JP2005323266A - Wireless network communication system, relay wireless terminal used for system, wireless terminal of transmission source, and routing method for wireless communication path - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the power consumption at a node by determining a communication path with good communication efficiency suitable for wireless communication even if an obstacle impeding the wireless communication is interposed in the communication path, to prevent respective nodes from having imbalance in power consumption, to solve problems of a break, an error of data, etc., when music data, moving picture data, etc., are reproduced in real time, and to preferentially and speedily transmit emergency data etc. <P>SOLUTION: A communication path through which packet data etc., are transmitted is determined on the basis of a communication evaluation value regarding communication performance calculated based upon communication capability such as a wireless communication speed between nodes, received electric field intensity of a wireless radio wave, the remaining electric energy of the nodes, or position information on the nodes. Further, a communication path corresponding to the kind of data is determined. Furthermore, relaying nodes constituting an existent communication path are forcibly or optionally released and a new communication path using the released relaying nodes is determined. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a wireless network communication system applied to an autonomous distributed wireless network configured by wirelessly connecting a plurality of wireless terminals so that they can wirelessly communicate with each other, and more particularly, from a wireless terminal that is a data source. The present invention relates to processing (so-called routing processing) for determining a wireless communication path that can efficiently transmit transmitted data to a destination wireless terminal.

In recent years, with the development of wireless communication technology and the spread of portable terminals such as notebook computers and mobile phones, personal computers, PDAs, and mobile phones that can be wirelessly connected without requiring access points and base stations that are essential for wireless LAN services, etc. An ad hoc network (independently distributed wireless network) composed of only a plurality of wireless terminals is known.
This ad hoc network is an area where a fixed communication infrastructure such as the access point, base station, or communication line in a wired network cannot be used (for example, a disaster area) or an area where the communication infrastructure is not sufficiently established ( For example, when a network is required in a remote area, or when a small network in a limited range is required immediately, there is an advantage that a network can be constructed inexpensively, easily and instantly. Attention has been paid. However, the ad hoc network has begun to attract attention only recently, and many technical problems still remain in the practical use of this network.

As described above, the ad hoc network is a network composed of only a plurality of wireless terminals. In this network connection form (network topology), data sent from the data source is relayed by one or more other wireless terminals and sequentially transferred to other adjacent wireless terminals by the other wireless terminals. Thus (such data communication is called multi-hop communication), a communication path from the data source to the data destination is formed.
In order to realize such multi-hop communication, generally, processing (routing processing) for determining (or selecting) a data communication path according to a predetermined routing protocol is performed. In recent years, a number of technical methods related to the routing protocol and the routing method have been proposed, and examples of the technical methods are described in Patent Document 1 and Patent Document 2. In the known routing methods described in these patent documents, each wireless terminal equipped with GPS (Global Positioning System) acquires and stores temporary or accurate location information of other wireless terminals in the ad hoc network. Based on this position information, the wireless communication path that selects the shortest path length from the data transmitting wireless terminal to the data receiving wireless terminal is selected.
JP 2001-268127 A JP 2002-171283 A

However, the known routing method described in the above-described known documents (Patent Document 1 and Patent Document 2) is relatively applied by being applied to an ad hoc network constructed in a place with good visibility (a place where there is no communication obstruction factor). Although a communication path with good communication efficiency can be determined (or selected), for example, as shown in FIG. 5, there are many communication obstruction factors such as an obstacle 10 that hinders wireless communication between the nodes n3 and n8. In an ad hoc network X that is built in an existing urban area or indoors, the communication is interrupted by the obstacle 10 and is affected by fading or multipath. Therefore, even if the known routing method is applied, the communication efficiency is high. The communication path is not necessarily selected. That is, the communication path with the shortest physical path length based on the position information obtained by the GPS (in FIG. 5, the data transmission source wireless terminal is node n4 and the destination wireless terminal is node n8). Even if the communication path Rb (n4 → n3 → n8) is selected, if there is an obstacle between the paths, the transmission loss of the wireless communication increases due to communication interruption or fading (the transmission speed decreases) For this reason, there is a problem that communication takes a long time as compared with the case where data is not transmitted through another communication path that is not shortest but has no obstacles. FIG. 6 shows a topology table 60 of a wireless communication path determined based on a physical distance between nodes by a known routing method.
On the other hand, in order to prevent transmission loss between the paths through which the obstacle is interposed, by increasing the communication power consumption of the wireless terminals (nodes n3 and n8 in FIG. 5) at both ends of the path, the transmission speed, etc. Although it is possible to maintain the communication quality at a predetermined level, it is not practical because a huge amount of communication power is consumed, and there is a problem that an imbalance of power consumption occurs between wireless terminals. Will do. In particular, ad-hoc networks are often built with mobile terminals such as notebook PCs and PDAs that are driven by portable batteries, which increases power consumption, drastically reduces battery charge, and shortens the drive time of mobile terminals. It can develop into a serious problem.
In addition, the wireless communication speed of the wireless terminals constituting the ad hoc network depends on the specifications of wireless communication devices such as wireless adapters used in each terminal (for example, wireless standards such as IEEE802.11a, b, g, or Bluetooth). Since there may be different cases, it must be said that in practice it is extremely difficult to select a communication path with good communication efficiency based only on the position information of each wireless terminal.

  In addition, the above-described known routing method constructs an ad hoc network in consideration of communication efficiency (transmission efficiency) and certainty of connection (relay), and constructs a network in consideration of data types and the like. It is not a thing. Normally, a wide variety of data is transmitted over a network. Depending on the type of data, the communication quality standards of the communication paths that can be transmitted may differ. For example, a communication path that transmits text data, e-mail data, or the like does not require so high communication quality, but a communication path that transmits important data such as music or video data that requires real-time performance or the like receives it. Therefore, a relatively high communication quality is required so that no interruption occurs when the above-mentioned voice or moving image data is reproduced in real time on the receiving terminal side, or a code error or the like does not occur in the data. Nevertheless, if a communication path is selected without considering the data type or the like, there is a possibility that interruption during data reproduction or data error may occur.

  Further, in the above known routing method, for example, when a route for transmitting e-mail data that does not require urgent is already formed on the network, it is assumed that urgent data (emergency data) is transmitted. However, when a relay terminal (connection point) that constitutes a route capable of efficiently transmitting the emergency data in the shortest time is used as a route for transmitting the e-mail data, the route for transmitting the emergency data As a result, the shortest route is not selected, and another route that requires more time or inferior communication efficiency is selected. That is, there is a problem that data cannot be transmitted in the shortest time even though there is urgent data. All of these problems are due to the fact that the above network has been constructed taking into account only the reliability of communication efficiency (transmission efficiency) and connection (relay).

Accordingly, the present invention has been made in view of the above circumstances, and a first object of the present invention is based on two or more pieces of information regarding communication capability even when a failure that interferes with wireless communication is present in the communication path. The communication evaluation value related to the communication performance is obtained, and the communication efficiency is improved by selecting a communication path with good communication efficiency suitable for wireless communication based on the communication evaluation value, and the communication consumed by the wireless terminal. To provide a radio network communication system, a relay radio terminal, a source radio terminal, and a radio communication path routing method capable of reducing power consumption and preventing occurrence of power consumption imbalance among terminals. It is in.
The second purpose is to select a wireless communication path based on different criteria depending on the type of data, thereby causing problems such as interruptions or data errors when music data, moving image data, etc. are reproduced in real time. It is an object of the present invention to provide a wireless network communication system, a relay wireless terminal, a transmission source wireless terminal, and a wireless communication route routing method that can eliminate the problem.
Further, a third object is to provide a wireless network communication system, a relay wireless terminal, a source wireless terminal, and a wireless network communication system that enable rapid data transmission by preferentially securing a communication path for transmitting emergency data and the like. An object of the present invention is to provide a method for routing wireless communication paths.

In order to achieve the above object, the present invention provides a wireless network communication system used in an autonomous distributed wireless network configured by wirelessly connecting a plurality of wireless terminals so that they can wirelessly communicate with each other. In a wireless network communication system in which a wireless terminal of a transmission source performs wireless communication directly or indirectly by relaying one or more other wireless terminals and indirectly wirelessly connecting to a wireless terminal of a destination of the data Each of the plurality of wireless terminals acquires communication capability information for acquiring information on two or more communication capabilities of direct wireless communication performed with all other wireless terminals directly connected to the wireless terminal. And a communication evaluation value related to the performance of the direct wireless communication based on the information related to the communication capability acquired by the communication capability information acquisition unit. By comprising anda relay communication evaluation value calculating means for output is configured as a wireless network communication system according to claim (Claim 1).
In this way, since the communication evaluation value related to the communication performance between the wireless terminals is calculated, the communication efficiency of the communication path between the wireless terminals or from the transmission source to the destination is comprehensively determined from the calculated communication evaluation value. It becomes possible to do. As a result, for example, when communication efficiency decreases due to an obstacle that interferes with communication in the communication path where the physical distance from the source to the destination is the shortest, the communication path that is the shortest Although the path length becomes long, it becomes possible to select a communication path with higher communication efficiency and transmit data, and as a result, the communication time can be shortened and the transmission speed can be improved.

In this case, each of the plurality of wireless terminals further includes communication evaluation value transmitting means for transmitting the communication evaluation value calculated by the relay side communication evaluation value calculating means to the transmitting wireless terminal. The wireless terminal receives the communication evaluation value transmitted by the communication evaluation value transmitting means, and based on the communication evaluation value received by the communication evaluation value receiving means, And a first communication path determining means for determining a wireless communication path through which the data is transmitted between the wireless terminal and the destination wireless terminal. 2).
As a result, for example, even when an obstacle exists between the wireless terminal that is the source of data and the wireless terminal that is the destination of the data, the communication path with the obstacle, that is, the communication path with low communication quality is By detouring, a wireless communication path with good communication efficiency suitable for data transmission is determined (selected). As a result, communication time can be shortened and communication efficiency can be improved. Also, as in the past, a large amount of communication power is not consumed for data communication between wireless terminals with obstacles, so that power consumption can be reduced, and power consumption between wireless terminals can be reduced. The quantity imbalance can be eliminated. In addition, since a wireless communication path to the destination wireless terminal is established on the wireless terminal side of the data transmission source, the communication path is selected every time data is relayed on the other wireless terminal side that relays the data. In terms of eliminating the need for unnecessary routing processing, it greatly contributes to improving communication efficiency.

  The first communication path determination unit determines a radio communication path through which the data is transmitted from a plurality of radio communication paths determined based on the communication evaluation value received by the communication evaluation value receiving unit. Therefore, even if the wireless communication path with the highest total communication evaluation value is suddenly disconnected, the total communication evaluation value is obtained from the plurality of wireless communication paths. Since the second highest wireless communication path can be determined immediately, there is no need to reconstruct and determine the wireless communication path, reducing the time required to reconstruct the path when the communication path is disconnected Thus, the processing burden required for reconstruction can be reduced.

Here, the present invention may be considered as a system configuration in which the communication evaluation value is calculated by the source wireless terminal based on information on the communication capability acquired by the plurality of wireless terminals. .
That is, a wireless network communication system used in an autonomous distributed wireless network configured by wirelessly connecting a plurality of wireless terminals so that they can perform wireless communication with each other. In a wireless network communication system that performs wireless communication by relaying one or more other wireless terminals and indirectly connecting to the wireless terminal that is the destination of the data, each of the plurality of wireless terminals includes: Communication capability information acquisition means for acquiring information on two or more communication capabilities of direct wireless communication performed with all other wireless terminals directly connected to the wireless terminal; and the communication capability information acquisition means Communication capability information transmitting means for transmitting information related to the communication capability acquired by the transmission source wireless terminal to the transmission source wireless terminal, Based on the communication capability information receiving means for receiving information on the communication capability transmitted by the communication capability information transmitting means, and the information on the communication capability received by the communication capability information receiving means, the performance of the direct wireless communication It may be configured as a wireless network communication system, characterized by comprising a communication evaluation value calculation means on the transmission side for calculating communication evaluation values related to the above (claim 4).

Further, the present invention may be understood as a system configuration for determining a wireless communication path for transmitting the data according to the type of data transmitted from the terminal device as the transmission source.
That is, a wireless network communication system used in an autonomous distributed wireless network configured by wirelessly connecting a plurality of wireless terminals so that they can perform wireless communication with each other. In a wireless network communication system in which wireless communication is performed by relaying one or more other wireless terminals and indirectly wirelessly connecting to the wireless terminal that is the destination of the data, A second communication path determining means for determining a wireless communication path for transmitting the data between the source wireless terminal and the destination wireless terminal according to the type of the transmitted data; It may be configured as a wireless network communication system characterized in that (Claim 5).
As a result, even if the communication path can efficiently transmit data such as text data, if data such as a moving picture cannot be transmitted with high quality, another communication path with higher communication quality can be used. Therefore, it is possible to effectively prevent interruption of transmitted data and occurrence of code errors. Also, when transmitting emergency data that requires an emergency, the emergency data is the shortest even if it is a wireless terminal (relay terminal) that is used to configure another existing (default) wireless communication path. As long as it is used for a route for transmission over time, the relay terminal in use can be opened and used for a wireless terminal that relays the emergency data. As a result, the emergency data can be preferentially transmitted.

  In this case, each of the plurality of wireless terminals has communication capability for acquiring information on two or more communication capabilities of direct wireless communication performed with all other wireless terminals directly connected to the wireless terminal. An information acquisition unit; a relay side communication evaluation value calculation unit that calculates a communication evaluation value related to the performance of the direct wireless communication based on the information about the communication capability acquired by the communication capability information acquisition unit; and the relay side communication Communication evaluation value transmitting means for transmitting the communication evaluation value calculated by the evaluation value calculating means to the source wireless terminal, the source wireless terminal being transmitted by the communication evaluation value transmitting means A communication evaluation value receiving means for receiving the communication evaluation value; a communication evaluation threshold relating to the performance of the direct wireless communication predetermined according to the type of data to be transmitted; and the communication Communication evaluation value comparing means for comparing the communication evaluation value received by the value receiving means, and the second communication path determining means is configured to transmit the transmission based on a comparison result by the communication evaluation value comparing means. It is conceivable that a wireless communication path through which the data is transmitted is determined between the original wireless terminal and the destination wireless terminal. Note that the communication evaluation threshold value is stored in a storage medium (storage means) or the like in the transmission source wireless terminal, and the communication evaluation threshold value in the storage medium can be set to a value desired by the user. desirable.

  By the way, when a wireless communication path is determined with priority given to emergency data or the like, relay terminals constituting an existing (default) wireless communication path are forcibly released to transmit the emergency data. . However, when the relay terminal is released, the convenience of the user of the relay terminal or the user of the source terminal device that has transmitted data to the predetermined wireless communication path may be lost. Therefore, each of the plurality of wireless terminals sets whether to permit relaying of data having a higher priority than the predetermined data when the wireless terminal configures a predetermined wireless communication path for transmitting the predetermined data. Interrupt relay permission setting means for performing transmission, and setting state transmission means for transmitting the setting state by the interrupt relay permission setting means to the terminal device of the transmission source, wherein the wireless terminal of the transmission source A wireless communication system configured to further include a setting state reception unit that receives the setting state transmitted by the transmission unit, wherein the second communication path determination unit receives the setting state reception unit. If a wireless communication path for transmitting the data between the source wireless terminal and the destination wireless terminal is determined according to the set state, 7.) without convenience of the user is lost, it is possible to achieve a higher utility value wireless network communication system.

  A communication path storage means for storing the wireless communication path determined by the first communication path determination means and / or the second communication path determination means; And a data transmission means for transmitting the data based on the wireless communication path stored in the wireless communication system (Claim 8), and stored in the communication path storage means. Data transmission through a wireless communication path is realized. In this case, the communication path storage means preferably stores a plurality of wireless communication paths sorted in an order corresponding to the total value of the communication evaluation values, and the data transmission means includes, for example, the above-described data transmission means. It is preferable that the data is transmitted in order of the route having the highest communication evaluation value.

  Here, as the communication capability information acquisition means, for example, after the plurality of wireless terminals receive wireless connection request signals transmitted to the plurality of wireless terminals in the wireless network by the source wireless terminal, It is conceivable that the information related to the communication capability is acquired (claim 9). Thus, in the wireless terminal that is the source, the communication evaluation value is always calculated based on the latest information, and the wireless communication path is determined based on the communication evaluation value. Therefore, the communication path is disconnected during data transmission. Can reduce the anxiety factor.

  In addition, the communication capability information acquisition unit acquires information on two or more communication capabilities of the direct wireless communication performed with other wireless terminals satisfying a predetermined wireless communication condition at the plurality of wireless terminals. It is preferable that it is a thing (Claim 10). Here, as the wireless communication condition, for example, the separation distance from another wireless terminal is within a predetermined distance, or the number of relays (hop count) to another wireless terminal is within a predetermined number of times. Or the field strength value of the received radio wave is greater than or equal to a predetermined value, or the communication speed is greater than or equal to a predetermined speed. In general, since it is rare to directly perform wireless communication with a wireless terminal that does not satisfy such wireless communication conditions, in other words, it is frequently performed only between wireless terminals that satisfy the wireless communication condition (for example, between adjacent wireless terminals). Since wireless communication is assumed to be performed, information on two or more communication capabilities of direct wireless communication performed with other wireless terminals satisfying the wireless communication condition is acquired, and the above information is acquired based on the acquired information. It is considered sufficient to calculate a communication evaluation value with a wireless terminal that satisfies the wireless communication condition. Thereby, the burden of the process of calculating the communication evaluation value with the wireless terminal that does not satisfy the wireless communication condition is reduced, and the time spent for the process is reduced.

  Further, the relay side communication evaluation value calculation means or the transmission side communication evaluation value calculation means periodically performs the communication evaluation value based on the information on the communication capability periodically acquired by the communication capability information acquisition unit. May be calculated (claim 11). In this case, it is desirable that storage means for storing the communication evaluation value calculated periodically is provided in the terminal device of the transmission source. As a result, when the transmitting wireless terminal transmits data, it can immediately determine the wireless communication path based on the communication evaluation value and transmit the data. Processing time until data is transmitted is greatly reduced.

Further, the communication evaluation value transmitting means receives the wireless connection request signal transmitted by the source wireless terminal after the plurality of wireless terminals receive the communication evaluation value together with a response signal of the received wireless connection request signal. It is desirable that the value is transmitted to the wireless terminal as the transmission source (claim 12).
Further, the communication capability of the direct wireless communication may be a wireless communication speed between wireless terminals, a received electric field strength of a radio wave, a remaining power amount of the wireless terminal, or position information of the wireless terminal. ).

Further, the present invention is a wireless terminal that constitutes the above self-distributed wireless network, and can also be understood as a relay wireless terminal that relays data.
That is, the present invention provides a plurality of wireless terminals that form an autonomous distributed wireless network by being wirelessly connected to each other, and the data transmitted from the wireless terminal that is the source by wireless communication through the wireless network is transmitted. In a relay wireless terminal that relays and forwards the data to a destination wireless terminal, between the relay wireless terminal and all other wireless terminals in the wireless network that are directly wirelessly connected to the relay wireless terminal Communication capability information acquisition means for acquiring information regarding two or more communication capabilities of direct wireless communication performed in the above, and information on the performance of the direct wireless communication based on the information regarding the communication capability acquired by the communication capability information acquisition means A relay-side communication evaluation value calculating means for calculating a communication evaluation value; Even, it is possible to solve the problem (claim 14).
In this case, the relay wireless terminal further includes communication evaluation value transmitting means for transmitting the communication evaluation value calculated by the relay-side communication evaluation value calculating means to the source wireless terminal. (Claim 15).
And an interrupt relay permission setting means for setting whether to permit relaying of data having a higher priority than the predetermined data when the wireless terminal constitutes a predetermined wireless communication path for transmitting the predetermined data. It is preferable that the relay wireless terminal further comprises setting state transmitting means for transmitting the setting state by the interrupt relay permission setting means to the terminal device of the transmission source (claim 16).

In addition, the present invention is a wireless terminal that constitutes the above self-distributed wireless network, and can also be understood as a wireless terminal that transmits data.
That is, a plurality of wireless terminals that form a self-distributed wireless network by being wirelessly connected to each other, and directly or one or more other wireless terminals with a destination wireless terminal of data to be transmitted The wireless terminal that is the source of the data that performs wireless communication through the wireless network by relaying and indirectly connecting to the wireless network receives a predetermined communication evaluation value transmitted from the one or more other wireless terminals. The data is transmitted between the source wireless terminal and the destination wireless terminal based on the communication evaluation value receiving means and the communication evaluation value received by the communication evaluation value receiving means. Alternatively, it may be configured as a source wireless terminal characterized by comprising first communication path determining means for determining two or more wireless communication paths (claims). 17).

  Similarly, the present invention is a plurality of wireless terminals that constitute an autonomous distributed wireless network by being wirelessly connected to each other, and directly or in combination with a wireless terminal that is a destination of data to be transmitted. Communication capability information transmitting means possessed by the plurality of wireless terminals in the wireless terminal that is the source of the data that performs wireless communication via the wireless network by relaying and indirectly wirelessly connecting the other wireless terminals A communication capability information receiving means for receiving information relating to the predetermined communication capability transmitted by the communication means, and wireless connection directly to the plurality of wireless terminals based on the information relating to the communication capability received by the communication capability information receiving means. Transmitting side communication evaluation value calculation means for calculating a communication evaluation value related to the performance of direct wireless communication performed with all other wireless terminals to be performed. It is also possible to capture as the source of the wireless terminal characterized by (claim 18). Even the transmission source wireless terminal configured in this way can solve the above-described problem.

  Furthermore, the present invention provides a plurality of wireless terminals constituting a self-distributed wireless network by being wirelessly connected to each other, directly with a destination wireless terminal of data to be transmitted, or one or more other terminals. In the wireless terminal that is the source of the data that performs wireless communication via the wireless network by relaying the wireless terminal indirectly and wirelessly connecting the wireless terminal according to the type of the data to be transmitted, It can also be understood as a source wireless terminal characterized by comprising a second communication path determining means for determining a wireless communication path through which the data is transmitted between the terminal and the destination wireless terminal. It is possible (claim 19).

Further, the present invention may be understood as a wireless communication route routing method for performing processing corresponding to each means included in the wireless network communication system.
That is, a wireless communication path for data transmitted in an autonomous distributed wireless network configured by wirelessly connecting a plurality of wireless terminals so that they can communicate with each other, and relaying one or more wireless terminals In the routing method of the wireless communication path formed by the above, information on two or more communication capabilities of direct wireless communication performed with all other wireless terminals directly wirelessly connected to the wireless terminal is acquired. A communication evaluation value calculating step that calculates a communication evaluation value related to the performance of the direct wireless communication based on the information related to the communication capability acquired in the communication capability information acquisition step; and the communication evaluation value. Based on the communication evaluation value calculated in the calculation step, a wireless communication path for data transmitted through the wireless network is determined. A first communication path determining step of, can be regarded as a routing method of a wireless communication path, characterized by comprising comprises a (claim 20).

  Further, the present invention is a wireless communication path for data transmitted in an autonomous distributed wireless network configured by wirelessly connecting a plurality of wireless terminals so that they can wirelessly communicate with each other. In the routing method of the wireless communication path formed by relaying the wireless communication path, it relates to two or more communication capabilities of direct wireless communication performed with all other wireless terminals that are directly wirelessly connected to the wireless terminal. A communication capability information acquisition step for acquiring information; a communication evaluation value calculation step for calculating a communication evaluation value regarding the performance of the direct wireless communication based on the information regarding the communication capability acquired by the communication capability information acquisition step; A communication evaluation threshold relating to the performance of the direct wireless communication determined in advance according to the type of data to be transmitted, and the communication evaluation value calculation step. The communication evaluation value comparison step for comparing the communication evaluation values calculated by the network, and the data between the source wireless terminal and the destination wireless terminal based on the comparison result of the communication evaluation value comparison step And a second communication route determining step for determining a wireless communication route through which the wireless communication path is transmitted.

  As described above, the present invention provides each of the plurality of wireless terminals of the wireless network communication system used in the self-sustained distributed wireless network configured by wireless connection of a plurality of wireless terminals so that they can perform wireless communication with each other. Communication capability information acquisition means for acquiring information on two or more communication capabilities of direct wireless communication performed with all other wireless terminals directly connected to the wireless terminal; and the communication capability information Since there is provided a relay side communication evaluation value calculation means for calculating a communication evaluation value related to the performance of the direct wireless communication based on the information related to the communication capability acquired by the acquisition means, the communication performance between the wireless terminals is A communication evaluation value can be calculated. Accordingly, it is possible to comprehensively determine the communication efficiency of the communication path between the wireless terminals or from the transmission source to the reception destination from the calculated communication evaluation value. As a result, for example, even when an obstacle that interferes with communication is present in the communication path where the physical distance from the source to the destination is the shortest, the path length is longer than this shortest path, but the communication efficiency is better. Data can be transmitted by selecting a communication path, and as a result, communication time and the like can be shortened.

  Each of the plurality of wireless terminals is provided with communication evaluation value transmitting means for transmitting the calculated communication evaluation value to the transmission source wireless terminal, and the transmission source wireless terminal includes the communication evaluation value. A communication evaluation value receiving means for receiving the communication evaluation value transmitted by the transmitting means; and a wireless terminal of the transmission source and the wireless of the destination, based on the communication evaluation value received by the communication evaluation value receiving means. Since there is provided a first communication route determining means for determining a wireless communication route through which the data is transmitted to and from the terminal, for example, between the wireless terminal that is the data source and the wireless terminal that is the destination Even if an obstacle is present in the network, a communication path with the obstacle, that is, a communication path with low communication quality is bypassed and a wireless communication path with high communication efficiency suitable for data transmission is determined (selected). Can be done. This shortens the communication time and improves the communication efficiency. Also, as in the past, a large amount of communication power is not consumed for data communication between wireless terminals with obstacles, so that power consumption can be reduced, and power consumption between wireless terminals can be reduced. The quantity imbalance can be eliminated. In addition, since a wireless communication path to the destination wireless terminal is established on the wireless terminal side of the data transmission source, the communication path is selected every time data is relayed on the other wireless terminal side that relays the data. This eliminates the need for wasteful routing processing.

  The first communication path determination unit determines a radio communication path through which the data is transmitted from a plurality of radio communication paths determined based on the communication evaluation value received by the communication evaluation value receiving unit. Therefore, by storing the plurality of defined wireless communication paths, even if the wireless communication path having the highest total communication evaluation value is suddenly disconnected, the stored information is stored. From the plurality of wireless communication paths, another wireless communication path having the second highest communication evaluation value can be determined as a wireless communication path through which data is transmitted. This eliminates the need for determination, shortens the time required for path reconstruction when the communication path is disconnected, and reduces the processing load required for the reconstruction.

Further, even when the present invention is regarded as a wireless network communication system in which the communication evaluation value is calculated by the source wireless terminal based on the information on the communication capability acquired by the plurality of wireless terminals, the calculation is performed. It is possible to comprehensively determine the communication efficiency of the data communication path from the communication evaluation value.
Further, by capturing the present invention as a wireless network communication system that determines a wireless communication path for transmitting data transmitted in accordance with the type of data transmitted from the terminal device that is the transmission source, data such as text data is assumed. If data such as moving images cannot be transmitted with high quality even if it is a communication path that can efficiently transmit video, another communication path with higher communication quality is determined as the communication path for the data such as moving images. For this reason, it is possible to effectively prevent the occurrence of interruption or data code error when the transmitted moving image data or the like is reproduced. Also, when transmitting emergency data that requires emergency, the emergency data can be efficiently transmitted in the shortest time even if it is a wireless terminal (relay terminal) that is used to construct another existing wireless communication path. If it is used for a route that often transmits, it can be used for a wireless terminal that relays the emergency data by opening the relay terminal in use. As a result, the emergency data can be preferentially transmitted.
In addition, in accordance with a setting state such as interrupt relay permission transmitted from a plurality of wireless terminals such as the relay terminal, data is transmitted between the source terminal device and the destination terminal device. Since the communication path is determined, the emergency communication data is always prioritized and the wireless communication path is determined, so that the relay terminal is contrary to the intention of the user of the relay terminal or the terminal device of the transmission source. Is not forcibly released, and a wireless network communication system with higher utility value can be realized without losing the convenience of the user.

Hereinafter, embodiments and examples of the present invention will be described with reference to the accompanying drawings so that the present invention can be understood. It should be noted that the following embodiments and examples are examples embodying the present invention, and are not of a nature that limits the technical scope of the present invention.
<< First Embodiment >>
First, a first embodiment of the present invention will be described with reference to FIGS. 1 is a schematic connection diagram of the ad hoc network X1 showing the wireless communication path Ra determined by the routing method according to the first embodiment of the present invention, and FIG. 2 is determined based on the communication evaluation value between nodes. FIG. 3 is a flowchart for explaining an example of the routing process (including the first communication path determination process) executed at the source node, and FIG. FIG. 5 is a schematic connection diagram of an ad hoc network X showing a wireless communication path determined by a conventional routing method, and FIG. 6 is a physical connection between nodes. FIG. 7 is a table showing the physical communication path topology information determined based on the distance, and FIG. 7 is a table showing the physical linear distance between the nodes. A.

Here, the wireless network communication system according to the first embodiment of the present invention will be described with reference to the schematic connection diagram of FIG. Here, X1 in FIG. 1 is an ad hoc network (an example of an autonomous distributed wireless network, which is configured by wirelessly connecting nodes n1 to n8 (corresponding to a plurality of wireless terminals) to each other so as to perform wireless communication. (Abbreviated as “network”). In the network X1, an obstacle 10 (communication hindering factor) such as a building is interposed between the nodes n1 to n6 and the node n8 in order to simplify the description of the first embodiment. It is assumed that the nodes n1 to n6 and the node n8 can directly communicate with each other under the influence of the obstacle 10 but are in a communication environment in which sufficient communication quality cannot be obtained. In addition, it is assumed that there is no obstacle or the like that hinders communication between the node n7 and the node n8 and between the nodes n1 to n7, and a communication environment in which good communication quality can be obtained.
In the wireless network communication system according to the present invention, each of the nodes constituting the network X1 performs processing according to a predetermined routing protocol, so that a wireless terminal (for example, a node n4 and a node n4) that transmits data such as packets is transmitted. The same applies to the following description.) Directly or indirectly through one or more other wireless terminals to indirectly receive data (for example, the node n8. The same applies to the following description). ) And a wireless communication system. By configuring the system in this way, for example, the node n4 is directly wirelessly connected to the nodes n2, n3, and n6 adjacent to the node n4, or the nodes n2, n3, and n6 are relayed. By indirectly connecting to the nodes n1, n5, n7, and n8 wirelessly, data communication between the node n4 and each of the nodes is realized.

The nodes n1 to n8 are examples of wireless terminals constituting the network X1, and are mobile terminals such as notebook personal computers, PDAs, and mobile phones that can be carried around. These nodes are configured to include a known wireless communication device having a communication control processor (CCP: Communication Control Processing), a memory, a wireless antenna, and the like. Since each component of the node is well known in the art, detailed description thereof is omitted here.
Each of the nodes has a routing function for determining (or selecting) a communication path for data transmitted through the network X1. That is, the communication control processor executes a routing process described later according to a predetermined routing protocol, thereby determining a wireless communication path for transmitting the data.

The memory provided in each node stores a routing program configured according to the routing protocol. The routing function is realized by the routing program being executed by the communication control processor of each node. The routing process executed by the routing function will be described later using a flowchart.
The memory stores a topology table indicating a wireless communication path for transmitting data from each node to another node. In other words, the memory of each node stores a topology table indicating a wireless communication path to another node when each node is a source. For example, the topology table when the data source is the node n4 is the topology table 20 shown in FIG. 2, and this topology table 20 is stored in the memory of the node n4. Therefore, the data transmitted from the node n4 is relayed by the nodes constituting the wireless communication path according to the wireless communication path specified by the topology table 20 and transmitted to a predetermined destination node.

  Here, an example of the routing process executed by the communication control processor of each node constituting the wireless network communication system used in the network X1 will be described with reference to the flowcharts of FIGS. However, in the following description, in order to simplify the description of the processing, the wireless communication path of the data when the data source is the node n4 and the final destination of the data transmitted from the node n4 is the node n8. Although the routing process will be described, it is not intended to limit the technical scope of the present invention. In the network X1, as described above, the obstacle 10 that inhibits communication between the nodes n1 to n6 and the node n8 is interposed. FIG. 3 is a flowchart for explaining an example of the procedure of the routing process (including the first communication route determination process) executed by the data source node n4. FIG. 4 is a flowchart for all the nodes constituting the network X1. It is a flowchart explaining an example of the procedure of the communication evaluation value calculation process performed. In the figure, S10, S20,... Indicate processing procedure (step) numbers. The routing process is started from step S10, and the communication evaluation value calculation process is started from step S110.

  First, the routing processing procedure executed at the node n4 will be described with reference to the flowchart of FIG. When the node n4 is instructed to transmit the data by designating the node n8 as the destination, the wireless connection request signal is transmitted (broadcast) to all the nodes existing in the network X1 shown in FIG. (S10 in FIG. 3). In this case, the type information of the data transmitted from the node n4 and the transmission source node are the node n4 so that the transmitted data and the data transmission source can be recognized at the node that has received the wireless connection request signal. It is desirable that information indicating the presence or the like be attached (added) to the wireless connection request signal and transmitted. After the wireless connection request signal is transmitted, the node n4 enters a standby state for waiting for a communication evaluation value (data indicating) transmitted from the node that has received the wireless connection request signal.

Next, the procedure of the communication evaluation value calculation process executed in all the nodes that have received the wireless connection request signal will be described using the flowchart of FIG. When the wireless connection request signal transmitted from the node n4 is received by each node in the network X1 (S110 in FIG. 3), thereafter, each node follows the procedure of steps S120 to S140 described below. , Processing (communication capability information acquisition processing) for acquiring information on two or more communication capabilities of direct wireless communication performed between all the nodes directly wirelessly connected to each node is performed.
First, in step S120, a test signal is transmitted (broadcast) to all nodes in the network X1 (S120). At this time, data related to the remaining battery level (remaining electric energy), wireless communication speed, etc. of the node on the transmission side of the test signal, which is an example of information related to the communication capability, is attached to the test signal together with the test signal. Sent.
When the test signal is received at each of the nodes (S130), the received field strength (corresponding to information related to communication capability) at the time of reception is measured at the node that has received the test signal (S140). For example, at the node n1 that has received the test signal transmitted from the nodes n2 to n8, the received radio wave intensity of the test signal between the node n1 and each of the nodes n2 to n8 is received simultaneously with the reception of the test signal. It is measured (S140). At this time, the node n1 receives (acquires) data relating to the remaining battery level and the wireless communication speed of the nodes n2 to n8 transmitted together with the received test signal. Similarly, the received signal strength of the test signal is measured at each of the other nodes, and data relating to the remaining battery level, wireless communication speed, and the like is received.

After that, based on the received electric field strength measured in step S140 and the information about the communication capacity such as the remaining battery level and the wireless communication speed acquired when the test signal is received, it is directly connected to each node. A communication evaluation value process for calculating a communication evaluation value related to the performance of direct wireless communication performed with all other nodes that perform wireless communication is executed in step S150. That is, the communication evaluation value is calculated brute forcely among all the nodes in the network X1. Specifically, this communication evaluation value is calculated based on the following formula (1).
That is, the slower communication speed B (xy) between the node nx and the node ny, the weighted average value of the remaining battery level between the node nx and the node ny is V (xy), the node nx and the node ny. If the weighted average value of the received electric field strength values between them is E (xy), the communication evaluation value D (xy) between the node nx and the node ny can be expressed by the following equation (1).
D (xy) = [alpha] * B (xy) + [beta] * V (xy) + [gamma] E (xy) (1)
Here, α, β, and γ in the above equation (1) represent predetermined weighting factors of the communication speed, the remaining battery level, and the received electric field strength value, respectively. Further, the node nx and the node ny indicate any two nodes in the network X1. The reason why the slower communication speed B is used as the calculation factor is that if there is a difference in the communication speed between the nodes, communication can be performed only at the slower communication speed. It is not limited to. For example, a weighted communication speed of the communication speed from the node nx to the node ny and the communication speed from the node ny to the node nx may be used as B (xy) in the above equation (1). In addition, when the node is provided with position information acquisition means such as GPS for acquiring the position information of the node itself or another node, the GPS is used as an element for calculating the communication evaluation value D (xy). It is desirable to use the acquired position information. The above formula (1) is an example of a calculation formula for calculating the communication evaluation value, and is not particularly limited thereto.

When the communication evaluation value is calculated in each of the nodes, subsequently, in step S160, the calculated communication evaluation value (data indicating) is transmitted to the data source node n4 (communication evaluation value transmission process). ). At this time, as a method for transmitting the communication evaluation value, it is conceivable to transmit the communication evaluation value together with a response signal to the wireless connection request signal transmitted from the source node n2.
In the first embodiment, the description will be made assuming that the communication evaluation value is calculated in each node. For example, the remaining battery level, the wireless communication speed, etc. received in each node in step S130. Even in the embodiment in which the data, the received electric field intensity measured in step S140, and the like are transmitted to the source node n4, the communication evaluation value between the nodes is calculated by the node n4. It is possible to determine a wireless communication path that improves the performance.

Next, the procedure of the routing process executed by the node n4 will be described again using the flowchart of FIG. In step S20, it is determined whether or not the communication evaluation value transmitted from each node in step S160 has been received via the wireless antenna of the source node n4 (communication evaluation value receiving process). Here, if it is determined that the communication evaluation value has been received, then in step S30, based on the received communication evaluation value, the transmission source node and the data reception destination node are connected. A wireless communication path through which data transmitted from the node is transmitted is determined (first communication path determination process). Specifically, based on the received communication evaluation value, a plurality of routes assumed between the source node n4 and the destination node n8, for example, “n4 → n3 → n8”, “n4 → First, a plurality of routes such as “n3 → n7 → n8”, “n4 → n6 → n7 → n8” are obtained, and the route Ra “n4 → n6 → n7 → n8 ”(see FIG. 1) is determined as a wireless communication path for transmitting data. The wireless communication path determined here is configured by relaying the data and one or more relay nodes (corresponding to relay wireless terminals) that transfer the data to a destination node wirelessly connected to each other. This refers to the data communication path used.
In the conventional routing process, the data communication path is determined (or selected) simply based only on the physical distance between the nodes. For example, as the wireless communication path between the node n4 and the node n8, The route Rb [n4 → n3 → n8] (see FIG. 8) having the shortest route length has been determined (or selected). However, according to the routing processing of the present invention, calculation is performed in consideration of the communication capability between nodes. Since the communication route having the highest communication evaluation value is determined based on the communication evaluation value, the wireless communication route between the node n4 and the node n8 is affected by the obstacle 10. The route length is longer than the route Rb [n4 → n3 → n8] while avoiding the routes [n3 → n8] and [n6 → n8] in which the communication quality (communication speed, received electric field strength, etc.) is reduced. Overall High path quality, i.e., the path shown in Figure 1 which is not affected by the obstacle 10 Ra [n4 → n6 → n7 → n8] is determined as a data transmission path.

  When the wireless communication path is determined in step S30, information indicating the wireless communication path to the destination node n8 in the topology table 20 stored in the memory of the source node n4 (hereinafter, path connection information, Or the topology information) is updated (or stored) to the route connection information 21 indicating the route Ra [n4 → n6 → n7 → n8] shown in FIG. 2 (S40). Thus, the memory in the node n4 in which the topology table 20 updated in the path connection information 21 is stored corresponds to the communication path storage means. The first communication path determination process in step S30 not only determines the wireless communication path Ra (see FIG. 1) from the node n4 to the destination node n8, but also other than the node n8. The wireless communication route to the nodes (n1 to 3, n5 to 7) is determined, and the route connection information 22 (see FIG. 2) to the other nodes is updated (or stored) simultaneously with the update of the route connection information 21. Thus, it is desirable to update the entire topology table 20. As described above, the route connection information 22 (see FIG. 2) to the other nodes is also updated at the same time as the route connection information 21 is updated, so that, for example, data transmitted from the node n4 is transferred to the node n8. If it is necessary to transmit data from the node n4 to another node other than the node n8 immediately after the transmission, the topology table 20 is considered to be still highly reliable, and thus updated as described above. By transmitting data according to the wireless communication path shown in the topology table 20, it is possible to reduce the processing time spent on the first communication path determination process (S30) and reduce the processing load.

When the topology table 20 is updated in the step S40, the data to which the route connection information (topology information) 21 representing the route [n4 → n6 → n7 → n8] to the destination node n8 is attached is then displayed. Originated from node n4. Thereby, first, the data transmitted from the node n4 is transmitted to the node n6 of the next node based on the route [n4 → n6 → n7 → n8]. When receiving the data, the relay node n6 that has received the data with the route connection information 21 attached refers to the route connection information 21 attached to the data, and selects the node n7 to which the data is transferred next. Then, the process of transferring the data to the selected node n7 is performed. Similarly, in the relay node n7 that has received the data to which the route connection information 21 is attached, the data is transmitted to the next node n8 selected with reference to the route connection information 21 after receiving the data. Is transferred.
When the data transmitted from the node n4 is received at the destination node n8 in this way, the path [n8 → n7 → n6 → n4] opposite to the path through which the data is transmitted from the node n8. An incoming response signal is transmitted according to When the node n4 that is the data transmission source detects the incoming response signal transmitted from the node n8, it is determined that the data transmission is completed, and the series of processing ends. In the above description, the process of calculating the communication evaluation value by the source node n4 itself is not specifically described. For example, the node n4 itself receives a wireless connection request signal broadcast from the node n4. Thus, the communication evaluation value between the node n4 and another node can be calculated by the communication evaluation value calculation processing procedure of FIG. In addition, a processing example in which the communication evaluation value is calculated by performing the processing of steps S120 to S150 after broadcasting the wireless connection request signal is also conceivable.
In this way, a wireless communication path for transmitting data is determined based on a communication evaluation value related to the performance of direct wireless communication performed directly between nodes as well as the physical distance between nodes. Even when an obstacle is present, a wireless communication path that avoids the obstacle, that is, a wireless communication path having a high communication evaluation value and a high communication quality is determined. As a result, a communication path with good transmission efficiency and the shortest communication time is selected, and as a result, communication efficiency is improved. In addition, unlike conventional systems, it is not necessary to perform data communication between faulty nodes, so that a large amount of communication power is not consumed, power consumption is reduced, and power consumption between wireless terminals is further reduced. The quantity imbalance can be eliminated. The procedure for executing the processing described with reference to the flowcharts of FIGS. 3 and 4 is a wireless communication path routing method which is an example of the first embodiment of the present invention.

<< Second Embodiment >>
Here, a second embodiment of the present invention will be described with reference to FIGS. FIG. 8 is a schematic connection diagram of the ad hoc network X2 showing an example of the wireless communication path determined by the routing method according to the second embodiment, and FIG. 9 is the second communication executed in the source node. It is a flowchart explaining an example of the procedure of a route determination process. In the following description, the same components as those in the first embodiment described above are denoted by the same reference numerals, and the description of the above components is omitted.
Here, the radio network communication system according to the second embodiment of the present invention will be described with reference to the schematic connection diagram of FIG. Here, X2 in FIG. 8 is an ad hoc network configured by wirelessly connecting nodes n1 to n12 (corresponding to a plurality of wireless terminals) so that they can wirelessly communicate with each other. The difference between the configuration of the network X2 and the configuration of the network X1 in the first embodiment described above is that the number of nodes constituting the network is different, and there is no significant difference with respect to the network configuration. Therefore, also in the wireless network communication system according to the second embodiment, each node constituting the network X2 is processed according to a predetermined routing protocol, as in the system of the first embodiment. , The source wireless terminal that transmits data (for example, node n4) directly or indirectly through one or more other wireless terminals (for example, the node for receiving data) n11) is configured as a system for performing wireless communication by wireless connection. In the network X2, in order to simplify the description of the second embodiment, an obstacle 11 (communication inhibition factor) is interposed between the nodes n5 and n11, so that the communication quality is different. It is slightly inferior to other nodes, and is sufficient for transmitting data (text data, etc.) that does not require so high communication quality, but data that requires relatively high communication quality (music or video data or emergency data) It is assumed that the communication environment is insufficient to transmit emergency data that requires data transmission). Further, it is assumed that there is no communication obstruction factor between other nodes except between the nodes n5 and n11, and a communication environment in which good communication quality can be obtained.

Here, with reference to the flowchart of FIG. 9, the procedure of the routing process (including the second communication path determination process) executed by the communication control processor of each node constituting the wireless network communication system used in the network X2. An example will be described. However, in the following description, in order to simplify the description of the processing, the source of data is the node n4, the final destination of the data transmitted from the node n4 is the node n11, and the video transmitted from the node n4 The routing processing of the wireless communication path for transmitting data will be described, but it is not intended to limit the technical scope of the present invention.
In the network X2, as described above, the above-described obstacle 11 that inhibits communication between the nodes n5 and n11 is interposed between the nodes n5 and n11. Further, detailed description of the same procedure as that described with reference to FIG. 3 in the first embodiment is omitted. FIG. 9 is a flowchart for explaining an example of the procedure of the routing process executed at the source node n4.

  When the node n4 is instructed to transmit the data by designating the node n11 as the destination, a wireless connection request signal is transmitted (broadcast) to all nodes existing in the network X2 shown in FIG. (S10), and thereafter, the communication evaluation value transmitted from the node that has received the wireless connection request signal (the data calculated by the communication evaluation value calculation process in FIG. (Data calculated based on this) is set in a reception standby state. Subsequently, in step S20, it is determined whether or not the communication evaluation value transmitted from each node in step S160 of FIG. 4 has been received (communication evaluation value receiving process).

If it is determined in step S20 that the communication evaluation value has been received, a plurality of routes assumed between the source node n4 and the destination node n11, for example, the route R ₁ “n4 → n3 → n5 → n11 ”, R ₂ “ n4 → n3 → n6 → n10 → n11 ”, R ₃ “ n4 → n6 → n10 → n11 ”, etc., and then the determined plurality of routes R ₁ , R ₂ and R ₃ are sorted in descending order of the total value of the communication evaluation values and stored in a storage medium such as a memory of the node n4 that is the transmission source (S21). In the second embodiment, the description will be made assuming that the _three routes R ₁ , R ₂ , and R ₃ are stored in the storage medium in descending order of the total communication evaluation value. It is not a thing.

In the next step S22, first, R _k having the kth highest sum of the communication evaluation values is extracted from the storage medium. That is, at present, the route R ₁ (k = 1) having the highest total communication evaluation value is extracted. Thereafter, in step S23, the communication evaluation values received in all of the above step S20 among the nodes constituting the route R ₁ extracted in step S22, in advance according to the type of data to be transmitted from the node n4 A process (communication evaluation value comparison process) for comparing with a predetermined communication evaluation threshold value is executed. The communication evaluation threshold value is a communication evaluation value indicating a minimum communication quality (communication performance) required for transmitted data. Such a communication evaluation threshold value is stored in advance for each data type in a storage medium such as a memory in a node serving as a transmission source. In step S23, the communication evaluation threshold value corresponding to the moving image data to be transmitted is stored in the memory. The communication evaluation threshold value read from the medium is compared with the communication evaluation value received in step S20.
Here, if it is determined by the communication evaluation value comparison processing that all the communication evaluation values between the nodes received in step S20 are equal to or greater than the communication evaluation threshold (Yes in S23), based on the determination result. The process proceeds to step S30, where the route R ₁ “n4 → n3 → n5 → n11” (see FIG. 8) is determined as a wireless communication route through which data is transmitted between the nodes n4 and n11. After the processes in steps S40 to S70 (see FIG. 3) are performed, a series of routing processes are completed. If it is determined in step S23 that at least one of the received communication evaluation values between the nodes is less than the communication evaluation threshold (No in S23), the process proceeds to step S27.
At step S27, among the plurality of routes route R _k extracted in step S22 is stored in the storage medium, most descending lowest total ranking has been called the communication evaluation values path R by sorting It is determined whether or not _n . If the extracted route R _k is determined to be R _n, that is, if it is determined that there is no route through which data can be transmitted, data communication to the source node n4 is impossible. The notification is output (S29), and then the routing process is terminated without determining the data communication path. On the other hand, in step S27, the route R _k is not a R _n, i.e., low route R _{k + 1} a sum of the communication evaluation values in the following order is judged to be stored in the storage medium than the path R _k Then, in step S28, after the route extracted in step S22 is incremented from route _Rk to route _{Rk + 1} (S28), the process returns to step S22. Thereafter, the above-described processing is repeatedly executed from step S22.
In the second embodiment, between the nodes n5 and n11 constituting the route R ₁ “n4 → n3 → n5 → n11” having the highest total value of the communication evaluation values extracted in step S22. Because the obstacle 11 which becomes a communication hindrance is interposed, the communication environment is insufficient to transmit moving image data which requires a relatively high communication quality. That is, the communication evaluation value between the nodes n5 and n11 is lower than the communication evaluation threshold corresponding to the moving image data to be transmitted. Therefore, the process proceeds from step S27 to step S28 based on the determination in step S23, and then the process from step S22 is repeatedly executed again.
As described above, the processes of steps S22, S23, S27, and S28 are repeatedly performed, so that the above-described node n4 and the destination of the call are received according to the type of data (moving image data in this example) transmitted from the source node n4. Since the wireless communication path through which the data is transmitted is determined with the node n11, the total communication evaluation value is the highest, but communication between certain nodes (in this example, between the nodes n5 and n11). Since the evaluation value is low, the route R ₁ having an inter-node route that cannot be transmitted depending on the data to be transmitted is not determined as a wireless communication route for transmitting data, and the total value of the communication evaluation values is greater than the route R ₁ . since is also low, all routes R ₂ or may transmit video data between nodes of R ₃ is determined as a wireless communication path for transmitting data, a relatively high communication quality is essential Data such as music and videos is, it becomes possible to transmit a communication environment which does not cause problems such interruption or code error data. The procedure for executing the processing described in the flowchart of FIG. 9 is a wireless communication path routing method which is an example of the second embodiment of the present invention.

In the second embodiment described above, the total value of the communication evaluation values is obtained from a plurality of routes sorted and stored in the descending order of the total value of the communication evaluation values in the storage medium such as the memory of the source node n4. A processing example has been described in which a route with a high value is sequentially extracted to determine an optimal wireless communication route that can transmit moving image data. In this case, for example, if it is determined in step S23 that the communication evaluation value between certain nodes (between nodes n5 and n11 in this example) is less than the communication evaluation threshold, the nodes n5 and n11 It is desirable to delete the communication path including a part of the path from the storage medium. Thus, for example, it eliminates the need for wasteful loop process of steps S22 → S23 → S27 → S28 → S22 for different other pathways "n4 → n6 → n5 → n11" is the path R _1, the routing processing It is possible to greatly reduce the processing time consumed.

<< Third Embodiment >>
Next, a third embodiment of the present invention will be described with reference to FIGS. FIG. 10 is a schematic connection diagram of the ad hoc network X2 showing the predetermined radio communication path Rc, and FIG. 11 is an ad hoc example showing the radio communication path determined by the routing method according to the third embodiment of the present invention. 12 is a schematic connection diagram of the network X2, FIG. 12 is a flowchart for explaining another example of the procedure of the second communication path determination process executed at the source node, and FIG. 13 is a communication evaluation value calculation process executed at all nodes. It is a flowchart explaining the other example of the procedure of. In the following description, the same components and the same processing procedures as those of the first and second embodiments described above are denoted by the same reference numerals and the same step numbers, and the description thereof is omitted.
As shown in FIG. 10, before the wireless communication path for transmitting the moving image data transmitted from the source node n4 is secured to the network X2, predetermined data is transmitted from the other node n2 to the node n12. A predetermined wireless communication path Rc “n2 → n3 → n6 → n8 → n12” for transmission exists in the network X2. In this case, in the routing process described in the first and second embodiments, the route Rc is used as a wireless communication route for transmitting the video data transmitted from the source node n4 to the destination node. A route (for example, the routes R ₁ and R _{2 in} FIG. 8) including each node (n2, n3, n6, n8, n12) constituting the node is not determined (selected). In other words, even if the route having a high communication evaluation value is a route that has already been used as a node constituting another wireless communication route Rc, the total value of the communication evaluation value is Another lower path is re-determined and data is transmitted, or transmission of moving image data is waited until data transmission on the path Rc is completed. A process for determining a route according to the data is performed. However, in this case, data that requires real-time characteristics such as moving image data, emergency data that requires urgent data, etc. are transmitted through a route with poor communication quality, resulting in data interruptions or code errors, or a large amount of data transmission. Various inconveniences such as requiring a long time may occur.

  In the third embodiment, in order to solve the above inconvenience, interrupt relay for setting whether to permit relay of data having higher priority than the predetermined data to each node constituting the network X2. A permission setting means is provided. Thereby, for example, even if the nodes n3 and n6 are used as a predetermined route Rc for transmitting predetermined data, the nodes n3 and n6 are connected to the route by the interrupt relay permission setting means. When it is set to permit relaying of data having a higher priority than data transmitted by Rc, the routing configured by the nodes n3 and n6 transmits data by executing a routing process described later. To be determined as a wireless communication path. The interrupt relay permission setting means is achieved by a well-known setting function or the like in the node, and the setting of permission / non-permission of the interrupt relay is performed in the function setting of the routing process.

Here, using the schematic connection diagram of FIG. 11 and the flowcharts of FIG. 12 and FIG. 13, the procedure of the routing process executed by the communication control processor of each node constituting the wireless network communication system used in the network X2 will be described. Another example will be described. Note that detailed description of procedures similar to those described in the first and second embodiments is omitted. However, in the following description, in order to simplify the description of the processing, the data transmitted from the source node n4 to the final destination node n11 is assumed to be moving image data that requires real-time property, and the route of FIG. In Rc, data (text data or the like) that is not particularly critical or requires real-time properties is transmitted. Further, it is assumed that the interrupt relay permission is not set in the node n3 (set to non-permitted), and the interrupt relay permission is set in the node n6.
First, the procedure of the routing process executed by the node n4 will be described using the flowchart of FIG. When the node n4 is instructed to transmit the data by designating the node n11 as a destination, a wireless connection request signal is transmitted (broadcast) to all nodes existing in the network X2 shown in FIG. (S10), and thereafter, the communication evaluation value transmitted from the node that has received the wireless connection request signal (the data calculated by the communication evaluation value calculation process in FIG. (Data calculated based on this) is set in a reception standby state. Subsequently, in step S20, it is determined whether or not the communication evaluation value transmitted from each node in step S160 of FIG. 4 has been received (communication evaluation value receiving process).

Next, the procedure of the communication evaluation value calculation process executed in all the nodes that have received the wireless connection request signal will be described using the flowchart of FIG. The processing procedure from step S110 for receiving the wireless connection request signal transmitted from the node n4 at each node in the network X2 to step S150 for calculating the communication evaluation value is the same as the processing procedure of the flowchart of FIG. It is the same.
When the communication evaluation value is calculated in each node in step S150, it is determined in step S151 whether or not each node is used as a component of the route Rc. This determination is based on, for example, detecting whether or not the own node is included in the route connection information based on the route connection information (information indicating the route Rc) sent from the source node n2. Is done. Here, if it is determined that the node is used for the route Rc, then in step S152, the busy information indicating that the node is used for the route Rc is calculated as the communication evaluation value calculation. It is attached to the communication evaluation value calculated by the process (S150). At this time, it is desirable that data type information indicating the type of data transmitted through the route Rc is also attached to the communication evaluation value. Thereafter, the process proceeds to step S153. If it is determined in step S151 that the node is not used for the route Rc, the process proceeds to step S160, and only the calculated communication evaluation value (data indicating) is the node from which the moving image data is transmitted. It is transmitted to n4 (communication evaluation value transmission process).

  When the process proceeds to step S153, it is determined in this step S151 whether permission for data relay interruption is set in the node being used for the route Rc in step S151 (S153). If it is determined that it has been made, then in step S154, interrupt permission information (corresponding to the setting state) indicating that data relay interruption is permitted is attached to the calculated communication evaluation value, and the above-mentioned In step S160, the communication evaluation value to which the in-use information and the interrupt permission information are attached is transmitted to the node n4. If it is determined in step S153 that the permission setting has not been made, the process proceeds to step S160, and the communication evaluation value to which only the in-use information is attached is transmitted to the node n4. In this way, by transmitting the communication evaluation value to which the busy information and the interrupt permission information are attached to the source node n4, the node n4 that has received the communication evaluation value receives step S24 described below. ~ 26 determination processes are possible.

On the node n4 side, the communication evaluation value comparison process from step S20 to step S23 for determining whether or not the communication evaluation value transmitted in step S160 in FIG. 13 has been received is performed, as in the second embodiment. Executed. If it is determined by the communication evaluation value comparison process in step S23 that all the communication evaluation values between the nodes received in step S20 are equal to or greater than the communication evaluation threshold value (Yes side in S23), then the process is step. Proceed to S24.
Subsequently, in step S24, it is determined whether or not the route (for example, route R ₁ “n4 → n3 → n5 → n11”) determined to be equal to or higher than the communication evaluation threshold in step S23 is used for the predetermined route Rc. Is done. This determination is made based on whether or not the in-use information attached in step S152 is included in the received communication evaluation value. If it is determined that the in-use information is included, the process proceeds to step S25. If it is determined that the in-use information is not included, the process proceeds to step S30, and the second communication path determination process described above is performed. Since the route R ₁ includes the node n3 that constitutes the route Rc, the process of step S24 proceeds to the Yes side.

  When the process proceeds to step S25, here, a process of comparing the priority of data transmitted from the node n4 and data transmitted from the node n3 (data priority comparison process) is executed. The priority of the data is, for example, a priority coefficient (weighting coefficient) is defined in advance according to the type of data, and the degree of whether data is preferentially relayed according to the size of this coefficient. It is an indicator. Specifically, the priority coefficient of highly important data such as urgent data and moving image data is set large, and the priority coefficient of low importance data such as text data is set small. The source node stores data and the like in a table indicating the priority according to the type of data, and the data priority comparison process is performed by reading and referring to the data. Realized. The data transmitted through the route Rc is recognized by referring to the data type information included in the communication evaluation value transmitted from the node n3. Now, since the data transmitted by the Rc is text data and the data transmitted from the node n4 is moving image data, the processing in step S25 proceeds to the Yes side. If it is determined that the priority of the data transmitted from the node n4 is low, the process proceeds to step S27.

  Subsequently, when the process proceeds to step S26, it is determined here whether or not an interrupt permission setting has been made for the node n3. This determination is made based on whether or not the interrupt evaluation information attached in step S154 is included in the communication evaluation value transmitted from the node n3. If it is determined that the interrupt permission information is included, the process proceeds to step S30. However, since the interrupt relay permission is not set for the node n3 as described above, the process proceeds to step S30. Proceeding to S27, after the processing of step S27 and step S28 is performed, the processing from step S22 is repeated.

When the process returns to step S22, where, for example, the route R ₃ "n4 → n6 → n10 → n11" is extracted, then the total value of the communication evaluation values of the route R ₃ is more communication rating threshold in step S23 If it is determined that the interrupt relay permission is set for the node n6 constituting the route Rc, all the determination processes in the next steps S24, S25, and S26 proceed to the Yes side, and then the steps S30 to S30 are performed. The process of S70 is executed. In this manner, a wireless communication path through which the moving image data is transmitted between the source node n4 and the destination node n11 is determined according to the interrupt relay permission setting state transmitted from each node. Therefore, the relay terminal is forcibly opened against the intention of the user of the relay terminal or the user of the terminal device of the transmission source by urgent data etc. being always given priority and the wireless communication path is determined Thus, a wireless network communication system with higher utility value can be realized without losing the convenience of the user.

<< Fourth Embodiment >>
Further, the processing in step S30 described with reference to the flowchart of FIG. 3 in the first embodiment described above is performed between the source node n4 and the destination node n8 based on the received communication evaluation value. 1 is a process of determining a route Ra “n4 → n6 → n7 → n8” (see FIG. 1) having the highest total communication evaluation value as a wireless communication route through which data is transmitted. However, even if the route Ra is determined by this process, for example, if a communication error such as communication failure or communication disconnection occurs during data transmission on the route Ra, the routing according to the flowchart of FIG. Processing must be done. In order to eliminate such inconvenience, a plurality of routes assumed between the node n4 and the destination node n8, for example, “n4 → n3 → n8”, “n4 → n3 → n7 → n8”, “ n4.fwdarw.n6.fwdarw.n7.fwdarw.8 ", etc., and at least until the data is normally transmitted to the destination node, that is, until the data transmission is completed, When a plurality of routes are stored in a storage medium such as a memory and a communication error or the like occurs in the route Ra, the route Ra can be changed from other routes except the route Ra stored in the storage medium. Next, an embodiment may be considered in which a route having a high total communication evaluation value is determined (extracted) as a wireless communication route used for data transmission. The communication error or the like is detected based on the field intensity value of the radio wave at the time of data transmission at each node that relays data or the node that is the data source. For example, it is conceivable to determine whether or not there is a communication error based on whether or not the electric field strength value is less than a predetermined value. In such an embodiment, it is not necessary to execute the first communication route determination process again, the time spent for the process is reduced, the processing load is reduced, and the data transmission efficiency when a communication error occurs is improved. Can be improved. In this embodiment, it is preferable to sort and store the plurality of routes in descending order of the total value of the communication evaluation values.

<< Fifth Embodiment >>
In the above-described first to third embodiments, the process of step S150 described with reference to the flowchart of FIG. 4 or FIG. 13 is based on the wireless communication conditions predetermined in each node existing in the network X1 or X2. A communication evaluation value related to the performance of direct wireless communication performed with a satisfying node may be calculated. As the wireless communication conditions, for example, the separation distance between the nodes is within a predetermined separation distance, the electric field strength value of the received radio wave between the nodes is greater than a predetermined value, or the number of relays (hops) The number of times) is within a predetermined number of times, or the communication speed between nodes is higher than a predetermined speed. Since it is rare to perform wireless communication directly with a wireless terminal that does not satisfy such wireless communication conditions, in other words, frequent wireless communication is performed only between wireless terminals that satisfy the wireless communication condition (for example, adjacent wireless terminals). Therefore, it is considered sufficient to calculate the communication evaluation value of direct wireless communication performed with another wireless terminal that satisfies the wireless communication condition. In such an embodiment, the burden of processing for calculating a communication evaluation value with a wireless terminal outside the wireless communication conditions is reduced, and the time spent for such processing is drastically reduced.

<< Sixth Embodiment >>
In the first to third embodiments described above, the data relating to the received electric field strength, the remaining battery level, the wireless communication speed, etc., that is, the information relating to the communication capability is the wireless connection request transmitted from the node n4. The signal has been described as being measured or received after being received at each node in the network X1. However, the present invention is not limited to this. For example, the signal is periodically measured or received every predetermined time. It may be. Thus, since the communication evaluation value is periodically calculated, the data transmission source node n4 can immediately determine the wireless communication path based on the communication evaluation value when transmitting data. After the data transmission operation is performed at the original node n4, data can be transmitted relatively early.

The schematic connection diagram of the ad hoc network X1 which shows the radio | wireless communication path | route Ra determined by the routing method which concerns on the 1st Embodiment of this invention. The table figure which shows the topology information of the radio | wireless communication path | route determined based on the communication evaluation value between nodes. The flowchart explaining an example of the procedure of the communication route determination process performed in the node of a transmission origin. The flowchart explaining an example of the procedure of the communication evaluation value calculation process performed in all the nodes. The schematic connection diagram of the ad hoc network X which shows the radio | wireless communication path | route determined by the conventional routing method. The table figure which shows the topology information of the radio | wireless communication path | route determined based on the physical distance between nodes. The table figure which shows the physical linear distance between each node. The schematic connection diagram of the ad hoc network X2 which shows an example of the radio | wireless communication path determined by the routing method which concerns on 2nd Embodiment. The flowchart explaining an example of the procedure of the 2nd communication path determination process performed in the node of a transmission origin. The schematic connection diagram of the ad hoc network X2 which shows predetermined | prescribed radio | wireless communication path | route Rc. The schematic connection diagram of the ad hoc network X2 which shows an example of the radio | wireless communication path determined by the routing method which concerns on the 3rd Embodiment of this invention. The flowchart explaining the other example of the procedure of the 2nd communication path determination process performed in the node of a transmission origin. The flowchart explaining the other example of the procedure of the communication evaluation value calculation process performed in all the nodes.

Explanation of symbols

X ... Ad hoc network (independent and distributed wireless network)
n1-n12 ... Node (an example of a wireless terminal)
Ra, Rb, Rc, R ₁ , R ₂ , R ₃ ... Wireless communication paths 10 and 11.
20 ... Topology table

Claims (21)

A wireless network communication system used in an autonomous distributed wireless network configured by wirelessly connecting a plurality of wireless terminals so that they can perform wireless communication with each other. Or a wireless network communication system for performing wireless communication by relaying one or more other wireless terminals and indirectly connecting to the wireless terminal that is the destination of the data,
Each of the plurality of wireless terminals
Communication capability information acquisition means for acquiring information on two or more communication capabilities of direct wireless communication performed with all other wireless terminals that are directly wirelessly connected to the wireless terminal;
A relay side communication evaluation value calculating means for calculating a communication evaluation value related to the performance of the direct wireless communication based on the information related to the communication capability acquired by the communication capability information acquiring means;
A wireless network communication system comprising: Each of the plurality of wireless terminals
A communication evaluation value transmitting means for transmitting the communication evaluation value calculated by the relay-side communication evaluation value calculating means to the wireless terminal as the transmission source;
The source wireless terminal is
Communication evaluation value receiving means for receiving the communication evaluation value transmitted by the communication evaluation value transmitting means;
Based on the communication evaluation value received by the communication evaluation value receiving means, a first wireless communication path for transmitting the data between the source wireless terminal and the destination wireless terminal is determined. A communication path determination means;
The wireless network communication system according to claim 1, comprising:   The first communication path determining means determines a wireless communication path through which the data is transmitted from a plurality of wireless communication paths determined based on the communication evaluation value received by the communication evaluation value receiving means. The wireless network communication system according to claim 1 or 2. A wireless network communication system used in an autonomous distributed wireless network configured by wirelessly connecting a plurality of wireless terminals so that they can perform wireless communication with each other. Or a wireless network communication system for performing wireless communication by relaying one or more other wireless terminals and indirectly connecting to the wireless terminal that is the destination of the data,
Each of the plurality of wireless terminals
Communication capability information acquisition means for acquiring information on two or more communication capabilities of direct wireless communication performed with all other wireless terminals that are directly wirelessly connected to the wireless terminal;
Comprising communication capability information transmitting means for transmitting information related to the communication capability acquired by the communication capability information acquiring means to the wireless terminal that is the transmission source;
The source wireless terminal is
Communication capability information receiving means for receiving information on the communication capability transmitted by the communication capability information transmitting means;
A caller-side communication evaluation value calculating means for calculating a communication evaluation value related to the performance of the direct wireless communication based on the information related to the communication capability received by the communication capability information receiving means;
A wireless network communication system comprising: A wireless network communication system used in an autonomous distributed wireless network configured by wirelessly connecting a plurality of wireless terminals so that they can perform wireless communication with each other. Or a wireless network communication system for performing wireless communication by relaying one or more other wireless terminals and indirectly connecting to the wireless terminal that is the destination of the data,
The source wireless terminal is
A second communication path determining means for determining a wireless communication path for transmitting the data between the source wireless terminal and the destination wireless terminal according to the type of the transmitted data; A wireless network communication system. Each of the plurality of wireless terminals
Communication capability information acquisition means for acquiring information on two or more communication capabilities of direct wireless communication performed with all other wireless terminals that are directly wirelessly connected to the wireless terminal;
A relay side communication evaluation value calculating means for calculating a communication evaluation value related to the performance of the direct wireless communication based on the information related to the communication capability acquired by the communication capability information acquiring means;
Communication evaluation value transmitting means for transmitting the communication evaluation value calculated by the relay side communication evaluation value calculating means to the wireless terminal that is the transmission source,
The source wireless terminal is
Communication evaluation value receiving means for receiving the communication evaluation value transmitted by the communication evaluation value transmitting means;
A communication evaluation value comparing means for comparing a communication evaluation threshold related to the performance of the direct wireless communication determined in advance according to the type of data to be transmitted and the communication evaluation value received by the communication evaluation value receiving means; Further comprising
The second communication path determining means determines a wireless communication path through which the data is transmitted between the source wireless terminal and the destination wireless terminal based on the comparison result by the communication evaluation value comparing means. The wireless network communication system according to claim 5. Each of the plurality of wireless terminals
Interrupt relay permission setting means for setting whether to permit relaying of data having higher priority than the predetermined data when the wireless terminal constitutes a predetermined wireless communication path for transmitting the predetermined data;
Further comprising: setting state transmitting means for transmitting the setting state by the interrupt relay permission setting means to the terminal device of the transmission source,
The source wireless terminal is
Setting state receiving means for receiving the setting state transmitted by the setting state transmitting means;
The second communication path determination unit is a wireless unit that transmits the data between the source wireless terminal and the destination wireless terminal according to the setting state received by the setting state receiving unit. The wireless network communication system according to claim 5 or 6, wherein a communication path is determined. A communication path storage means for storing the wireless communication path determined by the first communication path determination means and / or the second communication path determination means;
Data transmission means for transmitting the data based on the wireless communication path stored in the communication path storage means;
The wireless network communication system according to claim 1, further comprising:   The communication capability information acquisition means receives information on the communication capability after the plurality of wireless terminals receive wireless connection request signals transmitted to the plurality of wireless terminals in the wireless network by the source wireless terminal. The wireless network communication system according to claim 1, which is to be acquired.   The communication capability information acquisition means acquires information on two or more communication capabilities of the direct wireless communication performed with other wireless terminals that satisfy a predetermined wireless communication condition at the plurality of wireless terminals. A wireless network communication system according to any one of claims 1 to 9.   The relay-side communication evaluation value calculation means or the transmission-side communication evaluation value calculation means periodically calculates the communication evaluation value based on the information on the communication capability periodically acquired by the communication capability information acquisition unit. The wireless network communication system according to claim 1.   The communication evaluation value transmitting means, after the plurality of wireless terminals receive the wireless connection request signal transmitted by the source wireless terminal, transmits the communication evaluation value together with a response signal of the received wireless connection request signal. The wireless network communication system according to claim 1, wherein the wireless network communication system transmits data to the wireless terminal that is the transmission source.   The wireless network communication system according to any one of claims 1 to 12, wherein the communication capability of the direct wireless communication is a wireless communication speed, a received electric field strength of a wireless radio wave, a remaining power amount of the wireless terminal, and position information of the wireless terminal. . A plurality of wireless terminals constituting a self-distributed wireless network by being wirelessly connected to each other, relaying data transmitted from a wireless terminal that originated by wireless communication via the wireless network, and the data In a relay wireless terminal that forwards to a destination wireless terminal,
Communication capability information for acquiring information on two or more communication capabilities of direct wireless communication performed between the relay wireless terminal and all other wireless terminals in the wireless network directly connected to the relay wireless terminal Acquisition means;
A relay side communication evaluation value calculating means for calculating a communication evaluation value related to the performance of the direct wireless communication based on the information related to the communication capacity acquired by the communication capability information acquiring means;
A relay wireless terminal comprising:   The relay wireless terminal according to claim 14, further comprising a communication evaluation value transmitting unit that transmits the communication evaluation value calculated by the relay side communication evaluation value calculating unit to the transmitting wireless terminal. Interrupt relay permission setting means for setting whether to permit relaying of data having higher priority than the predetermined data when the wireless terminal constitutes a predetermined wireless communication path for transmitting the predetermined data;
The relay wireless terminal according to claim 14 or 15, further comprising setting state transmission means for transmitting a setting state by the interrupt relay permission setting means to the terminal device of the transmission source. A plurality of wireless terminals constituting an autonomous distributed wireless network by being wirelessly connected to each other and relaying directly or with one or more other wireless terminals to a destination wireless terminal of outgoing data In the wireless terminal that is the source of the data that performs wireless communication via the wireless network by indirectly connecting to the wireless network,
Communication evaluation value receiving means for receiving a predetermined communication evaluation value transmitted from the one or more other wireless terminals;
Based on the communication evaluation value received by the communication evaluation value receiving means, one or more wireless communication paths through which the data is transmitted between the source wireless terminal and the destination wireless terminal are First communication path determination means for determining;
A wireless terminal as a transmission source, comprising: A plurality of wireless terminals constituting an autonomous distributed wireless network by being wirelessly connected to each other and relaying directly or with one or more other wireless terminals to a destination wireless terminal of outgoing data In the wireless terminal that is the source of the data that performs wireless communication via the wireless network by indirectly connecting to the wireless network,
Communication capability information receiving means for receiving information on the predetermined communication capability transmitted by the communication capability information transmitting means possessed by the plurality of wireless terminals;
Based on the information on the communication capability received by the communication capability information receiving means, it relates to the performance of direct wireless communication performed between the plurality of wireless terminals and all other wireless terminals that are directly wirelessly connected. A transmission side communication evaluation value calculating means for calculating a communication evaluation value;
A wireless terminal as a transmission source, comprising: A plurality of wireless terminals constituting an autonomous distributed wireless network by being wirelessly connected to each other and relaying directly or with one or more other wireless terminals to a destination wireless terminal of outgoing data In the wireless terminal that is the source of the data that performs wireless communication via the wireless network by indirectly connecting to the wireless network,
A second communication path determining means for determining a wireless communication path for transmitting the data between the source wireless terminal and the destination wireless terminal according to the type of the transmitted data; A wireless terminal that is a source of transmission. A wireless communication path for data transmitted in an autonomous distributed wireless network configured by wireless connection of a plurality of wireless terminals so that they can perform wireless communication with each other, formed by relaying one or more wireless terminals In the above-described routing method of the wireless communication path,
A communication capability information acquisition step of acquiring information on two or more communication capabilities of direct wireless communication performed with all other wireless terminals directly connected to the wireless terminal;
A communication evaluation value calculating step for calculating a communication evaluation value regarding the performance of the direct wireless communication based on the information regarding the communication capability acquired by the communication capability information acquiring step;
A first communication path determining step for determining a wireless communication path of data transmitted in the wireless network based on the communication evaluation value calculated by the communication evaluation value calculating step;
A method for routing a wireless communication path, comprising: A wireless communication path for data transmitted in an autonomous distributed wireless network configured by wireless connection of a plurality of wireless terminals so that they can perform wireless communication with each other, formed by relaying one or more wireless terminals In the above-described routing method of the wireless communication path,
A communication capability information acquisition step of acquiring information on two or more communication capabilities of direct wireless communication performed with all other wireless terminals directly connected to the wireless terminal;
A communication evaluation value calculating step for calculating a communication evaluation value regarding the performance of the direct wireless communication based on the information regarding the communication capability acquired by the communication capability information acquiring step;
A communication evaluation value comparison step for comparing the communication evaluation threshold relating to the performance of the direct wireless communication determined in advance according to the type of the data to be transmitted, and the communication evaluation value calculated by the communication evaluation value calculation step;
A second communication path determination step for determining a wireless communication path through which the data is transmitted between the source wireless terminal and the destination wireless terminal based on the comparison result of the communication evaluation value comparison step;
A method for routing a wireless communication path, comprising:

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