JP4094577B2 - Wireless communication apparatus, wireless communication system, wireless communication program, recording medium - Google Patents

Description

  The present invention relates to a radio communication apparatus having a function of suppressing radio wave interference and coexisting networks in an environment where a plurality of networks formed by a radio communication apparatus serving as a master station and a plurality of radio communication apparatuses serving as slave stations exist. It is about.

  By connecting a plurality of computers and constructing a LAN (Local Area Network), it is possible to share files and data, share peripheral devices such as printers, and transfer contents to each other.

  However, conventionally, in order to construct a LAN, it has been common to connect each device in a wired manner using a twisted pair cable or the like. Therefore, when LAN is introduced, there are complicated aspects such as laying lines and routing cables. There were many. Moreover, since the movement range of the apparatus after installation is also restricted by the cable length, it is very inconvenient.

  In order to solve such problems, a wireless LAN in which devices are connected by wireless communication has been proposed and put into practical use. This makes it possible to move the devices in the LAN to some extent even after the LAN is built in the home or office. In addition, it is easy to add wireless devices to the LAN.

  In addition, since the wireless LAN uses a frequency band that does not require a license, such as a 2.4 GHz band or a 5 GHz band, as a frequency band used for communication, it can be introduced relatively easily. Further, in recent years, the spread of wireless LAN has been explosively progressing due to the high speed and low price of wireless LAN.

  Further, UWB (Ultra Wideband) has been developed as one of wireless communication technologies used for wireless PAN (Personal Area Network) and the like. This has a feature that data communication can be performed at a very high speed in a short distance. UWB, for example, performs data communication by spreading to a very wide frequency band of 3.1 GHz to 10.6 GHz, and the data transmitted in each frequency band has only the strength of noise, so the same. There are advantages such as no interference with other wireless devices using the frequency band and low power consumption.

  In addition to communication, the UWB can be used as position measurement or radar. The position measurement function of UWB can be measured more accurately than GPS, and is applied to a device that informs an accurate distance from a golf tee to a hole. In addition, the UWB radar function is considered to be used for lifesaving and home security at accident sites.

  On the other hand, with regard to UWB communication functions, a communication speed of several hundreds of Mbps can be achieved as long as the distance is several meters, so the wireless version of USB (Universal Serial Bus) 2.0 and the wireless connection of high-definition home AV equipment, etc. Those that are short-distance but require large-capacity transfer are considered as usage scenes.

  As UWB communication methods, a multiband OFDM (Orthogonal Frequency Division Multiplexing) method using frequency hopping, a CDMA (Code Division Multiple Access) method, and the like have been proposed.

  For example, in the case of the multiband OFDM scheme, the frequency band to be used is divided into several subbands, and communication is performed using frequency hopping. In the proposed specification, the frequency channel is divided into three channels, and multiple access is made possible by using four types of frequency hopping patterns (see FIG. 24) that are combined.

  In the case of the CDMA system, multiple access is made possible by spreading codes, and in the proposed specification, four types of spreading code patterns (see FIG. 25) are used to enable four communications simultaneously. Yes.

  Further, IEEE 802.15.3 MAC has been proposed as a standard used when constructing a network using UWB. In the IEEE 802.15.3 MAC, a wireless control device called PNC (Piconet Coordinator) transmits a beacon at a constant cycle, and a plurality of DEVs (Devices) composed of wireless communication devices that have received the beacon and a network called a piconet Form. In this piconet, a beacon period is defined as a transmission frame period, and a time slot used by each wireless communication apparatus is assigned for each transmission frame period. According to the assigned time slot, the PNC and each DEV communicate.

  However, in this IEEE802.15.3 MAC, when the same frequency hopping pattern or spreading code pattern is used when a DEV enters a part where communication ranges of a plurality of PNCs overlap, radio interference occurs. Communication may not be possible.

  A method for solving the problem of radio wave interference as described above is proposed in Patent Document 1 (Japanese Patent No. 3382806), Patent Document 2 (Japanese Patent No. 3349861), and the like.

  Patent Document 1 automatically detects movement of the own station and interference between a plurality of wireless sub-networks by transmitting and receiving control packets between a plurality of parent wireless stations and a child wireless station. Based on the channel change setting, interference when a DEV enters a part where communication ranges of a plurality of PNCs overlap is prevented.

  Further, in Patent Document 2, in a wireless LAN composed of a plurality of wireless networks managed by a parent station, information on used channels is exchanged between the parent stations, and the parent station efficiently uses channels that are not used in the surroundings. Select to prevent radio wave collision. In addition, radio waves collide with hidden terminals by preventing the use of the same channel by listing the used channels.

Thereby, also in patent document 2, the interference when DEV enters into the part with which the communication range of several PNC overlaps is prevented.
Patent No. 3382806 (issued March 4, 2003) Japanese Patent No. 3349861 (issued on November 25, 2002)

  However, in Patent Document 1, even when a plurality of other networks exist adjacent to the network that has transmitted the control packet, even if interference at one location can be avoided by changing the communication control information, There is a possibility that new interference may occur in another place due to the communication control information changed by the avoidance.

  Further, in Patent Document 2, the master stations are connected with each other by wire, and exchange of information for avoiding interference is performed by communication between the master stations. For this reason, for example, when the master stations are connected by radio instead of wired, there is a possibility that the master stations cannot communicate with each other depending on the distance. In such a case, there arises a problem that control for avoiding interference cannot be performed well.

  Therefore, in Patent Documents 1 and 2, when a new communication device enters a part where communication ranges of a plurality of networks overlap, there is a possibility that interference cannot be avoided and communication cannot be performed reliably. Also occurs.

  The present invention has been made in view of the above-described problems, and the object thereof is to reliably avoid interference when a new communication device enters a portion where communication ranges of a plurality of networks overlap. An object of the present invention is to provide a wireless communication apparatus and a wireless communication system capable of reliably performing communication.

  In order to solve the above problems, a wireless communication apparatus according to the present invention classifies communication methods for separating signals in advance and sets them as a plurality of different communication control information when performing multiple access. In accordance with one of the communication control information specified by a station, a wireless communication device that is a slave station in a communication system that performs communication, and when the communication control information received from a plurality of master stations matches, Based on the type of communication control information used in other networks that overlap the station and communication range, the number of other networks that overlap the communication range with each master station, and the identification number of the master station in each network A change destination determining means for determining a change destination master station of the communication control information, and a parent station of a network whose communication range overlaps with a master station other than the change destination parent station determined by the change destination determination means. Communication control information determining means for determining the communication control information to be changed based on either the identification number of the communication control information that is present and the type of communication control information of another network whose communication range overlaps with each master station It is characterized by that.

  According to the above configuration, when communication control information received from a plurality of master stations matches, first, the type of communication control information, the number of other networks that overlap each master station and the communication range, Based on the identification number of the master station, the master station to which the communication control information is changed is determined, and then the master station of the network whose communication range overlaps with the master station other than the determined master station to be changed is managed. Each master station by determining the communication control information to be changed based on either the identification number of the communication control information being managed and the type of communication control information of another network whose communication range overlaps with each master station. The communication control information of the master station in a state where the communication control information matches can be changed in consideration of the communication control information used in other networks with which the communication ranges overlap.

  Therefore, it is possible to eliminate interference in a network whose communication control information matches at the present time and to avoid occurrence of interference in a network formed by a parent station other than the determined parent station.

  As a result, even when a new communication device enters a part where communication ranges of a plurality of networks overlap, it is possible to reliably avoid interference and perform wireless communication reliably in each network. There is an effect that a communication device can be provided.

  In addition, in order to solve the above-described problem, the wireless communication device of the present invention classifies communication methods for separating signals in advance and sets them as a plurality of different communication control information when performing multiple access. In accordance with one of the communication control information specified by the master station, the radio communication device is a master station in the communication system that performs communication, the communication control information managed by the own radio communication device, and other If the communication control information received from the master station matches, the type of communication control information used in the other network where the communication range overlaps with each parent station, and the other network where the communication range overlaps with each parent station A change destination determination unit that determines a change destination parent station of the communication control information based on either the number and the identification number of the parent station of each network, and the change destination parent station determined by the change destination determination unit Other than Change based on the identification number of the communication control information managed by the master station of the network whose communication range overlaps with the station, and the type of communication control information of other networks whose communication range overlaps with each master station Communication control information determining means for determining communication control information is included.

  According to the above configuration, when the communication control information managed by the own wireless communication device matches the communication control information received from another master station, first, the type of communication control information and each master station Based on the number of other networks whose communication ranges overlap each other and the identification number of the master station of each network, and then determine the master station to which the communication control information is to be changed, and then the determined master station to be changed Based on the identification number of the communication control information managed by the master station of the network whose communication range overlaps with the other master station and the type of communication control information of the other network whose communication range overlaps with each master station By determining the communication control information to be changed, the communication control information of the master station in a state where the communication control information is matched in consideration of the communication control information used in other networks where the communication ranges of the respective master stations overlap. Can be changed

  Therefore, it is possible to eliminate the interference in the network whose communication control information matches at the present time and to avoid the occurrence of the interference in the network formed by the other master station.

  As a result, even when a new communication device enters a part where communication ranges of a plurality of networks overlap, it is possible to reliably avoid interference and perform wireless communication reliably in each network. There is an effect that a communication device can be provided.

  The radio communication apparatus according to the present invention preferably further includes communication control information changing means for changing the communication control information currently managed to the communication control information determined by the communication control information determining means.

  By having the communication control information changing means described above, the communication control information can be changed with certainty, so that there is an effect that interference can be avoided more reliably.

  Further, in the wireless communication apparatus according to the present invention, the type of the communication control information, the number of other networks whose communication ranges overlap with each parent station, and the identification number of the parent station of each network can be rewritten as list information. A list information storing means for storing and a list information rewriting means for rewriting the list information based on the changed communication control information when the communication control information is changed by the communication control changing means; As a result, it becomes easy to associate the symmetrical communication control information rewritten in the master station with other information, and as a result, it is possible to easily control the avoidance of interference.

  Further, the change destination determination means may determine, as a change destination, a master station having the smallest type of communication control information used in another network having a communication range overlapping each parent station.

  Further, the change destination determination means may determine a parent station having the least number of other networks having a communication range overlapping each parent station as the change destination.

  In addition, the change destination determination means may determine, as a change destination, a master station selected by a master station identification number compared according to a predetermined rule among the master stations.

  Furthermore, the communication control information determining means may determine communication control information that is not used in another network whose communication range overlaps with the change-destination master station as communication control information to be changed.

  Further, the communication control information determining means is a communication control for changing communication control information that is most frequently used among types of communication control information used in other networks whose communication range overlaps with a master station that is not a change destination. It may be determined as information.

  Further, the communication control information determining means is changed according to the identification number of the communication control information compared according to a predetermined rule among the communication control information used in another network whose communication range overlaps with the master station that is not the change destination. Communication control information to be determined may be determined.

  The communication control information may be a frequency hopping pattern used in a frequency hopping method.

  Further, the communication control information may be a spreading code pattern used in a CDMA (Code Division Multiple Access) system.

  As described above, when the communication control information received from a plurality of parent stations matches, the wireless communication device according to the present invention is the communication control information used in another network that overlaps each parent station and the communication range. A change destination determination means for determining a change destination parent station of communication control information based on any of the type, the number of other networks whose communication range overlaps with each parent station, and the identification number of the parent station of each network And the identification number of the communication control information managed by the master station of the network whose communication range overlaps with the master station other than the change-destination master station determined by the change destination determination means, Communication control information determining means for determining communication control information to be changed based on any of the types of communication control information of the network, so that a new communication device can be added to a portion where communication ranges of a plurality of networks overlap. three Even when the have, interference can be reliably prevented, an effect that it is possible to perform communication securely in each network.

  An embodiment of the present invention will be described as follows. In the present embodiment, a radio communication system composed of a master station as a radio communication device and a slave station that performs communication according to communication control information specified by the master station will be described.

  The radio communication system according to the present embodiment includes a slave station 100 shown in FIG. 1 (a) and a master station 200 shown in FIG. 1 (b). Note that the wireless communication system performed between the slave station 100 and the master station 200 uses a multiband OFDM system compliant with IEEE 802.15.3 MAC. This multiband OFDM method is a communication method in which a frequency band is divided into several subbands and communication is performed using frequency hopping.

  As shown in FIG. 1A, the slave station 100 includes a change destination determination unit 101, a communication control information determination unit 102, an information storage unit 103, a control unit 104, a communication control information (pattern) comparison unit 105, and a transmission unit. 106, a receiving unit 107, and an antenna 108.

  That is, in the slave station 100 having the above configuration, the control unit 104 operates according to a program stored in the information storage unit 103. That is, the signal from the antenna 108 is processed by the receiving unit 107, and the communication control information comparing unit 105, the change destination determining unit 101, and the communication control information determining unit 102 are respectively processed according to the received contents, and the transmitting unit 106 is connected to the antenna 108. Send the signal through.

  The change destination determination unit 101 examines a list (described later) from a plurality of parent stations 200 received through the antenna 108, and determines two or more same communication control information to determine the parent station 200 to communicate with. I'm about to do it.

  The communication control information determination unit 102 determines communication control information with the communication destination master station 200 determined by the change destination determination unit 101.

  The information storage unit 103 stores a program and processing data for executing processing in the change destination determination unit 101, the communication control information determination unit 102, and the like.

  The control unit 104 controls each unit.

  The communication control information comparison unit 105 compares the communication control information in the list.

  The transmitter 106 is where the slave station 100 transmits data to the outside.

  The receiving unit 107 receives data from the outside at the slave station 100.

  The antenna 108 is a member used when the transmission unit 106 and the reception unit 107 transmit and receive data.

  The master station 200 includes a communication control information determination unit 202, a change destination determination unit 201, a list storage unit 203, an information storage unit 204, a control unit 205, a list processing unit 206, as shown in FIG. A transmission unit 207, a communication control information control unit 208, a reception unit 209, and an antenna 210 are included.

  That is, in the master station 200 configured as described above, the control unit 205 operates according to a program stored in the information storage unit 204. In addition, information about itself and peripheral networks is stored in the list storage unit 203 as list information. The signal from the antenna 210 is processed by the reception unit 209, and the communication control information determination unit 202, the change destination determination unit 201, the communication control information control unit 208, and the list processing unit 206 are respectively processed according to the received content, and the transmission unit 207 Transmits a signal through the antenna 210.

  The change destination determination unit 201 receives a list from another master station 200, and when there are two or more same communication control information, examines the same list of communication control information, and determines the master station to be a communication partner. 200 is about to be decided.

  The communication control information determination unit 202 determines communication control information with the communication destination master station 200 determined by the change destination determination unit 201.

  The list storage unit 203 stores a list as shown in FIG.

  In the above list, as shown in FIG. 2, the local station identification number composed of the PNC ID number, the communication control information used in the local network, and the update identifier indicating whether or not the list to be transmitted has been updated. Further, as the information regarding the adjacent network, the adjacent master station identification number and the communication control information used in the adjacent network are described and read out as necessary.

  In addition, about the information regarding said adjacent network, only the part for an adjacent network is described. In addition, when a new network is adjacent, information on the network is added to the list. These processes are performed in the list processing unit 206.

  The information storage unit 204 stores a program for executing processing in the change destination determination unit 201 and the communication control information determination unit 202 and data for processing.

  The control unit 205 controls each unit.

  The list processing unit 206 performs processing such as addition and deletion of a list on the list stored in the list storage unit 203 or the stored list.

  The transmission unit 207 transmits data to the outside in the master station 200.

  The communication control information control unit 208 controls communication control information in the network.

  The receiving unit 209 is where the master station 200 receives data internally.

  The antenna 210 is a member used when the transmission unit 207 and the reception unit 209 transmit and receive data.

  In IEEE802.15.3 MAC, a radio control device called PNC (Piconet Coordinator) (corresponding to the master station 200) and a plurality of DEVs (Devices) that transmit beacons at a constant cycle and receive the beacons. ) (Corresponding to the slave station 200) to form a network called a piconet.

  By the way, in the multiband OFDM system employed in the present embodiment, the frequency hopping pattern (communication control information) used for communication is limited. Therefore, when there are a plurality of networks in the vicinity, the communication control information is allocated successfully. Otherwise, the communication control information will be insufficient, and interference will not be avoided. For example, as shown in FIG. 3, when there are four types of communication control information, there may be a shortage of communication control information when four piconets are adjacent to each other. On the other hand, if it can be assigned well, it is possible to perform communication properly without interference even if only four pieces of communication control information are used, as shown in FIG. 4, even if four or more networks are adjacent to each other. .

  Here, a large circle in the figure indicates a communication range of each parent station, and a small circle at the center of the circle indicates a parent station and a small square indicates a child station. An adjacent network is said to be adjacent when there are a plurality of networks and when another communication device exists in a portion where communication ranges overlap. For example, FIG. 4 shows that network 1 and network 2 are adjacent, but network 3 and network 4 are not adjacent.

  The present invention refers to a list in which information of networks adjacent to a parent station is periodically transmitted from the parent station when a plurality of networks are adjacent to each other. Check if control information is used to cause interference. If the same communication control information is used, it is necessary to change to use different communication control information and avoid interference, so determine the change destination of the communication control information and the communication control information to be changed. .

  The change destination of the communication control information is determined by the following algorithm.

  The master station having the smaller network type whose communication range overlaps with each network having the same communication control information is determined as the change destination. If the types are the same, the smaller number of networks whose communication ranges overlap each network is determined as the change destination. If the types and numbers are the same, the identification numbers of the master stations of the networks are compared according to a predetermined rule, and the smaller value is determined as the change destination here.

  Further, which communication control information is changed is determined by the following algorithm. Communication control information to be changed is determined from communication control information that is not used in a network whose communication range overlaps with the network to be changed. Further, among the types of communication control information used in a network whose communication range overlaps with a network other than the change destination, the most frequently used type is determined as communication control information to be changed. If the type is the same, the communication control information used in the network whose communication range overlaps with the network other than the change destination is compared according to a predetermined rule. In this case, the smaller value is the communication control information to be changed. Determine as.

  The master station that has completed the change of the communication control information updates the list and transmits the updated list to the surroundings. The slave station that has received the updated list relays the list toward the adjacent master station. The master station that has received the updated list refers to the list and updates its own list. In addition, the list includes an identifier that can identify whether the list is periodically transmitted or updated by changing the communication control information.

  From the above, the present invention intends to provide a wireless communication system capable of always ensuring an appropriate communication state by managing communication control information between adjacent networks.

  In this embodiment, since the multi-band OFDM method is adopted as the communication method as described above, PNC and DEV have three frequency channels, and four types of hopping patterns (pattern 1 to pattern 4) ( Using this as communication control information, communication is performed by frequency hopping.

  Here, the operation of each of the master station 200, the newly entered slave station 100, and the slave station 100 that has already communicated with the master station 200 will be described below with reference to the flowcharts shown in FIGS. To do.

  The operations of the master station 200, the slave station 100, and the newly entered slave station 100 in a state where a plurality of piconets composed of the master station 200 and the slave station 100 exist adjacent to each other are shown in FIGS. This will be described below with reference to the flowchart shown in FIG.

  Here, the newly entered slave station 100 is a slave station 100 newly arranged in an overlapping portion between piconets.

  The operation of the master station 200 will be described with reference to the flowchart shown in FIG.

  First, the master station 200 transmits the list shown in FIG. 2 (step S001). Next, the master station 200 determines whether a list from another master station 200 has been received (step S002). . If a list has been received, the process proceeds to step S003, and the list is examined. If the list has not been received, the process proceeds to step S011 to determine whether or not a change request has been received from the slave station 100.

  Subsequently, the master station 200 determines whether there are two or more identical communication control information as a result of examining the list (step S004). If there are two or more pieces of the same communication control information, the process proceeds to step S005 to check a list of the same communication control information. If there is no two or more same communication control information, the process proceeds to step S013 to update the list.

  Next, the master station 200 determines a change destination based on the result of examining the list (step S006). Details of the change destination determination process will be described later.

  Then, the master station 200 determines whether or not the determined change destination is itself (own station) (step S007). If it is determined that the change destination is not the user, the process proceeds to step S009 to determine whether an updated list is received. On the other hand, when it is determined that the change destination is itself, the process proceeds to step S008, and communication control information to be changed is determined. Details of the process for determining the communication control information to be changed will be described later.

  Thereafter, the process proceeds to step S012, and the current communication control information is changed to the determined communication control information.

  Further, when it is determined in step S011 that a change request has been received, the process proceeds to step S012, and the communication control information is changed.

  If it is determined in step S011 that a change request has not been received, the process proceeds to step S009 to determine whether an updated list has been received. At this time, if it is determined that the updated list has not been received, the process proceeds to step S001, and the list is transmitted again.

  If it is determined in step S009 that the updated list has been received, the list is updated (step S010), the process is terminated, and communication is started.

  On the other hand, after changing the communication control information in step S012, the list is updated (step S013), the updated list is transmitted (step S014), and the process is terminated. Then, communication is started.

  The operation of the newly-entered child station 100 will be described with reference to the flowchart shown in FIG.

  First, a list transmitted from the master station 200 is received (step S101), and it is determined whether there are a plurality of lists (step S102). If it is determined that there are not a plurality of lists, that is, only one list, communication with the master station 200 that has transmitted the list is started (step S108), and the process is terminated.

  On the other hand, if it is determined in step S102 that there are a plurality of lists, the list is examined (step S103), and it is determined whether there are two or more identical communication control information (step S104). Here, if there is no same communication control information, a list update request is made to the master station 200 (step S109), and the process proceeds to step S111.

  If it is determined in step S104 that there are two or more pieces of the same communication control information, a list of the same communication control information is checked (step S105), and a change destination determination process is performed (step S106). Then, after the change destination is determined, the communication control information to be changed is determined (step S107).

  Thereafter, a change request is transmitted to the master station 200 (step S110), the updated list is relayed (step S111), and the process ends.

  Here, relaying the updated list indicates the following contents. When the communication control information of a certain network is changed, the list held by the parent station of the network adjacent to the network must be updated as well as the list held by the parent station of the network is updated. This is because the list includes its own communication control information and communication control information of adjacent networks. Therefore, the master station whose communication control information has been changed updates the list, and relays the updated list to the neighboring master stations when the master stations cannot communicate directly with each other by relaying the neighboring slave stations. As a result, the list of adjacent master stations can be updated.

  That is, in the above step S111, after the change request is transmitted in step S110, channel change processing (S012) and list update processing (S013) are performed in the master station that has received the change request, and the updated list is transmitted to the surroundings. (S014). By transmitting (relaying) the updated list to the master station other than the change destination, the list of the master station other than the change destination can be updated.

  The operation of the slave station that is already communicating with the master station will be described below with reference to the flowchart shown in FIG.

  First, it is determined whether a list from the own master station is received (step S201). Here, if it is determined that the list from the master station has not been received, it is determined that communication with the master station has been interrupted (step S205), and the process proceeds to step S201 again.

  In step S201, when a list from the own parent station is received, the list is relayed to the surroundings (step S202), and it is determined whether a list from other than the own station is received (step S203). . If it is determined that a list from a station other than its own master station has been received, the process proceeds to step S103 in the flowchart showing the operation of the slave station that has newly entered, and processing is performed when interference occurs.

  On the other hand, if it is determined in step S203 that a list from a station other than its own master station has not been received, it is determined whether a change request has been received (step S206). If it is determined that the change request has been received, the change request is transmitted to the own master station (step S207), and the process proceeds to step S208.

  If it is determined in step S206 that a change request has not been received, the process proceeds to step S208 to determine whether an updated list has been received. If it is determined that the updated list has not been received, the process ends. If it is determined that the updated list has been received, the updated list is relayed (step S209), and the process ends.

  The change destination determination subroutine will be described below with reference to the flowchart shown in FIG. The change destination determination subroutine here is the same in the slave station 100 and the master station 200, and is executed by the change destination determination unit 101 in the slave station 100. In the master station 200, the change destination determination unit 201 is executed. Is executed.

  First, as a result of examining the same list of communication control information, it is determined whether or not there is a difference in the number of communication control information used by networks adjacent to each network (step S301). Here, when it is determined that there is a difference in number, a small number is selected (step S304), and the process is terminated.

  On the other hand, if it is determined in step S301 that there is no difference in number, it is further determined whether there is a difference in the number of networks adjacent to each network (step S302). Here, if it is determined that there is a difference in number, the process proceeds to step S304 and a small number is selected.

  If it is determined in step S302 that there is no difference in the number, the network station with a smaller master station ID number is selected (step S303), and the process is terminated.

  Next, a determination subroutine for communication control information to be changed will be described below with reference to the flowchart shown in FIG. The communication control information determination subroutine to be changed here is the same processing performed by the slave station 100 and the master station 200. In the slave station 100, the communication control information determination unit 102 executes the subroutine. It is executed by the communication control information determination unit 202.

  First, communication control information that is not used in a network adjacent to the change destination network is selected (step S401), and whether there is a difference in the number of communication control information used in a network adjacent to a network other than the change destination network. It is determined whether or not (step S402). If it is determined that there is a difference in number, a large number are selected (step S405), and the process ends.

  On the other hand, if it is determined in step S402 that there is no difference in the number, it is determined whether there is a difference in the number of communication control information numbers used by networks adjacent to the network other than the change destination (step S403). ). If it is determined that there is a difference in the number of communication control information numbers, the process proceeds to step S406 to select a small number of communication control information, and the process ends.

  If it is determined in step S403 that there is no difference in the number of numbers, the process proceeds to step S404, the one with the smallest communication control information number is selected, and the process ends.

  Hereinafter, in the wireless communication system having the above-described configuration, wireless communication control in an environment where a plurality of piconets exist will be described together with specific operations for each environment where the piconets exist.

  First, as shown in FIG. 10, there are five piconets (piconet 1 to piconet 5) in the space, PNC1 is DEV1-1 and DEV1-2 and pattern 1, PNC2 is DEV2 and pattern 1, and PNC3 is Assume that DEV3 and pattern 2, PNC4 communicate with DEV4 and pattern 3, and PNC5 communicate with DEV5-1, DEV5-2, and pattern 2, respectively. In this state, each piconet can communicate without causing interference.

  Here, let us consider a case where, in the piconet in the state shown in FIG. 10, DEV1-3 has newly entered a part where the communication ranges of PNC1 and PNC2 overlap as shown in FIG.

  In this case, since PNC1 and PNC2 perform communication using the same pattern 1, there is a possibility that interference may occur and communication cannot be performed as it is. Therefore, the pattern is changed to reduce interference. Specifically, the interference is reduced by changing the pattern 1 of the piconet 2 to the pattern 3 as shown in FIG.

  Regarding the flow of processing in this case, the flowchart shown in FIG. 5 showing the processing in the master station (PNC1, PNC2), the flowchart shown in FIG. 6 showing the processing in the newly entered slave station (DEV1-3), and the existing child This will be described below with reference to the flowchart shown in FIG. 7 showing the processing in the stations (DEV1-1, DEV1-2, etc.).

  First, PNC1 and PNC2 periodically transmit a list (step S001).

  On the other hand, DEV1-3 receives the lists from PNC1 and PNC2 (step S101), and determines whether there are a plurality of received lists (step S102). Here, since the PNC1 list and the PNC2 list are received, it is determined that a plurality of lists are received.

  Then, the DEV1-3 examines each received list (step S103). Thereafter, the DEV 1-3 checks which pattern is used in each PNC (step S104). Here, since both lists contain information that the pattern 1 is used, the pattern is changed.

  At the same time, PNC1 and PNC2 determine whether or not a list is received from another PNC (step S002). Here, since the list has not been received from another PNC, the process proceeds to step S011, and it is determined whether or not a change request has been received from the slave station (step not received (step S002)).

  Each list is examined again (step S105), and it is determined to which change request is issued (step S106). First, the number of patterns used by the piconet adjacent to each piconet is compared (step S301). Here, the piconet 3 and the piconet 4 are adjacent to the piconet 1 and use the patterns 2 and 3, respectively. Similarly, the piconet 5 adjacent to the piconet 2 uses the pattern 2. Here, since there are fewer on the piconet 2 side, the change destination is PNC2.

  If there is no difference in the number of patterns, the number of networks adjacent to each piconet is compared and the smaller one is selected (step S302). If there is no difference here, the identification number of the master station of each piconet is seen, and the smaller one is selected here based on a predetermined rule (step S303).

  Subsequently, the pattern to be changed is determined. First, since the pattern 2 is already used in the piconet 5 adjacent to the change destination piconet 2, it cannot be changed to the pattern 2 (step S401). Next, the pattern used by the piconet adjacent to the piconet (in this case, the piconet 1) that does not issue a change request is one pattern 2 and one pattern 3. However, since pattern 2 cannot be used, pattern 3 is the most frequently used piconet adjacent to piconet 1. Therefore, the pattern 3 is changed (step S402).

  Here, if there is no difference in the number, it is checked whether there is a difference in the pattern numbers used by the piconet adjacent to the network other than the change destination (step S403). If there is a difference, select the younger one. If there is no network adjacent to the network other than the change destination, a person with a lower number of usable communication control information is selected (step S404).

  Since the change destination and the communication control information are determined, a change request to the pattern 3 is issued to the PNC 2 that is the change destination (step S110). The PNC 2 that has received the change request (step S011) changes the pattern used in the piconet 2 to the pattern 3 (step S012). As a result, the pattern used by the piconet 2 and the information of the adjacent piconet have changed, and the list is updated (step S013). The usage patterns are changed from pattern 1 to pattern 3, and PNC1, DEV1-3, and pattern 1 are newly added as adjacent piconets.

  The updated list is transmitted (step S014), and the adjacent PNC list is also updated. The updated list issued by PNC2 relays DEV1-3 and DEV2 (step S111), and passes to PNC1 and PNC5 (step S009). The PNC that has received the updated list updates its own list with reference to the updated list (step S010).

  Then, the newly entered DEV1-3 starts communication with the PNC1 (step S112, FIG. 12).

  Further, consider a case where piconets exist apart as shown in FIG. In this case, there are two piconets in the space, and PNC 6 communicates with DEV 6 and pattern 1, and PNC 7 communicates with DEV 7-1 and pattern 1. In this state, each piconet can communicate without causing interference.

  Here, as shown in FIG. 14, considering the case where DEV7-2 has newly entered, DEV7-2 overlaps the overlapping range of communication ranges of DEV6 and PNC7, and the communication range of DEV7-2 and PNC6 overlaps. DEV6 will enter the part. Here, since the piconet 6 and the piconet 7 perform communication using the same hopping pattern 1, the DEV 6 may receive interference from the DEV 7-2, and communication may not be performed. Similarly, even if DEV 7-2 tries to start communication with PNC 7, there is a possibility that communication cannot be performed due to interference from DEV 6 (FIG. 15). Therefore, also in this case, it is necessary to change the pattern in order to reduce interference.

  The PNC periodically transmits a list (step S001). In the piconet 6 that is already communicating, as shown in FIG. 16, the DEV 6 receives the list issued by the PNC 6 (step S201). Is further transmitted to the surroundings (step S202). As a result, the newly entered DEV 7-2 receives two types of lists: a list from the PNC 7 and a list from the PNC 6. In addition, the PNC 6 and the PNC 7 do not receive a list from another PNC (step S002).

  The change destination and communication control information are determined according to the flowchart below. Although omitted here, the change destination is PNC 6 and the communication control information is pattern 2.

  The DEV 7-2 needs to issue a change request toward the PNC 6, but cannot directly transmit the DEV 7-2, and passes the change request by relaying the DEV 6. The DEV 6 that has received the change request from the DEV 7-2 (step S206) transmits it to the PNC 6 that is its own master station (step S207). The PNC 6 that has received the change request changes the pattern in accordance with the request and updates the list. Then, the updated list is transmitted to the surroundings.

  The DEV 6 that has received the updated list (step S208) further relays the DEV 7-2 (step S209), and is sent to the PNC 7. The PNC 7 that has received the updated list (step S009) refers to it and updates its own list (step S010).

  Then, the newly entered DEV 7-2 starts communication with the PNC 7 (FIG. 17).

  Further, consider a case where three piconets overlap at the same time as shown in FIG. In this case, there are three piconets in the space, and PNC 8 communicates with DEV 8-1 and pattern 1, PNC 9 communicates with DEV 9 and pattern 1, and PNC 10 communicates with DEV 10 and pattern 1. In this state, each piconet can communicate without causing interference.

  Here, as shown in FIG. 19, it is assumed that DEV8-2 has newly entered a portion where the communication ranges of PNC8, PNC9 and PNC10 overlap. Since PNC8, PNC9, and PNC10 perform communication using the same pattern 1, respectively, there is a possibility that interference may occur and communication cannot be performed as it is. Therefore, the pattern is changed to reduce interference.

  Since the PNC periodically transmits the list (step S001), the DEV 8-2 receives the PNC8 list, the PNC9 list, and the PNC10 list (step S101). Here, since there are a plurality of lists (step S102), each list is examined (step S103) to check which pattern is used in each PNC. Here, since all three patterns 1 are used (step S104), the pattern is changed. In addition, PNC8, PNC9, and PNC10 do not receive a list from another PNC (step S002).

  The change destination and communication control information are determined according to the flowchart below. Although omitted here, the change destinations are PNC8 and PNC9, and the communication control information is pattern 2 and pattern 3. Here, since there are three PNCs using the same pattern, it is necessary to issue change requests to the two PNCs.

  Thereafter, the pattern is changed and the list is updated in the same manner as in the first and second embodiments. Then, the newly entered DEV 8-2 starts communication with the PNC 8 (FIG. 20).

  Further, a case is considered where the piconet 11 and the piconet 12 as shown in FIG. 21 have overlapping communication ranges between the master stations as shown in FIG. In this case, PNC 11 and DEV 11 are communicating with pattern 1 first, and PNC 12 and DEV 12 are communicating with pattern 1. In this state, each piconet can communicate without causing interference.

  Here, it is assumed that the PNC 12 enters the communication range of the PNC 11 and the PNC 11 enters the communication range of the PNC 12 as shown in FIG. At this time, since the communication range of the PNC 11 and the communication range of the PNC 12 overlap, if the same frequency hopping pattern is used, interference may occur and communication may not be performed. Therefore, the pattern is changed to reduce interference.

  Since the PNC periodically sends a list (step S001), the PNC 11 has its own list and the list received from the PNC 12 (step S002), and the PNC 12 has its own list and the list received from the PNC 11 (step S002). Each will own. Here, since there are a plurality of lists, each list is examined (step S003), and it is checked which pattern is used in each PNC. Here, since both use pattern 1 (step S004), the pattern is changed.

  Each list is checked again (step S005), and which parent station is changed is checked (step S006). Although omitted here, the change destination is PNC11.

  Here, paying attention to the PNC 11, since the change destination is itself (step S007), the pattern to be changed is determined (step S008). Here, pattern 2 is obtained. When the change pattern is determined, the pattern is changed (step S012), and the list is updated (step S013). When the list is updated, the updated list is transmitted to the surroundings (step S014), and communication is started (step S015).

  On the other hand, paying attention to the PNC 12, since the change destination is not itself (step S013), the process waits as it is. When the updated list is received (step S009), the list is updated (step S010), and communication is started (step S015).

  As described above, in the embodiment, the example in which the multiband OFDM method is adopted has been described. However, the present invention is not limited to this, and the CDMA method may be used as a communication method. Moreover, it is not restricted to these two types.

  In this case, for example, if spreading code patterns 1 to 4 as shown in FIG. 25 are used as the communication control information, the same effect as the multiband OFDM scheme can be obtained.

  The present invention is not limited to IEEE 802.15.3 MAC, and may be applied between different MACs.

  Furthermore, in the present invention, the wireless communication devices (slave station 100 and master station 200) that constitute the wireless communication system can operate by being connected to a personal computer, AV equipment, and other information equipment.

  From the above, according to the wireless communication device of the present application, even if interference occurs when a new communication device enters a part where communication ranges of a plurality of networks overlap, communication control information is allocated well. Therefore, interference can be reduced.

  Further, according to the present invention, even if there are few types of communication control information, it is possible to prevent useless allocation of communication control information and to mix many networks.

  In addition, since the wireless version of USB 2.0 is considered as a wireless version of a PC (personal computer) peripheral device, the present invention can be applied to, for example, a printer, a scanner, a USB-connected hard disk, and the like. In addition, since wireless transmission of AV equipment in the home can be considered, it can be applied to a digital TV, a digital recorder, a tuner, and the like.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims. That is, embodiments obtained by combining technical means appropriately changed within the scope of the claims are also included in the technical scope of the present invention.

  Note that each unit and each processing step of the wireless communication apparatus (slave station 100 and master station 200) of the above embodiment are programs stored in a storage unit such as a ROM (Read Only Memory) or a RAM by a calculation unit such as a CPU. This is realized by controlling the input means such as the keyboard, the output means such as the display, or the communication means such as the interface circuit. Therefore, the computer having these means can realize various functions and various processes of the wireless communication apparatus of the present embodiment simply by reading the recording medium storing the program and executing the program. In addition, by recording the program on a removable recording medium, the various functions and various processes described above can be realized on an arbitrary computer.

  As this recording medium, a program medium such as a memory (not shown) such as a ROM may be used for processing by the microcomputer, or a program reader is provided as an external storage device (not shown). It may be a program medium that can be read by inserting a recording medium therein.

  In any case, the stored program is preferably configured to be accessed and executed by the microprocessor. Furthermore, it is preferable that the program is read out, and the read program is downloaded to a program storage area of the microcomputer and the program is executed. It is assumed that this download program is stored in advance in the main unit.

  The program medium is a recording medium configured to be separable from the main body, such as a tape system such as a magnetic tape or a cassette tape, a magnetic disk such as a flexible disk or a hard disk, or a disk such as a CD / MO / MD / DVD. Fixed disk, IC card (including memory card), etc., or semiconductor ROM such as mask ROM, EPROM (Erasable Programmable Read Only Memory), EEPROM (Electrically Erasable Programmable Read Only Memory), flash ROM, etc. In particular, there are recording media that carry programs.

  In addition, if the system configuration is capable of connecting to a communication network including the Internet, the recording medium is preferably a recording medium that fluidly carries the program so as to download the program from the communication network.

  Further, when the program is downloaded from the communication network as described above, it is preferable that the download program is stored in the main device in advance or installed from another recording medium.

  In an environment where there are a plurality of networks formed by a wireless communication device serving as a master station and a plurality of wireless communication devices serving as slave stations, wireless LAN in a home, wireless LAN in an office, and wireless in a home It can also be applied to uses such as communication of AV equipment.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates an embodiment of the present invention, in which (a) is a block diagram illustrating a main part configuration of a slave station, and (b) is a block diagram illustrating a main part configuration of a master station. It is a figure which shows an example of the list information memorize | stored in the main | base station shown in FIG.1 (b). It is a figure which shows the state which several piconet adjoined in the state with interference. It is a figure which shows the state which several piconet adjoined in the state without interference. It is a flowchart which shows the flow of operation | movement of the main | base station shown in FIG.1 (b). It is a flowchart which shows the flow of operation | movement of the subunit | mobile_unit shown to Fig.1 (a). It is a flowchart which shows the flow of operation | movement of the subunit | mobile_unit shown to Fig.1 (a). It is a flowchart which shows the flow of a change destination determination process in a master station and a slave station. It is a flowchart which shows the flow of a process of communication control information determination in a master station and a slave station. It is a figure which shows the state in which the some piconet exists adjacently for demonstrating one Example of this invention. FIG. 11 is a diagram illustrating a state where a child station is newly introduced in an area where the communication ranges of the piconet illustrated in FIG. 10 overlap. It is a figure which shows the result of having achieved interference reduction by applying this invention in the state shown in FIG. It is a figure which shows the state in which two piconets exist adjacently for demonstrating the other Example of this invention. FIG. 14 is a diagram illustrating a state where a slave station is newly introduced into one communication range of the piconet illustrated in FIG. 13. FIG. 15 is a diagram showing the start of processing for reducing interference by applying the present invention in the state shown in FIG. 14. FIG. 15 is a diagram showing a processing operation for reducing interference by applying the present invention in the state shown in FIG. 14. It is a figure which shows the completion of the process for aiming at interference reduction by applying this invention in the state shown in FIG. It is a figure which shows the state in which the three piconets exist adjacently for demonstrating the further another Example of this invention. FIG. 19 is a diagram illustrating a state in which a child station is newly introduced in an area where the communication ranges of the piconet illustrated in FIG. 18 overlap. It is a figure which shows the result of having achieved interference reduction by applying this invention in the state shown in FIG. It is a figure which shows the state in which a part of two piconet exists in order to demonstrate the further another Example of this invention. FIG. 22 is a diagram illustrating a state in which a slave station is newly introduced in an area where the communication ranges of the piconet illustrated in FIG. 21 overlap. It is a figure which shows the result of having achieved interference reduction by applying this invention in the state shown in FIG. It is a figure which shows an example of the frequency hopping pattern used with a multiband OFDM system. It is a figure which shows an example of the spreading code used with a CDMA system.

Explanation of symbols

100 Slave station 101 Change destination determination unit (change destination determination means)
102 Communication control information determination unit (communication control information determination means)
103 Information storage unit 104 Control unit 105 Communication control information comparison unit 106 Transmission unit 107 Reception unit 108 Antenna 200 Master station 201 Change destination determination unit (change destination determination means)
202 Communication control information determination unit (communication control information determination means)
203 List storage unit 204 Information storage unit 205 Control unit 206 List processing unit 207 Transmission unit 208 Communication control information control unit (communication control information changing means)
209 Receiver 210 Antenna

Claims (17)

When performing multiple access, communication methods for separating signals are classified in advance and set as a plurality of different communication control information, and communication is performed according to one of the communication control information specified by the master station. A wireless communication device serving as a slave station in a communication system to perform,
When communication control information received from multiple master stations matches, the type of communication control information used in other networks that overlap each parent station and the communication range, and other networks that overlap each parent station and communication range And a change destination determination means for determining a change destination parent station of the communication control information based on either the number of the network and the identification number of the master station of each network,
The identification number of the communication control information managed by the master station of the network whose communication range overlaps with the master station other than the master station of the change destination determined by the change destination determining means, and other networks whose communication range overlaps with each master station And a communication control information determining means for determining communication control information to be changed based on any of the types of communication control information. When performing multiple access, communication methods for separating signals are classified in advance and set as a plurality of different communication control information, and communication is performed according to one of the communication control information specified by the master station. A wireless communication device serving as a master station in a communication system to perform,
If the communication control information managed by the own wireless communication device matches the communication control information received from another master station, the communication control information used in other networks where the communication range overlaps with each master station Change destination determination that determines the change master station of the communication control information based on the type of the network, the number of other networks that overlap the communication range of each master station, and the identification number of the master station of each network Means,
The identification number of the communication control information managed by the master station of the network whose communication range overlaps with the master station other than the master station of the change destination determined by the change destination determining means, and other networks whose communication range overlaps with each master station And a communication control information determining means for determining communication control information to be changed based on any of the types of communication control information.   The wireless communication apparatus according to claim 2, further comprising communication control information changing means for changing communication control information currently managed to communication control information determined by the communication control information determining means. A list information storage means for storing the type of the communication control information, the number of other networks overlapping the communication range of each master station, and the identification number of the master station of each network as rewritable information;
The list information rewriting means for rewriting the list information based on the changed communication control information when the communication control information is changed by the communication control changing means is provided. Wireless communication device. The change destination determination means includes
The wireless communication apparatus according to claim 1 or 2, wherein a parent station having the smallest type of communication control information used in another network having a communication range overlapping each parent station is determined as a change destination. The change destination determination means includes
The wireless communication apparatus according to claim 1 or 2, wherein a parent station having the smallest number of other networks overlapping with each parent station is determined as a change destination. The change destination determination means includes
The radio communication apparatus according to claim 1 or 2, wherein a master station selected by an identification number of a master station compared according to a predetermined rule is determined as a change destination among the master stations. The communication control information determining means includes
The wireless communication apparatus according to claim 1 or 2, wherein communication control information that is not used in another network whose communication range overlaps with a change-destination master station is determined as communication control information to be changed. The communication control information determining means includes
The communication control information that is used most frequently among the types of communication control information used in other networks whose communication range overlaps with a master station that is not the change destination is determined as communication control information to be changed. Item 3. The wireless communication device according to Item 1 or 2. The communication control information determining means includes
The communication control information to be changed is determined by the identification number of the communication control information compared according to a predetermined rule among the communication control information used in other networks whose communication range overlaps with the master station that is not the change destination The wireless communication apparatus according to claim 1 or 2.   The wireless communication apparatus according to claim 1, wherein the communication control information is a frequency hopping pattern used in a frequency hopping method.   The wireless communication apparatus according to claim 1 or 2, wherein the communication control information is a spreading code pattern used in a CDMA (Code Division Multiple Access) system. When performing multiple access, communication methods for separating signals are classified in advance and set as a plurality of different communication control information, and communication is performed according to one of the communication control information specified by the master station. In the communication system to perform,
A wireless communication system comprising: the wireless communication device according to claim 1 as a slave station; and the wireless communication device according to claim 2 as a parent station. The slave station includes a change request unit that requests the master station to change the communication control information when the communication control information determination unit determines the communication control information to be changed.
14. The wireless communication system according to claim 13, wherein the master station includes communication control information changing means for changing communication control information based on a request from the change request means of the slave station. On the computer,
When communication control information received from multiple master stations matches, the type of communication control information used in other networks that overlap each parent station and the communication range, and other networks that overlap each parent station and communication range Determining the master station to which the communication control information is to be changed based on either the number of the master station and the identification number of the master station of each network,
The identification number of the communication control information managed by the master station of the network whose communication range overlaps with the master station other than the change-destination master station determined by the above procedure, and the communication control of other networks whose communication range overlaps with each master station A program for executing a procedure for determining communication control information to be changed based on any of the types of information. On the computer,
When the communication control information managed by the wireless communication device that is the master station of the network matches the communication control information received from the master station of the other network, the other stations that overlap the communication range with each master station Based on the type of communication control information being used, the number of other networks that overlap the communication range of each master station, and the identification number of the master station of each network, The procedure for determining the station,
The identification number of the communication control information managed by the master station of the network whose communication range overlaps with the master station other than the change-destination master station determined by the above procedure, and the communication control of other networks whose communication range overlaps with each master station A program for executing a procedure for determining communication control information to be changed based on any of the types of information.   The computer-readable recording medium which recorded the program in any one of Claim 15 or 16.

Images