Communication device, communication method, communication program, transmission device, and communication system

Abstract

A communication device includes: an acquisition unit configured to acquire first information for communication that has already used the first frequency band from a second frequency band different from the first frequency band, the first frequency band being an unlicensed frequency band capable of mixing multiple communication methods, and a communication control unit configured to control communication of a predetermined communication method that has already used the first frequency band based on the first information.

Description

Technical Field

[0001] The present disclosure relates to a communication device, a communication method, a communication program, a transmitting device, and a communication system. Background Art

[0002] Various wireless communication technologies are being developed to effectively use wireless resources. For example, in recent years, the development of low-power wide-area (LPWA) communication technology has become active.

[0003] [Citation List]

[0004] [Patent Document]

[0005] [PTL 1]JP 6259550 B Summary of the Invention

[0006] [Technical Issues]

[0007] Efficient use of radio wave resources is not always possible using existing technologies alone. For example, in unlicensed frequency bands, multiple communication standards can coexist. However, when multiple communication devices using different communication standards communicate freely, there is a concern that communication errors due to communication conflicts, deteriorating communication quality, and the like may frequently occur, making efficient use of radio wave resources impossible.

[0008] Therefore, the present disclosure proposes a communication device, a communication method, a communication program, a transmission device, and a communication system that can achieve efficient use of radio wave resources.

[0009] [Problem Solution]

[0010] In order to solve the above problems, according to a form of communication device disclosed herein, includes an acquisition unit, which is configured to acquire first information for communication that has already used the first frequency band from a second frequency band different from the first frequency band, and the first frequency band is an unlicensed frequency band that can mix multiple communication modes; and a communication control unit, which is configured to control the communication of a predetermined communication mode that has already used the first frequency band based on the first information. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a diagram illustrating an overview of the communication system of the first embodiment.

[0012] Figure 2 is a diagram illustrating terms used in the embodiments.

[0013] Figure 3 is a diagram illustrating a configuration example of a communication system according to Embodiment 1.

[0014] Figure 4 is a diagram illustrating a configuration example of a server device according to Embodiment 1.

[0015] Figure 5 is a diagram illustrating a configuration example of a base station device according to Embodiment 1.

[0016] Figure 6 is a diagram illustrating a configuration example of a broadcast station device according to Embodiment 1.

[0017] Figure 7 is a diagram illustrating a specific example of the configuration of a broadcast station device.

[0018] Figure 8 is a diagram illustrating a configuration example of a terminal device according to Embodiment 1.

[0019] Figure 9 is a diagram illustrating a specific example of the configuration of a terminal device.

[0020] Figure 10 is a diagram illustrating the frequency spectrum of broadcast waves transmitted by broadcast station equipment.

[0021] Figure 11 is a diagram illustrating an overview of the operation of the communication system 1 .

[0022] Figure 12 is a flowchart illustrating an example of broadcast processing according to Embodiment 1.

[0023] Figure 13 This diagram illustrates how different diffusion codes or code multiplexing can be used to partition the regions.

[0024] Figure 14 is a flowchart illustrating an example of a transmission process according to Embodiment 1.

[0025] Figure 15 This is a diagram illustrating Problem 1 of Example 2.

[0026] Figure 16 This is a diagram illustrating Problem 2 of Example 2.

[0027] Figure 17 This is a diagram illustrating Problem 3 of Example 2.

[0028] Figure 18 This is a diagram illustrating Problem 4 of Example 2.

[0029] Figure 19 is a diagram illustrating a configuration example of a communication system according to Embodiment 2.

[0030] Figure 20 is a diagram illustrating a configuration example of a control information transmitter according to Embodiment 2.

[0031] Figure 21 is a diagram illustrating the configuration of a subframe generated by a control information transmitter.

[0032] Figure 22 : is a diagram illustrating the frequency spectrum of the transmission wave.

[0033] Figure 23 is a diagram illustrating a configuration example of an LPWA transmitting terminal according to Embodiment 2.

[0034] Figure 24 is a diagram illustrating a configuration example of an LPWA receiver according to Embodiment 2.

[0035] Figure 25 is a diagram illustrating a configuration example of a communication system according to Embodiment 3.

[0036] Figure 26 is a diagram illustrating a configuration example of a control information transmitter according to Embodiment 3.

[0037] Figure 27 is a diagram illustrating a configuration example of a virtual satellite signal creating device.

[0038] Figure 28 is a diagram illustrating a configuration example of a communication system according to Embodiment 4.

[0039] Figure 29 : is a diagram illustrating the frequency spectrum of the transmission wave.

[0040] Figure 30 is a diagram illustrating a configuration example of a control information transmitter according to Embodiment 4.

[0041] Figure 31 is a diagram illustrating a configuration example of an LPWA transmitting terminal according to Embodiment 4.

[0042] Figure 32 This is a diagram illustrating measuring the position of a terminal device using radio waves of a broadcast station device.

[0043] Figure 33 This is a diagram illustrating measuring the position of a terminal device using radio waves of a broadcast station device. DETAILED DESCRIPTION

[0044] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In the following embodiments, the same parts are marked with the same reference numerals and their repeated descriptions are omitted.

[0045] In addition, in this specification and the accompanying drawings, multiple components having substantially the same functional configuration may be distinguished by adding different numbers or letters after the same reference numerals. For example, multiple components having substantially the same functional configuration may be distinguished as needed, such as in terminal devices 401, 402, and 403. Furthermore, multiple components having substantially the same functional configuration may be distinguished as needed, such as in broadcast station devices 30A, 30B, and 30C.

[0046] However, when there is no need to particularly distinguish each of a plurality of components having substantially the same functional configuration, these components are simply represented by the same symbol. For example, when there is no need to distinguish terminal devices 401, 402, and 403, these terminal devices are simply referred to as terminal device 40. Furthermore, when there is no need to distinguish broadcast station devices 30A, 30B, and 30C, these broadcast station devices are simply referred to as broadcast station device 30.

[0047] Furthermore, the present disclosure will be described according to the order of items shown below.

[0048] 1. Introduction

[0049] 1-1. Related technologies and issues

[0050] 1-2. Overview of Example 1

[0051] 1-3. Terms used in the examples

[0052] 2. Configuration of the Communication System of Example 1

[0053] 2-1. Overall configuration of the communication system

[0054] 2-2. Configuration of management devices

[0055] 2-3. Base Station Equipment Configuration

[0056] 2-4. Configuration of broadcast station equipment

[0057] 2-5. Terminal device configuration

[0058] 2-6. Frequency Band Allocation

[0059] 3. Operation of communication system

[0060] 3-1. Operation Overview

[0061] 3-2. Broadcast station main channel (virtual satellite)

[0062] 3-3. Processing flow of broadcast station equipment

[0063] 3-4. Processing flow of terminal equipment

[0064] 4. Conclusion of Example 1

[0065] 5. Example 2

[0066] 5-1. Technical Background and Objectives

[0067] 5-2. Transmission of Time Information (Related Technologies and Objectives)

[0068] 5-3. System Configuration

[0069] 5-4. Configuration of control information transmitter

[0070] 5-5. Configuration of LPWA transmitting terminal

[0071] 5-6. LPWA Receiver Configuration

[0072] 6. Example 3

[0073] 6-1. Problems and Solutions

[0074] 6-2. System Configuration

[0075] 6-3. Configuration of control information transmitter

[0076] 7. Example 4

[0077] 7-1. Overview of Example 4

[0078] 7-2. System Configuration

[0079] 7-3. Spectrum of Transmitted Waves

[0080] 7-4. Configuration of control information transmitter

[0081] 7-5. LPWA transmitter configuration

[0082] 8. Modify the example

[0083] 8-1. Modification examples of the embodiment

[0084] 8-2. Application Examples of the Embodiments

[0085] 8-3. Other communication systems

[0086] 8-4. Other modification examples

[0087] 9. Conclusion

[0088] 1. Introduction

[0089] <1-1. Related technologies and issues>

[0090] In order to effectively use the frequency band used in radio communications, standards for achieving fair communications such as transmission restrictions based on the center frequency used, the antenna power to be transmitted, the transmission frequency, carrier sensing, etc. have been defined in radio laws and standards such as the standards of the Association of Radio Industries and Businesses (ARIB). For example, assume that radio signals are transmitted and received in the 920MHz band. In Japan, the 920MHz band is a band that was opened by the Ministry of Internal Affairs and Communications of Japan in July 2011, and anyone can use the band without a license. However, according to the provisions of ARIB STD T-108, etc., the maximum continuous transmission time is limited to 4 seconds. This limitation is no exception in communications that comply with standards outside of Japan. When using a predetermined wireless communication technology, the technology must comply with national standards. The above standards basically focus on frequency, and there is room for optimization in the time direction.

[0091] The number of Internet of Things (IoT) devices is expected to exceed 40 billion by 2020, some of which are terminals performing wireless communications. Because the specific low-power radio (ARIB STD-T108) or Industrial, Scientific, and Medical (ISM) bands used for IoT do not require a license, each service provider plans, designs, and uses its own terminals for these purposes, and there is no mechanism for comprehensive communication control over these terminals. While specific low-power radios have frequency bands where transmission at 250 mW is possible, specific low-power radios are not suitable for comprehensive communication control purposes because the power is lower than that used for broadcasting (several to tens of kW) and carrier sensing is required.

[0092] Therefore, transmitting terminals based on different standards cannot cooperate with each other to transmit. When each terminal transmits randomly, congestion occurs in each communication, leading to communication errors. In particular, when a central channel is defined for transmission, such as in a specific low-power radio, transmission cannot be performed due to carrier sensing or interference waves transmitted by other standards in the receiver, resulting in poor reception performance. This trend is particularly pronounced in wireless communications with long communication distances, such as low-power wide-area (LPWA) communications.

[0093] <1-2. Overview of Example 1>

[0094] Therefore, in order to solve the above-mentioned problems, the following means (1) to (5) are provided in Embodiment 1. Figure 1 is a diagram illustrating an overview of a communication system 1 of Embodiment 1. Figure 1 An overview of Embodiment 1 is described.

[0095] (1) Using timing information sent from a broadcast station

[0096] The terminal device 40 (eg, a transmitting terminal) extracts and uses the timing information from the broadcast wave transmitted from the broadcast station device 30. Therefore, a plurality of terminal devices 40 (eg, a transmitting terminal) using different communication methods may be used. Figure 1 The terminal devices 401 to 404 in the example can cooperate with each other and achieve efficient use of wireless resources.

[0097] In this case, the terminal device 40 controls the communication already using the predetermined unlicensed band based on information (signals) obtained from a frequency band different from the predetermined unlicensed band. For example, it is assumed that the predetermined unlicensed band is a frequency band used in a specific low-power radio (for example, the 920 MHz band defined by ARIB T108). In this case, the terminal device 40 controls the communication already using the specific low-power radio (for example, the 920 MHz band) using a signal in a frequency band different from the frequency band prepared only for the specific low-power radio (for example, the VHF-high frequency band: 200 MHz band).

[0098] Typically, for this purpose (e.g., controlling terminals that communicate using a predetermined frequency band), the same frequency band (e.g., the 920 MHz band) is pre-divided and used as a dedicated frequency band (e.g., a portion of the 920 MHz band) for transmitting timing information, etc. However, the terminal device 40 of this embodiment controls the predetermined frequency band (e.g., the 920 MHz band) using a frequency band (e.g., the 200 MHz band) in addition to the predetermined frequency band (e.g., the 920 MHz band) prepared only for specific low-power radios, etc.

[0099] (2) Division of frequency bands used to transmit timing information, etc.

[0100] The broadcast station device 30 divides the allocated frequency band into a main channel and a plurality of sub-channels. The broadcast station device 30 transmits timing information using the main channel and transmits control information for controlling communication of the terminal device 40 on the sub-channels.

[0101] In this case, the broadcast station device 30 uses broadband radio for the main channel. Therefore, the broadcast station device 30 can broadcast accurate timing information.

[0102] In addition, the broadcast station device 30 uses narrowband radio for the subchannel. The broadcast station device 30 uses the subchannel to multicast control information. The control information may differ between multiple wireless schemes.

[0103] The broadcast station device 30 can change the spreading code or code multiplexing so that the broadcast waves of other broadcast stations and the broadcast waves of its own station can be separated and demodulated even at the same frequency.

[0104] (3) Narrowband allocation

[0105] Since narrowband communication is used for subchannels, the total number of channels increases. Therefore, the broadcast station device 30 allocates narrowband for each predetermined group (for example, for each communication method, for each service provider, for each communication management entity, for each model, and for each region). This allows each group to provide its own functions using the subchannel allocated to it.

[0106] (4) Using broadcast waves to control terminal devices

[0107] The broadcast station device 30 transmits control information to the terminal device 40 (e.g., IoT terminal) using broadcast waves. This makes it possible to control all terminal devices 40 (e.g., IoT terminals) using broadcast waves. For example, when communication congestion is predicted, such as in the event of a disaster, the terminal device 40 can be caused to stop transmitting radio waves.

[0108] (5) Use of virtual satellites

[0109] It is assumed that the information (signal) transmitted by the broadcast wave (e.g., the main channel) is obtained by down-converting the satellite wave (e.g., GPS wave) transmitted by a virtual satellite (e.g., a virtual Global Positioning System (GPS) satellite). Here, the virtual satellite is an ideal, completely geostationary satellite that does not actually exist. Unlike actual navigation satellites (e.g., GPS satellites), virtual satellites do not fluctuate in their orbits, so the ephemeris information used to calculate their own orbital information is fixed and unchanging.

[0110] Assume that the broadcast wave is a wave on which the signals of multiple virtual satellites have been superimposed. The signals of the virtual satellites can be generated by the broadcast station device 30. The broadcast station device 30 can change the diffusion code, etc., multiplied by each signal, making it easy to separate each signal on the receiving end. The broadcast station device 30 changes the diffusion code, etc., multiplied by the broadcast wave, making it possible for the receiving end to distinguish between multiple broadcast waves transmitted from different broadcast station devices 30. This makes it easy to separate each broadcast wave on the receiving end (for example, the terminal device 40).

[0111] <1-3. Terms used in Examples>

[0112] The overview of Embodiment 1 has been described above, and the terms used in the embodiment will be briefly described below. Figure 2 The following description of the terms is intended to help understanding the embodiments, and the meanings of the terms are not limited to those shown below.

[0113] (LPWA Radio)

[0114] LPWA radio is wireless communication that enables low-power, wide-area communication. For example, LPWA radio is a specific low-power radio or IoT radio communication that uses the Industrial, Scientific, and Medical (ISM) band. In the following description, communication using LPWA radio communication may be referred to as "LPWA communication."

[0115] (Broadcast Station)

[0116] A broadcast station is a device that transmits radio waves that can be received in a wide range (a broadcast station as equipment). In the following description, a "broadcast station" may be referred to as a "broadcast station device" or a "transmitting device."

[0117] (IoT Terminal)

[0118] An IoT terminal (endpoint) is a device that receives broadcast waves and performs transmission of LPWA radio communication in one terminal. An IoT terminal is a type of transmission device, terminal device, and / or communication device.

[0119] (IoT Gateway)

[0120] An IoT gateway (receiver) is a device that receives LPWA radio. An IoT gateway is a type of gateway, receiving device, base station device, relay device, and / or communication device.

[0121] (broadcast)

[0122] Broadcasting refers to sending the same information to an unspecified number of communication devices at the same time. For example, broadcasting refers to transmitting broadcast waves to an unspecified number of communication devices (such as IoT terminals).

[0123] (Multicast)

[0124] Multicasting refers to sending the same information simultaneously to multiple specific communication devices or a specific group of communication devices. For example, multicasting refers to transmitting broadcast waves to multiple specific communication devices (e.g., multiple IoT terminals) or a specific group of communication devices (e.g., multiple IoT terminals).

[0125] (Upload)

[0126] Uploading refers to moving (including copying and moving) data to a higher-level device (e.g., a server device) on the network. For example, uploading refers to moving data from a gateway (e.g., an IoT gateway) to a server that manages the transmission of data.

[0127] (Uplink)

[0128] Uplink refers to the upward direction of data flow. For example, uplink refers to the direction of radio wave propagation from a terminal device (e.g., an IoT terminal) to a gateway (e.g., an IoT gateway).

[0129] (Downlink)

[0130] Downlink refers to the downward direction of data flow. For example, uplink refers to the direction of radio wave propagation from a broadcast station to a terminal device (for example, an IoT terminal).

[0131] (Timing Information)

[0132] Timing information refers to information from which periodic timing can be extracted through signal processing, such as the pulse-per-second (PPS) signal of GPS. Timing information is not limited to the PPS signal of GPS and can be a signal for time synchronization or timing synchronization sent from other global navigation satellite systems (GNSS) such as GLONASS, Galileo, and Quasi-Zenith Satellite (QZSS) (hereinafter referred to as a timing signal). The concept of "timing signal" also includes the PPS signal of GPS. In addition, timing information can be information from which calendar and time data such as year, month, day, hour, minute, and second can be extracted (hereinafter referred to as time information).

[0133] (Control Information)

[0134] Control information refers to information used to instruct a terminal device to perform control regarding communications. For example, control information is information used to instruct a terminal device (e.g., an IoT terminal) to perform controls such as stopping and restarting transmission and changing the operating mode (e.g., controlling a wireless communication unit included in the terminal device).

[0135] <<2. Configuration of Communication System of Example 1>>

[0136] The following describes the terms used in this embodiment, briefly described above, and communication system 1 of Embodiment 1. Communication system 1 provides various wireless services to terminal devices 40, which communicate using a predetermined unlicensed frequency band that can accommodate multiple communication methods. For example, the predetermined unlicensed frequency band is the 920 MHz band.

[0137] The communication method used by terminal device 40 is, for example, a communication method using LPWA radio. Here, "a communication method using LPWA radio" refers to, for example, a communication method that complies with LPWA standards. Examples of LPWA standards include ELTRES, ZETA, SIGFOX, LoRaWAN, and NB-IoT. Of course, LPWA standards are not limited to these, and other LPWA standards may be used. Furthermore, the communication method used by terminal device 40 is not limited to a communication method using LPWA radio.

[0138] Furthermore, the communication standard (e.g., LPWA standard) used in the communication system 1 is not limited to one. One or more of the plurality of terminal devices 40 included in the communication system 1 may use a communication standard different from the communication standard of the other terminal devices 40 included in the communication system 1. For example, the communication standard used in the communication system 1 may be one or more of the plurality of LPWA standards. Furthermore, the communication standard used in the communication system 1 may be an LPWA standard and another communication standard different from the LPWA standard.

[0139] Hereinafter, the configuration of the communication system 1 will be described in detail.

[0140] <2-1. Overall Configuration of Communication System>

[0141] Figure 3 1 is a diagram illustrating a configuration example of a communication system 1 according to Embodiment 1. Figure 3 As shown in , the communication system 1 includes a server device 10 , a base station device 20 , a broadcast station device 30 , and a terminal device 40 .

[0142] The communication system 1 may include a plurality of server devices 10, a plurality of base station devices 20, a plurality of broadcast station devices 30, and a plurality of terminal devices 40. Figure 3 In the example of FIG, communication system 1 includes server devices 101, 102, etc. as server device 10. In addition, communication system 1 includes base station devices 201, 202, etc. as base station device 20, and broadcast station devices 301, 302, etc. as broadcast station device 30. In addition, communication system 1 includes terminal devices 401, 402, 403, etc. as terminal device 40.

[0143] Figure 3 The devices in can be considered as logical devices. That is, Figure 3 A portion of the devices shown in FIG. 4 may be implemented by a virtual machine (VM), a container, Docker, etc., and these may be implemented on physically the same hardware.

[0144] In this embodiment, the concept of communication device includes not only portable mobile devices such as mobile terminals (terminal devices), but also devices installed on structures or mobile objects. The structure or mobile object itself can be regarded as a communication device. In addition, the concept of communication device includes not only terminal devices, but also base station devices and relay devices. Communication devices are a type of processing device and information processing device. In addition, communication devices can also be referred to as transmitting devices or receiving devices.

[0145] [Server equipment]

[0146] The server device 10 is an information processing device connected to the base station device 20 and the broadcast station device 30 via a network. For example, the server device 10 is a host computer of a server for processing requests from client computers (e.g., terminal devices 40). The server device 10 can be a PC server, a mid-range server, or a mainframe server. The server device 10 is a type of communication device. The connection between the server device 10 and another communication device (e.g., base station device 20 or broadcast station device 30) can be a wired connection or a wireless connection. The server device 10 can also be referred to as a cloud server device, a local server device, a management device, a processing device, etc.

[0147] The server device 10 may be used, operated, and / or managed by various entities, such as mobile network operators (MNOs), mobile virtual network operators (MVNOs), mobile virtual network enablers (MVNEs), neutral host network (NHN) operators, enterprises, educational institutions (school corporations, local government education committees, etc.), real estate (buildings, apartments, etc.) managers, individuals, etc.

[0148] Of course, the entity that uses, operates, and / or manages server device 10 is not limited to this. Server device 10 may be installed and / or operated by a single commercial operator, or it may be installed and / or operated by a single individual. Of course, the entity that installs and operates server device 10 is not limited to this. For example, server device 10 may be jointly installed and operated by multiple commercial operators or multiple individuals. Furthermore, server device 10 may be shared equipment used by multiple commercial operators or multiple individuals. In this case, the installation and / or operation of the equipment may be performed by a third party other than the user.

[0149] Server device 10 provides predetermined communication services to terminal device 40 via base station device 20. For example, server device 10 provides execution services for information processing required by a predetermined application (hereinafter referred to as application processing) to terminal device 40 in which a predetermined application has been installed via wireless communication.

[0150] Here, the application processing performed by the server device 10 is information processing at the application layer level that is performed based on a request from a program (e.g., an application) included in the mobile device or that is performed in collaboration with the program, such as recognition processing of an object in an image. For example, the application processing performed by the server device 10 can be edge processing in edge computing. Application processing is different from processing at the physical layer, data link layer, network layer, transmission layer, session layer, and presentation layer levels in the OSI reference model. However, when including processing at the application layer level such as image recognition processing, the application processing can auxiliary include processing at the physical layer to the presentation layer level.

[0151] In the following description, information processing at the application layer level performed by the server device 10 (or the base station device 20) based on a request from a program included in the terminal device 40, or information processing at the application layer level performed by a device on the network in collaboration with a program included in the terminal device 40 may be referred to as "application processing." Furthermore, in the following description, provision of processing data of "application processing" by a device on the network to the terminal device 40, or provision of a processing function (or processing service) of "application processing" by the server device 10 or the base station device 20 to the terminal device 40 may be referred to as "provision of application processing."

[0152] [Base station equipment]

[0153] The base station device 20 is a wireless communication device that wirelessly communicates with the terminal device 40. The base station device 20 is a type of communication device. The base station device 20 is, for example, a device corresponding to an IoT gateway. The base station device 20 can be a device corresponding to a wireless base station (base station, etc.) or a wireless access point. In addition, the base station device 20 can be a wireless relay station. The base station device 20 can be an optical projection device called a remote radio head (RRH). In addition, the base station device 20 can have the functions included in the server device 10 (for example), providing application processing functions.

[0154] The wireless access technology used by the base station device 20 for wireless communication with the terminal device 40 is, for example, LPWA communication technology. Of course, the wireless access technology used by the base station device 20 is not limited to LPWA communication technology and may be another wireless access technology such as cellular communication technology or wireless LAN technology. In addition, the wireless communication used by the base station device 20 may be wireless communication using radio waves or wireless communication using infrared or visible light (optical radio).

[0155] Base station device 20 may be used, operated, and / or managed by various entities. For example, the entities are assumed to be mobile network operators (MNOs), mobile virtual network operators (MVNOs), mobile virtual communication enablers (MVNEs), neutral host network (NHN) operators, enterprises, educational institutions (school corporations, local government education boards, etc.), real estate (buildings, apartments, etc.) managers, individuals, etc.

[0156] Of course, the entity that uses, operates, and / or manages base station equipment 20 is not limited to this. Base station equipment 20 may be installed and / or operated by a commercial operator, or it may be installed and / or operated by an individual. Of course, the entity that installs and operates base station equipment 20 is not limited to this. For example, base station equipment 20 may be jointly installed and operated by multiple operators or multiple individuals. Furthermore, base station equipment 20 may be shared equipment used by multiple operators or multiple individuals. In this case, the installation and / or operation of the equipment may be performed by a third party other than the user.

[0157] The concept of base station equipment (also called base station) includes not only donor base stations but also relay base stations (called relay stations or relay station equipment). In addition, the concept of base station includes not only the structure with base station function but also the equipment installed in the structure.

[0158] Examples of structures include skyscrapers, houses, steel towers, station facilities, airport facilities, port facilities, and stadiums. The concept of structure includes not only buildings but also non-building structures such as tunnels, bridges, dams, walls, and towers, or equipment such as cranes, gates, and windmills. Furthermore, the concept of structure includes not only structures on land (in the narrow sense of the ground) or underground, but also structures on water such as docks or giant buoys, or underwater structures such as ocean observation equipment. Base station equipment may also be referred to as processing equipment or information processing equipment.

[0159] The base station device 20 may be a donor station or a relay station. In addition, the base station device 20 may be a fixed station or a mobile station. A mobile station is a wireless communication station (or broadcasting station) configured to be movable. In this case, the base station device 20 may be a device installed on a mobile body, or may be the mobile body itself. For example, a relay station device with mobility may be regarded as a base station device 20 serving as a mobile station. In addition, a device with mobility that includes the functions of a base station device (at least some functions of a base station device), such as a vehicle, a drone, or a smartphone, corresponds to the base station device 20 serving as a mobile station.

[0160] Here, the mobile object may be a mobile terminal such as a smartphone or mobile phone. In addition, the mobile object may be a mobile object that moves on the ground (ground in a narrow sense) (for example, a vehicle such as a car, bicycle, bus, truck, motorcycle, train, or linear motor vehicle), or may be a mobile object that moves underground (inside a tunnel) (for example, a subway).

[0161] In addition, the mobile body may be a mobile body that moves on water (for example, a ship such as a passenger ship, a cargo ship, or a hovercraft), or may be a mobile body that moves underwater (for example, a submersible such as a submersible, a submarine, or an unmanned submersible device).

[0162] Furthermore, a mobile object may be a mobile object that moves in the atmosphere (for example, an aircraft such as an airplane, an airship, or an unmanned aerial vehicle), or may be a mobile object that moves outside the atmosphere (for example, an artificial satellite, a spacecraft, or a space station, or an artificial celestial body such as a detection device). A mobile object that moves outside the atmosphere may also be referred to as a space mobile object.

[0163] In addition, the base station device 20 can be a ground station installed on the ground. The ground station is a ground wireless communication station or a ground broadcasting station. For example, the base station device 20 can be a base station device set on a ground structure, or it can be a base station device installed on a mobile body moving on the ground. More specifically, the base station device 20 can be an antenna installed in a structure such as a building, and a signal processing device connected to the antenna. Of course, the base station device 20 can be the structure or the mobile body itself. "Ground" refers not only to land (ground in a narrow sense), but also to ground in a broad sense, including underground, on water, and in water. The base station device 20 is not limited to a ground base station device. The base station device 20 can be a non-ground base station device (non-ground station device) that can float in the air or in space. For example, the base station device 20 can be an aircraft station device or a satellite station device.

[0164] Aircraft station equipment is a wireless communication device that can float in the atmosphere, such as an aircraft. Aircraft station equipment can be equipment installed in an aircraft, etc., or it can be the aircraft itself. The concept of aircraft includes not only heavy aircraft such as airplanes and gliders, but also light aircraft such as balloons and airships. In addition, the concept of aircraft includes rotary-wing aircraft such as helicopters or gyroplanes, as well as heavy aircraft and light aircraft. Aircraft station equipment (or the aircraft in which the aircraft station equipment is installed) can be an unmanned aircraft such as a drone.

[0165] The concept of unmanned aerial vehicles also includes unmanned aerial vehicle systems (UAS) and tethered unmanned aerial vehicle systems (tethered UAS). Furthermore, the concept of unmanned aerial vehicles includes lighter-than-air UAS (LTA) and heavier-than-air UAS (HTA). Furthermore, the concept of unmanned aerial vehicles also includes high-altitude UAS platforms (HAP).

[0166] Satellite station equipment is a wireless communication device that can float outside the atmosphere. The satellite station equipment can be a device installed on a space mobile such as an artificial satellite, or it can be the space mobile itself. The satellite used as the satellite station equipment can be any of a low earth orbit (LEO) satellite, a medium earth orbit (MEO) satellite, a geostationary orbit (GEO) satellite, and a highly elliptical orbit (HEO) satellite. Of course, the satellite station equipment can be a device installed in a low earth orbit satellite, a medium earth orbit satellite, a geostationary orbit satellite, or a highly elliptical orbit satellite.

[0167] The coverage area of ​​base station device 20 can range from a large area like a macrocell to a small area like a picocell. Of course, the coverage area of ​​base station device 20 can also be very small, such as a femtocell. Furthermore, base station device 20 may have beamforming capabilities. In this case, base station device 20 can form beams for each cell or service area.

[0168] exist Figure 3 In the example of , the base station device 20 is directly connected to the terminal device 40, but the base station device 20 may be able to communicate wirelessly with the terminal device 40 indirectly via another base station device 20 (relay device).

[0169] [Broadcast station equipment]

[0170] The broadcast station device 30 is a device that broadcasts various types of information (or various signals) to the terminal devices 40. For example, the broadcast station device 30 uses the VHF (Very High Frequency) high frequency band to broadcast various types of information (or various signals). The broadcast station device 30 is a type of transmitting device. In this embodiment, it is assumed that not only the "data" but also the "signals" transmitted from the broadcast station device 30 are "information." In this embodiment, the broadcast station is a broadcast station as equipment. Broadcast stations also include broadcast relay stations.

[0171] Here, the broadcast station device 30 may be a transmitter of a predetermined broadcast standard. For example, the broadcast station device 30 may be a DVB transmitter or an ISDB transmitter. In addition, the broadcast station device 30 may be an ATSC transmitter such as an ATSC 3.0 transmitter. In addition, the broadcast station device 30 is not limited to transmitters of these standards and may be transmitters of other broadcast standards. In addition, the broadcast station device 30 may be a transmitter according to an independent broadcast standard specifically used to transmit information (e.g., timing information or control information) so as to allow the terminal device 40 to communicate using an unlicensed frequency band.

[0172] In addition, the broadcast station device 30 can be a wireless station. For example, the broadcast station device 30 can be a wireless communication station constituting a wireless communication system such as Long Term Evolution (LTE) or New Radio (NR). In addition, the broadcast station device 30 can be a device corresponding to a wireless base station, a radio access point, or a wireless relay station. In this case, the broadcast station device 30 can be a base station or relay station for a cellular communication system such as LTE or NR. When the wireless communication station has the function of transmitting information (or signals) via broadband, the wireless communication station (e.g., base station device 20) can also be considered a broadcast station.

[0173] The broadcast waves used by the broadcast station device 30 for broadcasting are not limited to terrestrial waves. For example, the broadcast waves may be satellite waves. Satellite waves are radio waves transmitted from satellites.

[0174] Furthermore, the broadcast station device 30 may be a fixed station. In this case, the broadcast station device 30 may be a device mounted on a structure or may be the structure itself. Furthermore, the broadcast station device 30 may be a mobile station. In this case, the broadcast station device 30 may be a device mounted on a mobile object or may be the mobile object itself. Furthermore, the broadcast station device 30 may be a ground station. For example, the base station device 20 may be a broadcast station device installed on a ground structure or may be a broadcast station device mounted on a mobile object moving on the ground. Furthermore, the broadcast station device 30 may be a non-ground station. For example, the broadcast station device 30 may be an aircraft station device or a satellite station device.

[0175] [Terminal device]

[0176] Terminal device 40 is a wireless communication device that wirelessly communicates with base station device 20 or another terminal device 40. Base station device 20 is one type of communication device. Terminal device 40 is, for example, a mobile phone, a smart device (smartphone or tablet), a personal digital assistant (PDA), or a personal computer. Furthermore, terminal device 40 may be a machine-to-machine (M2M) device or an IoT device (IoT terminal).

[0177] In addition, the terminal device 40 may be able to perform LPWA communication with the base station device 20. The terminal device 40 may be a device that can only transmit or a device that can only receive. Of course, the terminal device 40 may be able to both transmit and receive. In addition, the terminal device 40 may be able to perform sidelink communication with another terminal device 40. The terminal device 40 may use automatic retransmission technologies such as hybrid ARQ (HARQ) when performing sidelink communication. The terminal device 40 may also be able to perform LPWA communication in communication (sidelink) with another terminal device 40. The wireless communication (including sidelink communication) used by the terminal device 40 may be wireless communication using radio waves, or may be wireless communication using infrared or visible light (optical radio).

[0178] In addition, the terminal device 40 can be a mobile device. Here, the mobile device is a mobile wireless communication device. In this case, the terminal device 40 can be a wireless communication device installed on a mobile body or can be the mobile body itself. For example, the terminal device 40 can be a vehicle moving on a road, such as a car, bus, truck or motorcycle, or a wireless communication device installed in a vehicle. The mobile body can be a mobile terminal, or can be a mobile body moving on land (ground in a narrow sense), underground, on water or in water. In addition, the mobile body can be a mobile body such as a drone, a helicopter, etc. that moves in the atmosphere, or can be a mobile body such as an artificial satellite that moves outside the atmosphere.

[0179] The terminal device 40 can simultaneously connect to multiple base station devices or multiple cells for communication. For example, when a base station device supports a communication area via multiple cells (e.g., pCell or sCell), carrier aggregation (CA) technology, dual connectivity (DC) technology, or multi-connectivity (MC) technology can be used to bundle the multiple cells together so that the base station device 20 and the terminal device 40 can communicate. Alternatively, the terminal device 40 and multiple base station devices 20 can communicate with each other via the cells of different base station devices 20 using coordinated multi-point transmission and reception (CoMP) technology.

[0180] The terminal device 40 does not necessarily need to be a device used directly by a person. The terminal device 40 may be a sensor installed in a machine in a factory, etc., such as a so-called machine-type communication (MTC). In addition, the terminal device 40 may be a machine-to-machine (M2M) device or an Internet of Things (IoT) device. In addition, the terminal device 40 may be a device with a relay communication function, such as represented by device-to-device (D2D) or vehicle-to-everything (V2X). In addition, the terminal device 40 may be a device called customer premises equipment (CPE) used in wireless backhaul, etc.

[0181] Hereinafter, the configuration of each device constituting the communication system 1 according to the embodiment will be described in detail. The configuration of each device shown below is only an example. The configuration of each device may be different from the following configuration.

[0182] <2-2. Server Equipment Configuration>

[0183] First, the configuration of the server device 10 will be described. Figure 4 is a diagram illustrating a configuration example of a server device 10 according to Embodiment 1. The server device 10 includes a communication unit 11 , a storage unit 12 , and a control unit 13 . Figure 4 The configuration shown in is a functional configuration, and the hardware configuration may be different from such a configuration. In addition, the functions of the server device 10 can be distributed and implemented in multiple physically separated configurations. For example, the server device 10 can be configured as multiple server devices.

[0184] The communication unit 11 is a communication interface for communicating with other devices. The communication unit 11 may be a network interface or a device connection interface. For example, the communication unit 11 may be a local area network (LAN) interface, such as a network interface card (NIC), or a USB interface configured as a universal serial bus (USB) host controller, a USB port, or the like. Furthermore, the communication unit 11 may be a wired interface or a wireless interface. The communication unit 11 serves as a communication device for the server device 10. The communication unit 11 communicates with the base station device 20 and the broadcast station device 30 under the control of the control unit 13.

[0185] The storage unit 12 is a storage device from which data can be read or written, such as a dynamic random access memory (DRAM), a static random access memory (SRAM), a flash memory, and a hard disk. The storage unit 12 serves as storage means of the server device 10.

[0186] The control unit 13 is a controller that controls each unit of the server device 10. The control unit 13 is implemented by a processor such as a central processing unit (CPU) or a microprocessor unit (MPU). For example, the control unit 13 is implemented by the processor using random access memory (RAM) or the like as a workspace to execute various programs stored in a storage device within the server device 10. The control unit 13 can be implemented by an integrated circuit such as an application-specific integrated circuit (ASIC) or a field-programmable gate array (FPGA). A CPU, MPU, ASIC, or FPGA can all be considered a controller.

[0187] <2-3. Configuration of Base Station Equipment>

[0188] Next, the configuration of base station device 20 will be described. Figure 5is a diagram illustrating a configuration example of a base station device 20 according to Embodiment 1. The base station device 20 can perform LPWA communication with the terminal device 40. The base station device 20 includes a wireless communication unit 21, a storage unit 22, a network communication unit 23, and a control unit 24. Figure 5 The configuration shown in is a functional configuration, and the hardware configuration may be different from such a configuration. In addition, the functions of the base station device 20 may be distributed and implemented in a plurality of physically separated configurations.

[0189] The wireless communication unit 21 is a signal processing unit for wirelessly communicating with another wireless communication device (e.g., terminal device 40 or another base station device 20). The wireless communication unit 21 operates under the control of the control unit 24. The wireless communication unit 21 supports one or more wireless access schemes. For example, the wireless communication unit 21 supports communication using LPWA communication.

[0190] The storage unit 22 is a storage device from which data can be read and written, such as a DRAM, an SRAM, a flash memory, and a hard disk. The storage unit 22 serves as storage means of the base station device 20.

[0191] Network communication unit 23 is a communication interface for communicating with other devices. For example, network communication unit 23 is a LAN interface. Network communication unit 23 can be a wired interface or a wireless interface. Network communication unit 23 serves as a network communication device for base station device 20. Network communication unit 23 communicates with server device 10 under the control of control unit 24.

[0192] The control unit 24 is a controller that controls each unit of the base station device 20. The control unit 24 is implemented, for example, by a processor such as a CPU or MPU. For example, the control unit 24 is implemented by the processor using RAM or the like as a workspace to execute various programs stored in a storage device within the base station device 20. The control unit 24 can also be implemented by an integrated circuit such as an ASIC or FPGA. A CPU, MPU, ASIC, or FPGA can all be considered a controller.

[0193] <2-4. Configuration of broadcast station equipment>

[0194] Next, the configuration of the broadcasting station device 30 will be described. Figure 6 3 is a diagram illustrating a configuration example of a broadcast station device 30 according to Embodiment 1. The broadcast station device 30 is a device that carries timing information or control information about broadcast waves and transmits the broadcast waves to the terminal devices 40. The broadcast station device 30 includes a signal processing unit 31, a satellite receiving unit 35, a storage unit 32, a network communication unit 33, and a control unit 34. Figure 6The configuration shown in is a functional configuration, and the hardware configuration may be different from this. In addition, the functions of the broadcast station device 30 may be distributed and implemented in a plurality of physically separated configurations.

[0195] The signal processing unit 31 is a signal processing unit for transmitting broadcast waves. The signal processing unit 31 operates according to the control of the control unit 34.

[0196] The satellite receiving unit 35 is a signal processing unit for receiving satellite waves and demodulating information (signals). The satellite waves received by the satellite receiving unit 35 are, for example, GPS waves transmitted from GPS satellites. The satellite receiving unit 35 demodulates, for example, PPS signals and GPS time information from the GPS waves and outputs the PPS signals and GPS time information. The satellite waves received by the satellite receiving unit 35 may also be satellite waves transmitted from another GNSS system, such as GLONASS, Galileo, or Quasi-Zenith Satellites.

[0197] The storage unit 32 is a data readable / writable storage device such as a DRAM, an SRAM, a flash memory, and a hard disk. The storage unit 32 serves as storage means of the broadcast station device 30.

[0198] The network communication unit 33 is a communication interface for communicating with other devices. For example, the network communication unit 33 is a LAN interface. The network communication unit 33 can be a wired interface or a wireless interface. The network communication unit 33 serves as a network communication device for the broadcast station device 30. The network communication unit 33 communicates with the server device 10 under the control of the control unit 34.

[0199] The control unit 34 is a controller that controls each unit of the broadcast station device 30. The control unit 34 is implemented, for example, by a processor such as a CPU or MPU. For example, the control unit 34 is implemented by the processor executing various programs stored in a storage device within the broadcast station device 30 using RAM or the like as a workspace. The control unit 34 can also be implemented by an integrated circuit such as an ASIC or FPGA. A CPU, MPU, ASIC, or FPGA can all be considered a controller.

[0200] like Figure 6 As shown in , the control unit 34 includes an acquisition unit 341 and a sending unit 342. Each block (from the acquisition unit 341 to the sending unit 342) constituting the control unit 34 is a functional block indicating the function of the control unit 34. These functional blocks may be software blocks, or may be hardware blocks. For example, each of the above functional blocks may be a software module implemented by software (including a microprogram), or may be a circuit block on a semiconductor chip (die). Of course, each functional block may be a processor or an integrated circuit. The method of configuring the functional blocks is arbitrary.

[0201] The control unit 34 may be configured in a functional unit different from the above-described functional blocks. The operation of each block (from the acquisition unit 341 to the transmission unit 342) constituting the control unit 34 will be described below.

[0202] As described above, the broadcast station device 30 carries timing information about the broadcast wave and transmits the resulting broadcast wave to the terminal device 40. The timing information is virtual satellite transmission information generated by imitating information transmitted from a navigation satellite. In this case, the broadcast wave can be a wave obtained by down-converting a virtual satellite wave (e.g., a GPS wave) transmitted from a virtual satellite. In addition, the virtual satellite transmission information can be a PPS signal obtained by decoding a radio wave from a navigation satellite (e.g., a GPS satellite), or a radio wave from which an equivalent PPS signal is obtained. Navigation satellites are not limited to GPS satellites and can be GNSS navigation satellites different from GPS.

[0203] Figure 7 is a diagram illustrating a specific example of the configuration of the broadcast station device 30 . Figure 7 The configuration shown in is a configuration example of the broadcast station device 30 when there are four virtual satellites. Figure 7 The configuration shown in FIG. 1 is merely an example, and the configuration of the broadcast station device 30 is not limited to Figure 7 The configuration shown in .

[0204] The broadcast station device 30 includes a GPS and GNSS receiver 32a. The GPS and GNSS receiver 32a corresponds to Figure 6 The satellite receiving unit 35 in the example. The GPS and GNSS receiver 32a receives GPS waves from actual GPS satellites and demodulates GPS time information, etc. The GPS and GNSS receiver 32a inputs the demodulated signals to the four virtual satellite modules 31a to 31d. Figure 6 In the example of FIG, four virtual satellite modules 31a to 31d constitute a part of the signal processing unit 31. The four virtual satellite modules 31a to 31d generate signals simulating GPS satellite signals under the control of the main CPU 31a. Figure 6 In the example shown in FIG. , the main CPU 31a forms part of the control unit 34. The broadcast station device 30 adds a predetermined delay to each of the four signals according to the position of the virtual satellite, and then multiplexes the four signals to which the delays have been added. The broadcast station device 30 transmits the multiplexed signal in a predetermined frequency band (e.g., a 200 MHz band).

[0205] Although Figure 7 A configuration for transmitting timing information is illustrated, but the broadcast station device 30 may transmit control information carried on broadcast waves as well as the timing information to the terminal device 40 .

[0206] In this case, the broadcast station device 30 can use the broadband radio main channel to transmit timing information. This allows the broadcast station device 30 to broadcast accurate timing information. Alternatively, the broadcast station device 30 can use the narrowband radio subchannel to transmit control information. This allows control information to be sent to a large number of terminal devices 40. The main channel and subchannels are described below.

[0207] <2-5. Terminal Equipment Configuration>

[0208] Next, the configuration of the terminal device 40 will be described. Figure 8 This figure illustrates a configuration example of a terminal device 40 according to Embodiment 1. The terminal device 40 can perform LPWA communication with the base station device 20. The terminal device 40 extracts timing information from the broadcast waves transmitted from the broadcast station device 30 and uses this timing information to control LPWA communication. The terminal device 40 includes a wireless communication unit 41, a satellite reception unit 42, a storage unit 43, a network communication unit 44, an input / output unit 45, and a control unit 46. Figure 8 The configuration shown in is a functional configuration, and the hardware configuration may be different from such a configuration. In addition, the functions of the terminal device 40 may be distributed and implemented in a plurality of physically separated configurations.

[0209] The wireless communication unit 41 is a signal processing unit for wirelessly communicating with another wireless communication device (e.g., base station device 20 and another terminal device 40). The wireless communication unit 41 operates under the control of the control unit 46. The wireless communication unit 41 supports one or more wireless access schemes. For example, the wireless communication unit 21 supports communication using LPWA communication. The wireless communication unit 41 can multiplex and transmit multiple transmission signals generated by linear frequency modulation of transmission data within the same transmission channel by shifting the timing at predetermined time intervals.

[0210] The satellite receiving unit 42 is a signal processing unit for receiving satellite waves and demodulating information (signals). The satellite waves received by the satellite receiving unit 42 are, for example, GPS waves transmitted from GPS satellites. For example, the satellite receiving unit 42 demodulates the PPS signal, GPS time information, and other information from the GPS waves and outputs the demodulation results. The satellite waves received by the satellite receiving unit 42 may also be satellite waves transmitted from another GNSS system, such as GLONASS, Galileo, or Quasi-Zenith Satellites.

[0211] The storage unit 43 is a storage device from which data can be read and written, such as a DRAM, an SRAM, a flash memory, or a hard disk. The storage unit 43 serves as storage means of the terminal device 40.

[0212] The network communication unit 44 is a communication interface for communicating with other devices. For example, the network communication unit 44 is a LAN interface. The network communication unit 44 can be a wired interface or a wireless interface. The network communication unit 44 serves as the network communication means of the terminal device 40. The network communication unit 44 communicates with other devices under the control of the control unit 46.

[0213] The input and output unit 45 is a user interface for exchanging information with the user. For example, the input and output unit 45 is an operating device that allows the user to perform various operations, such as a keyboard, a mouse, an operating key, and a touch panel. Alternatively, the input and output unit 45 is a display device, such as a liquid crystal display or an organic electroluminescent display (organic EL display). The input and output unit 45 can be an audio device, such as a speaker or a buzzer. In addition, the input and output unit 45 can be a lighting device, such as a light emitting diode (LED) lamp. The input and output unit 45 serves as an input and output device (input device, output device, operating device, or notification device) of the terminal device 40.

[0214] The control unit 46 is a controller that controls each unit of the terminal device 40. The control unit 46 is implemented, for example, by a processor such as a CPU or an MPU. For example, the control unit 46 is implemented by the processor using RAM or the like as a workspace to execute various programs stored in a storage device within the terminal device 40. The control unit 46 can also be implemented by an integrated circuit such as an ASIC or FPGA. A CPU, MPU, ASIC, or FPGA can all be considered a controller.

[0215] like Figure 8 As shown in , the control unit 46 includes an acquisition unit 461 and a communication control unit 462. Each block (from the acquisition unit 461 to the communication control unit 462) constituting the control unit 46 is a functional block indicating the function of the control unit 46. These functional blocks may be software blocks, or may be hardware blocks. For example, each of the above-mentioned functional blocks may be a software module implemented by software (including a microprocessor), or may be a circuit block on a semiconductor chip (die). Of course, each functional block may be a processor or an integrated circuit. The method of configuring the functional blocks is arbitrary.

[0216] The control unit 46 may be configured in a functional unit different from the above-described functional blocks. The operation of each block (from the acquisition unit 461 to the communication control unit 462) constituting the control unit 46 will be described below.

[0217] As described above, the terminal device 40 extracts timing information from the broadcast waves transmitted from the broadcast station device 30 and uses this timing information to control LPWA communications. The timing information is a signal that mimics a GPS signal. If a predetermined number of GPS satellites are available, the terminal device 40 can use GPS signals (e.g., PPS signals) acquired from actual GPS satellites as timing information.

[0218] Figure 9 is a diagram illustrating a specific example of the configuration of the terminal device 40 . Figure 9 The configuration shown in is a configuration example of the broadcast station device 30 when a commercially available GPS demodulation LSI is used to demodulate the GPS signal. Figure 9 The configuration shown in FIG is merely an example, and the configuration of the terminal device 40 is not limited to Figure 9 The configuration shown in .

[0219] The terminal device 40 extracts satellite waves from the GPS satellite using a front end 42a including a surface acoustic wave (SAW) filter, a low noise amplifier (LNA), etc., and then outputs the satellite waves to the AB selector 46b. The front end 42a corresponds to Figure 8 A portion of the satellite receiving unit 42 in the example.

[0220] In addition, after the terminal device 40 extracts the broadcast wave from the broadcast station device 30 using the front end 41a including the SAW filter, LNA, etc., the terminal device 40 performs frequency shift using the up converter 41b and the down converter 42c. The terminal device 40 outputs the up-converted signal to the AB selector 46b and outputs the down-converted signal to the sub-channel demodulator 41d. The front end 41a, the up converter 41b, the down converter 42c, and the sub-channel demodulator 41d correspond to Figure 8 A portion of the wireless communication unit 41 in the example.

[0221] On the other hand, the AB selector selects a signal according to the control of the CPU 46a, and then inputs the selected signal to the GPS demodulation LSI 42b. Figure 8 In the example of FIG. 4 , the GPS demodulation LSI 42 b corresponds to a portion of the wireless communication unit 41. The GPS demodulation LSI 42 b demodulates the PPS signal and outputs the PPS signal to the LPWA transmitter 41 e. The PPS signal is a type of timing information. The LPWA transmitter 41 e corresponds to Figure 8 A part of the LPWA transmitter 41 e (for example, a control unit in the LPWA transmitter 41 e ) may be regarded as a part of the control unit 46 .

[0222] The sub-channel demodulator 41d demodulates the control signal from the input signal and outputs the control signal to the CPU 46a. Figure 8In the example shown in FIG. 4 , the CPU 46 a corresponds to a part of the control unit 46 . The LPWA transmitter 41 e communicates with the base station device 20 under the control of the control unit 46 .

[0223] <2-6. Frequency Band Allocation>

[0224] Next, we will describe the allocation of a frequency band (second frequency band). The second frequency band is a license-free band that is different from the first frequency band and can accommodate multiple communication methods. Here, the first frequency band is, for example, a band capable of performing specific small power-saving radio operations (for example, the band used by terminal device 40 for LPWA communication). For example, the first frequency band is the 920 MHz band, and the second frequency band is, for example, the VHF (high frequency) band.

[0225] Figure 10 3 is a diagram illustrating the spectrum of broadcast waves transmitted by the broadcast station device 30. The broadcast station device 30 divides the allocated frequency band (second frequency band) into a main channel and a plurality of sub-channels. The broadcast station device 30 transmits timing information using the main channel and transmits control information for controlling communication of the terminal device 40 on the sub-channels.

[0226] In this case, the broadcast station device 30 uses a broadband radio for the main channel. Assume that the bandwidth is up to approximately 2 MHz. For example, the broadcast station device 30 performs spectrum spreading on the timing signal and transmits the resulting timing signal. Using a spread spectrum method, etc., the broadcast station device 30 can broadcast accurate timing information.

[0227] In addition, the broadcast station device 30 uses narrowband radio for the subchannel. The broadcast station device 30 uses the subchannel to multicast control information. The control information may be different in various wireless schemes.

[0228] Assume that the bandwidth of the subchannel is, for example, about 10 kHz. As long as the radio modulation is suitable for the bandwidth, the broadcast station device 30 can use any radio modulation, such as BPSK, FSK, and OFDM. A person who provides communication services such as application processing to the user of the terminal device 40 (for example, an IoT operator. hereinafter referred to as a service provider) can jointly use multiple channels with respect to the allocated subchannels through carrier aggregation (CA), channel bonding, etc. In addition, a service provider can divide and use one channel.

[0229] The broadcast from each broadcast station device 30 may be defined in advance so that broadcast waves can be distinguished from each other even at the same frequency by code multiplexing.

[0230] <<3. Communication System Operation>>

[0231] Next, the operation of the communication system 1 will be described.

[0232] <3-1. Operation Overview>

[0233] First, an overview of the operation of the communication system 1 will be described. Figure 11 is a diagram illustrating an overview of the operation of the communication system 1 .

[0234] [Step S1]

[0235] The broadcast station device 30 is independent of the terminal device 40 (eg, IoT terminal) and periodically broadcasts timing information using a primary channel (step S1 ).

[0236] (1) Data broadcast from the main channel may include not only timing information but also date and time information and ephemeris information. When a terminal device 40 is synchronized with another terminal device 40, time information such as GPS time information may also be considered as timing information.

[0237] (2) The data broadcast from the main channel may also include a control signal of the terminal device 40 (eg, IoT terminal) that conforms to its usage frequency band.

[0238] [Steps S2 and S3]

[0239] Steps S2 and S3 are normal operations of the terminal device 40 (eg, IoT terminal), the base station device 20 (eg, IoT gateway), and the server device 10 .

[0240] (1) The server device 10 specifies a terminal ID for reception to the base station device 20 (eg, IoT gateway) (step S3 ).

[0241] (2) The base station device 20 (eg, IoT gateway) receives an uplink of the terminal device 40 (eg, IoT terminal) having a designated terminal ID (step S2).

[0242] (3) The base station device 20 (eg, IoT gateway) uploads the received uplink data (payload) to the server device 10 (step S3 ).

[0243] [Steps S1, S4, S5]

[0244] Steps S1 , S4 , and S5 are operations when there is a request to stop the terminal device 40 (for example, IoT terminal) having a specific ID, for example.

[0245] (1) The server device 10 notifies the control signal encoder in the broadcast station device 30 of data for stopping the terminal device 40 (for example, IoT terminal) having a specific ID (step S4 ).

[0246] (2) The control signal encoder of the broadcast station device 30 performs default encoding and transmits the resultant data to the modulator.

[0247] (3) The modulator of the broadcast station device 30 performs default modulation.

[0248] (4) The broadcast station device 30 broadcasts data via the sub-channels (step S5).

[0249] (5) The broadcast station device 30 may also broadcast data via the main channel (step S1).

[0250] <3-2. Broadcast Station Main Channel (Virtual (Pseudo) Satellite)>

[0251] In this embodiment, the broadcast station device 30 generates and broadcasts timing information. The timing information can be generated using virtual satellite (also called pseudolite) technology.

[0252] The broadcast station device 30 can generate pseudolites in a ground-based augmentation system (GBAS). Pseudolites are a well-known technology and are used in construction sites or indoor areas where the number of satellites is reduced or satellite reception is impossible due to the influence of buildings. The number and arrangement of satellites can be improved.

[0253] The broadcast station device 30 may be a terrestrial broadcast station that converts a baseband signal observed when receiving radio waves from a plurality of immobile pseudo-satellites at a point on the ground into a "high transmission frequency" and transmits the resulting signal. In this case, the "high transmission frequency" may be a frequency in the television broadcast band.

[0254] <3-3. Processing flow of broadcast station equipment>

[0255] Next, the processing flow of the broadcast station device 30 will be described. Figure 12 : is a flowchart illustrating an example of a broadcast process according to Embodiment 1. The broadcast process shown below is executed by, for example, the control unit 34 of the broadcast station device 30. The broadcast station device 30 is, for example, a terrestrial broadcast station device.

[0256] First, the acquisition unit 341 of the broadcast station device 30 acquires information (eg, GPS signal) from satellite waves (step S101). The acquisition unit 341 acquires information for time measurement or timing measurement (eg, PPS signal) transmitted from a navigation satellite.

[0257] The acquisition unit 341 acquires the timing information broadcast to the terminal device 40 (step S102). For example, the acquisition unit 341 generates the timing information based on the information (signal) acquired in step S101. As described above, the terminal device 40 can use a predetermined unlicensed frequency band (first frequency band) in which multiple communication methods can be mixed in a predetermined communication method (for example, a communication method that conforms to a predetermined LPWA standard).

[0258] Timing information is virtual satellite transmission information generated by imitating information transmitted from a navigation satellite. In this case, the virtual satellite transmission information can be formed so that a pulse per second (PPS) signal can be demodulated from a signal transmitted from a navigation satellite.

[0259] The acquisition unit 341 acquires control information from the server device 10 (step S103). The control information is, for example, information for instructing the terminal device 40 to control communication. The control information may include stop information for stopping radio wave transmission in the first frequency band in which the terminal device 40 is already using. In addition, the control information may include scheduling information for scheduling radio wave transmission in the first frequency band in which the terminal device 40 is already using. The scheduling information may include information about radio wave resources (frequency and / or time resources) that the terminal device 40 can use.

[0260] The transmission unit 342 of the broadcast station device 30 broadcasts the timing information and the control information using a frequency band (second frequency band) different from the predetermined license-exempt frequency band (first frequency band).

[0261] For example, the transmission unit 342 transmits timing information using the main channel described in <Allocation of 2-6 frequency bands>. In addition, the transmission unit 342 transmits control information using the sub-channel described in <Allocation of 2-6 frequency bands>.

[0262] In this case, the transmission unit 342 can change the spread code or code multiplexing used to transmit information using the main channel so that the broadcast wave of another broadcast station and the broadcast wave of its own station can be separated and demodulated even at the same frequency. Figure 13 is a diagram illustrating that regions can be separated by different spreading codes or code multiplexing. The transmitting unit 342 can enable region division not only for the main channel but also for the sub-channel using the same device.

[0263] When the transmission of the information is completed, the control unit 34 of the broadcast station device 30 ends the broadcasting process.

[0264] <3-4. Processing flow of terminal equipment>

[0265] Next, the processing flow of the terminal device 40 will be described. Figure 14 : is a flowchart illustrating an example of a transmission process according to Embodiment 1. The transmission process shown below is executed by the control unit 46 of the terminal device 40 , for example.

[0266] When the power is turned on, the control unit 46 of the terminal device 40 performs terminal initialization (step S201). The control unit 46 of the terminal device 40 performs a subchannel demodulation sequence, a GPS satellite acquisition sequence, and a main channel demodulation sequence. These sequences can be performed in parallel.

[0267] First, a subchannel demodulation sequence will be described.

[0268] The acquisition unit 461 of the terminal device 40 performs demodulation of the subchannel (step S211). When the demodulation fails (step S212: No), the acquisition unit 461 returns to step S211 and continues demodulation of the subchannel. When the demodulation is successful (step S212: Yes), the acquisition unit 461 returns to step S211 after executing WAIT (step S213) and repeats the demodulation of the subchannel. Figure 14 In the , "WAIT" means waiting until a predetermined time has passed, or before or after LPWA transmission.

[0269] When the demodulation is successful, the acquisition unit 461 of the terminal device 40 acquires control information from the demodulation information. The control information may include stop information for stopping the radio wave transmission in the first frequency band in which the terminal device 40 has been used. In addition, the control information may include scheduling information for scheduling the radio wave transmission in the first frequency band in which the terminal device 40 has been used.

[0270] The communication control unit 462 of the terminal device 40 generates a control signal for controlling LPWA transmission based on the control information (step S214). For example, the communication control unit 462 generates a stop signal for stopping radio wave transmission or generates a signal for specifying available radio wave resources based on the control information.

[0271] Next, the GPS satellite acquisition sequence will be described.

[0272] The acquisition unit 461 of the terminal device 40 performs a process for capturing a navigation satellite (e.g., a GPS satellite) (step S221). If a predetermined number (e.g., four) of navigation satellites can be captured (step S222: Yes), the acquisition unit 461 returns to step S221 after executing WAIT (step S223) and restarts the process for capturing the navigation satellites. Furthermore, if the capture is successful, the acquisition unit 461 transmits timing information (e.g., a timing signal such as a PPS signal or a GPS signal) to the AB selector. This timing information enables timing to be shared with another terminal device 40 that uses the first frequency band using a communication method different from the predetermined communication method used by the terminal device 40.

[0273] If the predetermined number (e.g., four) of navigation satellites cannot be acquired (step S222: No), the acquisition unit 461 determines whether a predetermined time has elapsed since the start of the acquisition process (step S224). If the predetermined time has not elapsed (step S224: Yes), the acquisition unit 461 returns to step S221 and continues the acquisition process. If the predetermined time has elapsed (step S224: No), the acquisition unit 461 proceeds to the primary channel demodulation sequence.

[0274] Next, the main channel demodulation sequence will be described.

[0275] The acquisition unit 461 of the terminal device 40 executes a process for acquiring a virtual satellite (e.g., a virtual GPS satellite) (step S231). The process for acquiring a virtual satellite is, for example, a process for demodulating the primary channel. If a predetermined number (e.g., four) of virtual satellites can be acquired (step S232: Yes), the acquisition unit 461 returns to step S221 after executing WAIT (step S233) and restarts the process for acquiring a navigation satellite. If acquisition is successful, the acquisition unit 461 transmits timing information (e.g., a timing signal such as a PPS signal or a GPS signal) to the AB selector.

[0276] If a predetermined number (e.g., four) of virtual satellites cannot be captured (step S232: No), the acquisition unit 461 determines whether a predetermined time has elapsed since the start of the capture process (step S234). If the predetermined time has not elapsed (step S234: Yes), the acquisition unit 461 returns to step S231 and continues the capture process. If the predetermined time has elapsed (step S234: No), the acquisition unit 461 proceeds to the GPS satellite capture sequence.

[0277] The AB selector selects the valid sequence side. That is, the AB selector selects either the primary channel demodulation sequence (first information) or the information acquired by the GPS satellite acquisition sequence (second information) (step S241). For example, the AB selector selects the second information when a predetermined number of navigation satellites can be acquired, and selects the first information when the predetermined number of navigation satellites cannot be acquired.

[0278] The communication control unit 462 of the terminal device 40 controls transmission of LPWA transmission data based on the control signal generated in step S214 and the information selected in step S241 (for example, timing information such as a PPS signal and a GPS signal) (step S251 ).

[0279] For example, when the communication control unit 462 can capture a predetermined number of navigation satellites, the communication control unit 462 controls communication in a predetermined communication method using the first frequency band based on the second information. On the other hand, when the communication control unit 462 cannot capture the predetermined number of navigation satellites, the communication control unit 462 controls communication in a predetermined communication method using the first frequency band based on the timing information included in the first information.

[0280] Furthermore, when the communication control unit 462 receives an instruction to stop the radio wave transmission in which the first frequency band has been used as the control information, the communication control unit 462 stops the radio wave transmission in which the first frequency band has been used.

[0281] When the transmission is completed, the control unit 46 of the terminal device 40 ends the transmission process.

[0282] <<4. Conclusion of Example 1>>

[0283] As described above, according to an embodiment of the present disclosure, a communication device (e.g., terminal device 40) acquires information (e.g., timing information and / or control information) for communication using a predetermined unlicensed band (e.g., 920 MHz band) in which multiple communication methods can be mixed, from another frequency band (e.g., 200 MHz band) different from the predetermined unlicensed band. The communication device controls communication (e.g., LPWA communication) using the predetermined communication method using the predetermined unlicensed band based on the acquired information.

[0284] This allows multiple communication devices using different communication methods to cooperate in a predetermined unlicensed frequency band, thereby achieving efficient use of wireless resources.

[0285] Furthermore, using broadcast waves of several tens of kW of power from a broadcasting station enables communication control of wireless communications in a frequency band different from that of the broadcast waves.

[0286] Furthermore, timing information is carried on the primary channel, so that even when wireless communication standards are different, a mechanism for achieving LPWA transmission aligned in the time axis direction can be provided using the timing obtained from the timing information.

[0287] In addition, in this embodiment, another frequency band (e.g., 200 MHz band) is divided into a main channel and sub-channels. A mechanism can be provided for carrying general-purpose information on the main channel and giving individual information for various wireless communications to the sub-channels.

[0288] In addition, in this embodiment, various types of information are transmitted using the main channel or the sub-channel. For example, this makes it possible to provide a mechanism that can stop wireless transmission in the event of a disaster.

[0289] Furthermore, since wideband radio is used for the primary channel, the accuracy of timing information to be broadcast is improved.

[0290] Since the ephemeris information required for GPS demodulation contained in the main channel of the broadcasting station becomes a fixed value, there is no need to update the ephemeris (to four hours from the expiration date), and the time until the GPS outputs the position coordinates can be shortened.

[0291] <<5. Example 2>>

[0292] Next, the communication system 2 of Embodiment 2 will be described.

[0293] <5-1. Technical Background and Objectives>

[0294] [Related technologies]

[0295] In the IoT era, various devices connect to the internet using wireless technology. According to the Ministry of Internal Affairs and Communications' 2017 Information and Communications White Paper, a long-range, low-power wireless technology known as Low Power Wide Area (LPWA) is expected to expand rapidly and be used by nearly 400 million wireless devices by 2021. Three-quarters of these devices will use the unlicensed Industrial, Scientific, and Medical (ISM) band.

[0296] A large number of devices are required to establish wireless communications using the limited radio frequency band of the ISM band. Therefore, it is essential for each wireless device to reduce the time it transmits radio waves to improve communication efficiency.

[0297] When downlink communications are performed to transmit accurate time information to each wireless device, the internal oscillator of each device can be calibrated. This ensures accurate wireless communication frequencies and enables efficient (i.e., short-duration) wireless communication. Unnecessary signals (preambles) that indicate the start of transmission can also be eliminated, contributing to efficient use of the frequency band during short-duration communications.

[0298] Furthermore, downlink communication makes it possible to control transmission conditions of wireless devices and improve communication efficiency.

[0299] However, in the current ISM band, downlink transmission has limitations such as antenna power, transmission channels, and transmission time, making it difficult to transmit downlink communications to all devices.

[0300] [Target]

[0301] Therefore, in this embodiment, the goal is to achieve downlink communication capable of transmitting accurate time information, control information from the system, and the like to each device.

[0302] <5-2. Transmission of Time Information (Related Technologies and Objectives)>

[0303] [Related technologies]

[0304] The method for wirelessly transmitting time information includes standard radio waves (JJY), with 50kW radio waves transmitted from Fukushima and Saga prefectures. Furthermore, the radio wave frequencies used in Fukushima and Saga prefectures are 40kHz and 60kHz, respectively, preventing interference between the two types of radio waves. However, due to the low frequency of JJY radio waves, only approximately one second of time accuracy can be achieved. Furthermore, due to the narrow frequency band, radio waves cannot be received indoors, and device control information cannot be transmitted.

[0305] Due to the lack of accuracy of JJY, GPS (called GNSS when including systems outside the United States) is often used as a means of obtaining accurate time information. GPS is composed of dozens of artificial satellites orbiting the earth, and radio waves are captured from the artificial satellites, so that the position (latitude and longitude) and time of the receiving point can be accurately known. The time accuracy is a high precision of less than one microsecond. However, since the artificial satellites are as long as 20,000 kilometers away, the radio waves are weak and cannot be received indoors. In addition, since the satellites are in orbit and are not stationary, the GPS receiver should need to obtain the orbital information of the satellites for a long time (tens of seconds to one minute). There is also a problem that power consumption increases due to receiving this orbital information.

[0306] Therefore, in the present embodiment, downlink broadcasting in which accurate time information is transmitted with strong radio waves from a broadcasting base is realized.

[0307] [question]

[0308] For such downlink broadcasting, the following four technical problems need to be solved.

[0309] (Question 1) Regional overlap problem

[0310] (Question 2) Achieving high time accuracy

[0311] (Question 3) Practical use of inexpensive receiving equipment

[0312] (Question 4) Operate in a short time to achieve low power consumption

[0313] (Problem 1: Regional overlap)

[0314] Figure 15 This figure illustrates Problem 1 of Example 2. In areas where radio waves from two or more broadcasting stations can be received (overlapping areas), the radio waves interfere and cannot be properly received. Because the radio waves from the broadcasting stations are strong, they may unexpectedly reach great distances. Therefore, it is necessary to change (A) the frequency, (B) the time, or (C) the spreading code depending on the broadcasting station.

[0315] (A) Frequency varies depending on the region

[0316] When using narrowband, the number of channels can be increased, and each broadcast station is assigned a frequency channel for transmission, thus preventing overlap. However, the receiver must scan many narrowband frequencies, which complicates the configuration. In addition, the narrower the frequency band (narrowband), the lower the time resolution, and (Issue 2: High Time Accuracy) cannot be solved.

[0317] (B) Delivery time varies depending on the area

[0318] The problem of overlapping regions can be solved by allocating a frame of transmission time for each region. However, since the receiver does not know the transmission timing, it must perform reception continuously. Therefore, (Problem 4: Operation within a short time) cannot be solved.

[0319] (C) Diffusion code changes depending on the region (present embodiment)

[0320] The overlap problem can be solved by using spectrum spreading and changing the spreading code for each area. For example, using spectrum spreading with 1 Mbps BPSK as the modulation scheme and changing the spreading code for each area can solve the overlap problem. In this case, the frequency band is extended to 2 MHz.

[0321] (Problem 2: Achieving high time accuracy)

[0322] Figure 16 This diagram illustrates Problem 2 of Example 2. The time accuracy is determined by the inverse of the frequency band. In this example, a spread spectrum method using 1 Mbps BPSK modulation is used to achieve a time accuracy of 1 microsecond.

[0323] (Issue 3: Allowing cheap receiving equipment)

[0324] Figure 17 This figure illustrates Problem 3 of Example 2. In this embodiment, a spread spectrum method is employed, and a communication format compliant with GPS is used. Therefore, the receiver circuit in this solution can directly utilize a widely available GPS receiver circuit, significantly reducing the price.

[0325] (Question 4: Can it be received in a short time)

[0326] Figure 18 This figure illustrates Problem 4 of Example 2. In this embodiment, a GPS baseband signal observed when receiving radio waves from a pseudolite at a point on the ground is created, converted to a high-frequency band, and transmitted. Because pseudolites do not move, there is no need to acquire satellite orbit information, and the receiver can complete the reception operation in a short time. This reduces the receiver's power consumption.

[0327] <5-3. System Configuration>

[0328] The problems of the present embodiment have been described above, and the configuration of the communication system 2 of the embodiment 2 will be described below. Figure 19 is a diagram illustrating a configuration example of a communication system 2 according to Embodiment 2. Figure 19 The configuration of the communication system 2 is described. The description of "communication system" may be replaced with other words such as "control system".

[0329] [System Overview]

[0330] The communication system 2 is a data transmission and reception system including a control information transmitter 300 that transmits control information to an LPWA transmitting terminal 400, the LPWA transmitting terminal 400 that transmits data based on the control information, and a receiving system (e.g., an LPWA receiver 200) that receives data in synchronization with GPS time. The communication system 2 is an LPWA transmitting terminal control system, wherein the control information includes GPS time information.

[0331] Furthermore, the communication system 2 is a data transmission control system in which control information is transmitted by spread spectrum, and the frame timing of the spread spectrum signal is synchronized with the GPS time.

[0332] Furthermore, the communication system 2 is an LPWA transmitting terminal control system, in which the control information includes TMCC information indicating a disaster occurrence situation or a communication channel status.

[0333] Furthermore, the communication system 2 is an LPWA transmitting terminal control system in which the transmission carrier frequency of the control information transmitter 300 is 170 MHz or higher and 220 MHz or lower.

[0334] [Specific example of system configuration]

[0335] The overview of the communication system 2 has been described, but a specific example of the configuration of the communication system 1 will be described below.

[0336] The communication system 2 includes a control information transmitter 300, an LPWA transmitting terminal 400 and an LPWA receiver 200. Figure 19 The central information control device can also be regarded as part of the communication system 2.

[0337] (Central Information Control Equipment)

[0338] The central information control device notifies the control information transmitter 300 of disaster information and communication channel information when an earthquake or disaster occurs as TMCC information. In the first embodiment, the control information transmitter 300 corresponds to the server device 10, for example. Of course, the control information transmitter 300 is not limited to the server device 10.

[0339] (Control Information Transmitter)

[0340] The control information transmitter 300 receives radio waves from GPS satellites orbiting the Earth to obtain GPS time information. The control information transmitter 300 collects GPS time information and TMCC information (disaster information, communication channel information, etc. obtained from the central control device) to create control information. The control information transmitter 300 spreads the control information as a spectrum spread signal with a chip rate of 1.023 MHz and transmits the control information in the frequency band (170 MHz to 220 MHz) that already uses broadcast waves. In the first embodiment, the control information transmitter 300 corresponds to the broadcast station device 30, for example. Of course, the control information transmitter 300 is not limited to the broadcast station device 30.

[0341] (LPWA sending terminal)

[0342] LPWA transmitting terminal 400 is a device that transmits information from various sensors using long-range, low-bit-rate communications. Long-range, low-bit-rate wireless technologies are generally referred to as low-power wide-area (LPWA). LPWA transmitting terminal 400 is designed to transmit information from various sensors as payload using LPWA communications. In Embodiment 1, LPWA transmitting terminal 400 corresponds to terminal device 40, for example. Of course, LPWA transmitting terminal 400 is not limited to terminal device 40.

[0343] Before LPWA communication starts, the LPWA transmitting terminal 400 receives the spread spectrum radio wave transmitted from the control information transmitter 300 and decodes the control information. When the disaster information included in the control signal indicates "disaster", the LPWA transmitting terminal 400 stops transmitting to prioritize high-priority wireless communication.

[0344] The clock signal within the LPWA transmitting terminal 400 is calibrated using the GPS time included in the control information. As a result, the LPWA signal transmitted by the LPWA transmitting terminal 400 accurately matches the carrier frequency expected by the LPWA receiver 200, thereby increasing the probability of successful reception by the LPWA receiver 200 and improving communication efficiency. Furthermore, the LPWA transmission signal from the LPWA transmitting terminal 400 begins transmission at the exact time expected by the LPWA receiver 200, eliminating useless signals such as preambles and improving communication efficiency. After performing this calibration, the LPWA transmitting terminal 400 transmits information from various sensors as LPWA signals.

[0345] (LPWA receiver)

[0346] The LPWA receiver 200 receives radio waves from GPS satellites orbiting the earth and calibrates a clock signal inside the LPWA receiver 200. Therefore, the reception frequency and reception timing of the LPWA receiver 200 are accurately synchronized with the GPS time.

[0347] That is, since the LPWA transmitting terminal 400 is synchronized with the GPS time via the control information transmitter 300, and the LPWA receiver 200 is synchronized with the GPS time by directly receiving radio waves from GPS satellites, both transmission and reception are performed in synchronization with the GPS time, thereby improving the stability and efficiency of communication.

[0348] The LPWA signal received by the LPWA receiver 200 is displayed on the smartphone in the user's hand via a server on a network (eg, the Internet).

[0349] The LPWA receiver 200 corresponds to, for example, the base station device 20 in Embodiment 1. Of course, the LPWA receiver 200 is not limited to the base station device 20 .

[0350] The illustrated smartphone is merely an example and may be replaced with another terminal device such as a mobile phone, a smart device (smartphone, tablet, etc.), a PDA, a personal computer, an M2M device, or an IoT device.

[0351] In addition, the network is not limited to the Internet. The network may include, for example, a communication network (including the Internet), such as a regional Internet Protocol (IP) network or a telephone network (e.g., a fixed telephone network or a mobile phone network). In this case, the network may include a wired network or may include a wireless network.

[0352] Hereinafter, the configuration of each device constituting the communication system 2 will be described in detail. The configuration of each device shown below is only an example. The configuration of each device may be different from the configuration below.

[0353] <5-4. Configuration of Control Information Transmitter>

[0354] First, the configuration of the control information transmitter 300 will be described. Figure 20 is a diagram illustrating a configuration example of a control information transmitter 300 according to Embodiment 2.

[0355] [Device Overview]

[0356] The control information transmitter 300 is a transmitting device, which includes a time information acquisition device (time acquisition device), a transmission data creation device for creating control information including time information, a spectrum expansion device for modulating the control information by spectrum expansion to create a modulated signal, a timing correction device for adjusting the timing of the modulated signal according to the time information, and a transmitting device.

[0357] The control information transmitter 300 is a transmitting device in which the time information acquisition means is a GPS receiver that receives radio waves from a GPS satellite (typically a GNSS satellite).

[0358] The control information transmitter 300 is a transmitting device in which a timing correction means performs correction so that a modulated signal is synchronized with GPS time.

[0359] The control information transmitter 300 is a transmitting device, wherein the control information includes TMCC information, such as disaster information or communication channel information.

[0360] The control information transmitter 300 is a transmitting device in which the transmission data creating means generates time information as a 300-bit subframe and the bit rate is 50 bps.

[0361] The control information transmitter 300 is a transmitting device in which the spectrum spreading means has a chip rate of 1023 kHz and a spreading code length of 1023 chips.

[0362] The control information transmitter 300 is a transmitting device, wherein the transmitting means includes frequency correction means for correcting the transmission carrier frequency based on time information.

[0363] The control information transmitter 300 is a transmitting device in which a transmission carrier frequency of the transmitting means is 170 MHz or more and 220 MHz or less.

[0364] [Specific example of device configuration]

[0365] The overview of the control information transmitter 300 has been described above, and the configuration of the control information transmitter 300 will be described in detail hereinafter.

[0366] like Figure 20 As shown in , the control information transmitter 300 includes a time acquisition device, a transmission data creation device, a spectrum expansion device, a timing correction device and a transmission device. Figure 20 In the description, MIX, PRN, BPF, and PA have the following meanings.

[0367] MIX: Mixer

[0368] PRN: Pseudo-random number

[0369] BPF: Bandpass filter

[0370] PA: Power amplifier

[0371] Figure 20 The configuration shown in is a functional configuration, and the hardware configuration may be different from such a configuration. In addition, the functions of the control information transmitter 300 may be distributed and implemented in a plurality of physically separated configurations.

[0372] (Time acquisition device)

[0373] The time acquisition device uses a GPS antenna and a GPS receiver to receive GPS satellites orbiting the earth and output the GPS time. The GPS time can be obtained with a high accuracy of 1 microsecond.

[0374] (Sending data creation device)

[0375] The transmission data creation device includes a CPU. The CPU adds 6 seconds to the acquired GPS time to create the time of week (TOW: 17 digits) and week number (WN: 10 digits) of the transmission start time. Using TOW and WN, the GPS time to start transmission is specified in 6-second units.

[0376] The CPU adds the TMCC information (174 bits), the authentication data Auth (32 bits) and the CRC (24 bits) to form a subframe (300 bits), as shown in FIG. Figure 21 Here, the Transmission and Multiplexing Configuration Control Information (TMCC) is information indicating the occurrence of a disaster or the status of a communication channel. TMCC can be used as information to control LPWA transmitting terminals. Authentication data Auth is a code used to detect whether communication information has been tampered with, and CRC is a code used to detect errors that have occurred in the communication path.

[0377] The TLM is 30 bits of information, consisting of, for example, a header (10001011) and a 6-bit parity check. The HOW is information that stores the time of week (TOW) at the beginning and uses the subsequent end as parity, indicating the time every 6 seconds. The 10-bit week number (WN) is time information for the year, month, and day of the week.

[0378] The 300-bit subframe configured as described above becomes transmission data of 1-bit unit due to the P / S converter and is supplied to the spectrum spreading apparatus.

[0379] (Spectrum Spreading Device)

[0380] The spectrum spreader repeatedly multiplies one bit of transmitted data by a pseudorandom number sequence (PRN) 20 times to increase the number of bits. Here, the PRN is a 1023-bit pseudorandom number sequence, so one bit of transmitted data is spread into 20,460 symbols. The symbol rate is 1.023M symbols / second.

[0381] (Timing Correction Device)

[0382] The timing correction device is composed of a FIFO memory (not shown), a delay line, and the like, and performs timing adjustment by applying a predetermined delay so that the transmitted symbol is synchronized with GPS time. Specifically, the delay is adjusted so that the timing of the radio wave transmitted from the control information transmitter 300 matches the timing at which the radio wave transmitted from the virtual GPS satellite is received on the ground. Here, the virtual satellite is a non-existent satellite, and the flight altitude of the virtual satellite is specified, so that the delay time at which the radio wave transmitted from the virtual satellite is received on the ground can be calculated.

[0383] When the time added to the GPS time in the transmission data creation device is 6 seconds, the radio wave transmission speed is C, and the flight altitude of the virtual satellite (the distance from the control information transmitter 300) is H, the delay amount D is calculated using the following equation (1).

[0384] D = 6 seconds - (H / C) + α... (1)

[0385] Here, α is a delay time caused by electronic components of the control information transmitter 300 .

[0386] Therefore, the timing correction device adjusts the delay amount according to the set flight altitude of the virtual satellite. By controlling the delay time in this way, the radio waves transmitted from the control information transmitter 300 become radio waves as if the GPS satellite is flying at altitude H. Such radio waves are received by the GPS receiver, making it possible to obtain correct time information.

[0387] (Sending device)

[0388] The transmitting device uses a phase-locked loop (PLL) to convert the reference clock provided by the crystal oscillator (OSC) to a high frequency, and uses a mixer (MIX) to multiply the clock by the transmission symbol to perform conversion to a high carrier frequency. Here, the carrier frequency is set to the VHF-high frequency band (170MHz to 220MHz) of old analog TV, so that it can use the available channels of TV broadcasting to transmit at high output. Figure 22 is a diagram illustrating the spectrum of the transmission wave. The spectrum is expanded when multiplied by PRN, and has a frequency band of about 2 MHz centered on the carrier frequency Fc, as shown Figure 22 As shown in .

[0389] The oscillation frequency of the crystal oscillator (OSC) is counted based on the timing pulse from the GPS receiver, so that the frequency deviation of the OSC can be obtained. This frequency deviation is fed back to the PLL circuit, so that the frequency deviation of the OSC is eliminated to transmit at the correct frequency.

[0390] <5-5. LPWA Transmitter Configuration>

[0391] Next, the configuration of the LPWA transmitting terminal 400 will be described. Figure 23 is a diagram illustrating a configuration example of an LPWA transmitting terminal 400 according to Embodiment 2. More specifically, Figure 23 The diagram illustrates a configuration example of a long-distance low-bit-rate radio (LPWA) transmitting terminal 400 that transmits temperature information obtained from a temperature sensor as LPWA.

[0392] The radio waves transmitted from the control information transmitter 300 are converted into electrical signals by the receiving antenna, and only the signal components centered around the carrier frequency Fc are extracted by the SAW filter. In this example, the carrier frequency Fc is set to 200 MHz. The signal that passes through the SAW filter is amplified to a constant amplitude by the AGC amplifier, multiplied by the 1375 MHz local oscillator LO by the mixer (MIX), and then frequency-converted to 1575 MHz. The signal transmitted from the control information transmitter 300 has the same signal format (spectrum spread) as the signal used in GPS and is synchronized with GPS time. Therefore, the radio waves received by the receiving antenna are frequency-converted to 1575 MHz, so that the signal detection can be performed using the same semiconductors as those used in commercially available GPS receivers. That is, since the spectrum spread signal can be despread and decoded in the same way as the radio waves from the GPS satellite, it can be output Figure 21 The subframe (300 bits) of transmitted data is shown in .

[0393] Therefore, GPS time with 6-second accuracy can be obtained from the TOW and WN information located near the beginning of the subframe. Furthermore, GPS time information with 1-microsecond accuracy is output based on the timing of the subframe detection. This GPS time information is provided to the LPWA transmitter, enabling it to transmit at a frequency (920 MHz) and timing synchronized with GPS time. Furthermore, disaster information transmitted as TMCC information can be decoded from the subframe. When disaster information is transmitted as TMCC information, the CPU halts LPWA communications. In this way, LPWA communications are controlled using control information, freeing up valuable radio wave resources for more important communications.

[0394] Here, in order to operate the GPS receiver, the orbit information of the satellite is required. Figure 20 The satellite positions shown in FIG are fixed, so the orbital information is a fixed value. Therefore, the CPU transmits the orbital information having a fixed value stored in the CPU firmware to the GPS receiver, so that the control information transmitted from the control information transmitter 300 can be received. In this patent, since the acquisition of orbital information can be omitted in this way, the control information can be received in a short time.

[0395] As described above, the LPWA transmitting terminal 400 of the present patent can receive the control information transmitted from the control information transmitter 300 and control the LPWA transmitting terminal 400 by simply adding a simple circuit to a commercially available GPS receiver.

[0396] <5-6. LPWA Receiver Configuration>

[0397] Next, the configuration of the LPWA receiver 200 will be described. Figure 24 is a diagram illustrating a configuration example of an LPWA receiver 200 according to Embodiment 2.

[0398] The LPWA receiver 200 receives radio waves from GPS satellites orbiting the earth and calibrates a clock signal inside the LPWA receiver 200. Therefore, the reception frequency and reception timing of the LPWA receiver 200 are accurately synchronized with the GPS time.

[0399] The oscillation frequency of the crystal oscillator (OSC) is counted based on the timing pulses from the GPS receiver, allowing the OSC frequency deviation to be determined. This frequency deviation is fed back to the PLL circuit, eliminating the OSC frequency deviation, performing local oscillation at the correct frequency (920 MHz), and supplying the signal to the mixer. The 920 MHz LPWA radio signal received by the receive antenna is amplified to a predetermined amplitude by the AGC amplifier after the SAW filter removes unnecessary radio waves. The mixer multiplies the output of the AGC amplifier with the 920 MHz local oscillation signal to produce a baseband signal. The baseband signal is converted to a digital signal through A / D conversion, and the CPU performs decoding processing such as error correction to decode the sensor information. This sensor information is displayed on the user's smartphone via a server on the Internet.

[0400] As described above, the LPWA receiver 200 synchronizes with GPS time by directly receiving radio waves from GPS satellites. Since the LPWA transmitting terminal 400 synchronizes with GPS time via the control information transmitter 300 as described above, both transmission and reception are performed in synchronization with GPS time, improving communication stability and efficiency.

[0401] <<6. Example 3>>

[0402] Next, a communication system 3 of Embodiment 3 will be described.

[0403] <6-1. Problems and Solutions>

[0404] A commercially available GPS receiver is configured to receive information from at least four different satellites to obtain four unknown pieces of information (latitude, longitude, altitude, and time), and then output accurate time.

[0405] In the embodiment described so far, the control information transmitter 300 is configured to transmit radio waves of one virtual satellite. Therefore, it is necessary to change the firmware of the GPS receiver or the like so that time information is received only from the signal of one virtual satellite.

[0406] Therefore, in the present embodiment below, the radio waves of four virtual satellites are combined and transmitted from one broadcasting station. This makes it possible to reduce costs by reducing the modification of the receiver.

[0407] <6-2. System Configuration>

[0408] The problems and solutions of the present embodiment have been described above, and the configuration of the communication system 3 of the embodiment 3 will be described below. Figure 25 3 is a diagram illustrating a configuration example of a communication system 3 according to Embodiment 3. Figure 25 The configuration of the communication system 2 is described. The description of "communication system" may be replaced with other words such as "control system".

[0409] The communication system 3 includes a control information transmitter 300A, an LPWA transmitting terminal 400 and an LPWA receiver 200. Figure 25 The central information control device can also be regarded as part of the communication system 2. The communication system 3 is connected to Figure 19 The communication system 2 shown in FIG. 1 is different in that the control information transmitter 300 is a control information transmitter 300A. The configuration of devices other than the control information transmitter 300A is the same as that of the communication system 2.

[0410] <6-3. Configuration of Control Information Transmitter>

[0411] Hereinafter, the configuration of the control information transmitter 300A will be described. Figure 26 3 is a diagram illustrating a configuration example of a control information transmitter 300A according to Embodiment 3.

[0412] In Embodiment 3, a broadcast station creates and transmits radio waves equivalent to GPS radio waves from four virtual satellites received at one point on the ground. This allows GPS time information to be acquired as is using a commercially available GPS receiver.

[0413] therefore, Figure 26 The control information transmitter 300A shown in FIG3 is configured to combine and transmit signals from four virtual satellites A, B, C, and D. Here, for the four virtual satellite signals, different satellite positions and different spreading codes PRN are used.

[0414] The signal from the virtual satellite is created by each of the four virtual satellite signal creating devices 3101 to 3104 . Figure 27 3 is a diagram illustrating a configuration example of the virtual satellite signal creating device 310 . Figure 27 The virtual satellite signal creation device 310 shown in FIG is a block that puts together a transmission data creation device, a spectrum spreading device, and a timing correction device. Figure 20 The configuration is performed in the same manner as described, so its description will be omitted.

[0415] <<7. Example 4>>

[0416] Next, the communication system 4 of the embodiment 4 will be described.

[0417] <7-1. Overview of Example 4>

[0418] In this embodiment, control information is sent for each purpose to individually support various applications.

[0419] In this embodiment, a thermometer that transmits a measured value to the Internet will be described.

[0420] For example, using this thermometer, the temperature measurement interval can be changed according to the farmer's requirements.

[0421] <7-2. System Configuration>

[0422] The overview of the present embodiment has been described above, and the configuration of the communication system 4 of Embodiment 4 will be described hereinafter. Figure 28 is a diagram illustrating a configuration example of a communication system 4 according to Embodiment 4. Figure 28 The configuration of the communication system 4 is described. The description of "communication system" may be replaced with other words such as "control system".

[0423] In recent years, the internet has also been introduced to agriculture. For example, thermometers are installed in farmhouses and used to monitor the temperature using LPWA communication. In this case, frequent transmission of temperature measurements is necessary, such as during the seedling raising period. Therefore, this embodiment provides a system that can adjust the LPWA transmission interval based on requests from farmers and others.

[0424] like Figure 28 As shown in FIG, the communication system 4 includes a control information transmitter 300B, an LPWA transmitting terminal 400B and an LPWA receiver 200. The central information control device can also be regarded as a part of the communication system 2. The communication system 4 is connected to the LPWA transmitting terminal 400B. Figure 28 The communication system 2 shown in FIG is different in that the control information transmitter 300 is a control information transmitter 300A, and the LPWA transmitting terminal 400 and the LPWA transmitting terminal 400B. Figure 28In the example of , a thermometer is included as LPWA transmitting terminal 400B. Furthermore, the central control device is configured to receive various instructions from farmers. Its configuration is the same as that of communication system 2.

[0425] <7-3. Spectrum of Transmitted Waves>

[0426] exist Figure 28 In the embodiment, the measurement value transmission interval instruction from the farmer is sent as a separate control information to the control information transmitter 300B via the central control device. The control information transmitter 300B uses the wideband spectrum spread scheme as described in the previous embodiment to transmit the control information (GPS time information and TMCC information). Figure 29 is a diagram showing the spectrum of the transmitted wave. Figure 29 In the example shown, the spectrum of the transmitted wave is displayed as the main channel.

[0427] Here, in the TMCC information, the communication method of the subchannel is transmitted as communication channel information (information such as transmission frequency and modulation method.) Therefore, in this embodiment, separate control information is added to the subchannel and broadcasted.

[0428] <7-4. Configuration of Control Information Transmitter>

[0429] Next, the configuration of the control information transmitter 300B will be described. Figure 30 3 is a diagram illustrating a configuration example of a control information transmitter 300B according to Embodiment 4.

[0430] The configuration of the control information transmitter 300B is Figure 20 The configuration of the control information transmitter 300 shown in is different in that the configuration of the portion surrounded by the dotted line is added. The configuration of the portion surrounded by the dotted line enables the control information transmitter 300B to transmit separate control information.

[0431] As described above, the measurement value transmission interval instruction from the farmer is transmitted as separate control information via the central control device to the control information transmitter 300B. The control information transmitter 300B transmits the control information transmitted from the central control device to the LPWA transmitting terminal 400B.

[0432] <7-5. LPWA Transmitter Configuration>

[0433] Next, the configuration of the LPWA transmitting terminal 400B will be described. Figure 31 1 is a diagram illustrating a configuration example of an LPWA transmitting terminal 400B according to Embodiment 4. The LPWA transmitting terminal 400B is, for example, a thermometer installed in a house (e.g., a polyethylene house). The LPWA transmitting terminal 400B receives individual control information broadcasted from the control information transmitter 300B.

[0434] Configuration of LPWA transmitting terminal 400B Figure 23 The configuration of the LPWA transmitting terminal 400 shown in FIG. 1 is different in that a configuration of a portion surrounded by a dotted line is added. The LPWA transmitting terminal 400B can acquire separate control information using the configuration of the portion surrounded by the dotted line.

[0435] LPWA transmitting terminal 400B installed in the house receives the subchannel to obtain individual control information and adjusts the LPWA transmission interval. Therefore, during the seedling growth period, temperature information can be frequently transmitted to the user's terminal device (e.g., smartphone). Furthermore, when the seedling growth period ends, the LPWA transmission interval is extended to reduce interference.

[0436] <<8. Modification Example>>

[0437] Each of the above-described embodiments illustrates an example, and various changes and applications are possible.

[0438] <8-1. Modification example of embodiment>

[0439] For example, although the broadcast wave used for converting the main channel frequency into the broadcast band to obtain timing (time) information is a transmission wave from a terrestrial broadcasting station in the above-described embodiment, the following wave may be used.

[0440] (1) GPS transmits waves.

[0441] (2) Radio waves reporting a standard frequency (radio clock).

[0442] (3) Satellite-based augmentation system (SBAS) radio waves.

[0443] (4) Ground-based augmentation system (GBAS) radio waves (operating in the VHF-low frequency band).

[0444] In addition to timing information, information transmitted using the main channel can also include control information for instructing all terminal devices 40 (e.g., IoT terminals) using the broadcast wave to stop transmitting. Control from the main channel alone poses security concerns, so ultimate terminal control (e.g., IoT terminals) can be performed in conjunction with control information from sub-channels.

[0445] Furthermore, information transmitted using the primary channel may include, in addition to timing information, data that can be used to shorten the time to first fix (GPS initial position calculation time; TTFF) based on ephemeris information, almanac information, etc. used in GPS.

[0446] Additionally, one of the sub-channels may be used for a standard frequency reporting service (radio clock).

[0447] <8-2. Application Examples of the Embodiment>

[0448] Different spreading codes may be used in a plurality of broadcast station devices 30 .

[0449] In this case, when the terminal device 40 (eg, IoT terminal) can receive the broadcast waves (eg, timing signals included in the broadcast waves) of the three broadcast station devices 30 , the position of the reception point can be known.

[0450] Figure 32 and Figure 33 3 is a diagram illustrating position measurement of the terminal device 40 using radio waves of the broadcasting station device 30. Assume that each broadcasting station device 30 can be received. A to 30 C The broadcast wave areas are areas A to C, such as Figure 32 As shown in. Broadcasting station equipment 30 A to 30 C The positions of are (XA, YA), (XB, YB), and (XC, YC) respectively. It is assumed that the terminal device 40 is located in an area including all areas A to C.

[0451] Here, it is assumed that the terminal device 40 can separate the broadcast waves from the broadcast station devices 30A to 30C and can detect that the delay times from the broadcast time are TA, TB, and TC, as shown in FIG. Figure 33 As shown in .

[0452] In this case, the position (X, Y) of the terminal device 40 can be semi-determined by solving the simultaneous equations shown below.

[0453] √[(XA-X) 2 +(YA-Y) 2 ]-√[(XB-X) 2 +(YB-Y) 2 ]=c(TA-TB)

[0454] √[(XB-X) 2 +(YB-Y) 2 ]-√[(XC-X) 2 +(YC-Y) 2 ]=c(TB-TC)

[0455] √[(XC-X) 2 +(YC-Y) 2 ]-√[(XA-X) 2 +(YA-Y) 2 ]=c(TC-TA)

[0456] Here, c is the speed of radio wave propagation.

[0457] For example, this position measurement method can be used for indoor position measurement.

[0458] <8-3. Other Communication Systems>

[0459] In communication systems 1 to 4, the information to be transmitted and received is arbitrary. For example, the terminal device 40 (LPWA transmitting terminals 400 and 400B) can generate and transmit transmission information including images, sounds, measurement data, device identification information, parameter setting information, control information such as commands, etc. Furthermore, the transmission information can include various types of information, such as images and sounds, identification information and setting information, and control information.

[0460] Furthermore, the terminal device 40 (LPWA transmitting terminals 400 and 400B) may be capable of generating transmission information including information provided from another device, for example. For example, the terminal device 40 (LPWA transmitting terminals 400 and 400B) may generate and transmit transmission information including information (sensor output) output from various sensors that detect, measure, or the like, any variable such as image, light, brightness, saturation, electricity, sound, vibration, acceleration, velocity, angular velocity, force, temperature (not temperature distribution), humidity, distance, area, volume, shape, flow rate, time, time period, magnetism, chemical substances, or odor, or the amount of change thereof.

[0461] That is, the present technology can be applied to systems for any purpose such as three-dimensional shape measurement, spatial measurement, object observation, movement deformation observation, biological observation, authentication processing, monitoring, autofocus, imaging control, lighting control, tracking processing, input and output control, electronic device control, and actuator control.

[0462] In addition, the present technology can be applied to systems in any field, such as transportation, medical treatment, crime prevention, agriculture, animal husbandry, mining, beauty, factories, household appliances, weather and natural monitoring. For example, the present technology can also be applied to a system for capturing images for viewing and using a digital camera, a portable device with a camera function, etc. In addition, for example, the present technology can also be applied to a system provided for transportation, such as an on-board system that can shoot the front area, rear area, surroundings, interior, etc. of a vehicle to ensure safe driving (such as automatic stopping, identifying the driver's condition, etc.), a monitoring camera system that monitors a moving vehicle or road, or a distance measurement system that measures the distance between vehicles. In addition, for example, the present technology can also be applied to a system provided for security, in which a monitoring camera for crime prevention purposes, a camera for personal authentication purposes, etc. are used.

[0463] Furthermore, for example, the present technology can be applied to systems provided for sports, in which various sensors that can be used for sports purposes, such as wearable cameras, are used. Furthermore, for example, the present technology can be applied to systems provided for agriculture, in which various sensors, such as cameras for monitoring the status of fields and crops, are used. Furthermore, for example, the present technology can be applied to systems provided for animal husbandry, in which various sensors for monitoring the status of livestock such as pigs or cattle are used. Furthermore, the present technology can also be applied to systems for monitoring natural conditions such as volcanoes, forests, and oceans, weather observation systems for observing weather, temperature, humidity, wind speed, sunshine hours, etc., or systems for observing the ecology of wild animals such as birds, fish, reptiles, amphibians, mammals, insects, and plants.

[0464] In addition, this technology can also be applied to location notification systems, anti-theft systems, etc.

[0465] Furthermore, the specifications of the radio signals or information to be transmitted and received are arbitrary. Furthermore, although the present technology is applied to the examples of the server device 10, base station device 20, broadcast station device 30, terminal device 40, or communication systems 1 to 4 having devices equivalent to or modified from these devices as described above, the present technology can be applied to any transmitting device, any receiving device, any transmitting and receiving device, any communication device, any information processing device, and any system.

[0466] <8-4. Other modification examples>

[0467] The control device that controls the server device 10, base station device 20, broadcast station device 30, terminal device 40, LPWA receiver 200, control information transmitters 300, 300A, 300B, and LPWA transmitting terminals 400 and 400B of this embodiment can be implemented by a dedicated computer system or a general-purpose computer system.

[0468] For example, a communication program for performing the above-described operations (e.g., transmission and reception processing) is stored and distributed in a computer-readable recording medium such as an optical disc, semiconductor memory, magnetic tape, or floppy disk. For example, the control device is configured by installing the program in a computer and executing the above-described processing. In this case, the control device may be a device external to the server device 10, base station device 20, broadcast station device 30, terminal device 40, LPWA receiver 200, control information transmitters 300, 300A, and 300B, and LPWA transmitting terminals 400 and 400B (e.g., a personal computer). In addition, the control device may be a device internal to the server device 10, base station device 20, broadcast station device 30, terminal device 40, LPWA receiver 200, control information transmitters 300, 300A, and 300B, and LPWA transmitting terminals 400 and 400B (e.g., control unit 13, control unit 24, control unit 34, or control unit 46).

[0469] In addition, the above-mentioned communication program may be stored in a disk device included in a server device on a network (such as the Internet), so that the communication program can be downloaded to a computer, etc. In addition, the above-mentioned functions may be realized by cooperation between an operating system (OS) and application software. In this case, the parts other than the OS may be stored in a medium and distributed, or the parts other than the OS may be stored in a server device so that the parts can be downloaded to a computer, etc.

[0470] Furthermore, all or part of the processing described in the above embodiments as being automatically performed may be performed manually, or all or part of the processing described as being manually performed may be performed automatically using known methods. Furthermore, unless otherwise specified, the processing procedures, specific names, and information including various types of data or parameters illustrated in the above documents or drawings may be arbitrarily changed. For example, the various types of information shown in the drawings are not limited to the information shown.

[0471] In addition, each component of each device shown in the figure is a functional concept and does not necessarily have to be physically configured as shown in the figure. That is, the specific form of distribution and integration of each device is not limited to the form shown in the figure, and all or part of it can be functionally or physically distributed and integrated in any unit according to various loads or usage situations.

[0472] Furthermore, the above-described embodiments can be appropriately combined in a field where the processing contents do not contradict each other. Furthermore, the order of the respective steps shown in the flowcharts of the above-described embodiments can be appropriately changed.

[0473] In addition, for example, the present embodiment can also be implemented as any configuration constituting a device or system, such as a processor as a system large-scale integration (LSI), a module using multiple processors, a unit using multiple modules, a collection of other functions added to a unit, etc. (i.e., a configuration of a part of a device).

[0474] In this embodiment, a system refers to a collection of multiple components (devices, modules (parts), etc.), and it does not matter whether all components are in the same housing. Therefore, multiple devices housed in separate housings and connected via a network, and a single device in which multiple modules are housed in a single housing, are both systems.

[0475] Furthermore, for example, the embodiment may have a cloud computing configuration in which one function is shared and jointly processed by a plurality of devices via a network.

[0476] 9. Conclusion

[0477] As described above, according to the embodiments of the present disclosure, efficient use of wireless resources using broadcast waves can be achieved.

[0478] Although each embodiment of the present disclosure has been described above, the technical scope of the present disclosure is not limited to each embodiment as it is in the above embodiment, and various changes can be made without departing from the gist of the present disclosure. In addition, components covering different embodiments and modified examples can be appropriately combined.

[0479] Furthermore, the effects in each embodiment described in this specification are merely examples and not limitations, and other effects may be obtained.

[0480] The present technology may also have the following configurations. (1)

[0482] A communication device, comprising:

[0483] an acquisition unit configured to acquire first information for communication that has used the first frequency band from a second frequency band different from the first frequency band, the first frequency band being a license-exempt frequency band capable of mixing a plurality of communication methods; and

[0484] The communication control unit is configured to control communication of a predetermined communication method that has used the first frequency band based on the first information. (2)

[0486] The communication device according to (1), wherein the first information includes timing information that enables sharing of timing with other communication devices that use the first frequency band in a communication method different from the predetermined communication method, and

[0487] The communication control unit controls communication in a predetermined communication method that has used the first frequency band based on the timing information. (3)

[0489] The communication device according to (2), wherein the timing information is information broadcast using the second frequency band. (4)

[0491] The communication device according to (3), wherein the timing information is information broadcasted from the terrestrial broadcasting station device using the second frequency band, and is virtual satellite transmission information generated by imitating information transmitted from a navigation satellite. (5)

[0493] The communication device according to (4), wherein the virtual satellite transmission information is a virtual pulse-per-second (PPS) signal imitating a GPS signal transmitted from a navigation satellite, and is decoded to become a pulse-per-second (PPS) signal. (6)

[0495] The communication device according to (4),

[0496] The acquiring unit acquires second information for time measurement or timing measurement sent from the navigation satellite, and

[0497] The communication control unit controls communication of a predetermined communication method that has used the first frequency band based on any one of the timing information and the second information included in the first information. (7)

[0499] The communication device according to (6), wherein the communication control unit

[0500] When the predetermined number of navigation satellites can be captured, controlling communication of the predetermined communication method that has used the first frequency band based on the second information, and

[0501] When the predetermined number of navigation satellites cannot be captured, communication of the predetermined communication method that has used the first frequency band is controlled based on the timing information included in the first information. (8)

[0503] The communication device according to any one of (1) to (7),

[0504] The first information includes control information for instructing the communication device on control of communication, and

[0505] The communication control unit controls communication of a predetermined communication method that has used the first frequency band based on the control information. (9)

[0507] The communication device according to (8), wherein the control information includes stop information for stopping the communication device from transmitting using the radio wave of the first frequency band. (10)

[0509] The communication device according to (8), wherein the control information includes scheduling information for scheduling the communication device to have transmitted using radio waves of the first frequency band. (11)

[0511] The communication device according to (2),

[0512] wherein the first information includes control information for controlling communication of the communication device, and

[0513] The communication control unit controls communication of a predetermined communication method that has used a first frequency band based on the timing information and the control information. (12)

[0515] The communication device according to (11),

[0516] wherein the second frequency band includes a second band composed of a plurality of frequency bands and a first band different from the second band, a bandwidth of the first band being wider than a bandwidth of one of the plurality of frequency bands constituting the second band, and

[0517] The acquisition unit acquires first information including timing information from the first band. (13)

[0519] The communication device according to any one of (1) to (12), wherein the first frequency band is a frequency band capable of performing a specific compact power-saving radio. (14)

[0521] The communication device according to any one of (1) to (13), wherein the first frequency band is a frequency band of 920 MHz. (15)

[0523] The communication device according to any one of (1) to (14), wherein the second frequency band is a VHF-high frequency band. (16)

[0525] The communication device according to any one of (1) to (15), wherein the predetermined communication method is a communication method of low power wide area (LPWA) communication. (17)

[0527] A communication method, comprising:

[0528] acquiring, from a second frequency band different from the first frequency band, first information for communication that has used the first frequency band, the first frequency band being a license-exempt frequency band capable of mixing a plurality of communication methods; and

[0529] Communication of a predetermined communication method that has used the first frequency band is controlled based on the first information. (18)

[0531] A communications program that enables a computer to be used as:

[0532] an acquisition unit configured to acquire first information for communication that has used the first frequency band from a second frequency band different from the first frequency band, the first frequency band being a license-exempt frequency band capable of mixing a plurality of communication methods; and

[0533] The communication control unit is configured to control communication of a predetermined communication method that has used the first frequency band based on the first information. (19)

[0535] A sending device, comprising:

[0536] an acquisition unit configured to acquire first information used by a communication device that has communicated using a predetermined communication method in a first frequency band to control the communication, the first frequency band being a license-exempt frequency band in which a plurality of communication methods can be mixed; and

[0537] The sending unit is configured to send the first information using a second frequency band different from the first frequency band. (20)

[0539] A communication system includes: a communication device configured to perform communication using a first frequency band, the first frequency band being a license-free frequency band capable of mixing multiple communication methods; and a transmission device configured to transmit information to the communication device.

[0540] The sending device includes

[0541] a transmitting unit configured to transmit, using a second frequency band different from the first frequency band, first information used by the communication device in controlling communication of a predetermined communication method that has used the first frequency band, and

[0542] The communication device includes

[0543] an acquiring unit configured to acquire first information from the second frequency band, and

[0544] The communication control unit is configured to control communication of a predetermined communication method that has used the first frequency band based on the first information.

[0545] [Reference Symbol List]

[0546] 1, 2, 3, 4 Communication Systems

[0547] 10 Server Equipment

[0548] 20 base station equipment

[0549] 30 Broadcasting Station Equipment

[0550] 40 terminal equipment

[0551] 11 Communication Unit

[0552] 12, 22, 32, 43 storage units

[0553] 13, 24, 34, 46 control units

[0554] 21, 41 wireless communication unit

[0555] 23, 33, 44 Network communication units

[0556] 31 signal processing unit

[0557] 35, 42 satellite receiving units

[0558] 45 Input and Output Units

[0559] 341, 461 acquisition unit

[0560] 342 Sending Unit

[0561] 462 Communication Control Unit

[0562] 31a, 31b, 31c, 31d virtual satellite modules

[0563] 41a, 42a front end

[0564] 41b upconverter

[0565] 42c downconverter

[0566] 41d Subchannel Demodulator

[0567] 41e LPWA transmitter

[0568] 46b AB selector

[0569] 200LPWA receiver

[0570] 300, 300A, 300B control information transmitter

[0571] 400, 400B LPWA sending terminal

[0572] 310 Virtual Satellite Signal Creation Device

Claims

1. A communication device, comprising: an acquisition unit configured to acquire, from a second frequency band different from a first frequency band, first information for communication that has used the first frequency band, the first frequency band being a license-exempt frequency band capable of mixing a plurality of communication methods; as well as a communication control unit configured to control communication of a predetermined communication method that has used the first frequency band based on the first information, wherein the first information includes timing information that enables timing to be shared with other communication devices that use the first frequency band in a communication method different from the predetermined communication method, wherein the communication control unit controls the communication of the predetermined communication method that has used the first frequency band based on the timing information, wherein the timing information is information broadcast using the second frequency band, and The timing information is information broadcast from a terrestrial broadcasting station device using the second frequency band, and is virtual satellite transmission information generated by imitating information transmitted from a navigation satellite.

2. The communication device according to claim 1, wherein the virtual satellite transmission information is a virtual PPS signal that imitates a PPS signal transmitted from the navigation satellite, and is decoded to become a PPS signal.

3. The communication device according to claim 1, wherein the acquiring unit acquires second information for time measurement or timing measurement sent from the navigation satellite, and The communication control unit controls communication of a predetermined communication method that has used the first frequency band based on any one of the timing information included in the first information and the second information.

4. The communication device according to claim 3, wherein the communication control unit When a predetermined number of navigation satellites can be captured, controlling communication of the predetermined communication method that has used the first frequency band based on the second information, and When the predetermined number of navigation satellites cannot be captured, communication of the predetermined communication method that has used the first frequency band is controlled based on timing information included in the first information.

5. The communication device according to claim 1, wherein the first information includes control information for instructing the communication device to control communication, and The communication control unit controls communication of the predetermined communication method that has used a first frequency band based on the control information. 6 . The communication device according to claim 5 , wherein the control information includes stop information for stopping transmission already performed by the communication device using radio waves in the first frequency band. 7 . The communication device according to claim 5 , wherein the control information includes scheduling information for scheduling transmission by the communication device using radio waves of the first frequency band.

8. The communication device according to claim 1, wherein the first information includes control information for controlling communication of the communication device, and The communication control unit controls communication of the predetermined communication method that has used a first frequency band based on the timing information and the control information.

9. The communication device according to claim 8, wherein the second frequency band includes a second band composed of a plurality of frequency bands and a first band different from the second band, the bandwidth of the first band being wider than the bandwidth of one of the plurality of frequency bands constituting the second band, and The acquisition unit acquires the first information including the timing information from the first band. 10 . The communication device according to claim 1 , wherein the first frequency band is a frequency band capable of performing a specific small power-saving radio. The communication device according to claim 1 , wherein the first frequency band is a 920 MHz frequency band.

12. The communication device according to claim 1, wherein the second frequency band is a VHF (Very High Frequency) band. 13 . The communication device according to claim 1 , wherein the predetermined communication method is a communication method of Low Power Wide Area (LPWA) communication.

14. A communication method, comprising: acquiring, from a second frequency band different from a first frequency band, first information for communication that has used the first frequency band, the first frequency band being a license-exempt frequency band capable of mixing a plurality of communication methods; and controlling communication of a predetermined communication method that has used the first frequency band based on the first information, wherein the first information includes timing information that enables timing to be shared with other communication devices that use the first frequency band in a communication method different from the predetermined communication method, wherein the communication method further comprises controlling the communication of the predetermined communication method that has used the first frequency band based on the timing information, wherein the timing information is information broadcast using the second frequency band, and The timing information is information broadcast from a terrestrial broadcasting station device using the second frequency band, and is virtual satellite transmission information generated by imitating information transmitted from a navigation satellite.

15. A computer program product comprising instructions which, when executed by a processor, cause the processor to: acquiring, from a second frequency band different from a first frequency band, first information for communication that has used the first frequency band, the first frequency band being a license-exempt frequency band capable of mixing a plurality of communication methods; and controlling communication of a predetermined communication method that has used the first frequency band based on the first information, wherein the first information includes timing information that enables timing to be shared with other communication devices that use the first frequency band in a communication method different from the predetermined communication method, wherein the instructions, when executed by the processor, further cause the processor to control communication of the predetermined communication method that has used the first frequency band based on the timing information, wherein the timing information is information broadcast using the second frequency band, and The timing information is information broadcast from a terrestrial broadcasting station device using the second frequency band, and is virtual satellite transmission information generated by imitating information transmitted from a navigation satellite.

16. A sending device, comprising: an acquisition unit configured to acquire first information used by a communication device that performs communication in a predetermined communication method that has used a first frequency band, which is a license-exempt frequency band capable of mixing a plurality of communication methods, in controlling the communication; as well as a sending unit configured to send the first information using a second frequency band different from the first frequency band, wherein the first information includes timing information that enables sharing of timing with other communication devices that use the first frequency band in a communication method different from the predetermined communication method, so that the communication device controls communication in the predetermined communication method that has used the first frequency band based on the timing information, wherein the timing information is information broadcast using the second frequency band, and The timing information is information broadcast from a terrestrial broadcasting station device using the second frequency band, and is virtual satellite transmission information generated by imitating information transmitted from a navigation satellite.

17. A communication system comprising: a communication device configured to perform communication that has used a first frequency band, the first frequency band being a license-exempt frequency band capable of mixing a plurality of communication methods; and a sending device configured to send information to the communication device, The sending device includes a transmitting unit configured to transmit, using a second frequency band different from the first frequency band, first information used by the communication device in controlling communication in a predetermined communication method that has used the first frequency band, wherein the first information includes timing information that enables sharing of timing with other communication devices that use the first frequency band in a communication method different from the predetermined communication method, wherein the timing information is information broadcast using the second frequency band, and wherein the timing information is information broadcast from a terrestrial broadcast station device using the second frequency band and is information transmitted by a virtual satellite generated by imitating information transmitted from a navigation satellite, and The communication device includes an acquiring unit configured to acquire the first information from the second frequency band, and A communication control unit configured to control communication of a predetermined communication method that has used the first frequency band based on the first information, wherein the communication control unit controls communication of the predetermined communication method that has used the first frequency band based on the timing information.

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