JP2007235895A - Wireless device and radio communication network fabricated therewith - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wireless device capable of suppressing a network load and obtaining a high throughput constantly. <P>SOLUTION: Wireless devices 1 to 8 detect their own longitude λ and latitude ϕ by D-GPS receivers, calculate their own positions based on the detected longitude λ and latitude ϕ and then receive "n" wireless device positions from adjacent "n" wireless devices. Additionally, each of the wireless devices 1 to 8 calculates "n" distances between the own device and "n" wireless devices based on the positions of own device and "n" wireless devices. Each of the wireless devices 1 to 8 also receives "k" distances between adjacent wireless devices among multiple wireless comprising "m" wireless devices and "n" wireless devices positioned with two hops or more from a wireless device adjacent to the own device. In this way, each of the wireless devices 1 to 8 performs radio communication via a route determined based on the received "n" distances and "k" distances and with a relatively large stability. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a wireless device and a wireless communication network including the wireless device, and more particularly to a wireless device constituting an ad hoc network system constructed autonomously and instantaneously and a wireless communication network including the wireless device.

  An ad hoc network is a network that is autonomously and instantaneously constructed by a plurality of wireless devices communicating with each other. In an ad hoc network, when two wireless devices that communicate with each other do not exist in the communication area, a wireless device located between the two wireless devices functions as a router and relays a data packet. Can be formed.

  Such an ad hoc network is about to be applied to various fields such as a wireless communication network in a stricken area and streaming in ITS (Intelligent Transport Systems) inter-vehicle communication (Non-Patent Document 1).

  Dynamic routing protocols that support multi-hop communication include table-driven protocols and on-demand protocols. The table-driven protocol periodically exchanges control information related to a route and constructs a route table in advance, and includes GSR (Global State Routing), FSR (Fish-eye State Routing), OLSR (Optimized Link). State Routing) and DSDV (Destination Sequential Distance Vector) are known.

  In addition, the on-demand protocol is a method for constructing a route to a destination for the first time when a data transmission request occurs, and includes DSR (Dynamic Source Routing) and AODV (Ad Hoc On-Demand Distance Vector Routing). Are known.

In a conventional ad hoc network, when data communication is performed from a transmission source to a transmission destination, a route is determined so that the number of hops from the transmission source to the transmission destination is as small as possible (Non-Patent Document 2).
Masahiro Watanabe “Wireless Ad Hoc Network”, Automobile Engineering Society Spring Meeting Humantronics Forum, pp 18-23, Yokohama, May 2003. Guangyu Pei, at al, “Fisheye state routing: a routing scheme for ad hoc wireless networks”, ICC2000. Commun., Volume 1, pp70-74, LA, June 2000.

  However, in the conventional ad hoc network, the route to the transmission destination is determined so that the number of hops is minimized. Therefore, when the route to the transmission destination includes a route with low received signal strength, the route is stable. Therefore, it is difficult to perform wireless communication, and there is a problem that the throughput of wireless communication is reduced.

  In order to solve this problem, a plurality of GPS (Global Positioning System) data indicating the positions of a plurality of wireless devices constituting an ad hoc network are shared by a plurality of wireless devices, and each of them is based on the plurality of shared GPS data. It is conceivable that the wireless device determines the wireless communication route so that the total position of the plurality of wireless devices is grasped and the communication distance to the transmission destination is shortened.

  However, in such a method, in order to share the positions of a plurality of wireless devices between the plurality of wireless devices, each wireless device needs to repeatedly transmit the measured GPS data to other wireless devices. There is a problem that the load on the network increases.

  Therefore, the present invention has been made to solve such a problem, and an object of the present invention is to provide a radio apparatus that can suppress a load on a network and stably obtain a high throughput.

  Another object of the present invention is to provide a wireless communication network including a wireless device that can suppress a load on the network and stably obtain a high throughput.

  According to the present invention, a wireless device is a wireless device that is autonomously established and constitutes a wireless communication network in which wireless communication is performed between a transmission source and a transmission destination, and includes a position detection unit, a reception unit, , Distance calculating means and communication means. The position detecting means detects first position information indicating the position of the wireless device. The receiving unit receives n pieces of second position information indicating the positions of n (n is a positive integer) adjacent wireless devices adjacent to the wireless device from the n adjacent wireless devices. The distance calculation means calculates n distances between the wireless device and n adjacent wireless devices based on the first position information and the n second position information. The communication means performs wireless communication along a suitable path that is determined based on k (k is a positive integer) distance and n distances and that has a relatively high degree of stability. Each of the k distances is m (m is a positive integer) number of wireless devices and n pieces of wireless devices capable of wireless communication with the wireless device using any one of the adjacent wireless devices as a repeater. This is a distance between two adjacent wireless devices in a plurality of wireless devices composed of adjacent wireless devices.

  Preferably, a suitable route is determined based on k + n route stability indicators. Each of the k + n route stability indices indicates the degree of stability of the route, and is calculated based on each of the k distances or each of the n distances.

  Preferably, the wireless device further includes route index calculation means and route determination means. The route index calculation means calculates n route stability indexes based on the n distances. The route determination means determines a route having a minimum sum of the route stability indexes to the transmission destination as a preferable route based on the k + n route stability indexes. Then, the receiving means further receives k route stability indicators from at least one of the n adjacent wireless devices, and outputs the received k route stability indicators to the route determining means. The communication means performs wireless communication along a suitable route determined by the route determination means.

  Preferably, a preferable route is a route having a minimum total route stability index that is a total sum of route stability levels when a route request packet for requesting establishment of a route from the transmission source to the transmission destination is transmitted to the transmission destination. Become.

  Preferably, when the wireless device is a repeater that relays wireless communication between a transmission source and a transmission destination, when the wireless device receives a route request packet, the communication device stabilizes the total route stability included in the received route request packet. The index is updated and relayed, and the route response packet, which is a response to the route request packet, is relayed along a suitable route to the wireless device existing on the transmission source or the transmission source side.

  According to the invention, the wireless communication network is a wireless communication network that is autonomously established and performs wireless communication between a transmission source and a transmission destination, and includes a plurality of wireless devices. The plurality of wireless devices include the wireless device according to any one of claims 1 to 5.

  In the present invention, each wireless device constituting the wireless communication network receives position information of n wireless devices from n wireless devices adjacent to the wireless device, and receives the received position information of the n wireless devices. Based on the position information of itself, n distances between itself and n wireless devices are calculated. Each wireless device constituting the wireless communication network is adjacent to each other in a plurality of wireless devices including n distances, n wireless devices, and m wireless devices existing at a position of 2 hops or more from itself. Wireless communication is performed along a suitable route that is determined based on m distances between wireless devices and has a relatively high degree of stability.

  Therefore, according to the present invention, the location information of each wireless device is transmitted / received between the wireless devices for route determination, and stable wireless communication can be performed while suppressing the load on the wireless communication network. it can. That is, it is possible to stably obtain a high throughput by suppressing the load on the wireless communication network.

  Embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

  FIG. 1 is a schematic diagram of a radio communication net arc according to an embodiment of the present invention. The wireless communication net arc 10 includes wireless devices 1 to 8. The wireless devices 1 to 8 are arranged in a wireless communication space and autonomously configure a network. When transmitting data from the wireless device 1 to the wireless device 3, the wireless devices 2, 4 to 8 relay the data from the wireless device 1 and deliver it to the wireless device 3.

  In this case, the wireless device 1 can perform wireless communication with the wireless device 3 via four different paths. That is, the wireless device 1 can perform wireless communication with the wireless device 3 through the wireless devices 4 and 7 and can perform wireless communication with the wireless device 3 through the wireless devices 2 and 7. In addition, wireless communication can be performed with the wireless device 3 via the wireless devices 5 and 6, and wireless communication can be performed with the wireless communication 3 via the wireless device 8.

  When wireless communication is performed via the wireless device 8, the number of hops is relatively small as “2”, and when wireless communication is performed via the wireless devices 4, 7, the wireless devices 2, 7, and the wireless devices 5, 6, The number of hops is relatively large as “3”.

  Accordingly, when a route for performing wireless communication via the wireless device 8 is selected, the number of hops is relatively reduced to “2”. Therefore, generally, the throughput of wireless communication from the wireless device 1 to the wireless device 3 is low. Get higher.

  However, when the received signal strength between the wireless device 1 and the wireless device 8 is weak, the throughput of wireless communication between the wireless device 1 and the wireless device 8 decreases, so if a route with a small number of hops is selected, The throughput is not high.

  Therefore, in the following, a method for establishing a path between a transmission source and a transmission destination so as to reduce the load on the wireless communication network 10 and to stably increase the wireless communication throughput will be described.

[Embodiment 1]
In the first embodiment, the FSR protocol is basically used as a protocol for establishing a path between a transmission source and a transmission destination. This FSR protocol is a table-driven routing protocol, and exchanges route information with a relatively close wireless device and exchanges route information with a distant wireless device. It is a protocol that reduces the traffic load by reducing.

  FIG. 2 is a schematic block diagram in the first embodiment showing the configuration of radio apparatus 1 shown in FIG. The wireless device 1 includes a wireless LAN (Local Area Network) terminal 11, an array antenna 12, cables 13, 17, and 20, a D-GPS (Differential-Global Positioning System) receiver 14, a GPS antenna 15, and an FM. An antenna 16, an operation device 18, and a maintenance device 19 are provided.

  The wireless LAN terminal 11 has a GPS driver unit 110. In the wireless LAN terminal 11, the GPS driver unit 110 is connected to the D-GPS receiver 14 via the cable 13, connected to the operation device 18 and the maintenance device 19 via the cable 17, and maintained via the cable 20. Connected to device 19.

  The GPS driver unit 110 of the wireless LAN terminal 11 controls the D-GPS receiver 14 via the cable 13 and receives the GPS data acquired by the D-GPS receiver 14 via the cable 13.

  Further, when the wireless LAN terminal 11 receives from the other wireless device the wireless frame RFF including the position information of the other wireless device acquired by the other wireless device, the wireless LAN terminal 11 transmits the received wireless frame RFF to the wired frame by a method described later. The WIRF is converted and transmitted to the controller device 18.

  Further, the wireless LAN terminal 11 transmits and receives signals by controlling the array antenna 12 so as to emit a non-directional beam or a directional beam.

Further, the wireless LAN terminal 11 receives an acquisition request signal D _GPS requesting acquisition of GPS data from the operation device 18 via the cable 17. Then, the wireless LAN terminal 11 outputs the GPS data to the operation device 18 via the cable 17 in accordance with the GPS data acquisition request signal _DGPS .

  The array antenna 12 transmits and receives signals using an omnidirectional beam pattern or a directional beam pattern. The cable 13 is made of RS-232-G, and connects the D-GPS receiver 14 to the GPS driver unit 110 of the wireless LAN terminal 11.

  The D-GPS receiver 14 includes a GPS antenna 15 and an FM antenna 16. The D-GPS receiver 14 measures the longitude and latitude and speed of the wireless device 1 via the GPS antenna 15 and receives differential information from the D-GPS station (not shown) via the FM antenna 16. Then, the D-GPS receiver 14 corrects the measured longitude and latitude using the differential information, and transmits the corrected longitude and latitude to the GPS driver unit 110 via the cable 13 as GPS data.

  The GPS antenna 15 receives the longitude and latitude transmitted from a satellite (not shown) and outputs it to the D-GPS receiver 14. The FM antenna 16 receives the differential information from the D-GPS station and outputs it to the D-GPS receiver 14.

  The cable 17 is a cable having a twisted pair structure in accordance with Fast Ethernet (“Ethernet” is a registered trademark) standard, and connects the wireless LAN terminal 11 to the operation device 18 and the maintenance device 19.

  The operating device 18 receives the radio frame RFF from the wireless LAN terminal 11 via the cable 17.

Further, the controller device 18 transmits an acquisition request signal D _GPS requesting acquisition of GPS data to the wireless LAN terminal 11 via the cable 17 and receives GPS data from the wireless LAN terminal 11 via the cable 17.

  Then, the controller device 18 includes position information (position information acquired by the wireless devices 2 to 8 adjacent to the wireless device 1) included in the wireless frame RFF and GPS data (wireless device) received from the wireless LAN terminal 11. 1), the distances r12, r14, r15, r18 between the wireless device 1 and the wireless devices 2, 4, 5, 8 are calculated by the method described later, and the calculation is performed. The distance is converted into a link metric indicating the degree of stability of the route by a method described later.

  Further, the controller device 18 uses the converted link metric and the path information for each transmission destination included in the radio frame RFF from the radio devices 2, 4, 5 and 8 by the method described later. A routing table for the transmission destination is created, and an optimal route for wireless communication to the transmission destination wireless device 3 is determined based on the created routing table.

  The maintenance device 19 receives GPS data from the wireless LAN terminal 11 via the cable 17 and maintains the wireless LAN terminal 11 via the cable 20 based on the received GPS data. More specifically, the maintenance device 19 controls the wireless LAN terminal 11 so that it exists at a position indicated by the GPS data and moves at a speed indicated by the GPS data.

  FIG. 3 is a schematic diagram illustrating the configuration of the wireless LAN terminal 11, the array antenna 12, and the operation device 18 illustrated in FIG. The wireless LAN terminal 11 includes a lower layer of an ARPA (Advanced Research Projects Agency) Internet hierarchical structure. That is, the wireless LAN terminal 11 includes a GPS driver unit 110, an antenna control module 111, a wireless interface module 112, a MAC (Media Access Control) module 113, an address conversion table 114, and an LLC (Logical Link Control) module 115. And a wired interface 116.

  The array antenna 12 includes antenna elements 121 to 127 and varactor diodes 131 to 136. The antenna elements 121 to 126 are parasitic elements, and the antenna element 127 is a feed element. The antenna elements 121 to 127 are arranged substantially perpendicular to the xy plane of xyz orthogonal coordinates, that is, substantially parallel to the z axis.

  Varactor diodes 131 to 136 are connected between antenna elements 121 to 126 and a ground node, respectively. Thereby, the varactor diodes 131 to 136 which are variable capacitance elements are loaded on the antenna elements 121 to 126 which are parasitic elements, respectively.

  As described above, the array antenna 12 includes one feeding element (antenna element 127) and six parasitic elements (antenna elements 121 to 126).

  The operation device 18 includes, for example, a personal computer (PC) and includes an input unit 181, a display unit 182, an e-mail application 183, and a communication control unit 184.

  The communication control unit 184 includes an upper layer of the ARPA Internet hierarchical structure. That is, the communication control unit 184 includes a wired interface 185, an IP (Internet Protocol) module 186, a routing table 187, a TCP module 188, a UDP module 189, a routing daemon 190, and an SMTP (Simple Mail Transfer Protocol) module. 191.

  The GPS driver unit 110 of the wireless LAN terminal 11 belongs to the physical layer. The function of the GPS driver unit 110 is as described above. The GPS driver unit 110 transmits the GPS data received from the D-GPS receiver 14 to the routing daemon 190 of the controller device 18 via the cable 17.

  The antenna control module 111 supplies control voltage sets CLV0 to CLV12 to the varactor diodes 131 to 136 of the array antenna 12 to switch the beam pattern of the array antenna 12 to an omnidirectional beam pattern or a directional beam pattern.

  The wireless interface module 112 belongs to the physical layer and is connected to the antenna element 127 (feeding element) of the array antenna 12. Then, the wireless interface module 112 modulates and converts the frequency of the wired frame WIRF or the wireless frame RFF received from the MAC module 113 in accordance with a predetermined rule, and supplies the modulated signal to the antenna element 127 (feeding element) of the array antenna 12. The wired frame WIRF or the radio frame RFF received from the 12 antenna elements 127 is demodulated and frequency-converted according to a predetermined rule, and transmitted to the MAC module 113. The wired frame WIRF is a frame corresponding to Ethernet (registered trademark) (hereinafter the same).

  The wireless interface module 112 detects the received signal strength when the array antenna 12 receives a signal, and outputs the detected received signal strength to the routing daemon 190 of the controller device 18 via the wired interface 116 and the cable 17. To do.

  The MAC module 113 belongs to the MAC layer and receives the wired frame WIRF from the controller device 18. Then, when the destination MAC address included in the wired frame WIRF is a broadcast address, the MAC module 113 broadcasts the wired frame WIRF as it is. When the destination MAC address of the wired frame WIRF is a multicast address, the MAC module 113 directly uses the wired frame WIRF as it is. Multicast.

  Further, when the destination MAC address of the wired frame WIRF is the transmission destination wireless device (any one of the wireless devices 2 to 8), the MAC module 113 converts the wired frame WIRF into the wireless frame RFF by a method described later. Then, the MAC module 113 transmits the radio frame RFF to the wireless LAN terminal 11 of the transmission destination wireless device via the array antenna 12.

  Further, when receiving the wired frame WIRF from the wireless interface module 112, the MAC module 113 transmits the received wired frame WIRF to the LLC module 115, and when receiving the wireless frame RFF from the wireless interface module 112, the received wireless frame. The RFF is converted into a wired frame WIRF by a method described later and transmitted to the LLC module 115.

  Further, the MAC module 113 executes a MAC protocol and performs retransmission control of data (frames). The MAC module 113 detects that the link has been disconnected when the number of data (frame) retransmissions exceeds a predetermined value, and detects that the link has been disconnected via the wired interface 116 and the cable 17. Notify the routing daemon 190.

  The address conversion table 114 belongs to the MAC layer, and the MAC address of the wireless LAN terminal 11 is set to the MAC address of the controller device 18 for each wireless device for the eight wireless devices 1 to 8 constituting the wireless communication network 10. Store in association.

  The LLC module 115 belongs to the data link layer and executes the LLC protocol to connect and release a link with an adjacent wireless device.

  The wired interface 116 outputs the wired frame WIRF received from the controller device 18 via the cable 17 to the LLC module 115 and transmits the wired frame WIRF received from the LLC module 115 to the controller device 18 via the cable 17.

  The input unit 181 of the operation device 18 receives a message and data destination input by the operator of the wireless device 1, and outputs the received message and destination to the e-mail application 183. The display unit 182 displays messages and the like according to control from the electronic mail application 183.

  The e-mail application 183 generates data based on the message from the input unit 181 and the destination and outputs the data to the communication control unit 184.

  The wired interface 185 transmits the wired frame WIRF from the IP module 186 to the wireless LAN terminal 11 via the cable 17, and transmits the wired frame WIRF received from the wireless LAN terminal 11 via the cable 17 to the IP module 186. .

  The IP module 186 belongs to the Internet layer and generates an IP packet. The IP packet includes an IP header and an IP data portion for storing a packet of a higher protocol. When IP module 186 receives data from TCP module 188, IP module 186 stores the received data in the IP data section and generates an IP packet.

  When generating the IP packet, the IP module 186 stores the generated IP packet in the frame body, stores the destination MAC address in the header, and generates a wired frame WIRF.

  Then, the IP module 186 searches the routing table 187 according to the FSRLOC protocol (protocol based on the FSR protocol, hereinafter the same), which is a table-driven routing protocol, and transmits a route for transmitting the generated wired frame WIRF. To decide. When determining the route, the IP module 186 transmits the generated wired frame WIRF to the wireless LAN terminal 11 via the wired interface 185 and the cable 17, and transmits the wired frame WIRF to the transmission destination along the determined route. .

  Further, when receiving the wired frame WIRF from the wired interface 185, the IP module 186 extracts data from the received wired frame WIRF and transmits the data to the TCP module 188 or the UDP module 189.

  The routing table 187 belongs to the Internet layer and stores route information in association with each destination address, as will be described later.

  The TCP module 188 belongs to the transport layer and generates a TCP packet. The TCP packet is composed of a TCP header and a TCP data part for storing data of an upper protocol. Then, the TCP module 188 transmits the generated TCP packet to the IP module 186.

  The UDP module 189 belongs to the transport layer, broadcasts a link state packet created by the routing daemon 190, receives a link state packet broadcast from another wireless device, and outputs it to the routing daemon 190.

  The routing daemon 190 belongs to the process / application layer, monitors the execution state of other communication control modules, and processes requests from other communication control modules.

  In addition, the routing daemon 190 periodically exchanges route information with other wireless devices existing relatively close according to the FSRLOC protocol.

Further, the routing daemon 190 detects the longitudes and latitudes λ _EX and φ _EX of the wireless devices 2, 4, 5 and 8 detected in the wireless device adjacent to the wireless device 1 and the speed v _{EX of the} wireless devices 2, 4, 5 and 8. Is received from the wireless LAN terminal 11, the longitude and latitude λ _EX , φ _EX and the velocity v _EX are extracted from the wired frame WIRF.

Then, the routing daemon 190 substitutes the extracted longitudes and latitudes λ _EX and φ _EX into λ and φ of the following equations to obtain the positions PS_EX of the wireless devices 2, 4, 5, and 8.

When the routing daemon 190 obtains the position PS_EX of the wireless devices 2, 4, 5, and 8, it stores the position PS_EX and the speed v _EX of the wireless devices 2, 4, 5, and 8.

  Further, when receiving the received signal strength RSSI_SEF detected by the wireless interface module 112 of the wireless device 1 from the wireless interface module 112 of the wireless LAN terminal 11, the routing daemon 190 stores the received received signal strength RSSI_SEF.

Furthermore, when the routing daemon 190 receives the longitude / latitude λ _SEF and φ _SEF of the wireless device 1 and the speed v _SEF of the wireless device 1 from the GPS driver unit 110, the routing latitude 190 receives the received latitude and longitude λ _SEF and φ _SEF from the equation (1). And the position PS_SEF of the wireless device 1 is obtained.

  Then, the routing daemon 190 determines the distance between the wireless device 1 and the wireless devices 2, 4, 5, 8 based on the obtained position PS_SEF of the wireless device 1 and the position PS_EX of the wireless devices 2, 4, 5, 8. r12, r14, r15, and r18 are calculated, and the link metrics between the wireless device 1 and the wireless devices 2, 4, 5, and 8 are calculated based on the calculated distances r12, r14, r15, and r18 by a method that will be described later. Ask for.

  Further, the routing daemon 190 indicates the existence direction of the wireless devices 2, 4, 5, 8 with respect to the wireless device 1 based on the obtained position PS_SEF of the wireless device 1 and the position PS_EX of the wireless devices 2, 4, 5, 8. The angles θ12, θ14, θ15, and θ18 are calculated, and the calculated angles θ12, θ14, θ15, and θ18 are stored.

  Since the position PS_SEF and the position PS_EX are represented by xy coordinates, the routing daemon 190 can easily calculate the distances r12, r14, r15, r18 and θ12, θ14, θ15, θ18.

  Then, the routing daemon 190 dynamically creates the routing table 187 in the Internet layer by a method described later based on the obtained link metric and the path information received from the adjacent wireless devices 2, 4, 5, and 8. .

  The SMTP module 191 belongs to the process / application layer, and secures a full-duplex communication channel and exchanges messages based on data received from the e-mail application 183.

  As described above, the cable 17 connects the wired interface 116 of the wireless LAN terminal 11 to the wired interface 185 of the operation device 18. As a result, the wireless LAN terminal 11 is connected to the operating device 18 by the cable 17, and the wireless LAN terminal 11 and the communication control unit 184 of the operating device 18 constitute an ARPA Internet hierarchical structure for performing communication control.

  Note that each of the wireless devices 2 to 8 illustrated in FIG. 1 has the same configuration as the configuration of the wireless device 1 illustrated in FIG. 3.

  FIG. 4 is a plan view of the array antenna 12 shown in FIG. 2 in the xy plane. The antenna elements 121 to 126 are arranged in a substantially circular shape around the antenna element 127. When the wavelength of the radio wave transmitted and received by the array antenna 12 is λ, the distance between the antenna elements 121 to 126 and the antenna element 127 is approximately λ / 4.

  Thus, the array antenna 12 has a structure in which the antenna elements 121 to 126 as parasitic elements are arranged in a substantially circular shape around the antenna element 127 as a feeding element.

When the antenna control module 111 controls the beam pattern emitted from the array antenna 12 by supplying the control voltage sets CLV0 to CLV12 to the varactor diodes 131 to 136, the reactance set x _m = x _{m1 to} x of the varactor diodes 131 to 136 is controlled. Control voltage sets CLV0 to CLV12 are supplied to varactor diodes 131 to 136 so that _m6 changes according to the reactance set shown in Table 1.

Each of the control voltage sets CLV0 to CLV12 includes six voltages V1 to V6 corresponding to the six varactor diodes 131 to 136. Antenna control module 111, for example, set to "hi" reactance _x m1 _{~x m6} varactor diodes 131-136 supplies a voltage V1~V6 consisting -20V to varactor diodes 131 to 136 each consist of 0V set by supplying a voltage V1~V6 to varactor diode 131 to 136 respectively reactance _x m1 _{~x m6} varactor diodes 131-136 in "lo".

When the reactances x _{m1 to} x _m6 of the varactor diodes 131 to 136 are all “hi” (m = 0), the array antenna 12 radiates a beam pattern BPM0 close to an omni pattern. Further, when the reactance x _m1 of the varactor diode 131 is “hi” and the reactances x _{m2 to} x _m6 of the varactor diodes 132 to 136 are “lo” (m = 1), the array antenna 12 has a direction of 0 degree. A beam pattern BPM1 having directivity is emitted. Note that the positive direction of the x-axis is the 0 degree direction.

Furthermore, when the reactances x _m1 and x _{m2 of} the varactor diodes 131 and 132 are “hi” and the reactances x _{m3 to} x _m6 of the varactor diodes 133 to 136 are “lo” (m = 2), the array antenna 12 is The beam pattern BPM2 having directivity in the direction of 30 degrees is emitted.

Further, when the reactance x _m2 of the varactor diode 132 is “hi” and the reactances x _m1 , x _{m3 to} x _{m6 of} the varactor diodes 131 and 133 to 136 are “lo” (m = 3), the array antenna 12 is The beam pattern BPM3 having directivity in the direction of 60 degrees is emitted.

In the same manner, of the varactor diodes 131 to 136, a varactor diode varactor diodes 132 and 133 to set the reactance _{x m} "hi", varactor diode 133, varactor diodes 133 and 134, varactor diode 134, varactor diode 134 , 135, varactor diode 135, varactor diodes 135, 136, varactor diode 136, and varactor diodes 136, 131, the array antenna 12 has a 90 degree direction, a 120 degree direction, and a 150 degree direction, respectively. Beam patterns BPM4 to BPM12 having directivity are emitted in a direction of 180 degrees, a direction of 210 degrees, a direction of 240 degrees, a direction of 270 degrees, a direction of 300 degrees, and a direction of 330 degrees.

  As described above, the array antenna 12 can selectively radiate the omni beam pattern (beam pattern BPM0) and the beam patterns having the directivity (beam patterns BPM1 to BPM12) according to the control from the antenna control module 111.

  FIG. 5 is a configuration diagram of the link state packet LSP. The link state packet LSP includes a packet length, a MAC address, position information IFP, and neighboring device information IFT1, IFT2,.

  The position information IFP includes an X coordinate, a Y coordinate, a measurement time, a speed, and a direction. The X coordinate is the x coordinate calculated by the equation (1), and the Y coordinate is the y coordinate calculated by the equation (1). That is, the X coordinate and the Y coordinate are the x coordinate and the y coordinate calculated using the formula (1) based on the longitudes and latitudes λ and φ measured by the D-GPS receiver 14, and the position of each wireless device is determined. Show. The measurement time is the time when the D-GPS receiver 14 measures the longitudes and latitudes λ and φ, and consists of YYYY / MM / DD / HH / MM / SS.

  The speed is a speed measured by the D-GPS receiver 14 and represents a moving speed of each of the wireless devices 1 to 8. The direction consists of an angle θ calculated by the routing daemon 190 of each wireless device 1-8.

  Neighboring device information IFT1 includes transmission destination address 1, transmission destination sequence number 1, number of neighboring wireless devices 1, neighboring wireless device addresses 1 to N, received signal strengths 1 to N, angles 1 to N, and link metrics. 1 to N.

  The transmission destination address 1 is an IP address of a transmission destination wireless device. The transmission destination sequence number 1 represents the order in which the route for the wireless device represented by the transmission destination address 1 is generated. The number of adjacent wireless devices is the number of wireless devices adjacent to the wireless device that transmitted the link state packet LSP.

  [Address 1 of adjacent wireless device, received signal strength 1, angle 1, and link metric 1], ..., [Address N of adjacent wireless device, received signal strength N, angle N, and link metric N] Each is a set, and is represented by the IP address of the wireless device adjacent to the wireless device that transmitted the link state packet LSP, the received signal strength at the wireless device that transmitted the link state packet LSP, and the IP address. The direction in which the received wireless device exists with respect to the wireless device that transmitted the link state packet LSP, and the degree of stability of the path between the wireless device represented by the IP address and the wireless device that transmitted the link state packet LSP Represents.

  That is, each of the adjacent wireless device addresses 1 to N represents an IP address of a wireless device adjacent to the wireless device that transmitted the link state packet LSP, and each of the link metrics 1 to N is represented by an IP address. This represents the degree of stability of the path between the wireless device and the wireless device that transmitted the link state packet LSP, and each of the angles 1 to N indicates the wireless device that the wireless device represented by the IP address transmitted the link state packet LSP. It represents the direction that exists.

  FIG. 6 is a diagram showing an example of the routing table 187 shown in FIG. The routing table 187 includes a transmission destination address, an address of the adjacent wireless device (NextHop address), and a metric M1. The destination address, the NextHop address, and the metric M1 are associated with each other.

  The transmission destination address represents the IP address and the MAC address of the transmission destination wireless device. The NextHop address represents the IP address and MAC address of the next hopping wireless device.

  The metric M1 stores a numerical value determined according to the distance between two adjacent wireless devices. The metric M1 stores a relatively large numerical value when the distance is relatively long, and stores a relatively small numerical value when the distance is relatively short. A method for converting the distance into the metric M1 will be described later.

  In the example of the routing table 187 illustrated in FIG. 6, the first route is a route in which the wireless device as the transmission source is the wireless device 1 and the wireless device as the transmission destination is the wireless device 3, and the frame transmitted by the wireless device 1 is transmitted. It is shown that the terminal that relays the first message is the wireless device 2. The metric is “5”.

  The second route is a route in which the wireless device that is the transmission source is the wireless device 1 and the wireless device that is the transmission destination is the wireless device 3, and the wireless device that first relays the frame transmitted by the wireless device 1 is wireless. This indicates that the device 4 is used. The metric is “8”.

  Further, the third route is a route in which the wireless device of the transmission source is the wireless device 1 and the wireless device of the transmission destination is the wireless device 3, and the wireless device that first relays the frame transmitted by the wireless device 1 is wireless. This indicates that the device 5 is used. The metric is “7”.

  Further, the fourth route is a route in which the wireless device of the transmission source is the wireless device 1 and the wireless device of the transmission destination is the wireless device 3, and the wireless device that relays the frame transmitted by the wireless device 1 first is wireless. The device 8 is shown. The metric is “12”.

  A method for converting the distance between two adjacent wireless devices into a metric will be described. Table 2 shows the relationship between distance and metric.

  When the distance r is 10 m or less, the metric M1 is “1”, when the distance r is 10 m <r ≦ 30 m, the metric M1 is “2”, and when the distance r is 30 m <r ≦ 50 m The metric M1 is “4”, and when the distance r is 50 m <r ≦ 100 m, the metric M1 is “8”, and when the distance r is longer than 100 m, the metric M1 is “16”.

  Accordingly, when the routing daemon 190 calculates the distance r between two adjacent wireless devices, the routing daemon 190 detects a metric M1 corresponding to the calculated distance r with reference to Table 2, and the detected metric M1 is detected as route information ( The routing table 187 is created by adding to the metric of the route through the wireless device that has transmitted the rinse state packet LSP).

  This will be specifically described. 7 and 8 are first and second diagrams for explaining a method of creating the routing table 187 shown in FIG. 6, respectively. In the wireless communication network 10, when the wireless devices 1 to 8 do not recognize wireless devices existing around themselves, the wireless devices 1 to 8 measure their positions by the D-GPS receiver 14. Then, the link state packet LSP including the measured self position is broadcast.

  In FIG. 7, in order to explain the operation in which the wireless device 1 recognizes the route to the wireless device 3, the operation in which the wireless device 3 broadcasts its own position will be described.

  In the wireless device 3, the D-GS receiver 14 measures the longitude / latitudes λ, φ and the velocity v 3 of the wireless device 3 and transmits the measured longitude / latitudes λ, φ and velocity v 3 to the routing daemon 190 of the operation device 18. To do. Then, the routing daemon 190 of the controller device 18 receives the longitudes and latitudes λ and φ and the velocity v3, and substitutes the received longitudes and latitudes λ and φ into the expression (1) to position the wireless device 3 [X3, Y3]. Ask for.

  Thereafter, the routing daemon 190 of the wireless device 3 generates and broadcasts a link state packet LSP1 (see FIG. 7A) including the position [X3, Y3] of the wireless device 3 and the speed v3.

  The routing daemon 190 of the wireless device 7 receives the link state packet LSP1 broadcast from the wireless device 3, detects the MAC address of the wireless device 3 included in the received link state packet LSP1, and the link state packet LSP1 is wireless. Recognize that it was transmitted from the device 3.

  Then, the routing daemon 190 of the wireless device 7 extracts the position [X3, Y3] of the wireless device 3 included in the link state packet LSP1, and the longitude / latitude λ, of the wireless device 7 measured by the D-GPS receiver 14 φ and speed v 7 are received from the wireless LAN terminal 11.

  Thereafter, the routing daemon 190 of the wireless device 7 determines the distance r37 between the wireless device 3 and the wireless device 7 based on the position [X3, Y3] of the wireless device 3 and the position [X7, Y7] of the wireless device 7. = 25m), and the calculated distance r37 is converted into a metric M1 = 2 with reference to Table 2. Also, the routing daemon 190 of the wireless device 7 is based on the position [X3, Y3] of the wireless device 3 and the position [X7, Y7] of the wireless device 7, and an angle θ37 indicating the direction in which the wireless device 3 is present with respect to the wireless device 7. Is calculated.

  Then, the routing daemon 190 of the wireless device 7 stores the position [X7, Y7], the measurement time, and the speed v7 of the wireless device 7 in the X coordinate, the Y coordinate, the measurement time, and the speed of the position information IFP1, respectively. 3 address, “10”, “1”, wireless device 3 address, RSSI1, θ37 and “2” are the transmission destination address, transmission destination sequence number of adjacent device information IFT1, the number of adjacent wireless devices, The link state packet LSP2 is generated by storing the address, received signal strength, angle and link metric of the wireless device (see FIG. 7B), and the generated link state packet LSP2 is broadcast.

  When the routing daemon 190 of the wireless device 6 receives the link state packet LSP1, the link state packet LSP3 (see FIG. 7C) is generated and broadcast in the same manner as the routing daemon 190 of the wireless device 7.

  The routing daemon 190 of the wireless device 4 receives the link state packet LSP2 broadcast from the wireless device 7, detects the MAC address of the wireless device 7 included in the received link state packet LSP2, and the link state packet LSP2 is wireless. Recognize that it was transmitted from the device 7.

  Then, the routing daemon 190 of the wireless device 4 extracts the position [X7, Y7] of the wireless device 7 included in the link state packet LSP2, and the longitude / latitude λ, of the wireless device 4 measured by the D-GPS receiver 14 φ and speed v4 are received from the wireless LAN terminal 11.

  Thereafter, the routing daemon 190 of the wireless device 4 determines the distance r47 between the wireless device 4 and the wireless device 7 based on the position [X4, Y4] of the wireless device 4 and the position [X7, Y7] of the wireless device 7. = 28m), and the calculated distance r47 is converted into a metric M1 = 2 with reference to Table 2. Further, the routing daemon 190 of the wireless device 4 has an angle θ74 indicating the direction in which the wireless device 7 is present with respect to the wireless device 4 based on the position [X4, Y4] of the wireless device 4 and the position [X7, Y7] of the wireless device 7. Is calculated.

  Then, the routing daemon 190 of the wireless device 4 stores the position [X4, Y4], the measurement time, and the speed v4 of the wireless device 4 in the X coordinate, the Y coordinate, the measurement time, and the speed of the position information IFP2, respectively. 7 address, “10”, “1”, wireless device 7 address, RSSI3, θ74, and “2” are the transmission destination address, transmission destination sequence number of adjacent device information IFT2, the number of adjacent wireless devices, The link state packet LSP4 is generated by storing the address, received signal strength, angle, and link metric of the wireless device (see (d) of FIG. 7), and the generated link state packet LSP4 is broadcasted in the short term.

  Further, when broadcasting the link state packet LSP, the routing daemon 190 of the wireless device 7 broadcasts the link state packet LSP5 at a rate of once every three times.

  The link state packet LSP4 is a link state packet including route information whose destination is the wireless device 7 adjacent to the wireless device 4. On the other hand, the link state packet LSP5 is a rinse state packet including route information of a route from the wireless device 4 to the wireless device 3 via the wireless device 7.

  Since the routing daemon 190 of the wireless device 4 receives the link state packet LSP2 from the wireless device 7, it can detect that the wireless device 7 is a wireless device adjacent to the wireless device 3. Further, the routing daemon 190 of the wireless device 4 obtains the metric M1 = 2 based on the distance r47 between the wireless device 4 and the wireless device 7, as described above. Therefore, the routing daemon 190 of the wireless device 4 can recognize the route composed of the wireless device 4 -the wireless device 7 -the wireless device 3 and the number of hops from the wireless device 4 to the wireless device 3 = 2. Then, the routing daemon 190 of the wireless device 4 has a metric 2 between the wireless device 7 and the wireless device 3 (metric = 2 included in the link state packet LSP2), and a metric 2 between the wireless device 4 and the wireless device 7. Is added to obtain the metric = 4 of the route composed of the wireless device 4 -the wireless device 7 -the wireless device 3, and the link state packet LSP 5 is created and broadcast.

  The routing daemon 190 of the wireless device 2 receives the link state packet LSP2 broadcast from the wireless device 7, creates link state packets LSP4 and LSP5 in the same manner as the routing daemon 190 of the wireless device 4, and creates the created link state. The packet LSP4 is broadcast in a short cycle, and the link state packet LSP5 is broadcast in a long cycle.

  In addition, the routing daemon 190 of the wireless device 5 receives the link state packet LSP3 broadcast from the wireless device 6, and the route to the wireless device 6 adjacent to the wireless device 5 is the same as the routing daemon 190 of the wireless device 4. A link state packet including the route information of the route to the wireless device 3 and a link state packet including the route information of the route to the wireless device 6 are broadcast in a short cycle. A link state packet including route information of a route to the wireless device 3 is broadcast at a long cycle. The same applies to the routing daemon 190 of the wireless device 8.

  The wireless device 1 receives the link state packet LSP6 shown in FIG. 8A from the wireless device 2 by broadcast, and receives the link state packet LSP5 shown in FIG. 8B from the wireless device 4 by broadcast. The link state packet LSP7 shown in (c) of FIG. 8 is received from the wireless device 5 by broadcast, and the link state packet LSP8 shown in (d) of FIG.

  In this case, the distance r12 between the wireless device 1 and the wireless device 2 is calculated as 15 m, the distance r14 between the wireless device 1 and the wireless device 4 is calculated as 33 m, and the distance r15 between the wireless device 1 and the wireless device 5 is calculated. Is calculated as 11 m, and the distance r18 between the wireless device 1 and the wireless device 8 is calculated as 40 m.

  The routing daemon 190 of the wireless device 1 extracts the MAC address of the wireless device 2 from the MAC address of the link state packet LSP6, and recognizes that the link state packet LSP6 has been received from the wireless device 2. Further, the routing daemon 190 of the wireless device 1 extracts the MAC address of the wireless device 4 from the MAC address of the link state packet LSP5, and recognizes that the link state packet LSP5 has been received from the wireless device 4.

  Similarly, the routing daemon 190 of the wireless device 1 recognizes that the link state packets LSP7 and LSP8 have been received from the wireless devices 5 and 8, respectively.

  Then, the routing daemon 190 of the wireless device 1 uses the link state packet based on the “address of the wireless device 3” (consisting of the IP address and MAC address of the wireless device 3) stored in the transmission destination address of the link state packet LSP6. The LSP 6 recognizes that it includes route information whose destination is the wireless device 3. Similarly, the routing daemon 190 of the wireless device 1 is based on “the address of the wireless device 3” (consisting of the IP address and the MAC address of the wireless device 3) stored in the transmission destination addresses of the link state packets LSP5, LSP7, and LSP8. Thus, it is recognized that the link state packets LSP5, LSP7, and LSP8 include route information that has the wireless device 3 as a transmission destination.

  Thereafter, the routing daemon 190 of the wireless device 1 extracts the X coordinate = X2 and the Y coordinate = Y2 stored in the position information IFP3 of the link state packet LSP6, and the extracted X coordinate = X2 and Y coordinate = Y2, Based on the position information of the wireless device 1 = [X1, Y1], a distance r12 = 15 m between the wireless device 1 and the wireless device 2 is calculated. Then, the routing daemon 190 of the wireless device 1 refers to Table 2 and obtains a metric = 2 corresponding to the distance r12 = 15 m between the wireless device 1 and the wireless device 2.

  Next, the routing daemon 190 of the wireless device 1 extracts metric = 3 stored in the link metric of the adjacent device information IFT3 of the link state packet LSP6, and the wireless device 1 and the wireless device 2 are extracted to the extracted metric = 3. The metric = 2 determined based on the distance r12 between the two is added to obtain the metric = 5. Then, the routing daemon 190 of the wireless device 1 stores the address of the wireless device 3 in the destination address, stores the address of the wireless device 2 in the NextHop address, stores “5” in the metric, and stores the address of the routing table 187. Route information on the first line is created (see (e) of FIG. 8).

  Further, the routing daemon 190 of the wireless device 1 extracts the X coordinate = X4 and Y coordinate = Y4 stored in the position information IFP4 of the link state packet LSP5, and the extracted X coordinate = X4 and Y coordinate = Y4, Based on the position information of the wireless device 1 = [X1, Y1], the distance r14 = 33m between the wireless device 1 and the wireless device 4 is calculated. Then, the routing daemon 190 of the wireless device 1 obtains metric = 4 corresponding to the distance r14 = 33 m between the wireless device 1 and the wireless device 4 with reference to Table 2.

  Next, the routing daemon 190 of the wireless device 1 extracts the metric = 4 stored in the link metric of the adjacent device information IFT4 of the link state packet LSP5, and the wireless device 1 and the wireless device 4 are added to the extracted metric = 4. The metric = 4 determined based on the distance r14 between is added to obtain the metric = 8. Then, the routing daemon 190 of the wireless device 1 stores the address of the wireless device 3 in the transmission destination address, stores the address of the wireless device 4 in the NextHop address, stores “8” in the metric, and stores the number in the routing table 187. Route information on the second line is created (see FIG. 8E).

  Further, the routing daemon 190 of the wireless device 1 extracts X coordinate = X5 and Y coordinate = Y5 stored in the position information IFP5 of the link state packet LSP7, and the extracted X coordinate = X5 and Y coordinate = Y5, Based on the position information of the wireless device 1 = [X1, Y1], a distance r15 = 11 m between the wireless device 1 and the wireless device 5 is calculated. Then, the routing daemon 190 of the wireless device 1 refers to Table 2 and obtains metric = 2 corresponding to the distance r14 = 11 m between the wireless device 1 and the wireless device 5.

  Next, the routing daemon 190 of the wireless device 1 extracts the metric = 5 stored in the link metric of the adjacent device information IFT5 of the link state packet LSP7, and the wireless device 1 and the wireless device 5 are extracted to the extracted metric = 5. The metric = 2 determined based on the distance r15 between the two is added to obtain the metric = 7. Then, the routing daemon 190 of the wireless device 1 stores the address of the wireless device 3 in the transmission destination address, stores the address of the wireless device 5 in the NextHop address, stores “7” in the metric, and stores the first in the routing table 187. Route information on the third line is created (see FIG. 8E).

  Further, the routing daemon 190 of the wireless device 1 extracts X coordinate = X8 and Y coordinate = Y8 stored in the position information IFP6 of the link state packet LSP8, and the extracted X coordinate = X8 and Y coordinate = Y8, Based on the position information of the wireless device 1 = [X1, Y1], a distance r18 = 40 m between the wireless device 1 and the wireless device 8 is calculated. Then, the routing daemon 190 of the wireless device 1 obtains a metric = 4 corresponding to the distance r18 = 40 m between the wireless device 1 and the wireless device 8 with reference to Table 2.

  Next, the routing daemon 190 of the wireless device 1 extracts the metric = 8 stored in the link metric of the adjacent device information IFT6 of the link state packet LSP8, and the wireless device 1 and the wireless device 8 are extracted to the extracted metric = 8. Metric = 4 determined based on the distance r18 between the two is added to obtain Metric = 12. Then, the routing daemon 190 of the wireless device 1 stores the address of the wireless device 3 in the transmission destination address, stores the address of the wireless device 8 in the NextHop address, stores “12” in the metric, and stores the address of the routing table 187. Route information on the fourth line is created (see (e) of FIG. 8).

  As a result, the routing daemon 190 of the wireless device 1 completes the routing table 187.

  As described above, in the present invention, the distance between two adjacent wireless devices is converted into a metric, and the converted metric is included in the route information as a route stability index indicating the degree of stability of the route, and the routing table 187 is created. . As shown in Table 2, when the distance is relatively short, the metric is relatively small, and when the distance is relatively long, the metric is relatively large. Therefore, a relatively small metric means that the route is more stable, and a relatively large metric means that the route is more unstable.

  When the distance is converted into a metric, the distance is converted into a plurality of regions (region RGE1 where the distance r is 10 m or less, region RGE2 where 10 m <r ≦ 30 m, region RGE3 where 30 m <r ≦ 50 m, region RGE4 where 50 m <r ≦ 1000 m, Further, as the distance r becomes longer in the direction from the region RGE1 to the region RGE5, the metric M1 increases in accordance with a power of 2. That is, as the distance r increases linearly, the metric M1 increases exponentially.

  Thus, by increasing the metric M1 as the path stability index exponentially as the distance r increases linearly (that is, the metric M1 as the path stability index increases as the distance r decreases linearly). By making it functionally small), a path with a greater degree of stability can be easily selected.

  That is, when the metric M1 is linearly increased as the distance r increases linearly, the difference in the metric M1 due to the difference in the distance r decreases. In the routing table 187, the metric in the entire route from the wireless device 1 to the wireless device 3 (= added value of the metrics of each route) is stored, so the value does not change greatly even if the distance r varies. When the metric is used, a large difference does not occur in a plurality of metrics assigned to a plurality of paths from the transmission source to the transmission destination.

  On the other hand, when the metric M1 is exponentially increased as the distance r increases linearly, the metric M1 changes greatly with respect to the change of the distance r. There will be a large difference between the given metrics.

  Therefore, in the present invention, the metric increases exponentially as the distance r increases linearly.

  The other wireless devices 2 to 8 shown in FIG. 1 also create the routing table 187 in the same manner as the wireless device 1 described above.

  FIG. 9 is a diagram showing an example of the address conversion table 114 shown in FIG. The address conversion table 114 includes the MAC address of the controller device 18 and the MAC address of the wireless LAN terminal 11. The address conversion table 114 stores the MAC addresses MAC1 to MAC8 of the operation devices 18 of the wireless devices 1 to 8 in association with the MAC addresses MAC11 to MAC81 of the wireless LAN terminal 11 of the wireless devices 1 to 8, respectively. That is, the address conversion table 114 stores the MAC address of the controller device 18 in association with the MAC address of the wireless LAN terminal 11 for each wireless device for the wireless devices 1 to 8.

  As described above, in each of the wireless devices 1 to 8, the wireless LAN terminal 11 transmits the MAC address of the operation device 18 and the wireless LAN terminal 11 to all the wireless devices 1 to 8 existing in the wireless communication network 10. The address conversion table 114 in which the MAC addresses are associated with each other is held.

  FIG. 10 is a configuration diagram of the wired frame WIRF. The wired frame WIRF includes an FCS (Frame Control Sequence) 11A, a frame body 12A, a data type (Data Type) 13A, a source address (SA) 14A, and a destination address (DA: Destination Address) 15A. It consists of.

  The FCS 11A has a length of 4 octets. The frame main body 12A has a length of 46 octets or more and stores data to be transmitted. The data type 13A, the transmission source address (SA) 14A, and the transmission destination address (DA) 15A constitute an Ethernet (registered trademark) header and has a total length of 14 octets. The data type 13A indicates the type of data stored in the frame body 12A.

  The transmission source address (SA) 14A stores the MAC address (any one of MAC1 to MAC8) of the operation device 18 of the transmission source wireless device. The transmission destination address (DA) 15A stores the MAC address (any one of MAC1 to MAC8) of the operation device 18 of the transmission destination wireless device.

FIG. 11 is a schematic diagram showing the configuration of the GPS data acquisition request signal D _GPS . The acquisition request signal D _GPS includes an operation / maintenance device message type, a data size, a message ID, and a transmission source task ID.

  The operation / maintenance device message type consists of 0xACDE4801. This 0xACDE 4801 is fixed. The data size is 0x08. The message ID is “24”, and the transmission source task ID is “11”.

FIG. 12 is a schematic diagram showing a configuration of a response signal R _{GPS to} the GPS data acquisition request signal D _GPS . The response signal R _GPS includes an operation / maintenance device message type, a data size, a message ID, a transmission source task ID, and GPT1 to GPT10.

  The operation / maintenance device message type consists of 0xACDE4801. This 0xACDE 4801 is fixed. The data size is 0x34C. The message ID is “25”. The source task ID is “6”.

  FIG. 13 is a diagram showing a format of GPT1 shown in FIG. GPT1 includes information validity / invalidity, a terminal MAC address, a terminal IP address, and GPS data. Information valid / invalid consists of “0” or “1”. “0” represents that GPT1 is invalid, and “1” represents that GPT1 is valid.

  The terminal MAC address has a data length of 6 bytes, and is composed of the MAC address of the wireless device whose longitude and latitudes λ and φ and the velocity v are measured. The terminal IP address has a data length of 4 bytes, and consists of the IP address of the wireless device whose longitude and latitudes λ and φ and the velocity v are measured. For example, when the IP address is “192.168.0.1”, “+ 06 = 0xC0, + 07 = 0xA8, + 08 = 0x00, + 09 = 0x01” is stored in the IP address.

  The GPS data has a data length of 52 bytes and includes the longitudes and latitudes λ and φ and the speed v of each of the wireless devices 1 to 8.

  Each of GPT2 to GPT10 shown in FIG. 12 has the same configuration as that of GPT1 shown in FIG.

  FIG. 14 is a diagram showing the configuration of the GPS data shown in FIG. GPS data is received at GPS, reception status, raw latitude (degrees), raw latitude (minutes), raw latitude (seconds), character indicating north / south latitude, longitude (degrees), longitude (minutes), longitude (seconds) , Characters indicating east longitude / west longitude, speed, true direction, and front and rear G sensors.

  The GPS acquisition time represents the time when the GPS data was acquired, and consists of YYYY / MM / DD / HH / MM / SS. The measurement time of the link state packet LSP shown in FIG. The reception status consists of “A” indicating that positioning is in progress.

  The raw latitude (degrees), raw latitude (minutes), and raw latitude (seconds) are each composed of a frequency component, a fractional component, and a seconds component of the measured latitude φ. The character indicating north latitude / south latitude consists of “N” representing north latitude or “S” representing south latitude.

  Longitude (degrees), longitude (minutes), and longitude (seconds) are each composed of a frequency component, a fraction component, and a seconds component of the measured longitude λ. The character indicating east longitude / west longitude is composed of “E” representing east longitude or “W” representing west longitude.

  The speed is composed of the respective speeds of the wireless devices 1 to 8, and a numerical value in the range of 0 to 999.9 knots is stored. The true direction is composed of the moving directions of the wireless devices 1 to 8, and a numerical value in the range of 0 to 359.9 degrees is stored. The speed and true direction constitute the speed v described above and are stored in the link state packet LSP. The front / rear G sensor has a detection value of +2.000 G in the range of 0.000 G to 4.0000 G.

  FIG. 15 is a configuration diagram of the radio frame RFF. The radio frame RFF includes an FCS 11B, a frame body 12B, a PAD 13B, an 802.2 SNAP 14B, an 802.2 LLC 15B, and an IEEE 802.11 MAC header 16B.

  FCS 11B has a length of 4 octets. The frame body 12B stores various data. The PAD 13B has a length of 2 octets and stores “0x0000”. The 802.2SNAP 14B has a length of 5 octets and stores “0x000000CAFE”. The 802.2LLC 15B has a length of 3 octets and stores “0xAAAA03”. The 802.2SNAP 14B and 802.2LLC 15B constitute a logical link control unit.

  The IEEE 802.11 MAC header 16B includes a MAC address (any of MAC11 to MAC81) of the wireless LAN terminal 11 of the transmission source wireless device and a MAC address (any of MAC11 to MAC81 of the wireless LAN terminal 11 of the transmission destination wireless device). ) Etc.

  Each of the wireless devices 1 to 8 illustrated in FIG. 1 includes the wireless LAN terminal 11 and the operation device 18 as described above. And when each radio | wireless apparatus 1-8 transmits data, the operation apparatus 18 is the MAC address (any of MAC1-MAC8) of the operation apparatus 18 which comprises the transmission destination radio | wireless apparatus (any one of the radio | wireless apparatuses 1-8). A wired frame WIRF including () is generated, and the generated wired frame WIRF is transmitted to the wireless LAN terminal 11 via the cable 17.

  Then, the wireless LAN terminal 11 converts the wired frame WIRF received from the operation device 18 into the wireless frame RFF, and the converted wireless frame RFF via the array antenna 12 configures the wireless device of the transmission destination. Send to.

  FIG. 16 is a conceptual diagram illustrating conversion between the wired frame WIRF and the radio frame RFF. FIG. 16 illustrates conversion between the wired frame WIRF and the wireless frame RFF when the wireless device 1 is a transmission source wireless device and the wireless device 2 is a transmission destination wireless device.

  The operating device 18 of the wireless device 1 stores its own MAC address MAC1 in the transmission source address (SA) 14A, stores the MAC address MAC2 of the operating device 18 of the wireless device 2 in the transmission destination address (DA) 15A, and data Is generated in the frame main body 12A, and the generated wired frame WIRF1 is transmitted to the wireless LAN terminal 11 via the cable 17.

  When receiving the wired frame WIRF1 via the cable 17, the wireless LAN terminal 11 of the wireless device 1 detects the MAC address MAC2 included in the wired frame WIRF1 as a transmission destination address. Then, the wireless LAN terminal 11 of the wireless device 1 refers to the address conversion table 114 and extracts the MAC address MAC21 corresponding to the MAC address MAC2. That is, the wireless LAN terminal 11 of the wireless device 1 uses the MAC address MAC21 of the wireless LAN terminal 11 provided corresponding to the operation device 18 of the wireless device 2 that is the transmission destination of the wired frame WIRF1 based on the MAC address MAC2. The address conversion table 114 is extracted for reference.

  Then, the wireless LAN terminal 11 of the wireless device 1 stores the [frame main body 12A / data type 13A / source address (SA) 14A / transmission destination address (DA) 15A] of the wired frame WIRF1 in the frame main body 12B. The MAC address MAC11 and the extracted MAC address MAC21 are stored in the IEEE802.11MAC header 16B, and a radio frame RFF1 with the FCS 11B added is generated.

  The wireless LAN terminal 11 of the wireless device 1 transmits the generated wireless frame RFF1 to the wireless LAN terminal 11 of the wireless device 2 via the array antenna 12. In this case, the antenna control module 111 of the wireless device 1 controls the array antenna 12 to radiate the omni beam pattern BPM0 by the method described above. That is, the wireless LAN terminal 11 of the wireless device 1 transmits the wireless frame RFF1 to the wireless LAN terminal 11 of the wireless device 2 using the omni beam pattern BPM0.

  The wireless LAN terminal 11 of the wireless device 2 sets the beam pattern of the array antenna 12 to the omni beam pattern BPM0, receives the wireless frame RFF1, and stores the frame [frame body 12A stored in the frame body 12B of the received wireless frame RFF1. / Data type 13A / source address (SA) 14A / destination address (DA) 15A] and the extracted [frame body 12A / data type 13A / source address (SA) 14A / destination address (DA ) 15A] is added with FCS 11A to reproduce the wired frame WIRF1 generated by the operating device 18 of the wireless device 1.

  Then, the wireless LAN terminal 11 of the wireless device 2 transmits the reproduced wired frame WIRF1 to the operation device 18 via the cable 17. Then, the operating device 18 of the wireless device 2 receives the wired frame WIRF1 generated by the operating device 18 of the wireless device 1.

  As described above, in the present invention, when transmitting data to the destination wireless device 2, in the source wireless device 1, the operating device 18 has the MAC address of the operating device 18 constituting the destination wireless device 2. A wired frame WIRF1 having MAC2 as the destination MAC address is generated and transmitted to the wireless LAN terminal 11 via the cable 17, and the wireless LAN terminal 11 is provided corresponding to the operation device 18 constituting the transmission destination wireless device 2. The extracted MAC address MAC21 of the wireless LAN terminal 11 is extracted with reference to the address conversion table 114, the extracted MAC address MAC21 is stored in the destination MAC address, and the wired frame WIRF1 generated by the operating device 18 is stored in the frame body 12B. To generate the wireless frame RFF1 and store the wired frame WI. Converting the F1 to the radio frame RFF1.

  Further, in the transmission destination wireless device 2, the wireless LAN terminal 11 sends [frame body 12A / data type 13A / source address (SA) 14A / destination address (DA) 15A] from the wireless frame RFF1 to the wired frame WIRF1. The wired frame WIRF1 is extracted and reproduced, and the controller device 18 receives the wired frame WIRF1 reproduced by the wireless LAN terminal 11.

  As described above, the operating device 18 of the wireless device 1 that is the transmission source generates the wired frame WIRF1 in which the MAC address MAC1 of the operating device 18 of the wireless device 2 that is the transmission destination is set as the destination MAC address to the wireless LAN terminal 11. If transmitted, the wireless LAN terminal 11 of the wireless device 1 that is the transmission source is wired to the wireless frame RFF1 that has the MAC address MAC21 of the wireless LAN terminal 11 corresponding to the operation device 18 of the wireless device 2 that is the transmission destination as the destination MAC address. The frame WIRF1 is converted and transmitted.

  In this case, in the transmission source wireless device 1, the operation device 18 does not generate a wired frame that is destined for the wireless LAN terminal 11 of the wireless device 1, but the operation device 18 of the transmission destination wireless device 2 is the destination. The wireless LAN terminal 11 generates a wired frame WIRF1 to be transmitted to the wireless LAN terminal 11, and the wireless LAN terminal 11 includes a wired frame WIRF1 and a wireless address including the MAC address MAC21 of the wireless LAN terminal 11 constituting the wireless device 2 as a transmission destination. Since the frame RFF1 is generated and transmitted, transmission of the wired frame WIRF1 from the operation device 18 to the wireless LAN terminal 11 in the wireless device 1 does not correspond to “1 hop”.

  Also in the wireless device 2 as the transmission destination, the wireless LAN terminal 11 does not generate a wired frame in which its own MAC address MAC21 is set as the MAC address of the transmission source, but uses the operating device 18 of the wireless device 1 as the transmission source. Therefore, the transmission of the wired frame WIRF1 from the wireless LAN terminal 11 to the operation device 18 in the wireless device 2 does not correspond to “1 hop”.

  Therefore, transmission of the wired frame WIRF1 from the operation device 18 of the wireless device 1 as the transmission source to the operation device 18 of the wireless device 2 as the transmission destination is performed by the wireless LAN terminal 11 of the wireless device 1 and the wireless LAN terminal of the wireless device 2. 11 is composed of “1 hop” by transmission of the radio frame RFF1.

  As a result, even when each of the wireless devices 1 to 8 is configured by the operation device 18 and the wireless LAN terminal 11, each of the wireless devices 1 to 8 suppresses an increase in the number of hops, that is, suppresses a decrease in throughput. Data can be sent to the destination.

  Further, as described above, in each of the wireless devices 1 to 8, the wireless LAN terminal 11 transmits the MAC address of the operation device 18 and the wireless communication to all the wireless devices 1 to 8 existing in the wireless communication network arc 10. An address conversion table 114 that associates the MAC address of the LAN terminal 11 is held.

  Accordingly, when the wireless LAN terminal 11 of each of the wireless devices 1 to 8 receives the wired frame WIRF1 from the operation device 18, the wireless LAN terminal 11 corresponding to the MAC address of the operation device 18 constituting the transmission destination wireless device included in the wired frame WIRF1. The MAC address of the LAN terminal 11 can be easily extracted. As a result, the wireless LAN terminals 11 of the wireless devices 1 to 8 can easily convert the wired frame WIRF1 into the wireless frame RFF1.

  As described above, the wired frame WIRF is converted into the wireless frame RFF and transmitted when the wired frame WIRF is destined for one wireless device, and the wired frame WIRF includes a broadcast address or a multicast address. In this case, the wireless LAN terminal 11 of the transmission source wireless device broadcasts or multicasts the wired frame WIRF received from the operation device 18 as it is.

  Therefore, when creating the routing table 187, the operating device 18 of each of the wireless devices 1 to 8 stores the link state packets LSP1 to LSP8 in the frame body 12A and stores the broadcast address in the transmission destination address (DA) 15A. The wired frame WIRF2 is created and transmitted to the wireless LAN terminal 11, and the wireless LAN terminal 11 detects that the broadcast address is stored in the transmission destination address (DA) 15A of the wired frame WIRF2 received from the operation device 18. Then, the wired frame WIRF2 is broadcast.

(Route determination method 1)
Each of the wireless devices 1 to 8 obtains a metric determined according to the distance between two adjacent wireless devices by the above-described method, and reflects the obtained metric on the route to the transmission destination, and stores the routing table 187. create. Then, each of the wireless devices 1 to 8 determines the route having the smallest metric to the transmission destination as the route to the transmission destination in the created routing table 187.

  As described above, when the distance r between two adjacent wireless devices is relatively short, the metric is set to a relatively small value, and when the distance r between two adjacent wireless devices is relatively long, Since the metric is set to a relatively large value, determining the route with the smallest metric to the destination as the route to the destination means that the route with the shortest distance to the destination is the route to the destination. It corresponds to determining as.

(Route determination method 2)
In the route determination method 1 described above, the route to the transmission destination is determined using the metric M1 determined according to the distance between two adjacent wireless devices. In this route determination method 2, a metric M1 determined according to the distance between two adjacent wireless devices and a metric M2 determined according to the received signal strength RSSI between the two adjacent wireless devices are used. To determine the route to the destination.

  FIG. 17 is a diagram illustrating an example of a routing table using the metric M2 determined according to the received signal strength RSSI. The routing table 187A is the same as the routing table 187 except that the metric M1 of the routing table 187 shown in FIG. The metric M2 is a value determined according to the received signal strength RSSI. A method for converting the received signal strength RSSI into the metric M2 will be described later.

  In the example of the routing table 187A shown in FIG. 17, the first route shown in FIG. 6 has a metric M2 of “8”, the second route has a metric M2 of “6”, and the third route The path has a metric M2 of “10”, and the fourth path has a metric M2 of “12”.

  A method for converting the received signal strength RSSI into a metric will be described. Table 3 shows the relationship between the received signal strength and the metric.

  When the received signal strength is higher than −55 dBm, the metric is “1”, and when the received signal strength is in a range from −65 dBm to −55 dBm, the metric is “2” and the received signal strength is from −75 dBm to When the range is up to −65 dBm, the metric is “4”, and when the received signal strength is in the range from −85 dBm to −75 dBm, the metric is “8”, and the received signal strength is weaker than −85 dBm. Then, the metric becomes “16”.

  When the metric M2 determined according to the received signal strength RSSI is used, when the radio interface module 112 receives a link state packet LSP from another radio device, the radio interface module 112 detects the received signal strength RSSI of the received link state packet LSP. The detected received signal strength RSSI is transmitted to the routing daemon 190.

  When receiving the received signal strength from the radio interface module 112, the routing daemon 190 detects a metric M2 corresponding to the received received signal strength with reference to Table 3, and transmits the detected metric M2 to the route information. The routing table 187A is created by adding to the metric of the route through the wireless device.

  This will be specifically described. FIG. 18 is a diagram for explaining a method of creating the routing table 187A shown in FIG. The wireless device 1 receives link state packets LSP9 to LSP12 from the wireless devices 2, 4, 5, and 8, respectively.

  In this case, in the wireless device 1, the wireless interface module 112 detects the received signal strength RSSI1 (= −65 dBm to −55 dBm) when the link state packet LSP9 is received from the wireless device 2, and the link state packet from the wireless device 4 The received signal strength RSSI2 (= −65 dBm to −55 dBm) when the LSP10 is received is detected, and the received signal strength RSSI3 (= −65 dBm to −55 dBm) when the link state packet LSP11 is received from the wireless device 5 is detected. The received signal strength RSSI4 (= −75 dBm to −65 dBm) when the link state packet LSP12 is received from the wireless device 8 is detected. Then, the wireless interface module 112 of the wireless device 1 transmits the detected received signal strengths RSSI1, RSSI2, RSSI3, RSSI4 to the routing daemon 190 of the controller device 18 via the wired interface 116 and the cable 17.

  Further, the routing daemon 190 of the controller device 18 receives the link state packets LSP9 to LSP12 from the wireless devices 2, 4, 5, and 8, respectively. The link state packet LSP9 is obtained by replacing the metric M1 = 3 of the link state packet LSP6 shown in (a) of FIG. 8 with the metric M1 = 3 and the metric M2 = 6. The metric M1 = 4 of the link state packet LSP5 shown in b) is replaced with the metric M1 = 4 and the metric M2 = 4, and the link state packet LSP11 is the metric of the link state packet LSP7 shown in (c) of FIG. M1 = 5 is replaced with metric M1 = 5 and metric M2 = 8, and the link state packet LSP12 sets the metric M1 = 8 and metric M1 = 8 of the link state packet LSP8 shown in FIG. Instead of M2 = 8 .

  Then, the routing daemon 190 of the wireless device 1 extracts the MAC address of the wireless device 2 from the MAC address of the link state packet LSP9, and recognizes that the link state packet LSP9 has been received from the wireless device 2. Further, the routing daemon 190 of the wireless device 1 extracts the MAC address of the wireless device 4 from the MAC address of the link state packet LSP10, and recognizes that the link state packet LSP10 has been received from the wireless device 4.

  Similarly, the routing daemon 190 of the wireless device 1 recognizes that the link state packets LSP11 and LSP12 have been received from the wireless devices 5 and 8, respectively.

  Then, the routing daemon 190 of the wireless device 1 determines the link state packet based on the “address of the wireless device 3” (consisting of the IP address and MAC address of the wireless device 3) stored in the transmission destination address of the link state packet LSP9. The LSP 9 recognizes that it includes route information whose destination is the wireless device 3. Similarly, the routing daemon 190 of the wireless device 1 is based on “the address of the wireless device 3” (consisting of the IP address and MAC address of the wireless device 3) stored in the transmission destination addresses of the link state packets LSP10, LSP11, and LSP12. Thus, it is recognized that the link state packets LSP10, LSP11, and LSP12 include route information that has the wireless device 3 as a transmission destination.

  Thereafter, the routing daemon 190 of the wireless device 1 extracts the metric M2 = 6 stored in the link state packet LSP9 and receives the link state packet LSP9 received from the wireless device 2 for the extracted metric M2 = 6. A metric M2 = 2 determined according to the signal strength is added to obtain a metric M2 = 8.

  Then, the routing daemon 190 of the wireless device 1 stores the address of the wireless device 3 in the transmission destination address, stores the address of the wireless device 2 in the NextHop address, stores “8” in the metric, and stores the address of the routing table 187A. Route information on the first line is created (see FIG. 18E).

  Also, the routing daemon 190 of the wireless device 1 extracts the metric M2 = 4 stored in the link state packet LSP10, and receives the link state packet LSP10 received from the wireless device 4 for the extracted metric M2 = 4. The metric M2 = 2 determined according to the signal strength is added to obtain the metric M2 = 6.

  Then, the routing daemon 190 of the wireless device 1 stores the address of the wireless device 3 in the transmission destination address, stores the address of the wireless device 4 in the NextHop address, stores “6” in the metric, and stores the address of the routing table 187A. Route information on the second line is created (see (e) of FIG. 18).

  Further, the routing daemon 190 of the wireless device 1 extracts the metric M2 = 8 stored in the link state packet LSP11, and receives the link state packet LSP11 received from the wireless device 5 for the extracted metric M2 = 8. A metric M2 = 2 determined according to the signal strength is added to obtain a metric M2 = 10.

  Then, the routing daemon 190 of the wireless device 1 stores the address of the wireless device 3 in the transmission destination address, stores the address of the wireless device 5 in the NextHop address, stores “10” in the metric, and stores the address of the routing table 187A. Route information on the third line is created (see (e) of FIG. 18).

  Furthermore, the routing daemon 190 of the wireless device 1 extracts the metric M2 = 8 stored in the link state packet LSP12, and receives the link state packet LSP12 from the wireless device 8 for the extracted metric M2 = 8. The metric M2 = 12 is obtained by adding the metric M2 = 4 determined according to the signal strength.

  The routing daemon 190 of the wireless device 1 stores the address of the wireless device 3 in the transmission destination address, stores the address of the wireless device 8 in the NextHop address, stores “12” in the metric, and stores the address of the routing table 187A. Route information on the fourth line is created (see (e) of FIG. 18).

  As a result, the routing daemon 190 of the wireless device 1 completes the routing table 187A.

  In the route determination method 2, the routing daemon 190 of the wireless device 1 also creates the above-described routing table 187 based on the metric M1 included in the link state packets LSP9 to LSP12. That is, in the route determination method 2, the routing daemon 190 of the wireless device 1 includes the routing table 187 using the metric M1 determined based on the distance between two adjacent wireless devices as a route index, and the two adjacent wireless devices. A routing table 187A is created that uses the metric M2 determined based on the received signal strength between them as a path index.

  Then, when wireless communication is performed by determining a route to the transmission destination based on the routing table 187, if the quality of the wireless communication becomes lower than the threshold value, the route to the transmission destination based on the routing table 187A. When the wireless communication quality is lower than the threshold when the route to the transmission destination is determined based on the routing table 187A and the wireless communication is performed, the routing table 187 Based on this, a route to the transmission destination is determined and wireless communication is performed.

  FIG. 19 is a timing chart of the packet transfer rate and the number of hops. FIG. 20 is another timing chart of the packet transfer rate and the number of hops. 19 and 20, the vertical axis represents the packet transfer rate and the number of hops, and the horizontal axis represents time. In FIG. 19, a curve k1 shows a packet transfer rate timing chart, and a curve k2 shows a hop count timing chart. Further, in FIG. 20, a curve k3 indicates a packet transfer rate timing chart, and a curve k4 indicates a hop count timing chart.

  19 shows the packet transfer rate and the number of hops when the route to the transmission destination is determined using the metric M2 determined according to the received signal strength (FSRMS protocol), and FIG. 20 shows the distance according to the distance. Represents the packet transfer rate and the number of hops when the route to the transmission destination is determined using the metric M1 determined in the above (FSRLOC protocol).

  When a route is determined using the FSRMS protocol, there is a region where the packet transfer rate changes greatly with the passage of time. In this region, the number of hops also changes and the route is frequently switched (FIG. 19). Curve k1, k2).

  On the other hand, when the route is determined using the FSRLOC protocol, the packet transfer rate and the number of hops are generally stable (see curves k3 and k4 in FIG. 20). Even in a region where the packet transfer rate and the number of hops change greatly when the FSRMS protocol is used, the packet transfer rate and the number of hops when the FSRLOC protocol is used are stable.

  In addition, when the FSRLOC protocol is used, there is a region where the packet transfer rate is greatly reduced due to the influence of multipath. In this region, when the FSRMS protocol is used, the packet transfer rate is stable.

  As described above, when the FSRMS protocol is used, there are an area where the path selection is stable and an unstable area. In the unstable area, the path selection can be performed stably by using the FSRLOC protocol. It is. In addition, when the FSRLOC protocol is used, there are an area where the path selection is stable and an unstable area. In the unstable area, the path selection can be performed stably by using the FSRMS protocol. .

  Therefore, in this route determination method 2, when the wireless communication is performed by determining the route to the transmission destination based on the metric M1 determined according to the distance, the quality of the wireless communication is lower than the threshold value. When it becomes lower, a route to the transmission destination is determined based on the metric M2 determined according to the received signal strength and wireless communication is performed, and a route to the transmission destination is determined based on the metric M2 determined according to the received signal strength. When the wireless communication quality is lower than the threshold value during wireless communication, the route to the transmission destination is determined based on the metric M1 determined according to the distance and the wireless communication is performed. Do.

  More specifically, the IP module 186 of the wireless device 1 selects a route based on the wireless device 2 having the smallest metric M1 to the transmission destination (= wireless device 3) based on the routing table 187, and Packets are transmitted and received with the wireless device 3 along the selected route. When the IP module 186 of the wireless device 1 transmits / receives a packet to / from the wireless device 3 along the route determined based on the routing table 187, the packet transfer rate (= packet arrival rate) exceeds the threshold value. Is lower, a route using the wireless device 4 having the smallest metric M2 to the transmission destination (= wireless device 3) as a relay is selected based on the routing table 187A, and the wireless device 3 and the wireless device 3 are selected along the selected route. Send and receive packets.

  Further, the IP module 186 of the wireless device 1 selects a route using the wireless device 4 having the smallest metric M2 to the transmission destination (= wireless device 3) as a relay based on the routing table 187A, and the selected route A packet is transmitted / received to / from the wireless device 3 along the line. When the IP module 186 of the wireless device 1 transmits / receives a packet to / from the wireless device 3 along the route determined based on the routing table 187A, the packet transfer rate (= packet arrival rate) exceeds the threshold value. Is lower, a route using the wireless device 2 having the smallest metric M1 to the transmission destination (= wireless device 3) as a relay is selected based on the routing table 187, and the wireless device 3 and the wireless device 3 are selected along the selected route. Send and receive packets.

  FIG. 21 is a diagram illustrating a relationship between received signal strength and distance in a multipath environment. In FIG. 21, the vertical axis represents received signal strength, and the horizontal axis represents distance. A curve k5 shows the relationship between received power and distance in vertical polarization, and a curve k6 shows the relationship between received power and distance in horizontal polarization.

  The received signal strength decreases exponentially as the distance increases, and when the distance exceeds about 2 m, a distance where the received signal strength greatly decreases appears periodically. The large decrease in the received signal strength is greater in the vertical polarization than in the horizontal polarization.

Therefore, in the present invention, a threshold value Prth is provided for the received signal strength RSSI, and the distance r between two adjacent wireless devices is a distance at which the received signal strength RSSI between adjacent wireless devices is lower than the threshold value Prth. When approaching r _ds , each of the wireless devices 1 to 8 determines, based on the routing table 187, a route that minimizes the metric M1 determined according to the distance as a route to the transmission destination.

In this case, the routing daemon 190 of each of the wireless devices 1 to 8 holds the relationship between the received signal strength and the distance shown in FIG. 21 as a map, and when a link state packet LSP is received from an adjacent wireless device, the link The X coordinate and the Y coordinate included in the state packet LSP are extracted, the distance r between the adjacent wireless devices is calculated by the above-described method, and when the calculated distance r approaches the distance r _ds , routing is performed. The IP module 186 is controlled so as to determine the route to the transmission destination based on the table 187.

  Then, the IP modules 186 of the wireless devices 1 to 8 determine a route to the transmission destination based on the routing table 187 in accordance with control from the routing daemon 190.

  As a result, a stable route to the transmission destination is selected using the metric M1 determined according to the distance before the route selected using the metric M2 determined according to the received signal strength RSSI becomes unstable. it can.

(Route selection method 3)
In this route selection method 3, the route to the transmission destination is determined based on the total metric _MTotal that is the sum of the metric M1 determined according to the distance and the metric M2 determined according to the received signal strength RSSI. . In this case, the total metric M _Total is calculated by the following equation.

M _Total = α × M1 + β × M2 (1)
In the formula (1), α is, for example, “1”, and β is, for example, “1/10”.

  FIG. 22 is another example of the routing table. In the route selection method 3, when the routing daemon 190 of each wireless device 1-8 receives the link state packet LSP from another wireless device, it extracts the X coordinate and Y coordinate included in the received link state packet LSP. The distance r between the wireless device on which it is mounted and the wireless device that transmitted the link state packet LSP is calculated using the extracted X and Y coordinates, and the calculated distance r is referred to Table 2. To metric M1.

  Further, the routing daemon 190 of each of the wireless devices 1 to 8 receives the received signal strength RSSI when the link state packet LSP is received from the wireless interface module 112 and refers to the received received signal strength RSSI with reference to Table 3. Convert to metric M2.

Then, the routing daemon 190 of each wireless device 1-8, the metric M1, M2 obtained by substituting the equation (1) calculates the total metric M _Total, to create a routing table 187B (see FIG. 22).

Then, the IP module 186 of each of the wireless devices 1 to 8 refers to the routing table 187B, determines the route with the minimum total metric M _Total as the route to the destination, and sends the destination along the determined route. Send and receive packets to and from.

  In the above, the wireless device 1 receives the link state packet LSP from the four wireless devices 2, 4, 5, and 8 adjacent to the wireless device 1, and communicates with itself and the four wireless devices 2, 4, 5, and 8. The four distances r12, r14, r15, and r18 are calculated. However, in the present invention, the present invention is not limited to this. In general, the wireless device 1 is generally adjacent to itself (n is a positive number). It receives link state packets LSP from (integer) wireless devices and calculates n distances between itself and n wireless devices.

  The wireless device 1 includes a metric M1 determined based on a distance r between two adjacent wireless devices in a plurality of wireless devices including the wireless devices 2, 3, 4, 5, 6, 7, and 8. The state packets LSP5 to LSP8 are received from any of the wireless devices 2, 4, 5, and 8 adjacent thereto. The wireless devices 3, 6, and 7 are wireless devices that exist at a position of 2 hops or more from the wireless device 1.

  Accordingly, the wireless device 1 has wireless devices 2, 4, 5, 8 adjacent to itself and wireless devices 3, 6, 6 that perform wireless communication with itself using any one of the wireless devices 2, 4, 5, 8 as a relay. 7 is received from one of the wireless devices 2, 4, 5, and 8 according to the distance r between two adjacent wireless devices. The wireless device 1 generally includes a plurality of wireless devices adjacent to itself and m wireless devices that perform wireless communication with itself using any one of the wireless devices as a repeater. The metric M1 determined according to the distance r between two adjacent wireless devices is received from any of the n wireless devices.

  In this case, the number of distances between two adjacent wireless devices in a plurality of wireless devices composed of n wireless devices and m wireless devices is generally k (k is a positive integer). is there.

  Then, the radio apparatus 1 has n metrics M1 (= n path stability indices) converted from n distances and k metrics M1 (= k path stability indices) converted from k distances. ) Is determined as a preferable route to the transmission destination, and wireless communication is performed with the transmission destination along the determined preferable route.

  In the above description, each of the wireless devices 1 to 8 has been described as transmitting and receiving the link state packet LSP including the metric M1 determined according to the distance r. However, in the present invention, the wireless device 1 is not limited thereto. ~ 8 transmits / receives the link state packet LSP including the calculated distance r, calculates the sum of the distances from the transmission source to the transmission destination based on the distance r included in the transmitted / received link state packet LSP, and calculates A route that minimizes the sum of distances may be determined as a route to the transmission destination.

  Further, each of the wireless devices 1 to 8 transmits / receives a link state packet LSP including its own position, and determines the distance from the transmission source to the transmission destination based on the position of each wireless device included in the transmitted / received link state packet LSP. A sum may be calculated, and a route that minimizes the sum of the calculated distances may be determined as a route to the transmission destination.

[Embodiment 2]
FIG. 23 is a diagram illustrating a configuration of the radio apparatuses 1 to 8 illustrated in FIG. 1 according to the second embodiment. In the second embodiment, each of radio apparatuses 1 to 8 shown in FIG. 1 includes radio apparatus 1A shown in FIG.

  The wireless device 1A is the same as the wireless device 1 except that the operating device 18 of the wireless device 1 shown in FIG. The operation device 18A is the same as the operation device 18 except that the communication control unit 184 of the operation device 18 shown in FIG.

  The communication control unit 184A is the same as the communication control unit 184 except that the routing table 187 of the communication control unit 184 shown in FIG. 3 is deleted and the IP module 186 is replaced with the IP module 186A.

  As described above, the wireless device 1A does not include the routing table 187, establishes a communication path with the transmission destination according to the on-demand type routing protocol, and communicates with the transmission destination along the established path. Perform wireless communication.

  Therefore, in the second embodiment, the routing daemon 190 does not have a function for creating the routing table 187.

  The IP module 186A generates and broadcasts a route request packet RREQ and establishes a route response packet RREP, which is a response to the route request packet RREQ, when establishing a route for wireless communication with the destination. Receive from. Thereby, a path for performing wireless communication between the transmission source and the transmission destination is established.

  The IP module 186A has the same functions as the IP module 186.

  In the second embodiment, the AODV protocol is basically used as an on-demand type routing protocol. In the following, selection of a route from a transmission source to a transmission destination when an on-demand type routing protocol is used will be described.

  In the AODV protocol, the wireless devices 1 to 8 transmit / receive route information using Hello packets. FIG. 24 is a configuration diagram of a Hello packet.

  The Hello packet HLP includes a type, a prefix, a metric, a hop count, a destination IP address, a destination sequence number, an original IP address, a lifetime, position information IFP, route information IFR1, IFR2,. Including.

  The type is HELLO indicating that it is a Hello packet HLP. The metric indicates the type of metric included in the path information IFR1 and IFR2. More specifically, the metric M1 is determined according to the distance r between two adjacent wireless devices, or the metric M2 is determined according to the received signal strength RSSI between the two adjacent wireless devices. Indicate. Therefore, M1 or M2 is stored in the metric.

  The hop count is 0 and indicates that the Hello packet HLP is not transferred. The transmission destination IP address consists of the IP address of the wireless device that has transmitted the Hello packet HLP. The transmission destination sequence number includes a sequence number of a route in the wireless device that has transmitted the Hello packet HLP.

  The original IP address consists of the IP address of the wireless device that has transmitted the Hello packet HLP. The lime time is a product of the number of times the transmission of the Hello packet HLP has failed (= ALLOWED_HELLO_LOSS) and the transmission interval of the Hello packet (= HELLO_INTERVAL).

  The position information IFP has the same configuration as the position information IFP of the link state packet LSP in the first embodiment.

  The path information IFR1 includes a transmission destination IP address 1, a transmission destination sequence number 1, Next1, a hop count 1, a metric 1, a flag 1, and a reservation.

  The destination IP address 1 is the IP address of the destination wireless device. The transmission destination sequence number 1 represents the order in which a route for the wireless device represented by the transmission destination IP address 1 is generated. Next 1 includes the IP address of the wireless device to which the wireless device that has transmitted the Hello packet HLP should transmit the packet when the wireless device that has transmitted the Hello packet HLP transmits the packet to the wireless device having the transmission destination IP address 1.

  The hop count 1 is composed of the total number of hops from the wireless device that has transmitted the Hello packet HLP to the wireless device having the transmission destination IP address 1. The metric 1 is a total metric from the wireless device that has transmitted the Hello packet HLP to the wireless device having the transmission destination IP address 1.

  The route information IFR2,... Has the same configuration as the route information IFR1.

  FIG. 25 is a diagram for explaining a method of establishing a route to a transmission destination in the second embodiment. When the route to the transmission destination is determined according to the AODV protocol, each of the wireless devices 1 to 8 of the wireless communication network 10 periodically broadcasts the Hello packet HLP and periodically sends the Hello packet HLP from other wireless devices. Receive.

  Then, when receiving the Hello packet HLP from the other wireless devices, the routing daemon 190 of each wireless device 1-8 extracts the X coordinate and the Y coordinate included in the received Hello packet HLP, and the extracted X coordinate and The distance r between the two wireless devices is calculated using the Y coordinate and the position information (consisting of the X coordinate and the Y coordinate) of the wireless device on which the device is mounted. Refer to Table 2 for the calculated distance r. To metric M1.

  For example, when receiving the Hello packet HLP from the wireless device 1, the routing daemon 190 of the wireless device 4 calculates the distance r24 between the wireless device 2 and the wireless device 4, and refers to the calculated distance r24 in Table 2. To metric = 2.

  As described above, the routing daemon 190 of each of the wireless devices 1 to 8 converts the distance between the adjacent wireless devices into the metric M1. And between each adjacent radio | wireless apparatuses of the radio | wireless apparatuses 1-8, the metric M1 shown in FIG. 25 shall be determined according to the distance r between two adjacent radio | wireless apparatuses.

  In such a situation, the IP module 186A of the wireless device 1 that is the transmission source generates a route request packet RREQ and broadcasts the generated route request packet RREQ.

  In each of the wireless devices 2, 4, 5, and 8, the IP module 186A receives the route request packet RREQ broadcast from the wireless device 1, and broadcasts the received route request packet RREQ. In this case, the route request packet RREQ includes [rreq / source / metric / destination]. “Rreq” represents that the packet RREQ is a route request packet indicating that the establishment of a route from the transmission source to the transmission destination is requested. The transmission source is composed of the IP address of the wireless device that transmits or relays the route request packet RREQ, and is updated each time the route request packet RREQ is relayed. Further, the metric is initially set to “0” and is updated every time the route request packet RREQ is relayed. Further, the transmission destination is made up of the IP address of the transmission destination wireless device with which the transmission source wireless device wishes to perform wireless communication, and is not changed.

  When receiving the route request packet RREQ from the wireless device 1, the IP module 186A of the wireless device 2 stores the metric = 2 between the wireless device 1 and the wireless device 2 in the metric of the received route request packet RREQ. Then, it stores its own IP address in the transmission source and broadcasts a route request packet RREQ consisting of [rreq / IP address of wireless device 2/2 / IP address of wireless device 3].

  In each of the wireless devices 4, 5, and 8, the IP module 186 </ b> A has a metric between the wireless device 1 and the wireless devices 4, 5, 8, as in the IP module 186 </ b> A of the wireless device 2. Are generated and broadcast.

  Upon receiving the route request packet RREQ = [rreq / IP address of wireless device 4/2 / IP address of wireless device 3] broadcast from wireless device 4, IP module 186A of wireless device 7 receives the received route request packet. RREQ = [rreq / IP address of wireless device 4/2 / IP address of wireless device 3] Metric = 2 is updated to Metric = 4 (= 2 + 2), and the IP address of wireless device 4 is the IP address of wireless device 7 The updated route request packet = [rreq / IP address of wireless device 7/4 / IP address of wireless device 3] is generated and broadcast.

  Further, the IP module 186A of the wireless device 7 also updates and broadcasts the metric and the transmission source for the route request packet RREQ received from the wireless device 2.

  Further, the IP module 186A of the wireless device 2 updates and broadcasts the metric and the transmission source of the route request packet RREQ received from the wireless device 4, and the IP module 186A of the wireless device 4 transmits the route request received from the wireless device 2. The metric and transmission source of the packet RREQ are updated and broadcast, and the IP module 186A of the wireless device 5 updates and broadcasts the metric and transmission source of the route request packet RREQ received from the wireless devices 2 and 8, and the wireless device 8 The IP module 186A updates the metric and source of the route request packet RREQ received from the wireless device 5 and broadcasts it, and the IP module 186A of the wireless device 6 transmits the route request packet RREQ received from the wireless devices 5 and 7 Metrics and Update the source broadcasts.

  As a result, the IP module 186A of the wireless device 3 that is the transmission destination receives a plurality of route request packets RREQ transmitted to the wireless device 3 via various routes. For example, the route request packet RREQ is transmitted to the wireless device 3 via a route including the wireless device 1 -the wireless device 2 -the wireless device 7 -the wireless device 6 -the wireless device 3, and the wireless device 1 -the wireless device 4 -the wireless device is transmitted. It is transmitted to the wireless device 3 via a route composed of the device 7 -the wireless device 3, and is transmitted via a route composed of the wireless device 1 -the wireless device 5 -the wireless device 2 -the wireless device 7 -the wireless device 6 -the wireless device 3. It is transmitted to the wireless device 3, and is transmitted to the wireless device 3 via a route including the wireless device 1 -the wireless device 8 -the wireless device 3.

  When receiving the plurality of route request packets RREQ, the IP module 186A of the wireless device 3 transmits the route request packet RREQ to the wireless device 3 in the metric included in each of the received plurality of route request packets. Update the metric by adding the metric between. Thereafter, the IP module 186A of the wireless device 3 determines a route having the smallest metric among the plurality of route request packets RREQ having the updated metric as a route for performing wireless communication with the transmission source.

  In this case, the IP module 186A of the wireless device 3 determines, for example, a route including the wireless device 1-wireless device 4-wireless device 7-wireless device 3 as a route for performing wireless communication with the transmission source.

  When determining the route, the IP module 186A of the wireless device 3 generates a route response packet RREP that is a response to the route request packet RREQ, and transmits the route response packet RREP to the transmission source wireless device 1.

  The route response packet RREP is composed of [rrep / destination 1 / source 1 / metric / hop count / source 2]. rrep represents that the packet RREP is a route response packet. The destination 1 is the IP address of the destination of the route response packet RREP, and is updated every time the route response packet RREP is relayed. The transmission source 1 is the IP address of the wireless device that transmits or relays the route response packet RREP, and is updated each time the route response packet RREP is relayed. The metric is initially set to “0” and is updated every time the route response packet RREP is relayed. The number of hops represents the number of communications between the transmission destination wireless device and the transmission source wireless device, and is updated each time the route response packet RREP is relayed. The transmission source 2 includes the IP address of the wireless device 1 that has transmitted the route request packet RREQ.

  Accordingly, the IP module 186A of the wireless device 3 generates the route response packet RREP = [rrep / IP address of the wireless device 7 / IP address of the wireless device 3/0/0 / IP address of the wireless device 1] to generate the wireless device. 7 to send.

  The IP module 186A of the wireless device 7 receives the route response packet RREP = [rrep / IP address of the wireless device 7 / IP address of the wireless device 3/0/0 / IP address of the wireless device 1] from the wireless device 3, The received route response packet RREP = [rrep / the IP address of the wireless device 7 / the IP address of the wireless device 3/0/0 / the IP address of the wireless device 1] is the route response packet RREP = [rrep / the IP of the wireless device 4]. Address / IP address of wireless device 7/4/1 / IP address of wireless device 1] and update to wireless device 4.

  The IP module 186A of the wireless device 4 receives the route response packet RREP = [rrep / IP address of the wireless device 4 / IP address of the wireless device 7/4/1 / IP address of the wireless device 1] and receives the received route. Response packet RREP = [rrep / IP address of wireless device 4 / IP address of wireless device 7/4/1 / IP address of wireless device 1] Route response packet RREP = [rrep / IP address of wireless device 1 / wireless device 4 IP address / 6/2 / IP address of the wireless device 1] and transmit to the wireless device 1.

  In the source wireless device 1, the IP module 186A receives the route response packet RREP = [rrep / IP address of the wireless device 1 / IP address of the wireless device 4/6/2 / IP address of the wireless device 1] The metric 8 is obtained by adding the metric = 2 to the metric = 6 of the received route response packet RREP = [rrep / IP address of the wireless device 1 / IP address of the wireless device 4/6/2 / IP address of the wireless device 1]. Ask for.

  Thus, the IP module 186A of the wireless device 1 recognizes that a route for performing wireless communication between the wireless device 1 and the wireless device 3 is established, and the total metric of the established route is Detect that it is “8”.

  In the establishment of the route between the transmission source and the transmission destination described above, the route request packet RREQ is transmitted to the transmission destination (= wireless device 3) via various routes. The route with the smallest added metric from the transmission source to the transmission destination is determined as the route between the transmission source and the transmission destination, and the metric added every time the route request packet RREQ is relayed is 2 adjacent. It is a metric determined according to the distance between two wireless devices.

  Therefore, determining the path between the transmission source and the transmission destination by the above-described method is to determine the path between the transmission source and the transmission destination based on the metric M1 determined according to the distance. Equivalent to.

  The wireless devices 4 and 7 that relay the route response packet RREP and the wireless device 1 that finally receives the route response packet RREP have a total metric between itself and the destination wireless device 3, that is, the self-to-destination radio. Since the number of hops to the device 3 and the adjacent wireless device when transmitting the packet to the transmission destination are recognized, these are stored in the path information IFR, and a Hello packet HLP is generated and broadcast periodically.

(Other route determination methods)
FIG. 26 is a further timing chart of the packet transfer rate and the number of hops. FIG. 27 is still another timing chart of the packet transfer rate and the number of hops. 26 and 27, the vertical axis represents the packet transfer rate and the number of hops, and the horizontal axis represents time. In FIG. 26, a curve k7 shows a packet transfer rate timing chart, and a curve k8 shows a hop count timing chart. Further, in FIG. 27, a curve k9 shows a packet transfer rate timing chart, and a curve k10 shows a hop count timing chart.

  26 shows the packet transfer rate and the number of hops when the route to the transmission destination is determined using the metric M2 determined according to the received signal strength (AODVLHA protocol), and FIG. 27 shows the distance according to the distance. Represents the packet transfer rate and the number of hops when the route to the transmission destination is determined using the metric M1 determined in this way (APDVLOC protocol).

  When a route is determined using the AODVLHA protocol, there is a region where the packet transfer rate has changed greatly with the passage of time. In this region, the number of hops also changes, and the route is frequently switched (FIG. 26). Curve k7, k8).

  On the other hand, when the route is determined using the APDVLOC protocol, the packet transfer rate and the number of hops are generally stable (see curves k9 and k10 in FIG. 27). Even in a region where the packet transfer rate and the number of hops change greatly when the AODVLHA protocol is used, the packet transfer rate and the number of hops when the AODVLOC protocol is used are stable.

  In addition, when the AODVLOC protocol is used, there is an area where the packet transfer rate is greatly reduced due to the influence of multipath. In this area, when the AODVLHA protocol is used, the packet transfer rate is stable.

  As described above, when the AODVLHA protocol is used, there are an area where the path selection is stable and an unstable area. In the unstable area, the path selection can be performed stably by using the AODVLOC protocol. It is. In addition, when the AODVLOC protocol is used, there are an area where the path selection is stable and an unstable area. In the unstable area, it is possible to select the path stably by using the AODVLHA protocol. .

  Therefore, in this other route determination method, when wireless communication is performed by determining a route between the transmission source and the transmission destination based on the metric M1 determined according to the distance, the quality of the wireless communication is determined. Is lower than the threshold, wireless communication is performed by determining a path between the transmission source and the transmission destination based on the metric M2 determined according to the reception signal strength, and is determined according to the reception signal strength. When wireless communication is performed by determining a route between a transmission source and a transmission destination based on the metric M2, and the wireless communication quality is lower than a threshold value, the metric determined according to the distance Wireless communication is performed by determining a route between the transmission source and the transmission destination based on M1.

  In this case, the route request packet RREQ consists of [rreq / source / metric M1 / metric M2 / destination], and each of the wireless devices 2, 4 to 8 that relay the route request packet RREQ receives the route request packet RREQ. Then, the received signal strength when the route request packet RREQ is received is detected, the detected received signal strength is converted into a metric M2 with reference to Table 3, and the metric M2 of the route request packet RREQ is updated.

  In the destination wireless device 3, the IP module 186A receives a plurality of route request packets REEQ from various routes. In this case, since the plurality of route request packets RREQ include the added metric M1 and the added metric M2, the IP module 186A of the wireless device 3 determines the metric in each of the received plurality of route request packets RREQ. Update each of M1 and metric M2. Then, the IP module 186A of the wireless device 3 transmits the updated metric M1 or the route with the smallest updated metric M2 to the transmission source in the plurality of route request packets RREQ including the updated metric M1 and metric M2. It is determined as a route to the destination.

  More specifically, a path between the transmission source and the transmission destination is determined based on the metric M1, wireless communication is performed between the transmission source and the transmission destination, and the communication quality is a threshold value. When the IP module 186A of the wireless device 3 newly receives a plurality of route request packets RREQ, the metric M2 included in the received plurality of route request packets RREQ is updated and updated. The route having the smallest metric M2 is determined as the route between the transmission source and the transmission destination.

  Further, a route between the transmission source and the transmission destination is determined based on the metric M2, and wireless communication is performed between the transmission source and the transmission destination, and the communication quality is lower than the threshold value. When the IP module 186A of the wireless device 3 newly receives a plurality of route request packets RREQ, the IP module 186A updates the metric M1 included in the received plurality of route request packets RREQ, and the updated metric M1 is the smallest. Is determined as a route between the transmission source and the transmission destination.

  The route response packet RREP consists of [rrep / destination 1 / source 1 / metric M1 / metric M2 / hop count / source 2], and the destination wireless device 3 determines the route based on the metric M1. In this case, the metric M1 of the route response packet RREP is updated at any time and transmitted to the transmission source wireless device 1, and the metric M2 of the route response packet RREP is determined when the transmission destination wireless device 3 determines a route based on the metric M2. Is updated from time to time and transmitted to the wireless device 1 as the transmission source.

In Embodiment 2, when the distance r between two adjacent wireless devices approaches the distance r _ds where the received signal strength RRSI is lower than the threshold value Prth, the distance r between the two adjacent wireless devices becomes the distance r. A route may be selected based on the metric M1 determined accordingly.

For example, when wireless communication is performed between the wireless device 1 and the wireless device 3 using a route including the wireless device 1 -the wireless device 4 -the wireless device 7 -the wireless device 3, the IP module of the wireless device 4 186A, when the distance r between the wireless device 4 through wireless device 7 approaches the distance r _ds, select the path based on the metric M1, relaying packets from the wireless device 1 to wireless device 2. That is, the path composed of the wireless device 1 -the wireless device 4 -the wireless device 7 -the wireless device 3 is switched to the route composed of the wireless device 1 -the wireless device 4 -the wireless device 2 -the wireless device 7 -the wireless device 3.

  In this case, the number of hops increases by “1 hop”, but a decrease in packet transfer rate is suppressed, so that a decrease in wireless communication throughput is suppressed.

Further, in the second embodiment, the total metric M _Total is calculated using the expression (1) in the first embodiment, and a route that minimizes the calculated total metric M _Total is determined between the transmission source and the transmission destination. It may be determined as a route.

In this case, the route request packet RREQ includes [rreq / source / total metric M _Total / destination], and the route response packet RREP includes [rrep / destination 1 / source 1 / total metric M _Total / hop count]. / Source 2].

Each wireless device 2,4～8 calculates the total metric _{M Total} according to equation (1), and updates the total metric _{M Total} of the route request packet RREQ or route reply packet RREP by the computed overall metric _{M Total} The route request packet RREQ or the route response packet RREP is relayed.

In addition, the transmission destination wireless device 3 determines a route having the minimum total metric M _Total as a route between the transmission source and the transmission destination in a plurality of route request packets RREQ received from a plurality of routes.

  In the second embodiment, each of the wireless devices 1 to 8 generally receives the link state packet LSP from n (n is a positive integer) wireless devices adjacent to the wireless devices 1 to 8 and receives the link state packet LSP. N distances from the wireless device are calculated.

  Then, when each of the wireless devices 1 to 8 receives the route request packet RREQ, the metric M1 (or metric M2) corresponding to the distance from the wireless device that has transmitted the route request packet to itself is used as the route request packet RREQ. The route request packet RREQ is updated by adding to the included metric, and the updated route request packet RREQ is broadcast.

  Considering the wireless device 1 that is a transmission source as a reference, n wireless devices 1 and n wireless devices adjacent to the wireless device 1 (= wireless devices 22, 4, 5, and 8). The distance is calculated, and the calculated n distances are converted into n metrics M1 according to Table 2. In addition, two wireless devices adjacent to each other in a plurality of wireless devices including m wireless devices (= wireless devices 3, 6, and 7) present at a position of 1 hop or more from the wireless device 1 and n wireless devices. K distances which are distances between them are calculated, and the calculated k distances are converted into k metrics M1 with reference to Table 2. Then, based on the n metrics M1 and k metrics M1, the route having the minimum sum of the metrics M1 when the route request packet RREQ is transmitted from the transmission source to the transmission destination is from the transmission source to the transmission destination. It is determined as a route.

  Therefore, each of radio apparatuses 1 to 8 according to the second embodiment is determined based on n metrics M1 and k metrics M1 and has a minimum total sum of metrics M1 (= stability level). Wireless communication is performed with a transmission destination along a relatively large route.

  In the first and second embodiments described above, each of the wireless devices 1 to 8 measures its own position with the D-GPS receiver 14 and includes the measured own position in the link state packet LSP or the Hello packet HLP. To the adjacent wireless device.

  That is, each of the wireless devices 1 to 8 transmits its own position determined by the longitudes and latitudes λ and φ of the measured GPS data to the adjacent wireless device. Therefore, it is possible to reduce a load on the wireless communication network 10 and determine a route for performing wireless communication between the transmission source and the transmission destination as compared with the case where the entire GPS data is transmitted to the adjacent wireless device.

  In the above description, α = 1, β = 1/10, and γ = 1/5. However, the present invention is not limited to this, and each of α, β, and γ Other values may be used.

  In the present invention, the metric M2 may be obtained using the frame error rate FER instead of the received signal strength RSSI. FIG. 28 is a conceptual diagram for explaining a method of calculating the frame error rate FER. The wireless device A transmits the communication request packet RTS to the wireless device B at the timing t1, sets a fixed time CTS_timer simultaneously with the transmission of the communication request packet RTS, and increments the communication count TransmitCnt by “1”. Then, the wireless device B receives the communication request packet RTS from the wireless device A at timing t2, and transmits a communication permission packet CTS for the communication request packet RTS to the wireless device A at timing t3. Then, the wireless device A receives the communication permission packet CTS from the wireless device B at timing t4.

  When the wireless device A receives the communication permission packet CTS from the wireless device B within the predetermined time CTS_timer, the wireless device A does not count the communication error number FailCnt and does not receive the communication permission packet CTS from the wireless device B within the predetermined time CTS_timer. In this case, the number of communication errors FailCnt is incremented by “1”.

  When the wireless device A receives the communication permission packet CTS from the wireless device B within the predetermined time CTS_timer, the wireless device A transmits the data DATA to the wireless device B at the timing t5 and sets the fixed time ACK_timer simultaneously with the transmission of the data DATA. In addition, the transmission count TransmitCnt is incremented by “1”. Then, the wireless device B receives the data DATA from the wireless device A at timing t6 and transmits an acknowledgment packet ACK for the data DATA to the wireless device A at timing t7. Then, the wireless device A receives the acknowledgment packet ACK from the wireless device B at timing t8.

  When the wireless device A receives the acknowledgment packet ACK from the wireless device B within the ACK_timer for a certain time, the wireless device A does not count the communication error number FailCnt and does not receive the acknowledgment packet ACK from the wireless device B within the ACK_timer for the certain time. In this case, the number of communication errors FailCnt is incremented by “1”.

  When the wireless device A does not receive the communication permission packet CTS from the wireless device B within the predetermined time period CTS_timer, the wireless device A starts again from the transmission of the communication request packet RTS, and counts the communication count TransmitCnt and the communication error count FailCnt.

  The wireless device A repeatedly receives the CTS packet for the communication request packet RTS and the acknowledgment packet ACK for the data DATA for a predetermined number of times. When the communication number TransmitCnt reaches the predetermined number, the frame error rate FER is calculated by the following equation. Calculate.

FER = FailCnt / TransmitCnt (2)
Each of the wireless devices 1 to 8 counts the communication count TransmitCnt and the communication error number FailCnt by the same operation as the wireless device A, and uses the counted communication count TransmitCnt and communication error number FailCnt to calculate the frame error rate by the equation (2). Calculate FER.

  In this case, the MAC module 113 of each of the wireless devices 1 to 8 measures the time with a timer (not shown) simultaneously with the transmission of the communication request packet RTS or the data DATA.

  In each of the wireless devices 1 to 8, the MAC module 113 calculates the frame error rate FER by the method described above, and transmits the calculated frame error rate FER to the operation device 18 via the wired interface 116 and the cable 17.

  In each of the wireless devices 1 to 8, the routing daemon 190 receives the frame error rate FER from the MAC module 113, and converts the received frame error rate FER into a metric M 2 with reference to Table 4.

  When the frame error rate FER is lower than 0.1, the metric M2 is “1”, and when the frame error rate FER is in the range of 0.1 ≦ FER <0.2, the metric M2 is “2”. When the frame error rate FER is in the range of 0.2 ≦ FER <0.3, the metric M2 is “3”, and when the frame error rate FER is in the range of 0.3 ≦ FER <0.4, When the metric M2 is “4” and the frame error rate FER is in the range of 0.4 ≦ FER <0.5, the metric M2 is “5” and when the frame error rate FER is 0.5 or more. The metric M2 is “6”.

  Accordingly, in each of the wireless devices 1 to 8, when receiving the frame error rate FER from the MAC module 113, the routing daemon 190 detects the metric M2 corresponding to the received frame error rate FER with reference to Table 4, The detected metric M2 is stored to create a routing table 187A (or 187B).

  Thus, the metric M2 stores a relatively small numerical value when the frame error rate FER is relatively low, and stores a relatively large numerical value when the frame error rate FER is relatively high.

  The frame error rate FER may be converted into the metric M2 according to Table 5.

  When the frame error rate FER is lower than 0.1, the metric M2 is “1”, and when the frame error rate FER is in the range of 0.1 ≦ FER <0.2, the metric M2 is “2”. When the frame error rate FER is in the range of 0.2 ≦ FER <0.3, the metric M2 is “4”, and when the frame error rate FER is in the range of 0.3 ≦ FER <0.4, When the metric M2 is “8” and the frame error rate FER is in the range of 0.4 ≦ FER <0.5, the metric M2 is “16” and when the frame error rate FER is 0.5 or more. The metric M2 is “32”.

  Therefore, according to Table 5, as the frame error rate FER increases linearly, the metric M2 increases by a power of 2. That is, as the frame error rate FER increases linearly, the metric M2 increases exponentially.

  Thus, by increasing the metric M2 as the path stability index exponentially as the frame error rate FER increases linearly (that is, as the frame error rate FER decreases linearly, By making the metric M2 exponentially small), a path with a greater degree of stability can be easily selected. The reason is the same as the reason for converting the distance r into the metric M1 so that the metric M1 changes exponentially as the distance r between two adjacent wireless devices changes linearly.

  In the above description, it has been described that the frame error rate FER is calculated and the calculated frame error rate FER is converted into the metric distance r according to Table 4 or Table 5. However, the present invention is not limited to this, and the frame error rate FER is not limited thereto. Instead of packet error rate PER (Packet Error Ratio), signal-to-noise ratio SNR (Signal to Noise Ratio), signal power, bit error rate, carrier signal-to-noise ratio, and noise ratio including interference noise to signal May be used.

  The packet error rate PER is represented by a ratio of the number of packets in which a CRC (Cyclic Redundancy Check) error has occurred to the total number of packets transmitted and received. Therefore, the packet error rate PER is calculated by the MAC module 113 and transmitted to the routing daemon 190 by the MAC module 113.

  The signal-to-noise ratio SNR is represented by the ratio of noise intensity to signal intensity. Accordingly, the signal-to-noise ratio SNR is calculated by the wireless interface module 112 and transmitted to the routing daemon 190 by the wireless interface module 112.

  Furthermore, the signal power represents the power of the received signal. Accordingly, the signal power is detected by the wireless interface module 112 and transmitted to the routing daemon 190 by the wireless interface module 112.

  Further, the bit error rate represents the error rate of the demodulated bits. Accordingly, the bit error rate is detected by the wireless interface module 112 and transmitted to the routing daemon 190 by the wireless interface module 112.

  Further, the carrier signal to noise ratio represents the ratio of noise to the carrier signal. Accordingly, the carrier signal to noise ratio is detected by the wireless interface module 112 and transmitted by the wireless interface module 112 to the routing daemon 190.

  Further, the noise ratio including interference noise to the signal represents [noise including interference noise] / signal intensity. Therefore, a noise ratio including interference noise for the signal is detected by the wireless interface module 112 and transmitted to the routing daemon 190 by the wireless interface module 112.

  Then, each of the packet error rate PER, the signal-to-noise ratio SNR, the signal power, the bit error rate, the carrier signal-to-noise ratio, and the noise ratio including interference noise for the signal is converted into the metric M2 according to Table 4 or Table 5. The

In each wireless device 1-8, the routing daemon 190 substitutes the metric M2 determined using the frame error rate FER, the packet error rate PER, etc. into the equation (1) to obtain the total metric M _Total and obtains the routing table 187A. (Or 187B) is completed.

  In the present invention, the received signal strength, the frame error rate FER, the packet error rate PER, the signal-to-noise ratio SNR, the bit error rate, the carrier signal-to-noise ratio, and the noise ratio including the interference noise for the signal are Table 3 shows each of the received signal strength, frame error rate FER, packet error rate PER, signal-to-noise ratio SNR, bit error rate, carrier signal-to-noise ratio, and noise ratio including interference noise for the signal. The metric M2 obtained with reference to Table 5 constitutes a “route quality indicator”.

  Further, the metric M1 constitutes a “path stability index”.

  Further, in the present invention, the routing daemon 190 that creates the routing tables 187, 187A, and 187B and the IP modules 186 and 186A that determine the route to the destination based on the routing tables 187, 187A, and 187B Means ".

  Furthermore, in the present invention, the IP module 186 and the wireless LAN terminal 11 that transmit a frame along the determined path constitute a “communication unit”.

  Furthermore, in the present invention, the D-GPS receiver 14 GPS antenna 15 and FM antenna 16 constitute “position detecting means”, and the wireless LAN terminal 11 and array antenna 12 constitute “receiving means”.

  Furthermore, in the present invention, the routing daemon 190 that calculates the distance r between two adjacent wireless devices constitutes a “distance calculation means”.

  Further, in the present invention, the routing daemon 190 that converts the distance r into the metric M1 with reference to Table 2, or the received signal strength RSSI, the frame error rate, the packet error rate, the signal-to-noise ratio SNR, the signal power, and the bit error The routing daemon 190 that converts each of the ratio, the carrier signal-to-noise ratio, and the noise ratio including the interference noise to the signal into the metric M2 with reference to any one of Tables 3 to 5 constitutes “path index calculation means” To do.

  Further, in the present invention, the MAC module 113 for detecting the packet error rate PER or the MAC module 113 for calculating the frame error rate constitutes “quality detection means”. The radio interface module 112 that detects each of the received signal strength RSSI, the signal-to-noise ratio SNR, the signal power, the bit error rate, the carrier signal-to-noise ratio, and the noise ratio including interference noise with respect to the signal is “quality detection means”. Is configured.

  The relationship between received signal strength and distance shown in FIG. 21 constitutes a “distance / quality table”, and the routing table 190 that holds the relationship between received signal strength and distance shown in FIG. 21 constitutes “holding means”. To do.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and is intended to include meanings equivalent to the scope of claims for patent and all modifications within the scope.

  The present invention is applied to a wireless device that suppresses a load on a network and can stably obtain a high throughput. In addition, the present invention is applied to a wireless communication network including a wireless device that can suppress a load on the network and stably obtain a high throughput.

It is the schematic of the radio | wireless communication net arc by embodiment of this invention. FIG. 2 is a schematic block diagram in the first embodiment showing the configuration of the wireless device shown in FIG. 1. It is the schematic which shows the structure of the wireless LAN terminal shown in FIG. 2, an array antenna, and an operating device. FIG. 3 is a plan view of the array antenna shown in FIG. 2 in an xy plane. It is a block diagram of a link state packet. It is a figure which shows the example of the routing table shown in FIG. FIG. 7 is a first diagram for explaining a method of creating the routing table shown in FIG. 6. FIG. 7 is a second diagram for explaining a method of creating the routing table shown in FIG. 6. It is a figure which shows the example of the address conversion table shown in FIG. It is a block diagram of a wired frame. It is the schematic which shows the structure of the acquisition request signal of GPS data. It is the schematic which shows the structure of the response signal with respect to the acquisition request signal of GPS data. It is a figure which shows the format of GPT1 shown in FIG. It is a figure which shows the structure of GPS data shown in FIG. It is a block diagram of radio | wireless frame RFF. It is a conceptual diagram which shows conversion between the wired frame WIRF and the radio | wireless frame RFF. It is a figure which shows the example of the routing table using the metric determined according to the received signal strength. FIG. 18 is a diagram for explaining a method of creating the routing table shown in FIG. 17. It is a timing chart of a packet transfer rate and the number of hops. It is another timing chart of a packet transfer rate and the number of hops. It is a figure which shows the relationship between the received signal strength and distance in a multipath environment. It is another example of a routing table. It is a figure which shows the structure in Embodiment 2 of the radio | wireless apparatus shown in FIG. It is a block diagram of a Hello packet. 10 is a diagram for explaining a method for establishing a route to a transmission destination in Embodiment 2. FIG. It is a further timing chart of a packet transfer rate and the number of hops. It is another timing chart of a packet transfer rate and the number of hops. It is a conceptual diagram for demonstrating the method of calculating a frame error rate.

Explanation of symbols

    1 to 8 wireless device, 10 wireless communication network arc, 11 wireless LAN terminal, 11A, 11B FCS, 12 array antenna, 12A, 12B frame main body, 13, 17, 20 cable, 13A data type, 13B PAD, 14 D-GPS Receiver, 14A source address, 14B 802.2 SNAP, 15 GPS antenna, 15A destination address, 15B 802.2 LLC, 16 FM antenna, 16B IEEE 802.11 MAC header, 18, 18A operating device, 19 maintenance device, 110 GPS drive , 111 antenna control module, 112 wireless interface module, 113 MAC module, 114 address conversion table, 115 LLC module, 116, 185 wired interface, 181 Input unit, 182 display unit, 183 e-mail application, 184, 184A communication control unit, 186, 186A IP module, 187, 187A, 187B routing table, 188 TCP module, 189 UDP module, 190 routing daemon, 191 SMTP module.

Claims (6)

A wireless device that is autonomously established and constitutes a wireless communication network in which wireless communication is performed between a transmission source and a transmission destination,
Position detecting means for detecting first position information indicating the position of the wireless device;
Receiving means for receiving n second position information indicating the positions of n (n is a positive integer) adjacent wireless devices adjacent to the wireless device from the n adjacent wireless devices;
Distance calculating means for calculating n distances between the wireless device and the n adjacent wireless devices based on the first position information and the n second position information;
communication means for performing the wireless communication along a suitable path determined based on k (k is a positive integer) distance and the n distances and having a relatively high degree of stability;
Each of the k distances is m (m is a positive integer) wireless devices capable of wireless communication with the wireless device using any one of the n adjacent wireless devices as a repeater. And a distance between two adjacent wireless devices in a plurality of wireless devices composed of the n adjacent wireless devices. The preferred path is determined based on k + n path stability indices;
2. The radio apparatus according to claim 1, wherein each of the k + n path stability indicators indicates a degree of path stability and is calculated based on each of the k distances or each of the n distances. . Route index calculation means for calculating the n path stability indexes based on the n distances;
Route determining means for determining, as the preferred route, a route having a minimum sum of route stability indicators to the destination based on the k + n route stability indicators;
The receiving means further receives the k route stability indicators from at least one of the n neighboring radio devices, and outputs the received k route stability indicators to the route determining means;
The wireless device according to claim 2, wherein the communication unit performs the wireless communication along a preferable route determined by the route determination unit.   The preferable route has a minimum total route stability index that is a total sum of the route stability degrees when a route request packet for requesting establishment of a route from the transmission source to the transmission destination is transmitted to the transmission destination. The wireless device according to claim 2, comprising a route.   When the wireless device is a repeater that relays the wireless communication between the transmission source and the transmission destination, when the wireless device receives the route request packet, the communication unit is included in the received route request packet 5. The comprehensive route stability index is updated and relayed, and a route response packet, which is a response to the route request packet, is relayed along the suitable route to a wireless device existing on the source side or the source side. A wireless device according to 1. A wireless communication network that is autonomously established and performs wireless communication between a transmission source and a transmission destination,
A plurality of wireless devices,
6. The wireless communication network, wherein the plurality of wireless devices include the wireless device according to any one of claims 1 to 5.