coasts, and oceans may exist, with each file having a priority of "1." However, the above is merely an example for ease of explanation and is not limited to the above embodiment. That is, each file may exist based on the user's location, service, etc., and each priority may be set. For example, if the location attribute of the terminal (or user) is a city, the parameters in the city file among the parameters in the basic file may be changed. That is, the parameters in the city-related file may be applied preferentially. For example, a case may be considered in which the transmission power is set to 23 dBm in the basic file and 25 dBm in the city file. In this case, if the location attribute of the terminal (or user) is a city, the transmission power may be set to 25 dBm based on the parameter change described above.

[0112] As another example, consider a case where the priority of the emergency service file is "2" and the transmission power is "33 dBm." In this case, the terminal changes the parameters based on the emergency service file, so that even if the terminal is in a city, the terminal can transmit the emergency service signal at 33 dBm. That is, the parameter value can be changed according to the terminal's situation. In this case, as an example, the parameter can be changed by replacing the existing value with a new value. As another example, the parameter can be changed by adding a change amount to the existing value. As an example, in the above example, if the transmission power of the file with priority "0" is 23 dBm and the transmission power of the file with priority "1" is +3 dBm, the final transmission power can be changed to 26 dBm.

[0113] Also, for example, a parameter conversion file can be further generated to reduce the size of parameters. For example, channel frequency values ​​can be expressed with very high precision. Therefore, a large number of bits may be required to express the channel frequency value. For example, if the center frequency of a broadcast channel is 2785.25 MHz, 20 bits or more may be required to express the frequency. In this case, the number of broadcast channels used in one country can be set to at least one and not more than four. However, this is merely an example and is not limited to the above embodiment. Therefore, in the parameter file, the center frequency of the broadcast channel can be expressed with two bits, allowing channels 0, 1, 2, and 3 to be used. In this case, the parameter conversion file can express the detailed frequency values ​​represented by broadcast channels 0, 1, 2, and 3. Therefore, only one parameter conversion file is required for one country or region, thereby reducing the size of the parameter file.

[0114] For example, the size of an internal file can be reduced by using a location type parameter file in a format similar to that of a parameter conversion file. More specifically, a divided area parameter file can be generated for each divided area. The divided area parameter file can specify the type of each divided area. However, in order to do this, the current location and type of the terminal need to be confirmed. For example, the terminal can confirm its location and type through a map file in which the location type is set. Meanwhile, the type of a divided area can be categorized into at least one of urban, suburban, rural, coastal, ocean, mountain, forest, and river. However, the above is merely an example, and other types can also be set. That is, a different location type can be set for each location. In this case, a location type parameter file can be generated for each location type. That is, parameters can vary depending on the location type. Specifically, the transmission power in an urban area can be different from that in a rural or coastal area. Generally, a small transmission power is used in an urban area, while a larger transmission power is used in a rural area. At this time, considering parameter changes and file priority, parameter values ​​according to the characteristics of the divided regions can be generated as divided region parameter files. Also, a separate parameter file can be specified for a specially designated area regardless of the divided region. At this time, as an example, as described above, the specially designated area can be designated based on multiple factors. For example, the specially designated area can be designated by the wireless distributed communication system based on a contract (for example, it can be set by a contract with a wireless distributed communication carrier). At this time, the distributed communication system can provide special parameters for the contracted area through a contract parameter file.

[0115] For example, if Ecoland is set up in a special region through the system (i.e., if Ecoland signs a contract with a distributed communications carrier), it can exclusively use 200 broadcast slots of the broadcast channel in the entire Ecoland region. The parameters for such a contracted region can also be provided as a single parameter file.

[0116] As another example, the contract parameters of the contracted area can be broadcast by the fixed distributed terminal in the corresponding area in a broadcast slot. In this case, the mobile distributed terminal can receive the broadcast slot in advance in consideration of the service and can receive the related parameters whether it is in the contracted area or not.

[0117] In a wireless distributed communication system, parameters to be referenced may differ depending on the location of a terminal. Furthermore, parameters may be set differently depending on which service the terminal uses. Therefore, a service parameter file needs to be generated separately. That is, different parameters need to be generated depending on not only the location of the terminal but also the service. For example, even if a terminal is located on the coast, a short-distance chat service, a short-distance call service, or a rescue request service may be required. In this case, each service may have different communication parameters. Such service-specific parameters can be referenced when using the corresponding service. Furthermore, the above-described service-specific parameters may be applied if they have a higher priority than the currently set parameters. Conversely, the above-described service-specific parameters may not be applied if they have a lower priority than the currently set parameters.

[0118] Also, for example, the services provided by distributed modems are very diverse. For example, a very light and small distributed terminal such as a wearable device may mainly communicate with a smartphone distributed terminal. In this case, communication parameters applied to this wearable distributed terminal may differ from general parameters. Therefore, taking the above into consideration, existing parameters may be replaced based on a parameter file with a higher priority. Also, for example, a set of all parameters required for the operation of the distributed modem may be an "active parameter set." More specifically, the active parameter set may be overwritten sequentially from parameters in a file with a lower priority to parameters in a parameter file with a higher priority.

[0119] More specifically, referring to FIG. 12, an active parameter set to be actually used can be configured from multiple files. First, the active parameter set can receive basic parameter values ​​from a base parameter file. The base parameter file may vary depending on the country or region and is not limited to the above-described embodiment. Second, the location information and type information of the terminal can be confirmed. Third, based on the location information, parameters related to the current location of a divided region parameter file can be overwritten into the active parameter set. Next, as described above, parameters appropriate for the location type for the confirmed location can be overwritten into the active parameter set. Next, parameters related to the type of service executed by the terminal (or user) can be overwritten into the active parameter set. For example, the location information and the location type can be confirmed and overwritten together. Finally, if the current location of the terminal is in a contracted area, the active parameter set can be overwritten with contract parameters.

[0120] In this case, as an example, the active parameter set may exist only within the distributed modem. As another example, the active parameter set may exist outside the distributed modem. That is, the wireless distributed terminal may configure an active parameter set outside the distributed modem and directly load it into the active parameter set of the distributed modem as needed. As another example, the distributed terminal may have an active parameter set only within the distributed modem and update parameters within the distributed modem as needed, and this is not limited to the above-mentioned embodiment.

[0121] As another example, distributed communication parameters may be stored in advance in order for a distributed terminal, such as a smart device, to receive prompt service provision. In this case, the communication parameters of the smart device may be determined based on its terminal type, its location, and the service to be used. For example, if the terminal type of the smart device is fixed and the service to be provided has not yet been determined, the communication parameters of the smart device may be determined based on the location of the smart device. A distributed terminal can easily obtain its location via mobile communication signals, Wi-Fi, GNSS, etc. Therefore, in order for a mobile terminal to quickly prepare a service, it may determine the divisional region to which it belongs from its location and pre-store the communication parameters of the corresponding divisional region from a location attribute file. That is, parameters may be loaded into the distributed modem, or loading values ​​may be prepared in advance. Furthermore, parameters corresponding to a service may be used in a manner that partially replaces location-related parameters. That is, when a user inputs the use of a service, the distributed terminal may immediately load pre-prepared parameter values ​​or reload parameters related to the service from the pre-loaded parameters. Meanwhile, for example, the communication parameters included in the built-in communication parameter file may include at least one of the type and number of wireless distributed communication channels, the center frequency and bandwidth of each channel, the mapped contention proxy channel frequency, reserved designated slot information, reserved fixed slot information, priority setting slot information, superframe information, and slot group information. As another example, the communication parameters may further include at least one of the modulation order used in each service or slot, basic transmission power, maximum transmission power, encryption information, encryption method, password information, and password method. As another example, the above-mentioned parameters may be set to urban, suburban, rural, mountainous, ocean, coast, forest, river, etc. as parameter values ​​for location attributes. For another example, the above-mentioned parameters may include basic language information and information on mobile communication carriers permitted by the smart device, and are not limited to the above-mentioned embodiment.In addition, the parameters include channel information used for each service, minimum and maximum service allocation slot numbers, etc. In addition, for example, parameters for other information may be set, and are not limited to the above-described embodiments.

[0122] As another example, wireless distributed communication systems may include the AIS system used by ships and the ADS-B system used by aircraft. However, these systems do not support point-to-point communication well and are primarily intended to provide information via broadcasting. For example, wireless distributed communication has not been widely commercialized due to communication resource contention and hidden node problems. For example, the above-mentioned technology and Reference 1 can solve these problems. Based on the above-mentioned technology and Reference 1, various types of terminals may emerge in wireless distributed communication systems. First, there are mobile terminals such as mobile communication terminals, ships, drones, and vehicles. Second, there are fixed terminals, i.e., terminals that are fixed outdoors, such as in stores, department stores, and amusement parks. Third, there are indoor terminals such as home appliances such as rice cookers, ovens, and air conditioners. In a wireless distributed communication system where various terminals and services coexist, addresses can be set in relation to IP, but since it is not easy to connect all of the various terminals to the Internet, a more efficient addressing method unrelated to IP may be required. Also, a service-specific address may be required in a specific service area regardless of the terminal. Therefore, the following provides a method for setting addresses taking into account the type of distributed terminal so that distributed communication services can be provided more efficiently.

[0123] Furthermore, as an example, the following description will be given based on the above and Reference 1, assuming that various services are provided to distributed terminals in a distributed communication system. For example, a terminal in a wireless distributed system can be assigned an address. As an example, the terminal in the wireless distributed system may be at least one of a mobile communication terminal, a ship, a vehicle, a drone, and a fixed terminal. However, the above-mentioned terminal is merely an example and is not limited to the above-mentioned embodiment. That is, the terminal in the wireless distributed system may be a mobile terminal or a fixed terminal and may have various forms. In this case, an address can be assigned to the terminal in the wireless distributed system. As an example, an address can be assigned to the terminal in the wireless distributed system based on the characteristics of the terminal. In this case, if the address is assigned taking into account the characteristics of the terminal, the terminal can efficiently provide services based on the address information.

[0124] For example, a mobile terminal can notify whether information of the terminal is reliable by sending its unique number. Also, for example, the mobile terminal can notify whether the terminal is properly registered in the system. In this case, the mobile terminal is a mobile communication terminal and can provide services via a conventional communication network. For example, if the mobile terminal further includes a distributed communication modem, the service area can be expanded and services can be provided efficiently. In this case, the unique number of the terminal can be used as an address value to ensure reliability in the wireless distributed communication system. That is, a mobile terminal in the wireless distributed communication system can construct a public trusted packet using an address value consisting of the unique number, thereby ensuring reliability in the wireless distributed communication system.

[0125] As another example, a fixed terminal in a wireless distributed communication system can set an address using its own latitude, longitude, and altitude values. That is, considering that the fixed terminal is fixed, the fixed terminal can directly set location-related information as physical information as an address value. In this case, as an example, a mobile terminal in the wireless distributed communication system can calculate the location of the mobile terminal using the physical location information of the fixed terminal, considering its relationship with the fixed terminal.

[0126] More specifically, the smart device is an integrated terminal and can be equipped with a modem for a conventional communication network and a distributed communication modem for the wireless distributed system. That is, the smart device can simultaneously use conventional mobile communication and wireless distributed communication. In this case, the smart device can set a different wireless distributed communication address for each service. That is, by assigning a separate address to each individual service, each service can be distinguished. For example, each service in the smart device can be executed by a separate program. In this case, when each program in the smart device is executed, a separate address can be set for each program execution. That is, the address of the distributed terminal can be different each time the program is executed.

[0127] In this case, as described above, when each address value is set for each execution of the program, the address must include a field specifying the type of terminal or use a different communication frequency depending on the type of terminal. In other words, when configuring address information, the type of terminal can be considered in consideration of the above-mentioned circumstances.

[0128] More specifically, if a field specifying the terminal type is included in the address, the terminal may include other information in the above-mentioned field, which varies depending on the terminal type. As an example, the terminal type may be at least one of a smart device, a ship, a vehicle, and a home appliance. However, this is merely an example, and other types may also be included. For convenience of explanation, the following description will be based on the above-mentioned types. As an example, referring to FIG. 13, the address information may include a field for the terminal type. In this case, in FIG. 13(a), the first two bits may indicate that the address is generated by the service itself, and the remaining address fields may include address information generated by each service.

[0129] Also, referring to Figure 13(b), the first four bits can indicate that the address information is set by the system, and the remaining address fields can contain address information set by the system.

[0130] Also, referring to Figure 13(c), the first four bits "1001" can indicate that the address is set by the user who purchased the device. In this case, the remaining address fields can contain address information set by the user.

[0131] Also, referring to FIG. 13(d), the first two bits "01" may indicate that the address is set by the mobile terminal. Here, "subtype" may indicate the subtype of the mobile terminal. For example, "00" may indicate a mobile communication terminal, "01" may indicate a vehicle terminal, "10" may indicate a drone terminal, and "11" may indicate a marine terminal. However, this is merely an example and is not limited to the above-described embodiment. In other words, the first two bits indicate that the address is a mobile terminal, and the specific type of the mobile terminal may be indicated by the next two bits, but is not limited to the above-described embodiment.

[0132] 13(e), the first two bits "00" can indicate that the address is set by the fixed terminal. In this case, the remaining address field can include information on longitude, latitude, and altitude as physical location information for the fixed terminal, but is not limited to the above embodiment.

[0133] However, the above-mentioned Figure 13 is merely an example and is not limited to the above-mentioned embodiment. In other words, the distributed terminals can be distinguished by setting their addresses according to the characteristics of the terminals. This allows the distributed terminals to provide services efficiently, which will be described below.

[0134] As an example, based on the above-mentioned FIG. 13, a smart device in a wireless distributed communication system can operate based on a conventional mobile communication network and a distributed communication network. In this case, a telephone number can be set as identification information for the smart device based on the conventional mobile communication network. The telephone number set by the smart device can also be used in the wireless distributed communication system. More specifically, the 32-bit address shown in FIG. 13(d) can be set to a value generated using the last 8 digits of a mobile communication telephone number after removing "010." Each decimal digit can be expressed using 4 bits. Therefore, an 8-digit telephone number can be expressed using 32 bits (4*8=32). For example, expressing an 8-digit decimal number in binary may require 27 bits. Here, when a terminal in a wireless distributed communication system sets its address as a mobile communication telephone number, the terminal can link services provided by distributed communication with mobile communication services. As an example, consider a case where a user connects to a distributed fixed terminal installed in a restaurant via a smart device based on the wireless distributed communication system and requests a waiting number.

[0135] As an example, referring to FIG. 14, a smart device (or integrated terminal) can receive restaurant information through distributed communication. For example, the restaurant information can include information about currently available seats and queue numbers, and is not limited to the above-described embodiment. For example, in FIG. 14, the smart device can receive information that there are no available seats and that the current queue number is 4. The smart device can then request queue number 5 via a fixed terminal using a wireless distributed communication system. As described above, the distributed communication modem sets its own address as the mobile communication phone number of the terminal, so the fixed terminal of the restaurant can simultaneously check the address and phone number of the requested terminal. Therefore, the fixed terminal of the restaurant can transmit a queue number tag to the smart device and store the number tag and phone number to provide services. Furthermore, when a seat becomes available at the restaurant, the fixed terminal of the restaurant can call the person in the queue number order through distributed communication. In other words, as described above, when a smart device or terminal supports a wireless distributed system and a conventional mobile communication system, address information is linked and set, so related information can be used as described above.

[0136] On the other hand, the communication distance of a wireless distributed communication system may be limited. For example, the communication distance of distributed communication may be approximately 300 meters. In this case, when a smart device receives a service from a fixed terminal as described above (e.g., after receiving a queue number), if the smart device moves farther from the fixed terminal, it may fall outside the range of the wireless distributed communication system. In other words, even if the smart device's queue number arrives, the store cannot call the smart device via distributed communication. In the above case, the fixed terminal cannot receive an ACK for the call from the smart device, as shown in Figure 2b. Therefore, if the fixed terminal cannot receive the ACK, it can provide related information to the smart device via a mobile communication network. In other words, even when operating based on a distributed communication system, service provision efficiency can be improved by linking with a conventional communication network.

[0137] Specifically, if the storekeeper's smart device shown in FIG. 14 is also equipped with a distributed modem, the fixed terminal can inform the smart device that it has not received an ACK through distributed communication. As another example, if the fixed terminal does not receive an ACK from the smart device through distributed communication, the fixed terminal can transmit information about the failure to receive an ACK to the storekeeper's smart device through a wireless distributed communication system. For example, since the storekeeper's smart device is always included in the wireless distributed communication system in relation to the fixed terminal, message transmission does not fail. That is, if the fixed terminal cannot receive an ACK message from the smart device, it can transmit related information to another pre-configured smart device. Then, the distributed communication modem of the storekeeper's smart device can transmit the information to a higher layer of the smart device. That is, the smart device can provide the information to a running application. At this time, the higher-layer application can transmit the related information to the smart device through a conventional mobile communication network. That is, the higher-layer application can send a call text message to the mobile communication system using the waiting number and the customer's phone number, or provide the information through a messenger. For example, both the smart device and the restaurant owner's smart device use conventional mobile communication networks, so the message can be transmitted without distance restrictions and the restaurant owner can return to the message based on the message.

[0138] That is, when a terminal in a wireless distributed communication system sets the address of a distributed terminal modem via a conventional communication network, the terminal can receive services efficiently.

[0139] Also, as an example, if the smart device does not set identification information (e.g., a telephone number) as the distributed communication address, the smart device may add the phone number information of the smart device to the message to be transmitted to the fixed terminal, and transmit the message, but is not limited to the above-described embodiment. In other words, the smart device may perform the above-described operation by configuring the address for distributed communication in a different form and transmitting the address to the fixed terminal including the smart device information, but is not limited to the above-described embodiment. As an example, the phone number of the smart device may be personal information. In this case, if the distributed communication address information is configured as a telephone number, there is a risk of security issues and issues in handling personal information, so the operation may be as described above.

[0140] Also, for example, if a smart device user does not want to disclose their phone number, the smart device may use a different address assigned by the system. For example, referring to FIG. 13 above, the distributed communication address of the smart device can be changed depending on the characteristics of the service.

[0141] As another example, a distributed terminal in a wireless distributed communication system may be a mobile terminal. While the following description uses a ship as a mobile terminal, this is not limiting. For example, if the terminal in the wireless distributed communication system is a ship, the terminal address may be set to the ship's Maritime Mobile Service Identity (MMSI). Also, as another example, if the terminal in the wireless distributed communication system is of another type, the address may be set based on the terminal type, as described above. As an example, a user may travel via a means of transportation. For example, the means of transportation may be a ship or a vehicle. In this case, the wireless distributed communication address of the user's smart device may be set to the MMSI of the ship, which is the means of transportation. Referring to FIG. 13(d) above, the first four bits of the address field may be set to "0111." In this case, the smart device may periodically broadcast the position information of the ship via the wireless distributed communication system. That is, the smart device may periodically broadcast its position information on behalf of the means of transportation. Since the broadcasted address information includes the ship's MMSI as described above, even small vessels can notify their location without an Automatic Identification System (AIS). Also, for example, if a large vessel is equipped with a distributed communication modem, it can check the location of nearby small fishing boats, thereby preventing accidents.

[0142] As a specific example, referring to FIG. 15, a terminal moving via a mobile means (e.g., a passenger ship, a small boat) can set the first four bits in FIG. 13 described above to "0111." For example, each mobile means can operate based on a wireless distributed communication system. In this case, the mobile means can detect that the terminal is located on the mobile means through the wireless distributed communication system and can provide mobile-means-based services through the terminal. In this case, the address information of the terminal can be set based on the mobile means described above. For example, as described above, the first four bits can be set to "0111." In other words, a terminal located on a mobile means can be set with the address information that can indicate that it is a terminal located on a mobile means as a terminal type. In this case, for example, a ship or a terminal can communicate via the wireless distributed communication system. In this case, as described above, the address value received in distributed communication can indicate the type of terminal moving via a mobile means, so it can be known whether it is located on a mobile means. In this case, the other wireless distributed communication signals sent by the people on the boat in Figure 15 do not specify the terminal type as a ship using their own address value, nor do they set the MMSI as their address, so the boat receiving this signal can clearly know that the signal is information unrelated to the boat. For example, if a domestic boat operates based on a wireless distributed communication system, it can distinguish between domestic boats and boats from other countries, and illegal fishing operations can be cracked down on based on this.

[0143] As another example, a terminal address may be set based on the location of a fixed terminal in a wireless distributed communication system. For example, the address of the fixed terminal shown in FIG. 13(e) above may be the address of the fixed terminal. In this case, the location information of the fixed terminal may be set as the address of the fixed terminal as described above. A terminal included in a wireless distributed communication system may determine its own location based on address information received from the fixed terminal. For example, referring to FIG. 16, multiple fixed terminals may be disposed in the wireless distributed communication system. In this case, when a terminal in the wireless distributed communication system receives a signal from a fixed terminal, the terminal may obtain location information of the fixed terminal from the address information of the fixed terminal. Therefore, the terminal may calculate its own location based on the location information of the fixed terminal. For example, the terminal may calculate its own location through triangulation. As a result, a terminal in a wireless distributed communication system may confirm its location information without a location information receiving modem such as a GPS. As another example, the terminal may calculate its own location, the location of the fixed terminal, and related information using the received address, and transmit the above information to a higher layer of the terminal. That is, the above information may be transmitted to other programs in the terminal. As a result, the terminal may use the above location information and related information in programs.

[0144] As a specific example, FIG. 16 illustrates a case in which a terminal receives restaurant information broadcast by other fixed distributed terminals and arranges the restaurants in order of proximity to the terminal. Referring to FIG. 4, multiple restaurants can broadcast information about the restaurants through a wireless distributed communication system. The restaurant information may include the restaurant's name, menu information, etc., and is not limited to the above-described embodiment. Terminals in the wireless distributed communication system can check the location information of each fixed terminal based on a signal transmitted from a restaurant, which is a fixed terminal (S1610). The terminal can also calculate its own location using the location value of each restaurant, the delay time of each signal, and the received power value from the signal transmitted by the fixed terminal (S1620). The distributed modem of the terminal transmits the information to a higher layer of the terminal, which can then be used by other programs. For example, the terminal can sequentially notify the nearest distributed terminal among nearby fixed terminals (e.g., restaurants) based on the information (S1630). To express a location with an accuracy of about 1 m, a large number of bits may be required to express the latitude and longitude. Therefore, the address information can be set using only the portion after the degrees, minutes, and seconds representing the latitude and longitude. For example, a terminal having multiple communication modems can obtain information regarding the portion before the degrees, minutes, and seconds based on other communication signals, such as at least one of a GPS signal, a mobile communication signal, and a Wi-Fi signal. Accurate location information can also be obtained using address information of the fixed terminal, as described above. For example, the address information may include information regarding height, as described above. For example, height may be expressed in 1-meter intervals relative to sea level, and if 10 bits are used, height can be expressed up to 1023 meters. However, this is merely an example and is not limited to the above-described embodiment. For example, height may be measured relative to the earth's surface at the corresponding latitude and longitude position.

[0145] As another example, an address may be specified by a user or the system itself in a wireless distributed communication system. For example, the above-described FIGS. 13(b) and 13(c) may be cases where an address is set by a user or the system. For example, consider a case where a user purchases a terminal. In this case, as shown in FIG. 13(b), the terminal may be equipped with a unique number assigned by the terminal company. For example, as shown in FIG. 13(b), the first four bits of the address may be "1000." As another example, the terminal address may be set by a user itself. In this case, as shown in FIG. 13(c), the first four bits of the address may be "1001," followed by an 8-bit terminal type field. The remaining 24 bits of the address field may be set directly by the purchaser. For example, if a user sets the 24 bits directly, the user can systematically manage terminals included in the same wireless distributed communication system. For example, if a wireless distributed communication system is set in a home and the electronic devices included in the home are individual terminals, the user may set the addresses of the electronic devices based on the above-described FIG. 13(c). That is, the first four bits of the address field are "1001," the four bits indicating user setting and the eight bits indicating the terminal type are set based on pre-defined information, and the remaining 24 bits can be set by the user. For example, the eight bits can be set to different values ​​depending on the type of electronic device, and the remaining 24 bits can be set in the same way across the same wireless distributed communication system. That is, electronic devices in a home can have the same 24-bit value, and this is not limited to the above-described embodiment. For example, the distributed terminal modem of a smart device can commonly request information from home appliances with the same last 24 bits as address information.

[0146] More specifically, referring to FIG. 17, a wireless distributed communication system may include a rice cooker, a printer, a gas range, a washing machine, a TV, an oven, and an air conditioner in a home. Each of these devices may have a device type field value of h'01, h'02, h'03, h'04, h'05, h'06, and h'07. That is, the field indicating the terminal type may be set to the above-mentioned value. For example, a 24-bit address value set directly by a user may be h'1a2b3c. That is, the distributed terminals in a home may be set to the same 24-bit address value by the same user. The distributed terminal modems of the smart devices may commonly request status reports for each electronic device based on the same address value, as described above. Furthermore, the distributed terminal modems of the smart devices may simultaneously transmit information to the electronic devices based on the same address value. The above examples are provided merely for convenience of explanation and are not limited to the above-mentioned embodiment.

[0147] As another example, only some of the 24 bits set by the user may be set to a common value. As an example, the first 8 bits of the 24-bit address value may be set to be different, and the last 16 bits may be set to h'2b3c. Then, when requesting a status report, status information may be requested from a terminal whose last 16 bits of the address value are h'2b3c. As a specific example, multiple devices of the same terminal type may exist in a home. For example, multiple TVs may exist in a home. In this case, since it is not possible to distinguish terminals based on the above-mentioned terminal type information, some of the 24-bit address values ​​may be set to be different, thereby distinguishing terminals of the same type. Meanwhile, as described above, some of the 24-bit address values ​​may be set to be the same, and requests may be received or transmitted simultaneously, and this is not limited to the above-mentioned embodiment.

[0148] As another example, a terminal in a wireless distributed communication system may be a mobile terminal. For example, the terminal may be a drone or a vehicle. In this case, the drone or vehicle may set its address value to a unique number or a value generated from the unique number. Since the address value is set to the unique number, a terminal that identifies or inspects the drone or vehicle can confirm whether the address value of the terminal is valid.

[0149] More specifically, an address of a vehicle terminal in a wireless distributed communication system may be set using a vehicle's unique number. For example, a vehicle may have a license plate, and the vehicle number may also be a unique number. As another example, a unique number may be assigned to the vehicle itself. In this case, even if the owner or license plate of the vehicle changes, the vehicle's unique number can be maintained, thereby enabling continuous identification of the vehicle. As a specific example, if a unique number is assigned to a stolen vehicle and information about the unique number is included in the distributed communication system, the stolen vehicle can be identified through the wireless distributed communication system. As another example, even if the stolen vehicle removes the distributed communication terminal, it is possible to identify the vehicle that does not respond when requesting information through distributed communication. Also, although the above example is based on a vehicle, the same can be applied to a drone or other mobile terminal. That is, a unique number is assigned to a mobile terminal and the unique number is set as address information, thereby enabling identification of the mobile terminal.

[0150] As another example, as described above, a drone terminal in a wireless distributed communication system can be configured to have a terminal address set using the drone's unique number. For example, when a drone is operating, the drone's unique number can be broadcast for safety reasons. In particular, a drone can broadcast information about its position and speed through distributed communication to avoid collisions between drones. In this case, the drone can transmit a broadcast packet with the drone's unique number as the source address. For example, if a unique number is assigned to every drone, the efficiency of managing illegal drones can be improved.

[0151] Based on the above, a method for improving communication reliability using a unique number address value will now be described. Consider, for example, the case where a vehicle uses its own unique number as a distributed communication address, as described above. In this case, a specific terminal may receive the broadcast address value of other terminals in real time. In this case, the specific terminal may broadcast the received address value of other terminals, which may lead to confusion with other terminals. In consideration of this, monitoring for stolen terminals is impossible. Therefore, if a specific terminal changes its own address to the address of another terminal received wirelessly and transmits it, it cannot be identified. In consideration of the above, if each distributed terminal encrypts and transmits its data, other terminals receiving the information cannot verify the information. More specifically, referring to FIG. 7, a vehicle can be considered as a terminal in a wireless distributed communication system. For example, when a vehicle breaks down, the vehicle transmits breakdown information through the wireless distributed communication system, and the information is received by a fixed distributed unit installed on the road and surrounding vehicles. In this case, if the broken-down vehicle encrypts and transmits its accident information, the surrounding vehicles cannot receive the information. Conversely, if the information is not encrypted, other terminals or vehicles cannot trust the information.

[0152] Therefore, in consideration of the above, it is necessary to check the reliability of signals transmitted by terminals in a wireless distributed communication system. Hereinafter, checking the reliability as described above will be referred to as a "public reliability check." Furthermore, communication using the public reliability check will be referred to as a "public trusted communication," and a packet to which the public reliability check method is applied will be referred to as a "public trusted packet." Furthermore, the reliability bits added for the public reliability check in the above packet will be referred to as a "public reliability field." However, these are merely names used for convenience of explanation, and other names performing the same operation may also be used.

[0153] For example, referring to FIG. 18, a public trust packet including a public trust field can be constructed. In this case, the number of bits of the 'public trust field' can be determined by the system. For example, the public trust field can be generated using a unique number assigned to a mobile distributed terminal such as a vehicle or a drone. For another example, the public trust field can be generated based on the unique number of the distributed terminal and additional information. For example, information on a packet transmitting the unique number or information on the transmission time of the packet transmitting the unique number can be used together with the unique number to generate the public trust bit. Furthermore, the public trust bit can be constructed using the unique number together with other information, and is not limited to the above-mentioned embodiment.

[0154] Also, by way of example, the public trust field can be generated using a variety of conventional encryption algorithms, including both symmetric and asymmetric key algorithms, and is not limited to the above-described embodiments.

[0155] For example, referring to FIG. 18, the public trust check may be performed through open trust bits. The public trust packet may include at least one of a header, information data, a public trust field, and a CRC. When a terminal receives the public trust packet, the terminal performs a CRC check and can use the received information based on the CRC. If the transmitting terminal generates the public trust field using the ID of the receiving terminal, only the terminal having the corresponding ID among the terminals receiving the public trust packet can determine the reliability of the packet. As another example, if the transmitting terminal generates the public trust field using the ID of the transmitting terminal, the reliability of the public trust field can only be checked by a specific distributed terminal having the authority and function of trust check. In this case, a specific distributed terminal having the authority and function of trust check can check the reliability by itself using the unique number and public trust bit of the received information, or can transmit the unique number and public trust bit of the received information to a trust check system and receive the reliability result.

[0156] As a specific example, referring to FIG. 19, as described above, a vehicle serving as a terminal of a wireless distributed communication system can transmit its own accident information via a public trusted packet through distributed communication. As an example, a distributed road unit can receive the above information. Also, as an example, another terminal of the wireless distributed communication system can also receive the above information, and the above embodiment is not limited to the above. Thereafter, the other terminal can transmit information necessary for trust testing, such as received information including the unique number of the malfunctioning vehicle and the time of reception of the information, to a trust testing system. Thereafter, the trust testing system can calculate a public trust bit using the unique number, the time of reception, and the received information bit. Therefore, the trust testing system can judge the public information included in the public trust bit and provide trust accordingly. Also, as an example, the above trust can be applied to other terminals as well as vehicles, and is not limited to the above embodiment.

[0157] As another example, the above-mentioned public trust bit can be used when monitoring illegal vehicles (e.g., drones). In this case, whether or not a vehicle is illegal can be determined by first checking the validity of the unique number of the received unique number, as described above, and then confirming the reliability of the information using the public trust bit. That is, if the checked number is not a registered unique number, or if the checked public trust field does not match the trust field value generated by the inspection system from a pre-stored value, the vehicle can be determined to be illegal.

[0158] As another example, if a distributed terminal does not use its address value as its unique number, it must further transmit its unique number to check the public trust field. However, this requires unnecessary resources, so mobile terminals such as vehicles and drones must set their unique number as their distributed communication address. As another example, in ship distributed communication such as AIS, a unique number called MMSI can be used as its address value, and the same operation as described above can be performed.

[0159] For example, many electronic and electrical products can be connected to an integrated terminal such as a smart device. However, the process of connecting an integrated terminal such as a smart device to an object can be complicated. For example, a wireless interface must be determined for the smart device and the object to be connected to each other. This can be primarily achieved through Wi-Fi or Bluetooth. For example, the smart device must search for an application for the object and install the application. The smart device can then run the application and wait until the application recognizes the object before connecting and controlling the object. Once the application recognizes the object, the smart device user must control the smart device (e.g., the user must thoroughly read the object's manual and then press the object's terminal button multiple times). The smart device user must also perform additional operations taking into account the object's characteristics and surrounding circumstances. This requires the smart device user to perform many steps, potentially reducing usage efficiency.

[0160] As another example, a smart device can control an object after connecting via WiFi or Bluetooth. In other words, a user of the smart device must manually connect via WiFi or Bluetooth. In consideration of the above, a method for a smart device to automatically recognize and connect to an object to provide a service may be needed, and this will be described.

[0161] For example, in order for a mobile device to instantly recognize and connect to surrounding objects and receive services from them, the device and the objects must communicate directly. In this case, the device can communicate directly with the objects in various ways. For example, the device can communicate directly using conventional Wi-Fi or Bluetooth.

[0162] Further, as an example, based on the above and Reference 1 (Korean Patent Application No. 10-2017-0026778, Accession No. 1-1-2017-0207822-47, Collision Avoidance Method in a Synchronous Wireless Communication System, Korea), a terminal may directly communicate with an object through distributed communication using a contention scheme. For example, the terminal and the object may have a common communication modem, and the terminal may search for the object based on the common communication modem. Further, as an example, based on the above and Reference 3 (Korean Patent Application No. 10-2018-0014682, Accession No. 1-1-2018-0131792-95, Service Method Using Multiple Channels in a Synchronous TDMA System, Korea), an object may be searched for through distributed communication. In this case, the terminal may search for the object through a slot and a channel based on the above. Further, as an example, hereinafter, a terminal recognizing an object may mean that the terminal has completed the advance preparations required for receiving a service from the object. That is, if the terminal communicates with and installs a suitable driver or program to control the thing, the terminal can recognize the thing.

[0163] More specifically, for a terminal to immediately recognize a corresponding object, the terminal needs to wirelessly receive a driver file, program file, or program installation file for controlling the object directly from the object. However, an object cannot directly provide the driver or program required to control itself wirelessly. For example, for an object to wirelessly provide a driver or program for controlling itself, a large-capacity semiconductor memory and a means for wireless communication may be required. That is, existing objects do not have the above-described configuration and therefore cannot directly provide information about the driver or program wirelessly. However, for example, the object may also include the above-described configuration in consideration of the cost of memory and a wireless communication modem. That is, an object may have a modem for wireless communication and may have built-in information required to recognize the object (e.g., a driver file, program file, program installation file). In this case, if a terminal requests the file from the object via wireless communication, the object may provide the file via wireless communication.

[0164] Specifically, referring to FIG. 20(a), in the related art, a terminal may access an item for which a service is to be provided (S2011). At this time, the terminal may check information about the item (S2012). For example, the information about the item may be at least one of a product name, type, and model name, and is not limited to the above-described embodiment. As an example, the terminal may recognize information about the item based on information input by a user. That is, the user may access the item and check the model name. Then, the terminal may receive information about the item (e.g., driver files, program files, program installation files) via a communication network (e.g., an Internet app store or an Internet webpage) (S2013). As an example, the terminal user may search for an application or an installation file for the model and receive related information (S2014). Then, the terminal may download and install the application or installation file (S2015). At this time, the terminal may check the operation and manual of the item to recognize the item and control the item. That is, multiple steps, such as those described above, may be required.

[0165] For example, if an object stores object-related information and wireless communication is possible, the terminal may search for the object (S2021) and receive information about the object (e.g., a driver file, a program file, or a program installation file) (S2022). That is, the object may have a file stored in its memory for recognizing and controlling the object and provide the file to the terminal. For example, referring to FIG. 21, the terminal and the object may include a common communication modem and a configuration for controlling the common communication modem. The object may also include a control device for providing the file stored therein. Here, the stored file may be an information file for the object, such as a driver file, a program file, or a program installation file for controlling the object, as described above.

[0166] For example, the driver file may provide a driver required by a basic program or an OS installed on the terminal. When the driver is installed on the terminal, the terminal can receive services for the relevant item from the existing program. As a specific example, referring to FIG. 22, when a remote control basic program is installed on the terminal, the terminal can receive a driver from an air conditioner. The terminal can then search for nearby items (S2211) and select the air conditioner from the search results. After selecting the air conditioner, the terminal can download and install the driver, which can then be automatically recognized (S2212). The terminal can then control the air conditioner using the remote control basic program and the driver (S2213). While the above-described embodiment has been described based on an air conditioner, this is merely for convenience of explanation and is not limited to the above-described embodiment. That is, the present invention may be similarly applied to other items and is not limited to the above-described embodiment.

[0167] Next, if the terminal does not have a related program installed, the terminal can wirelessly download a program file or program installation file from the object and then install it. For example, referring to FIG. 22(b), a drone can be considered as the terminal. However, this is merely an example and the same applies to other objects. In this case, the drone can have a built-in program for controlling the drone. In this case, the terminal can wirelessly download the program for controlling the drone directly from the drone. Specifically, the terminal can search for a drone as a nearby object (S2221). At this time, the terminal can directly download the program from the drone, install it, and automatically recognize it (S2222). The terminal can then select and control the drone (S2223). For example, the terminal and the drone can include a common modem. Also, for example, if a general-purpose drone control terminal is available, the general-purpose control terminal can easily download an installation file from the drone to control it.

[0168] For example, when a terminal automatically recognizes and controls an object, the terminal may first wirelessly search for surrounding objects. When searching for surrounding objects, the terminal may select an object to connect to from the searched objects. The terminal may receive information about the object (e.g., driver files, program files, program installation files) from the selected object. For example, the object may broadcast information about the object, and the terminal may recognize the object using the broadcast information.

[0169] Further, as an example, a wake-up tone channel can be used based on the above and Reference 5 (Korean Patent Application No. 10-2018-0021100, Accession No. 1-1-2018-0187211-36, Terminal Operation Method Using Tone Channel in Synchronous Time Division Multiple Access System, Korea). For example, it is efficient for a battery-equipped object to operate with low power. For example, the above-mentioned object can be awakened based on a wake tone signal from a sleep state (sleep mode). In this case, the wake-up tone channel may refer to a tone channel for waking an object among the tone channels as described above. That is, it is possible to consider a case where a tone channel is used to awaken an object. In this case, an awakened object can broadcast its information on a predetermined wireless channel or check whether a packet transmitted to it exists. In this case, if an awakened object broadcasts its information, the terminal can receive the broadcast information and recognize the object.

[0170] For example, referring to FIG. 23, a terminal may transmit a wake-up tone (S2311). At this time, as described above, the terminal may transmit the wake-up tone to an entity via a wake-up tone channel, and the entity may be awakened based on this. When the entity is awakened, the entity may broadcast information about the entity over a wireless channel (S2312). At this time, the information about the entity may be the information described above. Thereafter, the terminal may receive the broadcast information about the entity to acquire the information about the entity (S2313).

[0171] As another example, after transmitting a wake-up tone, a terminal may transmit a packet in which its own address is set as the source address and the address of the awakened entity is set as the destination address. If the destination address of the received packet matches its own address, the awakened entity may transmit a response packet for the received packet to the searching terminal. The response packet includes information about the entity, allowing the terminal to obtain the information about the entity. For example, referring to FIG. 4(b), a terminal may transmit a wake-up tone over a wake-up tone channel (S2321). The terminal may transmit a packet in which its own address is set as the source address and the address of the awakened terminal is set as the destination address (S2322). The entity may then receive a packet in which its own address matches the destination address (S2323). The entity may then transmit a response packet for the received packet to the terminal (S2324). Thereafter, the terminal can obtain information about the event through the response packet and operate as described above (S2325).

[0172] For example, when a terminal searches for an object based on the above, the terminal may search for multiple objects. In this case, other objects may wake up in addition to the object the terminal is searching for, broadcast their own information for a predetermined time, and perform an operation to check for packets to be transmitted to them. Therefore, objects that the terminal does not intend to control may unnecessarily consume battery power. For example, when using a wake-up tone channel as disclosed in the above and Reference 5 (Korean Patent Application No. 10-2018-0021100, Terminal Operation Method Using Tone Channel in Synchronous Time Division Multiple Access System), a tone slot pattern can be used to awaken only desired objects. In Reference 5, the tone slot pattern can refer to transmitting information on a contention substitute channel, i.e., in subslots other than the 0th subslot of the contention tone channel. Here, the 0th subslot is used for slot clearing. However, as described above, the 0th subslot does not need to be excluded from the wake-up tone channel. Therefore, in the present invention, a tone slot pattern can be formed using all subslots including subslot 0 on a wake-up tone channel rather than a contention tone channel. As such, the tone slot pattern can be transmitted via a contention tone channel disclosed in Reference 7 (Korean Patent Application No. 10-2018-0027675, Accession No. 1-1-2018-0236883-25, Method for Efficient Tone Channel Use in a Wireless Distributed Communication System, Korea), a wake-up tone channel disclosed in Reference 5, or a tone channel in which meanings are assigned to slots and subslots disclosed in Reference 5, and is not limited to the above-described embodiment. In other words, when transmitting a tone channel to automatically recognize an object, it is possible to recognize only a specific object, and is not limited to the above-described embodiment.

[0173] Specifically, a terminal can transmit a wake-up tone and transmit a signal based on a tone slot pattern. As an example, referring to FIG. 24(a), the wake-up tone signal can be continuously transmitted during a one-second frame. However, the wake-up tone signal can be transmitted in other ways and is not limited to the above embodiment. In this case, the terminal can transmit a tone slot pattern after transmitting the wake-up tone signal. In this case, an entity can receive a further tone slot pattern after receiving the wake-up tone signal. An entity is awakened only if the tone slot pattern after the wake-up tone signal is the tone slot pattern associated with it, and can broadcast information about itself or receive a packet from the terminal.

[0174] As a specific example, after transmitting a wake-up tone signal, the terminal may transmit a tone slot pattern associated with an air conditioner as an object. In this case, multiple objects may receive the wake-up tone transmitted by the terminal, but only the air conditioner having the same tone slot pattern among the multiple objects may be awakened and communicate with the terminal. That is, the air conditioner may broadcast air conditioner information or receive a packet from the terminal.

[0175] For example, referring to FIG. 24(b), the terminal may transmit a tone slot pattern associated with the air conditioner after transmitting a wake-up tone signal (S2411). Then, the air conditioner may check the tone slot pattern received after the wake-up tone (S2412). If the tone slot pattern matches the air conditioner's pattern, the air conditioner may be awakened and broadcast air conditioner information or check whether a packet is received (S2413). As another example, a TV, which is a peripheral device, may operate as shown in FIG. 24(c). The terminal may transmit a tone slot pattern associated with the air conditioner after transmitting a wake-up tone signal (S2421). Then, the TV may check the tone slot pattern received after the wake-up tone (S2422). Since the TV's pattern does not match the tone slot pattern, the TV may remain asleep. That is, the terminal may transmit a tone slot pattern for identifying the device after transmitting a wake-up tone signal. At this time, since there may be multiple things around the terminal, the terminal can identify a specific thing through the tone slot pattern.

[0176] As another example, even if the terminal acquires information related to an object and pre-installs a driver or program, it can use the wake-up tone signal and tone slot pattern to wake up and control the object. For example, the terminal may need additional information through direct communication with the object. Specifically, the terminal may not always provide a service through the object, so it needs to indicate whether it is active for the service. For example, a user of the terminal may control the terminal to perform direct communication with the object. In this case, the terminal may operate as described above based on the wake-up tone signal and tone slot pattern.

[0177] As another example, the terminal may automatically select an object to be controlled from among multiple objects. The terminal may automatically select an object based on a setting in a higher layer (a program or application). As another example, the terminal may have a pre-configured program, and may automatically select an object based on the pre-configured program. As another example, if there is a machine that automatically feeds animals or waters plants, the terminal program may automatically select and control the object periodically. Specifically, referring to FIG. 25, the terminal may be configured to periodically execute a program (S2511). As an example, in FIG. 25, a feeding program may automatically perform a feeding operation, but this is merely an example and is not limited to the above-described embodiment. Thereafter, the terminal may transmit a wake-up tone via a wake-up tone channel (S2512). That is, the terminal program may periodically transition the object to an awake state using the wake-up tone. As another example, a tone slot pattern may be transmitted based on the above-described period, thereby waking the object at the above-described period. That is, the tone slot pattern can be set taking into account the period, and the object can be awakened based on the preset period through the tone slot pattern taking into account the period information, and this is not limited to the above-described embodiment. Then, the object that receives the wake-up tone signal can be awakened and broadcast its own information or check whether its own packet is present (S2513). That is, the feeding machine and surrounding objects can be awakened and broadcast their own information. At this time, the terminal can select the object (or objects) after receiving the broadcasted object information (S2514). That is, the terminal can select the feeding machine after receiving the broadcasted object information. The terminal can then control the object (or objects) through direct communication (S2515). That is, the terminal can transmit feeding instructions to the feeding machine and control the object to operate based on the instructions.

[0178] As another example, a terminal may wirelessly download a file from an object and then use the file to perform an operation required for recognition. For example, the operation required for recognition may primarily involve installing a driver or program suitable for controlling the object on the terminal. Here, the terminal may recognize and control the object using a downloaded and installed program, but downloading a driver is more efficient than downloading an entire program. In other words, a general-purpose program is installed on the terminal, and the downloaded and installed driver can be applied to the program to perform control. For example, if a general-purpose remote control program is installed on the terminal, an air conditioner driver can be downloaded from an air conditioner to operate the air conditioner, and a TV driver can be downloaded from a TV to operate the TV.

[0179] Also, for example, when operating based on the above, authentication or password setting may be required during the process of recognizing an object. For example, security and other issues may arise if an object is controlled by another unauthenticated terminal. Therefore, when a terminal requests an object to download a file stored in the object, the object may request a password from the terminal. Alternatively, the terminal may wirelessly transmit a password in a packet for controlling the object, and the object may permit control only if it is authenticated by inspecting the password in the packet. In other words, the terminal and the object may perform an authentication procedure, and only once authentication is complete may the terminal be granted control of the object. For example, all terminals may recognize an object, but only specific authenticated terminals may control the object.

[0180] For example, a method for maintaining security may involve transmitting the password itself, but stronger security can be maintained by scrambling the information sent using the password with a PN code. For example, the security format may be changed. Specifically, if a user sets an initial password after purchasing something, a security or authentication method other than a password may be required.

[0181] For example, whether or not to allow an object to be controlled may be determined based on the reception power or path loss of a signal received by the object. More specifically, the object may calculate the reception power or path loss of the received signal. The object may be allowed to control the object only if the calculated reception power is greater than a threshold or the path loss is less than a threshold. That is, the object may allow a terminal that is a certain distance away or close to the object to control it using a signal. For example, the range of a wireless distributed communication system may be set wider than the area in which the terminal or object is located. However, a terminal user or system may determine the usage range by granting control authority only to signals within a certain distance. For example, if a resident of another house tries to control the TV in my house, the reception power of the control signal arriving at the TV is lower than a threshold and the TV cannot be controlled. In this case, a user who purchased the TV as the user of the object may set a reception power threshold or path loss threshold for the TV to prevent control by others. For example, referring to FIG. 26(a), the object may receive a control signal from a terminal (S2611). At this time, the entity can calculate the received power or path loss of the received control signal (S2612). If the received power is greater than a threshold or the path loss is less than a threshold (S2613), the entity can determine that the terminal is an adjacent terminal and allow control (S2614). Also, as an example, if the received power is less than a threshold or the path loss is greater than a threshold (S2613), the entity can not allow control (S2615).

[0182] As another example, control of an object may be performed based on a terminal ID. For example, a terminal ID may be registered in an object. That is, when an object registers the ID of a terminal that can control the object, the terminal may transmit a wireless packet containing its own ID to the object. The object may then use the ID information in the received packet to determine whether the packet is from an authenticated terminal and may grant control based on this. For example, referring to FIG. 26(b), a controllable terminal ID may be registered in the object (S2621). When the object receives a control signal (S2622), the object may determine whether the ID included in the control signal matches the registered ID (S2623). If the control signal contains the registered ID, the object may grant control (S2624). On the other hand, if the control signal does not contain the registered ID, the object may deny control (S2625).

[0183] As another example, initial registration of an object can be considered. For example, referring to FIG. 26(c), an object may receive a control signal for the first time (S2631). For example, when a user purchases an object for the first time or when the object is used for the first time after being reset, the object may receive a control signal for the first time. Here, the object may automatically register the terminal ID included in the received control information as a control-permitted terminal registration ID (S2632). In other words, by recognizing and registering a user for the first time, user use can be made more convenient. When the object receives a control signal (S2633), the object may determine whether the ID included in the control signal matches the registered ID (S2634). If the control signal includes the registered ID, the object may permit control (S2635). On the other hand, if the control signal does not include the registered ID, the object may not permit control (S2636).

[0184] For example, the terminal can not only recognize the object but also perform additional control over the object. For example, the terminal can automatically execute a program related to the object and automatically receive and display the current state of the object on the program interface screen. This allows the terminal user to efficiently provide information and services about the object's status.

[0185] Specifically, a device can recognize and control an object once it has been recognized without downloading a file stored in the object. Specifically, referring to FIG. 27, a device can request control of a previously recognized object (S2711). That is, a user of the device can request control of a previously recognized object via the device. The device can then wirelessly search for nearby objects (S2712). If the object is present (S2713), the device can obtain control authority for the object and provide a service (S2714). On the other hand, if the object is not present (S2713), the device can provide the user with information that the service is unavailable and terminate the service (S2715). Here, the method of searching for the object can be the same as the method of searching for an object to recognize it for the first time.

[0186] As another example, information (e.g., drivers, programs) built into an object can be updated. In this case, the update requires that not only the object but also the terminal be connected. For example, the terminal can request a version of the information (e.g., drivers, programs) from the object and receive information about the version. The terminal can then use the received version information to determine whether the information needs to be updated. In this case, the terminal can receive update information for the object using a conventional communication network or another communication network. The terminal can wirelessly transmit the update information for the object to the object. The object can update and install the driver or program file transmitted from the terminal.

[0187] More specifically, referring to FIG. 28, a terminal may request version information from a peripheral object and receive the information (S2811). At this time, the terminal may check whether the received version information is the latest information (S2812). At this time, if the received information is the latest information, the terminal may terminate the update procedure. On the other hand, if the received version information is not the latest information, the terminal may transmit a driver or program to the object (S2813). For example, the terminal may receive the latest driver or program for the peripheral object from another server and transmit it to the object. The object may then update and install the transmitted driver or program into its existing file (S2814).

[0188] For example, when a terminal wirelessly searches for an object, the terminal may receive information from the object based on a specific format. The terminal may then determine the type of the object based on the received information and perform a recognition procedure for the object. For example, the terminal may perform an initial search for the object and acquire initial information about the object based on the initial search. For example, the initial information about the object may include at least one of the object's name, object type, object model name, object product number, built-in file type, available wireless communication information, the type and version of an underlying program associated with the user terminal, current product status information, and supported language information. The built-in file type may indicate a driver or program built into the object, and the available wireless communication information may refer to information about a communication means provided by the object. For example, an object may include one or more communication means, so available wireless communication information may be utilized. For example, the object's product number may be used. After the terminal installs the driver or program for the object, the product number may be automatically registered in the installed program based on the product number.

[0189] For example, files stored in each object may be created in the language of each country. In particular, when a program is installed, the program menu may be displayed in the language of that country. However, in some cases, multiple languages ​​may need to be supported. In this case, for example, a driver or program file may be stored in the object for each supported language. As another example, a driver or program file may be created and stored in the object in a common manner regardless of language, and language-related files may be further stored in the object for each supported language. This effectively reduces memory size. In other words, when a terminal receives a driver or program for an object, the terminal may also download language-related files to support each language. This allows the user to view the program in the desired language.

[0190] As another example, referring to FIG. 29, a method for a terminal to recognize an object based on the above can be provided. For example, in the past, a terminal had to access an object for which it wanted to receive a service (S2911) and confirm the product name, type, and modem name for the object (S2912). Then, the terminal can receive a file for the object via a communication network (e.g., an Internet application store or a web page) (S2913). In this case, for example, the terminal can search for the file via the communication network (S2914), download the target file or application, and then install it (S2915). Then, the terminal can check the operation and manual for recognizing the object (S2916) and access the object through authentication such as logging in (S2917). Then, the terminal can register the product number of the object (S2918) and perform additional tasks for product configuration (S2919).

[0191] On the other hand, when automatically recognizing an object as described above, the terminal may operate according to FIG. 29(b). In this case, the terminal may search for nearby objects (S2921) and select an object from the selected objects (S2922). In this case, the terminal may automatically install related files (S2923) and automatically recognize the object and register the product number, as described above (S2924). Also, as an example, the terminal may perform additional tasks for product configuration, as described above (S2925).

[0192] Specifically, Reference 1 uses a collision contention scheme for a synchronous wireless distributed communication system. According to the present invention, the distributed communication system may be a TDMA system and may use slots, as described above. The scheme of Reference 1 may also refer to the use of slots as shown in FIG. 30(a). This is as described above. For example, the main channel is a data channel through which data is transmitted, and may include broadcast slots or use slots as disclosed in Reference 3 (Korean Patent Application No. 10-2018-0014682, Service Method Using Multiple Channels in a Synchronous TDMA System). For example, the subchannel primarily refers to a tone channel, hereinafter referred to as a contention tone channel. For example, contention may refer to TDMA slot allocation contention using a contention substitute channel, as described above and in Reference 1, and the mapping between the data channel and the contention tone channel is as described above. In this case, as an example, slot clearing can be performed and information can be transmitted based on Reference 5 (Korean Patent Application No. 10-2018-0021100, Terminal operation method using tone channel in synchronous time division multiple access system) and Reference 6 (Korean Patent Application No. 10-2018-0021101, Terminal operation control method in wireless distributed communication system), and the following can also operate based on the above.

[0193] Reference 3 also discloses a configuration for a slot map, which can be used below. As an example, a slot map may refer to a map that creates a list of slots that each terminal can allocate from the entire slot resources. As an example, as described above, in a synchronous TDMA distributed communication environment, the frame length can be set to 1 second and the slot length can be set to 2 ms. That is, 500 slots can exist per second. As an example, a slot can be divided into subslots. The following description is based on the case where one slot has 40 subslots, but is not limited to this. As an example, Figure 30(b) may be a frame structure based on the above.

[0194] At this time, Figure 31 is a diagram illustrating a method for a drone to perform collision avoidance. While Figure 31 illustrates a drone as an example, the drone may be a terminal or other device. That is, while Figure 31 is described based on a drone for convenience of explanation, it may also be applied to other terminals or devices to which a wireless distributed communication system is applied. Therefore, although the following description of related content will be collectively referred to as a terminal, this may be a drone or other device of a wireless distributed communication system and is not limited to the above-described embodiment.

[0195] Referring to Figure 31, consider the case where there are terminals A, B, C, and D moving from the east, west, south, and north to point X. In this case, each terminal can assign its own unique registration ID, position, direction of travel, etc. to a broadcast slot and broadcast based on this. Therefore, each terminal can receive the position and direction of other terminals, thereby predicting collisions in advance.

[0196] As an example, terminal A may allocate a usage slot using a contention tone channel and transmit a route modification request packet to terminals B, C, and D in the allocated usage slot. In this case, FIG. 32(a) may show the above packet. Referring to FIG. 32(a), the packet header may be 0x02, which may indicate multiple route modification requests from designated terminals. Also, as an example, the source address may represent a 32-bit unique ID of terminal A. Also, the number of destination addresses may represent three, if it is "0x3." As an example, the destination address in FIG. 31 may represent the terminal unique IDs of terminals B, C, and D, respectively. Also, the data may include modified route information for terminals B, C, and D. Also, as an example, FIG. 32(b) may be the configuration of a packet when terminals A, B, C, and D are grouped under one group ID. For example, in the above case, only one destination address may be required.

[0197] At this time, as described above, terminals B, C, and D that have received the point-to-multipoint packet can transmit ACK responses to terminal A in response to the packet.

[0198] More specifically, referring to FIG. 33, one terminal may receive allocation of use slot resources for point-to-multipoint communication using a contention proxy channel (S3310). Then, the terminal transmits a point-to-multipoint communication packet using the allocated use slot resources (S3320). As a result, other terminals may receive the point-to-multipoint packet (S3330). At this time, as an example, each terminal that receives the point-to-multipoint packet as another terminal may transmit an ACK response to the packet (S3340). Then, the point-to-multipoint packet transmitting terminal may receive packet ACK responses from each terminal (S3350). At this time, other terminals that receive the communication packet based on the point-to-multipoint method may respond. As an example, in the above-mentioned FIG. 31, the other terminals may be terminals B, C, and D.

[0199] More specifically, first, each terminal can allocate a slot through contention, and transmit an ACK response to one terminal (drone A in FIG. 31) in the allocated slot. However, in the above case, additional slot resources need to be allocated.

[0200] Second, based on Reference 2, each terminal (each drone in FIG. 31) can transmit an ACK response to the above-mentioned used slot in the broadcast slot it occupies. However, as an example, some terminals may not periodically broadcast their information, so this method can be applied to terminals that are assigned a broadcast slot and perform periodic transmission. As an example, referring to FIG. 34(a), terminal A can transmit a one-to-many packet in the third used slot of frame 5. Then, terminals B, C, and D can transmit ACKs for the above-mentioned packet in the 20th, 30th, and 40th broadcast slots of frame 5, respectively. However, this is merely an example and is not limited to the above-mentioned embodiment. Also, in FIG. 34(a), the broadcast slot exists in the broadcast channel and the used slot exists in the used channel. However, in a mixed channel, the broadcast slot and the used slot may exist in the same channel. In this case, based on the above, it is possible to utilize pre-defined slot resources without allocating additional slot resources. Also, as an example, multiple ACK responses to the used slots can be transmitted simultaneously in the broadcast slot, rather than just one. As an example, referring to FIG. 34(b), multiple ACKs can be transmitted simultaneously. Here, consider a case where terminal A is assigned three slots, slots 3, 6, and 9. However, this is merely an example and is not limited to the above-described embodiment. Also, as an example, referring to FIG. 34(b), the broadcast slot number of terminal B is 20, and ACK responses can include those for slots 3, 6, and 9. Also, as an example, the broadcast slot number of terminal C is 40, and ACK responses can include those for slots 3, 6, and 9. Also, as an example, the broadcast slot number of terminal D is 50, and ACK responses can include those for slots 3, 6, and 9. However, the above-described method is merely an example and is not limited to the above-described embodiment.

[0201] As another example, an ACK response can be transmitted by a method of transmitting information together with a slot clearing signal on a contention tone channel as described in Reference 5. That is, each terminal receiving a point-to-multipoint packet can transmit a tone signal in a sub-slot of a contention tone slot resource that is mapped to a used slot resource allocated and continuously used by a terminal transmitting the point-to-multipoint packet. In this case, the tone signal can include an ACK response to the point-to-multipoint packet.

[0202] As an example, referring to FIG. 35a, when one available slot is allocated for point-to-multipoint communication, the ACK response can be transmitted as a tone signal. Also, as an example, referring to FIG. 35b, when multiple available slots are allocated for point-to-multipoint communication, the ACK response can be transmitted as a tone signal. Also, as an example, referring to FIG. 35c, when an available slot group is allocated for point-to-multipoint communication based on Reference Document 2, the ACK response can be transmitted as a tone signal. Also, as an example, referring to FIG. 35d, when one available slot is allocated for point-to-multipoint communication, the ACK response can be transmitted as a tone signal with a pre-assigned sub-slot number. As an example, the above explanation can be used mainly when the destination address is a group ID.

[0203] Also, as an example, referring to Figure 35e, when one available slot is allocated for point-to-multipoint communication, a NACK response can be transmitted as a tone signal. In this case, for example, the above-described operation can be performed in an environment where there are few information transmission errors and therefore no need to send an ACK. That is, if there is no particular error, another ACK is not transmitted, and if an error occurs as a negative response, a NACK signal can be transmitted. Also, as an example, referring to Figure 35f, when multiple available slots are allocated for point-to-multipoint communication, a NACK response can be transmitted as a tone signal.

[0204] As a specific example, in FIG. 35a, terminal A can transmit a point-to-multipoint packet in the third occupied slot of frame 5. At this time, the terminal can transmit an ACK in the second tone slot of frame 6. Terminals B, C, and D can transmit ACKs in sub-slots 2, 3, and 4, respectively. Here, there are various methods for transmitting an ACK from sub-slot 2. For example, ACKs can be transmitted in the order in which the destination addresses are included in the point-to-multipoint packets, but this is not limiting.

[0205] As a specific example, FIG. 35b shows a case in which terminal A allocates three slots, numbered 3, 6, and 9, for point-to-multipoint communication. In this case, terminal A can transmit a point-to-multipoint communication packet in the third used slot of frame 5. Then, the terminal can transmit an ACK in the fifth tone slot of frame 5. For example, terminals B, C, and D may transmit ACKs in subslots 2, 3, and 4, respectively, as shown in FIG. 35a. Furthermore, a response to a point-to-multipoint packet transmitted in the sixth used slot of frame 5 can be transmitted in the eighth tone slot of frame 5. Furthermore, a response to a point-to-multipoint packet transmitted in the ninth used slot of frame 5 can be transmitted in the second tone slot of frame 6.

[0206] As a specific example, FIG. 35c shows a case where terminal A allocates a slot group for point-to-multipoint communication. Here, the slot group is a multiple of 50. That is, one slot group may consist of a total of 10 slots, numbered 3, 53, 103, 153, ..., 453. Terminal A may transmit a point-to-multipoint communication packet in the third used slot of frame 5. Then, the terminal may transmit an ACK in the 52nd tone slot of frame 5. In this case, terminals B, C, and D may transmit ACKs in subslots 2, 3, and 4, respectively, as shown in FIG. 6a, as described above. A response to the point-to-multipoint packet transmitted in the 53rd used slot of frame 5 may be transmitted in the 102nd tone slot of frame 5. However, this is merely an example and is not limited to the above-described embodiment.

[0207] As a specific example, in FIG. 35d, terminal A can transmit a point-to-multipoint packet in the third occupied slot of frame 5. At this time, the terminal can transmit an ACK in the second tone slot of frame 6. As an example, terminals B, C, and D can transmit ACKs in subslots 5, 8, and 13, respectively. Here, the subslot number in which each terminal transmits an ACK may be specified in advance or dynamically, and is not limited to the above-mentioned embodiment. That is, a response subslot may be preset for each terminal. Also, as an example, when a terminal transmits a point-to-multipoint communication packet, the packet may include information on the subslot number to which each terminal responds. That is, a terminal receiving a point-to-multipoint communication packet can respond based on the subslot number included in the packet.

[0208] As a specific example, in FIG. 35e, terminal A can transmit a point-to-multipoint packet in the third occupied slot of frame 5. At this time, the terminal can transmit a NACK in the second subslot of the second tone slot of frame 6. For example, considering an environment where errors rarely occur, as described above, a NACK can be transmitted only when a reception error occurs. For example, in FIG. 35e, terminals B and C can transmit a NACK. Even if two terminals simultaneously transmit NACK tone signals, terminal A can detect the presence of a NACK. The subslot numbers in which each terminal transmits a NACK can be specified in advance or dynamically. Multiple terminals can be assigned the same subslot number for transmitting a NACK. For example, in a point-to-multipoint file transmission, if even one terminal does not receive a packet, the entire packet must be retransmitted. However, since the point-to-multipoint packet transmitting terminal does not know which terminal sent the NACK, it always retransmits the packet upon receiving the NACK. Therefore, when using the method of Figure 6b, in order to ensure efficient point-to-multipoint communication, each point-to-multipoint packet receiving terminal measures its own point-to-multipoint packet reception error rate, and if a high error rate is measured, it automatically withdraws from the point-to-multipoint communication, thereby ensuring the efficiency of the point-to-multipoint communication.

[0209] Referring to FIG. 35f, terminal A can transmit a point-to-multipoint packet in slots 3, 6, and 9 of frame 5. In this case, terminals can transmit NACKs for slots 3, 6, and 9 of frame 5 in subslots 2, 3, and 4 of tone slot 2 of frame 6. As described above, if no reception error occurs, terminal A does not need to transmit a NACK. Even if multiple terminals simultaneously transmit NACK tone signals, terminal A can detect the presence of a NACK. Consider a case where multiple terminals are assigned the same subslot number for NACK transmission. The subslot number may represent a NACK for the point-to-multipoint packet transmitted in slots 3, 6, and 9. This NACK response method is efficient when NACKs are received occasionally in an environment where packet reception errors rarely occur. In this case, terminals do not need to transmit a NACK every time an error occurs in each packet, but can efficiently transmit NACKs while receiving multiple packets.

[0210] Also, as an example, in Figures 35a, 35b, 35c, 35d, 35e, and 35f, a terminal transmitting an ACK or NACK response may transmit a tone in subslot 0 to perform group slot clearing. As an example, the hidden node problem in point-to-multipoint communication may be considered. In this case, all terminals involved in point-to-multipoint communication may transmit slot clearing tones in tone slots mapped to the usage slots in which the point-to-multipoint communication is performed. This allows the entire point-to-multipoint communication group to use the allocated slots without collisions, which may be referred to as "group slot clearing" hereinafter. In this case, as an example, even when the entire group performs group slot clearing, collisions may occur over the usage slot resources allocated for point-to-multipoint communication. For example, the configuration of terminals participating in point-to-multipoint communication may continuously change depending on the communication environment. In other words, one of the slots allocated for the current point-to-multipoint communication may be a slot where collisions occur for a terminal newly participating in the point-to-multipoint communication. Also, as an example, if a moving terminal approaches the vicinity of the point-to-multipoint communication group while a terminal in the point-to-multipoint communication group is stopped, a slot resource collision may occur with that terminal.

[0211] As an example, referring to FIG. 36, a case may be considered in which terminals A, B, C, and D are assigned slots 3, 6, and 9 for communication. However, this is merely an example and is not limited to the above-described embodiment. In this case, a case may be considered in which terminal E, using slot 3, accesses terminal C near terminal C. For example, in the above-described case, resource collision may occur in slot 3. Therefore, to resolve the resource collision issue, collision information needs to be provided to terminal A, which transmits a point-to-multipoint communication packet. Here, as an example, a method for detecting collision may be to check whether or not a tone is received in subslots other than those used for slot clearing and ACK / NACK responses. For example, if a received tone is present as a result of the check, it may be determined that the above-described collision has occurred. In this case, the terminals may transmit a predetermined tone signal in a tone slot for slot clearing in order to check for collision. For example, referring to FIG. 37(a), a tone signal for collision avoidance may be transmitted along with a slot clearing signal in a plurality of subslots preceding the 0th subslot. For example, the above-described method may operate based on, but is not limited to, Reference 4. Also, as an example, referring to FIG. 37(b), a subslot for collision detection can be allocated in the middle, and is not limited to the above-described embodiment. Meanwhile, as an example, an entire group can transmit a tone signal for collision detection in the same subslot, which will be referred to as a "group tone" hereinafter. For example, the section in which the group tone signal is transmitted may be referred to as a "group tone section." As an example, each terminal in a one-to-many group can transmit a group tone in the group tone section. Furthermore, if a tone signal of a subslot that does not belong to the group tone is detected in the group tone section, this can be considered a collision. In this case, a case in which collision is permitted can be considered, and reference 3 can be referred to for specific details.

[0212] In addition, for example, if a collision occurs in a slot used for point-to-multipoint communication, the terminal can notify the point-to-multipoint packet transmitting terminal of the presence or absence of a collision, i.e., the slot number where the collision occurred. For convenience of explanation, the above and following descriptions refer to the terminal as a terminal. This can be applied to a terminal or other devices as well. That is, the term terminal is used only for convenience of explanation, and the same can be applied to a terminal or other devices.

[0213] As an example, in consideration of the above, the terminal can allocate a use slot and perform point-to-point communication with a point-to-multipoint packet transmitting terminal (e.g., terminal A). That is, the terminal can notify whether there is a collision based on the above. As another example, the terminal can broadcast information about the collision slot in the broadcast slot in which it broadcasts its own information. This allows the point-to-multipoint packet transmitting terminal (e.g., terminal A) to check whether there is a collision and the collision slot.

[0214] For example, terminal A may receive information about the slot in which the collision occurred from terminal C. Terminal A may then perform the procedures necessary for point-to-multipoint communication. At this time, terminal A may determine whether or not to allow the collision, as described above. For example, terminal A may assign a slot to replace the slot in which the collision occurred. Alternatively, terminal A may exclude the slot in which the collision occurred from point-to-multipoint communication, as described in Reference 3 above.

[0215] However, as an example, a conflict of use slots may occur from the time terminal A first allocates use slots for point-to-multipoint communication. In this case, if a conflict of slot resources occurs from the start of communication, it may be difficult to carry out smooth communication. Taking the above points into consideration, when allocating use slots for point-to-multipoint communication, it is possible to allocate use slots that do not cause conflicts.

[0216] As an example, as described above, slot map information broadcast by each terminal can be used to allocate collision-free available slots. In this case, when each terminal transmits its information in the broadcast slot, it can include its slot map information in the broadcast slot. Therefore, terminal A can create a "group available slot map" that can be used by all terminals in the entire group based on the slot maps received from each terminal. Terminal A can also allocate available slots belonging to the group available slot map through contention on the contention proxy channel. Based on the above, a point-to-multipoint packet transmitted by terminal A can be transmitted to terminals B, C, and D without resource collision.

[0217] More specifically, referring to FIG. 38, for convenience of explanation, the number of slots may be 10 instead of 500. However, this is merely for convenience of explanation, and the same applies to cases where the number of slots is different. In this case, as an example, the slot maps of terminals A, B, C, and D may be "0110011100," "0110011110," "0010100100," and "0111011111," respectively. However, this slot map is also merely an example and is not limited to the above embodiment. In this case, a group valid slot map can be derived by combining the above slot maps, and the group valid slot map may be "0010000100." In other words, terminal A can be assigned the third and eighth available slots to perform point-to-multipoint communication without collision.

[0218] The following describes an operation based on a case where terminal A does not receive an ACK response to a point-to-multipoint packet. As mentioned above, the following description is based on a terminal. However, this is merely for convenience of explanation and the present invention can be applied to other terminals or devices as well, and is not limited to the above-described embodiment. As an example, if a terminal that transmitted a point-to-multipoint packet does not receive an ACK response from all terminals that receive the point-to-multipoint packet, the terminal can retransmit the point-to-multipoint packet to all terminals in the use slots allocated for point-to-multipoint communication. As an example, referring to FIG. 39(a), terminal A can retransmit the point-to-multipoint packet because it received ACKs from terminals B and C but did not receive an ACK from terminal D. As another example, after allocating use slots for point-to-point communication with terminals that have not received an ACK response via contention, it can retransmit the point-to-multipoint packet only to terminals that have not received an ACK response in the allocated use slots. As an example, referring to FIG. 39(b), if terminal A does not receive an ACK only from terminal D, terminal A can transmit the point-to-multipoint packet in the use slots allocated only to terminal D.

[0219] However, as an example, a case may be considered in which an ACK response is not continuously received from a certain terminal. In this case, as an example, a case may be considered in which terminal C is too far away from terminal A. For example, referring to FIG. 40, terminal C may be at the boundary of the communication distance of terminal A or may move outside the boundary. In this case, terminal A may not continuously receive an ACK response for the point-to-multipoint packet from terminal C. Therefore, it may be efficient for terminal A to exclude terminal C from the point-to-multipoint communication. In this case, as an example, a method for excluding terminal C from the point-to-multipoint communication may be performed by deleting the ID of terminal C from the destination address included in the point-to-multipoint packet. Also, as an example, if the destination address is a group ID, terminal A may exclude terminal C from its own group list. Also, as an example, terminal A may independently ignore the presence or absence of an ACK response from terminal C, and the above-described embodiment is not limited thereto.

[0220] That is, for efficient point-to-multipoint communication, terminal A calculates the ACK response rate from each terminal, and if the ACK response rate is below a preset threshold, it can exclude that terminal from the point-to-multipoint communication. This makes it possible to omit unnecessary operations for terminals that are difficult to receive ACK responses from.

[0221] Also, as an example, a dynamic group may be formed in the above-mentioned point-to-many communication. For example, when point-to-many communication is performed, a case where a preset group terminal is designated may be considered. Also, as an example, when point-to-many communication is performed, a case where a group terminal dynamically joins may be considered. For example, a case where point-to-many communication is performed to avoid collisions between terminals may be considered. As an example, the following description will be based on a case where terminal A dynamically forms a group after allocating slot resources to be used for point-to-many communication using a contention proxy channel, but the present invention is not limited to this. Also, as an example, the following description will be based on a terminal, but the present invention can be similarly applied to a terminal or other devices and is not limited to the above-mentioned embodiment.

[0222] For example, terminal A may induce joining of a point-to-multipoint communication group without specifying it itself. That is, terminal A may allocate a broadcast slot using a contention proxy channel and broadcast point-to-multipoint communication group information in the allocated broadcast slot. In this case, for example, the point-to-multipoint communication group broadcast information may include at least one of an allocated slot number, a group joining requirement, a group slot clearing execution method, an ACK response method, data encryption information, and sequence use / non-use information. For example, the point-to-multipoint communication group broadcast information may further include other information related to point-to-multipoint communication and is not limited to the above-described embodiment. In this case, when a group is dynamically allocated as described above, the group joining requirement may be set to a terminal located in a collision-prone area in a specified time domain. More specifically, the group slot clearing execution method may refer to whether clearing is performed and the execution method described above. In this case, the ACK response method may use any of the above-described methods. In addition, the data encryption information may refer to information on an encryption method applied to point-to-multipoint communication packets after joining the group. In addition, whether a sequence is used may refer to whether a sequence is added to packets from the start to the end of point-to-multipoint communication. In this case, for example, a terminal receiving the broadcasted point-to-multipoint communication group information can check the above-mentioned group joining requirements and determine whether or not to join the group. For example, if the terminal decides to join the group based on the above-mentioned information, it can transmit a packet requesting joining the point-to-multipoint communication group to the terminal broadcasting the point-to-multipoint communication group information. In this case, the join request may be transmitted to terminal A using its own occupied broadcast slot. Also, for example, the terminal can transmit the request by separately allocating a use slot through contention and transmitting a point-to-point packet.

[0223] In this case, terminal A, which has received the point-to-multipoint communication group join request, can determine whether to accept the request. For example, if terminal A accepts the join request, terminal A can join the terminal to the point-to-multipoint communication group. In this case, terminal A does not need to notify the joined terminal whether or not it approves the join. Terminal A can also transmit a point-to-multipoint packet by including the address of the joined terminal in the destination address. Furthermore, for example, terminal A can first transmit a packet indicating whether or not to join to the joining terminal before transmitting the point-to-multipoint packet. In this case, the packet indicating whether or not to join may include, in addition to join approval information, at least one of an ACK response method, an ACK response subslot number, a joining number, whether or not to perform group slot clearing, whether or not to encrypt data, and whether or not to use a sequence. However, the packet indicating whether or not to join may further include other information and is not limited to the above embodiment. Here, the ACK response subslot number may be a subslot number used when sending an ACK response using a tone signal. Furthermore, the subscriber number may be a number assigned to the subscribed terminal by the terminal in charge of one-to-multipoint communication, and is not limited to the above-described embodiment.

[0224] 41 is a diagram illustrating a method for a terminal to join a dynamic group based on the above. For example, referring to FIG. 41, one terminal may receive allocation of slot resources for point-to-multipoint communication using a contention proxy channel (S4110). Then, one terminal may be allocated a broadcast slot and broadcast point-to-multipoint communication group information (S4120). At this time, each terminal that receives the point-to-multipoint communication group information may transmit a request to join the communication group to the terminal (S4130). Then, the group information broadcasting terminal that receives the group join request may join the requesting terminal to the point-to-multipoint communication group and perform point-to-multipoint communication (S4140).

[0225] As another example, a method for terminating the point-to-many communication can be considered. For example, terminal A can suspend transmission of the point-to-many communication packet. That is, the broadcasting entity can suspend the broadcast directly. As another example, terminal A can transmit a point-to-many communication termination packet to notify other terminals of the termination of the point-to-many communication. As another example, terminal A can notify other terminals that the point-to-many communication group is no longer valid by no longer broadcasting the point-to-many communication group information. In this case, before terminating the broadcast of the point-to-many communication group information, terminal A can once again broadcast information that the point-to-many communication group is being terminated. That is, as described above, the point-to-many communication can be terminated more stably.

[0226] Also, as an example, slot resources for point-to-multipoint communication may be allocated in advance. For example, instead of one terminal allocating slot resources for point-to-multipoint communication using a contention proxy channel, the distributed communication system may allocate slot resources for point-to-multipoint communication in advance. In this case, the slot resources for point-to-multipoint communication may be allocated by including the slot resource information in advance in a communication parameter file that is built into a distributed communication terminal and is periodically updated, as disclosed in Reference 6 (Korean Patent Application No. 10-2018-0021101, Terminal Operation Control Method in a Wireless Distributed Communication System).

[0227] Specifically, Reference 1 uses a collision contention scheme for a synchronous wireless distributed communication system. According to the present invention, the distributed communication system may be a TDMA system and may use slots, as described above. The scheme of Reference 1 may also refer to the use of slots as shown in FIG. 42(a), as described above. For example, the main channel is a data channel through which data is transmitted, and may include broadcast slots or use slots as disclosed in Reference 3 (Korean Patent Application No. 10-2018-0014682, "Service Method Using Multiple Channels in a Synchronous TDMA System"). For example, the subchannel mainly refers to a tone channel, hereinafter referred to as a contention tone channel. For example, contention may refer to TDMA slot allocation contention using a contention substitute channel as described above and in Reference 1, and the mapping between the data channel and the contention tone channel is as described above. In this case, as an example, slot clearing can be performed and information can be transmitted based on Reference 5 (Korean Patent Application No. 10-2018-0021100, Terminal operation method using tone channel in synchronous time division multiple access system) and Reference 5, and the following can also operate based on the above.

[0228] Reference 3 also discloses a configuration for a slot map, which can be used in the following. For example, a slot map refers to a map that creates a list of slots that each terminal can allocate from the entire slot resources. As an example, as described above, in a synchronous TDMA distributed communication environment, the frame length can be set to 1 second and the slot length can be set to 2 ms. That is, 500 slots can exist per second. As an example, a slot can be divided into subslots. The following description is based on the case where one slot has 40 subslots, but is not limited to this. As an example, Figure 42(b) may be a frame structure based on the above.

[0229] At this time, Figure 43 is a diagram illustrating a method for a drone to perform collision avoidance. As an example, while Figure 43 illustrates a drone, the drone may be a terminal or other device. That is, for convenience of explanation, Figure 43 is described based on a drone, but it may also be applied to other terminals or devices to which a wireless distributed communication system is applied. Therefore, although the related content will be collectively referred to as a terminal below, this may be a drone or other device of a wireless distributed communication system, and is not limited to the above-described embodiment.

[0230] As an example, referring to FIG. 43, terminals A, B, C, and D may perform many-to-many communication. Consider terminals A, B, C, and D moving from east, west, south, and north to point X in FIG. 43. Each terminal may be assigned a broadcast slot for its unique registration ID, location, and direction of travel, and broadcast the information in the assigned broadcast slot. As described above, each terminal can receive the location and direction of other terminals and avoid collisions based on the information. As an example, the terminals may perform many-to-many communication. For example, the terminals may be the drones described above. If the terminals are drones, many-to-many communication may be performed for purposes such as searching for missing persons or group flights, but is not limited to the above-described embodiment.

[0231] Also, for example, a terminal performing many-to-many communication may refer to a case where the entity performing the one-to-many communication changes continuously. More specifically, rather than terminal A always sending a one-to-many packet and terminals B, C, and D responding to it, it may refer to a case where one of terminals A, B, C, and D transmits a one-to-many packet and another terminal responds to it. That is, the terminal transmitting the one-to-many packet in the many-to-many communication may change continuously. In this case, for example, whether or not there is a response in the many-to-many communication varies depending on the situation, which will be described later. The many-to-many communication may be performed based on the one-to-many communication. That is, the one-to-many communication may be considered a special case where there is only one terminal transmitting the many-to-many packet in the many-to-many communication, and is not limited to the above-described embodiment.

[0232] As another example, a slot resource for performing many-to-many communication may be required in a synchronous wireless distributed communication system. In this case, the wireless distributed communication system may allocate a predetermined slot as the many-to-many communication slot resource. As another example, the above-mentioned resource may be allocated as the many-to-many communication slot resource by a slot determined in advance based on Reference 6 (Korean Patent Application No. 10-2018-0021101, "Operation Control Method of Terminals in a Wireless Distributed Communication System"). As an example, the resource may be designated from a communication parameter file that is built into and updated in the distributed terminal disclosed in Reference 6. As another example, the many-to-many communication slot resource may be allocated to terminals performing many-to-many communication via contention proxy channels with different frequencies. In this case, all terminals in the many-to-many group must perform group slot clearing in the assigned many-to-many slots. Thereafter, the terminals in the many-to-many group may transmit many-to-many packets in the assigned many-to-many slots. In this case, each terminal in the many-to-many group must dynamically reallocate one of the allocated many-to-many slots to its own slot using a contention proxy channel with a different frequency. When one of the many-to-many slots is allocated through contention based on the above, the terminal to which the slot has been dynamically reallocated can transmit a many-to-many communication packet in the allocated slot. More specifically, referring to FIG. 44, slot resources for many-to-many communication may be allocated (S4410). Then, a terminal in the many-to-many group may be allocated one of the allocated many-to-many slots using a contention proxy channel with a different frequency (S4420). Then, the terminal may transmit a many-to-many communication packet using the allocated slot resource (S4430).

[0233] As another example, slots for many-to-many communication can be dynamically allocated. In this case, slots for many-to-many communication can be allocated to slots where resource collisions do not occur. For example, each terminal can broadcast a slot map. In this case, as described above, slots are allocated based on slot map information broadcast by the terminal, and collisions can be prevented based on this. In addition, when each terminal transmits its information in a broadcast slot, the terminal can transmit its slot map information by including it in the broadcast slot. In this case, for example, terminal A can create a "group valid slot map" that can be used by all terminals in the entire group based on the slot maps received from each terminal. In this case, slots belonging to the group valid slot map can be allocated through contention on a contention proxy channel. Based on the above, a many-to-many packet transmitted by terminal A can be transmitted to other terminals, i.e., terminals B, C, and D, without resource collisions.

[0234] Also, as an example, referring to FIG. 45, a group valid slot map can be set. For convenience of explanation, in FIG. 45, the number of slots is set to 10, but this is merely an example and is not limited to the above-described embodiment. That is, the present invention can be applied to cases where the number of slots is different. In this case, for example, referring to FIG. 45, the slot maps of terminals A, B, C, and D can be "0110011100," "0110011110," "0010100100," and "0111011111," respectively. In the above case, the group valid slot map can be "0010000100." That is, terminal A can be assigned slots 3 and 8, and can allocate many-to-many communication resources without collision.

[0235] Also, for example, resources may be dynamically allocated. After dynamically allocating slots, group slot clearing may be performed. When performing point-to-point communication based on Reference 1, slot clearing may be used to solve the hidden node problem. Hereinafter, taking into account the hidden node problem, all terminals involved in many-to-many communication may transmit slot clearing tones in tone slots mapped to the slots in which the many-to-many communication is performed. As described above, the entire many-to-many communication group can use the allocated slots without collisions. For example, the above operation is hereinafter referred to as "group slot clearing." For example, referring to FIG. 5, group slot clearing may be performed. For example, the many-to-many slots may be three slots, numbered 3, 53, and 453. Clearing may be performed in tone slots preceding the allocated slots. This allows resources to be used without collisions.

[0236] Also, as an example, FIG. 47 is a diagram illustrating a many-to-many packet. For example, the many-to-many packet in FIG. 47 may be similar to a one-to-many packet. At this time, since one-to-many communication can be a special case of many-to-many communication as described above, the packet can be configured in the same way. Many-to-many communication can be performed through the above-described packet. At this time, referring to FIG. 47(a), for example, the packet header can be 0x02, which can indicate multiple route modification requests from designated terminals. In this case, the source address can represent a 32-bit unique ID of terminal A. Also, the number of destination addresses can be 0x3, which can indicate three. In this case, the destination addresses can represent terminal unique IDs of terminals B, C, and D, respectively. Also, the data can include modified route information for terminals B, C, and D. Also, referring to FIG. 47(b), for example, a packet configuration can be shown when terminals A, B, C, and D are grouped under one group ID. At this time, for example, the destination address can require only the many-to-many communication group ID. That is, the destination address can be specified by the group ID alone. In this case, as an example, the many-to-many communication group ID can be set in advance in the system. Also, for example, the many-to-many communication group ID can be arbitrarily assigned by a terminal that has assigned a many-to-many slot, and is not limited to the above-described embodiment. In this case, if the many-to-many communication group ID is arbitrarily assigned, each terminal can join the many-to-many communication group for many-to-many communication. In this case, a procedure for each terminal to join may be required.

[0237] As another example, a terminal that receives a many-to-many communication packet may transmit a response to the packet. In this case, if the terminal is a drone as described above, a response may be required even when a many-to-many packet is transmitted. However, as an example, if a wireless group chat is performed by the terminal, a response to the many-to-many packet may not be required. In this case, it is efficient to manage a sequence, which will be described later. In addition, as another example, if the terminal is a vehicle, a conditional response may be performed in the many-to-many communication used in vehicle communication.

[0238] For example, in order to avoid collisions between drones, drone A in Figure 43 can transmit a route modification request by sending the packet in Figure 47(a) to drones B, C, and D. In this case, drones B and C may notify drones that they have modified their routes, while drone D may be unable to modify its route and may choose to reduce its speed instead of modifying its route. In other words, each drone (or terminal) can transmit various types of response information taking into account the above-mentioned situations.

[0239] For example, each terminal (or drone) can transmit response information for the many-to-many packet by including a response to the many-to-many packet in the broadcast slot it occupies. For example, referring to FIG. 46, drones B, C, and D can transmit response data for the many-to-many packet sent by terminal A in use slot 3 in broadcast slots 20, 16, and 8, respectively. However, this is merely an example, and transmission can be performed through other slots. In other words, the information can be transmitted in its own broadcast slot and is not limited to the above embodiment. Also, for example, a terminal that does not periodically broadcast its own information cannot perform the operation described above.

[0240] As another example, a terminal in each many-to-many group can be assigned one of the assigned many-to-many slots as a contention proxy channel and can transmit a response packet to a many-to-many communication packet in the assigned slot. In this case, if a destination ID is set to one terminal in the many-to-many group, a point-to-point packet can be transmitted in the many-to-many slot. Also, as another example, if a destination ID is set to a many-to-many group ID, a point-to-many packet can be transmitted in the many-to-many slot. In other words, the assigned many-to-many slot can be used to transmit a point-to-many or point-to-point packet depending on the situation.

[0241] As another example, a response packet to a many-to-many communication packet can be transmitted through a general slot instead of a many-to-many slot. In this case, the general slot is allocated using a contention proxy channel, and then the response can be transmitted in the allocated slot. However, in the above case, additional resources may be required in addition to the resources used for many-to-many communication.

[0242] As another example, whether to respond to a many-to-many packet can be determined according to conditions. For example, referring to FIG. 48, terminal D can request terminals A, B, and C to transmit information about a missing person to terminal D only when they have found the missing person. However, the above is merely an example and is not limited to the above embodiment. That is, whether to respond can be triggered and transmitted based on certain conditions. Here, the assigned many-to-many slots can be slots 3, 6, 9, and 12, but this is merely an example and is not limited to the above embodiment. In this case, terminals A, B, and C can transmit a response only when certain conditions are met (e.g., when they have found the missing person), as described above.

[0243] As an example, in Figure 50(a), if no one satisfies the response condition (if all missing persons have not been found), all terminals may not respond. Also, as an example, in Figure 50(b), if terminal C satisfies the response condition (if drone C finds the missing persons), terminal C may transmit a response. At this time, terminal C may transmit a one-to-one packet using occupied slot No. 53, which does not belong to the many-to-many slots. That is, terminal C may transmit a response via a one-to-one packet. As another example, in Figure 50(c), terminal C may transmit a one-to-one packet using occupied slot No. 6, which belongs to the many-to-many slots. At this time, as an example, in Figures 50(b) and 50(c), the other terminal may always transmit an ACK in response to the response packet sent by terminal C. At this time, if terminal C does not receive an ACK, terminal C may transmit another response packet. For example, if terminal A sends a request to terminals B, C, and D to notify it of drones searching for a missing person, terminal C cannot receive the request. In this case, drone C cannot transmit information about the missing person to drone A. Therefore, drones B, C, and D must transmit ACKs in response to the many-to-many packet sent by drone A. In this case, the ACK transmission described above can be performed in various forms.

[0244] In this case, for example, a terminal can receive slot resource allocation through contention. Then, the terminal can transmit a point-to-point packet including an ACK for the many-to-many packet in the allocated slot. As another example, each terminal (or drone) can broadcast an ACK response in its own broadcast slot, thereby transmitting the ACK response.

[0245] As another example, based on Reference 5, a terminal may transmit ACK response information along with a slot clearing signal on a contention tone channel. That is, after receiving a many-to-many packet, the terminal may transmit a tone signal in a sub-slot of a contention tone slot resource that is mapped to a slot resource allocated and continuously used by a many-to-many packet transmitting terminal. In this case, the tone signal may include and transmit an ACK response to the many-to-many packet. Also, as an example, the ACK transmission method for a many-to-many packet may be the same as the ACK transmission method for a point-to-many packet. That is, as described above, point-to-many communication may be a specific state of many-to-many communication. Since many-to-many communication can be viewed as a constantly changing subject of point-to-many communication, the ACK transmission method may be the same as described above.

[0246] The following describes a method for broadcasting many-to-many group information and a method for managing the sequence of many-to-many packets, which can achieve efficient and stable many-to-many communication and ensure system stability.

[0247] For example, many-to-many group information may be broadcast. A terminal that has assigned a many-to-many slot may allocate a broadcast slot using a contention proxy channel and broadcast the many-to-many communication group information in the assigned broadcast slot. Terminals that receive the broadcast information may then request to join the many-to-many communication group. For example, this may be done in a wireless group chat or autonomous communication between drones, as described above. The many-to-many communication group information broadcast in the assigned broadcast slot may include at least one of the following: a purpose of the created group, a group ID, group password setting information, a channel used for the many-to-many communication group, assigned slot information, transmission power information for this broadcast slot, a leave reception power value for this broadcast slot, a leave reception slot error rate, group clearing tone setting information, retransmission clearing subslot information, subslot-related information for the tone channel used to transmit ACK / NACK, sequence information for the many-to-many communication group, whether the broadcast slot in which the group information is broadcast is a continuous reception mode, and group valid slot map information. In addition to the above information, other information for the many-to-many communication group may also be included, and is not limited to the above-described embodiment.

[0248] Here, the purpose of the created group may refer to the service provided by the created many-to-many group. The group ID may be an ID assigned by the terminal generating the many-to-many communication group itself or assigned in advance by the system. The group password setting information may indicate whether a password is required when joining the group. For example, the leave reception power value of the broadcast slot may be the reception power value of the broadcast slot in which the joined terminal must leave. The leave reception error rate may be the reception error rate value of the broadcast slot in which the terminal must leave. The group clearing tone setting information may indicate whether group clearing is performed and the sub-slot position of the tone. The retransmission clearing sub-slot information may indicate whether clearing used for retransmission is performed and the sub-slot position of the tone. The sub-slot-related information of the tone channel used to transmit ACK / NACK may indicate at least one of whether ACK is required for many-to-many communication, whether a conditional ACK must be transmitted, and sub-slot number information when transmitting ACK. The sequence information of the many-to-many communication group may indicate whether a sequence is used in many-to-many communication and, if so, the current sequence number. In addition, whether or not a broadcast slot in which group information is broadcast is continuously received may mean whether terminals joining the many-to-many communication group must continuously receive this broadcast slot, and the group valid slot map information may be slot information that all terminals joining the group can use.

[0249] A terminal receiving the broadcast slot can check various information regarding the many-to-many communication. A terminal attempting to join the many-to-many communication group can then allocate a usage slot using a contention proxy channel. The terminal can transmit a one-to-one packet requesting the many-to-many communication group information broadcasting terminal to join the many-to-many communication group using the allocated usage slot. The many-to-many group generating terminal receives the request, allows the terminal to join the group, and transmits a packet once the joining is complete. For example, if the terminal's joining is rejected, the many-to-many group generating terminal can transmit a packet indicating that the joining has been rejected. For example, the joining rejection can occur based on a password mismatch or the type of terminal that cannot join. For example, the joining rejection can be set for other reasons or conditions and is not limited to the above embodiment. The joining rejection can occur for various reasons.

[0250] 51, for example, a terminal may allocate slot resources for many-to-many communication (S5110). Then, the many-to-many group management terminal may allocate a broadcast slot and broadcast many-to-many communication group information in the allocated broadcast slot (S5120). At this time, the many-to-many communication group information is as described above. Then, a terminal that has received the many-to-many communication group broadcast information may allocate a slot to use and transmit a point-to-point packet requesting joining the group (S5130). Then, the many-to-many communication group management terminal may allow or reject the terminal to join based on the request, as described above (S5140).

[0251] As a specific example, consider a case where a terminal (or drone) operates based on a many-to-many communication group. For example, terminal A (or drone A) can receive a request including slot map information of terminal B from terminal B (or drone B) that wishes to join the many-to-many communication. In this case, terminal A may be a many-to-many group management terminal. In this case, terminal A can use the slot map information of terminal B described above to check whether the currently assigned many-to-many group slots are available for terminal B. For example, if there are many-to-many group slots that cannot be used by terminal B, it is necessary to return the assigned slots and allocate other slot resources. In this case, terminal A can create a "group valid slot map" from the slot maps of terminal A and terminal B, which displays slots that can be used by both terminals. Then, terminal A can use the group valid slot map information to allocate slots that can be used by terminal A and terminal B together.

[0252] As an example, consider a case where terminal C has already joined the above-mentioned group. In this case, terminal A is the management terminal of the above-mentioned group, and therefore can know the group valid slot map information of terminals A and C in advance. When drone B joins the above-mentioned group, terminal A can update the above-mentioned group valid slot map to a group valid slot map that can be used by all of terminals A, B, and C. In other words, the group valid slot map can be updated taking into account the slot maps of all terminals included in the group. As described above, when a terminal joins a many-to-many group, the management terminal can check and assign collision-free slots.

[0253] As another example, a subscribed terminal may perform group slot clearing to solve the hidden node problem. At the same time, a collision of a many-to-many communication slot may be checked in real time. For example, a many-to-many slot allocated to avoid collisions during subscription may encounter a collision during use. In this case, a method for checking for a collision may be to check whether a tone is received in a sub-slot other than the sub-slot transmitted by the many-to-many group in a tone slot belonging to the many-to-many group. If a received tone is found as a result of the check, the terminal may recognize that a collision has occurred. For example, the terminal may transmit a tone signal in a preset manner to check for a collision in a tone slot for slot clearing.

[0254] More specifically, referring to FIG. 52(a), a tone signal for collision avoidance can be transmitted along with a slot clearing signal in multiple subslots beginning with subslot 0. For example, the above-described method may be similar to that described in Reference 5. As another example, a subslot for collision detection may be allocated in the middle, as shown in FIG. 52(b). In this case, the entire group can transmit a tone signal for collision detection in the same subslot. In this case, the above-described tone signal may be called a "group tone." However, this is merely an example and may be called by other names. Furthermore, the interval in which the group tone signal is transmitted may be called a "group tone interval." This is also merely an example and may be called by other names. As another example, each terminal in a one-to-multiple group can transmit a group tone in the group tone interval. In this case, if a tone signal of a subslot that does not belong to the group tone is detected in the group tone interval, this can be considered a collision. In other words, since only group tone signals can be transmitted in the group tone interval, the presence of other signals can be determined as a collision. In this case, for example, referring to Reference 3, even if a collision is detected, it is possible to determine whether or not to allow the collision. That is, in certain cases, the operation can be performed while allowing the collision. Also, for example, in certain cases, the operation can be performed while not allowing the collision, and is not limited to the above-described embodiment. However, for the sake of convenience, the following description will be based on the case where the collision is not allowed. That is, although the operation can be performed while allowing the collision, the following description will be based on the case where the collision is not allowed, for the sake of convenience.

[0255] As an example, as described above, terminal A in the many-to-many communication group may be a management terminal. Terminal B may be a terminal that has joined the many-to-many communication group. If terminal B detects a collision, it may transmit the slot number in which the collision occurred to terminal A managing the many-to-many group. At this time, terminal B may also transmit its current slot map to update the group valid slot map. However, in a system in which each terminal transmits its slot map information through a broadcast slot, unnecessary information may be continuously transmitted. In consideration of the above, terminal A managing the many-to-many group may exclude the slot in which the collision was reported from the many-to-many group slot resources, and may also exclude the collision slot number from the many-to-many group slot resources broadcast in the broadcast slot.

[0256] Also, as an example, the many-to-many group management terminal A can allocate another slot as the many-to-many group slot in place of the excluded slot. Terminal A can allocate any one slot in the current group valid slot map through the contention proxy channel. Also, if a collision report is received for the newly allocated slot, terminal A can repeat the slot allocation procedure.

[0257] Also, as an example, a sequence can be assigned to the many-to-many packet as described above. In this case, for example, ACK / NACK can be transmitted and received based on the sequence of the many-to-many packet described above. For example, referring to FIG. 53, the packet header in FIG. 53(a) may be 0x04, which indicates transmission of many-to-many group information with a sequence. Also, the source address may indicate a 32-bit unique ID of terminal A. Also, the destination address may be 0x33, which indicates the many-to-many group ID. Also, the sequence number is 5 bits and may have a value of "00111." However, the above settings are merely examples, and other values ​​may be set. That is, the many-to-many packet can be configured based on FIG. 53 and is not limited to the above embodiment. In this case, for example, other terminals receiving the many-to-many packet may not transmit a response. For example, the error rate of the many-to-many packet may be small. Also, for example, since packets are not always transmitted in the assigned many-to-many slots, it is not possible to determine whether a transmission was not successful or an error occurred. That is, in consideration of the above, a response is not transmitted.

[0258] However, errors may also occur in many-to-many packets. For example, referring to FIG. 13, a case can be considered in which the sequence number is composed of 5 bits and is repeated from 0 to 31 in FIG. 54a. However, this is merely an example and is not limited to the above-described embodiment. Furthermore, the assigned many-to-many slots may be four slots, numbered 10, 20, 30, and 40. In this case, for example, in FIG. 54a, terminal B may not receive the signal transmitted in slot 20 of frame 5. Therefore, the current many-to-many sequence number for terminals A, B, and D may be 7, but terminal C, which has not received packet 7, may have a current sequence number of 6. Referring to FIG. 54b, in the above situation, terminal D may transmit packet 8 of sequence 8 through slot 30 of frame 5. Terminal C may receive sequence 8 and recognize that it did not receive sequence 7. Therefore, terminal C may transmit a many-to-many packet requesting a retransmission of sequence 7 through slot 40 of frame 5. In this case, for example, the retransmission request packet may not include a sequence number. For stable many-to-many communication, the retransmission request may be assigned a higher priority than a general many-to-many packet. Hereinafter, a "retransmission clearing subslot" may be defined for retransmission. The retransmission clearing subslot may refer to prioritizing a terminal requesting a retransmission or transmitting a retransmission packet. For example, in FIG. 54c, the retransmission clearing subslot may be designated as subslot 1. However, this is merely an example and is not limited to the above embodiment. In this case, subslot 0 may be used for group clearing. Terminal C may transmit a retransmission clearing tone signal through subslot 1. Alternatively, a subslot may be randomly selected from subslots 2 to 39. For convenience of explanation, FIG. 54 illustrates the case where subslot 7 is selected. However, the present invention is not limited to this example. Terminal A may randomly select a subslot from subslots 2 to 39 to transmit packet sequence 9.For example, sub-slot 6 can be selected. In this case, terminal A selects an even faster number, but since it is already unable to win the contention in sub-slot 1, terminal C can transmit a packet requesting retransmission of sequence 7. In this case, terminals A, B, and D that receive the retransmission request can operate as follows.

[0259] As an example, terminal B, which has been transmitting sequence 7 based on the above, can be assigned slot 10 of frame 6, which is the next many-to-many slot, using the contention proxy channel. At this time, terminal B can retransmit sequence 7 using the assigned slot. At this time, terminals A, B, and D can check whether they have sent sequence 7, so terminal B can use the next many-to-many slot without contention. However, as an example, if terminal A does not receive a retransmission request, terminal A can transmit packet sequence 9 in the next many-to-many slot.

[0260] Based on the above, a "retransmission clearing sub-slot" can be set. For example, referring to Figure 54d, terminal B can transmit a retransmission clearing tone signal in sub-slot 1 to prevent terminal A from transmitting a general many-to-many packet, and retransmit sequence 7, as shown in Figure 54c.

[0261] As another example, terminals A, B, and D that have received the above-mentioned retransmission request for packet 7 can all allocate the next many-to-many slot using a contention proxy channel, and the terminal that successfully allocates the slot can retransmit packet 7 in the allocated slot. As an example, referring to FIG. 54e, terminal D can win the contention and retransmit packet 7. As another example, referring to FIG. 54f, this can be the case where subslot 1 in FIG. 54e is designated as a retransmission clearing subslot. In this case, when a packet is retransmitted, the retransmission can be performed based on the packet structure shown in FIG. 12(b) above. As an example, in FIG. 53(b), a packet header of 0x05 can mean a retransmission of some many-to-many group information with a sequence.

[0262] As another example, as shown in FIG. 54b above, if terminal C has not received packet 7 transmitted by terminal B, terminal C can transmit packet 7. The above-mentioned packet is merely an example, and the same applies to cases where packets with other numbers are transmitted. For example, referring to FIG. 55a, terminal C can transmit a packet, and terminals A, B, and D can receive the packet. Terminals A, B, and D can ignore the received packet 7 if it is a retransmission packet of the existing packet 7. However, if the packet 7 received by terminals A, B, and D is a new packet 7, terminals A, B, and D can receive packet 7 again. In the above case, terminals A, B, and D can allocate the next many-to-many slot using the contention proxy channel, and the terminal that successfully allocated the slot can transmit a packet informing that the current sequence number is 7 in the allocated slot. More specifically, referring to FIG. 55(b), terminals A, B, and D contend for the retransmission clearing subslot, and terminal D, which has successfully been allocated, can transmit a packet indicating that the current sequence number is 7. As an example, the packet can be configured based on the above-described FIG. 53(c). In this case, a packet header of 0x06 can indicate "notification of the current sequence number." The above-described packet can also include the terminal address that transmitted the packet whose sequence does not match the sequence number different from the current sequence number. Therefore, terminal C receives the above-described packet and can recognize that it transmitted an incorrect sequence based on its own terminal address. In this case, terminal C can request a retransmission of sequence 7, which it did not receive. As an example, the packet indicating that the current sequence number is 7 can be transmitted by terminal B, which originally transmitted sequence 7, without contention, and is not limited to the above-described embodiment.

[0263] Also, as an example, a method that can be used efficiently with sequences for many-to-many packets is to use an ACK tone signal or a NACK tone signal. As an example, many-to-many packets are not always transmitted in many-to-many slots. Therefore, it is necessary to send ACK / NACK taking the above situation into consideration. That is, when a many-to-many packet is received, an ACK can be transmitted. On the other hand, when a many-to-many packet is not received, a NACK can be transmitted.

[0264] More specifically, referring to FIG. 56A, the retransmission clearing subslot number may be 3, the ACK transmission subslot number may be 2, and the NACK transmission subslot number may be 1. However, this is merely an example and is not limited to the above-described embodiment. In this case, for example, terminal A may transmit a many-to-many packet with sequence 7 in slot 10. Terminal B, which has received the packet with sequence 7, may transmit an ACK in subslot 2 of tone slot 19. Also, for example, terminals C and D, which have not received the packet with sequence 7, may transmit a NACK in subslot 1 of tone slot 19. That is, each terminal may transmit a tone signal in the corresponding subslot depending on whether or not it receives a many-to-many packet. Terminal A may transmit a retransmission clearing tone signal in subslot 3. Terminal A then contends for subslots 4 through 39 and is assigned slot 20, allowing it to retransmit the packet with sequence 7 described above in that slot. That is, terminal A may retransmit the many-to-many packet.

[0265] Also, as an example, referring to FIG. 56b, operation may be performed based on a NACK tone signal. Here, the retransmission clearing subslot number may be 2, and the NACK transmission subslot number may be 1. However, the above numbers are merely an example, and other subslot numbers may be used. Consider a case where drone A transmits a many-to-many packet with sequence 7 in slot 10. If terminals C and D do not receive the packet, they can transmit NACKs in subslot 1 of the 19th tone slot. In other words, terminals that have not received the many-to-many packet can transmit NACKs in the corresponding subslot of the tone slot. Terminal A then transmits a retransmission clearing tone signal in subslot 2, contends for subslots 3 through 39, and is assigned slot 20, after which it can retransmit the packet with sequence 7 described above.

[0266] As another example, the current sequence number may be included in the broadcast slot in which many-to-many group information is transmitted. For example, consider a case where terminal A transmits a many-to-many packet of sequence 7 in slot 10. If terminal C does not receive the many-to-many packet, retransmission may be performed as described above. However, if terminal C does not receive the many-to-many packet through slots 20, 30, and 40, terminal C cannot consistently confirm that it has not received sequence 7.

[0267] As an example, referring to FIG. 57(a), the many-to-many group management terminal may be the above-mentioned terminal A. In this case, the many-to-many group management terminal A may transmit a packet including the current sequence number in the broadcast slot in which the many-to-many group information is transmitted. In this case, terminal C may recognize that it has not received the 7th sequence packet using the information broadcast by terminal A. In this case, terminal C may request retransmission of the 7th packet. In this case, the broadcast slot number may be 0, for example. However, this is merely an example, and transmission based on another number is also possible.

[0268] As another example, consider the situation described above where terminal C transmits a packet with sequence 8 in slot 40 of frame 5, but the many-to-many group management drone A does not receive it. In this case, terminal A broadcasts that the current frame number is 7 in broadcast slot 0 of frame 6. Terminal C, having received the broadcast, can transmit the packet shown in FIG. 53(c) indicating that the current sequence number is 8. Terminal A, having received the packet, can transmit a packet requesting a retransmission of sequence 8, as shown in FIG. 57(c). In this case, for example, terminal C transmits information that the current sequence number is 8 in slot 10 of frame 6 when it wins the contention to transmit the current sequence number.

[0269] As another example, to stably maintain a many-to-many group in a wireless distributed communication system, a terminal may autonomously or forcibly leave the many-to-many group. For example, when a terminal belonging to a many-to-many communication group voluntarily leaves the many-to-many communication group, the terminal allocating the many-to-many communication resources may transmit a withdrawal reception power value or a withdrawal reception slot error rate of the broadcast slot in a broadcast slot allocated for broadcasting the many-to-many communication group. In this case, the terminal satisfying the above conditions may voluntarily leave the group. That is, each terminal in the many-to-many group that receives the many-to-many communication group information broadcast slot may calculate the reception power or the withdrawal reception slot error rate of the broadcast slot. In this case, if the calculated value is smaller than the withdrawal reception power value or larger than the withdrawal reception slot error rate, the terminal may voluntarily leave the many-to-many communication group. For example, referring to FIG. 58, a withdrawal reception power value or a reception error rate may be transmitted in the many-to-many group information broadcast slot (S5810). At this time, the terminals that have received the above information can calculate the reception power or reception error rate of the corresponding broadcast slot (S5820). At this time, if the reception power measured by each terminal is lower than the withdrawal reception power, the terminals can perform withdrawal. Also, if the error rate calculated by each terminal is higher than the withdrawal reception error rate, the terminals can perform withdrawal (S5830). That is, the terminals can continuously receive condition information for maintaining the group via broadcast and can decide whether to leave depending on whether the value is satisfied.

[0270] In this case, when a terminal leaves the group, the terminal can allocate one of the above-mentioned many-to-many group slots using a contention proxy channel and notify the many-to-many group management terminal of its own withdrawal in the allocated slot. In this case, the management terminal can receive the leave request and transmit an ACK response to the leave request packet to the terminal. In addition, for example, the management terminal can transmit information regarding the leave approval by transmitting another many-to-many communication packet.

[0271] Also, as an example, if the communication connection with the many-to-many group management terminal is terminated before a withdrawal request is made, the terminal among the group terminals that received the withdrawal request can notify the many-to-many group instead. Furthermore, the terminal that received the request can transmit a response to the withdrawal by performing one-to-one communication with the withdrawing terminal. However, in order for other group terminals to know that the many-to-many group management terminal has not received the withdrawal request, the many-to-many group management terminal must broadcast the received withdrawal request information in a broadcast slot each time it receives a withdrawal request. In this case, if a terminal that has left wishes to rejoin the many-to-many group, the terminal can repeat the joining procedure as described above.

[0272] Also, as an example, a terminal may withdraw from a group by terminating the many-to-many communication itself. That is, the terminal may not receive a many-to-many slot, or may not perform any many-to-many communication-related operations while receiving the slot. More specifically, the terminal may not send a response packet, an ACK / NACK, or a sequence error. That is, the terminal may not perform any operations related to the group. In this case, as an example, in the above case, the terminal may simply rejoin the group from which it left. That is, the terminal may receive a many-to-many slot again and resume performing related operations. However, packets transmitted during the withdrawal period cannot be requested for many-to-many group communication. In this case, if packet information transmitted during the withdrawal period is necessary, the terminal may receive the information by performing one-to-one communication with any one of the many-to-many group terminals.

[0273] As another example, a terminal can be forcibly removed from many-to-many communication. More specifically, the many-to-many group management terminal can measure the power or error rate of the received many-to-many packets for each terminal. At this time, if the power value or the error rate of a terminal is lower than a predetermined threshold power value, or if the error rate is higher than a predetermined threshold error rate, the management terminal can transmit information to the terminal to forcibly remove it from the group. That is, the management terminal can issue a removal command. At this time, the terminal that receives the information can remove itself from the many-to-many group, and can be forcibly removed based on the above.

[0274] FIG. 59 is a block diagram showing a terminal device.

[0275] The terminal device 100 may include a transmitter 110 that transmits a wireless signal, a receiver 120 that receives the wireless signal, and a processor 130 that controls the transmitter 110 and the receiver 120. In this case, the terminal device 100 can communicate with an external device via the transmitter 110 and the receiver 120. In this case, the external device may be another terminal device, a base station, or any other device with which communication can be performed, and is not limited to the above-described embodiment.

[0276] In this case, the configuration in which the terminal selects a slot and performs an operation as described above may be performed based on the processor 130. In addition, other configurations may also be included, and the present invention is not limited to the above configuration. In other words, the above configuration is the minimum configuration required to perform the present invention, and additional configurations may be included.

[0277] Furthermore, the terminal device of the present invention described above is a mobile terminal and is not limited to a smartphone. For example, the terminal device may be any one of a drone, a vehicle, an IoT device, and other devices. As an example, collision avoidance between drones may be performed based on the present invention. As another example, collision avoidance between vehicles may be performed based on vehicle-to-vehicle communication based on the present invention. As another example, collision avoidance between multiple devices such as home appliances may be performed, and is not limited to the above-described embodiments.

[0278] The present invention has been described above with reference to its preferred embodiments. Those skilled in the art will understand that the present invention can be embodied in various forms without departing from the essential characteristics of the present invention. Therefore, the disclosed embodiments should be considered from an illustrative rather than a restrictive perspective. The scope of the present invention is defined by the claims, not the foregoing description, and all differences within the scope of the claims should be construed as being within the scope of the present invention.

[0279] As described above, the detailed description of the preferred embodiments of the disclosed invention has been provided to enable those skilled in the art to realize and practice the present invention. Although the present invention has been described above with reference to the preferred embodiments, those skilled in the art will understand that various modifications and variations can be made to the present invention without departing from the spirit and scope of the present invention as defined in the following claims. Therefore, the present invention is not limited to the embodiments shown herein, but is intended to be accorded the widest scope consistent with the principles and novel features disclosed herein. Furthermore, while the preferred embodiments of the present specification have been illustrated and described above, the present specification is not limited to the specific embodiments described above. Various modifications can be made by those skilled in the art to which the invention pertains without departing from the gist of the present specification as defined in the claims, and these modifications should not be understood individually from the technical spirit or perspective of the present specification.

[0280] The specification explains both the product invention and the method invention, and the descriptions of both inventions can be applied supplementarily as necessary.

[0281] Furthermore, the present invention has been described with reference to its preferred embodiments. Those skilled in the art will understand that the present invention can be embodied in various forms without departing from the essential characteristics of the present invention. Therefore, the disclosed embodiments should be considered from an illustrative rather than a restrictive perspective. The scope of the present invention is defined by the claims, not the foregoing description, and all variations within the scope of the claims should be construed as being within the scope of the present invention. [Industrial Applicability]

[0282] The present invention can be applied not only to wireless distributed communication systems but also to other systems in the same manner, and is not limited to the above-described embodiments.

Claims

1. 1. A method performed by a receiving terminal for packet authenticity checking in a distributed communication system, comprising: receiving a packet from a packet sending terminal, the packet including identification information identifying the packet sending terminal or receiving terminal and a public trust field; determining whether the public trust field was generated based on the identity of the receiving terminal or the identity of the packet sending terminal; verifying the authenticity of the packet by comparing the public trust field with a pre-stored trust value corresponding to the identity; If the public trust field is generated based on the identity of the receiving terminal, the receiving terminal confirms the authenticity of the packet only if the identity in the received packet matches the identity of the receiving terminal; When the public trust field is generated based on the identification information of the packet transmitting terminal, the receiving terminal confirms the authenticity of the packet only if the receiving terminal has authority information indicating a trust confirmation authority stored in advance; A method comprising:

2. The public trust field is generated using at least one of identification information identifying the packet sending terminal and a sending time. The method of claim 1.

3. the public trust field is generated using at least one of the identification information that identifies the receiving terminal and information data of the packet; The method of claim 1.

4. The step of checking the authenticity of the packet includes: sending verification information, including identification information identifying the packet sending terminal and the public trust field, to an authentication server configured to verify the authenticity of the packet; the authentication server confirming authenticity of the packet based on the verification information; receiving an authentication result from the authentication server indicating whether the packet can be trusted based on the verification information; The method of claim 1 , comprising:

5. the public trust field is generated by at least one of a symmetric key algorithm and an asymmetric key algorithm; The method of claim 1.

6. The packet includes a header including sending information and receiving information, information data including communication content, the public reliability field, and a CRC (cyclic redundancy check). The method of claim 1.

7. A receiving terminal for checking the authenticity of a packet in a distributed communication system, comprising: a transmitter / receiver; a processor operatively connected to the transceiver; Equipped with The processor: receiving a packet from a packet sending terminal, the packet including identification information identifying the packet sending terminal or the packet receiving terminal and a public trust field; determining whether the public trust field was generated based on the identity of the receiving terminal or the identity of the packet sending terminal; verifying the authenticity of the packet by comparing the public trust field with a pre-stored trust value corresponding to the identity; If the public trust field is generated based on the identity of the receiving terminal, the receiving terminal confirms the authenticity of the packet only if the identity in the received packet matches the identity of the receiving terminal; If the public trust field is generated based on the identification information of the packet transmitting terminal, the receiving terminal confirms the authenticity of the packet only if the receiving terminal has authority information indicating a trust confirmation authority stored in advance. a receiving terminal configured to:

8. The public trust field is generated using at least one of identification information identifying the packet sending terminal and a sending time.

8. A receiving terminal according to claim 7.

9. the public trust field is generated using at least one of the identification information that identifies the receiving terminal and information data of the packet; 8. A receiving terminal according to claim 7.

10. The processor may transmit to an authentication server configured to check the authenticity of the packet: transmitting verification information including identification information identifying the packet transmitting terminal and the public trust field; the authentication server confirms the authenticity of the packet based on the verification information; receiving, from the authentication server, an authentication result indicating whether the packet is trustworthy based on the verification information; 10. The receiving terminal according to claim 9, configured to:

11. the public trust field is generated by at least one of a symmetric key algorithm and an asymmetric key algorithm; 8. A receiving terminal according to claim 7.

12. The packet includes a header including sending information and receiving information, information data including communication content, the public reliability field, and a CRC (cyclic redundancy check).

8. A receiving terminal according to claim 7.

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