JP2021121070A - Wireless communication unit and wireless network system using the same - Google Patents

Abstract

To provide a wireless communication unit that can smoothly transmit and receive important information such as emergency information even when communication traffic between the wireless communication unit and a specific wireless communication unit is congested.SOLUTION: There is provided, in an EPC functional part, an inter-unit bandwidth controller which adjusts and controls a communication bandwidth of each inter-downstream unit wireless bearer for the connection of relay wireless communication parts of downstream units to a wireless base station part such that the more the number of relay wireless communication parts, the narrower the communication bandwidth, depending on the number of the relay wireless communication parts of the downstream units connected simultaneously to the wireless base station part. Thus, when a plurality of the downstream units is connected and a communication load of a specific wireless communication unit increases, communication traffic can be allowed to have a margin in consideration of the transmission and reception of emergency information etc. by reducing a set bandwidth of an inter-unit wireless bearer between the downstream units and the specific wireless communication unit.SELECTED DRAWING: Figure 1

Description

The present invention relates to a wireless communication unit for performing wireless network communication with a mobile terminal, can easily realize a cooperative operation between a plurality of units, and can be suitably used for covering a wide area. The present invention relates to a wireless communication unit and a wireless network system using the wireless communication unit.

For example, in a high-speed communication standard based on the 3GPP specifications, for example, in an LTE (Long Term Evolution) or WiMAX (Worldwide Interoperability for Microwave Access) wireless communication network, an EPC (Evolved Packet Core) accommodating the wireless communication access network is included in the area. It is essential to construct, and the wireless base station to which the mobile terminal is connected receives transmission / reception control of IP packets via the EPC. On the other hand, with the spread of mobile terminals such as mobile phones, smartphones, and tablet PCs, areas where EPCs and wireless base stations are not infrastructure-developed, such as areas at sea, depopulated areas, or areas where communication functions have been lost due to disasters, etc. ( In the following, it is also referred to as "wireless non-developed area"), and there is an increasing demand for using mobile terminals.

In order to meet such demands, for example, Patent Document 1 proposes a composite wireless communication unit in which a wireless base station and an EPC functional unit are integrated. By installing such a wireless communication unit in the above-mentioned wireless non-developed area, a small-scale communicable area is constructed by the wireless base station unit included in the unit, and the EPC function unit in the unit controls communication. By doing so, it becomes possible to perform wireless communication between a plurality of mobile terminals connected to the wireless base station unit. However, the communication area that can be covered by one wireless communication unit is narrow, and the communication capacity is also limited. In this case, it is conceivable to arrange multiple wireless communication units in a wireless non-maintenance area, but communication cooperation between the units is not considered, and communication between mobile terminals connected to different composite devices is not possible. , Has the drawback. Further, when the communication traffic in the area becomes excessive, such as when the number of connected mobile terminals increases or when a large amount of data such as video data is transmitted / received, there is a problem that problems such as congestion are likely to occur.

Therefore, Patent Documents 2 to 7 disclose a configuration in which a plurality of wireless communication units are linked and communication traffic from a mobile terminal is distributed and transferred to each wireless communication unit. Specifically, FIG. 6 of Patent Document 5 discloses a form via a satellite device as a cooperation path between wireless communication units for offloading communication with a mobile terminal.

Japanese Unexamined Patent Publication No. 2016-12841 Japanese Unexamined Patent Publication No. 2018-137661 Japanese Unexamined Patent Publication No. 2018-137662 Japanese Unexamined Patent Publication No. 2018-137663 JP-A-2018-137664 JP-A-2018-137665 JP-A-2018-137666

Patent Documents 2 to 7 show how a plurality of wireless communication units are interconnected (for example, FIG. 1 of Patent Document 2 and the like). Except for the offload mode via the satellite device described above, no specific disclosure has been made in the literature as to what kind of entity this connection was composed of. However, if it is considered that the wireless communication units are connected by wire, if the wireless communication units are to be distributed and arranged in a relatively wide communication area in the wireless non-developed area, the communication cable connecting the devices will be used. It will be very long. As a result, the signal quality and communication capacity are deteriorated, and a relay device is required to prevent this, and there is a problem that the cost for constructing the connection infrastructure rises. Further, in applications such as trains, automobiles, and ships in which wireless communication units are mounted on mobile bodies, it is physically impossible to connect the wireless communication units with cables. Even if it is considered that wireless communication units are also wirelessly connected to each other, priority is given to sending and receiving highly important information such as emergency disaster information when the amount of communication traffic between specific wireless communication units becomes excessive. No technical consideration has been given to this.

An object of the present invention is that a plurality of wireless communication units can be wirelessly linked by a simple structure, and thus a cooperative operation between the plurality of units can be easily realized, and communication traffic with a specific wireless communication unit can be easily realized. It is an object of the present invention to provide a wireless communication unit capable of smoothly transmitting and receiving important information such as emergency information even when the area is congested, and a wireless network system using the wireless communication unit.

In order to solve the above problems, the wireless communication unit of the present invention is configured to be mounted on a mobile body, and is a wireless communication unit for performing wireless network communication with a mobile terminal. A wireless base station unit that can be connected via a wireless bearer for terminals, an EPC (Evolved Packet Core) function unit that is wiredly connected to the wireless base station unit and functions as a higher-level network control unit for the wireless base station unit, and a wired connection to the EPC function unit. As well as being connected, via the radio base station section of the upstream unit (hereinafter referred to as the upstream radio base station section) and the inter-unit radio bearer on the upstream side (hereinafter referred to as the upstream unit radio bearer), which is another wireless communication unit of the first. The radio base station unit is provided between the relay radio communication unit (hereinafter referred to as the downstream relay radio communication unit) of the downstream unit, which is another second radio communication unit, and the unit on the downstream side. It is possible to connect via a wireless bearer (hereinafter referred to as a wireless bearer between downstream units), and the EPC function unit sends a wireless bearer setting request between downstream units to the wireless base station unit, while the wireless base station unit sets the wireless bearer between downstream units. In response to the request, a wireless bearer between downstream units is constructed together with the downstream relay wireless communication unit. The EPC function unit transmits a terminal wireless bearer setting request to the wireless base station unit, while the wireless base station unit sets the terminal wireless bearer. In response to the request, a wireless bearer for the terminal is constructed together with the mobile terminal, and the relay wireless communication unit issues an upstream unit wireless bearer setting request issued by the upstream unit EPC function unit (hereinafter referred to as the upstream EPC function unit). Upon receiving the request for setting the wireless bearer between the upstream units, the wireless bearer between the upstream units is constructed together with the upstream radio base station unit. It is possible to connect simultaneously via a wireless bearer between downstream units that has a one-to-one correspondence with each other, and further, the EPC function unit can be connected to the radio base station unit at the same time according to the number of relay radio communication units of the downstream unit. A unit that adjusts and controls the communication bandwidth of each downstream unit radio bearer for connecting the relay radio communication unit of these downstream units to the radio base station unit so that the communication bandwidth becomes narrower as the number of relay radio communication units increases. It is characterized by having an inter-bandwidth control unit.

Further, the wireless network system of the present invention is a wireless communication unit that is configured to be mounted on a mobile body and for performing wireless network communication with a mobile terminal, and the mobile terminal uses a wireless bearer for the terminal to perform wireless network communication. A wireless base station unit that can be connected, an EPC (Evolved Packet Core) functional unit that is wiredly connected to the wireless base station unit and functions as a higher-level network control unit for the wireless base station unit, and an EPC functional unit are wiredly connected, and the first Relay wireless communication that can be connected via the wireless base station section of the upstream unit (hereinafter referred to as the upstream wireless base station section), which is another wireless communication unit, and the wireless bearer between units on the upstream side (hereinafter referred to as the wireless bearer between upstream units). The radio base station unit includes a relay radio communication unit (hereinafter referred to as a downstream relay radio communication unit) of a downstream unit, which is another second radio communication unit, and a wireless bearer between units on the downstream side (hereinafter, a downstream unit). It is possible to connect via the inter-wireless bearer), and the EPC function unit transmits the downstream inter-unit radio bearer setting request to the radio base station unit, while the radio base station unit receives the downstream inter-unit radio bearer setting request and the downstream relay radio. A wireless bearer between downstream units is constructed together with the communication unit. The EPC function unit transmits a terminal wireless bearer setting request to the wireless base station unit, while the wireless base station unit receives the terminal wireless bearer setting request together with the mobile terminal. A wireless bearer for a terminal is constructed, and the relay wireless communication unit receives an upstream unit wireless bearer setting request issued by the upstream unit EPC function unit (hereinafter referred to as the upstream EPC function unit), and the upstream unit is connected to the wireless bearer. In response to a wireless bearer setting request, a wireless bearer between upstream units is constructed together with the upstream radio base station unit. In the radio base station unit, the relay radio communication unit of a plurality of downstream units has a one-to-one correspondence with the downstream units. It is possible to connect via the radio bearer between units, and the EPC function unit is a relay radio communication unit of the downstream units according to the number of relay radio communication units of the downstream units that are simultaneously connected to the radio base station unit. It is equipped with an inter-unit bandwidth control unit that adjusts and controls the communication bandwidth of each downstream unit radio bearer for connecting to the radio base station unit so that the communication bandwidth becomes narrower as the number of relay radio communication units increases. It consists of a group of wireless communication units in which a plurality of wireless communication units are arranged, and the group of wireless communication units is such that the base station cells of a pair of wireless communication units adjacent to each other partially overlap each other. A mobile terminal connected by an inter-unit wireless bearer in a stationary relationship and connected to one of the wireless communication unit pairs and a mobile terminal connected to the other are connected to the wireless communication unit pair and the wireless communication unit pair. The downstream unit has a communication bandwidth of 1 among the plurality of wireless communication units, which is set to the bearer between the downstream units of the wireless communication unit to which a plurality of downstream units are connected at the same time while transmitting and receiving IP packets via the bearer. It is characterized in that it is set narrower than the communication bandwidth set in the bearer between downstream units of the wireless communication unit connected to only one.

In the subordinate concept of the wireless communication unit (and wireless network system) of the present invention, the inter-unit bandwidth control unit is a downstream unit-to-unit radio when there is one relay radio communication unit of the downstream unit connected to the radio base station. While setting the communication bandwidth of the bearer to a predetermined first bandwidth, when the number of relay radio communication units of the downstream unit connected to the radio base station is two or more, the communication bandwidth of the downstream unit radio bearer is set to the first. It can be configured to be set to a second bandwidth that is less than one bandwidth. In the radio base station unit, the number of downstream units that can be simultaneously connected via the wireless bearer between downstream units can be set to, for example, 2, but is not limited to this, and may be, for example, 3 or more. When the number of downstream units that can be connected at the same time is, for example, 2, the second bandwidth can be set to, for example, 1/2 of the first bandwidth.

Further, the inter-unit bandwidth control unit uses a predetermined type of user data as specific user data among the user data to be transmitted / received, and the communication bandwidth set in the specific user data is a user of another type. It can be configured to control so that it is secured wider than the data. In this case, the specific user data can be, for example, user selection data that the user has set as the specific user data on the mobile terminal. Further, the specific user data can be, for example, emergency video information.

In the wireless communication unit of the present invention and the wireless network system using the same, relay wireless communication that can be connected to another wireless communication unit on the upstream side, the upstream unit (upstream wireless base station), via the wireless bearer between the upstream units. A part is provided. Further, the wireless base station unit can be connected to the downstream unit (downstream relay wireless communication unit), which is another wireless communication unit on the downstream side, via the wireless bearer between the downstream units. As a result, a plurality of wireless communication units can be connected by a wireless bearer between units, and a wireless network system covering a wider area can be easily constructed by the plurality of wireless communication units. Then, in the present invention, the relay radio communication unit of a plurality of downstream units can be connected to the radio base station unit of each radio communication unit via the downstream unit radio bearer having a one-to-one correspondence with the downstream units. Will be done. That is, since a plurality of downstream units can be connected to one wireless communication unit, the wireless communication unit is not limited to the configuration in which the plurality of wireless communication units are arranged in a linear manner, and the wireless communication between the plurality of downstream units can be performed downstream from one wireless communication unit. It is also possible to adopt a star-shaped unit arrangement that branches the bearer. As a result, the connection topology between the wireless communication units can be set more flexibly, and it is possible to efficiently cover a wide communication area.

Then, depending on the number of relay radio communication units of the downstream units that are simultaneously connected to the radio base station unit in the EPC function unit, the radio between each downstream unit for connecting the relay radio communication unit of those downstream units to the radio base station unit. Since the inter-unit bandwidth control unit is provided to adjust and control the communication bandwidth of the bearer so that the communication bandwidth becomes narrower as the number of relay wireless communication units increases, it is possible to specify by connecting multiple downstream units. When the communication load of wireless communication units increases, the set bandwidth of the wireless bearer between units with those downstream units should be reduced to allow the communication traffic to have a margin in consideration of sending and receiving emergency information, etc. Can be done.

The schematic diagram which shows the concept of the wireless communication unit pair which becomes the structural unit of the wireless network system of this invention. The block diagram which shows the outline of the electrical structure of the wireless communication unit pair of FIG. The block diagram which shows an example of the electric structure of the wireless communication unit of this invention. The block diagram which shows an example of the electric structure of a UE (mobile terminal). Conceptual diagram of IP packet. The figure which conceptually shows the protocol stack of the control plane of 3GPP. The figure which conceptually shows the protocol stack of the user plane of 3GPP. The figure which conceptually shows the channel mapping of the downlink of 3GPP. Similarly, a diagram conceptually showing uplink channel mapping. The conceptual diagram which shows the relationship between a frequency band channel and a resource block. The figure which shows typically an example of the configuration form of the wireless network system of this invention. A communication flow diagram showing an attachment sequence of a relay wireless communication unit of a wireless communication unit to another wireless communication unit on the upstream side. A communication flow diagram showing an attachment sequence to a wireless communication unit of a UE (mobile terminal). The figure explaining the outline of the control which reduces the set communication bandwidth of the wireless bearer between downstream units of the wireless communication unit as a new downstream unit attaches to the wireless communication unit in the middle of a wireless communication network system. The figure which shows the example of the user interface for transmitting a desired video as specific user data in a mobile terminal. The conceptual diagram which shows the setting example of the transmission queue at a normal time. The conceptual diagram which shows the setting example of the transmission queue at the time of bandwidth limitation. The flowchart which shows the processing flow of the bandwidth control program between units. A flowchart showing the processing flow of the terminal application. The flowchart which shows the flow of the packet transmission control processing of a radio base station part.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a schematic diagram showing the concept of a pair of wireless communication units, which is a constituent unit of the wireless network system of the present invention, as an embodiment. The wireless communication unit pair comprises the wireless communication units 1 (A) and 1 (B) having the same configuration according to the embodiment of the present invention (hereinafter, also referred to as wireless communication unit pairs 1 (A) and 1 (B)). Wireless communication with the UE (mobile terminal) 5 is performed according to the communication protocol stack of the method specified by 3GPP (in this embodiment, LTE is used, but other methods such as WiMAX may be used). It is configured as.

The wireless communication units 1 (A) and 1 (B) are installed on the large vessels WS (A) and WS (B), which are mobile bodies, respectively, and are wirelessly connected by an inter-unit wireless bearer 55, which will be described in detail later. The wireless communication units 1 (A) and 1 (B) form cells 50 (A) and 50 (B) to which the UE (mobile terminal) 5 can be connected, respectively. In addition, small vessels FB (eg, fishing boats, tugboats, etc.) are operating around the large vessels WS (A), WS (B) (for example, fishing motherships, tankers, etc.), and cell 50 (A) or cell 50. The crew of the small vessel FB in (B) is carrying the UE 5. The UEs 5 are wirelessly connected to the nearest wireless communication units 1 (A) and 1 (B) by a terminal wireless bearer 57, respectively. The UE 5 may be carried by the crew of the large vessels WS (A) and WS (B). Further, the installation destinations of the wireless communication units 1 (A) and 1 (B) may be a moving body (vehicle or the like) other than a ship, or may be fixedly arranged at a desired installation destination on land, for example.

FIG. 2 shows the functional block configuration of the wireless communication units 1 (A) and 1 (B). The wireless communication units 1 (A) and 1 (B) both have the same electrical configuration. When a plurality of wireless communication units and their components are distinguished from each other in the present specification, the same number is given to the corresponding component, and a capital alphabet in parentheses is given following the number. Shown. On the other hand, when each component is shown without distinguishing between wireless communication units, the uppercase alphabet in parentheses may be omitted. Hereinafter, the reference numerals on the wireless communication unit 1 (A) side will be mainly used, but the wireless communication unit 1 (B) side will also be described as necessary with reference to the corresponding reference numerals. Further, in the drawings attached to the present specification, the arrow line indicating the wireless bearer is indicated by a broken line, and the wired bearer or the electrical connection line is indicated by a solid line or an alternate long and short dash line.

The wireless communication unit 1 (A) includes a wireless base station unit 4 (A) (eNodeB (evolved NodeB)) to which the UE (mobile terminal) 5 can be connected via the terminal wireless bearer 57, and a wireless base station unit 4 (A). It has an EPC (Evolved Packet Core) function unit 3 (A) that is wiredly connected to the radio base station unit 4 (A) and functions as an upper network control unit for the radio base station unit 4 (A). Further, the EPC function unit 3 (A) has an inter-unit radio bearer on the upstream side with respect to the radio base station unit 4 (B) (upstream radio base station unit) of the wireless communication unit 1 (B) (upstream unit) on the upstream side. The relay wireless communication unit 9 (A) that can be connected via 55 (upstream unit wireless bearer) is connected by wire.

On the other hand, the wireless communication unit 1 (B) is wiredly connected to the same wireless base station unit 4 (B) and the wireless base station unit 4 (B), and functions as an upper network control unit for the wireless base station unit 4 (B). The EPC function unit 3 (B) and the relay wireless communication unit 9 (B) connected to the EPC function unit 3 (B) by wire are provided. If another wireless communication unit is arranged on the upstream side of the wireless communication unit 1 (B), the relay wireless communication unit 9 (B) provides an inter-unit wireless bearer to the wireless base station unit of the wireless communication unit. It can be connected via (see FIG. 11). Further, the radio base station unit 4 (B) is a radio between units on the downstream side with respect to the relay radio communication unit 9 (A) (downstream relay radio communication unit) of the radio communication unit 1 (A) (downstream unit) on the downstream side. It is possible to connect via the bearer 55 (wireless bearer between downstream units). That is, the inter-unit wireless bearer 55 becomes an upstream inter-unit wireless bearer when viewed from the wireless communication unit 1 (A), and becomes a downstream inter-unit wireless bearer when viewed from the wireless communication unit 1 (B). The unit-to-unit radio bearer 55 (downstream unit-to-unit radio bearer and upstream unit-to-unit radio bearer) is constructed according to the radio protocol stack of the same method as the terminal radio bearer 57, and in the present embodiment, the LTE radio protocol stack. NS.

In both the wireless communication unit 1 (A) and the wireless communication unit 1 (B), in the wireless base station units 4 (A) and 4 (B), the relay wireless communication units of the plurality of downstream units are the downstream units. It is possible to connect via a wireless bearer between downstream units that has a one-to-one correspondence. In FIG. 2, the relay wireless communication unit 9 (A) of the wireless communication unit 1 (A) is connected to the wireless base station unit 4 (B) of the wireless communication unit 1 (B) by the inter-unit wireless bearer 55 (A). Further, the relay wireless communication unit 9 (C) of the wireless communication unit 1 (C) is connected by the inter-unit wireless bearer 55 (B). That is, in the radio base station unit, the relay radio communication units of a plurality of downstream units can be connected to one radio base station unit at the same time. The wireless communication unit 1 (C) also includes a wireless base station unit 4 (C) and an EPC function unit 3 (C). Further, each of the wireless communication units 1 (A) to 1 (D) has a built-in router 8 and can be connected to an external network 60 (for example, a global public network (Internet)) by, for example, a satellite communication line 61 or the like.

Next, in any of the wireless communication units 1 (A) and 1 (B) (hereinafter, collectively referred to as wireless communication unit 1), the EPC function unit 3 is an MME (Mobility Management) that serves as a gateway on the control plane side. Entity) 2, PCRF (Policy and Charging Rules Function) 10, S-GW (Serving Gateway) 6 as a gateway on the user plane side, EPC function unit 3, and upstream network element of the EPC function unit 3 (here, here. A P-GW (PDN (Packet Data Network) Gateway) 7 that is located at the node of the router 8 and the relay wireless communication unit 9) and manages the IP address toward the upstream network element side (that is, the upstream unit side). Have. Further, a plurality of UEs 5 are wirelessly connected to the wireless base station unit 4 via the terminal wireless bearer 57. On the control plane side, the radio base station unit (eNodeB) 4 is connected to the MME 2 via the S1-MME interface. Further, on the user plane side, the radio base station unit 4 is connected to the S-GW 6 via the S1-U interface. Further, the S-GW 6 is connected to the P-GW 7 via the S5 interface. Further, PCRF is connected to P-GW7 and S-GW6 via Gx interface and Gxc interface, respectively.

The PCRF10 functions as an execution body of the bandwidth setting control (inter-unit bandwidth control) of the inter-unit wireless bearer, which will be described later, and is used as a quality of service (QoS) applied to user data packets sent and received by the user. It serves the function of determining the billing system. The QoS value determined by PCRF10 is determined by the type of QoS value, such as whether or not there is a guarantee, the set bandwidth when there is a bandwidth guarantee, the priority of transmission, the allowable delay time, and the allowable loss rate. It is specified in. The QoS value is notified to P-GW7, S-GW6, and the radio base station unit 4, respectively, and each of these nodes performs QoS control on the user data packet according to the notified QoS value.

FIG. 3 is a block diagram showing an electrical configuration of the wireless communication unit 1. The EPC function unit 3 is mainly composed of microcomputer hardware, and stores CPU 301, RAM 302 as a program execution area, and mask ROM 303 (firmware for peripheral control of microcomputer hardware that does not need to be permanently rewritten; Hereinafter, the same applies), and the bus 306 and the like connecting them to each other. Further, a flash memory 305 is connected to the bus 306, and each of the communication firmware 305a including the LTE protocol stack for EPC and the MME2, S-GW6, and P-GW7 of FIG. 2 using the LTE protocol stack as a platform. The programs of the MME entity 305b, the S-GW entity 305c, the P-GW entity 305d, and the PCRF entity 305i that virtually realize the functions are installed. The PCRF entity 305i includes an inter-unit bandwidth control program 305h for performing inter-unit radio bearer bandwidth control.

Further, the upstream communication interface 304A and the downstream communication interface 304B are connected to the bus 306. The input / output port of the IP packet for P-GW is secured in the upstream communication interface 304A, and the input / output port of the IP packet for S-GW is secured in the downstream communication interface 304B. In the above configuration, the MME2, S-GW6, P-GW7, and PCRF10 shown in FIG. 2 are configured as virtual functional blocks on the computer hardware, but they may be configured by independent hardware logic. ..

The radio base station unit 4 is mainly composed of microcomputer hardware, and includes a CPU 401, a RAM 402 as a program execution area, a mask ROM 403, a transmission queue 415, and a bus 406 connecting them to each other. A flash memory 405 is connected to the bus 406, and communication firmware 405a including an LTE protocol stack for a radio base station is stored therein. Further, a communication interface 404 is connected to the bus 406 with a wireless communication unit 412 for wirelessly connecting to the UE by constructing a wireless bearer for terminals. The communication interface 404 is connected to the downstream communication interface 304B of the EPC function unit 3 by a wired communication bus 31. The transmission queue 415 is composed of a FIFO memory or the like and plays a role of storing IP packets to be wirelessly transmitted in the order of transmission. Normally, a plurality of queue memory areas are provided in accordance with a predetermined priority according to the packet type. It is formed.

The relay wireless communication unit 9 is mainly composed of microcomputer hardware, and includes a CPU 901, a RAM 902 as a program execution area, a mask ROM 903, and a bus 906 connecting them to each other. A flash memory 905 is connected to the bus 906, and a communication firmware 905a including an LTE protocol stack for the relay wireless communication unit and an upstream unit connection switching control program 905b are stored therein. Further, a communication interface 904 is connected to the bus 906 with a wireless communication unit 912 for wirelessly connecting to the upstream wireless base station unit by constructing an inter-unit wireless bearer. The communication interface 904 is connected to the upstream communication interface 304A of the EPC function unit 3 by a wired communication bus 30.

In the relay wireless communication unit 9, the LTE protocol stack for the relay wireless communication unit incorporated in the communication firmware 905a is the same as the protocol stack for the UE (mobile terminal) described later. In other words, the connection procedure of the relay radio communication unit 9 to the upstream radio base station unit is formally the same as the attach sequence, which is the connection procedure of the UE (mobile terminal).

Further, a router 8 that relays transmission / reception of IP packets between the EPC function unit 3 and an external network 60 such as the Internet is connected to the communication bus 30 (that is, the EPC function unit 3 and the relay wireless communication unit 9). A router 8 is provided between and the router 8).

Next, the wireless communication unit 1 includes a detachable secondary battery module 21 (for example, a lithium ion secondary battery module, a nickel hydrogen secondary battery module, etc.), a wireless base station unit 4, an EPC function unit 3, a router 8, and the like. Each functional circuit block of the relay wireless communication unit 9 and the power supply circuit unit 22 that converts the input voltage from the secondary battery module 21 into the drive voltage of each functional circuit block and outputs it are integrated in the portable housing 23. It has an assembled structure. As a result, the wireless communication unit 1 can autonomously procure the drive power supply voltage from the secondary battery module 21, and can be used without problems even in an installation place (for example, at sea) where the external power supply voltage cannot be used such as commercial AC. be. The portable housing 23 is a box type made of metal or reinforced resin. In the example shown in FIG. 3, casters 24C are pushed to the bottom of the portable housing 23 and also to the back for convenience of transportation or movement. A handle 24 for use is provided.

When the output voltage of the secondary battery module 21 drops due to discharge, the secondary battery module 21 is removed from the portable housing 23 and attached to, for example, a commercial AC power supply (not shown) or a dedicated charger connected to a private power generator. It is possible to charge the battery. Further, the power supply circuit unit 22 can also receive an external power supply voltage such as the commercial AC or a centralized power supply unit provided on the mobile body, and can convert and output the drive power supply voltage. Further, it can be configured so that the secondary battery module 21 can be charged by the external power supply voltage. For example, if the power supply circuit unit 22 is receiving power from commercial AC or the like and the power reception is interrupted due to a power failure, the operation of the wireless communication unit 1 can be continued by switching to receiving power from the secondary battery module 21. It can also be configured as follows.

Next, FIG. 4 is a block diagram showing an example of the electrical configuration of the UE (mobile terminal) 5. The UE 5 is configured as a smartphone including the microcomputer 100 as a processing subject. The microcomputer 100 includes a CPU 101, a RAM 102 and a ROM 103 that serve as a program execution area, an input / output unit 104, and a bus 106 that connects them to each other. Further, a flash memory 105 is connected to the bus 106, and an OS (not shown) for constructing an operating environment for the UE 5 and a terminal application 105b or the like are installed therein.

A monitor 109 is connected to the input / output unit 104 via a graphic controller 1091. A touch panel 110 forming an input unit is superposed on the monitor 109, and cooperates with various software operation units (buttons, icons, etc .: see FIGS. 13 to 17) displayed and formed on the monitor 109 to control the operation of the UE 5. Various necessary information can be input. The touch panel 110 is connected to the input / output unit 104 via the touch panel controller 1101. A camera 111 for shooting a still image or a moving image is connected to the input / output unit 104. Further, a wireless communication unit 112 is connected to the bus 106. The UE 5 is wirelessly connected by the wireless communication unit 112 to the wireless base station unit 4 of the wireless communication unit 1 of FIG. 2 via the terminal wireless bearer 57.

In the present embodiment, the terminal application 105b is desired for user data (for example, character string data such as disaster message data, still image data such as photographs, and moving image data) transmitted from the UE (mobile terminal) 5. Is selected by the user as specific user data (user selection data), and the packet of the user data is set as a user packet having a higher transfer priority than other user data.

FIG. 5 is a schematic diagram showing a structure of an IP packet used for data transmission between the UE 5 and the wireless communication unit 1. The IP packet 1300 includes an IP header 1301 and a payload 1302, and a PDU identification number, a data source address 1301a, a destination address 1301b, and the like are written in the IP header 1301.

Further, a ToS (Type of Service) field 1301c is formed in the IP header 1301. The ToS field 1301c defines the transfer priority of the packet and the type of communication, of which the transfer priority is defined by the content of the IP Precedence (or Differetiated Service Code Point) 1301d provided at the beginning of the packet. NS. The larger (that is, higher) IP packet set in this IP Presence 1301d means that the IP packet has a higher transfer priority, and the value of the IP Presence 1301d of the user data packet selected as the specific user data described above. Will be set higher than unselected user data packets.

6 and 7 show the radio protocol stack in the LTE system, FIG. 6 shows the protocol stack in the user plane, and FIG. 7 shows the protocol stack in the control plane. The radio protocol stack is divided into layers 1 to 3 of the OSI reference model, and layer 1 is a PHY (physical) layer. Layer 2 includes a MAC (Medium Access Control) layer, an RLC (Radio Link Control) layer, and a PDCP (Packet Data Convergence Protocol) layer. Layer 3 includes an RRC (Radio Resource Control) layer and a NAS (Non-Access Stratum) layer.

The role of each layer is as follows.
-PHY layer: Performs coding / decoding, modulation / demodulation, antenna mapping / demapping, and resource mapping / demapping. Data and control signals are transmitted between the PHY layer of the UE 5 and the relay radio communication unit 9 and the PHY layer of the radio base station unit (eNodeB) 4 via a physical channel.
-MAC layer: Performs data priority control, retransmission control processing by HARQ, random access procedure, and the like. Data and control signals are transmitted between the MAC layer of the UE 5 and the relay radio communication unit 9 and the MAC layer of the radio base station unit 4 via the transport channel. The MAC layer of the radio base station unit 4 includes a scheduler that determines the transport format (transport block size, modulation / coding method (MCS)) of the upper and lower links and the resource block allocated to the UE 5.

-RLC layer: Data is transmitted to the receiving RLC layer by utilizing the functions of the MAC layer and the PHY layer. Data and control signals are transmitted between the RLC layer of the UE 5 and the RLC layer of the radio base station unit 4 via a logical channel.
-PDCP layer: Compresses / decompresses the header of the PDU, and encrypts / decrypts it.
RRC layer: Defined only in the control plane that handles the control signal. Messages for various settings (RRC messages) are transmitted between the RRC layer of the UE 5 and the RRC layer of the radio base station unit 4. The RRC layer controls logical channels, transport channels and physical channels in response to the establishment, re-establishment and release of radio bearers. If there is a connection (RRC connection) between the RRC of the UE 5 and the RRC of the radio base station unit 4, the UE 5 is in the RRC connected mode, otherwise it is in the RRC idle mode.

The above layers are used in both the control plane and the user plane. On the other hand, only the control plane, the UE 5, the relay radio communication unit 9, and the MME 2 are provided with a NAS layer that performs session management, mobility management, and the like further above the RRC layer. Further, a GTP-U (GPRS (General Packet Radio Service) Tunneling Protocol for User Plane) layer is provided on the user data transmission interface with the EPC function unit 3 side of the radio base station unit 4. The GTP-U layer is for identifying the UE 5 to be connected to or the relay wireless communication unit 9 and the wireless bearer to be used.

Next, FIG. 8 shows downlink channel mapping in the LTE system. Here, the mapping relationship between the logical channel (Downlink Logical Channel), the transport channel (Downlink Transport Channel), and the physical channel (Downlink Physical Channel) is shown. Hereinafter, they will be described in order.
-DTCH (Dedicated Traffic Channel) is an individual logical channel for transmitting data. The DTCH is mapped to a DLSCH (Downlink Shared Channel), which is a transport channel.

-DCCH (Dedicated Control Channel): A logical channel for transmitting individual control information between the UE 5 and the network. The DCCH is used when the UE 5 and the relay radio communication unit 9 have an RRC connection with the radio base station unit 4. The DCCH is mapped to the DLSCH.
CCCH (Common Control Channel): A logical channel for transmission control information between the UE 5 and the relay radio communication unit 9 and the radio base station unit 4. CCCH is used when the UE 5 and the relay radio communication unit 9 do not have an RRC connection with the radio base station unit 4. CCCH is mapped to DLSCH.

-BCCH (Broadcast Control Channel): A logical channel for system information distribution. BCCH is mapped to BCH (Broadcast Channel) or DLSCH which is a transport channel.
-PCCH (Paging Control Channel): A logical channel for notifying changes in paging information and system information. The PCCH is mapped to a transport channel, PCH (Paging Channel).

The mapping relationship between the transport channel and the physical channel is as follows.
-DLSCH and PCH: Mapped to PDSCH (Physical Downlink Shared Channel). DLSCH supports HARQ, link adaptation, and dynamic resource allocation.
-BCH: Mapped to PBCH (Physical Broadcast Channel).

Next, FIG. 9 shows uplink channel mapping in the LTE system. Similar to FIG. 8, the mapping relationship between the logical channel (Downlink Logical Channel), the transport channel (Downlink Transport Channel), and the physical channel (Downlink Physical Channel) is shown. Hereinafter, they will be described in order.

CCCH (Common Control Channel): A logical channel used to transmit control information between the UE 5 and the relay radio communication unit 9 and the EPC function unit 3, and is a logical channel used between the EPC function unit 3 and the radio resource. Used by UE5 that does not have a control (RRC: Radio Resource Control) connection.
-DCCH (Dedicated Control Channel): A one-to-one (point-to-point) bidirectional logical channel, and individual control information between the UE 5 and the relay wireless communication unit 9 and the EPC function unit 3. This is the channel used to send. The dedicated control channel DCCH is used by the UE 5 which has an RRC connection.
DTCH (Dedicated Traffic Channel): A one-to-one bidirectional logical channel, which is a channel dedicated to a specific UE or relay radio communication unit, and is used for transferring user information.

-ULSCH (Uplink Shared Channel): HARQ), dynamic adaptive radio link control, and intermittent transmission (DTX) are supported transport channels.
-RACH (Random Access Channel): A transport channel through which restricted control information is transmitted.

-PUCCH (Physical Uplink Control Channel): Response information (ACK (Acknowledge) / NACK (Negative acknowledge)) for downlink data, downlink radio quality information (CQI: Channel Quality Indicator, and uplink) This is a physical channel used to notify the radio base station unit 4 of a data transmission request (scheduling request: SR).
-PUSCH (Physical Uplink Shared Channel): A physical channel used for transmitting uplink data.
-PRACH (Physical Random Access Channel): A physical channel mainly used for random access preamble transmission for acquiring transmission timing information (transmission timing command) from the UE 5 to the radio base station unit 4. Random access preamble transmission is performed in a random access procedure.

As shown in FIG. 9, in the uplink, the transport channel and the physical channel are mapped as follows. The uplink shared channel ULSCH is mapped to the physical uplink shared channel PUSCH. The random access channel RACH is mapped to the physical random access channel PRACH. The physical uplink control channel PUCCH is used by the physical channel alone. Further, the common control channel CCCH, the dedicated control channel DCCH, and the dedicated traffic channel DTCH are mapped to the uplink shared channel ULSCH.

Next, in the downlink of the LTE system, the UE 5 and the relay radio communication unit 9 wirelessly connect to the radio base station unit 4 by OFDM (Orthogonal Frequency-Division Multiplexing) access (OFDMA). The OFDMA system is characterized as a two-dimensional multiplexed access system in which frequency division multiplexing and time division multiplexing are combined. Specifically, the subcarriers on the frequency axis and the time axis that are orthogonal to each other are divided and allocated to the UE 5, and the subcarriers that are orthogonal to each other on the frequency axis are divided so that the signal of each subcarrier becomes zero (0 point). .. By dividing the subcarriers and assigning them on the frequency axis, one subcarrier can select another subcarrier that is not affected by fading, so that the user is better depending on the wireless environment. There is an advantage that the subcarrier can be used and the radio quality can be maintained.

Then, in the OFDMA method, a resource block (hereinafter, also referred to as RB) defined on a virtual plane extending the frequency axis and the time axis is adopted as a radio resource. As shown in FIG. 10, RB is defined as blocks in which the plane is divided into matrices at 180 kHz / 0.5 msec, and each block has 12 adjacent subcarriers at intervals of 15 kHz on the frequency axis and 12 adjacent subcarriers on the time axis. Includes 1 slot (7 symbols) of the frame. This RB is assigned to the UE 5 and the relay radio communication unit 9 as a set of two (1 msec) adjacent to each other on the time axis. On the other hand, in the uplink of the LTE system, a resource block of the same concept is used as a radio resource except that SC-FDM (Single Career Frequency-Division Multiplexing) access (SC-FDMA) is adopted. In OFDMA, one resource block is divided into 12 subcarriers (bandwidth: 15 kHz) on the frequency axis, whereas SC-FDMA is a single carrier system in which division into subcarriers is not performed.

For example, the allocation of a resource block to a downlink is determined by the following procedure in a normal LTE protocol. The UE 5 and the relay radio communication unit 9 receive the CQI reference signal transmitted from the eNodeB 4 for each defined frequency unit, measure the CQI which is an indicator indicating the reception quality of the downlink channel, and create the CQI information. .. The CQI information represents the reception quality obtained by measurement with two parameters, the coding rate and the frequency utilization efficiency, for each modulation method, and is used from the UE 5 to the eNodeB 4 using the uplink control channel (PUCCH described above). Reported using the CQI index.

The eNodeB 4 is assigned to a wireless bearer with each UE 5 or the relay radio communication unit 9 based on the CQI information notified from the plurality of UEs 5 or the relay radio communication unit 9. By optimally allocating a frequency block having a high received signal level to each UE 5 and the relay radio communication unit 9 according to the contents of the CQI information of each UE 5 and the relay radio communication unit 9, the UE 5 and the relay radio communication unit 9 are allocated. The diversity effect of 9 (multi-user diversity) can be obtained, and the user throughput and the throughput per cell can be improved.

FIG. 11 shows a configuration example of the wireless network system of the present invention when the wireless communication unit 1 having the above configuration is adopted. In the wireless network system, the wireless communication unit groups 1 (A) to 1 (D) are adjacent to each other in a pair of wireless communication units (1 (A) and 1 (B), 1 (B) and 1 (C), 1 ( In a positional relationship in which the base station cells (50 (A) and 50 (B), 50 (B) and 50 (C), 50 (B) and 50 (D)) of B) and 1 (D) partially overlap. , Unit-to-unit wireless bearers 55 (A), 55 (B), 55 (C) are connected. Further, two wireless communication units, specifically, a relay wireless communication unit 9 (A) of the wireless communication unit 1 (A) are provided in the wireless base station unit 4 (B) of the wireless communication unit 1 (B) as an inter-unit wireless bearer. The relay wireless communication unit 9 (D) of the wireless communication unit 1 (D) is connected by the 55 (A), and the relay wireless communication unit 9 (D) of the wireless communication unit 1 (D) is connected by the inter-unit wireless bearer 55 (C). The inter-unit radio bearer 55 (A) and the inter-unit radio bearer 55 (C) are set to the same frequency channel (CH1 in FIG. 11). On the other hand, when viewed from the wireless communication unit 1 (B), the downstream inter-unit wireless bearer 55 (A) and the upstream inter-unit wireless bearer 55 (B) are set to different frequency channels (CH1 and CH2 in FIG. 11). ..

For example, the UE 5 (A) (mobile terminal) connected to one of the wireless communication units to 1 (A) and 1 (B) and the UE 5 (B) (mobile terminal) connected to the other are connected to the wireless communication unit to 1 (mobile terminal). IP packets can be transmitted and received via the inter-unit wireless bearer 55 (A) connecting the wireless communication units (A) and 1 (B) and the wireless communication units 1 to 1 (A) and 1 (B). All of the wireless communication unit groups 1 (A) to 1 (D) may be mounted on the above-mentioned moving body such as a ship or a vehicle, or only some of them may be mounted on the moving body. The remaining items may be fixedly installed in the building or the like.

In FIG. 11, the number of wireless communication units connected by the inter-unit wireless bearers 55 (A), 55 (B), and 55 (C) is three or more (four in FIG. 11). In this case, the UE (mobile terminal) 5 (A) connected to the first wireless communication unit 1 (A) forming one wireless communication unit of the wireless communication unit groups 1 (A) to 1 (D) and wirelessly A second wireless communication unit 1 (C) arranged in the communication unit groups 1 (A) to 1 (D) with an intermediate wireless communication unit 1 (B) separated from the first wireless communication unit 1 (A). UEs (mobile terminals) 5 (C) and 5 (D) connected to 1 (D) send IP packets via the inter-unit wireless bearers 55 (A), 55 (B) and 55 (C). You can send and receive.

In the wireless communication system of the 3GPP specification, any of the plurality of frequency bands specified in the 3GPP is assigned. The assigned frequency band differs depending on the communication method. For example, bands 1, 3, 6, 8, 11, 18, 19, 21, 26, 28, 41 and 42 are used as LTE bands. Each band is divided into a plurality of frequency channels having a predetermined bandwidth, and the EPC function unit 3 selects a predetermined frequency channel for the inter-unit radio bearer 55 and the terminal radio bearer 57 shown in FIG. Will be built. That is, the downstream inter-unit channel, the upstream inter-unit channel, and the terminal side channel are each set as a frequency channel belonging to any of a plurality of bands defined in 3GPP.

In the present embodiment, the EPC function unit 3 fixedly sets the set frequency channel of the (downstream) inter-unit radio bearer 55 to the (downstream) inter-unit channel which is a specific predetermined frequency channel. Further, the terminal-side channel, which is the set frequency channel of the terminal radio bearer 57, is set to the same frequency channel as the (downstream) inter-unit channel. That is, the EPC function unit 3 sets the same frequency channel for the relay wireless communication unit 9 and the mobile terminal 5 of the wireless communication unit 1 on the downstream side for the wireless base station unit 4 directly underneath.

In the configuration of a wireless network system that connects a plurality of wireless communication units 1 (A) to 1 (D) as shown in FIG. 11, the connection topology of the adjacent unit by the inter-unit wireless bearer 55 with the wireless base station unit 4 is large. If it does not change, the radio base station unit 4 to which the relay wireless communication unit 9 of each wireless communication unit 1 is connected is fixed, and the handover process involving frequency channel switching is unnecessary for the relay wireless communication unit 9. Become. Therefore, by fixedly setting the inter-unit wireless bearer 55 to the inter-unit channel, which is one specific frequency channel defined in advance, it is possible to effectively prevent communication interruption due to channel switching of the inter-unit wireless bearer 55. , The stability of IP packet transmission when crossing a plurality of wireless communication units 1 can be significantly improved.

Further, in FIG. 11, cell 50 (A) of the wireless communication unit 1 (A), cell 50 (B) of the wireless communication unit 1 (B), cell 50 (C) of the wireless communication unit 1 (C), and wireless. The cells 50 (D) of the communication unit 1 (D) overlap each other. In this case, for example, the inter-unit channel of the inter-unit wireless bearer 55 (B) connecting the upstream wireless communication unit 1 (C) when viewed from the wireless communication unit 1 (B) is the downstream wireless communication unit 1 (A), The frequency channels are set to be different from the inter-unit channels of the inter-unit radio bearers 55 (A) and 55 (C) to which 1 (D) is connected.

The terminal-side channel is set to the same channel as the downstream unit-to-unit channel among the frequency channels belonging to the same band. For example, when only one band is assigned to the entire wireless network system of FIG. 11, the terminal side channel is a terminal by setting the same channel as the downstream unit-to-unit channel among the frequency channels belonging to the same band. It is possible to make the hardware of the radio base station unit 4 and the relay radio communication unit 9 single-band specifications including the construction of the wireless bearer for use, which contributes to the simplification of the device configuration. The terminal-side channel may be switchably selected from the remaining frequency channels other than those set as the downstream unit-to-unit channel and the upstream-unit-to-unit channel.

Further, in the present embodiment, the band 28 defined in 3GPP is adopted as the same band as described above. The band 28 is set to the VHF band (700 MHz band), which is vacant due to the stoppage of terrestrial analog television broadcasting. Since band 28 is a low frequency band, the communication speed is somewhat slow, so adoption in areas with many terminal subscribers such as urban areas is not being actively promoted, and the usage status of radio wave resources is so tight. Since there is no such thing, smooth connection can be expected. Further, the low frequency band is excellent in the distant reachability of radio waves, and the area (cell) that can be covered by one wireless communication unit can be expanded. In addition, it has the property of being easily connected even if there are underground or obstacles, and it can be said that it is also suitable for constructing the wireless network system of the present invention at sea or in a mine, for example.

Hereinafter, the flow of the attachment sequence of the relay wireless communication unit 9 and the UE 5 will be described with reference to FIGS. 12 and 13. FIG. 12 shows an attachment sequence of the relay wireless communication unit 9. In TS1, an attach request is issued from the relay radio communication unit 9 to the MME 2 via the radio base station unit (eNodeB) 4. By receiving the notification signal periodically output from the eNodeB 4, the relay wireless communication unit 9 can recognize that the user has entered the cell (that is, within the range) of the eNodeB 4, and outputs the attach request to the eNodeB 4. At this time, the IP address of the wireless communication unit is transmitted to the requester. In response to this, the MME2 transmits a bearer setting request to the S-GW 6 on the TS2. The S-GW 6 executes the bearer setting process of the physical line on the S5 interface with the P-GW 7 at the TS3. If the bearer is set, the S-GW 6 transmits a bearer setting response to the MME2 on the TS4.

In TS5, MME2 acquires the channel number used by the requesting unit for the bearer between downstream units in TS5, and in TS6, sends a wireless bearer setting request (attach acceptance) to the radio base station unit 4 with the set channel number (acquired channel). Notify with the number of the adjacent channel). Upon receiving this, the radio base station unit 4 transmits a MIB (Master Information Block) including a set channel number of the radio bearer (inter-unit radio bearer) to be set by the TS 7 to the relay radio communication unit 9. In the TS8, the relay wireless communication unit 9 fixedly sets the inter-unit channel to the set channel number included in the received MIB, and returns the setting completion. In response to this, the radio base station unit 4 notifies the relay radio communication unit 9 of the session start request (attachment acceptance) in the TS9. In TS10, the relay radio communication unit 9 sets the radio bearer between units and returns the session start response to the radio base station unit 4. At TS11, the radio base station unit 4 notifies the MME2 of the session start response.

On the other hand, FIG. 13 shows an attachment sequence of UE 5 (mobile terminal). In TS11', an attach request is issued from the UE 5 to the MME 2 via the radio base station unit (eNodeB) 4. At this time, the IP address of the wireless communication unit is transmitted to the requester. In response to this, the MME2 transmits a bearer setting request to the S-GW 6 on the TS12. The S-GW 6 executes a bearer setting process of a physical line on the S5 interface with the P-GW 7 at TS13. If the bearer is set, the S-GW 6 transmits a bearer setting response to the MME2 on the TS14. The MME 2 determines a set channel number that can be used as a wireless bearer group for terminals according to the process of FIG. Then, the TS16 notifies the radio base station unit 4 of the radio bearer setting request (attachment acceptance) together with the set channel number determined. Upon receiving this, the radio base station unit 4 transmits a MIB (Master Information Block) including a set channel number of the radio bearer (inter-unit radio bearer) to be set by the TS 17 to the UE 5. When there is a relay radio communication unit of another radio communication unit connected to the radio base station unit 4, the set channel number is the same as that of the relay radio communication unit 9.

In TS18, the UE 5 sets the terminal side channel to the set channel number included in the received MIB, and returns the setting completion. In response to this, the radio base station unit 4 notifies the UE 5 of the session start request (attachment acceptance) in TS19. At TS20, the UE 5 sets the radio bearer for the terminal and returns the session start response to the radio base station unit 4. At TS21, the radio base station unit 4 notifies the MME2 of the session start response. As described above, the attach sequence of the UE 5 and the attach sequence of the relay wireless communication unit 9 are basically executed according to the same procedure except for the contents of the frequency channel setting.

Hereinafter, the operation of the characteristic portion of the wireless communication unit 1 of the present invention will be described.
In the state B1 of FIG. 14, the wireless communication unit 1 (C) is connected to the wireless communication unit 1 (B) as an upstream unit, and the wireless communication unit 1 (A) is connected as a downstream unit. Here, the downstream unit connected via the wireless bearer 55 (A) between the downstream units when viewed from the wireless communication unit 1 (B) is only the wireless communication unit 1 (A), and the wireless communication unit 1 (B). The EPC function unit 3 sets the communication bandwidth of the downstream unit-to-unit wireless bearer 55 (A) to a default value (for example, 5 Mbps) by the control operation of the PCRF10 described above. Further, when viewed from the wireless communication unit 1 (C), the downstream unit connected via the wireless bearer 55 (B) between the downstream units is only the wireless communication unit 1 (B), and the EPC of the wireless communication unit 1 (C). The functional unit 3 sets the communication bandwidth of the downstream unit wireless bearer 55 (B) to a default value (first bandwidth: for example, 5 Mbps).

In this state, the new wireless communication unit 1 (D) approaches the wireless communication unit 1 (B), and the relay wireless communication unit 9 requests the wireless base station unit 4 of the wireless communication unit 1 (B) to attach. As a result, as shown in the state B2 of FIG. 14, a new downstream unit wireless bearer 55 (C) is constructed between the wireless communication unit 1 (D) and the wireless communication unit 1 (B). As a result, in the wireless base station unit 4 of the wireless communication unit 1 (B), the relay wireless communication units 9 of the plurality of wireless communication units 1 (A) and 1 (D) have a one-to-one correspondence with the wireless communication units 1. The wireless bearers 55 (C) and 55 (A) between the downstream units are connected at the same time. At this time, the EPC function unit 3 of the wireless communication unit 1 (B) sets the communication bandwidth of the downstream unit wireless bearer 55 (A) and the downstream unit wireless bearer 55 (C) to the default value by the control operation of the PCRF10. Change to a value smaller than (for example, 5 Mbps) (second bandwidth: 2.5 Mbps, which is 1/2 of that in the present embodiment).

The wireless base station unit 4 of the wireless communication unit 1 (B) is a UE (mobile terminal) to which a user data packet is transmitted / received when the two wireless communication units 1 (A) and 1 (D) are connected to each other. The number of 5 increases, and the communication processing load increases. In particular, in the event of an emergency disaster, the user data transmitted by each UE (mobile terminal) 5 includes important information such as images, photographs, and message messages that convey the situation at the disaster site, and is congested. There may be a situation in which smooth transmission / reception is hindered by being buried in user data with general contents in communication traffic. Therefore, as described above, the communication bandwidth of the wireless bearer between downstream units is adjusted and controlled so that the communication bandwidth becomes narrower as the number of relay wireless communication units of the downstream unit simultaneously connected to the wireless base station unit increases. Therefore, it becomes possible to secure a margin in the communication traffic in consideration of the transmission / reception of emergency information and the like.

FIG. 18 shows an example of the processing flow of the inter-unit bandwidth control program 305h (FIG. 3). In S101 and S102, the number of connections (number of attachments) of the downstream unit to the radio base station unit 4 is checked. In the present embodiment, the maximum number of connected downstream units is 2, and in S101, the presence or absence of connection with the first downstream unit is examined. If it is not connected, proceed to S106, check if there is a connection with the second downstream unit in S106, and if it is connected, proceed to S107 to determine the bandwidth (of the inter-unit radio bearer) with the second downstream unit. The normal setting (default value: 5 Mbps) is used. On the other hand, if it is connected to the first downstream unit in S101, the process proceeds to S102 to check whether or not there is a connection with the second downstream unit. If it is not connected, the process proceeds to S105, and the bandwidth (of the radio bearer between units) with the first downstream unit is set to the normal setting (default value: 5 Mbps).

Then, in S101 and S102, if both the first downstream unit (for example, wireless communication unit 1 (A)) and the second downstream unit (for example, wireless communication unit 1 (D)) are connected, S103 / S104. The bandwidth between the two downstream units (of the inter-unit radio bearer) is set to the limit setting (2.5 Mbps each). If it is not completed in S108, the process returns to S101 and the following processing is repeated.

When the radio base station unit 4 of the wireless communication unit 1 (B) transmits a user data packet to the downstream unit, the bandwidth is individually set for each queue memory area of the transmission queue 415 in the bandwidth control by SoC. It is possible, for example, for a queue memory allocated to an IP packet with a high transfer priority, a wider bandwidth is set than for a queue memory allocated to an IP packet with a low transfer priority.

FIG. 16 shows an example of bandwidth setting of the transmission queue 415 when the set bandwidth is the default setting, and the setting (guaranteed) bandwidth of the queue memory number 1 for storing the IP packet having the highest transfer priority is secured at 5 Mbps. The bandwidth of the queue memory number 2 or less for storing IP packets having a lower transfer priority is set to be smaller than that. On the other hand, FIG. 17 shows an example of bandwidth setting of the transmission queue 415 when the set bandwidth is the limit setting, and the set bandwidth to the queue memory of each number is compared with the case of the default setting of FIG. , Both are set low.

Then, in the present embodiment, as described above, by using the terminal application 105b on the UE (mobile terminal) 5 connected to the downstream unit, the user data transmitted from the UE (mobile terminal) 5 is desired. The user selects one as specific user data (user selection data), and the packet of the user data can be set as a user packet having a higher transfer priority than other user data. As shown in FIG. 15, the user selects desired user data and monitors the contents (in FIG. 15, moving image data (emergency video information) obtained by shooting a disaster occurrence situation with, for example, a camera 111). By touching the selection button (a soft button linked with the touch panel 110) EMB displayed on the 109 and displayed on the screen, the user data is selected as specific user data and the transfer priority is increased. It will be transmitted as a user data packet.

The packet of the user data selected as the specific user data by the selection button EMB is transmitted with the setting value indicating the high transfer priority written in the IP presence 1301d of the ToS field 1301c in the IP header 1301. FIG. 19 is a flowchart showing a main part of the processing of the terminal application. In S201, the operation status of the selection button EMB is confirmed, and if there is an operation, the process proceeds to S203, and the ToS field (IP presence 1301d) of the IP packet being transmitted is displayed. ) Is written with a value indicating high priority. On the other hand, if there is no operation, the process proceeds to S204, and a value indicating that the priority is normal is written in the ToS field (IP presence 1301d) of the IP packet being transmitted. When the writing of the value to the IP location 1301d is completed, the packet of the user data is transmitted to the wireless communication unit to which each is connected. If it is not completed in S205, the process returns to S201 and the following processing is repeated.

The wireless communication unit (downstream unit) that has received the packet of the user data performs a process of transferring the packet to the upstream unit according to the flow chart shown in FIG. First, in S301, the packet of the user data is received, and the value of the ToS field (IP precision 1301d) of the header is read. In S302, it is confirmed whether or not the value indicates the high priority setting. If it indicates a high priority setting, the process proceeds to S303, and the packet is stored in the queue memory set to the high priority (for example, the memory of No. 1 in FIGS. 16 and 17). On the other hand, in S302, if the above value does not indicate the high priority setting, the process proceeds to 304, and the queue memory (for example, the number 2 or less in FIGS. 16 and 17) in which the packet is set to the normal priority is set. Store in memory).

As a result, the specific user data selected by the user on the UE (mobile terminal) 5 side has priority over the upper queue memory having a wide bandwidth secured in the radio base station unit 4, as shown in FIGS. 16 and 17. It is stored in, ensuring a smoother transfer environment than other data. In particular, even in the state of FIG. 17 in which the bandwidth is limited, the specific user data can use a wider bandwidth than other data, and even in the state where the bandwidth of the entire radio bearer between units is limited, it is smooth and smooth. It can be transferred at high speed.

Although the embodiments of the present invention have been described above, the present invention is merely an example, and the present invention is not limited thereto.

1 (A), 1 (B) Wireless communication unit 2 MME
3 EPC function unit 4 Wireless base station unit 5 UE (mobile terminal)
6 S-GW
7 P-GW
8 Router 9 Relay wireless communication unit 10 PCRF
21 Rechargeable battery module 22 Power supply circuit unit 23 Portable housing 24 Handle 24C Caster 28 Band 30, 31 Communication bus 50 Communication area 55 Inter-unit wireless bearer 57 Terminal wireless bearer 60 External network 61 Satellite communication line 100 Microcomputer 101 CPU
102 RAM
104 Input / output unit 105 Flash memory 105b Terminal application 106 Bus 109 Monitor 110 Touch panel 111 Camera 112 Wireless communication unit 301 CPU
302 RAM
303 mask ROM
304A Upstream communication interface 304B Downstream communication interface 305 Flash memory 305a Communication firmware 305b MME entity 305c S-GW entity 305d P-GW entity 305h Inter-unit bandwidth control program 305i PCRF entity 306 Bus 401 CPU
402 RAM
403 mask ROM
404 Communication interface 405 Flash memory 405a Communication firmware 406 Bus 412 Wireless communication unit 415 Transmission queue 901 CPU
902 RAM
903 mask ROM
904 Communication interface 905 Flash memory 905a Communication firmware 905b Upstream unit connection switching control program 906 Bus 912 Wireless communication unit 1091 Graphic controller 1101 Touch panel controller 1300 IP packet 1301 IP header 1301a Source address 1301b Destination address 1301c ToS field 1301d IP presence 1302 payload

Claims (8)

A wireless communication unit that is configured to be mounted on a mobile body and for performing wireless network communication with a mobile terminal.
A wireless base station unit to which the mobile terminal can be connected via a wireless bearer for terminals,
An EPC (Evolved Packet Core) function unit that is wiredly connected to the radio base station unit and functions as an upper network control unit for the radio base station unit.
Along with being wiredly connected to the EPC function unit, a wireless base station unit (hereinafter, referred to as an upstream wireless base station unit) of an upstream unit, which is another first wireless communication unit, and a wireless bearer between units on the upstream side (hereinafter, upstream unit). It is equipped with a relay wireless communication unit that can be connected via a wireless bearer).
The radio base station unit includes a relay radio communication unit (hereinafter referred to as a downstream relay radio communication unit) of a downstream unit, which is another second radio communication unit, and a unit-to-unit radio bearer on the downstream side (hereinafter referred to as a downstream unit radio bearer). ) Can be connected via
The EPC function unit transmits a downstream unit-to-unit radio bearer setting request to the radio base station unit, while the radio base station unit receives the downstream unit-to-unit radio bearer setting request and together with the downstream relay radio communication unit, the downstream unit-to-unit radio. It builds a bearer,
The EPC function unit transmits a terminal radio bearer setting request to the radio base station unit, while the radio base station unit constructs the terminal radio bearer together with the mobile terminal in response to the terminal radio bearer setting request. can be,
The relay radio communication unit receives the upstream unit radio bearer setting request issued by the upstream unit EPC function unit (hereinafter referred to as the upstream EPC function unit), and receives the upstream unit radio bearer setting request and receives the upstream unit radio bearer setting request. A radio bearer between the upstream units is constructed together with the radio base station section.
The radio base station unit is such that a plurality of relay radio communication units of the downstream units can be simultaneously connected to the downstream units via a radio bearer between downstream units having a one-to-one correspondence.
Each of the downstream units for connecting the relay radio communication unit of the downstream unit to the radio base station unit according to the number of relay radio communication units of the downstream unit connected to the radio base station unit at the same time. A wireless communication unit comprising a unit-to-unit bandwidth control unit that adjusts and controls the communication bandwidth of an inter-unit wireless bearer so that the communication bandwidth becomes narrower as the number of relay wireless communication units increases. The inter-unit bandwidth control unit sets the communication bandwidth of the downstream unit radio bearer to a predetermined first bandwidth when there is one relay radio communication unit of the downstream unit connected to the radio base station. On the other hand, when the number of relay radio communication units of the downstream unit connected to the radio base station is two or more, the communication bandwidth of the downstream unit radio bearer is set to a second bandwidth smaller than the first bandwidth. The wireless communication unit according to claim 1. The wireless communication unit according to claim 2, wherein the wireless base station unit has two downstream units that can be simultaneously connected via the wireless bearer between the downstream units. The wireless communication unit according to claim 3, wherein the second bandwidth is set to 1/2 of the first bandwidth. Among the user data to be transmitted / received, the inter-unit bandwidth control unit uses a predetermined type of user data as specific user data, and the communication bandwidth set in the specific user data is user data of another type. The wireless communication unit according to any one of claims 1 to 4, which is controlled so as to be secured more widely. The wireless communication unit according to claim 5, wherein the specific user data is user selection data that the user has set as the specific user data on the mobile terminal. The wireless communication unit according to claim 5 or 6, wherein the specific user data is emergency video information. A wireless communication unit that is configured to be mounted on a mobile body and for performing wireless network communication with a mobile terminal, and a wireless base station unit to which the mobile terminal can be connected via a wireless bearer for a terminal, and the above. An EPC (Evolved Packet Core) function unit that is wiredly connected to the wireless base station unit and functions as a higher-level network control unit for the wireless base station unit, and a first separate wireless communication unit that is wiredly connected to the EPC function unit. The radio is provided with a radio base station unit of a certain upstream unit (hereinafter referred to as an upstream radio base station unit) and a relay radio communication unit that can be connected via an inter-unit radio bearer (hereinafter referred to as an upstream unit radio bearer) on the upstream side. The base station unit includes a relay radio communication unit (hereinafter referred to as a downstream relay radio communication unit) of a downstream unit, which is another second radio communication unit, and a unit-to-unit radio bearer on the downstream side (hereinafter referred to as a downstream unit radio bearer). The EPC function unit transmits a request for setting a wireless bearer between downstream units to the wireless base station unit, while the wireless base station unit receives the request for setting a wireless bearer between downstream units and performs the downstream relay wireless communication. The downstream unit wireless bearer is constructed together with the unit, and the EPC function unit transmits a terminal wireless bearer setting request to the wireless base station unit, while the wireless base station unit receives the terminal wireless bearer setting request. The wireless bearer for the terminal is constructed together with the mobile terminal, and the relay wireless communication unit is a request for setting the wireless bearer between upstream units issued by the EPC function unit (hereinafter referred to as the upstream EPC function unit) of the upstream unit. To construct the upstream unit radio bearer together with the upstream radio base station unit in response to the upstream unit radio bearer setting request, the radio base station unit is a relay radio communication unit of a plurality of the downstream units. However, it is possible to connect to these downstream units via a wireless bearer between downstream units that has a one-to-one correspondence, and further, the EPC function unit is a relay radio communication of the downstream unit that is simultaneously connected to the radio base station unit. Depending on the number of units, the communication bandwidth of each of the downstream unit radio bearers for connecting the relay radio communication unit of these downstream units to the radio base station unit is increased as the number of relay radio communication units increases. It consists of a group of wireless communication units in which a plurality of wireless communication units equipped with an inter-unit bandwidth control unit that adjusts and controls so that the bandwidth becomes narrower are arranged.
The wireless communication unit group is connected by the inter-unit wireless bearer in a positional relationship in which base station cells of a pair of wireless communication units adjacent to each other partially overlap each other.
A mobile terminal connected to one of the wireless communication unit pairs and a mobile terminal connected to the other wireless communication unit pair transmit and receive IP packets via the unit-to-unit wireless bearer connecting the wireless communication unit pair and the wireless communication unit pair. And while doing
Of the plurality of wireless communication units, the communication bandwidth set in the bearer between downstream units of the wireless communication unit to which the downstream units are connected at the same time is the wireless communication in which the downstream unit is connected to only one. A wireless network system characterized in that it is set narrower than the communication bandwidth set in the bearer between units downstream of the unit.

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