JP2022017101A - Radio communication unit and radio network system using the same - Google Patents

Abstract

To provide a radio communication unit which enables a plurality of radio communication units to radio cooperate with a simple structure, so as to enable easy cooperative operation among the plurality of units.SOLUTION: Each radio communication unit includes: a relay radio communication part which is connectable through an upstream radio link to a radio base station part (upstream radio base station part) of an upstream node unit which is another radio communication unit on the upstream side. The radio base station part is connectable through a downstream radio link to a relay radio communication part (downstream relay radio communication part) of a downstream node unit which is another radio communication unit on the downstream side. The control plane side of a communication protocol stack side has a configuration in which a radio cooperation protocol layer, which is a new protocol layer, is added to the upper layer side of the transport layer. Cooperation notification information to be used for the implementation and the management control of a radio link (cooperation radio bearer) is incorporated into a cooperation report packet defined in the radio cooperation protocol layer, so as to be transmitted and received among a plurality of radio communication units which are cooperation connection targets.SELECTED DRAWING: Figure 2

Description

The present invention relates to a wireless communication unit for performing wireless network communication with a mobile terminal in accordance with a communication protocol stack defined by 3GPP (Third Generation Partnership Project), and easily realizes a cooperative operation between a plurality of units. The present invention relates to a wireless communication unit that can be used and can be suitably used for covering a wide area, and a wireless network system using the wireless communication unit.

In a wireless network system of a high-speed communication standard based on 3GPP specifications (for example, LTE (Long Term Evolution) or WiMAX (Worldwide Interoperability for Microwave Access)), an EPC (Evolved Packet Core) accommodating a 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 control of transmission / reception 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 maintained in terms of infrastructure, 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 a demand, for example, Patent Document 1 proposes a composite type 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-maintenance area, a communication-capable 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 complex 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 Japanese Unexamined Patent Publication No. 2018-137664 Japanese Unexamined Patent Publication No. 2018-137665 Japanese Unexamined Patent Publication No. 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). However, except for the offload mode via the above-mentioned satellite device, the above-mentioned document does not disclose at all what kind of actual condition the connection is constructed. If you think that the wireless communication units are connected by wire, if you try to distribute the wireless communication units in a reasonably wide communication area in the wireless non-maintenance area, the communication cable connecting the devices will be very difficult. become longer. As a result, there is a problem that the cost for constructing the connection infrastructure rises, for example, the signal quality and the communication capacity are deteriorated, and a relay device is required to prevent the deterioration. 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 each wireless communication unit with a cable.

The subject of the present invention is a wireless communication unit capable of wirelessly linking a plurality of wireless communication units with a simple structure, and thus easily realizing a cooperative operation between the plurality of units, and a wireless network system using the wireless communication unit. Is to provide.

In order to solve the above problems, the wireless communication unit of the present invention is a wireless communication unit for performing wireless network communication with a mobile terminal in accordance with the communication protocol stack defined by 3GPP (Third Generation Partnership Project). A wireless base station unit to which a mobile terminal can be connected via a terminal wireless bearer, an EPC (Evolved Packet Core) functional unit that is connected to the wireless base station unit by wire and functions as an upper network control unit for the wireless base station unit, and an EPC. By being connected to the functional unit by wire and attaching to the wireless base station section (hereinafter referred to as the upstream wireless base station section) of the upstream node unit, which is another wireless communication unit on the upstream side, the upstream linked wireless bearer (hereinafter referred to as the upstream wireless bearer). It is equipped with a relay radio communication unit that enables cooperative connection to the upstream node unit via an upstream radio link), and the radio base station unit is a relay radio communication of the downstream node unit, which is another radio communication unit on the downstream side. By receiving an attachment from the unit (hereinafter referred to as the downstream relay wireless communication unit), a cooperative connection to the downstream node unit is possible via the downstream linked wireless bearer (hereinafter referred to as the downstream wireless link), and the EPC function is enabled. The unit includes a communication firmware storage unit that stores communication firmware in which the communication protocol stack is incorporated, and a communication control unit that controls wireless network communication by executing the communication firmware, and is a transport layer on the control plane side of the communication protocol stack. As a new protocol layer on the upper layer side of the above, it is broadcast information used for controlling the construction and management of the cooperative wireless bearer between the EPC control unit of the upstream node unit and the EPC control unit of the downstream node unit. A wireless cooperation protocol layer that handles transmission and reception of cooperation notification information is added, and the communication control unit incorporates the cooperation notification information into the cooperation notification packet defined on the wireless cooperation protocol layer, and also between the upstream node unit or It is equipped with a linkage notification information transmission / reception control unit that executes transmission / reception control of cooperation notification information with the downstream node unit as transmission / reception control of cooperation notification packets based on the packet transmission / reception protocol specified on the transport layer. It is a feature.

Further, the wireless network system of the present invention is a wireless communication unit for performing wireless network communication with a mobile terminal in accordance with a communication protocol stack defined by 3GPP (Third Generation Partnership Project), and the mobile terminal is a terminal radio. A wireless base station unit that can be connected via a bearer, an EPC (Evolved Packet Core) functional unit that is wiredly connected to the wireless base station unit and functions as an upper network control unit for the wireless base station unit, and a wired connection to the EPC functional unit. At the same time, by attaching to the radio base station section (upstream radio base station section) of the upstream node unit, which is another wireless communication unit on the upstream side, the upstream node unit and the upstream node unit can be connected via the linked radio bearer (upstream radio link) on the upstream side. It is equipped with a relay wireless communication unit that enables cooperative connection, and the wireless base station unit attaches from the relay wireless communication unit (downstream relay wireless communication unit) of the downstream node unit, which is another wireless communication unit on the downstream side. By receiving, the linked connection with the downstream node unit is possible via the linked wireless bearer (downstream wireless link) on the downstream side, and the EPC function unit stores the communication firmware in which the communication protocol stack is incorporated. It is equipped with a storage unit and a communication control unit that controls wireless network communication by executing communication firmware, and EPC control of the upstream node unit as a new protocol layer on the upper layer side of the transport layer on the control plane side of the communication protocol stack. A wireless cooperation protocol layer that handles transmission and reception of cooperation notification information, which is notification information used for controlling the construction and management of the cooperation wireless bearer, is added between the unit and the EPC control unit of the downstream node unit. The communication control unit incorporates the linkage notification information into the linkage notification packet defined on the wireless linkage protocol layer, and controls the transmission / reception of the linkage notification information between the upstream node unit and the downstream node unit. A group of wireless communication units in which multiple wireless communication units equipped with a cooperative notification information transmission / reception control unit that executes as transmission / reception control of linked notification packets according to the packet transmission / reception protocol specified on the port layer are connected to each other by a linked wireless bearer. A mobile terminal consisting of a mobile terminal connected to a first radio communication unit forming any one of a plurality of radio communication units via a terminal radio bearer, and a second radio forming any one of the other. A mobile terminal connected to a communication unit via a terminal wireless bearer, two or more wireless communication units from the first wireless communication unit to the second wireless communication unit, and a cooperative wireless bearer that connects these wireless communication units to each other. It is characterized in that user data is transmitted and received via and. The upstream wireless link and the downstream wireless link differ only in whether they are constructed on the upstream side or the downstream side of the wireless communication unit of interest, and the relay wireless communication unit of the adjacent wireless communication unit. The functional entity as a cooperative wireless bearer that interconnects the radio base station and the radio base station is the same, and hereinafter, when these are collectively referred to, they are also simply referred to as "wireless link".

The wireless communication unit of the present invention is provided with a relay wireless communication unit that can be connected to the wireless base station unit (upstream wireless base station unit) of the upstream node unit via an upstream wireless link. Further, the radio base station unit can be connected to the relay radio communication unit (downstream relay radio communication unit) of the downstream node unit via the downstream radio link.

That is, the relay wireless communication unit of one wireless communication unit can wirelessly connect to the wireless base station of another wireless communication unit. As a result, a plurality of wireless communication units can be linked and connected via a wireless link, and the wireless communication area for mobile terminals can be expanded. Further, the control plane side of the communication protocol stack has a unique configuration in which a wireless cooperation protocol layer, which is a new protocol layer, is added to the upper layer side of the transport layer. By incorporating the linkage notification information used for controlling the construction and management of the wireless link (linkage wireless bearer) into the linkage notification packet defined on the wireless linkage protocol layer, it is possible to link between multiple wireless communication units to be linked. It is possible to greatly simplify the form of transmission / reception control of the cooperation notification information of the above, and also to simplify the control programming. As a result, it is possible to finely control the linked connection by the wireless link between the wireless communication units.

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 electric 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). A conceptual diagram showing a general IP packet in comparison with the structure of a linked notification packet. The figure which conceptually shows the protocol stack on the control plane side used in this invention. Similarly, a diagram conceptually showing the protocol stack on the user plane side. The figure which conceptually shows the channel mapping of the downlink used in this invention. 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. Conceptual diagram of the channel map. The figure which shows typically the contents of the routing management table of each node unit in the wireless network system of FIG. A communication flow diagram showing the flow of updating the routing management table of each node unit using the linkage notification packet. The communication flow diagram following FIG. 14A. A communication flow diagram showing the flow of updating wireless connection topology information in each node unit using a linked notification packet. 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). A communication flow diagram showing an IP packet transfer control sequence between UEs connected to the same wireless communication unit. A communication flow diagram showing an IP packet transfer control sequence between UEs connected to adjacent wireless communication units. A communication flow diagram showing an IP packet transfer control sequence between UEs connected to both ends of three cascaded wireless communication units. The communication flow diagram which shows the control sequence which forwards an IP packet to an external network through the router of the wireless communication unit located at the end of three wireless communication units connected in cascade. A communication flow diagram (in the case of non-permission) showing the flow of processing for determining permission for constructing a linked wireless bearer using a temporary radio link. A communication flow diagram (in the case of permission) showing the flow of processing for determining permission for constructing a linked wireless bearer using a temporary wireless link. A communication flow showing the flow of processing for rejecting attachments to candidate units using the rejection list (connection non-permitted unit registration unit).

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 each 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 a wireless link 55 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 vessels, 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 mobile body (vehicle or the like) other than a ship, or may be fixedly arranged, for example, at a desired installation destination on land.

FIG. 2 shows a 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 shown separately from each other in the present specification, the same number is given to the corresponding component, and an uppercase 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 of the wireless communication unit 1 (A) side will be mainly used, but the wireless communication unit 1 (B) side will also be described with reference to the corresponding reference numerals as needed. 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 a alternate long and short dash line.

The wireless communication unit 1 (A) is connected to the 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 the wireless base station unit 4 (A). It has an EPC (Evolved Packet Core) function unit 3 (A) that is connected by wire and functions as an upper network control unit for the radio base station unit 4 (A). Further, in the EPC function unit 3 (A), a cooperative 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 node unit) on the upstream side. (Upstream wireless link) The relay wireless communication unit 9 (A) that can be connected via the 55 (A) 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). It includes an EPC function unit 3 (B) and a relay wireless communication unit 9 (B) connected by wire to the EPC function unit 3 (B). In the relay wireless communication unit 9 (B), for example, as shown in FIG. 11, another wireless communication unit (upstream node unit) 1 (C) is arranged on the upstream side of the wireless communication unit 1 (B). Then, it is possible to connect to the wireless base station unit 4 (C) of the wireless communication unit 1 (C) via the wireless link 55 (B) (see FIG. 11). Further, the radio base station unit 4 (B) is linked to the downstream relay radio communication unit 9 (A) (downstream relay radio communication unit) of the downstream radio communication unit 1 (A) (downstream node unit). It is possible to connect via the bearer (downstream wireless link) 55 (A). The wireless link 55 (A) is, for example, an upstream wireless link when viewed from the wireless communication unit 1 (A), and is a downstream wireless link when viewed from the wireless communication unit 1 (B).

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, S-GW (Serving Gateway) 6, which is a gateway on the user plane side, EPC function unit 3, and upstream network elements of the EPC function unit 3 (here, router 8 (described later) and relay wireless communication unit). It has a P-GW (PDN (Packet Data Network) Gateway) 7 that is located at the node of 9) and manages IP addresses toward the upstream network element side (that is, the upstream node unit side). A plurality of UEs 5 are wirelessly connected to the radio base station unit 4 via the terminal radio bearer 57. Further, an application server 8'which is a distribution source of user data composed of video data, image data, or audio data is connected to the router 8.

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.

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) and the bus 306 and the like connecting them to each other. Further, a flash memory 305 is connected to the bus 306, and communication firmware 305a (a function realization program of the communication control unit) including a communication protocol stack for EPC is stored therein.

6 and 7 show the communication protocol stack used by the wireless communication unit 1, FIG. 6 shows the protocol stack on the control plane side, and FIG. 7 shows the co-protocol stack on the user plane side. Each protocol stack is divided into a stack for wired communication and a stack for wireless communication, and in FIGS. 6 and 7, the portion displayed as "LTE" indicates the stack for wireless communication. For convenience of explanation, each figure shows a state in which the wireless communication unit 1 (A) and the wireless communication unit 1 (B) are connected by a wireless link. The protocol stack used by the EPC function unit 3 includes a core network side interface Core and a radio access network side interface RAN. In FIGS. 6 and 7, only the core network side interface Core is shown for the wireless communication unit 1 (A) side for the sake of simplification of the description.

First, the protocol stack on the control plane side of FIG. 6 will be described. The radio base station unit (eNodeB) 4 is connected to the radio access network side interface RAN of the EPC function unit 3. The protocol stack in this section consists of a PHY (physical) layer (L1), a MAC (Medium Access Control) layer (L2) that forms a data link layer, an IP (Internet Protocol) layer that forms a network layer, and UDP (UPP) that forms a transport layer. It consists of a User Datagram Protocol) layer and a GTP (GPRS (General Packet Radio Service) Tunneling Protocol) layer that forms the top layer. This connection section becomes wired communication inside the unit, and IP packets are exchanged by tunneling using GTP. Further, the relay wireless communication unit 9 is connected to the core network side interface Core of the EPC function unit 3, and IP packets are exchanged by LAN communication via the IP layer.

On the other hand, the protocol stack of the radio communication section between the relay radio communication unit 9 and the radio base station unit (eNodeB) 4 includes a PHY layer, a MAC layer, an RLC layer, a PDCP layer, and an RRC 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 using 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.

Next, a cooperative wireless bearer (wireless link) is constructed between the two wireless communication units (upstream node unit) 1 (A) and the wireless communication unit (downstream node unit) 1 (B), and these are linked and connected. The control sequence is executed by transmitting and receiving the cooperation notification information used for controlling the construction and management of the cooperation radio bearer between the upstream node unit and the EPC function unit 3 of the downstream node unit. A wireless cooperation protocol layer WLP that handles the cooperation notification information is added to the protocol stack that forms the core network side interface Core.

The protocol stack forming the core network side interface Core includes a PHY layer (L1), a MAC layer (L2), an IP layer, a UDP layer, and a wireless cooperation protocol layer WLP from the lower layer side. The wireless cooperation protocol layer WLP is defined as a new protocol layer peculiar to the present invention constructed on the UDP layer (transport layer). The above-mentioned cooperation notification information is incorporated in the cooperation notification packet defined on the wireless cooperation protocol layer WLP, and the EPC function unit 3 of the upstream node unit and the downstream node unit controls the transmission / reception of the cooperation notification information in the transport layer ( Here, it is executed as transmission / reception control of the cooperation notification packet based on the packet transmission / reception protocol specified in UDP) (the function of the cooperation notification information transmission / reception control unit is realized). UDP is a simple protocol that eliminates the state for confirming the connection and does not have a function of detecting an error in the transmitted / received data or a difference in the order. For example, in the case of TCP (Transmission Control Protocol), which is a protocol of the same transport layer, start processing and end processing are performed in addition to packet communication of the data body, but UDP does not perform start processing and end processing. Further, TCP returns ACK (acknowledgement) as a response to the reception of a packet, but UDP does not return ACK. The UDP data transmission / reception procedure is simplified in this way, and contributes to speeding up the coordination connection control between units. The function realization program of the wireless cooperation protocol layer WLP is incorporated as the wireless cooperation protocol layer module 305p in the communication firmware 305a in FIG.

Next, the protocol stack on the user plane side of FIG. 7 will be described. Since the structure of the protocol stack is common to the stack structure on the control plane side of FIG. 6 in many respects, the differences will be mainly described below, and the structurally overlapping protocol layers will be described in FIG. The same code as is given and the details are omitted. The core network side interface Core of the EPC function unit 3 concentrates on the passive transfer processing of the received IP packet for the user data, so that the uppermost layer is the IP layer which is the network layer. Further, in the UE 5 or the application server (APP) 8'which is the source and destination of the user data, the uppermost protocol layer that handles the transmission and reception of the user data is the application layer APP.

The upper part of FIG. 5 is a schematic diagram of an IP packet used for transferring user data. 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. On the other hand, the lower part of the figure is a schematic diagram of the cooperation notification packet 1350, which consists of an IP header 1351 and a payload 1352. The difference from the IP packet used for forwarding user data is that the destination address is issued as an IP packet fixed to a specific address (“172.17.1.1” in the lower part of FIG. 5). This fixed destination address also serves as identification information indicating that the IP packet is a linked broadcast packet. By using such a linked notification packet 1350, the linked broadcast information incorporated in the payload 1352 of one linked broadcast packet can be easily shared among a plurality of wireless communication units linked and connected by a wireless link. Can be done.

Next, the wireless cooperation protocol layer module 305p of the communication firmware 305a includes the following three control modules.
-Routing management module 305pr
It manages in which direction the IP packet (user data and control data) received by the radio base station unit 4 or the relay radio communication unit 9 is transmitted from the viewpoint of the EPC function unit 3. Basically, one of the following three is executed.
(Management control 1) Forward the IP packet to the upstream side. That is, the direction is toward the radio base station unit 4 of the upstream node unit via the relay radio communication unit 9 of the own node unit and the upstream radio link.
(Management control 2) Forward the IP packet to the downstream side. That is, the direction is toward the relay radio communication unit 9 of the downstream node unit via the radio base station unit 4 of the own node unit and the downstream radio link.
(Management control 3) Transfer the IP packet to the application server 8'or UE 5 connected to the local node unit.

The list of node addresses of the upstream node unit and the application server 8'and UE5 connected to the downstream node unit is described among all the node units (wireless communication unit 1) constituting the wireless network system according to the method described in detail later. Information is shared and stored as a routing management table 305f (routing management information). The contents of the routing management table 305f are periodically updated by communication via the cooperation notification packet between adjacent node units. The operation of the routing management module 305pr is whether the destination address of the received IP packet exists on the upstream side (management control 1) or on the downstream side by referring to the routing management table 305f (management control 2). ), It is concentrated in the process of simply determining whether it is in the area of the own node unit (management control 3).

-Topology management module 305pt
It manages the wireless connection topology (topological connection form via wireless link) of all the node units that make up the wireless network system. The wireless connection topology can be grasped by sharing the specific information of the upstream node unit and the downstream node unit seen from the own node unit among all the node units (wireless communication unit 1), and the content thereof is the topology. It is stored as a management table 305tt (topology management information). The contents of the topology management table 305tt are also periodically updated by communication via a linkage notification packet between adjacent node units. In addition, the rejection list 305rr, which will be described later, is also incorporated in the topology management module 305pt.

・ Wireless link management module 305pj
It manages the state of the wireless link (cooperative wireless bearer) constructed by the relay wireless communication unit 9 or the wireless base station unit 4. Specifically, when the relay radio communication unit 9 of the own node unit connects to the radio base station unit 4 of the upstream node unit via the radio link 55, or the relay radio communication unit 9 of the downstream node unit connects to the radio base station unit 4 of the own node unit. When connected to the local part 4 via the wireless link 55, the cooperation mode is set, and the above-mentioned routing management module 305pr and topology management module 305pt are activated. On the other hand, when there is no connection of another node unit via the wireless link 55, the isolated mode is set and the contents of the routing management information and the topology management information are cleared. Further, a channel map 305g for determining a channel to be assigned to the wireless link 55 in the cooperation mode is also incorporated in the wireless link management module 305pj.

FIG. 11 shows an example of a configuration 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 (C) are bases of a pair of wireless communication units (1 (A) and 1 (B), 1 (B) and 1 (C)) adjacent to each other. Radio links 55 (A) and 55 in a positional relationship in which station cells (for example, in the case of wireless communication units pair 1 (A) and 1 (B), 50 (A) and 50 (B) in FIG. 1) partially overlap. It is connected by (B). For example, the UE 5 (A) (mobile terminal) connected to one of the wireless communication units 1 (A) and 1 (B) and the UE 5 (B) (mobile terminal) connected to the other are a wireless communication unit pair. IP packets can be transmitted and received via the linked wireless bearer 55 (A) connecting 1 (A) and 1 (B) and the wireless communication units to 1 (A) and 1 (B). All of the wireless communication units 1 (A) to 1 (C) may be mounted on a mobile body such as the above-mentioned ship, or only a part of the wireless communication units 1 (A) to 1 (C) may be mounted on the mobile body, and the remainder may be mounted. Things may be fixedly installed in a building or the like. Further, in the area where the wireless communication network is not deployed, all the wireless communication unit groups 1 (A) to 1 (C) may be fixedly arranged.

Further, in FIG. 11, the number of wireless communication units connected by the wireless links 55 (A) and 55 (B) is 3 (or more). For example, the UE (mobile terminal) 5 (A) connected to the wireless communication unit 1 (A) has the UE (mobile terminal) 5 (C) connected to the wireless communication unit 1 (C) and the wireless communication unit 1. IP packets can now be sent and received via the linked wireless bearers 55 (A) and 55 (B) that connect (A) to 1 (C) and the wireless communication units 1 (A) to 1 (C). ing. In this way, the number of connected wireless communication units can be easily increased, and IP packets can be transmitted / received by wireless communication between UEs 5 in a wider area.

In the table below FIG. 11, for the wireless communication unit groups 1 (A) to 1 (C), the communication frequency / channel number of the wireless links 55 (A) and 55 (B), the tracking area code, and the connected Node addresses of UEs 5 (A) to 5 (C) and application servers 8'(A) to 8'(C) (For simplification of display, a sub-network that collects the node addresses of a plurality of UEs 5 and application servers 8'. The destination address of the cooperation notification packet transmitted / received on the wireless cooperation protocol layer WLP is shown collectively. The destination address of the linked notification packet is the same for all the wireless communication units 1 (A) to 1 (C). Further, when viewed as a whole wireless network system, the node addresses of all the UEs 5 (A) to 5 (C) and the application servers 8'(A) to 8'(C) that are connected are the wireless communication unit group 1 ( It is shared between A) and 1 (C) and stored in the routing management table 305f of FIG. Further, the connection topology information ([A] → [B] → [C]) of the wireless communication units 1 (A) to 1 (C) is also shared in the same manner and stored in the topology management table 305tt. The specific information ([A], [B], [C] above) of each wireless communication unit 1 (A) to 1 (C) stored in the topology management table 305tt is the wireless communication unit 1 (A). The ID may be uniquely assigned to 1 (C), or the node addresses of the wireless communication units 1 (A) to 1 (C) (for example, EPC function unit 3, radio base station unit 4, relay wireless communication). Any node address of Part 9 or a unit node address assigned separately from these may be used. In this embodiment, the node address of the EPC function unit 3 is used.

FIG. 13 shows an example of the contents of the routing management table 305f, and the routing management tables of the wireless communication units 1 (A), 1 (B), and 1 (C) in the connected state of FIG. 11 are shown in order from the top. 305f is shown respectively. The node addresses of the UEs 5 (A) to 5 (C) and the application servers 8'(A) to 8'(C) are the node existing on the downstream route side and the node existing on the upstream route side when viewed from the own node unit. Are memorized in a form that distinguishes them from each other.

Further, in the flash memory 305, the MME entity 305b, S-GW entity 305c, and P- that virtually realize the functions of MME2, S-GW6, and P-GW7 in FIG. 2 using the above communication protocol stack as a platform. Each program of GW entity 305d is installed. 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 on the upstream communication interface 304A, and the input / output port of the IP packet for S-GW is secured on the downstream communication interface 304B. In the above configuration, the MME2, S-GW6, and P-GW7 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 bus 406 connecting them to each other, and the like. 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, the bus 406 is connected to a wireless communication unit 412 for wirelessly connecting to the UE by constructing a terminal wireless bearer, and a communication interface 404. 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 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 communication firmware 905a including an LTE protocol stack for a relay radio communication unit is stored therein. Further, the bus 906 is connected to a wireless communication unit 912 for wirelessly connecting to the upstream wireless base station unit by constructing a wireless link, and a communication interface 904. The communication interface 904 is connected to the upstream communication interface 304A of the EPC function unit 3 by a wired communication bus 30. 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 procedure for connecting the relay radio communication unit 9 to the upstream radio base station unit is formally the same as the procedure for connecting the UE (mobile terminal).

Further, the communication bus 30 is connected to a router 8 that relays transmission / reception of IP packets between the EPC function unit 3 and the application server 8'(or may be an external network such as the Internet). ..

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 location (for example, at sea) where the external power supply voltage cannot be used such as commercial alternating current. be. The portable housing 23 is a box type made of metal or reinforced resin, and in the example shown in FIG. 3, the caster 24C is 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.

If the output voltage of the secondary battery module 21 drops due to discharge, remove the secondary battery module 21 from the portable housing 23 and attach it 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 alternating current or the centralized power supply unit provided in the mobile body, and can be converted and output to 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 equipped with a microcomputer 100 as a processing subject. The microcomputer 100 includes a CPU 101, a RAM 102 that serves as a program execution area, a ROM 103, 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.

Further, the monitor 109 is connected to the input / output unit 104 via the graphic controller 1091. A touch panel 110 forming an input unit is superimposed on the monitor 109, and various information input necessary for operation control of the UE 5 is input in cooperation with various software operation units (buttons, icons, etc.) displayed and formed on the monitor 109. It is supposed to be done. 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. 3 via the terminal wireless bearer 57.

Next, FIG. 8 shows the 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 the 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 radio 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: Discontinuous Transmission) are supported transport channels.
-RACH (Random Access Channel): A transport channel to 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, and uplink data transmission request ( Scheduling Request: SR) is a physical channel used to notify the radio base station unit 4.
-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 the 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.

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 of the orthogonal frequency axis and the time axis are divided and allocated to the UE 5, and the subcarriers 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 (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.

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, and 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 constructs the radio link 55 and the terminal radio bearer 57 of FIG. 2 by selecting a predetermined frequency channel. Will be done. That is, the channel between the downstream node units, the channel between the upstream node units, 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 embodiment of FIG. 11, the EPC function unit 3 fixedly sets the set frequency channel of the (downstream) radio link 55 to the (downstream) unit-to-unit channel, which is one 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) unit-to-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.

Further, in FIG. 11, the cell of the wireless communication unit 1 (A), the cell of the wireless communication unit 1 (B), and the cell of the wireless communication unit 1 (C) are overlapped with each other. In this case, for example, the inter-unit channel of the wireless links 55 (A) and (B) connecting the upstream and downstream wireless communication units 1 (A) and 1 (C) when viewed from the wireless communication unit 1 (B) is the same. By setting the above to different frequency channels, it is possible to effectively prevent radio wave interference between a plurality of cells partially overlapping each other, which are involved in the construction of the wireless links 55 (A) and (B). Can be done.

More specifically, each EPC function unit 3 of the wireless communication units 1 (A) to 1 (C) sets a channel between downstream node units to the upstream wireless link when the (upstream) wireless link is constructed. On the other hand, the terminal channel group is set as a frequency channel group different from that of the downstream node unit channel and the upstream node unit channel. For example, when focusing on the wireless communication unit 1 (B), the EPC function unit 3 of the wireless communication unit 1 (B) sets, for example, the channel between upstream node units set for the upstream wireless link 55 (B). Set to CH2. On the other hand, the EPC function unit 3 of the wireless communication unit 1 (A) is an upstream wireless link 55 (A) seen from the wireless communication unit 1 (A) (a downstream wireless link when viewed from the wireless communication unit 1 (B). ) Is set to CH1 which is different from CH2. The channel between upstream node units (which is a channel between downstream node units when viewed from the wireless communication unit 1 (B)) is set to CH1. At this time, by setting the channel CH1 between the downstream node units and the channel CH2 between the upstream node units as different frequency channels in the same band, the radio base station unit 4 and the relay radio communication unit 9 for constructing a wireless link There is an advantage that the hardware can be easily configured with a single band specification.

Further, the terminal-side channel is set to the same channel as the channel between downstream node units 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 set to the same channel as the channel between downstream node units among the frequency channels belonging to the same band. The hardware of the radio base station unit 4 and the relay radio communication unit 9 can be made into a single band specification including the construction of the terminal wireless bearer, which contributes to the simplification of the device configuration. The terminal-side channel may be selectably selected from the remaining frequency channels other than those set as the channel between the downstream node units and the channel between the upstream node units.

Further, in the present embodiment, the band 28 specified in 3GPP is adopted as the same band as described above. The band 28 is set to the VHF band (700 MHz band), which has a vacancy due to the stoppage of terrestrial analog television broadcasting. Since band 28 is a low frequency band, its communication speed is somewhat slow, so its adoption in areas with many terminal subscribers such as urban areas is not being actively promoted, and the usage 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 distant reachability of radio waves, and it is possible to expand the cell coverage of one wireless communication unit. In addition, it has the property of being easily connected even if there are underground or obstacles, and can be said to be suitable for constructing the wireless network system of the present invention, for example, at sea or in a mine.

Next, in the wireless network system of the present invention, as a specific method for making the channel settings between adjacent wireless links 55 (A) and 55 (B) different from each other as shown in FIG. 11, for example, the wireless link 55 This can be performed by each wireless communication unit 1 (A) to 1 (C) sharing channel information between units by transmitting and receiving the above-mentioned cooperation notification packet via (A) and 55 (B).

When the upper limit of the number of wireless communication units participating in the wireless network system is set, for example, in FIG. 11, the combination of node addresses assigned to the individual wireless communication units 1 (A) to 1 (C) is used. Therefore, the types of inter-unit channels to be allocated are uniformly determined in the form of a channel map, and this channel map is incorporated into the EPC function unit 3 of each wireless communication unit in order to further simplify the process. It is valid. By referring to the channel map, each EPC function unit 3 can be set so that the inter-unit channels of adjacent wireless links are different. In this case, the EPC function unit 1 is a channel map storage unit that stores a channel map showing the correspondence between the frequency channel group that can be selected as the channel between the downstream node units and the node address of the downstream relay radio communication unit that is the connection destination. In response to the attachment request from the downstream relay radio communication unit, the node address of the downstream relay radio communication unit is acquired, and the frequency channel corresponding to the acquired node address is specified on the channel map. It operates to set the identified frequency channel as a channel between downstream node units.

FIG. 12 shows an example of a channel map of 305 g. In the channel map 305g, the number of wireless communication units 1 participating in the system construction is four, and unit specific information MID01 to MID04 are assigned to each. Then, according to the combination of the unit specific information, the channel numbers of the inter-unit channels set between the corresponding wireless communication units are defined so as not to be duplicated. The unit specific information may be the authentication information IMSI (International Mobile Subscriber Identity) of the wireless communication unit 1 or may be a node address.

Hereinafter, the flow of the attach sequence of the relay wireless communication unit 9 and the UE 5 will be described with reference to FIGS. 16 and 17. FIG. 16 shows an attach 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. At this time, the relay wireless communication unit 9 transmits the IMSI for authentication. 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 on the TS3. If the bearer is set, the S-GW 6 sends a bearer setting response to the MME2 on the TS4.

The MME 2 searches the TS5 for the wireless communication channel corresponding to the requesting unit on the channel map 305 g (FIG. 12). Then, the TS6 notifies the radio base station unit 4 of the radio bearer setting request (attachment acceptance) together with the set channel number. In response to this, the radio base station unit 4 transmits a MIB (Master Information Block) including a setting channel number of the radio bearer (radio link) 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 (touch acceptance) in the TS9. In TS10, the relay radio communication unit 9 sets a radio link 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. 17 shows the attachment sequence of the 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 IMSI 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 on the 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 terminal radio bearer group 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. In response to this, the radio base station unit 4 transmits a MIB (Master Information Block) including a setting channel number of the radio bearer (radio link) to be set by the TS 17 to the UE 5.

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. In TS20, the UE 5 sets the terminal-side wireless bearer and returns the session start response to the wireless 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 radio communication unit 9 are basically executed according to the same procedure except for the contents of the frequency channel setting.

In the LTE system, in order to flexibly change the transmission amount of the broadcast information such as the above set channel number for each operation / environment, it can be used variably using a fixed broadcast information resource using PBCH and PDSCH. Used in combination with wireless resources. Here, PBCH, which is a fixed resource, is used because the broadcast information is defined as the information first acquired by the UE 5 (relay radio communication unit 9), and the UE 5 (relay radio communication unit 9) uses the radio base station unit (relay radio communication unit 9). This is because it is necessary to be able to receive the notification from eNodeB) 4. The UE 5 first receives the PBCH, which is a fixed resource, obtains the minimum information for receiving the PDSCH from the PBCH, and reads the broadcast information sent by the PDSCH based on the minimum information. Since the PDSCH is a variable resource that can be allocated in RB units, the amount of broadcast information transmitted by the PDSCH is variable. As a result, the amount of resources used for broadcast information can be changed, and wireless resources can be allocated according to the amount of broadcast information that differs depending on the network operation and environment.

Of the broadcast information transmitted by this PBCH, the above MIB is transmitted at the beginning of the radio frame (that is, the subframe number = 0), and the time resource and the frequency resource are always fixed. Assigned. The transmission information is usually, for example, information for receiving other broadcast information (for example, SIB (System Information Block)) by PDSCH, radio frame number (SFN: System Frame Number), and the like. However, in the present embodiment, using this MIB, the radio base station unit 4 distributes the channel information of the terminal radio bearer or the radio link to the UE 5 (relay radio communication unit 9). Although the size of the MIB is fixed to 24 bits, 10 bits of the spare area are reserved areas, so that it is possible to incorporate the setting channel information of the wireless bearer, for example, by using this spare area.

FIG. 18 shows a flow of transmission processing of IP packets between UEs 5 (UE (I) and UE (II)) connected to the same wireless communication unit 1. U1 and U2 are attachment sequences described with reference to FIG. 15, and a terminal radio bearer is constructed. At U3, an IP packet is sent from the UE (I) to the radio base station unit 4 as an uplink packet. The radio base station unit 4 transfers this to the EPC function unit 3. The EPC function unit 3 confirms whether or not the IP address of any UE connected to the local node unit 1 (A) matches the destination address recorded in the header of the received IP packet. .. In the case of FIG. 18, the IP address of the UE (II) corresponds to this, and the IP packet is transferred back to the subordinate radio base station unit 4 as a downlink packet at D1. The radio base station unit 4 receives this and transfers it to the UE (II), and the process is completed.

FIG. 19 shows an IP packet transmission process between the UE 5 (A) connected to the wireless communication unit 1 (A) and the UE 5 (B) connected to the adjacent wireless communication unit 1 (A) in FIG. It shows the flow of. The processing from U1 to U3 is the same as in FIG. In U3, the EPC function unit 3 of the wireless communication unit 1 (A) refers to the routing management table 305f of FIG. 13, and the destination address of the received IP packet is any of the ones connected to the local node unit 1 (A). It is confirmed that the IP address of the UE does not match, and whether the destination address exists in the upstream route or the downstream route. For example, when the destination address exists on the upstream route side, the IP packet is transferred to the wireless communication unit 1 (B) on the upstream side by the wireless link 55 (A) at U4. The wireless communication unit 1 (B) receives this IP packet, and the IP address of any UE connected to the local node unit 1 (B) is recorded in the header of the received IP packet as the destination. Check if it matches the address. If they match, the IP packet is forwarded as a downlink packet to the subordinate radio base station unit 4 at D2. The radio base station unit 4 receives this and transfers it to the UE 5 (B), and the process is completed.

For example, the UE that is the source of the IP packet is connected to the middle of the cascaded wireless communication units, and the UE that is the destination is connected to the wireless communication unit that is downstream from the wireless communication unit. In the case of a UE, the EPC function unit 3 refers to the routing management table 305f in the above U3 and confirms that the destination address of the received IP packet matches the IP address of the UE on the downstream route side. It will be. The IP packet is transferred to the radio base station unit 4 as a downlink packet, and further transferred to the radio communication unit to which the UE to be the transmission is connected by using the linked radio bearer on the downstream side.

FIG. 20 shows an IP packet between the UE 5 (A) connected to the wireless communication unit 1 (A) and the UE 5 (C) connected to the wireless communication unit 1 (C) two destinations ahead in FIG. It shows the flow of transmission processing. The processing from U1 to U4 is the same as in FIG. In U4, the EPC function unit 3 of the wireless communication unit 1 (B) refers to the routing management table 305f, and it is confirmed that the destination address recorded in the header of the received IP packet exists, for example, on the upstream route side. If so, the IP packet is transferred to the wireless communication unit 1 (C) on the upstream side by the wireless link 55 (B) at the U5. The wireless communication unit 1 (C) receives this IP packet and confirms that the IP address of the UE 5 (C) connected to the own node unit matches the IP address of the destination. Then, at D3, the IP packet is forwarded as a downlink packet to the subordinate radio base station unit 4. The radio base station unit 4 receives this and transfers it to the UE 5 (C), and the process is completed.

FIG. 21 shows a process when the IP packet from the UE 5 (A) connected to the wireless communication unit 1 (A) has a destination address outside the wireless network system. The processing from U1 to U5 is the same as that in FIG. In U5, the EPC function unit 3 of the wireless communication unit 1 (C) refers to the routing management table 305f, confirms that the destination address recorded in the header of the received IP packet exists in the upstream route, and determines that the destination address exists in the upstream route. And forward the IP packet to the router 8.

The communication firmware 305a having the above configuration functions as a program for realizing the following functional parts related to the creation and updating of the routing management table 305f (see FIG. 11).
-Routing management information reception control command unit: A mobile terminal (UE) connected to the radio base station section of the other node unit, with the wireless communication unit connected to the upstream side or downstream side of the own node unit as another node unit. It instructs the cooperation notification information transmission / reception control unit to receive the routing management information including the node address of 5 from the upstream node unit or the downstream node unit as the cooperation notification information.
-Routing management information integrated processing unit: Routing management of another node unit that receives routing management information including the node address of the mobile terminal 5 connected to the radio base station unit 4 of the own node unit from the upstream node unit or the downstream node unit. Integrate with information.
-Routing management information storage control unit: The integrated routing management information is stored in the routing management information storage unit (in FIG. 3, the storage area of the routing management table 305f of the flash memory 305 corresponds to this).
-Routing management information transmission control command unit: Instructs the linkage notification information transmission / reception control unit to transmit the integrated routing management information to the downstream node unit or the upstream node unit as cooperation notification information.
-User data transfer control unit: By referring to the routing management information stored in the routing management information storage unit, the node address of the mobile terminal 5 to which the user data is transferred is specified, and on the user plane side of the communication protocol stack. Controls the transfer of user data.

With the above configuration, it is possible to smoothly and easily execute the routing management information sharing process among a plurality of wireless communication units 1 linked and connected by the transmission / reception processing of the linkage notification packet on the wireless linkage protocol layer WLP. can. Hereinafter, an example of the specific processing flow will be described with reference to FIGS. 14A and 14B. Here, the case where the wireless communication units 1 (A) to 1 (C) are in the connected state shown in FIG. 11 is taken as an example.

The update process of the routing management table 305f is performed by a so-called bucket relay method via a linked notification packet, that is, the wireless communication unit 1 (A) located at the downstream end of the wireless network system and the wireless communication unit 1 (A) located at the upstream end. It is carried out reciprocally with C). That is, the wireless communication unit 1 (A) at the downstream end, which is the processing starting point, issues a linkage notification packet for notifying the node address of the UE 5 (and the application server 8') connected to the own node unit as an update trigger packet to the upstream node. Send to the unit. Upon receiving this, the upstream node unit updates the contents of the downstream route side of the routing management table 305f by referring to the contents of the linkage notification packet, and updates the contents of the downstream route side to the next upstream node unit by the linkage notification packet. Communicate (Fig. 14A). Then, when the flow of this transmission reaches the wireless communication unit 1 (C) at the upstream end, the wireless communication unit 1 (C) at the upstream end updates the contents on the downstream route side of the routing management table 305f, and then itself. A linkage notification packet that notifies the node address of the UE 5 (and application server 8') connected to the node unit is issued and transmitted to the downstream node unit. Upon receiving this, the downstream node unit updates the contents of the upstream route side of the routing management table 305f by referring to the contents of the linkage notification packet, and updates the contents of the upstream route side to the next downstream node unit by the linkage notification packet. Communicate (Fig. 14B). Then, when this transmission flow returns to the wireless communication unit 1 (A) at the downstream end, the wireless communication unit 1 (A) updates the contents on the upstream route side of the routing management table 305f, and a series of processes is completed. do. This sequence is repeated by the wireless communication unit 1 (A) at the downstream end periodically issuing the above-mentioned update trigger packet (for example, at predetermined time intervals), and the routing management table 305f is updated. Can be maintained at.

Hereinafter, a more detailed description will be given. First, the EPC function unit 3 of the wireless communication unit 1 (A) at the downstream end has the node address (192.168.1.0/24) of the UE 5 connected to the own node unit and the node address (172.16.1.0/) of the application server 8'. 24) and is issued as a linked notification packet embedded in the payload. Then, the relay radio communication unit (BTC) 9 is made to transmit the cooperation notification packet via the upstream radio link 55 (A) (U101). The wireless communication unit 1 (B) receives this at the wireless base station unit 4, and updates the contents on the downstream route side of the routing management table 305f by the above node address written in the cooperation notification packet (U102).

At this time, the fact that the source of the cooperation notification packet is the node unit on the downstream side when viewed from the wireless communication unit 1 (B) can be clearly specified from any of the following logics in the case of the present embodiment.
(1) The cooperation notification packet is received by the radio base station unit 4.
(2) The source address written in the linkage notification packet indicates the node address of the downstream node unit. The issuer of the linkage notification packet is the EPC function unit 3, and whether the source address belongs to the downstream node unit or the downstream node unit can be grasped by referring to the topology management table 305tt.

Subsequently, the EPC function unit 3 of the wireless communication unit 1 (B) receives the node address (192.168.1.0/24) of the UE 5 and the node address (172.16.1.0) of the application server 8'received from the wireless communication unit 1 (A). / 24) integrates the node address (192.168.2.0/24) of the UE 5 connected to the local node unit and the node address (172.16.2.0/24) of the application server 8', and incorporates these into the payload for linked notification. Issue a packet. Then, the relay radio communication unit (BTC) 9 is made to transmit the cooperation notification packet via the upstream radio link 55 (B) (U103).

The EPC function unit 3 of the wireless communication unit 1 (C) at the upstream end receives the cooperation notification packet at the wireless base station unit 4, and the node address written in the cooperation notification packet causes the downstream route side of the routing management table 305f. Update the contents of (U104). On the other hand, since the upstream node unit is not connected to the wireless communication unit 1 (C), the content on the upstream route side of the routing management table 305f is blank (see the bottom of FIG. 13). By the sequence up to this point, the content update on the downstream route side of the routing management table 305f of each wireless communication unit 1 (A) to 1 (C) is completed.

Subsequently, proceeding to FIG. 14B, the wireless communication unit 1 (C) at the upstream end has the node address (192.168.3.0/24) of the UE 5 connected to the own node unit and the node address (172.16.3.0) of the application server 8'. / 24) and is issued in the linkage notification packet incorporated in the payload. Then, the radio base station unit 4 is made to transmit the cooperation notification packet via the downstream radio link 55 (B) (U105). The wireless communication unit 1 (B) receives this in the relay wireless communication unit 9, and updates the contents on the upstream route side of the routing management table 305f by the above node address written in the cooperation notification packet (U106). At this point, the contents of the routing management table 305f of the wireless communication unit 1 (B) are in the state shown in the center of FIG.

At this time, the fact that the source of the cooperation notification packet is the node unit on the upstream side when viewed from the wireless communication unit 1 (B) can be clearly specified from any of the following logics in the case of the present embodiment.
(3) The cooperation notification packet is received by the relay radio communication unit 9.
(4) The source address written in the linkage notification packet indicates the node address of the upstream node unit in the topology management table 305tt.

Subsequently, the EPC function unit 3 of the wireless communication unit 1 (B) receives the node address (192.168.3.0/24) of the UE 5 and the node address (172.16.3.0) of the application server 8'received from the wireless communication unit 1 (C). / 24) integrates the node address (192.168.2.0/24) of the UE 5 connected to the local node unit and the node address (172.16.2.0/24) of the application server 8', and incorporates these into the payload for linked notification. Issue a packet. Then, the radio base station unit 4 is made to transmit the cooperation notification packet via the downstream radio link 55 (A) (U107).

The EPC function unit 3 of the wireless communication unit 1 (A) at the downstream end receives the cooperation notification packet at the relay wireless communication unit 9, and the node address written in the relay communication unit 1 causes the upstream route side of the routing management table 305f. Update the contents of (U104). On the other hand, since the downstream node unit is not connected to the wireless communication unit 1 (A), the content on the downstream route side of the routing management table 305f is blank (see the upper part of FIG. 13). By the above sequence, the content update process of the routing management table 305f of each wireless communication unit 1 (A) to 1 (C) is completed.

When the connection state of the UE 5 of each wireless communication unit 1 (A) to 1 (C) changes, it is reflected in the routing management table 305f at the next update process. At this time, the contents of the routing management table 305f are replaced (that is, updated) with new contents by erasing the old contents.

The node address of the UE 5 (and the application server 8') connected to the local node unit is individually acquired by the cooperation notification packet issued by each wireless communication unit 1 (A) to 1 (C) and is obtained in the routing management table. It is also possible to update 305f. In this case, the topology management table 305tt distinguishes between upstream and downstream of the source of the cooperation notification packet, and the upstream route side and the downstream route side of the routing management table 305f are updated every time the cooperation notification packet is received. Here, when a UE 5 whose connection is cut off occurs, a separate procedure for deleting the node address of the UE 5 from the routing management table 305f is required. Specifically, the node address of the UE 5 whose connection is cut off is notified by the cooperation notification packet, or the node address of the connected UE 5 (and the application server 8') is notified on the routing management table 305f by the node of the wireless communication unit. It is necessary to either manage it in association with the address. However, if the above-mentioned method is used in which the node addresses of the UE 5 (and the application server 8') connected to each node unit are integrated by the intermediate wireless communication unit 1 (B) and notified by the linked notification packet, the routing management is performed. All that is required is to erase the existing contents of the table 305f, and the processing can be greatly simplified.

Next, the communication firmware 305a also functions as a realization program of the following functional parts related to the creation and update of the topology management table 305tt (see FIG. 11).
-Wireless connection topology information reception control command unit: Regarding the wireless communication unit groups 1 (A) to 1 (C) connected to the upstream side or the downstream side of the own node unit, the wireless communication unit groups 1 (A) to 1 (C) Instructs the linkage notification information transmission / reception control unit to receive the wireless connection topology information that specifies the individual wireless communication units together with the connection order from the upstream node unit or the downstream node unit as cooperation notification information. ..
-Wireless connection topology information update processing unit: Updates the contents of the wireless connection topology information received from the upstream node unit or the downstream node unit by incorporating the own node unit into the wireless communication unit group specified by the wireless connection topology information. do.
-Wireless connection topology information storage control unit: The updated wireless connection topology information is stored in the wireless connection topology information storage unit (in FIG. 3, the storage area of the topology management table 305tt of the flash memory 305 corresponds to this).
-Wireless connection topology information transmission command unit: Instructs the cooperation notification information transmission / reception control unit to transmit the updated wireless connection topology information to the downstream node unit or the upstream node unit.
In this case, the user data transfer control unit controls the transfer of user data based on the wireless connection topology information stored in the wireless connection topology information storage unit.

With the above configuration, it is possible to smoothly and easily execute the processing of sharing the topology management information among a plurality of wireless communication units 1 linked and connected by the transmission / reception processing of the linkage notification packet on the wireless linkage protocol layer WLP. can. Hereinafter, an example of the specific processing flow will be described with reference to FIG. Here, too, the case where the wireless communication units 1 (A) to 1 (C) are in the connected state shown in FIG. 11 is taken as an example. The basic processing flow is as follows: Wireless communication unit 1 (A) located at the downstream end of the wireless network system and wireless communication located at the upstream end by a bucket relay-like method similar to the update processing of the routing management table 305f. It is carried out reciprocally with the unit 1 (C). That is, the downstream end wireless communication unit 1 (A), which is the processing starting point, arranges the node address [A] of the own node unit and the node address [B] of the upstream node unit, for example, from the downstream side to the upstream side. A linkage notification packet incorporated as wireless connection topology information ([A] → [B]) reflecting the order (connection order) is issued as an update trigger packet and transmitted to the upstream node unit (U201).

The wireless communication unit 1 (B), which is an upstream node unit, updates the contents of the topology management table 305tt with the wireless connection topology information ([A] → [B]) of the received cooperation notification packet (U202). Subsequently, the upstream node unit 1 (B) is updated by adding the node address ([C]) of the next upstream node unit to the upstream side of the received wireless connection topology information ([A] → [B]). , The updated wireless connection topology information ([A] → [B] → “C]) is transmitted to the wireless communication unit 1 (C), which is an upstream node unit, using a linked notification packet (U203).

When the transmission flow of the linkage notification packet reaches the wireless communication unit 1 (C) at the upstream end, the wireless communication unit 1 (C) at the upstream end updates the contents of the topology management table 305tt with the received wireless connection topology information. (U204), this is recognized by the own node unit and used as the latest wireless connection topology information ([A] → [B] → “C]), which is used as the downstream node unit by the linked notification packet ([A] → [B] → “C]). (U205). Upon receiving this, the wireless communication unit 1 (B), which is a downstream node unit, updates the topology management table 305tt according to the contents of the wireless connection topology information of the received cooperation notification packet (U206). , The content of the updated wireless connection topology information is transmitted to the next downstream node unit, the wireless communication unit 1 (A), by a linked notification packet (U207). The downstream end wireless communication unit 1 (A) has received the packet. The contents of the topology management table 305tt are updated by the wireless connection topology information, and a series of processing is completed. In this sequence, the wireless communication unit 1 (A) at the downstream end periodically (for example, in advance) sends the above update trigger packet. It can be repeated by issuing (at fixed time intervals) to keep the topology management table 305tt up to date.

The communication firmware 305a determines whether or not attachment can be accepted when the own node unit is a node unit at the downstream end and an attach request is received from a new wireless communication unit (candidate unit) further downstream. It also functions as a realization program for the following functional parts related to control.
-Temporary wireless link construction control unit: The candidate by receiving an attach request from the candidate unit prior to the main construction of the downstream wireless link with the candidate unit, which is a wireless communication unit that is a candidate for the downstream node unit. Build a temporary wireless link with the unit.
-Judgment reference information reception control command: Linked notification information transmission / reception control to receive from the candidate unit via the temporary radio link using the judgment reference information referred to in the final construction permission judgment of the downstream radio link for the candidate unit as the linked notification information. Give instructions to the department.
-Downstream wireless link main construction permission determination unit: Based on the received determination reference information, the downstream wireless link main construction permission determination for the candidate unit is performed.
-Downstream radio link construction control unit: If the result of this construction permission judgment is positive, the temporary radio link is moved to the main construction state as a downstream radio link, but the result of this construction permission judgment is negative. In that case, a detach sequence that cancels the construction state of the temporary wireless link is executed.

According to the above configuration, by temporarily constructing a temporary wireless link with a candidate unit for which a wireless link has not been constructed, the determination reference information is accurately and easily acquired from the candidate unit in the form of being incorporated in the cooperation notification packet. By referring to this, it is possible to smoothly and accurately determine whether or not to connect with the candidate unit (determination of permission to construct the downstream wireless link). If the judgment result is positive, the temporary radio link can be smoothly transitioned to the main construction state of the downstream radio link, while if the judgment result is negative, the temporary radio link construction state can be taken over. A detachment sequence is executed to eliminate the problem, and it is possible to effectively prevent the cooperative connection with the ineligible candidate unit.

The determination reference information is a radio that specifies each wireless communication unit included in the wireless communication unit group together with the connection order for the wireless communication unit group including the candidate units connected to the downstream side or the upstream side of the own node unit. It can include connection topology information. In this case, the downstream wireless link main construction permission determination unit sets the downstream wireless link to the candidate unit when the connection form of the wireless communication unit group indicated by the wireless connection topology information corresponds to a predetermined prohibited connection form. Can be configured to be determined as disallowed. By referring to the wireless connection topology information, it is possible to effectively prevent the cooperative connection with the candidate unit that tries to connect to the node unit at the downstream end by the unsuitable topology.

In this case, the prohibited connection form can be defined as, for example, a connection form in which the same wireless communication unit as any of the other node units connected to the upstream side of the own node unit is a candidate unit. If such cooperative connection of candidate units is not prohibited, the connection topology of wireless communication units via wireless links will be endless (that is, form a loop) among at least some wireless communication unit groups. It will be. For wireless communication units belonging to the endless section, it becomes difficult to distinguish between the wireless communication unit group on the upstream route side and the wireless communication unit group on the downstream route side as seen from the own node unit, and the routing management algorithm becomes complicated. There is a problem to do. Further, all the radio base station portions 4 of the wireless communication units belonging to the endless section are in a state where a part of the transmission / reception bandwidth is always occupied by the construction of the wireless link with the other node unit. Communication traffic can be squeezed when the number of connections increases. Therefore, the above problem can be solved by prohibiting the connection form.

Also, attach requests from ineligible candidate units can be repeated while the candidate unit is close to the downstream node unit, allowing smooth communication of the downstream node unit. Processing may be hindered. From the viewpoint of preventing such a problem, it is effective to configure the communication control unit to include the following requirements.
-Unit specific information acquisition unit: When an attach request is received from a candidate unit, the unit specific information unique to the candidate unit is acquired from the candidate unit.
-Connection non-permitted unit registration control unit: When the main construction permission determination of the downstream wireless link for the candidate unit is negative, the unit specific information of the candidate unit is input to the connection non-permitted unit registration unit (Fig. 3: Rejection list 305rr). ).
-Unit specific information collation unit: When an attach request is received again from a candidate unit after executing a detach sequence, the unit specific information acquired from the candidate unit is combined with the unit specific information registered in the connection non-permitted unit registration unit. Match.
In this case, the temporary radio link construction control unit accepts the attach request from the candidate unit and accepts the temporary radio if the unit specific information that matches the unit specific information acquired from the candidate unit is not registered in the connection unauthorized unit registration unit. A link is constructed, and if the unit specific information is already registered in the connection non-permitted unit registration unit, the attach request from the candidate unit is rejected.

According to the above configuration, at the time of the first attach request from the ineligible candidate unit, the unit specific information is acquired from the candidate unit and registered as the connection non-permitted unit, so that the second and subsequent attach requests are made. Occasionally, by collating the unit specific information, it is possible to avoid the cooperative connection with the candidate unit in the form of rejecting the attach. As a result, it is possible to prevent the attachment sequence for constructing the temporary radio link from being executed at the second and subsequent attachment requests from the ineligible candidate unit, and the communication processing of the node unit at the downstream end is hindered. It should be noted that the candidate unit determined to be "ineligible" at a certain point may also be eliminated from the ineligible factor over time. In this case, the connection non-permitted unit registration control unit registers the unit specific information in the connection non-permitted unit registration unit only for a predetermined registration valid period, and registers the unit specific information as the registration valid period expires. By configuring to invalidate the state, it is possible to accept the cooperative connection via the wireless link from the candidate unit whose ineligibility factor has been eliminated without any problem.

The unit specific information acquisition unit can be configured to acquire the IMSI information for connecting and authenticating the candidate unit as the unit specific information in the attach sequence to the candidate unit. The IMSI is the specific information of the contract subscriber written in the SIM (Subscriber Identity Module) card of the candidate unit, for example, which is attached to and detached from the relay wireless communication unit 9. In the LTE attach sequence, the procedure is specified to transmit the IMSI from the terminal device to the node unit at the downstream end via the PUSCH for subscriber authentication of the terminal device such as the UE 5 or the relay wireless communication unit 9. By using this, there is an advantage that unit specific information can be easily acquired from the candidate unit.

When the temporary radio link construction control unit rejects the attach request from the candidate unit, the temporary radio link construction control unit sends the candidate unit notification information prompting the candidate unit to extend the period until the next attach request made to the candidate unit. Can be configured to. As a result, reattach requests frequently arrive at short intervals from the candidate unit that once rejected the attach request (such an operation also hinders the operation of registering the unit specific information in the rejection list 305rr (FIG. 3). Can be prevented. As the notification information, a reason code (Cause Code: transmitted using PDSCH) returned from the node unit at the downstream end to the relay wireless communication unit 9 which is a terminal device on the candidate unit side can be adopted. .. For example, in the LTE specifications, candidate units that have received reason code 22 (Congestion: congestion) are allowed to reattach to the radio base station unit 4 only after a certain period of time in which the congestion state is expected to be resolved. Therefore, processing suitable for the above purpose is realized. It is also effective to use the reason code 15 (move to another tracking area candidate). In the LTE specifications, the candidate unit that received the reason code attempts to attach to the radio base station unit 4 that belongs to another tracking area, so it takes time to request the attach again to the node unit at the downstream end that was rejected. Can be stretched.

Hereinafter, an example of the specific processing flow will be described with reference to FIGS. 22 to 24. Here, an example is taken in which the wireless communication unit 1 (A) is a candidate unit and is connected to the wireless base station unit 4 of the wireless communication unit 1 (B) which is a node unit at the downstream end. First, as shown in FIG. 22, the wireless communication unit 1 (A) as a candidate unit is the wireless cooperation protocol layer module 305p (wireless link management module 305pj) of the EPC function unit 3, and is described above in the state before attachment. The isolated mode state has been established (M101). On the other hand, the relay wireless communication unit 9 of the wireless communication unit 1 (A) performs a cell search by transmitting a search radio wave at T101.

The radio base station unit 4 of the radio communication unit 1 (B) returns the notification information indicating that the search radio wave has been received to the relay radio communication unit 9 of the radio communication unit 1 (A) using a MIB or SIB. (T102). In response to this, the relay radio communication unit 9 makes an attach request to the radio base station unit 4 at T103. At T104, the attach sequence detailed in FIG. 16 is executed and a temporary radio link is constructed.

The relay wireless communication unit 9 of the wireless communication unit 1 (A) notifies the wireless cooperation protocol layer module 305p of the wireless link update information indicating the provisional wireless link construction. As a result, the operation mode of the wireless communication unit 1 (A) shifts to the cooperation mode (M102). In response to this, the wireless linkage protocol layer module 305p activates the routing management module 305pr and the topology management module 305pt, and the routing management information (see U101) described with reference to FIG. 14A and the topology management information described with reference to FIG. 15 (see U101). U201) is transmitted to the wireless cooperation protocol layer module 305p of the EPC function unit 3 of the wireless communication unit 1 (B) by the cooperation notification packet. In the figure, the thick broken line indicates the flow of information via the linked notification packet.

In the wireless linkage protocol layer module 305p, the connection topology form between the wireless communication unit 1 (A) and the wireless communication unit 1 (B) indicated by the received topology management information is analyzed by the topology management module 305pt, and corresponds to the prohibited connection form. Determine if not (T107: Topology Update Inquiry). FIG. 22 shows a case where the prohibited connection form such as the formation of the endless portion (loop) described above is applicable, and the topology management module 305pt rejects the topology update (T108). Further, the IMSI acquired for authentication from the relay wireless communication unit 9 of the wireless communication unit 1 (A) is registered in the rejection list 305rr for a certain period (T109).

In response to this flow, the wireless linkage protocol layer module 305p requests the EPC function unit 3 to disconnect (detach) the temporary wireless link (T110). The control information related to T107 to T110 is exchanged by the wireless communication unit 1 (B) by transmitting and receiving cooperation notification packets inside the EPC function unit 3 on the wireless cooperation protocol layer.

Then, in T111, the EPC function unit 3 of the wireless communication unit 1 (B) executes a detachable sequence with the relay wireless communication unit 9 of the wireless communication unit 1 (A), and the temporary wireless link is disconnected. The relay wireless communication unit 9 of the wireless communication unit 1 (A) notifies the wireless cooperation protocol layer module 305p of the wireless link update information indicating the temporary wireless link disconnection. As a result, the wireless link is updated to the disconnected state (T112), and the operation mode shifts to the isolated mode (M103). The IMSI registered in the rejection list 305rr is deleted or invalidated after the above-mentioned fixed period has elapsed.

Next, FIG. 23 shows an example of processing when the connection topology form between the wireless communication unit 1 (A) and the wireless communication unit 1 (B) does not correspond to the prohibited connection form. The processes from T101 to T103 in FIG. 22 are carried out in the same manner in this case as well, but are not shown in FIG. 23. Further, the processing from T304 to T306 in FIG. 23 is the same as the processing from T104 to T106 in FIG.

In FIG. 23, after the temporary wireless link is constructed (T304) and the wireless link is updated (T305), the EPC function unit 3 of the wireless communication unit 1 (B) that has received the routing management information and the topology management information (T306). ), The wireless cooperation protocol layer module 305p executes the wireless link update indicating the temporary wireless link construction at T307. Further, in T308, the connection topology form indicated by the received topology management information is analyzed by the topology management module 305pt (T308: topology update inquiry). The topology management module 305pt accepts the connection topology form at T309 and updates the topology management table 305tt (topology update acceptance). On the other hand, the wireless linkage protocol layer module 305p inquires the routing management module 305pr at T310 whether or not the contents of the received routing management information are acceptable (routing update inquiry). The routing management module 305pr accepts the content of the routing management information at T311 and updates the routing management table 305f (routing update acceptance). The EPC function unit 3 (wireless cooperation protocol layer module 305p) of the wireless communication unit 1 (B) transfers the updated topology management information and routing information to the EPC function of the wireless communication unit 1 (A) via the cooperation notification packet. It is transmitted to the unit 3 (wireless cooperation protocol layer module 305p). The temporary wireless link is taken over as a wireless link (cooperative wireless bearer) in the present construction state, and thereafter, transmission of user data via the wireless link is started (M303).

Finally, FIG. 24 shows a processing flow when the candidate unit (wireless communication unit 1 (A)) once rejected by the flow of FIG. 22 requests the wireless communication unit 1 (B) to attach again. It is a thing. The wireless communication unit 1 (A) is in the isolated mode (M201), and the relay wireless communication unit 9 issues an attach request to the EPC function unit 3 of the wireless communication unit 1 (B) at T201. The EPC function unit 3 of the wireless communication unit 1 (B) inquires the above-mentioned IMSI transmitted at this time to the wireless cooperation protocol layer module 305p. The topology management module 305pt of the wireless linkage protocol layer module 305p searches the acquired IMSI on the rejection list 305rr. If the received IMSI matches any of the IMSIs registered in the rejection list 305rr, T204 instructs the rejection of the attach request. As a result, the temporary wireless link is not constructed.

The EPC function unit 3 of the wireless communication unit 1 (B) assigns a reason code to the relay wireless communication unit 9 of the wireless communication unit 1 (A) at T201 and notifies the attachment rejection. The reason code number at this time is 22 (congestion), but it may be 15 (move to another tracking area) as described above.

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 WS (A), WS (B) Large vessel 2 MME
3 EPC function unit 300 User data packet 350 Linkage notification packet 301 CPU
302 RAM
303 mask ROM
304A Upstream Communication Interface 304B Downstream Communication Interface 305 Flash Memory 305a Communication Firmware 305p Wireless Linkage Protocol Layer Module 305pr Routing Management Module 305f Routing Management Table 305pt Topology Management Module 305tt Topology Management Table 305pr Rejection List 305pj Wireless Link Management Module 305b MME Entity 305c S-GW interface 305d P-GW entity 305g Channel map 306 Bus 21 Secondary battery module 22 Power supply circuit section 23 Portable housing 30, 31 Communication bus 4 Radio base station section 401 CPU
402 RAM
403 mask ROM
404 Communication interface 405 Flash memory 405a Communication firmware 406 Bus 412 Wireless communication unit 5 UE (mobile terminal)
6 S-GW
7 P-GW
8 Router 9 Relay wireless communication unit 901 CPU
902 RAM
903 mask ROM
905 Flash memory 905a Communication firmware 906 Bus 912 Wireless communication unit 50 (A), 50 (B) Cell 55 Wireless link (cooperative wireless bearer)
57 Terminal wireless bearer

Claims (13)

A wireless communication unit for performing wireless network communication with mobile terminals in accordance with the communication protocol stack specified by 3GPP (Third Generation Partnership Project).
A wireless base station unit to which the mobile terminal can be connected via a terminal wireless bearer,
An EPC (Evolved Packet Core) function unit that is connected to the radio base station unit by wire and functions as an upper network control unit for the radio base station unit.
By connecting to the EPC function unit by wire and attaching to the radio base station unit (hereinafter referred to as the upstream radio base station unit) of the upstream node unit, which is another wireless communication unit on the upstream side, the upstream side cooperative wireless bearer (hereinafter referred to as the upstream radio base station unit). Hereinafter, it is provided with a relay wireless communication unit capable of linked connection with the upstream node unit via an upstream wireless link).
The radio base station unit receives an attachment from a relay radio communication unit (hereinafter referred to as a downstream relay radio communication unit) of a downstream node unit which is another radio communication unit on the downstream side, thereby receiving a downstream cooperative radio bearer (hereinafter referred to as a downstream relay radio communication unit). , Called downstream wireless link), it is possible to connect with the downstream node unit.
The EPC function unit includes a communication firmware storage unit that stores communication firmware in which the communication protocol stack is incorporated, and a communication control unit that performs wireless network communication control by executing the communication firmware.
As a new protocol layer on the upper layer side of the transport layer on the control plane side of the communication protocol stack, the cooperation between the EPC control unit of the upstream node unit and the EPC control unit of the downstream node unit. A wireless cooperation protocol layer that handles the transmission and reception of cooperation notification information, which is notification information used to control the construction and management of wireless bearers, has been added.
The communication control unit incorporates the cooperation notification information into the cooperation notification packet defined on the wireless cooperation protocol layer, and also incorporates the cooperation notification information between the upstream node unit and the downstream node unit. A wireless communication unit including a linked notification information transmission / reception control unit that executes transmission / reception control as transmission / reception control of the linked notification packet based on the packet transmission / reception protocol defined on the transport layer. The wireless communication unit according to claim 1, wherein the cooperation notification packet is issued as an IP packet having a fixed destination address that also serves as identification information indicating that the cooperation notification packet is the cooperation notification packet. The wireless communication unit according to claim 1 or 2, wherein the transport layer in which the wireless cooperation protocol layer is constructed in the communication protocol stack is a UDP (User Datagram Protocol) layer. The communication control unit
The wireless communication unit connected to the upstream side or the downstream side of the own node unit is regarded as another node unit, and the routing management information including the node address of the mobile terminal connected to the radio base station portion of the other node unit is used as the upstream node. A routing management information reception control command unit that commands the cooperation notification information transmission / reception control unit to receive as the cooperation notification information from the unit or the downstream node unit.
Routing management that integrates the routing management information including the node address of the mobile terminal connected to the radio base station portion of the own node unit with the routing management information of the upstream node unit or the other node unit received from the downstream node unit. Information integration processing department and
A routing management information storage control unit that stores the integrated routing management information in the routing management information storage unit,
A routing management information transmission control command unit that commands the cooperation notification information transmission / reception control unit to transmit the integrated routing management information as the cooperation notification information to the downstream node unit or the upstream node unit.
By referring to the routing management information stored in the routing management information storage unit, the node address of the mobile terminal to which the user data is transferred is specified, and the user data is transferred on the user plane side of the communication protocol stack. The user data transfer control unit that controls and
The wireless communication unit according to any one of claims 1 to 3. The communication control unit
Regarding the wireless communication unit group connected to the upstream side or the downstream side of the own node unit, the upstream node unit provides the wireless connection topology information that specifies the individual wireless communication units included in the wireless communication unit group together with the connection order. Alternatively, the wireless connection topology information reception control command unit that commands the cooperation notification information transmission / reception control unit to receive the cooperation notification information from the downstream node unit.
Wireless connection topology information that updates the contents of the wireless connection topology information received from the upstream node unit or the downstream node unit in the form of incorporating the own node unit into the wireless communication unit group specified by the wireless connection topology information. Update processing unit and
A wireless connection topology information storage control unit that stores the updated wireless connection topology information in the wireless connection topology information storage unit,
It is provided with a wireless connection topology information transmission command unit that commands the cooperation notification information transmission / reception control unit to transmit the updated wireless connection topology information to the downstream node unit or the upstream node unit.
The wireless communication unit according to claim 4, wherein the user data transfer control unit controls transfer of the user data based on the wireless connection topology information stored in the wireless connection topology information storage unit. The communication control unit
Prior to the main construction of the downstream wireless link with the candidate unit, which is a wireless communication unit that is a candidate for the downstream node unit, the attachment request from the candidate unit is received from the candidate unit. The temporary wireless link construction control unit that constructs the temporary wireless link,
The cooperation notification information transmission / reception control unit is informed that the candidate unit receives the determination reference information referred to in the main construction permission determination of the downstream radio link as the cooperation notification information from the candidate unit via the provisional radio link. Judgment reference information reception control command unit to command,
A downstream radio link main construction permission determination unit that determines the main construction permission of the downstream radio link for the candidate unit based on the received determination reference information.
If the result of the present construction permission determination is affirmative, the provisional radio link is transferred to the present construction state as the downstream radio link, while if the result of the present construction permission determination is negative, the provisional radio link is said. The wireless communication unit according to any one of claims 1 to 5, further comprising a downstream wireless link construction control unit that executes a detachable sequence for resolving the wireless link construction state. The determination reference information specifies each wireless communication unit included in the wireless communication unit group together with the connection order for the wireless communication unit group including the candidate unit connected to the downstream side or the upstream side of the own node unit. Contains wireless connection topology information
The downstream wireless link main construction permission determination unit of the downstream wireless link to the candidate unit when the connection form of the wireless communication unit group indicated by the wireless connection topology information corresponds to a predetermined prohibited connection form. The wireless communication unit according to claim 6, which determines that this construction is not permitted. The wireless communication unit according to claim 7, wherein the prohibited connection form is a connection form in which the same wireless communication unit as any of the other node units connected to the upstream side of the own node unit is the candidate unit. The communication control unit
A unit-specific information acquisition unit that acquires unit-specific information unique to the candidate unit from the candidate unit in response to receiving the attach request from the candidate unit.
When the determination of permission to construct the downstream wireless link for the candidate unit is negative, the connection non-permitted unit registration control unit that registers the unit specific information of the candidate unit in the connection non-permitted unit registration unit, and the connection non-permitted unit registration control unit.
A unit that collates the unit identification information acquired from the candidate unit with the unit identification information registered in the connection non-permitted unit registration unit when the attachment request is received again from the candidate unit after the execution of the detach sequence. Equipped with a specific information collation unit
When the unit identification information collating with the unit identification information acquired from the candidate unit is not registered in the connection non-permitted unit registration unit, the temporary radio link construction control unit accepts the attach request from the candidate unit. The wireless communication unit according to claim 7 or 8, wherein a temporary wireless link is constructed and the attach request from the candidate unit is rejected when the unit specific information is registered in the connection non-permitted unit registration unit. The connection non-permitted unit registration control unit registers the unit specific information in the connection non-permitted unit registration unit only for a predetermined registration valid period, and when the registration valid period expires, the unit specific information of the unit specific information is registered. The wireless communication unit according to claim 9, which invalidates the registration status. The 9th or 10th claim, wherein the unit specific information acquisition unit acquires IMSI (International Mobile Subscriber Identity) information for connecting and authenticating the candidate unit in the attach sequence to the candidate unit as the unit specific information. Wireless communication unit. The temporary radio link construction control unit rejects the attach request from the candidate unit, and the candidate unit is provided with notification information prompting the candidate unit to extend the period until the next attach request made to the candidate unit. The wireless communication unit according to any one of claims 9 to 11 to be transmitted to. 3 A wireless communication unit for performing wireless network communication with a mobile terminal in accordance with the communication protocol stack specified by the GPP (Third Generation Partnership Project), and a wireless base to which the mobile terminal can connect via a terminal wireless bearer. An EPC (Evolved Packet Core) functional unit that is wiredly connected to the local unit and the wireless base station unit and functions as an upper network control unit for the wireless base station unit, and another upstream side while being wiredly connected to the EPC functional unit. By receiving an attachment from the radio base station section of the upstream node unit, which is a wireless communication unit (hereinafter referred to as the upstream radio base station section), the upstream node via the linked radio bearer on the upstream side (hereinafter referred to as the upstream radio link). The wireless base station unit is provided with a relay wireless communication unit capable of linked connection with the unit, and the wireless base station unit is referred to as a relay wireless communication unit (hereinafter referred to as a downstream relay wireless communication unit) of a downstream node unit which is another wireless communication unit on the downstream side. ) Allows linked connection with the downstream node unit via the downstream linked wireless bearer (hereinafter referred to as downstream wireless link), and the EPC functional unit incorporates the communication protocol stack. It is equipped with a communication firmware storage unit that stores the communication firmware and a communication control unit that performs wireless network communication control by executing the communication firmware, and is new to the upper layer side of the transport layer on the control plane side of the communication protocol stack. As a protocol layer, of the cooperation notification information which is the notification information used for controlling the construction and management of the cooperation radio bearer between the EPC control unit of the upstream node unit and the EPC control unit of the downstream node unit. A wireless cooperation protocol layer that handles transmission and reception is added, and the communication control unit incorporates the cooperation notification information into the cooperation notification packet defined on the wireless cooperation protocol layer, and is between the upstream node unit or the above. It is provided with a linked notification information transmission / reception control unit that executes transmission / reception control of the linked notification information with the downstream node unit as transmission / reception control of the linked notification packet according to the packet transmission / reception protocol specified on the transport layer. The wireless communication unit consists of a group of wireless communication units connected to each other by the cooperative wireless bearer.
The mobile terminal connected to the first wireless communication unit forming any one of the plurality of wireless communication units via the terminal wireless bearer, and the terminal to the second wireless communication unit forming any other arbitrary one. The mobile terminal connected via a wireless bearer connects two or more wireless communication units from the first wireless communication unit to the second wireless communication unit, and the cooperative wireless bearer that connects the wireless communication units to each other. A wireless network system characterized in that user data is transmitted and received via and.

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