JP6658688B2 - Communication module - Google Patents

Description

  The present invention relates to a communication module. In particular, the present invention relates to a communication module used in a wireless communication network system.

  In a wireless communication network system, a relay device that relays wireless communication between nodes is often used.

  For example, Patent Literature 1 discloses a relay transmission / reception device that relays wireless transmission / reception performed between a base station and a mobile station. The relay transmission / reception device of Patent Document 1 receives a first signal transmitted / received to / from a base station, a second signal transmitted / received to / from a mobile station, a frequency of the first signal, A frequency conversion unit that converts the frequency of the first signal and / or the second signal so that the frequencies of the two signals are different, and a transmission unit that transmits the first signal and the second signal output from the frequency conversion unit Prepare.

JP 2011-182007 A

  However, the relay transmission / reception device disclosed in Patent Document 1 is a device suitable for a mobile communication network system that performs high-speed, large-capacity data communication. For this reason, it is difficult for the relay transmission / reception device disclosed in Patent Document 1 to support wireless communication technologies such as so-called LPWA (Low Power Wide Area), and the Internet of Things (IoT) or the Machine to Machine (M2M). It is not easy to introduce it into wireless communication network systems used in technical fields such as.

  In a wireless communication network system used in a technical field such as IoT or M2M, an installation location of a terminal device as an end point is often fixed for a long time. For this reason, in the wireless communication network system used in these technical fields, when the terminal device is installed in a place where the radio wave reception environment is not good, it is difficult to reliably transmit data acquired by the terminal device to the base station, Communication reliability may be reduced.

  Therefore, in a wireless communication network system used in a technical field such as IoT or M2M, it is desired to realize a relay function of wireless communication with a simple configuration and secure communication reliability.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to solve the above-described problems. That is, an example of an object of the present invention is to provide a communication module that realizes a relay function of wireless communication with a simple configuration and can ensure communication reliability of a communication system.

A communication module according to one aspect of the present invention is a communication module for performing wireless communication between a base station and a terminal device conforming to an LPWA (Low Power Wide Area) wireless communication standard , wherein the terminal device When data transmitted to the base station from the terminal communication module provided in the terminal device is transmitted according to a first communication protocol using radio waves of a predetermined frequency band specified by the base station Receiving the data transmitted from the terminal communication module according to the first communication protocol, and receiving the received data using the first communication protocol using radio waves in the same frequency band as the predetermined frequency band. wherein by sending to the base station according to the second communications protocol different, and the terminal device so as to be regarded as integral with the terminal communication module base Relays wireless communication between the first communication protocol, without advance mutual authentication operation between the terminal communication module, a specific communication format predetermined between said terminal communication module And a communication protocol for performing wireless communication using a specific communication channel, wherein the second communication protocol uses a communication channel specified by the base station and uses a communication channel defined by channel hopping to perform wireless communication. This is a communication protocol for performing communication .

  Preferably, the communication module is configured with substantially the same hardware as the terminal communication module, and is configured to be operable in a plurality of operation modes, and the plurality of operation modes are controlled by the terminal device. A first operation mode for receiving the data transmitted from the unit, transmitting the received data according to the first communication protocol, and receiving the data according to the first communication protocol; A second operation mode for transmitting the data to the base station in accordance with the second communication protocol, at least, the second operation mode is set, between the terminal device and the base station Relay wireless communication.

  Preferably, the communication module includes a first protocol stack, which is a program related to wireless communication implemented according to the first communication protocol, and a program related to wireless communication implemented according to the second communication protocol. A second protocol stack, and switching between the first protocol stack and the second protocol stack to perform wireless communication with the terminal communication module and wireless communication with the base station. Switch between communications.

  Preferably, when the communication module receives the data transmitted from the terminal communication module, the communication module switches the previously set first protocol stack to the second protocol stack, and transmits the received data to the base station. And transmitting the data to the base station and switching the second protocol stack to the first protocol stack.

  Preferably, in the communication module, the specific communication format in the first communication protocol is a communication format having a frame structure in which a predetermined fixed value and a predetermined fluctuation value are added to the data, The specific communication channel in the first communication protocol is a communication channel specified by a predetermined frequency included in the predetermined frequency band.

  Preferably, in the communication module, the predetermined fixed value includes information uniquely determined for the terminal communication module and information uniquely determined for the communication module; The variation value includes a sequence number that sequentially varies each time the data is transmitted.

  Preferably, the communication module communicates the data with the control unit of the terminal device, the terminal communication module, and the base station based on a common command system.

  Means for solving the problem of the present invention can also be expressed as follows.

  That is, a communication system according to one aspect of the present invention is a communication system that performs wireless communication between a terminal device and a base station, and is provided in the terminal device and transmitted from the terminal device to the base station. A first communication module that transmits data using a radio wave of a predetermined frequency band specified by the base station, and the terminal device and the base station are provided at a distance from the first communication module. A second communication module for receiving the transmitted data and transmitting the data to the base station using radio waves in the same frequency band as the predetermined frequency band, wherein the first communication module and the second communication module Wireless communication is performed between the first communication module and the second communication module so that the two are considered as one.

  Preferably, in the communication system, wireless communication performed between the first communication module and the second communication module is performed according to a first communication protocol, and the second communication module and the base station Is performed according to a second communication protocol different from the first communication protocol.

  Preferably, in the communication system, the first communication module and the second communication module are configured by substantially the same hardware, and configured to be operable in a plurality of operation modes. The first operation mode of receiving the data transmitted from the control unit of the terminal device and transmitting the received data according to the first communication protocol, and the first operation mode of the first device A second operation mode for receiving the data according to a communication protocol and transmitting the received data to the base station according to the second communication protocol, wherein the first communication module and the second communication module Is set in one of the first operation mode and the second operation mode, whereby the first communication module or the second Operatively configured as a signal module.

  Preferably, in the communication system, the second communication module is mounted according to the second communication protocol, and a first protocol stack is a program related to wireless communication mounted according to the first communication protocol. A second protocol stack, which is a program related to wireless communication, wherein the wireless communication between the first communication module and the base station is performed by switching between the first protocol stack and the second protocol stack. Switching between wireless communication performed with a station.

  Preferably, in the communication system, when the second communication module receives the data transmitted from the first communication module, switches the previously set first protocol stack to the second protocol stack, When the received data is transmitted to the base station and the data is transmitted to the base station, the second protocol stack is switched to the first protocol stack.

  Preferably, in the communication system, the first communication protocol is a wireless communication using a specific communication format and a specific communication channel predetermined between the first communication module and the second communication module. The second communication protocol is a communication protocol that performs wireless communication using a communication format specified by the base station and using a communication channel determined by channel hopping.

  Preferably, in the communication system, the specific communication format in the first communication protocol is a communication format having a frame structure in which a predetermined fixed value and a predetermined fluctuation value are added to the data, The specific communication channel in the first communication protocol is a communication channel specified by a predetermined frequency included in the predetermined frequency band.

  Preferably, in the communication system, the predetermined fixed value includes information uniquely determined for the first communication module, and information uniquely determined for the second communication module, The predetermined variation value includes a sequence number that sequentially varies each time the data is transmitted.

  Preferably, in the communication system, the control unit of the terminal device, the first communication module, the second communication module, and the base station perform the data communication based on a common command system. .

  A communication module according to one aspect of the present invention can realize a relay function of wireless communication with a simple configuration, and can secure communication reliability of a communication system.

Some embodiments of the present invention are described below, by way of example only, with reference to the accompanying drawings.
It is a figure showing the composition of the communication system which has the communication module concerning the embodiment of the present invention. FIG. 3 is a block diagram illustrating a functional configuration of a terminal device, a relay device, and a base station. It is a figure for explaining operation mode of a communication module and a terminal communication module. FIG. 3 is a diagram for explaining a communication format used in a first communication protocol. FIG. 3 is a diagram for explaining a communication channel used in a first communication protocol. FIG. 5 is a diagram for explaining a communication channel used in a second communication protocol. FIG. 3 is a diagram illustrating a flow of a data communication process performed in the communication system.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The embodiments described below show some examples of the present invention and do not limit the content of the present invention. Further, all configurations and operations described in each embodiment are not necessarily essential as configurations and operations of the present invention. The same components are denoted by the same reference numerals, and redundant description will be omitted.

[Configuration of Communication System and Communication Module]
FIG. 1 is a diagram showing a configuration of a communication system 1 having a communication module 31 according to an embodiment of the present invention.

  The communication system 1 is a wireless communication network system. Specifically, the communication system 1 is a system capable of wireless communication over a wide area with low power consumption. The communication system 1 is a system that supports wireless communication technology such as LPWA and is applicable to technical fields such as IoT and M2M. The communication system 1 may be a system based on a wireless communication standard such as SIGFOX (registered trademark), LoRa (registered trademark), or NB-IoT (Narrow Band-Internet of Things).

  The frequency band of the radio wave used for the wireless communication of the communication system 1 is a predetermined frequency band specified by a wireless communication standard such as the above-mentioned SIGFOX. The predetermined frequency band is a band that does not require a license for its use, and may be, for example, a 920 MHz band in Japan. The communication distance of the communication system 1 may be, for example, several kilometers to 100 kilometers.

  The communication system 1 includes a terminal device 2, a relay device 3, a base station 4, and a cloud server 5, as shown in FIG. The terminal device 2, the relay device 3, the base station 4, and the cloud server 5 may be connected in a connection mode that forms a star topology.

  In the communication system 1, data acquired by the terminal device 2 is transmitted to the base station 4 via the relay device 3 and collected by the cloud server 5 connected to the base station 4. The data collected by the cloud server 5 is analyzed and processed by various application programs of the cloud server 5, and is used for providing various services. The communication system 1 may include various devices other than the devices illustrated in FIG.

  In the present embodiment, a process performed by the communication system 1 to transmit data acquired by the terminal device 2 to the base station 4 connected to the cloud server 5 is also simply referred to as a “data communication process”.

  FIG. 2 is a block diagram illustrating a functional configuration of the terminal device 2, the relay device 3, and the base station 4.

The terminal device 2 is a device that acquires various data transmitted to the base station 4 to be collected by the cloud server 5. The terminal device 2 is an end point of the communication system 1. The terminal device 2 may be a sensor device that acquires various data by detecting a predetermined physical quantity or the like.
As shown in FIG. 2, the terminal device 2 includes a data acquisition unit 21, a terminal control unit 22, and a terminal communication module 23.

  The data acquisition unit 21 acquires various data transmitted from the terminal device 2 to the base station 4. The data acquisition unit 21 may be various sensors that detect a predetermined physical quantity and the like. The data acquired by the data acquisition unit 21 may be detection values of various sensors. The data acquisition unit 21 is connected to the terminal control unit 22 and outputs the acquired data to the terminal control unit 22.

  The terminal control unit 22 includes a processor, controls the components of the terminal device 2 in an integrated manner, and executes control processing for implementing various functions of the terminal device 2. The terminal control unit 22 receives the data output from the data acquisition unit 21. The terminal control unit 22 transmits the received data to the terminal communication module 23.

  The terminal communication module 23 is a wireless communication module provided in the terminal device 2. The terminal communication module 23 is a communication module for performing wireless communication between the terminal device 2 and the relay device 3.

  As shown in FIG. 2, the terminal communication module 23 is connected to the terminal control unit 22 and includes an IF (interface) circuit unit 24 that receives data transmitted from the terminal device 2 to the base station 4 from the terminal control unit 22. Prepare. The terminal communication module 23 includes a wireless communication circuit unit 25 that includes an antenna and transmits data transmitted from the terminal device 2 to the base station 4. Further, the terminal communication module 23 includes a storage unit 26 in which various programs and the like necessary for the control unit 27 to execute various processes are stored. Further, the terminal communication module 23 includes a control unit 27 that controls each component of the terminal communication module 23 in an integrated manner.

  Data communication between the terminal control unit 22 and the terminal communication module 23 is performed based on a predetermined command system. The predetermined command system may be a general-purpose command system related to serial data communication, such as an AT command. The predetermined command system may be a command system specified in the wireless communication standard of the base station 4 such as the above-mentioned SIGFOX.

  That is, the terminal control unit 22 adds data transmitted from the terminal device 2 to the base station 4 to a transmission command included in a predetermined command system, and transmits the transmission command to the IF circuit unit 24 of the terminal communication module 23. The control unit 27 of the terminal communication module 23 analyzes the command received by the IF circuit unit 24. Then, the control unit 27 determines that the command received by the IF circuit unit 24 is a transmission command, and that the data included in the transmission command is data to be transmitted to the base station 4. The control unit 27 adds the type information of the transmission command to the data included in the transmission command, outputs the data to the wireless communication circuit unit 25, and causes the wireless communication circuit unit 25 to transmit the data.

  This predetermined command system is shared by the entire communication system 1 as well as the data communication between the terminal control unit 22 and the terminal communication module 23. That is, wireless communication is performed between the terminal communication module 23 and a communication module 31 of the relay device 3 described later, and between the communication module 31 and the base station 4 based on the predetermined command system. In other words, the terminal control unit 22, the terminal communication module 23, the communication module 31, and the base station 4 perform data communication based on a common command system.

The relay device 3 is a device that relays wireless communication between the terminal device 2 and the base station 4. The relay device 3 is installed at a point away from the terminal device 2 and the base station 4.
The relay device 3 includes a communication module 31 as shown in FIG.

The communication module 31 is a wireless communication module provided in the relay device 3. The communication module 31 is a communication module for performing wireless communication between the terminal device 2 and the relay device 3 and wireless communication between the relay device 3 and the base station 4.
The communication module 31 includes an IF circuit 32, a wireless communication circuit unit 33, a storage unit 34, and a control unit 35, as shown in FIG.

  The communication module 31 may include an SoC (System on a Chip) including an IF circuit unit 32, a wireless communication circuit unit 33, a storage unit 34, and a control unit 35, and a printed circuit board on which the SoC is mounted. The printed board may be provided with a printed antenna or a connector used for connection with an external antenna. Note that the communication module 31 is configured by substantially the same hardware as the terminal communication module 23.

  The IF circuit section 32 is an IF circuit for connecting the communication module 31 to its peripheral circuits. The peripheral circuit of the communication module 31 is, for example, a control unit of the relay device 3 or the like. The IF circuit section 32 may be an IF circuit corresponding to a serial data communication format. The IF circuit unit 32 may be, for example, an IF circuit compatible with a UART (Universal Asynchronous Receiver-Transmitter) format.

  The wireless communication circuit section 33 includes an antenna and receives data transmitted from the terminal communication module 23 according to a predetermined first communication protocol. In addition, the wireless communication circuit unit 33 transmits data received according to the first communication protocol to the base station 4 according to a predetermined second communication protocol.

  The first communication protocol is a communication protocol in wireless communication between the terminal communication module 23 and the communication module 31. The second communication protocol is a communication protocol in wireless communication between the communication module 31 and the base station 4. The first communication protocol and the second communication protocol are different communication protocols.

  Since the wireless communication between the terminal device 2 and the base station 4 is relayed by the communication module 31, the communication module 31 and the terminal communication module 23 are regarded as one from the viewpoint of the terminal control unit 22 and the base station 4. Can be done. From such a viewpoint, in the present embodiment, the first communication protocol can be expressed as an internal communication protocol, and the second communication protocol can be expressed as an external communication protocol. The details of the first communication protocol and the second communication protocol will be described later with reference to FIGS.

  The storage unit 34 stores various programs and various setting information necessary for the control unit 35 to execute various processes, data temporarily generated as a result of the various processes, and the like.

  In particular, in the storage unit 34, firmware for realizing the communication function of the communication module 31 is stored in advance. The firmware includes a first protocol stack, which is a program related to wireless communication implemented according to the first communication protocol, and a second protocol stack, which is a program related to wireless communication implemented according to the second communication protocol. Prepare. Further, the firmware includes a program related to serial data communication with a peripheral circuit. Further, the firmware includes a program for operating the communication module 31 in a plurality of operation modes. This firmware is substantially the same as the firmware incorporated in the terminal communication module 23 to realize the communication function of the terminal communication module 23. Details of the plurality of operation modes will be described later with reference to FIG.

  The control unit 35 includes a processor, controls the components of the communication module 31 as a whole, and executes various processes for implementing various functions of the communication module 31.

  In particular, when performing wireless communication between the terminal communication module 23 and the communication module 31, the control unit 35 controls the operation of the wireless communication circuit unit 33 based on the first protocol stack stored in the storage unit 34. I do. When performing wireless communication between the communication module 31 and the base station 4, the control unit 35 controls the operation of the wireless communication circuit unit 33 based on the second protocol stack stored in the storage unit 34. Further, the control unit 35 controls each component of the communication module 31 including the wireless communication circuit unit 33 and the IF circuit unit 32 so that the communication module 31 operates in the operation mode set at the time of activation.

  The base station 4 is a wireless communication facility connected to a cloud server 5 which is a back end of the communication system 1. The base station 4 may be a wireless communication facility that conforms to the above-described wireless communication standards such as SIGFOX. The base station 4 performs wireless communication with the communication module 31 according to the second communication protocol. When receiving the data transmitted from the communication module 31, the base station 4 transfers the received data to the cloud server 5 and causes the cloud server 5 to collect the data.

[Operation mode of communication module]
FIG. 3 is a diagram for explaining operation modes of the communication module 31 and the terminal communication module 23.

  As described above, the communication module 31 is configured by substantially the same hardware as the terminal communication module 23. The firmware stored in the storage unit 34 of the communication module 31 is substantially the same as the firmware incorporated in the terminal communication module 23. The firmware of the communication module 31 can operate the communication module 31 in a plurality of operation modes.

  That is, although the communication module 31 and the terminal communication module 23 are configured by common hardware and firmware, they are configured to be operable in a plurality of operation modes. The plurality of operation modes include first to fourth operation modes.

  The first operation mode is an operation mode for realizing the communication function of the communication module provided in the terminal device 2. Specifically, the first operation mode performs serial data communication with the terminal control unit 22 of the terminal device 2 and performs wireless communication with the communication module 31 of the relay device 3 according to the first communication protocol. This is the operation mode to be performed. That is, the first operation mode is an operation mode in which data transmitted from the terminal control unit 22 is received and the received data is transmitted according to the first communication protocol.

  The second operation mode is an operation mode for realizing the communication function of the communication module provided in the relay device 3. Specifically, the second operation mode performs wireless communication with the terminal communication module 23 of the terminal device 2 according to the first communication protocol, and performs wireless communication with the base station 4 according to the second communication protocol. This is an operation mode for performing communication. That is, the second operation mode is an operation mode in which data transmitted from the terminal communication module 23 is received according to the first communication protocol, and the received data is transmitted to the base station 4 according to the second communication protocol. .

  The third operation mode is an operation mode of a communication module provided in the terminal device 2 and performing wireless communication directly with the base station 4 without going through the relay device 3. Specifically, the third operation mode is an operation mode in which serial data communication is performed with the terminal control unit 22 of the terminal device 2 and wireless communication is performed with the base station 4 according to the second communication protocol. is there. That is, the third operation mode is an operation mode in which data transmitted from the terminal control unit 22 is received, and the received data is transmitted to the base station 4 according to the second communication protocol.

  The fourth operation mode is an operation mode of a communication module provided in a relay device that further relays wireless communication between the relay device 3 and the base station 4. Specifically, in the fourth operation mode, wireless communication is performed with the communication module 31 of the relay device 3 according to the second communication protocol, and wireless communication with the base station 4 is performed according to the second communication protocol. This is an operation mode in which That is, the fourth operation mode is an operation mode in which data transmitted from the communication module 31 is received according to the second communication protocol, and the received data is transmitted to the base station 4 according to the second communication protocol.

  Each of the communication module 31 and the terminal communication module 23 is configured to perform any one of the first to fourth operation modes according to the state of the data input / output port when the power is turned on or when the hardware is reset. Is set. Then, it is determined whether each of the communication module 31 and the terminal communication module 23 operates as the communication module 31 or the terminal communication module 23 according to the set operation mode. Specifically, each of the communication module 31 and the terminal communication module 23 is determined to operate as the terminal communication module 23 when the first operation mode is set, and the communication module 31 is set when the second operation mode is set. It is determined to operate as.

  As described above, the communication module 31 and the terminal communication module 23 are configured with common hardware and firmware, but can operate to realize different communication functions according to the operation mode set at the time of startup. .

[First Communication Protocol and Second Communication Protocol]
As described above, the first communication protocol is a communication protocol in wireless communication between the terminal communication module 23 and the communication module 31. The second communication protocol is a communication protocol in wireless communication between the communication module 31 and the base station 4. The first communication protocol and the second communication protocol are specified to use radio waves in the above-mentioned predetermined frequency band, and substantially the same frequency band is used. However, the first communication protocol and the second communication protocol use at least different communication formats and communication channels.

  The first communication protocol is a communication protocol that performs wireless communication between the terminal communication module 23 and the communication module 31 using a predetermined specific communication format and a specific communication channel. On the other hand, unlike the specific communication format of the first communication protocol, the second communication protocol is a communication protocol that performs wireless communication using a communication channel determined by channel hopping.

  FIG. 4 is a diagram for explaining a communication format used in the first communication protocol. FIG. 4A shows a frame structure defined in the physical layer of the first communication protocol. FIG. 4B shows the configuration of the application data shown in FIG.

  In the first communication protocol, frames having substantially the same structure are used when transmitting from the terminal communication module 23 to the communication module 31 and when transmitting from the communication module 31 to the terminal communication module 23. Then, in both the transmission from the terminal communication module 23 and the transmission from the communication module 31, the “data” field shown in FIG. 4B is transmitted from the terminal device 2 to the base station 4. Data is stored. That is, when responding to the reception of the data transmitted from the terminal communication module 23, the communication module 31 returns the received data to the terminal communication module 23.

  In the first communication protocol, the “command type” field shown in FIG. 4B includes the transmission command described above in both the transmission from the terminal communication module 23 and the transmission from the communication module 31. Is stored. That is, when responding to the reception of the data transmitted from the terminal communication module 23, the communication module 31 returns the type information of the received command to the terminal communication module 23.

  The communication format used in the first communication protocol is, as shown in FIGS. 4A and 4B, a predetermined fixed value for data transmitted from the terminal device 2 to the base station 4. And a communication format having a frame structure to which predetermined fluctuation values are added.

  Specifically, the predetermined fixed value added to the data transmitted from the terminal device 2 to the base station 4 is set in the “source address” and “destination address” fields shown in FIG. The information to be stored corresponds.

  At the time of transmission from the terminal communication module 23 to the communication module 31, the lower 32 bits of the MAC (Media Access Control address) address of the terminal communication module 23 may be stored in the "source address" field. The MAC address of the terminal communication module 23 is information uniquely determined for the terminal communication module 23. If the transmission from the terminal communication module 23 to the communication module 31 is a unicast method, the lower 32 bits of the MAC address of the communication module 31 may be stored in the “destination address” field. The MAC address of the communication module 31 is information uniquely determined for the communication module 31. Alternatively, a value uniquely determined in advance may be stored in the “destination address” field if the transmission from the terminal communication module 23 to the communication module 31 is a broadcast method.

  When transmitting from the communication module 31 to the terminal communication module 23, the lower 32 bits of the MAC address of the communication module 31 may be stored in the “source address” field. The “destination address” field may store the lower 32 bits of the MAC address in the terminal communication module 23 to which the response is sent.

  As described above, the predetermined fixed value added to the data transmitted from the terminal device 2 to the base station 4 is information uniquely determined for the terminal communication module 23 and uniquely determined for the communication module 31. Information.

  Further, the predetermined fluctuation value added to the data transmitted from the terminal device 2 to the base station 4 corresponds to information stored in a “sequence number” field shown in FIG. 4B. The “sequence number” field may store a sequence number that sequentially changes each time data transmitted from the terminal device 2 to the base station 4 is transmitted from the terminal communication module 23 or the communication module 31.

  In the communication system 1, data transmitted from the terminal device 2 to the base station 4 is transmitted from the terminal communication module 23 to the communication module 31 and transmitted from the communication module 31 to the base station 4 in packet units. That is, in the present embodiment, a packet is one wireless communication performed between the terminal communication module 23 and the communication module 31 or one wireless communication performed between the communication module 31 and the base station 4. It is a unit of data transmitted in communication. In other words, the packet is a transmission unit of data transmitted from the terminal device 2 to the base station 4. The sequence number may be a number that is incremented each time this packet is transmitted from the transmission source.

  As described above, the predetermined fluctuation value added to the data transmitted from the terminal device 2 to the base station 4 includes a sequence number that fluctuates sequentially each time the data is transmitted in the terminal communication module 23 or the communication module 31. .

  On the other hand, the communication format used in the second communication protocol is a communication format specified by the wireless communication standard of the base station 4 such as the above-mentioned SIGFOX. The above-described information uniquely determined for the terminal communication module 23 and the communication module 31 is not included in the frame used in the second communication protocol. Also, the frame used in the second communication protocol does not include the above-described sequence number that sequentially changes each time data transmitted from the terminal device 2 to the base station 4 is transmitted in the communication module 31.

  FIG. 5 is a diagram for explaining a communication channel used in the first communication protocol. FIG. 6 is a diagram for explaining a communication channel used in the second communication protocol.

  5 and 6, the horizontal axis represents time, and the vertical axis represents frequency. 5 and 6, a white square indicates a packet, and a gray square extending in the left-right direction of the drawing indicates a communication channel. FIG. 5 schematically shows a communication channel used for transmission from the terminal communication module 23 to the communication module 31 (relay device 3). FIG. 6 schematically shows a communication channel used at the time of transmission from the communication module 31 to the base station 4.

  In the first communication protocol, as shown in FIG. 5, a predetermined specific communication channel is used. This specific communication channel is a communication channel specified by a predetermined frequency included in the above-described predetermined frequency band. In the first communication protocol, the specific communication channel is used both when transmitting from the terminal communication module 23 to the communication module 31 and when transmitting from the communication module 31 to the terminal communication module 23. That is, when transmitting data (packet) to the communication module 31, the terminal communication module 23 transmits using the specific communication channel. Then, also in the communication module 31, when responding to the reception of the data (packet) transmitted from the terminal communication module 23, the transmission is performed using this specific communication channel.

  On the other hand, the communication channel used in the second communication protocol may be a communication channel specified by the wireless communication standard of the base station 4 such as the above-mentioned SIGFOX. That is, in the second communication protocol, as shown in FIG. 6, unlike the first communication protocol, a communication channel determined by channel hopping is used. The communication channel defined by the channel hopping is a plurality of communication channels defined by a plurality of frequencies randomly selected from a plurality of frequencies included in the above-described predetermined frequency band.

  In the second communication protocol, at the time of transmission from the communication module 31 to the base station 4, substantially the same data (packet) is continuously loaded within a transmission cycle on a plurality of communication channels randomly selected by channel hopping. As a result, data (packet) is transmitted. At this time, the base station 4 does not need to switch the communication channel used for reception in synchronization with the communication module 31. The base station 4 may set all communication channels included in the predetermined frequency band as communication channels used for reception. Thus, in the second communication protocol, even when data (packet) is transmitted from the communication module 31 at an arbitrary timing, the data (packet) is appropriately received by the base station 4.

  In the second communication protocol, the communication channel used when transmitting from the base station 4 to the communication module 31 is a communication channel determined by channel hopping, similarly to when transmitting from the communication module 31 to the base station 4. No need. In the second communication protocol, a communication channel used for transmission from the base station 4 to the communication module 31 may be a communication channel predetermined with the base station 4. That is, when responding to the reception of the data (packet) transmitted from the communication module 31, the base station 4 may transmit using the received communication channel as it is, or may use another predetermined communication channel. May be transmitted.

[Data communication processing]
FIG. 7 is a diagram illustrating a flow of the data communication process performed in the communication system 1.

  As described above, in the communication system 1, data transmitted from the terminal device 2 to the base station 4 is transmitted from the terminal communication module 23 to the communication module 31 and transmitted from the communication module 31 to the base station 4 in packet units. You. In the present embodiment, a packet transmitted from the terminal communication module 23 to the communication module 31 or a packet transmitted from the communication module 31 to the base station 4 is simply referred to as a “transmission packet”. Similarly, in the present embodiment, in order to respond to the reception of the transmission packet, a packet transmitted from the communication module 31 to the terminal communication module 23 or a packet transmitted from the base station 4 to the communication module 31 is simply referred to as “ Also called a "response packet."

  In step 701, the communication module 31 sets the first protocol stack in advance so that a transmission packet from the terminal communication module 23 can be received. Then, when a certain time has elapsed from the start, the communication module 31 enters a sleep state and waits until a transmission packet from the terminal communication module 23 is received. It should be noted that the terminal communication module 23 also enters a sleep state and waits until a transmission command from the terminal control unit 22 is received after a predetermined time has elapsed from the start. Thereby, the power consumption of the communication module 31 and the terminal communication module 23 can be reduced, and the cost and the life of the communication system 1 can be reduced.

  In step 702, upon receiving the data output from the data acquisition unit 21, the terminal control unit 22 creates a transmission command including the received data.

  In step 703, the terminal control unit 22 transmits the created transmission command to the terminal communication module 23.

  In step 704, upon receiving the command transmitted from the terminal control unit 22, the terminal communication module 23 analyzes the received command. Then, when determining that the received command is a transmission command, the terminal communication module 23 creates a transmission packet in a specific communication format used in the first communication protocol.

  In step 705, the terminal communication module 23 transmits the created transmission packet to the communication module 31 through a specific communication channel used in the first communication protocol.

  In step 706, upon receiving the transmission packet from the terminal communication module 23, the communication module 31 creates a response packet in a specific communication format used in the first communication protocol. As described above with reference to FIGS. 4A and 4B, the response packet includes data included in the transmission packet from the terminal communication module 23, command type information, and a predetermined Is composed of a fixed value, a variable value, and the like.

  In step 707, the communication module 31 transmits the created response packet to the terminal communication module 23 through a specific communication channel used in the first communication protocol.

  In step 708, upon receiving the response packet from the communication module 31, the terminal communication module 23 analyzes the received response packet. Specifically, the terminal communication module 23 compares the transmission packet transmitted in step 705 with the response packet received in step 708. If the data included in both packets, the command type information, and the predetermined fixed value and the variable value do not match or have a predetermined correspondence relationship, the terminal communication module 23 determines that the transmission packet It is determined that the data has not been transmitted to S.31. In this case, the terminal communication module 23 retransmits or recreates the transmission packet as a retry process. On the other hand, if the data included in both packets, the command type information, and the predetermined fixed value and the variable value match or have a predetermined correspondence relationship, the terminal communication module 23 determines that the transmission packet is normally transmitted to the communication module. 31 is determined to have been transmitted.

  In step 709, when the terminal communication module 23 determines that the transmission packet has been transmitted normally, it transmits an ACK (acknowledgment) response to the terminal control unit 22.

  In step 710, upon receiving the ACK response from the terminal communication module 23, the terminal control unit 22 determines that the transmission packet has been successfully transmitted to the communication module 31.

  In step 711, the communication module 31 switches the setting of the protocol stack from the first protocol stack to the second protocol stack. Specifically, the communication module 31 switches to the second protocol stack after the transmission of the response packet performed in step 707 is completed.

  In step 712, the communication module 31 creates a transmission packet in the communication format of the second communication protocol. That is, the communication module 31 creates a transmission packet in a predetermined communication format for wireless communication with the base station 4.

  In step 713, the communication module 31 transmits the created transmission packet to the base station 4 through the communication channel of the second communication protocol. That is, the communication module 31 transmits to the base station 4 on a communication channel determined by channel hopping. Specifically, the communication module 31 transmits substantially the same transmission packet to a plurality of communication channels determined by channel hopping continuously, thereby transmitting the transmission packet to the base station 4.

  In step 714, the communication module 31 switches the setting of the protocol stack from the second protocol stack to the first protocol stack. Specifically, the communication module 31 switches to the first protocol stack after the transmission of the transmission packet performed in step 713 is completed. Then, the communication module 31 waits in the sleep state until receiving the transmission packet from the terminal communication module 23.

  In step 715, upon receiving the transmission packet from the communication module 31, the base station 4 transfers the packet to the cloud server 5 and causes the cloud server 5 to collect the packet. The cloud server 5 has a function of determining duplicate transmission packets, and can delete unnecessary transmission packets even when a plurality of substantially the same transmission packets are transmitted.

  In steps 716 and 717, the terminal control unit 22 performs the same processing as in steps 702 and 703, and transmits a transmission command to the terminal communication module 23.

  In steps 718 and 719, the terminal communication module 23 performs the same processing as in steps 704 and 705, and transmits a transmission packet to the communication module 31. At this time, if the communication module 31 is transmitting the transmission packet to the base station 4, the transmission packet transmitted from the terminal communication module 23 in step 719 is not received by the communication module 31. In this case, the response packet from the communication module 31 is not transmitted to the terminal communication module 23 either. Accordingly, the terminal communication module 23 cannot determine that the transmission packet has been normally transmitted to the communication module 31, and does not transmit an ACK response to the terminal control unit 22.

  In step 720, the terminal control unit 22 confirms that an ACK response has not been received even after a predetermined time has elapsed from step 716.

  In step 721, the terminal control unit 22 determines that the transmission packet has not been successfully transmitted to the communication module 31.

  In step 722, the terminal control unit 22 retransmits or re-creates the transmission command as the retry processing in step 716.

  As described above, the communication module 31 switches between the first protocol stack and the second protocol stack, thereby performing the wireless communication performed with the terminal communication module 23 and the wireless communication performed with the base station 4. Can be switched. Thereby, the communication module 31 can relay the wireless communication between the terminal device 2 and the base station 4.

[Effects]
As described above, in the communication system 1 according to the present embodiment, the terminal communication module 23 transmits a transmission packet including data transmitted from the terminal device 2 to the base station 4 to the communication module 31 according to the first communication protocol. Send. The communication module 31 receives the transmission packet transmitted from the terminal communication module 23 according to the first communication protocol, and transmits the packet to the base station 4 according to a second communication protocol different from the first communication protocol.

  In the first communication protocol and the second communication protocol, the frequency bands of radio waves used in each of the first communication protocol and the second communication protocol are the same as the above-described predetermined frequency band. The predetermined frequency band is a frequency band specified by the wireless communication standard of the base station 4 such as the above-mentioned SIGFOX. For this reason, the communication module 31 does not make the terminal control unit 22 and the base station 4 aware of the presence or absence of the relay function, so that the terminal device 2 and the base station 4 can be regarded as integral with the terminal communication module 23. Wireless communication can be relayed. Accordingly, when the terminal device 2 is installed in a place where the radio wave reception environment is not good, the communication module 31 can transmit the data acquired by the terminal device 2 without changing the design of the terminal device 2 and the base station 4. Can be reliably transmitted to the base station 4. Therefore, the communication module 31 according to the present embodiment can realize the relay function of the wireless communication in the communication system 1 with a simple configuration, and can improve the communication reliability of the communication system 1.

  In particular, the communication module 31 according to the present embodiment performs data communication with the terminal control unit 22, the terminal communication module 23, and the base station 4 based on a common command system. The common command system may be a command system specified in the wireless communication standard of the base station 4. For this reason, the communication module 31 can be easily introduced into a wireless communication network system used in a technical field such as IoT or M2M without changing the specifications of the terminal device 2 and the base station 4. Therefore, the communication module 31 according to the present embodiment can more easily realize the communication system 1 having high communication reliability.

  Further, the communication module 31 according to the present embodiment is configured by substantially the same hardware as the terminal communication module 23, and operates in the respective operation modes of the communication module 31 and the terminal communication module 23 according to the setting at the time of startup. It is configured to be operable. Therefore, the communication module 31 is not configured as a dedicated product for realizing the relay function of the wireless communication performed in the communication system 1, but is configured as a general-purpose product indispensable for the wireless communication performed in the communication system 1. obtain. Therefore, since the communication module 31 according to the present embodiment can significantly reduce the cost, the communication system 1 having high communication reliability can be more easily realized.

  Further, the communication module 31 according to the present embodiment includes a first protocol stack and a second protocol stack. By switching between them, the communication module 31 can switch between wireless communication performed with the terminal communication module 23 and wireless communication performed with the base station 4. For this reason, the communication module 31 can relay wireless communication between the terminal device 2 and the base station 4 without requiring a complicated hardware configuration. Therefore, the communication module 31 according to the present embodiment can more easily realize the communication system 1 having high communication reliability.

  Further, in the communication module 31 according to the present embodiment, a specific communication format and a specific communication channel are used in the first communication protocol in the wireless communication with the terminal communication module 23. Therefore, when performing wireless communication with the terminal communication module 23, the communication module 31 can smoothly ensure communication reliability without performing a mutual authentication operation such as pairing with the terminal communication module 23. it can. Therefore, the communication module 31 according to the present embodiment can achieve both communication reliability and convenience even with a simple configuration.

  Further, in the communication module 31 according to the present embodiment, the specific communication format used in the first communication protocol has information and a sequence number uniquely determined for the terminal communication module 23 and the communication module 31 added thereto. It has a frame structure. For this reason, in the communication module 31 and the terminal communication module 23, the validity of the received transmission packet can be easily confirmed, so that the occurrence of a transmission error can be suppressed. This leads to suppression of data transmitted from the terminal device 2 to the base station 4 being transmitted from the terminal control unit 22 more than necessary. Thereby, the communication module 31 can suppress the congestion of the communication system 1 and the power consumption of the terminal device 2. Therefore, the communication module 31 according to the present embodiment can further achieve both communication reliability and convenience even with a simple configuration.

  Further, in the communication module 31 according to the present embodiment, the second communication protocol in the wireless communication with the base station 4 uses a communication format and a communication channel specified by the wireless communication standard of the base station 4. The communication channels are a plurality of communication channels included in the above-mentioned predetermined frequency band and randomly selected by channel hopping. The communication module 31 can transmit to the base station 4 by placing substantially the same transmission packet on the plurality of communication channels. Therefore, the communication module 31 according to the present embodiment can suppress occurrence of collision of transmission packets when transmitting to the base station 4. In addition, among the plurality of transmission packets transmitted to the base station 4, unnecessary unnecessary transmission packets are deleted by the cloud server 5 connected to the base station 4. Therefore, the communication module 31 according to the present embodiment can further improve communication reliability even with a simple configuration.

  Note that the communication system 1 is not limited to a system including only the terminal communication module 23 operating in the first operation mode and the communication module 31 operating in the second operation mode. That is, the communication system 1 may include a communication module operating in the third operation mode and a communication module operating in the fourth operation mode, in addition to the terminal communication module 23 and the communication module 31. Further, the communication module 31 and the terminal communication module 23 may be configured to be operable in a test mode in addition to the first to fourth operation modes. The test mode is an operation mode in which a transmission cycle of a transmission command and a transmission packet and a baud rate can be set.

[Others]
In the above-described embodiment, the communication module 31 corresponds to an example of a “communication module” described in the claims. The base station 4 corresponds to an example of a “base station” described in the claims. The terminal device 2 corresponds to an example of “terminal device” described in the claims. The terminal communication module 23 corresponds to an example of a “terminal communication module” described in the claims. The terminal control unit 22 corresponds to an example of the “terminal device control unit” described in the claims.

  It will be apparent to those skilled in the art that the above-described embodiments can be applied to each other's technologies, including modifications.

  The descriptions above are intended to be illustrative, not limiting. Thus, it will be apparent to one skilled in the art that modifications may be made to the embodiments of the present invention without departing from the scope of the claims set out below.

  The terms used in the specification and claims are to be interpreted as non-limiting terms. For example, the term “comprising” should be interpreted as “not limited to what is described as including”. The term "comprising" should be interpreted as "not limited to what is described as comprising." The term “comprising” should be interpreted as “not limited to what is described as having”.

DESCRIPTION OF SYMBOLS 1 Communication system 2 Terminal device 3 Relay device 4 Base station 5 Cloud server 21 Data acquisition unit 22 Terminal control unit 23 Terminal communication module 24 IF circuit unit 25 Wireless communication circuit unit 26 Storage unit 27 Control unit 31 Communication module 32 IF circuit unit 33 Wireless communication circuit unit 34 Storage unit 35 Control unit

Claims (7)

A communication module for performing wireless communication between a base station and a terminal device according to a wireless communication standard of LPWA (Low Power Wide Area) ,
Data transmitted from the terminal device to the base station is transmitted from a terminal communication module provided in the terminal device using radio waves of a predetermined frequency band specified by the base station according to a first communication protocol. Then, the data transmitted from the terminal communication module is received in accordance with the first communication protocol, and the received data is transmitted to the first data using radio waves in the same frequency band as the predetermined frequency band . By transmitting to the base station according to a second communication protocol different from the communication protocol ,
Relaying wireless communication between the terminal device and the base station so as to be regarded as integral with the terminal communication module ,
The first communication protocol does not perform a mutual authentication operation with the terminal communication module in advance, but uses a specific communication format and a specific communication channel predetermined with the terminal communication module to perform wireless communication. Communication protocol for communication,
The second communication protocol is a communication protocol that performs wireless communication using a communication format specified by the base station and using a communication channel determined by channel hopping.
Communication module. The terminal communication module is configured with substantially the same hardware, and is configured to be operable in a plurality of operation modes,
The plurality of operation modes include:
A first operation mode for receiving the data transmitted from the control unit of the terminal device and transmitting the received data in accordance with the first communication protocol;
A second operation mode for receiving the data according to the first communication protocol and transmitting the received data to the base station according to the second communication protocol;
At least
By setting the second operation mode, relays wireless communication between the terminal device and the base station,
The communication module according to claim 1 . A first protocol stack that is a program related to wireless communication implemented according to the first communication protocol, and a second protocol stack that is a program related to wireless communication implemented according to the second communication protocol,
By switching between the first protocol stack and the second protocol stack, switching between wireless communication performed with the terminal communication module and wireless communication performed with the base station,
Communication module according to claim 1 or claim 2. Upon receiving the data transmitted from the terminal communication module, switch the previously set first protocol stack to the second protocol stack, transmit the received data to the base station,
When transmitting the data to the base station, switching the second protocol stack to the first protocol stack;
The communication module according to claim 3 . The specific communication format in the first communication protocol is a communication format having a frame structure in which a predetermined fixed value and a predetermined fluctuation value are added to the data,
The specific communication channel in the first communication protocol is a communication channel specified by a predetermined frequency included in the predetermined frequency band,
The communication module according to claim 1 . The predetermined fixed value includes information uniquely determined for the terminal communication module, and information uniquely determined for the communication module,
The predetermined change value includes a sequence number that sequentially changes each time the data is transmitted,
The communication module according to claim 5 . The control unit of the terminal device, the terminal communication module and the base station, perform the communication of the data based on a common command system,
Communication module according to any one of claims 1 to 6.