JP5787351B2 - Relay node device, ad hoc network, and wireless relay method used therefor - Google Patents

Description

  The present invention relates to a relay node device, an ad hoc network, and a wireless relay method used therefor, and more particularly to the construction of an ad hoc network in which respective terminals perform direct wireless communication with each other.

  When a plurality of terminals perform direct wireless communication with each other in the ad hoc mode, communication exceeding the wireless reachable range can be performed via the plurality of terminals by connecting the communication by the bucket relay method. This is multi-hop communication.

  In the above-described ad hoc network, it is impossible to search for a power saving route, and each terminal performs data communication with more wireless output than necessary. In order to solve this problem, in Patent Document 1 described below, in wireless output setting, normal power is used for data communication that requires real-time performance, and power saving is performed for data communication that does not require real-time performance.

  Further, in the above ad hoc network, the communication speed is reduced when the relay nodes overlap. In order to solve this problem, in Patent Document 2 below, radio channel reservation is performed, and transmission of some of the peripheral nodes of the route node is temporarily stopped to prevent a reduction in communication speed.

Japanese Patent No. 4531683 Japanese Patent No. 4168152

  To construct an ad hoc network that performs multi-hop communication in the above-described ad hoc mode, it is possible to select an efficient and stable route depending on the environment, to prevent a decrease in communication speed when the route overlaps, There is a problem of whether optimization can be performed.

  In Patent Document 1, power saving is performed for data communication that does not require real-time performance, but detailed power saving settings cannot be performed. In Patent Document 2, transmission of some of the peripheral nodes of the route node is temporarily stopped to prevent a reduction in communication speed, but an improvement in throughput of the entire network is not considered.

  Accordingly, an object of the present invention is to solve the above-described problems, and in a multistage relay connection of ad hoc communication, a relay node device, an ad hoc network, and a radio relay method used for them that can suppress a decrease in communication speed according to the communication environment Is to provide.

The relay node device according to the present invention is a relay node device used for an ad hoc network in which a plurality of relay node devices perform direct wireless communication with each other in the ad hoc mode and perform multihop communication by connecting the communication by the bucket relay method. And
First detection means for detecting a priority of each of the plurality of relay node devices, a communication bandwidth used, and a link speed between the relay nodes;
Second detection means for detecting duplication of first and second communication paths of different paths by each of the plurality of relay node devices;
One of the first and second communication paths based on the detection result of the first detection means when the second detection means detects an overlap of the first and second communication paths. And control means for changing.

  An ad hoc network according to the present invention includes the relay node device described above.

The wireless relay method according to the present invention is a wireless relay method used for an ad hoc network in which a plurality of relay node devices perform direct wireless communication with each other in an ad hoc mode, and the communication is connected by a bucket relay method. And
A first detection process in which the relay node device detects a priority of each of the plurality of relay node devices, a communication bandwidth used, and a link speed between the relay nodes; and a first of different paths by each of the plurality of relay node devices. And a second detection process for detecting duplication of the second communication path, and detection of the first detection process when duplication of the first and second communication paths is detected in the second detection process. Based on the result, a control process for changing one of the first and second communication paths is executed.

  By adopting the configuration and operation as described above, the present invention provides an effect that a reduction in communication speed can be suppressed according to the communication environment in multistage relay connection for ad hoc communication.

It is a block diagram which shows the structural example of the wireless base station (relay node apparatus) by the 1st Embodiment of this invention. It is a figure which shows the construction example of the ad hoc network by the 1st Embodiment of this invention. It is a figure which shows the construction example of the ad hoc network by the 1st Embodiment of this invention. It is a figure which shows the construction example of the ad hoc network by the 1st Embodiment of this invention. It is a flowchart which shows the switching operation | movement of a communication path when the communication paths of the wireless base station 1 by the 1st Embodiment of this invention overlap. It is a flowchart which shows the procedure which lowers | hangs the radio | wireless output of the radio base station 1 by the 1st Embodiment of this invention. It is a figure which shows the construction example of the ad hoc network by the 2nd Embodiment of this invention.

  Next, embodiments of the present invention will be described with reference to the drawings. First, an outline of an ad hoc network according to the present invention will be described. In the ad hoc network according to the present invention, when performing direct wireless communication with each other in the ad hoc mode, multi-hop communication is performed in which the communication is connected by the bucket relay method.

  In an ad hoc network, when the path from terminal a to terminal b and the path from terminal c to terminal d overlap, a decrease in communication speed occurs. Therefore, in the present invention, the function in each relay node (radio base station) is used to detect the priority of each relay node, the communication bandwidth used, and the link speed between the relay nodes. In the communication between the terminal a and the terminal b and the communication between the terminal c and the terminal d, the communication having a low priority is changed to another route, thereby preventing the communication speed from being lowered.

  Further, in the present invention, if the used bandwidth of each relay node is within the link speed between the relay nodes, there is no problem even with the same route, so the route is not changed.

  Furthermore, in the present invention, when communication is performed from the first relay node to the next second relay node on the path communicating from the terminal a to the terminal b, if the radio environment around the second relay node is bad, the radio environment Communication from the fourth relay lead around the third relay node to the third relay node and communication from the third relay node to the fifth relay node from the fourth relay node to the second relay node. The communication speed of communication to the relay node and communication from the second relay node to the fifth relay node is reduced.

  In this case, in the present invention, when communicating from the first relay node to the next second relay node, the beacon level of the surrounding relay node is monitored in advance, and the monitoring result is used for route selection. Choose a stable route.

  In the present invention, when the use band of the relay node that uses the selected route is lower than the link speed between the relay nodes, the wireless output of the relay node is lowered, and the link speed is reduced to near the use band to save power. be able to.

  As described above, in the present invention, it is possible to optimize the radio output and communication path of the relay node by reducing the power consumption of the relay node and suppressing the decrease in the communication speed according to the communication environment.

  In other words, the present invention is characterized by suppressing a reduction in communication speed according to the power saving of the relay node and the communication environment in the multistage relay connection in which the multi-hop communication is performed in the ad hoc mode. In other words, in the present invention, in multi-stage relay connection of ad hoc communication that performs multi-hop communication in ad hoc mode, comfortable communication is provided by selecting a relay node according to the radio condition of the relay node, the priority of communication data, and the like. It is characterized by doing.

  FIG. 1 is a block diagram showing a configuration example of a radio base station (relay node apparatus) according to the first embodiment of the present invention. In FIG. 1, the radio base station 1 includes a control unit 11, a radio unit 12, and a storage unit 13. The control unit 11 includes a communication information detection unit 111, a duplication detection unit 112, and a path control unit 113. And an output control unit 114.

  The communication information detection unit 111 detects the priority of each radio base station, the used communication band, and the link speed between the radio base stations. The duplication detection unit 112 detects, for example, an overlap between a path communicating from the terminal a to the terminal b and a path communicating from the terminal c to the terminal d in the local station.

  Based on the detection results of the communication information detection unit 111 and the duplication detection unit 112, the route control unit 113, for example, changes the route in the route communicating from the terminal a to the terminal b and the route communicating from the terminal c to the terminal d. Control. The output control unit 114 controls the radio output from the radio unit 12 of the local station based on the detection result of the communication information detection unit 111.

  2 to 4 are diagrams showing examples of construction of an ad hoc network according to the first embodiment of the present invention. A construction example of an ad hoc network according to the first embodiment of the present invention will be described with reference to FIGS. In FIGS. 2 to 4, A to I denote radio base stations, and a to d denote terminals.

  As shown in FIG. 2, in the communication between the terminal a and the terminal b and the communication between the terminal c and the terminal d, the radio base station is duplicated (between the radio base station D and the radio base station E). ) Occurs, the wireless base station D with the overlapping communication path uses the data of the wireless base stations C, I, and E received by the wireless unit 12 to control each wireless base station with the control unit 11 (communication information detecting unit 111). The priorities of the stations C, I, and E are detected and stored in the storage unit 13. Similarly, in the control unit 11 (communication information detection unit 111), the use bands of the radio base stations C, I, and E are also stored in the storage unit 13.

  Further, the control unit 11 compares the link speed between the radio base station D and the radio base station E detected by the communication information detection unit 111 with the band used by each radio base station C, I, E, and The communication between the terminal c and the terminal d is lower in priority than the communication between the terminal a and the terminal b, and the use band of each of the radio base stations C, I and E exceeds the link speed between the radio base stations. In the case where the communication node between the terminal c and the terminal d is not routed between the wireless base station D and the wireless base station E (wireless base stations G, H, I in FIG. 4) Changed to

  The control unit 11 compares the use band of the radio base stations BCD and BFD detected by the communication information detection unit 111 with the link speed of the radio base stations BCD and BFD. When the use band is low, the output of the wireless unit 12 is lowered from the wireless output and link speed data stored in the storage unit 13 to a level at which connection can be established at the corresponding link speed (see FIG. 3).

  FIG. 5 is a flowchart showing the operation of switching the communication path when the communication paths of the radio base station 1 overlap according to the first embodiment of the present invention, and FIG. 6 shows the radio according to the first embodiment of the present invention. 4 is a flowchart showing a procedure for reducing the radio output of the base station 1. The operation of the radio base station 1 according to the first embodiment of the present invention will be described with reference to FIGS. 5 and 6 can be realized by executing a program stored in the storage unit 13 by the control unit 11 of the radio base station 1.

  First, the switching operation when the communication paths overlap between the radio base station D and the radio base station E (see FIG. 2) will be described with reference to FIG. The following is processing of the control unit 11 of the radio base station D.

  When the relay node overlap occurs (detected by being in communication with three radio base stations in the radio base station D shown in FIG. 2), the control unit 11 determines the communication amount of each radio base station as the communication amount. If it is higher (YES in step S1 in FIG. 5), the communication priority is confirmed (step S3 in FIG. 5). When the communication amount does not exceed the communicable amount of the radio base station (NO in step S1 in FIG. 5), the control unit 11 does not change the radio base station because there is no problem with relay node duplication (FIG. 5). 5 step S2).

  When the communication amount exceeds the communicable amount of the radio base station (YES in step S1 in FIG. 5) and there is a difference in priority (YES in step S3 in FIG. 5), the control unit 11 The radio base station I is instructed to change the low radio base station to a route that does not overlap (radio base stations G, H, I in FIG. 4) (step S4 in FIG. 5).

  When there is no difference in priority (NO in step S3 in FIG. 5), the control unit 11 changes the route of the overlapping wireless base station (in this case also, the route of the wireless base stations G, H, and I in FIG. 4). The radio base station I is instructed to do so (step S5 in FIG. 5).

  When changing the route of the radio base station, the radio base station I communicates with another radio base station H upon receiving an instruction [notification that communication (connection) is not possible] from the radio base station D, and from the terminal c. A communication path to the terminal d is formed.

  Next, a procedure for reducing the radio output of the radio base station B will be described with reference to FIG. The following is processing of the control unit 11 of the radio base station B.

  After the start of communication between the radio base stations B-C, the control unit 11 compares the use band of the radio base station B with the link speed between the radio base stations B-C, and if the link speed is not higher than the use band (FIG. 6 NO in step S11), the wireless output of the wireless base station B is not changed (step S12 in FIG. 6).

  If the link speed is higher than the use band (YES in step S11 in FIG. 6), the control unit 11 measures the reception level and noise level between the radio base stations B and C (step S13 in FIG. 6). In this case, the control unit 11 acquires the measurement result of the reception level and noise level of the radio base station C via the radio unit 12.

  When the link speed cannot be lowered from the measurement level to the use band of the radio base station B (NO in step S14 in FIG. 6), the control unit 11 does not change the radio output of the radio base station B (step S15 in FIG. 6).

  When the link speed can be lowered from the measurement level to the use band of the radio base station B (YES in step S14 in FIG. 6), the control unit 11 lowers the radio output of the radio base station B (step S14 in FIG. 6).

  As described above, in the present embodiment, by performing the processing as described above, the wireless output and the communication path of the relay node (wireless base station) are optimized from the communication priority order, so that communication is performed according to the communication environment. A decrease in speed can be suppressed.

  In the present embodiment, the radio output of the radio base station is optimized by optimizing the radio output and communication path of the relay node (radio base station) from the communication speed with the connection destination by processing as described above. It is possible to save power by suppressing the above.

  The second embodiment of the present invention is devised in that a plurality of relay nodes (radio base stations) are used based on information on communication priority and used bandwidth. FIG. 7 is a diagram showing an example of construction of an ad hoc network according to the second embodiment of the present invention.

  In FIG. 7, large-capacity real-time data such as streaming data is transmitted from a plurality of radio base station communication paths (communication paths of radio base stations ABCDE, radio base stations A-G- The transmission of data through the HI communication path) prevents frame dropping and the like from occurring.

  In this case, in the present embodiment, there are places where the communication speed is low in the communication path between the terminals a and b, and if the communication speed between the terminal a and the radio base station A is high, a frame drop or the like occurs. Sometimes. Therefore, in the present embodiment, the data from the terminal a is transferred separately to the communication path of the radio base station A-B-C-D-E and the communication path of the radio base station A-G-H-I. Yes.

  In the radio base station A, when communication is performed between the radio base stations B-C, data from the terminal a is sent to the radio base station G. In addition, the wireless base station A sends data from the terminal a to the wireless base station B when communication is performed between the wireless base stations GH. In this way, even when the communication speed between the terminal a and the radio base station A is high, the radio base station A can prevent occurrence of frame dropping or the like by sending each of the two communication paths in a time division manner. it can.

  In the present invention, it is possible to optimize the radio output by monitoring the signal reception intensity at the radio base station and notifying the opposite radio base station of the situation (reception intensity) between the radio base stations. .

  A part or all of the above embodiment can be described as in the following supplementary notes, but is not limited to the following description.

[Appendix 1]
A wireless relay method used for an ad hoc network that performs multi-hop communication by connecting the communication by a bucket relay method when each of a plurality of relay node devices perform direct wireless communication in an ad hoc mode,
A first detection process in which the relay node device detects a priority of each of the plurality of relay node devices, a communication bandwidth used, and a link speed between the relay nodes; and a first of different paths by each of the plurality of relay node devices. And a second detection process for detecting duplication of the second communication path, and detection of the first detection process when duplication of the first and second communication paths is detected in the second detection process. A control process for changing one of the first and second communication paths based on the result, and
The wireless relay method according to claim 1, wherein in the control process, a communication path having a low priority among the first and second communication paths is changed to another path.

[Appendix 2]
The wireless relay method according to supplementary note 1, wherein, in the control process, a communication path that is duplicated after the first and second communication paths is changed to another path.

[Appendix 3]
The relay node device performs a process of comparing the use bandwidth of the own device with a link speed between the own device and the next-stage device, and a process of controlling a change in the wireless output of the own device according to the comparison result. The wireless relay method according to Supplementary Note 1 or Supplementary Note 2, which is executed.

[Appendix 4]
The wireless relay method according to appendix 3, wherein the link speed is lowered to the vicinity of the use band in the process of controlling the change of the wireless output of the own apparatus.

[Appendix 5]
The wireless relay method according to any one of appendix 1 to appendix 4, wherein the relay node device divides and transfers input data to a plurality of communication paths according to a communication amount.

[Appendix 6]
When the relay node device transfers the input data using a communication path in which the input data is input at high speed and there is a part where the communication speed is low, the input is performed using the communication path and another communication path. The wireless relay method according to appendix 5, wherein the data is transferred.

[Appendix 7]
A wireless relay method used for an ad hoc network that performs multi-hop communication by connecting the communication by a bucket relay method when each of a plurality of relay node devices perform direct wireless communication in an ad hoc mode,
A first detection process in which the relay node device detects a priority of each of the plurality of relay node devices, a communication bandwidth used, and a link speed between the relay nodes; and a first of different paths by each of the plurality of relay node devices. And a second detection process for detecting duplication of the second communication path, and detection of the first detection process when duplication of the first and second communication paths is detected in the second detection process. A control process for changing one of the first and second communication paths based on the result, and
The wireless relay method according to claim 1, wherein in the control process, an overlapping communication path after the first and second communication paths is changed to another path.

[Appendix 8]
A wireless relay method used for an ad hoc network that performs multi-hop communication by connecting the communication by a bucket relay method when each of a plurality of relay node devices perform direct wireless communication in an ad hoc mode,
A first detection process in which the relay node device detects a priority of each of the plurality of relay node devices, a communication bandwidth used, and a link speed between the relay nodes; and a first of different paths by each of the plurality of relay node devices. And a second detection process for detecting duplication of the second communication path, and detection of the first detection process when duplication of the first and second communication paths is detected in the second detection process. A control process for changing one of the first and second communication paths based on the result, and
The relay node device performs a process of comparing the use bandwidth of the own device with a link speed between the own device and the next-stage device, and a process of controlling a change in the wireless output of the own device according to the comparison result. A wireless relay method that is executed.

[Appendix 9]
The wireless relay method according to appendix 8, wherein in the process of controlling the change of the wireless output of the device itself, the link speed is lowered to the vicinity of the use band.

[Appendix 10]
A wireless relay method used for an ad hoc network that performs multi-hop communication by connecting the communication by a bucket relay method when each of a plurality of relay node devices perform direct wireless communication in an ad hoc mode,
A first detection process in which the relay node device detects a priority of each of the plurality of relay node devices, a communication bandwidth used, and a link speed between the relay nodes; and a first of different paths by each of the plurality of relay node devices. And a second detection process for detecting duplication of the second communication path, and detection of the first detection process when duplication of the first and second communication paths is detected in the second detection process. Executing a control process for changing one of the first and second communication paths based on the result; and
The wireless relay method, wherein the relay node device transfers input data divided into a plurality of communication paths according to a communication amount.

[Appendix 11]
When the relay node device transfers the input data using a communication path in which the input data is input at high speed and there is a part where the communication speed is low, the input is performed using the communication path and another communication path. The wireless relay method according to appendix 10, wherein data is transferred.

1, A to I Radio base station 11 Control unit 12 Radio unit 13 Storage unit 111 Communication information detection unit 112 Duplicate detection unit 113 Path control unit 114 Output control unit a, b terminal

Claims (9)

When each of a plurality of relay node devices perform direct wireless communication with each other in an ad hoc mode, the relay node device is used in an ad hoc network that performs multi-hop communication by connecting the communication by a bucket relay method,
First detection means for detecting a priority of each of the plurality of relay node devices, a communication bandwidth used, and a link speed between the relay nodes;
Second detection means for detecting duplication of first and second communication paths of different paths by each of the plurality of relay node devices;
One of the first and second communication paths based on the detection result of the first detection means when the second detection means detects an overlap of the first and second communication paths. A relay node apparatus comprising: a control means for changing   2. The relay node device according to claim 1, wherein the control unit changes a communication path having a low priority among the first and second communication paths to another path.   3. The relay node apparatus according to claim 1, wherein the control unit changes a communication path that overlaps later from the first and second communication paths to another path.   And means for comparing the bandwidth used by the own apparatus with the link speed between the own apparatus and the next stage apparatus, and means for controlling a change in the wireless output of the own apparatus according to the comparison result. The relay node device according to any one of claims 1 to 3.   5. The relay node apparatus according to claim 4, wherein the means for controlling the change of the wireless output of the own apparatus lowers the link speed to the vicinity of the use band.   The relay node device according to any one of claims 1 to 5, wherein the input data is divided and transferred to a plurality of communication paths in accordance with a communication amount.   When the input data is transferred using a communication path in which the input data is input at a high speed and the communication speed is low, the input data is transferred using the communication path and another communication path. The relay node device according to claim 6, wherein:   An ad hoc network comprising the relay node device according to any one of claims 1 to 7. A wireless relay method used for an ad hoc network that performs multi-hop communication by connecting the communication by a bucket relay method when each of a plurality of relay node devices perform direct wireless communication in an ad hoc mode,
A first detection process in which the relay node device detects a priority of each of the plurality of relay node devices, a communication bandwidth used, and a link speed between the relay nodes; and a first of different paths by each of the plurality of relay node devices. And a second detection process for detecting duplication of the second communication path, and detection of the first detection process when duplication of the first and second communication paths is detected in the second detection process. And a control process for changing one of the first communication path and the second communication path based on the result.

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