JP6315914B2 - Method and apparatus for accessing broadcast distribution information - Google Patents

Description

  The present invention relates to a method and apparatus for efficiently accessing broadcast information distributed in a wireless network from user equipment.

Conventionally, in an in-cell broadcast (CBS) that simultaneously broadcasts to mobile phones in the communication area of a base station antenna, information transmitted from an information distribution server is sent to a short message service center, backhaul It is transmitted from the base station antenna via the RNC in the network. The mobile phone that has received the intra-cell broadcast processes the received broadcast information as communication information, and displays, for example, information transmitted in the intra-cell broadcast message on the display screen as character information. In 3GPP (3 ^rd Generation Partnership Project) cellular radio network with a standard compatible to all subscriber terminals that are located in specific set of one or more cells on the broadcast channel that is shared On the other hand, CBS (Cell Broadcast Service) that enables message transmission at a low bit rate is defined as a message-based information service.

  2. Description of the Related Art In recent years, technology has been developed that uses emergency broadcast information such as CBS (Cell Broadcast Service) to distribute emergency earthquake information and advertisements to a plurality of mobile communication terminals using a mobile communication network. For example, a technique is known in which, when emergency earthquake information is transmitted from an earthquake monitoring server, the emergency earthquake information is format-converted in the earthquake information distribution server and broadcast to mobile communication terminals. In a cellular radio network compatible with the 3GPP standard, as one form of the information message delivery service using the above-described intra-cell broadcast function, urgency such as disaster occurrence information is provided to a plurality of user terminals in the cell. In recent years, services for rapidly delivering high information simultaneously are known. In 3GPP, a method for distributing an earthquake / tsunami warning from a mobile communication network to a mobile terminal is defined. Various techniques for realizing this have been proposed. According to the 3GPP regulations, the information sender of the earthquake and tsunami warning service displays the ETWS (Earthquake and Tsunami Warning System) primary message, which is the first report of the earthquake and tsunami warning, on the mobile terminal within 4 seconds of the notification period. It is required to do. Further, the mobile terminal is required to display it immediately after receiving the ETWS primary message.

  In the CBS function implemented by the cellular radio network, the ETWS primary message described above is transmitted by a CBS PDU which is a protocol data unit used for the purpose of transmitting an intra-cell broadcast information message. A conventional cellular radio network compatible with the 3GPP standard is for uniformly distributing broadcast information messages transmitted from an information distribution server simultaneously to a specific distribution destination area including a plurality of cells and a plurality of wireless LAN areas. In addition, the RNC accommodates the plurality of cells and the wireless LAN area. Therefore, the broadcast information message transmitted from the information distribution server is routed via the RNC.

  When highly urgent information such as disaster information is distributed by in-cell broadcast using a CBS function or the like, the number of distribution destination terminals is large, which may cause congestion in the wireless network. Therefore, Patent Document 1 discloses a technique for alleviating traffic bursts of distribution information in a radio access network without increasing the number of RNC facilities. In the invention described in Patent Document 1, when the information distribution server receives an information distribution request from a user terminal registered in advance as an information distribution source using the CBS function via the base station and the RNC, the information distribution server The database is inquired of the distribution cell area specification and its priority from the included cell identifier where the user terminal is located and information contents. In the invention described in Patent Document 1, the information distribution server further transmits an information distribution request with a time lag in order of priority according to the specification of the distribution destination cell area obtained from the database and the priority information thereof. . In accordance with this information distribution request, the RNC performs information distribution with the time lag to the base station of each cell by the CBS function.

  In addition, when highly urgent information such as disaster information is distributed by in-cell broadcast using a CBS function or the like, high certainty without receiving errors is required for receiving distribution information by each user terminal. Therefore, Patent Document 2 discloses a technique for providing a mechanism for improving a reception success rate in notification of emergency disaster information from a mobile communication network to a mobile terminal. In the invention described in Patent Document 2, the wireless communication system includes a base station and a mobile terminal. In the invention described in Patent Document 2, the base station divides emergency disaster message data to be distributed to the mobile terminal into a plurality of pieces, calculates parity for the divided data, and distributes the data and parity to the mobile terminal. The mobile terminal receives the data and parity from the base station, restores the emergency disaster message from the data and parity, and presents it to the user.

  As a service similar to the message distribution service based on the above-mentioned intra-cell broadcast, a service that distributes corporate advertisements, coupon information for customers, etc. to all wireless LAN terminals located within the communication area of the wireless LAN access point Has also become popular. In a cellular wireless network or a wireless LAN network, in order to use such a broadcast type message distribution service from a wireless terminal, a wireless access network connected from the wireless terminal is set by the user between the cellular wireless network and the wireless LAN. It is common to switch according to the situation. In order to enable such a usage mode of a wireless terminal, a user may access a wireless network using a multi-mode wireless terminal equipped with two wireless interface circuits respectively corresponding to a cellular wireless network and a wireless LAN. It is a premise. In this case, the multi-mode wireless terminal establishes a plurality of radio bearers connected to each of the cellular radio network and the wireless LAN that can be used at the same time, and switches the plurality of radio bearers according to the situation for communication.

JP 2009-005310 A JP 2012-060377 A

  However, depending on the position where the multi-mode wireless terminal is staying, a carrier signal from the cellular base station may not be detected due to a local channel state, radio wave interference, or an obstacle at the position. Such a case may occur even if the position where the multimode terminal is staying is relatively close to any cellular base station. In addition, when the multi-mode wireless terminal is being used in a vehicle moving at high speed, it becomes difficult to communicate with a certain signal quality due to frequent handovers, etc., so that the wireless connection from the multi-mode wireless terminal to the cellular wireless network There can be situations where this is virtually impossible. At the same time, in such a situation, there may be a case where the multi-mode wireless terminal can be connected to the wireless LAN provided in the vehicle with good signal quality.

  Therefore, even a multi-mode wireless terminal equipped with two wireless interfaces corresponding to a cellular wireless network and a wireless LAN may temporarily be unable to connect to the cellular wireless network. In this case, it is impossible to receive a message delivery service (such as ETWS) that is executed based on the intra-cell broadcast function provided only by the cellular radio network, such as the CBS function, from the multimode radio terminal.

  In addition, some mobile information terminals such as laptop computers, tablet terminals, and handheld devices are equipped with wireless LAN interface circuits but not equipped with wireless interface circuits for cellular wireless networks. However, it is quite popular. On the contrary, some cellular mobile telephones that are equipped with only a wireless interface circuit for a cellular wireless network and do not have a wireless LAN interface circuit are still quite popular. Also in this case, there arises a problem that the information distribution service using the CBS function provided only by the cellular radio network cannot be received, or the broadcast distribution service provided only within the wireless LAN cannot be received.

  And in the invention disclosed by patent document 1 and patent document 2, it is impossible to overcome the above-mentioned problem.

  Furthermore, in a service that distributes disaster occurrence information and the like to an unspecified number of wireless terminals based on an in-cell broadcast function such as the CBS function, it is rich for displaying a disaster map (hazard map) on the screen of the wireless terminal.・ Content information is considered to be relatively large distribution information of several hundred kilobytes or more. However, in disaster information delivery services such as ETWS standardized in 3GPP GERAN (GSM EDGE Radio Access Network), an ETWS primary message that broadcasts disaster occurrence information to wireless terminals in a cell using the CBS function is It has a size of only 56 octets. Therefore, it is impossible to broadcast-deliver to the wireless terminals in the cell by directly including the large-capacity rich content information as described above in the ETWS primary message.

  In such a case, in the prior art, the URL or URI of the Web server or content providing server that stores the above-described rich content information is described in the message broadcast-distributed within the communication area of the message delivery destination. It is generally done. However, in this case, if the user of the wireless terminal that received the message distribution tries to access the Web server or the content providing server based on the URL or URI included in the message, the user is located in the communication area of the message distribution destination. All users simultaneously access the Web server and the content providing server at the same time. As a result, a congestion state occurs in the cellular wireless network, or a content provider server in which accesses from a large number of wireless terminals located in the communication area of the message distribution destination are concentrated may be overloaded.

  The invention described in Patent Document 1 assigns priority to each type of traffic distributed by broadcast in order to prevent concentration of access to the content provider server and occurrence of normal congestion in the wireless network as described above. The transmission timing of broadcast traffic with lower priority is delayed. However, in the invention described in Patent Document 1, the disaster occurrence information distribution and the like are extremely urgent broadcast distributions, and thus it is necessary to guarantee a quick and reliable distribution without delay. Therefore, when there is a need to provide multiple types of broadcast delivery services with high urgency in the same cellular radio network as in the case of disaster occurrence information delivery, there is contention for priority among these multiple broadcast delivery services. Cause problems.

  In view of the above-described problems, the present invention is a multimode wireless terminal that is temporarily unable to connect to a cellular wireless network or a wireless terminal that does not have a means for connecting to a cellular wireless network. It is an object of the present invention to realize a mechanism for receiving an information distribution service based on a provided intra-cell broadcast function (CBS function or the like). Similarly, an object of the present invention is to realize a mechanism that enables a cellular wireless terminal that does not have a wireless LAN interface circuit to receive a broadcast distribution service provided only within the wireless LAN. Further, the present invention provides a wireless network for executing access to a large amount of information such as rich contents based on a broadcast distribution function for all users who are present in a message information distribution destination communication area. Another object of the present invention is to realize a mechanism that prevents concentration of access from a large number of wireless terminals to a content provider server and contention of communication priority.

  As described above, the first aspect of the present invention is a method for distributing a broadcast message distributed in a first wireless communication network to one or more wireless terminals connectable only to the second wireless communication network. The access point in the second wireless communication network is connected to the first wireless communication network via a relay station capable of relaying a wireless signal from the first wireless communication network to the second wireless communication network. Receiving the broadcast message broadcast from the wireless communication network; the access point receiving the broadcast message broadcasts the broadcast message in the second wireless communication network; And converting the format-converted broadcast message to the one or more wireless terminals by the access point. .

  Furthermore, in the first aspect of the present invention, the relay station has two connection means connectable to each of the first wireless communication network and the second wireless communication network, It is a multimode wireless device that is wirelessly connected to both the first wireless communication network and the second wireless communication network.

  According to a second aspect of the present invention, there is provided a method for distributing related information attached to a broadcast message distributed to one or more wireless terminals in the wireless communication network to the one or more wireless terminals. The access point in the second wireless communication network is connected to the first wireless communication network via a relay station capable of relaying a wireless signal from the first wireless communication network to the second wireless communication network. Receiving the broadcast message broadcast from the wireless communication network; requesting that the related information should be acquired when the link link of the related information is included in the broadcast message The access point receives from the relay station; in response to the reception of the request, the access point downloads the related information from the provider server of the related information via the provider link And cache the local information in the local station; and the access point broadcasts the related information to one or more wireless terminals in the second wireless communication network; The second wireless communication network can download the related information at a higher speed than the first wireless communication network.

  Furthermore, in the second aspect of the present invention, the relay station has two connection means connectable to each of the first wireless communication network and the second wireless communication network, It is a multimode wireless device that is wirelessly connected to both the first wireless communication network and the second wireless communication network.

  Furthermore, in the second aspect of the present invention, the related information includes large-capacity content information related to message contents notified by the broadcast message, and the providing server can provide the large-capacity content. And the provider link includes a URL or URI indicating the location of the large-capacity content stored in the content server.

  As described above, according to the present invention, a multimode wireless terminal that is temporarily unable to connect to a cellular wireless network or a wireless terminal that does not have a means for connecting to the cellular wireless network is provided only by the cellular wireless network. An information distribution service based on an in-cell broadcast function (such as a CBS function) can be received. Similarly, the present invention can enable a cellular wireless terminal that does not have a wireless LAN interface circuit to receive a broadcast distribution service provided only in the wireless LAN. In addition, the present invention, when executing access to large-capacity information such as rich content based on the broadcast distribution function for all users who are present in the communication area to which the message information is distributed, Concentration of access from a large number of wireless terminals to the wireless network or content provider server and contention of communication priority can be prevented.

Configuration diagram of a broadcast distribution system as a basis for realizing the present embodiment in a cellular radio network Device configuration of wireless terminal used in this embodiment The figure explaining the communication operation | movement of the 1st Example which concerns on this Embodiment Event flow diagram showing the flow of signal processing operation in the first example of the present embodiment The figure which shows the network connection between the internet and a radio | wireless terminal regarding the 2nd Example which concerns on this Embodiment The figure explaining the communication operation of 2nd Example which concerns on this Embodiment Event flow diagram showing the flow of signal processing operations in the second example of the present embodiment

  Hereinafter, the present embodiment will be described with reference to the drawings. In this embodiment, first, an outline of the first example and the second example will be described. Next, a network configuration of a broadcast distribution system serving as a basis for realizing the present embodiment in a cellular radio network will be described with reference to FIG. Next, with reference to FIG. 2, device configurations of the multimode wireless terminal and other wireless terminals used in the present embodiment will be described. Finally, details of the first and second embodiments will be described with reference to FIGS.

<1> Overview of First Example and Second Example According to this Embodiment A first example according to this embodiment will be described as follows. As described above, even a multimode wireless terminal is equipped with a terminal that is temporarily unable to connect to a cellular wireless network, or a wireless LAN interface circuit, and a means for connecting to the cellular wireless network. The wireless terminal that does not have is referred to as a wireless LAN dedicated terminal in the following description. Conversely, a wireless terminal equipped with only a wireless interface circuit for connecting to a cellular wireless network and having no means for connecting to a wireless LAN will be referred to as a cellular dedicated terminal in the following description.

  The first example according to the present embodiment exemplifies a mechanism that enables a wireless LAN dedicated terminal to receive a message distribution service based on an intra-cell broadcast function unique to a cellular radio network such as a CBS function. In order to realize such a mechanism, in the first embodiment, a multimode wireless terminal that is simultaneously connected to a base station of a cellular wireless network and a wireless LAN access point is used as a relay station. Specifically, the multi-mode wireless terminal functioning as the relay station described above relays a message distributed from the cellular base station to the wireless LAN access point based on the intra-cell broadcast function in the cellular wireless network. Subsequently, the wireless LAN access point broadcasts the relayed message to all the wireless terminals located within the communication area of the local station.

  As a modification of the first embodiment, a cellular dedicated terminal can receive a message distribution service based on an in-communication area broadcast function provided only within a wireless LAN, such as a coupon distribution service provided by a wireless LAN service provider. It is also possible to realize a mechanism to do so. When implementing such a mechanism, similarly to the above, the wireless LAN access of the message distribution source is performed using a multimode wireless terminal that is simultaneously connected to the base station of the cellular wireless network and the wireless LAN access point as a relay station. It is possible to relay and transmit the broadcast distribution message within the communication area between the point and the cellular base station.

  In the second example according to the present embodiment, when a message is broadcast to a wireless LAN dedicated terminal or a cellular dedicated terminal based on a broadcast function in a communication area unique to a cellular wireless network or a wireless LAN, the message An example of a mechanism for efficiently distributing large-capacity content information, which is related information incidental to, is shown. That is, in the second embodiment, the large-capacity content information attached to the message broadcast-distributed to all terminals in the wireless LAN communication area is broadcast-distributed to all the terminals by the same method as the first embodiment. In this case, a mechanism for preventing access load and congestion on the wireless network side is disclosed.

  Specifically, first, using a multimode wireless terminal that is simultaneously connected to a base station of a cellular radio network and a wireless LAN access point as a relay station, the cellular base station of the message distribution source, the wireless LAN access point, Intra-cell broadcast delivery messages are relayed between Subsequently, when the wireless LAN access point relayed with the message includes a URL or URI indicating a link to the provider of the large-capacity content information described above, the URL or URI is displayed. The large-capacity content is downloaded to a cache memory in the local station and temporarily stored. Finally, the wireless LAN access point broadcasts the temporarily stored large-capacity content information to all wireless terminals located within the communication area of the local station.

  Note that the cellular base station used in the first and second embodiments may be an eNodeB, a BTS, or the like in the E-UTRAN standard that 3GPP is standardizing.

<2> Network Configuration of Broadcast Distribution System A configuration of a distribution system that implements broadcast distribution of message information based on the CBS function in a cellular radio network will be described below with reference to FIG. This distribution system is used as a network infrastructure for realizing the information message broadcast function according to the present embodiment in a cellular radio network.

  The broadcast distribution system shown in FIG. 1 assumes a service in which an alarm system device distributes information such as disaster occurrence information to a nearby cell area accommodated in the RNC 6 using a CBS (Cell Broadcast Service) function. The information distribution request (P1) including distribution characteristics from the wireless access network is generated from the alarm system device.

  In the information distribution server 7, the alarm system device is registered in advance as a source of information distribution using the CBS function. Therefore, the information distribution server 7 is registered in advance as a source of information distribution using the CBS function. When the information distribution request (P1) from the alarm system device is received via the base station 2 and the RNC 6, the cell identifier and information distribution in the received content (P2) where the user (terminal 1) is located Based on the distribution characteristics included in the request (P1), the database 8 is queried for information specifying the distribution target cell area (P3, P4).

  The information distribution server 7 uses the information provided from the alarm system device as an information distribution request (P5-1, P6-1, P7-1) according to the distribution target cell area specific information obtained from the database 8 as the RNC 6 Send to. In accordance with this information distribution request, the RNC 6 distributes information provided from the alarm system device to the base stations 2 to 5 of each cell by the CBS function (P5-2, P6-2, P7-). 2).

  In the broadcast distribution system described above, the alarm system device may be incorporated in the information distribution server 7, or may be any network device or server in a wireless network not shown in FIG. It is also possible to use the terminal 1 shown in FIG.

<3> Device Configuration of Wireless Terminal Next, referring to FIG. 2, the multi-mode wireless terminal 10m used for carrying out the present embodiment and others such as the wireless LAN dedicated terminal and the cellular dedicated terminal described above The device configuration of the wireless terminal 10s will be described.

  In FIG. 2, the multi-mode wireless terminal 10 m receives input / output data between an antenna 101 that transmits and receives wireless signals, a wireless interface 102 a connected to the antenna 101, a wireless interface 102 b, a memory 103, a control processor 104, and a control processor 104. A user input / output device 105 that controls a user interface between the user and the wireless terminal 10 while exchanging data, a storage 106 that is a permanent storage medium that stores setting parameters of the wireless terminal 10m, and a bus 107 Is done. The above-described wireless interface 102 a, wireless interface 102 b, memory 103, control processor 104, user input / output device 105, and storage 106 are connected to each other via a bus 107.

  Each of the wireless interface 102a and the wireless interface 102b converts the received RF signal by frequency down-converting, digitizing, demodulating, and decoding, thereby converting it into digital information and providing it for subsequent information processing. In contrast, each of the wireless interface 102a and the wireless interface 102b converts the digital information generated in the multi-mode wireless terminal 10m into an RF signal by encoding, modulating, and frequency up-converting. Provided to antenna 101 for wireless transmission. The wireless interface 102a is configured to execute wireless signal transmission / reception processing corresponding to the cellular wireless network, and the wireless interface 102b is configured to execute wireless signal transmission / reception processing compatible with the wireless LAN network.

  The memory 103 stores digital information exchanged between the wireless interface 102a and the wireless interface 102b with a control processor 104 described later, a program for controlling the entire wireless terminal 10, and the like.

  The control processor 104 reads the program from the memory 103, controls the entire multi-mode wireless terminal 10m, generates digital information transmitted from the antenna 101 via the wireless interface 102a and the wireless interface 102b, and controls the wireless interface 102a and the wireless interface 102b. Further processing of the digital information received from the antenna 101 is executed.

  The control processor 104 selectively enables one of the wireless interface 102a and the wireless interface 102b, and exchanges digital information via the bus 107 only through the enabled wireless interface, thereby enabling a specific wireless access. The network can be selectively used for communication.

  The user input / output device 105 exchanges input / output data between a screen display display or keypad provided on the wireless terminal 10 and the control processor 104, and at the same time, a user between the user and the multi-mode wireless terminal 10m.・ Control the interface. In addition, the user input / output device 105 is related to the change via the bus 107 when the device state or input / output status of the screen display or keypad provided on the multi-mode wireless terminal 10m changes. The interrupt processing is instructed to the control processor 104. In order to enable such interrupt control, the user input / output device 105 has a function of electrically monitoring input / output device states such as a screen display and a keypad managed by the user input / output device 105.

  The device configuration of another wireless terminal 10s corresponding to the wireless LAN dedicated terminal or cellular dedicated terminal used in the present embodiment is equipped with only one of the wireless interface 102a and the wireless interface 102b in FIG. Except for this point, the device configuration is the same as that of the multimode wireless terminal 10m.

<4> First Example According to this Embodiment The first example enables a wireless LAN dedicated terminal to receive a message distribution service based on an intra-cell broadcast function unique to a cellular radio network such as a CBS function. Illustrates the mechanism. In order to realize such a mechanism, in the first embodiment, a multimode wireless terminal that is simultaneously connected to a base station of a cellular wireless network and a wireless LAN access point is used as a relay station.

  Specifically, first, the multi-mode wireless terminal 10m (FIG. 2) functioning as the relay station described above transmits a message distributed from the cellular base station based on the intra-cell broadcast function in the cellular wireless network to the cellular radio. The data is received via the network wireless interface circuit 102a (FIG. 2). Subsequently, the multi-mode wireless terminal 10m relays the received message to the wireless LAN access point via the wireless LAN wireless interface circuit 102b. Subsequently, the wireless LAN access point broadcasts the relayed message to all the wireless terminals located within the communication area of the local station. At this time, a wireless LAN dedicated terminal may be included in all the wireless terminals located in the communication area of the wireless LAN access point.

  FIG. 3 shows a flow of the above-described series of radio signals between the cellular base station, the wireless LAN access point, and the multi-mode wireless terminal 10m. FIG. 4 is an event flow diagram for explaining the flow of signal processing operations among the cellular base station, the wireless LAN access point, and the multimode wireless terminal 10m. Hereinafter, the flow of a series of signal processing operations in the first embodiment will be described with reference to FIGS. 3 and 4.

  In FIG. 3, the cellular base station 90 that has received a message to be distributed based on the CBS function from the cellular core network 51 constituting the cellular radio network broadcasts the message into a cell covered by the own station, and performs multimode. The wireless terminal 10m receives the broadcast message (step S1 in FIG. 4). 3, the multi-mode wireless terminal 10m includes two types of wireless interface circuits 102a and 102b (FIG. 2) that can be connected to both the cellular base station 90 and the wireless LAN network access point 91 under the cellular wireless network. ).

  Subsequently, the multi-mode wireless terminal 10m that has received the delivery message turns on the power of the wireless LAN interface 102b (FIG. 2), which is a wireless interface circuit connectable to the wireless LAN (step S2 in FIG. 4). Thereafter, when the multimode wireless terminal 10m detects the beacon signal of the wireless LAN access point 91, the multimode wireless terminal 10m responds by returning a Probe Response frame to the received beacon signal. As a result, one association is established between the multimode wireless terminal 10m and the wireless LAN access point 91 as a wireless transmission channel for subsequent wireless traffic transmission (step S3 in FIG. 4). At that time, the multi-mode wireless terminal 10m transmits the message broadcasted from the cellular base station 90 in the above-described Probe Response frame to the wireless LAN access point 91. Even when an association has already been established between the multi-mode wireless terminal 10m and the wireless LAN access point 91, similarly, the above-described delivery message is included in the Probe Response frame to perform wireless LAN access. -It is possible to transmit to the point 91 (step S4 of FIG. 4).

  As described above, the multi-mode wireless terminal 10 m can serve as a relay station that relays the message broadcast-distributed from the cellular base station 90 to the wireless LAN access point 91. Note that the wireless LAN access point 91 in FIG. 3 is one or more neighboring wireless LAN access points located at a distance that allows wireless communication with good signal quality with the multi-mode wireless terminal 10m. Further, when the multi-mode wireless terminal 10m has an access point function or a tethering function as a part of the terminal function, other multi-mode wireless terminal 10m is located in the vicinity where good communication with the multi-mode wireless terminal 10m is possible. It is also possible to relay the delivery message described above to the wireless LAN dedicated terminal.

  In the embodiment described above, the above-described Probe Response frame is used as a transmission means when the multi-mode wireless terminal 10m relays the above-described message to the wireless LAN access point 91. However, in another alternative embodiment, a message frame defined in IEEE 802.11k, which is being standardized by 3GPP, may be used to relay the above message to the wireless LAN access point 91. Is possible. Specifically, it is as follows. According to the IEEE802.11k standard specifications, a plurality of wireless access points and wireless terminals constituting a single network have a relative positional relationship with each other, a state of radio wave interference for each access point, a usage state of a frequency band, etc. Can be shared by exchanging control frames. The multi-mode wireless terminal 10m can transmit a message broadcasted from the cellular base station 90 in a control frame exchanged at that time. Thereby, the multi-mode wireless terminal 10m can relay the message broadcast-distributed from the cellular base station 90 to the wireless LAN access point 91. In addition, when the multi-mode wireless terminal 10m relays a message broadcast-distributed from the cellular base station 90 to the wireless LAN access point 91, any IEEE 802.11 frame other than the above may be used as a transmission means. Is possible.

  If the message broadcasted from the cellular base station 90 is a message including highly urgent broadcast information such as an ETWS primary message, the wireless LAN access point 91 is notified as follows. Can be notified. That is, the emergency bit in the Frame Control field portion is set to ON in the MAC header or PLCP header included in the IEEE802.11 frame that relays the relay destination message to the wireless LAN access point 91. As a result, the wireless LAN access point 91 quickly executes the reception operation and distribution operation of a highly urgent message relayed from the multi-mode wireless terminal 10m in preference to other traffic and control frame transmission / reception operations. It becomes possible.

  Subsequently, the wireless LAN access point 91 to which the distribution message is relayed from the multi-mode wireless terminal 10m broadcasts the distribution message to all the wireless terminals located in the BSS covered by the local station (step in FIG. 4). S6). At this time, the wireless LAN access point 91 can broadcast the delivery message described above by including the delivery message described above in the beacon signal frame that the local station broadcasts in the BSS at a constant period. . Specifically, the wireless LAN access point 91 has been described above by additionally defining a new IE (Information Element) for storing the delivery message described above in the frame structure of the beacon signal frame described above. The delivery message is included in the beacon signal frame.

  In another alternative embodiment, in order to perform the broadcast of the delivery message described above, the wireless LAN access point 91 is a new broadcast frame that is addressed to the broadcast address and includes the delivery message described above. May be generated. In this case, the wireless LAN access point 91 transmits the generated broadcast frame toward the BSS covered by the own station.

  Note that when the delivery message is broadcast on the IEEE 802.11 frame and broadcast from the wireless LAN access point 91, the information content of the delivery message conforms to the broadcast delivery frame defined by IEEE 802.11. It is encoded again by the encoding method. Further, at this time, the information content of the delivery message is converted into a format suitable for a broadcast delivery frame defined by IEEE 802.11 (step S5 in FIG. 4).

  Subsequently, the wireless terminal 10 s located in the BSS covered by the wireless LAN access point 91 receives the distribution message broadcast toward the BSS. Thereby, even if the wireless terminal 10s is a wireless LAN dedicated terminal not equipped with the wireless interface circuit 102a (FIG. 2) that can be connected to the cellular wireless network, the wireless terminal 10s is distributed from the base station 90 of the cellular wireless network by the intra-cell broadcast function. Messages can be received.

  Finally, the wireless LAN access point 91 can further forward the above-described delivery message to nearby wireless LAN access points (such as the access points 92 and 93 shown in FIG. 3) located in the vicinity ( Step S8 in FIG. In this case, the neighboring wireless LAN access point to which the above distribution message is transferred broadcasts the above distribution message to all the wireless terminals located within the BSS of the local station.

  Such message transfer from the wireless LAN access point 91 to the neighboring wireless LAN access point is necessary in the following cases. For example, when the BSS of the wireless LAN access point 91 covers only a part of the communication area designated as the delivery destination of the delivery message, the message transfer described above is necessary. Further, for example, when the delivery destination of the delivery message is the entire ESS including the BSS covered by the wireless LAN access point 91, the message transfer described above is required.

  The wireless LAN access point 91 can use, for example, the following method in order to transfer the above-described delivery message to another nearby wireless LAN access point.

  WDS (Wireless Distribution System) is used to connect a plurality of wireless LAN access points in the same ESS in order to connect a plurality of wireless LAN access points constituting the same ESS with a wireless transmission path having a mechanism similar to that of the wireless LAN. • It defines the communication procedure for exchanging transmission frames between points. At this time, the delivery message described above is put on a transmission frame (WDS frame) exchanged between the wireless LAN access points (step S7 in FIG. 4), and another wireless LAN access in the vicinity from the wireless LAN access point 91 is performed. By transmitting to the point (step S8 in FIG. 4), the message transfer described above becomes possible.

  In another alternative embodiment, the control frame defined by the IEEE802.11F standard or the IEEE802.11s standard standardized by 3GPP and exchanged between a plurality of wireless LAN access points is distributed as described above. It can be used as a frame for transmitting a message. In particular, a control frame defined by the IEEE802.11F standard can be transmitted between the wireless LAN access points belonging to different ESSs (sub-networks) with the delivery message described above.

  Further, when the wireless LAN access point 91 transfers the distribution message to other neighboring wireless LAN access points, the distribution message is transferred a plurality of times between the plurality of wireless LAN access points. there is a possibility. In this case, it is assumed that the network connection topology formed by exchanging the transmission frame between the wireless LAN access point 91 and a plurality of neighboring wireless LAN access points has a cyclic structure. In this case, in the cyclic structure, since the delivery message is continuously turned around, an extra communication load is applied to the wireless LAN network or a congestion state occurs. In order to prevent such a situation, the wireless LAN access point 91 provides a LifeTime field in a frame for transmitting the delivery message between the wireless LAN access points. Subsequently, the wireless LAN access point 91 sets an upper limit of the number of times that the frame is relayed and transferred between the wireless LAN access points in the field. As a result, it is possible to limit the number of times that the delivery message transferred from the wireless LAN access point 91 to another nearby wireless LAN access point is relay-transferred between the wireless LAN access points.

  In the first embodiment described above, it is possible to identify each of a plurality of wireless LAN access points that transfer or broadcast a delivery message between access points and each BSS that they cover by SSID. is there.

  Further, as a modification of the first embodiment, an in-communication broadcast provided only in a wireless LAN (for example, a BSS covered by the wireless LAN access point 91) like a coupon distribution service provided by a wireless LAN service provider. It is also possible to realize a mechanism that allows a cellular dedicated terminal to receive a function-based message delivery service. Also in the case of realizing such a mechanism, similarly to the above, using a multimode wireless terminal that can be simultaneously connected to the base station 90 and the wireless LAN access point 91 of the cellular wireless network as a relay station, It is possible to relay and transmit the broadcast distribution message within the communication area between the LAN access point 91 and the cellular base station 90.

<5> Second Example According to this Embodiment In a service for distributing disaster occurrence information and the like to an unspecified number of wireless terminals based on an in-cell broadcast function such as the CBS function, a disaster map or evacuation information Or the like on the screen of the wireless terminal is considered to be relatively large distribution information of several hundred kilobytes or more. However, in a disaster information delivery service such as ETWS, a message that broadcasts disaster occurrence information to wireless terminals in a cell using the CBS function can only deliver data of a size of several tens of bytes. Therefore, it is impossible to broadcast-distribute to the wireless terminals in the cell by directly including the above-mentioned rich content information in the message directly in the message.

  In such a case, it is common to describe the URL or URI of a Web server or content providing server that stores the above-mentioned rich content information in a message broadcast-distributed within a communication area that is a distribution destination. Has been done. However, in this case, if the user of the wireless terminal that received the message distribution tries to access the Web server or content providing server based on the URL or URI included in the message, all users in the communication area that is the distribution destination Will simultaneously access the Web server and the content providing server. As a result, a congestion state may occur in the cellular wireless network, or a content provider server in which simultaneous access from a large number of wireless terminals located in the communication area of the message distribution destination may be overloaded. .

  Therefore, in the second example according to the present embodiment, when a message is broadcasted to a wireless terminal based on an in-communication area broadcast function (such as a CBS function) specific to a cellular wireless network or a wireless LAN, A mechanism for efficiently distributing large-capacity content information, which is related information accompanying a message, will be exemplified. That is, in the second embodiment, the large-capacity content information attached to the message broadcast-distributed to all terminals in the wireless LAN communication area is broadcast-distributed to all the terminals by the same method as the first embodiment. In this case, a mechanism for preventing access load and congestion on the wireless network side is disclosed. The large-capacity content information, which is related information attached to the message, may be multimedia content information or rich content information for supplementing the notification information content of the message. In order to realize the above-described mechanism, in the second embodiment, even if the above-described message is distributed from the cellular radio network based on the intra-cell broadcast function, the large-capacity content information attached to the message is transmitted to the Internet. To download from a wireless LAN rather than a cellular wireless network. This is because, in order to download large-capacity content from the Internet, not via a cellular wireless network, but via a wireless LAN that can achieve a larger communication bandwidth and higher communication speed than a cellular wireless network for batch downloading of large-capacity bulk data This is because congestion in the wireless network can be prevented when the large-capacity content is distributed to the wireless terminal. In the second embodiment, the following measures are taken in order to prevent concentration of access to the wireless network due to simultaneous access to large-capacity content from all wireless terminals in the communication area. . First, the multi-mode wireless terminal that relays the above-mentioned message determines whether or not it is necessary to access large-capacity content information as related information accompanying the above-described message. Then, the wireless LAN access point requested to access the large-capacity content information from the multi-mode wireless terminal is used as a proxy for all the wireless terminals located in the communication area. Is downloaded from the Internet and broadcast to all wireless terminals in the communication area.

  Specifically, first, using a multimode wireless terminal that is simultaneously connected to a base station of a cellular radio network and a wireless LAN access point as a relay station, the cellular base station of the message distribution source, the wireless LAN access point, Intra-cell broadcast delivery messages are relayed between At that time, if the message includes a URL or URI indicating the link to the provider of the large-capacity content information described above, the multimode wireless terminal relaying the message transmits the URL or URI via the URL or URI. Request the wireless LAN access point described above to download the large-capacity content. Upon receiving the request from the multimode wireless terminal, the wireless LAN access point downloads the large-capacity content into a cache memory in the local station and temporarily stores the large-capacity content in the multimode wireless terminal 10m. Forward. Finally, the wireless LAN access point broadcasts the temporarily stored large-capacity content information to all wireless terminals located within the communication area of the local station.

  In addition, when the delivery message described above is a message that is broadcasted by a disaster information delivery system such as ETWS based on the CBS function in the cellular radio network, the large-capacity content information described above is related to the delivery message described above. It is possible to use multimedia contents for displaying the disaster map and evacuation information on the screen of the wireless terminal.

  Hereinafter, the network connection shown in FIG. 5 will be described as a premise for explaining in detail the flow of the signal processing operation in the second embodiment. FIG. 5 shows a network in which the above-described large-capacity content is distributed from the content provider server 20 on the Internet to a wireless terminal via a plurality of different types of wireless access networks including a cellular wireless network and a wireless LAN network. It is a connection.

  The network connection configuration of FIG. 5 includes two core networks (CN: Core Network) connected to the wireless terminal 10, two wireless access networks 40A and 40B, and wireless access networks 40A and 40B via core network gateways 61 and 62. 51/52, an Internet network 80 connected to the core network 51/52 via an external connection gateway 71/72, and a server 20 connected to the Internet network 80. The server 20 is a content provider server that provides the above-described large-capacity content to an unspecified number of wireless terminals, and may be implemented as a Web server.

  The radio access networks 40A and 40B are networks that provide the radio terminal 10 with a radio access path to the core network via radio communication. The radio access network 40A can be a UMTS network, which is a third generation cellular radio network, or an LTE network, which is a fourth generation cellular radio network, and the radio access network 40B is an IEEE802.11a standard or an IEEE802.11g standard. A wireless LAN access network such as Wi-Fi based on the above.

  The core networks 51 and 52 are formed by connecting a number of router devices and network control server devices through high-speed lines within a wireless communication service provider, and connecting wireless terminals to the Internet (E-UTRAN core network). Corresponds to the P-GW (PDN-Gateway) function), terminal mobility management of the wireless terminal (corresponding to the MME function in the E-UTRAN core network), or communication service authentication of the wireless terminal (E-UTRAN) (Corresponding to the function of HSS in the core network). The core network 51 is a core network that forms a cellular wireless network, and can be wirelessly accessed from the wireless terminal 10 via the wireless access network 40A and the core network gateway 61. On the other hand, the core network 52 is wirelessly accessible from the wireless terminal 10 via the wireless access network 40B and the core network gateway 62. The core network 52 can be a mobile IP network that supports communication based on the TCP / IP protocol.

  The external connection gateway 71/72 connects the core network 51/52 to the Internet network 80, and the core network 51/52 can communicate traffic with the Internet network 80. When the core network 51 is configured based on the E-UTRAN standard, the external connection gateway 71 can be a P-GW (PDN-Gateway). The core network 52 can be a mobile network that functions as an IP protocol-based core network for a wireless LAN based on Mobile IP.

  In FIG. 5, a radio bearer 30A is radio connection means for connecting the radio terminal 10 to a radio access network 40A that is a cellular radio network. Similarly, the radio bearer 30B is a radio connection unit that connects the radio terminal 10 to the radio access network 40C that is a Wi-Fi network.

  In FIG. 5, the radio terminal 10 selectively uses one of the radio bearers 30 </ b> A or 30 </ b> B and wirelessly connects to either the radio access network 40 </ b> A or 40 </ b> B. Subsequently, the wireless terminal 10 performs end-to-end communication based on TCP / IP with the server 20 via the wireless access network, the core network 51/52, and the Internet network 80.

  Next, FIG. 6 shows the above-described series of radio signal flows executed between the cellular base station, the wireless LAN access point, and the multi-mode wireless terminal 10m in the second embodiment. FIG. 7 shows an event flow diagram for explaining the flow of signal processing operations among the cellular base station, the wireless LAN access point, and the multi-mode wireless terminal 10m. Hereinafter, the flow of a series of signal processing operations in the second embodiment will be described with reference to FIGS. 6 and 7. The cellular core 51 network shown in FIG. 6 integrally represents the radio access network 40A and the core network 51 shown in FIG. Similarly, the ISP network / mobile network 52 shown in FIG. 6 integrally represents the radio access network 40B and the mobile network 52 shown in FIG.

  In FIG. 6, the cellular base station 90 that has received a message to be distributed based on the CBS function from the cellular core network 51 constituting the cellular radio network broadcasts the message into a cell covered by the own station, and performs multimode. The wireless terminal 10m receives the broadcast message (step S1 in FIG. 7). In FIG. 6, the multi-mode wireless terminal 10m has two types of wireless interface circuits 102a and 102b (FIG. 2) that can be connected to both a base station 90 and a wireless LAN network access point 91 under the cellular wireless network. Equipped with.

  Subsequently, the multi-mode wireless terminal 10m that has received the delivery message described above determines whether or not the message includes a URL or URI indicating a link to the provider of the large-capacity content information described above (see FIG. 7 step S2). In this case, in order to indicate that the above-described provider link indicates a large-capacity content to be distributed to all wireless terminals in the communication area as a distribution destination together with the above-described distribution message, the top of the above-described URL or URI In the part, a character string “mediato: //” is described as a protocol identifier. For the same purpose as described above, it is possible to describe the unique protocol identifier “wlanto: //” newly defined in the present embodiment in the head part of the URL or URI described above. is there. If the provider link described above is included in the distribution message, the multimode wireless terminal 10m that has received the distribution message described above is a wireless LAN interface 102b (FIG. 2) is turned on (step S3 in FIG. 7). Thereafter, when the multimode wireless terminal 10m detects the beacon signal of the wireless LAN access point 91, the multimode wireless terminal 10m responds by returning a Probe Response frame to the received beacon signal. Thereby, an association for subsequent wireless traffic transmission is established between the multi-mode wireless terminal 10m and the wireless LAN access point 91 (step S4 in FIG. 7). Subsequently, the multi-mode wireless terminal 10m activates a dedicated application for downloading the large-capacity content information described above.

  The dedicated application activated on the multi-mode wireless terminal 10m requests the wireless LAN access point 91 described above to download the large-capacity content via the URL or URI (step S5 in FIG. 7). The wireless LAN access point 91 that has received the request from the multimode wireless terminal 10m connects to the content provider server 20 (FIG. 6) in the Internet 80 via the ISP network / mobile network 52 (FIG. 6) (FIG. 6). 7 step S6). Subsequently, the wireless LAN access point 91 downloads the large-capacity content from the content provider server 20 (step S6 in FIG. 7) and temporarily stores it in the cache memory in the wireless LAN access point 91 (FIG. 7). 7), the large-capacity content is transferred to the multimode wireless terminal 10m. Finally, the wireless LAN access point 91 broadcasts and distributes the large-capacity content information temporarily stored in the cache memory in the local station to the wireless terminal 10s located in the communication area of the local station. (Step S8 in FIG. 7).

  At this time, as shown in FIGS. 5 and 6, as a network connection path for downloading the large-capacity content information from the content provider server 20 in the Internet 80, the cellular base station 90, the cellular core network 51, and the Internet 80 are used. There is also a route through. However, unlike the wireless LAN network, the cellular wireless network constituted by the cellular base station 90 and the cellular core network 51 is often used for bulk data transmission such as downloading of large-capacity content information at a time. It is difficult to allocate bandwidth or temporarily achieve very high communication throughput. Therefore, in the second embodiment, the cellular base station 90 is prohibited from downloading the large-capacity content on the content provider server 20 from the multi-mode wireless terminal 10m via the cellular wireless network.

  In parallel with the above-described large-volume content information distribution operation, the multi-mode wireless terminal 10m transmits the above-described distribution message from the cellular base station 90 to the wireless LAN access / transmission by the same method as described in the first embodiment. Relay to point 91. Subsequently, the wireless LAN access point 91 broadcasts and distributes the relayed distribution message in the communication area of the local station. Note that the wireless LAN access point 91 in FIG. 3 is one or more neighboring wireless LAN access points located at a distance that allows wireless communication with good signal quality with the multi-mode wireless terminal 10m.

<6> Advantages of this Embodiment As described above, the first example described with reference to FIG. 3 is a multimode wireless terminal or cellular wireless network that is temporarily unable to connect to the cellular wireless network. The wireless terminal 10s having no connection means to the mobile station can receive an information distribution service based on an intra-cell broadcast function (such as a CBS function) provided only by the base station 90 of the cellular radio network. Similarly, the first embodiment can allow a cellular wireless terminal that does not have a wireless LAN interface circuit to receive a broadcast distribution service provided only at the access point 91 in the wireless LAN network. In addition, transmission / reception of information signals executed in each of the cellular base station 90, the wireless LAN access point 91, and the multimode wireless terminal 10m that relays the distribution message between them is all performed at the data link layer level (L2 level). Is executed. Therefore, according to the first embodiment, a message can be quickly distributed to all wireless terminals in a communication area as a distribution destination with a minimum protocol overhead. Further, in the second embodiment described with reference to FIG. 5, access to large-capacity content information is performed based on the broadcast distribution function for all the wireless terminals 10s located in the distribution area of the message information. When executing the above, it is possible to prevent access concentration from a large number of wireless terminals 10s to the wireless network and the content provider server 20 and communication priority conflicts from occurring.

  The present invention relates to a control program and an apparatus that constitute a system for broadcasting distribution information such as disaster occurrence information all at once to an unspecified number of wireless terminals located in a communication area of a wireless communication network. It is possible to use.

10 m Multi-mode wireless terminal 10 s Wireless terminal 20 Server for providing network service to wireless terminal 30 Radio bearer 40 Wireless access network 51 Core network 52 Core network 61 Core network gateway 62 Core network gateway 71 External connection gateway 72 External connection gateway 80 Internet Network 90 Cellular base station 91 Wireless LAN access point 101 Antenna 102 Wireless interface 103 Memory 104 Control processor 105 User input / output device 106 Storage 107 Bus

Claims (4)

A method for distributing a broadcast message distributed in a first wireless communication network to one or more wireless terminals connectable only to a second wireless communication network:
An access point in the second wireless communication network is connected to the first wireless communication network via a relay station capable of relaying a wireless signal from the first wireless communication network to the second wireless communication network. Receiving the broadcast message broadcast from the wireless communication network ;
Broadcasting the received broadcast message to the one or more wireless terminals by the access point; and
Receiving the broadcast message, the relay station converting the broadcast message into a format suitable for broadcast distribution in the second wireless communication network,
The relay station includes two connection means that can be connected to the first wireless communication network and the second wireless communication network, respectively, and the first wireless communication network and the second wireless communication network are connected to each other. A multi-mode wireless device that can be wirelessly connected to both sides of the communication network,
The converted format is a format in which the broadcast message is included in a frame related to an initial access of the relay station to the second wireless communication network. A first wireless connection unit connectable to the first wireless communication network;
A second wireless connection unit connectable to the second wireless communication network;
When the broadcast message distributed from the first wireless communication network is received via the first wireless connection unit, the second connection is possible via the second wireless connection unit. Requesting an access point in a wireless communication network to distribute the broadcast message to one or more wireless terminals located in the second wireless communication network; and A control unit configured to relay the broadcast message to the access point via a unit;
Equipped with,
The relayed to said access point broadcast message is delivered from the access point to another wireless terminal is capable of communicating with only the second wireless communication network,
The broadcast message is converted into a format suitable for broadcast distribution in the second wireless communication network in the control unit that has received the broadcast message,
The multi-mode wireless terminal , wherein the converted format is a format in which the broadcast message is included in a frame related to an initial access of the second wireless connection unit to the second wireless communication network . A method for distributing a broadcast message distributed in a first wireless communication network to one or more wireless terminals connectable only to a second wireless communication network:
An access point in the second wireless communication network is connected to the first wireless communication network via a relay station capable of relaying a wireless signal from the first wireless communication network to the second wireless communication network. Receiving the broadcast message broadcast from the wireless communication network ;
Broadcasting the received broadcast message to the one or more wireless terminals by the access point; and
Receiving the broadcast message, the relay station converting the broadcast message into a format suitable for broadcast distribution in the second wireless communication network,
The relay station includes two connection means that can be connected to the first wireless communication network and the second wireless communication network, respectively, and the first wireless communication network and the second wireless communication network are connected to each other. A multi-mode wireless device that can be wirelessly connected to both sides of the communication network,
The method in which the converted format is a format in which the broadcast message is included in the frame in which a bit indicating high urgency included in a header of the frame of the second wireless communication network is set to ON. A first wireless connection unit connectable to the first wireless communication network;
A second wireless connection unit connectable to the second wireless communication network;
When the broadcast message distributed from the first wireless communication network is received via the first wireless connection unit, the second connection is possible via the second wireless connection unit. Requesting an access point in a wireless communication network to distribute the broadcast message to one or more wireless terminals located in the second wireless communication network; and A control unit configured to relay the broadcast message to the access point via a unit;
Equipped with,
The relayed to said access point broadcast message is delivered from the access point to another wireless terminal is capable of communicating with only the second wireless communication network,
The broadcast message is converted into a format suitable for broadcast distribution in the second wireless communication network in the control unit that has received the broadcast message,
The converted format is a multi-mode radio that is a format in which the broadcast message is included in the frame in which a bit indicating high urgency included in a header of the frame of the second wireless communication network is set to ON. Terminal.

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