JP5291951B2 - Wireless terminal and wireless communication method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To execute a QoS-secured communication even when the QoS of a communication between a most significant radio terminal and a radio base station is not secured, in a tree-structure network constituted of a plurality of radio terminals. <P>SOLUTION: This radio terminal includes: a message receiving part 151 for receiving a security demand which demands a QoS security with the radio base station in a state being directly connected to the radio base station; a determining part 152 for determining whether or not the QoS is securable; an information processing part 153 for determining whether or not securable terminal information indicating that the radio terminal with a low priority in the tree-structure network is a securable terminal which can secure the QoS is added to the security demand, when it is determined that the QoS is not securable; and a message notifying part 156 for notifying a message instructing a direct connection with the radio base station and the QoS security to the securable terminal based on the securable terminal information, when it is determined that the securable terminal information is present. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a radio terminal constituting a tree-structured network having a radio terminal directly connected to a radio base station as a top level and a radio communication method used for the radio terminal.

  2. Description of the Related Art Conventionally, QoS guarantee, which is a technique for guaranteeing a predetermined QoS (called communication quality or service quality) in a communication system, is known. In the QoS guarantee, specific communication is prioritized over other communication, and a communication band is secured for the specific communication. QoS includes, for example, a communication band, delay time, jitter, or packet loss rate.

  Further, an ad hoc network that is a wireless network autonomously configured by a plurality of wireless terminals having a relay function is known. In such an ad hoc network, when a plurality of communication paths are formed between a data transmission source wireless terminal and a data transmission destination wireless terminal, a method of selecting a communication path that satisfies the required QoS has been proposed. (See Patent Document 1).

Furthermore, a method has been proposed in which wireless terminals constituting an ad hoc network communicate with a wireless base station on the infrastructure network side (see Patent Document 2). In this case, a tree structure network having a wireless terminal directly connected to the wireless base station as the highest rank is configured by a plurality of wireless terminals. One wireless terminal that constitutes such a tree-structured network can communicate with a wireless base station via another wireless terminal even if the wireless terminal is outside the radio wave coverage of the wireless base station.
Japanese Patent No. 3755881 (paragraph [0033], FIG. 5) Japanese Patent Laid-Open No. 2003-124876 (page 6-7, FIG. 7)

  When communication with a guaranteed QoS is performed with a wireless base station in the wireless terminals constituting the above-described tree structure network, there are the following problems. Specifically, the highest-level wireless terminal that is directly connected to the wireless base station in the tree-structured network cannot always execute communication with guaranteed QoS with the wireless base station. For example, the highest radio terminal may not support QoS guarantee or may fail to establish QoS guarantee with a radio base station even if it supports QoS guarantee.

  In a tree structure network, wireless terminals other than the highest wireless terminal communicate with the wireless base station via the highest wireless terminal. Therefore, when QoS of communication between the highest wireless terminal and the wireless base station is not guaranteed. However, there is a problem that communication with guaranteed QoS cannot be performed even in wireless terminals other than the highest-level wireless terminal.

  Therefore, the present invention has been made to solve the above-described problem, and in a tree-structured network composed of a plurality of wireless terminals, QoS of communication between the highest wireless terminal and the wireless base station is not guaranteed. Even in such a case, it is an object to provide a wireless terminal and a wireless communication method capable of performing communication with a guaranteed QoS with a wireless base station.

In order to solve the above-described problems, the present invention has the following features. First, the first feature of the present invention is a wireless terminal constituting a tree-structured network having a wireless terminal directly connected to a wireless base station as a top layer, a direct connection unit directly connected to the wireless base station, Guarantee requesting a guarantee of communication quality, which is a quality of communication with the radio base station, from a radio terminal located in a lower position in the tree structure network in a state where the direct connection unit is directly connected to the radio base station A request receiving unit that receives a request, and a terminal capable of guaranteeing the communication quality added to the guarantee request if the communication quality cannot be guaranteed when the request receiving unit receives the guarantee request The gist of the present invention is to include an instruction notifying unit for notifying the guaranteeable terminal of the direct connection instruction to the radio base station and the instruction of guaranteeing the communication quality based on the information .

  According to such a wireless terminal, the highest-order wireless terminal directly connected to the wireless base station in the tree-structured network receives a guarantee request from the wireless terminal located at a lower position, and the own wireless terminal is connected to the wireless base station. If communication quality cannot be guaranteed, direct connection with the radio base station and communication quality assurance instructions can be guaranteed based on the guaranteeable terminal information that is added to the guarantee request and indicates the guaranteeable terminal located at the lower level. Send to the terminal. As a result, the communication quality with the radio base station is guaranteed by the guaranteeable terminal, so the wireless terminal that is the source of the guarantee request performs communication with the radio base station via the guaranteeable terminal. can do.

  A second feature of the present invention relates to the first feature of the present invention, wherein the instruction notifying unit determines that the guaranteeable terminal information is not added to the guarantee request by the information judging unit, The gist is to notify the wireless terminal (for example, wireless terminal MS4) that has transmitted the guarantee request that the communication quality cannot be guaranteed (QoS guarantee result notification message).

  A third feature of the present invention relates to the first feature of the present invention, wherein the instruction notification unit determines that the guaranteeable terminal information is added to the guarantee request by the information judgment unit, It is determined whether there are a plurality of guaranteeable terminals, and when it is determined that there are a plurality of guaranteeable terminals, a guaranteeable terminal to which the instruction is notified is selected from the plurality of guaranteeable terminals The gist is to do.

  A fourth feature of the present invention relates to the third feature of the present invention, wherein the guarantee request indicates a reception strength of a radio signal received from the radio base station by a radio terminal located in a lower position in the tree-structured network. Including the reception strength information, the instruction notifying unit can guarantee the highest reception strength among the plurality of guaranteeable terminals based on the reception strength information when it is determined that there are a plurality of guaranteeable terminals. The gist is to select a terminal as a guaranteeable terminal of the notification destination.

  A fifth feature of the present invention relates to the third feature of the present invention, wherein the guarantee request is a communication resource (for example, a wireless terminal located at a lower position in the tree-structured network that can be used for communication in the ad hoc network) Resource remaining information indicating the remaining amount of communication band), and when the instruction notifying unit determines that there are a plurality of guaranteeable terminals, the instruction notifying unit determines a plurality of guaranteeable terminals based on the resource remaining amount information. The gist is to select the guaranteeable terminal having the largest remaining amount of the communication resource as the guaranteeable terminal of the notification destination.

  A sixth feature of the present invention relates to the third feature of the present invention, wherein the guarantee request is the number of routed terminals indicating the number of routed terminals that is the number of wireless terminals that relayed the guarantee request in the tree-structured network. The instruction notifying unit, when it is determined that there are a plurality of guaranteeable terminals, the wireless terminal that is the transmission source of the guarantee request from the plurality of guaranteeable terminals based on the number of via terminal information The gist is to select the guaranteeable terminal having the smallest number of via terminals from the terminal as the guaranteeable terminal of the notification destination.

  A seventh feature of the present invention relates to the first feature of the present invention, wherein the guarantee request is a communication resource that can be used for communication in the tree-structured network by a wireless terminal located in a lower position in the tree-structured network. Resource remaining information indicating a remaining amount, and when the information determining unit determines that the guaranteeable terminal information is added to the guarantee request by the information determining unit, based on the resource remaining amount information, In the tree-structured network, it is determined whether all the wireless terminals on the route from the wireless terminal that is the source of the guarantee request to the guaranteeable terminal have a certain remaining resource amount, and all the wireless terminals When it is determined that the terminal does not have a certain amount of remaining resources, the wireless terminal that is the source of the guarantee request is notified that the communication quality cannot be guaranteed. The the gist.

An eighth feature of the present invention is a wireless terminal constituting a tree-structured network having a wireless terminal directly connected to a wireless base station as a top layer, a direct connection unit directly connecting to the wireless base station, and the direct connection In a state where the connection unit is not directly connected to the radio base station, a guarantee request is issued to request a guarantee of communication quality, which is a quality of communication with the radio base station, from a radio terminal located in a lower position in the tree-structured network. A request receiving unit that receives the guarantee request, a guarantee request relay unit that relays the guarantee request received by the request receiving unit to a wireless terminal located at a higher level in the tree-structured network, and the request receiving unit receives the guarantee request In addition, if the communication quality with the radio base station can be guaranteed, the communication quality can be guaranteed for the guarantee request relayed by the guarantee request relay unit. Comprising an information adding unit for adding to guarantee possible terminal information, and the guarantee request relay unit gist to relay the assurance capable terminal information is added the guarantee request to the radio terminal located in said upper And

  A ninth feature of the present invention relates to the eighth feature of the present invention, wherein a direct connection instruction (base station connection instruction message) with the wireless base station is received from a wireless terminal located at a higher level in the tree-structured network. An instruction receiving unit (message receiving unit 151) that receives the communication quality guarantee instruction (base station connection instruction message), and the direct connection unit, when the instruction receiving unit receives the instruction, The gist is to directly connect to the radio base station and to request the radio base station to guarantee the communication quality.

  A tenth feature of the present invention relates to the eighth feature of the present invention, and is a reception strength information acquisition unit (information acquisition unit 154) that acquires reception strength information indicating a reception strength of a radio signal received from the radio base station. The information adding unit adds the reception strength information acquired by the reception strength information acquiring unit to the guarantee request relayed by the guarantee request relay unit.

  An eleventh feature of the present invention relates to the eighth feature of the present invention, and is a resource for acquiring resource remaining amount information indicating a remaining amount of communication resources (for example, communication band) that can be used for communication in the tree-structured network. The information addition unit further includes a remaining amount information acquisition unit (information acquisition unit 154), and the information addition unit responds to the guarantee request relayed by the guarantee request relay unit, the resource remaining information acquired by the resource remaining amount information acquisition unit. The gist is to add quantity information.

  A twelfth feature of the present invention relates to the eighth feature of the present invention, wherein the guarantee request is the number of routed terminals indicating the number of routed terminals that is the number of wireless terminals that relayed the guarantee request in the tree-structured network. The information adding unit adds the route terminal number information obtained by adding 1 to the number of routed terminals to the guarantee request relayed by the guarantee request relay unit.

A thirteenth feature of the present invention is a wireless communication method used for a wireless terminal constituting a tree-structured network having a wireless terminal directly connected to a wireless base station as a top level, and is directly connected to the wireless base station. A guarantee request for requesting a guarantee of communication quality, which is a quality of communication with the radio base station, from a radio terminal located in a lower position in the tree-structured network, and the guarantee in the receiving step When the request is received, if the communication quality can not be guaranteed, based on the guaranteeable terminal information that can guarantee the communication quality added to the guarantee request, the guaranteeable terminal and the radio base station Providing a direct connection instruction and a communication quality guarantee instruction.

A fourteenth feature of the present invention is a wireless communication method used for a wireless terminal constituting a tree-structured network having a wireless terminal directly connected to a wireless base station as a top level, and is directly connected to the wireless base station. In a state where no guarantee is received, a guarantee request for requesting guarantee of communication quality, which is a quality of communication with the radio base station, is received from a radio terminal located in a lower position in the tree-structured network, and the guarantee is received in the receiving step Adding guaranteeable terminal information indicating that the communication quality can be guaranteed to the guarantee request when the communication quality with the radio base station can be guaranteed when the request is received; a step of relaying the assurance capable terminal information is added the guarantee request to the wireless terminal located in the upper of the said tree network, the The gist be obtained.

  According to the present invention, in a tree structure network composed of a plurality of wireless terminals, even when QoS of communication between the highest-level wireless terminal and the wireless base station is not guaranteed, communication with guaranteed QoS is executed with the wireless base station. A wireless terminal and a wireless communication method can be provided.

  Next, a first embodiment and a second embodiment of the present invention will be described with reference to the drawings. In the following description of the drawings in the first embodiment and the second embodiment, the same or similar parts are denoted by the same or similar reference numerals.

[First Embodiment]
In the following first embodiment, (1) the overall schematic configuration of the radio communication system, (2) the configuration of the radio terminal, (3) the overall operation of the radio communication system, (4) the detailed operation of the radio terminal, (5) action・ Explain the effect.

(1) Overall Schematic Configuration of Radio Communication System FIG. 1 is an overall schematic configuration diagram of a radio communication system 1A according to the first embodiment. As shown in FIG. 1, the radio communication system 1A includes a radio base station BS and radio terminals MS1 to MS6. The radio base station BS is connected to a wide area network (WAN) not shown. Hereinafter, the radio base stations BS and WAN are appropriately referred to as “infrastructure network”.

  Each of the radio terminals MS1 to MS6 has a function of directly communicating with the radio base station BS and a function of relaying communication between the radio base station BS and other radio terminals. That is, each of the radio terminals MS1 to MS6 performs direct communication (single-hop communication) with the radio base station BS or indirect communication (multi-hop communication) with the radio base station BS via at least one other radio terminal. be able to.

  The radio base station BS constitutes a service area SA (radio wave arrival area), which is an area that can directly communicate with the radio terminals MS1 to MS6. In the example of FIG. 1, the radio terminal MS1 is located in the service area SA, and is directly connected to the radio base station BS and directly communicates with the radio base station BS. Here, direct connection is a state in which a wireless communication channel is set with the wireless base station BS, and direct communication is a state in which user data is transmitted and received through the set wireless communication channel. It is. The radio terminal MS2 is also located in the service area SA, and can directly connect to and communicate with the radio base station BS.

  In the first embodiment, an ad hoc network AH that is an autonomous wireless network is formed by the wireless terminals MS1 to MS6. The ad hoc network AH has a tree structure in which the radio terminal MS1 directly connected to the radio base station BS is the highest layer (root node).

  In the example of FIG. 1, the radio terminal MS2 is indirectly connected to the radio base station BS via the radio terminal MS1. Similarly, the radio terminal MS3 is indirectly connected to the radio base station BS via the radio terminal MS1 and the radio terminal MS2. Thereby, the radio terminal MS3 can communicate with the radio base station BS via the radio terminal MS1 and the radio terminal MS2 even outside the service area SA. In such a tree-structured ad hoc network AH, the radio terminal MS5 and the radio terminal MS6 are located in the lowest hierarchy (leaf node).

  Each of the radio terminals MS1 to MS6 stores a radio terminal belonging to the hierarchy immediately above itself as a master, and stores a radio terminal belonging to the hierarchy immediately below itself as a slave. For example, the radio terminal MS2 shown in FIG. 1 stores the radio terminal MS1 as a master and stores the radio terminal MS3 as a slave.

  In the first embodiment, the radio terminal MS4 located outside the service area SA connects to the radio base station BS via the radio terminals MS1 to MS3, and starts communication with which the QoS with the radio base station BS is guaranteed. Is required. Here, communication requiring QoS guarantee includes an application with high real-time characteristics (for example, VoIP).

  The radio terminal MS4 transfers a QoS guarantee request message for requesting guarantee of communication quality with the radio base station BS to the radio terminal MS1 via the radio terminal MS2 and the radio terminal MS3. Here, it is assumed that the wireless terminal MS2 and the wireless terminal MS3 support QoS guarantee in the ad hoc network AH and can secure a communication band for the wireless terminal MS4.

  The radio terminal MS1 receives the QoS guarantee request message from the radio terminal MS4. However, if the radio terminal MS1 does not support the QoS guarantee with the radio base station BS or if it fails to establish the QoS guarantee with the radio base station BS even if it supports the QoS guarantee, the radio terminal MS1 QoS of communication with the radio base station BS is not guaranteed, and the radio terminal MS4 cannot perform communication with the QoS guaranteed with the radio base station BS. In the first embodiment, a case will be described in which the radio terminal MS1 does not support QoS guarantee with the radio base station BS.

  Since the radio terminals MS1 to MS6 have the same configuration, each of the radio terminals MS1 to MS6 is appropriately referred to as a radio terminal MS in the following description.

(2) Configuration of Radio Terminal Next, the configuration of the radio terminal MS, specifically (2.1) the schematic configuration of the radio terminal and (2.2) the detailed configuration of the radio terminal will be described.

(2.1) Schematic Configuration of Radio Terminal FIG. 2 is a schematic configuration diagram of the radio terminal MS. As illustrated in FIG. 2, the radio terminal MS includes a base station communication transceiver 130, an ad hoc communication transceiver 140, a controller 150, an input unit 160, an output unit 170, and a storage unit 180.

  The base station communication transmitting / receiving unit 130 is connected to the radio base station BS and performs direct communication with the radio base station BS. The base station communication transceiver 130 has a configuration conforming to, for example, cdma 2000 nx evolution-data only (EV-DO), which is a kind of third-generation mobile phone system. The base station communication transmitting / receiving unit 130 transmits / receives a radio signal (RF signal) according to, for example, a CDMA system to / from the radio base station BS.

  As an example, the base station communication transmission / reception unit 130 is a Rev. 1 that is a kind of EV-DO. 0 or Rev. It has a configuration based on 0. Rev. 0 is a method that does not support QoS guarantee with the radio base station BS. A is a method corresponding to QoS guarantee with the radio base station BS. In the first embodiment, the base station communication transmitting / receiving unit 130 constitutes a direct connection unit that directly connects to the radio base station BS.

  The ad hoc communication transmitting / receiving unit 140 is connected to a wireless terminal located directly above or directly below the tree-structured ad hoc network AH, and communicates with the wireless base station BS via the wireless terminal located directly above. The ad hoc communication transmission / reception unit 140 has a configuration conforming to, for example, a wireless LAN (IEEE802.11 or the like) or Bluetooth (registered trademark). The ad hoc communication transmission / reception unit 140 performs conversion between a radio signal and a baseband signal, and transmits / receives the baseband signal to / from the control unit 150. In the first embodiment, the ad hoc communication transceiver 140 has a QoS guarantee function within the ad hoc network AH, that is, a QoS guarantee function between wireless terminals.

  The input unit 160 includes a key input unit that inputs user operation details, a microphone that converts a user's voice into an electrical signal, and the like. The output unit 170 includes a display unit that displays images and operation details (input telephone number, address, and the like), a speaker that converts an electrical signal into sound, and outputs the sound.

  The control unit 150 is configured by a CPU, for example, and controls various functions provided in the wireless terminal MS. The storage unit 180 stores various information used for control and the like in the wireless terminal MS. The storage unit 180 includes a master / slave storage unit 181 that stores and manages identification information for identifying a master and identification information for identifying a slave. As such identification information, a terminal ID or an address (IP address or MAC address) can be used.

(2.2) Detailed Configuration of Wireless Terminal Next, a detailed configuration of the wireless terminal MS, specifically, a main functional block configuration of each function executed by the control unit 150 will be described. FIG. 3 is a functional block configuration diagram of the radio terminal MS.

  As illustrated in FIG. 3, the wireless terminal MS includes a message reception unit 151, a determination unit 152, an information processing unit 153, a message relay unit 155, and a message notification unit 156. The message reception unit 151, the determination unit 152, the information processing unit 153, the message relay unit 155, and the message notification unit 156 are (a) when the base station communication transmitting / receiving unit 130 is not directly connected to the radio base station BS, The processing contents are different when the base station communication transmitting / receiving unit 130 is directly connected to the radio base station BS.

(A) When the base station communication transceiver 130 is not directly connected to the radio base station BS:
First, processing contents when the base station communication transmitting / receiving unit 130 is not directly connected to the radio base station BS, that is, processing other than the highest radio terminal MS will be described.

  The message receiving unit 151 receives the above QoS guarantee request message from the slave. That is, the message receiving unit 151 constitutes a request receiving unit that receives a QoS guarantee request.

  When the message reception unit 151 receives the QoS guarantee request message, the determination unit 152 determines whether or not QoS guarantee with the radio base station BS is possible. For example, the base station communication transmitting / receiving unit 130 may execute Rev. In the case of the configuration conforming to A, QoS guarantee with the radio base station BS is possible, and the base station communication transmitting / receiving unit 130 performs the Rev. described above. In the case of a configuration conforming to 0, QoS guarantee with the radio base station BS is impossible. In this way, the determination unit 152 constitutes a guarantee determination unit that determines whether or not QoS guarantee with the radio base station BS is possible.

  Further, when the message reception unit 151 receives the QoS guarantee request message, the determination unit 152 determines whether or not it can be directly connected to the radio base station BS. For example, the determination unit 152 determines that it can be directly connected to the radio base station BS when it can receive a radio signal from the radio base station BS with a reception sensitivity of a certain level or higher. The determination result by the determination unit 152 is notified to the information processing unit 153.

  When the determination unit 152 determines that the wireless base station BS can be directly connected and the QoS guarantee with the radio base station BS is possible, the information processing unit 153 can guarantee the QoS with the radio base station BS. Is added to the QoS guarantee request message. That is, the information processing unit 153 configures an information adding unit that adds the guaranteeable terminal information to the QoS guarantee request.

  The message relay unit 155 refers to the master / slave storage unit 181 and relays the QoS guarantee request message to the master. Thus, the message relay unit 155 constitutes a guarantee request relay unit that relays the QoS guarantee request to the master.

(B) When the base station communication transceiver 130 is directly connected to the radio base station BS:
Next, processing contents in the case where the base station communication transceiver 130 is directly connected to the radio base station BS, that is, the processing contents in the highest radio terminal MS will be described.

  When the message reception unit 151 receives the QoS guarantee request message, the determination unit 152 determines whether or not QoS guarantee with the radio base station BS is possible. For example, the determination unit 152 determines whether the QoS guarantee with the radio base station BS is supported. Alternatively, even when the determination unit 152 supports the QoS guarantee with the radio base station BS, the QoS guarantee with the radio base station BS is rejected when the QoS guarantee requested to the radio base station BS is rejected. Is determined to be impossible.

  If it is determined that QoS guarantee with the radio base station BS is not possible, the information processing unit 153 determines whether or not guaranteeable terminal information is added to the QoS guarantee request message received by the message receiving unit 151. . In other words, the information processing unit 153 configures an information determination unit that determines whether or not guaranteeable terminal information is added to the guarantee request.

  When it is determined that the guaranteeable terminal information is added to the QoS guarantee request message, the message notification unit 156 lowers the wireless terminal MS that can guarantee the QoS with the wireless base station BS based on the guaranteeable terminal information. The wireless terminal MS is identified. The message notification unit 156 transmits a base station connection instruction message instructing direct connection with the radio base station BS and QoS guarantee with the radio base station BS to the specified radio terminal MS.

  On the other hand, if no guaranteeable terminal information is added to the QoS guarantee request message, the message notification unit 156 cannot guarantee the QoS with the radio base station BS for the radio terminal MS that has transmitted the QoS guarantee request message. A QoS guarantee result notification message to that effect is notified.

(3) Overall Operation of Wireless Communication System Next, referring to FIG. 1, the overall operation of the wireless communication system 1A, specifically, (3.1) Operation pattern 1 of the wireless communication system, (3.2) Operation pattern 2 of the wireless communication system will be described.

(3.1) Operation pattern 1 of wireless communication system
FIG. 4 is a sequence diagram showing an operation pattern 1 of the wireless communication system 1A.

  In step S100, the radio terminal MS4 shown in FIG. 1 accepts a communication start request with guaranteed QoS from the user of the radio terminal MS4. In step S101, the radio terminal MS4 transmits a QoS guarantee request message to the radio terminal MS3.

  In step S102, the radio terminal MS3 relays the QoS guarantee request message received from the radio terminal MS4 to the radio terminal MS2. Here, since the radio terminal MS3 cannot directly connect to the radio base station BS, no guaranteeable terminal information is added to the QoS guarantee request message relayed to the radio terminal MS2.

  In step S103, the radio terminal MS2 relays the QoS guarantee request message received from the radio terminal MS3 to the radio terminal MS1. Here, it is assumed that the radio terminal MS2 can be directly connected to the radio base station BS and is compatible with QoS guarantee. Therefore, the radio terminal MS2 adds guaranteeable terminal information to the QoS guarantee request message relayed to the radio terminal MS1.

  The radio terminal MS1 that has received the QoS guarantee request message from the radio terminal MS2 does not support QoS guarantee with the radio base station BS, and therefore determines whether or not guaranteeable terminal information is added to the QoS guarantee request message. .

  Here, since the guaranteeable terminal information indicating the wireless terminal MS2 is added to the QoS guarantee request message, the wireless terminal MS1 transmits a base station connection instruction message with the wireless terminal MS2 as a transmission destination in step S104.

  In step S105, the radio terminal MS2 that has received the base station connection instruction message disconnects from the radio terminal MS1. In step S106, the radio terminal MS2 transmits a connection request to the radio base station BS and directly connects to the radio base station BS.

  Further, when the radio terminal MS2 is directly connected to the radio base station BS, the radio terminal MS2 requests the radio base station BS for QoS guarantee and establishes QoS guarantee with the radio base station BS (step S107). Note that the process of step S105 may be executed between step S106 and step S107 or after step S107.

  In step S108, the radio terminal MS2 transmits a QoS guarantee result notification message indicating that the QoS guarantee with the radio base station BS is established to the radio terminal MS3. In step S109, the radio terminal MS3 relays the QoS guarantee result notification message received from the radio terminal MS2 to the radio terminal MS4.

  Thereby, the wireless terminal MS4 desiring communication with guaranteed QoS communicates with the wireless base station BS via the wireless terminal MS3 and the wireless terminal MS2, and the communication with guaranteed QoS is performed with the wireless base station BS (infrastructure network). And become executable.

(3.2) Operation pattern 2 of wireless communication system
FIG. 5 is a sequence diagram showing an operation pattern 2 of the wireless communication system 1A. In addition, the description which overlaps with the operation pattern 1 mentioned above is abbreviate | omitted.

  In step S200, the radio terminal MS4 receives a communication start request with guaranteed QoS from the user of the radio terminal MS4. In step S201, the radio terminal MS4 transmits a QoS guarantee request message to the radio terminal MS3. In step S202, the radio terminal MS3 relays the QoS guarantee request message received from the radio terminal MS4 to the radio terminal MS2.

  In step S203, the radio terminal MS2 relays the QoS guarantee request message received from the radio terminal MS3 to the radio terminal MS1. Here, it is assumed that the radio terminal MS2 can directly connect to the radio base station BS, but does not support QoS guarantee. For this reason, guaranteeable terminal information is not added to the QoS guarantee request message relayed to the radio terminal MS1.

  The radio terminal MS1 that has received the QoS guarantee request message from the radio terminal MS2 does not support QoS guarantee with the radio base station BS, and therefore determines whether or not guaranteeable terminal information is added to the QoS guarantee request message. . Here, since guaranteeable terminal information is not added to the QoS guarantee request message, in step S204, the wireless terminal MS1 sends a QoS guarantee result notification message to the wireless terminal MS2 indicating that QoS with the wireless base station BS is not guaranteed. Send.

  In step S205, the radio terminal MS2 relays the QoS guarantee result notification message (QoS guarantee NG) to the radio terminal MS3. In step S206, the radio terminal MS3 relays the QoS guarantee result notification message (QoS guarantee NG) to the radio terminal MS4.

  As described above, in the operation pattern 2, the radio terminal MS4 cannot execute communication with guaranteed QoS with the radio base station BS (infrastructure network).

(4) Detailed operation of wireless terminal Next, detailed operation of the wireless terminal MS, specifically (4.1) QoS guarantee request message reception operation, (4.2) Base station connection instruction message reception operation, ( 4.3) The reception operation of the QoS guarantee result notification message will be described.

(4.1) QoS Guarantee Request Message Receiving Operation FIG. 6 is a flowchart showing a QoS guarantee request message receiving operation in the radio terminal MS.

  In step S301, the message receiving unit 151 determines whether a QoS guarantee request message has been received from the slave. If the QoS guarantee request message is received, the process proceeds to step S302. If not received, the process proceeds to step S315.

  In step S302, the determination unit 152 determines whether or not the own wireless terminal MS is within the range of the wireless base station BS. If the own radio terminal MS is within the range of the radio base station BS, the process proceeds to step S303. If the own radio terminal MS is out of the range, the process proceeds to step S308. In step S308, the message relay unit 155 transfers the QoS guarantee request message to the master.

  In step S303, the determination unit 152 determines whether the base station communication transceiver 130 is directly connected to the radio base station BS. If the base station communication transceiver 130 is not directly connected to the radio base station BS, the process proceeds to step S309.

  In step S309, the determination unit 152 determines whether the base station communication transceiver 130 is compatible with QoS guarantee with the radio base station BS. If the base station communication transmitting / receiving unit 130 is compatible with QoS guarantee with the radio base station BS, the process proceeds to step S310. If the base station communication transceiver 130 is not compatible with QoS guarantee, the process proceeds to step S311.

  In step S310, the information processing unit 153 adds the guaranteeable terminal information to the QoS guarantee request message. In step S311, the message relay unit 155 transfers the QoS guarantee request message to the master.

  On the other hand, when it is determined in step S303 that the base station communication transceiver 130 is directly connected to the radio base station BS, the process proceeds to step S304.

  In step S304, the determination unit 152 determines whether or not the base station communication transceiver 130 is compatible with QoS guarantee with the radio base station BS. If the base station communication transceiver 130 is compatible with QoS guarantee with the radio base station BS, the process proceeds to step S305. If not, the process proceeds to step S312.

  In step S305, the base station communication transceiver 130 requests the radio base station BS to guarantee QoS from the radio terminal MS.

  In step S306, the determination unit 152 determines whether or not QoS guarantee with the radio base station BS is established. If the QoS guarantee with the radio base station BS is established, the process proceeds to step S307. If the QoS guarantee with the radio base station BS is not established, the process proceeds to step S312.

  In step S307, the message notification unit 156 notifies the wireless terminal that has transmitted the QoS guarantee request message of a QoS guarantee result notification message indicating that the QoS guarantee with the radio base station BS has been established.

  In step S312, the information processing unit 153 determines whether or not guaranteeable terminal information is added to the QoS guarantee request message received by the message receiving unit 151. If guaranteeable terminal information is added to the QoS guarantee request message, the process proceeds to step S313. If not, the process proceeds to step S314.

  In step S313, the message notification unit 156 identifies a radio terminal MS (guaranteable terminal) capable of QoS guarantee with the radio base station BS based on the assured terminal information, and the base station for the identified radio terminal MS Send a connection instruction message. Here, the base station connection instruction message is a message instructing direct connection with the radio base station BS, QoS guarantee with the radio base station BS, and disconnection from the master.

  In step S314, the message notification unit 156 notifies the wireless terminal MS that has transmitted the QoS guarantee request message of a QoS guarantee result notification message that the QoS guarantee with the radio base station BS is not possible.

  On the other hand, if it is determined in step S301 that the QoS guarantee request message has not been received, the process proceeds to step S315. In step S315, the message reception unit 151 determines whether a base station connection instruction message has been received from the master. If a base station connection instruction message has been received, the process proceeds to step S401 (see FIG. 7). If not received, the process proceeds to step S316.

  In step S316, the message reception unit 151 determines whether a QoS guarantee result notification message has been received from the master. When the QoS guarantee result notification message is received, the process proceeds to step S501 (see FIG. 8).

(4.2) Receiving Operation of Base Station Connection Instruction Message FIG. 7 is a flowchart showing the receiving operation of the base station connection instruction message.

  In step S401, the message receiving unit 151 determines whether the base station connection instruction message is addressed to itself. If the base station connection instruction message is addressed to the own radio terminal MS, the process proceeds to step S402. If the base station connection instruction message is not addressed to the own radio terminal MS, the process proceeds to step S408. In step S408, the message relay unit 155 transfers the base station connection instruction message received by the message receiving unit 151 to the slave.

  In step S402, the base station communication transceiver 130 requests direct connection to the radio base station BS.

  In step S403, the base station communication transceiver 130 determines whether or not the direct connection to the radio base station BS is successful. If the direct connection to the radio base station BS has succeeded, the process proceeds to step S404. If the connection has failed, the process proceeds to step S409. In step S409, the message notification unit 156 notifies the wireless terminal that is the source of the QoS guarantee request message of a QoS guarantee result notification message indicating that QoS guarantee with the radio base station BS is impossible.

  In step S404, the base station communication transmitter / receiver 130 requests QoS guarantee from the radio base station BS. In step S405, the base station communication transceiver 130 determines whether or not QoS guarantee with the radio base station BS is successful. If the QoS guarantee with the radio base station BS has succeeded, the process proceeds to step S406. If the QoS guarantee has failed, the process proceeds to step S409.

  In step S406, the ad hoc communication transmitting / receiving unit 140 disconnects the connection with the master. In step S407, the message notification unit 156 notifies the wireless terminal MS that has transmitted the QoS guarantee request message of a QoS guarantee result notification message indicating that the QoS guarantee with the radio base station BS is successful.

(4.3) Receiving Operation of QoS Assurance Result Notification Message FIG. 8 is a flowchart showing the receiving operation of the QoS guarantee result notification message.

  In step S501, the message reception unit 151 determines whether or not the QoS guarantee result notification message is addressed to the own wireless terminal MS. If the QoS guarantee result notification message is addressed to the own radio terminal MS, the process proceeds to step S502. If not, the process proceeds to step S504. In step S504, the message relay unit 155 transfers the QoS guarantee result notification message received by the message receiving unit 151 to the slave.

  In step S502, the determination unit 152 determines whether or not the QoS guarantee result notification message indicates that the QoS guarantee with the radio base station BS is successful. When the QoS guarantee result notification message indicates that the QoS guarantee with the radio base station BS is successful, in step S503, the ad hoc communication transmitting / receiving unit 140 starts communication with the radio base station BS in which QoS is guaranteed.

(5) Operation / Effect According to the first embodiment, when the radio terminal MS2 not directly connected to the radio base station BS receives the QoS guarantee request message, is it possible to guarantee the QoS with the radio base station BS? Determine whether or not. If it is determined that QoS with the radio base station BS can be guaranteed, the radio terminal MS2 adds the guaranteeable terminal information to the QoS guarantee request message.

  Further, when the wireless terminal MS1 directly connected to the wireless base station BS receives the QoS guarantee request message, the wireless terminal MS1 determines whether the QoS guarantee with the wireless base station BS is possible, and determines that it is not possible. In this case, it is determined whether or not guaranteeable terminal information is added to the guarantee request. When the guaranteeable terminal information is added, the wireless terminal MS1 notifies the base station connection instruction message to the wireless terminal MS2 that can guarantee the QoS with the wireless base station BS based on the guaranteeable terminal information.

  When receiving the base station connection instruction message from the radio terminal MS1, the radio terminal MS2 directly connects to the radio base station BS and requests the QoS guarantee from the radio base station BS.

  Therefore, even when the QoS of communication between the radio terminal MS1 directly connected to the radio base station BS and the radio base station BS is not guaranteed, the QoS guarantee with the radio base station BS is established by the radio terminal MS2 that can guarantee QoS. Therefore, the radio terminal MS4 that desires communication with guaranteed QoS can execute communication with guaranteed QoS with the radio base station BS.

[Second Embodiment]
In the first embodiment described above, there is one wireless terminal that is a notification destination candidate of the base station connection instruction message notified by the message notification unit 156. On the other hand, in the second embodiment, a configuration will be described in which the notification destination of the base station connection instruction message can be selected when there are a plurality of wireless terminals that are candidates for the notification destination of the base station connection instruction message.

  In the following second embodiment, (1) the configuration of the radio terminal, (2) the configuration example of the message, (3) the operation of the radio terminal, (4) the specific example of the operation of the radio communication system, (5) the action / effect Will be described. In the second embodiment, points different from the first embodiment will be mainly described, and overlapping descriptions will be omitted.

(1) Configuration of Radio Terminal First, a detailed configuration of the radio terminal MS according to the second embodiment, specifically, a main functional block configuration of each function executed by the control unit 150 will be described. FIG. 9 is a functional block configuration diagram of the radio terminal MS according to the second embodiment.

  As illustrated in FIG. 9, the radio terminal MS according to the second embodiment includes an information acquisition unit 154 that acquires various types of information to be described later when the base station communication transceiver 130 is not directly connected to the radio base station BS. Have

  Specifically, the information acquisition unit 154 acquires reception intensity information indicating the reception intensity of the radio signal received by the base station communication transceiver 130 from the radio base station BS. Here, the received intensity information is not limited to the received radio wave intensity (RSSI) but may be a signal-to-noise ratio (SNR) or the like, but in the second embodiment, the received radio wave intensity is used. The information processing unit 153 adds the reception strength information acquired by the information acquisition unit 154 to the relayed QoS guarantee request message.

  Further, the information acquisition unit 154 acquires resource remaining amount information indicating the remaining amount of communication resources that can be used by the ad hoc communication transmitting / receiving unit 140 for communication within the ad hoc network AH. In the following, an example in which the remaining amount of communication band in the ad hoc communication transmitting / receiving unit 140 is used as the remaining amount of communication resource will be described. The information processing unit 153 adds the remaining resource information acquired by the information acquisition unit 154 to the relayed QoS guarantee request message.

  Further, in the second embodiment, the number of via terminals information indicating the number of via terminals, which is the number of wireless terminals relaying the QoS guarantee request message in the ad hoc network AH, is added to the QoS guarantee request message. The information processing unit 153 increments the number of via terminals (that is, adds 1) to the relayed QoS guarantee request message.

  On the other hand, in a state where the base station communication transceiver 130 is directly connected to the radio base station BS, the message notification unit 156 performs the QoS guarantee request when there are a plurality of candidate radio terminals for the base station connection instruction message. Based on the reception intensity information, the remaining resource information, and the number of via terminals information added to the message, one wireless terminal that is a notification destination of the base station connection instruction message is selected.

(2) Configuration Example of Message Next, configuration examples of the QoS guarantee request message, the base station connection instruction message, and the QoS guarantee result notification message will be described. FIG. 10 is a diagram illustrating a configuration example of each message according to the second embodiment.

  In the second embodiment, it is assumed that the ad hoc network AH is configured using a wireless LAN. Therefore, each message is an Ethernet (registered trademark) frame.

As shown in FIG.
The frame includes a field for storing a destination MAC address, a field for storing a source MAC address, a field for storing a frame type, a field for storing frame data, and a field for storing a CRC.

  The format of the frame data is different for each of the QoS guarantee request message, the base station connection instruction message, and the QoS guarantee result notification message.

  As shown in FIG. 10B, the frame data of the QoS guarantee request message has a type field, a request source field, a QoS request resource field, and a number of via terminals field. Further, when the QoS guarantee request message is relayed, a transit terminal field, a reception strength field, and a remaining resource field are added to the frame data of the QoS guarantee request message (not shown in FIG. 10B). 13).

  In the type field, identification information (here, 0x00) for identifying the QoS guarantee request message is stored. The request source field stores identification information (here, MAC address) of the source wireless terminal MS of the QoS guarantee request message. In the QoS request resource field, QoS (here, communication band) information requested by the source wireless terminal MS of the QoS guarantee request message is stored. The number of via terminals information described above is stored in the number of via terminals field. In the via terminal field, identification information (MAC address here) of the wireless terminal MS that relayed the QoS guarantee request message is stored. The reception strength field stores the above-described reception strength information. In the remaining resource field, the resource remaining amount information described above is stored.

  In the second embodiment, guaranteeable terminal information is also used as reception intensity information. Specifically, the wireless terminal MS that cannot guarantee QoS with the wireless base station BS uses the value indicating the out-of-range as reception strength information even if it is located within the wireless base station BS.

  As shown in FIG. 10 (c), the frame data of the base station connection instruction message includes a type field, an instruction target field, a QoS request source field, and a QoS request resource field. In the type field, identification information (here, 0x01) for identifying the base station connection instruction message is stored. In the instruction target field, identification information (MAC address in this case) of the wireless terminal MS that is the transmission destination (notification destination) of the base station connection instruction message is stored. In the QoS request source field, identification information (MAC address in this case) of the source wireless terminal MS of the QoS guarantee request message is stored. In the QoS request resource field, QoS (here, communication band) information requested by the source wireless terminal MS of the QoS guarantee request message is stored.

  As shown in FIG. 10D, the frame data of the QoS guarantee result notification message includes a type field, a notification target field, and a guarantee result field. In the type field, identification information (here, 0x02) for identifying the QoS guarantee result notification message is stored. In the notification target field, identification information (MAC address here) of the wireless terminal MS that is the transmission destination (notification destination) of the QoS guarantee result notification message is stored. The guarantee result field stores information indicating whether or not the QoS guarantee with the radio base station BS is successful.

(3) Operation of Radio Terminal Next, the operation of the radio terminal MS according to the second embodiment will be described. However, since the receiving operation of the base station connection instruction message and the receiving operation of the QoS guarantee result notification message are the same as those in the first embodiment, the receiving operation of the QoS guarantee request message will be described below.

  FIG. 11 is a flowchart showing an operation of receiving a QoS guarantee request message in the radio terminal MS according to the second embodiment.

  In step S601, the determination unit 152 determines whether or not the base station communication transmitting / receiving unit 130 is directly connected to the radio base station BS. When the base station communication transmitting / receiving unit 130 is directly connected to the radio base station BS (when it is the highest radio terminal MS), the process proceeds to step S602, and when it is not directly connected (the highest radio terminal MS). Otherwise, the process proceeds to step S607.

  In the following, the operation of the wireless terminal MS other than the highest wireless terminal and the operation of the highest wireless terminal MS will be described separately.

(3.1) Operation of wireless terminal MS other than the highest level The wireless terminal MS other than the highest level processes the QoS guarantee request message received by the message receiving unit 151 in the following procedure.

  In step S607, the information processing unit 153 increments the number of via terminals in the number of via terminals field in the QoS guarantee request message. Further, the information processing unit 153 adds identification information (MAC address) of the own wireless terminal MS in the transit terminal field in the QoS guarantee request message.

  In step S608, the determination unit 152 determines whether or not QoS guarantee with the radio base station BS is possible. If the QoS guarantee with the radio base station BS is possible, the process proceeds to step S609. If the QoS guarantee with the radio base station BS is not possible, the process proceeds to step S612.

  In step S609, the information processing unit 153 stores the reception strength information acquired by the information acquisition unit 154 in the reception strength field in the QoS guarantee request message. On the other hand, in step S612, the information processing unit 153 stores an out-of-range value (for example, −255 dBm) in the reception intensity field.

  In step S610, the information processing unit 153 stores the resource remaining amount information acquired by the information acquiring unit 154 in the remaining resource field of the QoS guarantee request message.

  In step S611, the message relay unit 155 transfers the QoS guarantee request message to the master.

(3.2) Operation of the highest radio terminal MS The highest radio terminal MS processes the QoS guarantee request message received by the message receiver 151 in the following procedure.

  In step S602, the information processing unit 153, based on the resource remaining amount information in the QoS guarantee request message, in the ad hoc network AH, each wireless terminal MS on the route from the source wireless terminal MS of the QoS guarantee request message to the own wireless terminal MS. It is determined whether or not the remaining QoS resource satisfies the request QoS of the source wireless terminal MS of the QoS guarantee request message.

  That is, if the QoS resource remaining amount of each wireless terminal MS on the route in the ad hoc network AH does not satisfy the requested QoS, even if QoS between the wireless base station BS and the highest wireless terminal MS is guaranteed, the QoS guarantee request The request QoS of the message source wireless terminal MS cannot be satisfied. For this reason, it is preferable to perform the determination process in step S602 in order to satisfy the QoS requirement of the source wireless terminal MS of the QoS guarantee request message more reliably. If the QoS of the QoS guarantee request message from the source wireless terminal MS is satisfied, the process proceeds to step S603; otherwise, the process proceeds to step S613.

  In step S603, the determination unit 152 determines whether or not QoS guarantee with the radio base station BS is possible. If the QoS guarantee with the radio base station BS is possible, the process proceeds to step S604, and if the QoS guarantee with the radio base station BS is not possible, the process proceeds to step S613. Note that the process of step S603 may be executed between step S601 and step S602.

  In step S604, the base station communication transceiver 130 requests QoS guarantee from the radio base station BS.

  In step S605, the base station communication transceiver 130 determines whether QoS guarantee with the radio base station BS has succeeded (established). If the QoS guarantee with the radio base station BS is successful, the process proceeds to step S606. If the QoS guarantee with the radio base station BS fails, the process proceeds to step S613.

  In step S606, the message notification unit 156 notifies the wireless terminal that has transmitted the QoS guarantee request message of a QoS guarantee result notification message indicating that the QoS guarantee with the radio base station BS is successful.

  On the other hand, in step S613, the message notification unit 156 is a radio terminal MS (hereinafter, guaranteeable terminal) capable of QoS guarantee with the radio base station BS based on the resource remaining amount information in the QoS guarantee request message. It is determined whether there is a guaranteeable terminal in which the remaining resource of each wireless terminal MS on the path from the sender wireless terminal MS of the QoS guarantee request message to the guaranteeable terminal satisfies the requested QoS. Here, the reason why the remaining resource of each wireless terminal MS on the route from the source wireless terminal MS of the QoS guarantee request message to the guaranteeable terminal is taken into consideration is the same as in step S602. If there is a guaranteeable terminal that satisfies the condition of step S613, the process proceeds to step S614. If there is no guaranteeable terminal that satisfies the condition, the process proceeds to step S621.

  In step S621, the message notification unit 156 notifies a QoS guarantee result notification message that the QoS guarantee with the radio base station BS has failed to the radio terminal that has transmitted the QoS guarantee request message.

  On the other hand, in step S614, the message notification unit 156 determines whether there are a plurality of guaranteeable terminals that satisfy the condition in step S613. If there are a plurality of guaranteeable terminals that satisfy the condition of step S613, the process proceeds to step S615. If there is one guaranteeable terminal that satisfies the conditions, the process proceeds to step S620. In step S620, the message notification unit 156 transmits a base station connection instruction message to one guaranteeable terminal that satisfies the condition in step S613.

  In step S615, the message notification unit 156 has one or more guarantable terminals having a radio field strength of a certain level or more among a plurality of guarantable terminals that satisfy the condition of step S613 based on the reception strength information in the QoS guarantee request message. Determine if it exists. The process proceeds to step S616 when there is one or more guaranteeable terminal having a radio field intensity of a certain level or more, and the process proceeds to step S619 when there is no guaranteeable terminal having a radio field intensity of a certain level or more.

  In step S619, the message notification unit 156, based on the reception strength information in the QoS guarantee request message, the guaranteeable terminal that has the maximum reception strength from the radio base station BS among the plurality of guaranteeable terminals that satisfy the condition of step S614. And a base station connection instruction message is transmitted to the specified guaranteeable terminal. In this way, when there is no guaranteeable terminal whose radio field strength is above a certain level, the base station connection instruction message is transmitted by transmitting the base station connection instruction message to the guaranteeable terminal whose reception strength is relatively maximum. The received guaranteeable terminal can be directly connected to the radio base station BS more reliably.

  On the other hand, in step S616, the message notification unit 156, based on the remaining resource information in the QoS guarantee request message, among the plurality of guaranteeable terminals that satisfy the condition in step S615, the guaranteeable terminal that has a certain amount of remaining resources. It is determined whether one or more exists. The process proceeds to step S617 when there is one or more guaranteeable terminals whose resource remaining amount is greater than or equal to a certain level, and the process proceeds to step S618 when there is no guaranteeable terminal whose resource remaining amount is greater than or equal to a certain amount. .

  In step S618, the message notification unit 156 identifies a guaranteeable terminal that has the maximum remaining resource among one or more guaranteeable terminals that satisfy the condition of step S615, based on the remaining resource information in the QoS guarantee request message. Then, a base station connection instruction message is transmitted to the specified guaranteeable terminal.

  In step S617, the message notification unit 156, based on the number-of-terminals information in the QoS guarantee request message, of the one or more guaranteeable terminals that satisfy the condition of step S616, from the source wireless terminal MS of the QoS guarantee request message A guaranteeable terminal having the smallest number of via terminals is identified, and a base station connection instruction message is transmitted to the identified guaranteeable terminal.

  In this way, when determining the terminal that can guarantee the transmission destination of the base station connection instruction message from among a plurality of terminals that can be guaranteed, the received radio wave intensity is the highest priority as the determination criterion as in steps S615 to S616, Next, the remaining resource amount is used as a determination criterion, and finally the number of via terminals is used as a determination criterion.

(4) Specific Example of Operation of Radio Communication System Next, a specific example of the operation of the radio communication system according to the second embodiment will be described. In this specific example, (4.1) Overall operation of wireless communication system, (4.2) Processing operation of QoS guarantee request message, (4.3) Processing operation of base station connection instruction message, (4.4) The processing operation of the QoS guarantee result notification message will be described.

(4.1) Overall Schematic Operation of Radio Communication System FIG. 12 is a diagram for explaining the overall schematic operation of the radio communication system 1B according to this example.

  In FIG. 12A, an ad hoc network AH is formed by the wireless terminals MS1 to MS9. Here, it is assumed that the wireless terminal MS5 requests a QoS guarantee of 4 Mbps, and that the wireless terminal MS1 directly connected to the wireless base station BS cannot guarantee the QoS with the wireless base station BS.

  Further, it is assumed that the radio terminals MS2 and MS3 can be directly connected to the radio base station BS and can guarantee QoS with the radio base station BS. Accordingly, the wireless terminals MS2 and MS3 can be candidates for the transmission destination of the base station connection instruction message from the wireless terminal MS1.

  The remaining QoS resource of the wireless terminal MS2 is 2 Mbps, and the remaining QoS resource of the wireless terminal MS3 is 5 Mbps. For this reason, there is a wireless terminal MS (wireless terminal MS2) that cannot satisfy the requested QoS (4 Mbps) on the route from the wireless terminal MS5 to the wireless terminal MS2. On the other hand, all the wireless terminals MS on the route from the wireless terminal MS5 to the wireless terminal MS3 can satisfy the requested QoS (4 Mbps).

  Accordingly, the wireless terminal MS1 transmits a base station connection instruction message with the wireless terminal MS3 as a transmission destination. As a result, as shown in FIG. 12B, the radio terminal MS3 connects directly to the radio base station BS and establishes a QoS guarantee. In addition, the wireless terminal MS3 disconnects from the wireless terminal MS2.

  Thus, the ad hoc network AH is divided into an ad hoc network AH1 having the radio terminal MS1 as the highest level and an ad hoc network AH2 having the radio terminal MS3 as the highest level.

(4.2) QoS guarantee request message processing operation Next, with reference to FIG. 13, each wireless terminal MS on the path from the wireless terminal MS5 to the wireless terminal MS1 processes the QoS guarantee request message in the situation shown in FIG. The operation to be performed will be described.

  As illustrated in FIG. 13, the radio terminal MS5 transmits a QoS guarantee request message in which the address of the radio terminal MS5 is stored in the request source field and a value indicating 4 Mbps is stored in the QoS request resource field to the radio terminal MS4. At this time, the frame data D1 of the QoS guarantee request message is one, and the number of via terminals is also zero.

  The radio terminal MS4 adds the frame data D2 to the QoS guarantee request message received from the radio terminal MS5 and relays the QoS guarantee request message to the radio terminal MS3. In the frame data D2, the address of the wireless terminal MS4 is stored in the via terminal field, the reception strength information of the wireless terminal MS4 (here, a value indicating out-of-service) is stored in the reception strength field, and the resource of the wireless terminal MS4 is stored in the remaining resource field. The remaining amount information (here, a value indicating 8 Mbps) is stored. Further, the wireless terminal MS4 increments the number of transit terminals to 1 in the frame data D1.

  The radio terminal MS3 adds the frame data D3 to the QoS guarantee request message received from the radio terminal MS4 and relays the QoS guarantee request message to the radio terminal MS2. In the frame data D3, the address of the radio terminal MS3 is stored in the via terminal field, the reception strength information (here, a value indicating -90 dBm) of the radio terminal MS3 is stored in the reception strength field, and the radio terminal MS3 is stored in the remaining resource field. Resource remaining amount information (here, a value indicating 5 Mbps) is stored. Further, the wireless terminal MS3 increments the number of transit terminals to 2 in the frame data D1.

  The radio terminal MS2 adds the frame data D4 to the QoS guarantee request message received from the radio terminal MS3 and relays the QoS guarantee request message to the radio terminal MS1. In the frame data D4, the address of the wireless terminal MS2 is stored in the via terminal field, the reception strength information (here, a value indicating -85 dBm) of the wireless terminal MS2 is stored in the reception strength field, and the wireless terminal MS3 is stored in the remaining resource field. Resource remaining amount information (here, a value indicating 2 Mbps) is stored. Further, the wireless terminal MS2 increments the number of transit terminals to 3 in the frame data D1.

  The wireless terminal MS1 that has received the QoS guarantee request message selects the wireless terminal MS3 as a transmission destination of the base station connection instruction message based on the frame data D1 to D4 in the QoS guarantee request message.

(4.3) Base Station Connection Instruction Message Processing Operation Next, a base station connection instruction message processing operation will be described with reference to FIG.

  As shown in FIG. 14, the radio terminal MS1 stores the address of the radio terminal MS3 in the instruction target field, stores the address of the radio terminal MS5 in the QoS request source field, and stores a value indicating 4 Mbps in the QoS request resource field. The base station connection instruction message is transmitted to the wireless terminal MS2.

  Next, the wireless terminal MS2 stores the address of the wireless terminal MS3 in the instruction target field, stores the address of the wireless terminal MS5 in the QoS request source field, and stores a value indicating 4 Mbps in the QoS request resource field. The message is transmitted to the wireless terminal MS3. That is, the radio terminal MS2 relays the base station connection instruction message received from the radio terminal MS1 to the radio terminal MS3 as it is.

(4.4) Processing Operation of QoS Guarantee Result Notification Message Next, the processing operation of the QoS guarantee result notification message will be described with reference to FIG.

  As illustrated in FIG. 15A, the radio terminal MS3 that has received the base station connection instruction message transmits a connection request and a QoS guarantee request to the radio base station BS.

  Next, as illustrated in FIG. 15B, the radio base station BS permits the connection request and the QoS guarantee request, and transmits a message indicating the connection success and the QoS guarantee success to the radio terminal MS3.

  Next, as illustrated in FIG. 15C, the radio terminal MS3 disconnects from the radio terminal MS2. As a result, the radio terminal MS3 becomes the highest radio terminal in the ad hoc network AH2, as shown in FIG. 12 (b).

  Next, as shown in FIG. 15 (d), since the address of the wireless terminal MS5 is stored in the QoS request source field in the base station connection instruction message, the wireless terminal MS3 uses the wireless terminal MS5 as a transmission destination and performs QoS. A QoS guarantee result notification message indicating the success of the guarantee is transmitted.

(5) Operation / Effect According to the second embodiment, the radio terminal MS other than the highest level adds reception strength information and remaining resource information to the relayed QoS guarantee request message. As a result, the highest-order wireless terminal MS can grasp the reception strength and remaining resource status of the lower-order wireless terminal MS than the highest-order wireless terminal MS. The transmission destination of the station connection instruction message can be appropriately selected.

  Specifically, when the highest radio terminal MS has a plurality of guarantable terminals in a radio terminal MS lower than the highest radio terminal MS, the reception strength is relatively high among the plurality of guarantable terminals. The base station connection instruction message is transmitted to the guaranteeable terminal that becomes the maximum. For this reason, the guaranteeable terminal that has received the base station connection instruction message can directly connect to the radio base station BS more reliably.

  In addition, when there is a plurality of guaranteeable terminals in the radio terminal MS lower than the highest radio terminal MS, the highest radio terminal MS has a relatively maximum remaining resource among the plurality of guaranteeable terminals. The base station connection instruction message is transmitted to the guaranteeable terminal. For this reason, the guaranteeable terminal that has received the base station connection instruction message can more reliably secure communication resources for the source wireless terminal MS of the QoS guarantee request message.

  Further, the radio terminal MS other than the highest level increments the number of via terminals in response to the relayed QoS guarantee request message. When there are a plurality of guarantable terminals in the radio terminal MS lower than the highest radio terminal MS, the highest radio terminal MS has the smallest number of via terminals among the plurality of guarantable terminals. A base station connection instruction message is transmitted to the guaranteeable terminal. Thereby, the number of via terminals can be minimized and transmission delay can be suppressed.

[Other Embodiments]
As described above, the present invention has been described by the first embodiment and the second embodiment. However, it should not be understood that the description and drawings constituting a part of this disclosure limit the present invention. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art.

  In the first and second embodiments described above, the base station connection instruction message is a message instructing direct connection with the radio base station BS, QoS guarantee with the radio base station BS, and disconnection from the master. However, the configuration may be such that direct connection with the radio base station BS, QoS guarantee with the radio base station BS, and disconnection from the master are instructed by separate messages.

  In the second embodiment described above, a case has been described in which all three of reception strength information, resource remaining amount information, and routed terminal number information are used as determination criteria. Only one of them may be used as a criterion.

  In the first embodiment and the second embodiment described above, a mobile phone terminal having a wireless LAN communication function is illustrated as the wireless terminal MS. However, the mobile phone terminal is not limited to a mobile phone terminal, and a notebook PC or personal digital assistance ( PDA) or the like. Further, not only a portable wireless terminal but also an ad hoc network including a fixed wireless terminal may be configured.

  Thus, it should be understood that the present invention includes various embodiments and the like not described herein. Therefore, the present invention is limited only by the invention specifying matters in the scope of claims reasonable from this disclosure.

1 is an overall schematic configuration diagram of a radio communication system according to a first embodiment of the present invention. It is a schematic block diagram of the radio | wireless terminal which concerns on 1st Embodiment of this invention. It is a functional block block diagram of the radio | wireless terminal which concerns on 1st Embodiment of this invention. It is a sequence diagram which shows the operation pattern 1 of the radio | wireless communications system which concerns on 1st Embodiment of this invention. It is a sequence diagram which shows the operation | movement pattern 2 of the radio | wireless communications system which concerns on 1st Embodiment of this invention. 6 is a flowchart showing a reception operation of a QoS guarantee request message in the wireless terminal according to the first embodiment of the present invention. It is a flowchart which shows the reception operation | movement of the base station connection instruction | indication message which concerns on 1st Embodiment of this invention. It is a flowchart which shows reception operation | movement of the QoS guarantee result notification message which concerns on 1st Embodiment of this invention. It is a functional block block diagram of the radio | wireless terminal which concerns on 2nd Embodiment of this invention. It is a figure which shows the structural example of each message which concerns on 2nd Embodiment of this invention. 7 is a flowchart showing a reception operation of a QoS guarantee request message in a wireless terminal according to the second embodiment of the present invention. It is a figure for demonstrating the whole schematic operation | movement of the radio | wireless communications system which concerns on 2nd Embodiment of this invention. It is a figure for demonstrating the processing operation | movement of the QoS guarantee request message in the radio | wireless communications system which concerns on 2nd Embodiment of this invention. It is a figure for demonstrating the processing operation of the base station connection instruction | indication message in the radio | wireless communications system which concerns on 2nd Embodiment of this invention. It is a figure for demonstrating the processing operation | movement of the QoS guarantee result notification message in the radio | wireless communications system which concerns on 2nd Embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1A, 1B ... Wireless communication system, 130 ... Base station communication transmission / reception part, 140 ... Ad hoc communication transmission / reception part, 150 ... Control part, 151 ... Message reception part, 152 ... Determination part, 153 ... Information processing part, 154 ... Information acquisition part 155 ... Message relay unit, 156 ... Message notification unit, 160 ... Input unit, 170 ... Output unit, 180 ... Storage unit, 181 ... Master / slave storage unit

Claims (14)

A wireless terminal constituting a tree-structured network with a wireless terminal directly connected to a wireless base station as a top level,
A direct connection unit for direct connection to the radio base station;
Guarantee requesting a guarantee of communication quality, which is a quality of communication with the radio base station, from a radio terminal located in a lower position in the tree structure network in a state where the direct connection unit is directly connected to the radio base station A request receiver for receiving requests;
When the request receiving unit receives the guarantee request, if the communication quality cannot be guaranteed, the guaranteeable terminal is based on the guaranteeable terminal information that can guarantee the communication quality added to the guarantee request. An instruction notification unit for notifying an instruction for direct connection with the radio base station and an instruction for guaranteeing the communication quality;
A wireless terminal comprising:   The instruction notifying unit notifies the wireless terminal that is a transmission source of the guarantee request that the guarantee of the communication quality is impossible when the guarantee request terminal information is not added to the guarantee request. The wireless terminal according to 1.   2. The wireless terminal according to claim 1, wherein when there are a plurality of guaranteeable terminals, the instruction notification unit selects a guaranteeable terminal that is a notification destination of the instruction from the plurality of guaranteeable terminals. The guarantee request includes reception strength information indicating a reception strength of a radio signal received from the radio base station by a radio terminal located in a lower position in the tree-structured network,
When there are a plurality of guaranteeable terminals, the instruction notification unit selects a guaranteeable terminal having the highest reception strength from among the plurality of guaranteeable terminals based on the reception strength information. The wireless terminal according to claim 3, which is selected as The guarantee request includes resource remaining amount information indicating a remaining amount of communication resources that can be used for communication in the ad hoc network by a wireless terminal located in a lower position in the tree structure network,
When there are a plurality of guaranteeable terminals, the instruction notification unit selects a guaranteeable terminal having the largest remaining amount of communication resources from the plurality of guaranteeable terminals based on the resource remaining amount information. The wireless terminal according to claim 3, which is selected as a guaranteeable terminal. The guarantee request includes routed terminal number information indicating the number of routed terminals that is the number of wireless terminals that relayed the warranty request in the tree-structured network,
When there are a plurality of guaranteeable terminals, the instruction notification unit determines whether the number of routed terminals from the wireless terminal that is the transmission source of the guarantee request from the plurality of guaranteeable terminals based on the number of routed terminal information. The wireless terminal according to claim 3, wherein the least guaranteeable terminal is selected as a guaranteeable terminal of the notification destination. The guarantee request includes resource remaining amount information indicating a remaining amount of communication resources that can be used for communication in the tree-structured network by wireless terminals located in a lower position in the tree-structured network,
The instruction notifying unit, when all wireless terminals on the route from the wireless terminal that is the transmission source of the guarantee request to the guaranteeable terminal in the tree-structured network do not have a certain resource remaining amount, The wireless terminal according to claim 1, notifying the wireless terminal that has transmitted the guarantee request that the communication quality cannot be guaranteed. A wireless terminal constituting a tree-structured network with a wireless terminal directly connected to a wireless base station as a top level,
A direct connection unit for direct connection to the radio base station;
Guarantee requesting a guarantee of communication quality, which is a quality of communication with the radio base station, from a radio terminal located in a lower position in the tree structure network in a state where the direct connection unit is not directly connected to the radio base station A request receiver for receiving requests;
A guarantee request relay unit that relays the guarantee request received by the request receiving unit to a wireless terminal located at a higher level in the tree-structured network;
When the request receiving unit receives the guarantee request, if the communication quality with the radio base station can be guaranteed, the communication quality is guaranteed for the guarantee request relayed by the guarantee request relay unit. An information adding unit for adding guaranteeable terminal information indicating that it is possible ,
The guarantee request relay unit relays the guarantee request to which the guaranteeable terminal information is added to the wireless terminal located at the higher rank . An instruction receiving unit for receiving an instruction for direct connection with the radio base station and an instruction for guaranteeing the communication quality from a radio terminal located in a higher rank in the tree-structured network;
9. The direct connection unit according to claim 8, wherein when the instruction receiving unit receives the instruction, the direct connection unit directly connects to the radio base station and requests the radio base station to guarantee the communication quality. Wireless terminal. A reception intensity information acquisition unit for acquiring reception intensity information indicating the reception intensity of a radio signal received from the radio base station;
The radio terminal according to claim 8, wherein the information adding unit adds the reception strength information acquired by the reception strength information acquisition unit to the guarantee request relayed by the guarantee request relay unit. A resource remaining amount information acquiring unit for acquiring resource remaining amount information indicating a remaining amount of communication resources available for communication in the tree-structured network;
The wireless terminal according to claim 8, wherein the information adding unit adds the resource remaining amount information acquired by the resource remaining amount information acquiring unit to the guarantee request relayed by the warranty request relay unit. The guarantee request includes routed terminal number information indicating the number of routed terminals that is the number of wireless terminals that relayed the warranty request in the tree-structured network,
The wireless terminal according to claim 8, wherein the information adding unit adds the number of via terminals to which the number of via terminals is added to the guarantee request relayed by the guarantee request relay unit. A wireless communication method used for a wireless terminal constituting a tree-structured network having a wireless terminal directly connected to a wireless base station as a top level,
Receiving a guarantee request for requesting a guarantee of communication quality, which is a quality of communication with the radio base station, from a radio terminal located in a lower position in the tree-structured network in a state of being directly connected to the radio base station; When,
When the guarantee request is received in the receiving step, if the communication quality can not be guaranteed, the guaranteeable terminal is based on the guaranteeable terminal information that can guarantee the communication quality added to the guarantee request. And notifying the direct connection instruction with the radio base station and the communication quality guarantee instruction;
A wireless communication method comprising: A wireless communication method used for a wireless terminal constituting a tree-structured network having a wireless terminal directly connected to a wireless base station as a top level,
Receiving a guarantee request for requesting a guarantee of communication quality, which is a quality of communication with the radio base station, from a radio terminal located in a lower position in the tree structure network in a state where the radio base station is not directly connected to the radio base station; When,
When the guarantee request is received in the receiving step, if the communication quality with the radio base station can be guaranteed, it can be guaranteed that the communication quality can be guaranteed for the guarantee request. Adding terminal information;
Relaying the guarantee request to which the guaranteeable terminal information is added to a wireless terminal located at a higher level in the tree-structured network;
A wireless communication method comprising:

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