JP4809547B2 - Wireless communication method and repeater thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a wireless communication method and a repeater thereof.
[0002]
[Prior art]
In recent years, Bluetooth has been developed as a technology for connecting a terminal to other terminals and peripheral devices.
[0003]
Bluetooth is a technology for connecting each terminal, peripheral device, and the like using a short-range radio, and has attracted a great deal of attention as a technology for connecting each device wirelessly without using a cable.
[0004]
Conventionally, there are technologies that use infrared rays to connect terminals and peripheral devices wirelessly. However, this method is used when the infrared rays themselves are highly directional and there is something that shields them. There was a problem with the degree of freedom and ease of connection.
[0005]
On the other hand, the Bluetooth technology uses a short-range radio, has no directivity, and is strong against shielding, so that convenience is greatly improved.
[0006]
Furthermore, according to the Bluetooth standard, it is possible to easily connect between terminals and peripheral devices without being operated by a user, without selecting a time and place.
[0007]
In this Bluetooth standard, radio in the 2.4 GHz frequency band is used, and it is possible to communicate with devices within a range of up to about 100 m at a maximum speed of 1 Mbps.
[0008]
However, in the communication technology using Bluetooth, since the number of slave terminals that can be connected to one master terminal is limited to 7 in one piconet, communication is performed using 8 or more slave terminals. There is a problem that is impossible.
[0009]
However, when a plurality of piconets overlap, slave terminals belonging to the overlapped area can be connected to the plurality of piconets by time division multiplex connection.
[0010]
Therefore, a slave terminal belonging to the overlapped area uses a master terminal in one area as a slave terminal, thereby forming a scatter net in which a plurality of piconets are gathered.
[0011]
In this scatter net, communication is possible between a plurality of piconets, so that terminals can communicate with each other via a master terminal of each piconet or a slave terminal in an area where a plurality of piconets overlap.
[0012]
[Problems to be solved by the invention]
However, in order for the master terminals of each piconet to communicate with each other, one side must be switched to a slave, and slave terminals belonging to overlapping areas in a scatternet can communicate with each other in a plurality of piconets. Since the connection destination piconet must be switched and one terminal cannot connect to multiple piconets at the same time, it is difficult to transfer data between the piconets in real time, resulting in a relatively large delay in data communication. There is a problem that arises.
[0013]
Here, as a technique for performing communication between a plurality of networks, there is a wireless communication method disclosed in Japanese Patent Application Laid-Open No. 11-308240. However, this conventional technique is applied to overlapping areas in a plurality of communication groups. Since the nodes to which the nodes belong are configured to function as bridges that connect the respective groups, it is possible to transfer data between a plurality of communication groups via a bridge. There is no description about the case where it is applied to a communication method having the relationship of
[0014]
As described above, in the current communication method using Bluetooth, it is impossible for nine or more terminals to communicate in real time.
[0015]
Accordingly, the present invention has been made in view of such problems, and an object of the present invention is to provide a radio communication method and a repeater thereof capable of performing data communication with a small delay between a plurality of piconets. .
[0016]
[Means for Solving the Problems]
This wireless communication method
A wireless communication method in which a master terminal and a slave terminal transmit and receive data via a repeater included in a plurality of piconets,
The repeater is
Two Bluetooth module
Have
Above Two Among the Bluetooth modules, one Bluetooth module connected to the piconet where the master terminal exists is a slave module, and the other Bluetooth module is a master module.
The piconet including the master terminal is the highest hierarchy,
A piconet other than the piconet set as the highest hierarchy is set as a hierarchy lower than the highest hierarchy.
[0017]
This , Double Data communication can be performed with a small delay between a plurality of piconets.
[0018]
That is , Double Since a Bluetooth repeater that relays and transfers data between a number of piconets is used, data requiring real time can be transmitted to a destination terminal with a small delay time. In addition, a Bluetooth network in which eight or more slave terminals are virtually connected to one master terminal can be formed. As a result, convenience is improved particularly when handwritten data is broadcast in real time to a large number of terminals in a conference or lecture.
[0020]
This , Double Data communication can be performed with a small delay between a plurality of piconets. In addition, a terminal included in a piconet other than the piconet including the master terminal is set as a slave of the Bluetooth repeater, and this Bluetooth repeater is set as a slave of the master terminal, so that substantially all terminals are slave terminals of the master terminal. It becomes possible.
[0022]
This , Double Since all the terminals connected to the Bluetooth network composed of several piconets execute the session protocol using the session terminal identifiers of other terminals, the flexibility of network construction can be improved.
[0024]
This , Example For example, if a chairperson terminal operating as a master is out of the network for some reason, the chairperson after that is transferred to a terminal connected to the same piconet or a terminal connected to another piconet, and the terminal of the transfer destination Since this becomes the master, it is possible to prevent a decrease in the data transmission efficiency of the Bluetooth network in such a case.
[0026]
This , B By using a plurality of luetooth repeaters and providing a hierarchical structure between the Bluetooth repeaters, even when terminals exist in a wide range, these terminals can be connected to the Bluetooth network.
[0027]
This repeater
A relay that relays data between a master terminal and a slave terminal,
Connect to a piconet Two Bluetooth module
Have
Above Two Among the Bluetooth modules, one Bluetooth module connected to the piconet where the master terminal exists is a slave module, and the other Bluetooth module is a master module.
The piconet including the master terminal is the highest hierarchy,
A piconet other than the piconet set as the highest hierarchy is set as a hierarchy lower than the highest hierarchy.
[0028]
This , Double Data communication can be performed with a small delay between a plurality of piconets.
[0029]
That is , Double Since a Bluetooth repeater that relays and transfers data between a number of piconets is used, data requiring real time can be transmitted to a destination terminal with a small delay time. In addition, a Bluetooth network in which eight or more slave terminals are virtually connected to one master terminal can be formed. As a result, convenience is improved particularly when handwritten data is broadcast in real time to a large number of terminals in a conference or lecture.
[0031]
This , Double Data communication can be performed with a small delay between a plurality of piconets. In addition, a terminal included in a piconet other than the piconet including the master terminal is set as a slave of the Bluetooth repeater, and this Bluetooth repeater is set as a slave of the master terminal, so that substantially all terminals are slave terminals of the master terminal. It becomes possible.
[0033]
This , B By using a plurality of luetooth repeaters and providing a hierarchical structure between the Bluetooth repeaters, even when terminals exist in a wide range, these terminals can be connected to the Bluetooth network.
[0035]
This , B Multiple antennas used by luetooth repeaters have directivity, and their directivity directions are different from each other to reduce radio wave interference and are more distant with the same transmission power than omnidirectional Wireless communication with a terminal at a position is possible.
[0036]
DETAILED DESCRIPTION OF THE INVENTION
[Features of the present invention]
First, the features of the present invention will be described first.
[0037]
A first object of the present invention is to provide a Bluetooth repeater with a plurality of communication modules and operate the communication modules simultaneously to transfer data between a plurality of piconets in real time.
[0038]
Since a Bluetooth repeater requires one communication module for the piconet to be connected, for example, when using Bluetooth to transfer data between two piconets in real time, Bluetooth located between the two piconets The repeater requires two communication modules.
[0039]
At the same time, it is a specific object to connect a plurality of piconets to each other so that eight or more slave terminals can be virtually connected to one master terminal.
[0040]
Accordingly, the present invention provides a terminal other than the Bluetooth relay connected to each piconet in a Bluetooth network including a plurality of piconets including a plurality of Bluetooth modules and each Bluetooth module connected to a separate piconet. The master terminal has a configuration for performing data communication with a terminal connected to a plurality of piconets via the Bluetooth repeater.
[0041]
Second, 8 or more slave terminals are virtually connected to one master terminal using a Bluetooth repeater specialized in the function of relaying and transferring data between a plurality of piconets. The specific purpose is to form a Bluetooth network.
[0042]
Therefore, in the present invention, in addition to the above configuration, the Bluetooth repeater is connected as a slave when using a Bluetooth module connected to the piconet where the master terminal exists, and connected to other piconets. When communication is performed using a Bluetooth module, it has a configuration that operates as a master.
[0043]
Third, the Bluetooth repeater transmits the session terminal identifiers of all terminals connected to the piconet that operates as a master to the piconet master terminal that operates as a slave, and receives this. The master terminal can manage the session terminal identifiers of all terminals connected to the Bluetooth network consisting of a plurality of piconets together with the session terminal identifiers of all terminals connected to the piconet to which the own terminal is connected. It has a specific purpose. This is defined in the Bluetooth standard as a maximum of 7 slave terminals that can be connected to one master terminal, and in accordance with the standard, the master terminal can communicate with the master terminal during the inquiry procedure. The Bluetooth device address (BD_ADDR) of the slave terminal can be obtained. However, when data communication such as electronic conference communication is executed by connecting multiple piconets, the Bluetooth relay device at the connection point of multiple piconets is used for the application. This is because the address (BD_ADDR) is not necessarily necessary information, and it is more convenient for the application to use a terminal identifier used in the session layer of the data communication protocol as a terminal identifier than BD_ADDR. At the same time, a specific object is to enable all terminals connected to a Bluetooth network composed of a plurality of piconets to execute a session protocol using the terminal identifiers for other terminals.
[0044]
Therefore, in addition to the above-described configuration, the present invention transmits the terminal identifier for session connection of all terminals connected to the piconet operating as a master to the master terminal of the piconet operating as a slave. The received master terminal is configured to execute a session protocol using all terminals connected to a Bluetooth network composed of a plurality of piconets and the terminal identifier for the session connection.
[0045]
Fourth, the antenna connected to each Bluetooth module of the Bluetooth repeater should have directivity, and the directivity directions should be different from each other to reduce radio wave interference and compared to the non-directional case. A specific object is to enable wireless communication with a terminal located more distantly at the same transmission power.
[0046]
Therefore, in the present invention, in addition to the above configuration, at least one antenna among the plurality of antennas connected to each Bluetooth module has directivity.
[0047]
Fifth, if a chairman terminal operating as a master is disconnected from the network for any reason, the chairman thereafter is transferred to a terminal connected to the same piconet or a terminal connected to another piconet, and the transfer is performed. The specific purpose is to make the previous terminal a master. This is because with Bluetooth, data cannot be transmitted directly from a slave terminal to another slave terminal, and always passes through the master terminal. This is because when the terminal becomes the master, the data transmitted from the chairman terminal has good transmission efficiency in the network.
[0048]
Therefore, in addition to the above-described configuration, the present invention has a configuration in which a master terminal exchanges a master with a terminal connected to the same piconet or a terminal connected to another piconet.
[0049]
Sixth, by using a plurality of Bluetooth repeaters and providing a hierarchical structure between the Bluetooth repeaters, even if terminals exist in a wide range, they can be connected to the Bluetooth network. The specific purpose is to connect.
[0050]
Therefore, in addition to the above-described configuration, the present invention has a configuration in which a plurality of the above-described Bluetooth repeaters are used to form a Bluetooth network having a hierarchical structure.
[0051]
Hereinafter, the preferred embodiment of the present invention will be described with examples. In the following embodiments, a case where an electronic conference is executed on a Bluetooth network including a portable display pad mounted with Bluetooth and a Bluetooth repeater having a plurality of Bluetooth modules will be described as an example.
[0052]
[First embodiment]
・ Bluetooth network configuration
As a first embodiment of the present invention, FIG. 1 shows an example of a Bluetooth network in which a Bluetooth repeater has two Bluetooth modules and each Bluetooth module is connected to a separate piconet.
[0053]
Referring to FIG. 1, the Bluetooth network includes a Bluetooth repeater 1, a chairman terminal 2 as a master, and 13 slave terminals (3 to 15). In FIG. 1, M represents a master and S represents a slave.
[0054]
The master of the piconet 16 is the chairman terminal 2, and the BT (Bluetooth) module 67 of the Bluetooth repeater 1 is connected as a slave. On the other hand, the master of the piconet 17 is the BT (Bluetooth) module 69 of the Bluetooth repeater 1.
[0055]
-Terminal (portable display pad) configuration (appearance)
Next, the external appearance of the portable display pad as the master terminal 2 and the slave terminals (3 to 15) is shown in FIG. In FIG. 2, 20 is a portable display pad as a master terminal and a slave terminal (common to the master terminal 2 and slave terminals (3 to 15)), 43 is an LCD, 45 is a touch panel attached to the LCD 43 in an overlapping manner, 21 Is a touch pen used when a touch input operation is performed on the touch panel 45.
[0056]
-Terminal (portable display pad) configuration (block)
Next, the hardware configuration of the portable display pad 20 is shown in FIG. In FIG. 3, a portable display pad 20 includes a CPU 30, a main memory 31, a UART 32, a Bluetooth module 33, an antenna 34, a clock 35, a bus controller 36, a ROM 37, a PCI bridge 38, a cache memory 39, a hard disk 40, an HD controller 41, The LCD display controller 42, LCD 43, touch panel controller 44, touch panel 45, RTC 46, battery 47, DC-DC converter 48, CPU bus 49, PCI bus 50, X bus (internal bus) 51, and the like.
[0057]
In this configuration, the CPU 30 executes and processes a control processing program, an OS (Operating System), and various application programs stored in a ROM (Read Only Memory) 37.
[0058]
The main memory 31 is composed of a DRAM (Dynamic Random Access Memory) and is used in a work area of the CPU 30 or the like.
[0059]
A UART (Universal Asynchronous Receiver Transmitter) 32 is an interface that transmits and receives serial data between the CPU 30 and the Bluetooth module 33, and includes a FIFO (First In, First Out), a shift register, and the like.
[0060]
The Bluetooth module 33 includes an RF unit and a baseband unit, and executes wireless communication conforming to the Bluetooth standard. Details of this will be described later.
[0061]
The clock 35 is composed of a crystal oscillator and a frequency dividing circuit, and generates a clock for controlling the operation timing of the CPU 30 and the bus controller 36.
[0062]
The bus controller 36 controls data transfer between the CPU bus 49 and the X bus 51.
[0063]
The ROM 37 is pre-programmed with programs for starting up the system when the power is turned on and controlling various devices.
[0064]
A PCI (Peripheral Component Interconnect) bridge 38 uses the cache memory 39 to perform data transfer between the PCI bus 50 and the CPU 30.
[0065]
The cache memory 39 is composed of a DRAM and is used by the PCI bridge 38.
[0066]
The hard disk 40 stores system software, various application programs, a lot of user data, and the like.
[0067]
An HD (hard disk) controller 41 is an interface with the hard disk 40 and performs high-speed data transfer with the hard disk 40. This interface is IDE (Integrated Device Electronics).
[0068]
The LCD display controller 42 performs D / A (Digital / Analog) conversion of characters and graphic data and performs control for displaying these data on the LCD 43.
[0069]
The touch panel controller 44 detects a portion where the pen tip of the touch pen 21 contacts on the touch panel 45 and takes in the position information.
[0070]
The touch panel 45 is overlapped and in close contact with the LCD 43.
[0071]
An RTC (Real Time Clock) 46 is a date clock, and is backed up by a dedicated battery (not shown).
[0072]
The battery 47 is, for example, a nickel metal hydride battery, a lithium battery, or the like, and current is supplied into the portable display pad 20 via the DC-DC converter 48.
[0073]
・ Bluetooth repeater configuration (block)
Next, the hardware configuration of the Bluetooth repeater 1 is shown in FIG. In FIG. 4, a part surrounded by a dotted line is the main body of the Bluetooth repeater 1 and includes a CPU 60, a clock 61, a main memory 62, a ROM 63, RS-232C64, RS-232C65, a CPU bus 66 and the like.
[0074]
The CPU 60 executes the operation of this embodiment according to the control processing program stored in the ROM 63.
[0075]
The clock 61 is composed of a crystal oscillator and a frequency dividing circuit, and generates a clock for controlling the operation timing of the CPU 60 and the CPU bus 66.
[0076]
The main memory 62 is composed of DRAM and is used in the work area of the CPU 60 and the like.
[0077]
A program for controlling the operation of the Bluetooth repeater 1 is written in the ROM 63 in advance.
[0078]
The RS-232C64 and the RS-232C65 are configured by a UART, a clock generation circuit, and an RS-232C connector, and transmit and receive data according to the RS-232C standard with the Bluetooth module 67 and the Bluetooth module 69, respectively.
[0079]
The Bluetooth module 67 and the Bluetooth module 69 have a configuration in which an RS-232C connector is added to the Bluetooth module 33 of the portable display pad 20 shown in FIG. 3, and an antenna 68 and an antenna 70 are connected thereto.
[0080]
The RS-232C 64 and the Bluetooth module 67, and the RS-232C 65 and the Bluetooth module 69 are connected by an RS-232C cable, respectively.
[0081]
・ Protocol configuration of terminal (portable display pad)
Next, the protocol configuration of the portable display pad 20 is shown in FIG. In FIG. 5, SIEA (Still Image Exchange and Annotation) 80, MBFT (Multipoint Binary File Transfer) 81, NC (Node Controller) 82, GCC (Generic Conference Control) 83, SDE (Service Discovery Entity) 84, LMCE (Link Manager) Control Entity) 85 is an application, and there is also a user application (not shown).
[0082]
The SIEA 80 is a whiteboard application that adds to a whiteboard area shared by all terminals and performs various drawing operations. An operation conforming to 126 is executed.
[0083]
The MBFT 81 is an application for transferring files such as conference materials. The operation | movement based on 127 is performed.
[0084]
NC82 and GCC83 are conference control applications in which terminals connected to the Bluetooth network execute a conference according to the control of the chairman, and manage a list of terminal information such as capabilities and attributes of each terminal. For example, ITU-T Recommendation T. The operation conforming to 124 is executed.
[0085]
The SDE 84 is an application that confirms services that can be used with a partner terminal and examines the characteristics of those services.
[0086]
The LMCE 85 is an application for passing a command to the link manager 94 when the master and the slave are exchanged, for example, other than the RFCOMM and SDP protocols.
[0087]
An MCS (Multipoint Communication Service) 86 executes a session layer protocol between multiple points. An operation conforming to 125 is executed.
[0088]
X.224 (87) is an ITU-T recommendation X.X. It conforms to 224 class 0 and executes a transport layer protocol for performing flow control of data transfer and the like.
[0089]
T.A. 70NULL88 is an ITU-T recommendation T.70. A network layer protocol compliant with 70 NULL is executed.
[0090]
A PPP (Point to Point Protocol) 89 executes a data link layer protocol on a serial line.
[0091]
RFCOMM (RF COMMunication) 90 is a protocol for emulating a serial port on an L2CAP (Logical Link Control and Adaptation Protocol) protocol.
[0092]
An SDP (Service Discovery Protocol) 91 provides a method of checking services that can be used with a partner terminal and checking characteristics of those services.
[0093]
The L2CAP 92 executes upper protocol multiplexing, data packet (L2CAP packet) division and assembly, and the like.
[0094]
An HCI (Host Controller Interface) 93 is an interface between the host (CPU 30) and the Bluetooth module 33 in the portable display pad 20, and includes an HCI API (Application Program Interface), a host (CPU 30), the Bluetooth module 33, and the like. And a hardware driver of the Bluetooth module 33.
[0095]
The link manager 94 executes LMP (Link Manager Protocol) for performing link setting and link control during master / slave exchange operation.
[0096]
The baseband 95 executes establishment of a physical link, transmission / reception of various packets, and the like.
[0097]
The physical layer 96 performs signal modulation by GFSK (Gaussian Frequency Shift Keying), spread spectrum communication by frequency hopping, and the like.
[0098]
Here, the use frequency band of Bluetooth is 2471 to 2497 MHz (Japan), the number of hopping channels is 23 (1 MHz interval), and the hopping speed is 1600 hops / second. Further, the channel is divided into 625 μsec time slots, the master terminal starts packet transmission in even-numbered time slots, and the slave terminal starts packet transmission in odd-numbered time slots.
[0099]
In the above protocol configuration, the hardware driver (in the HCI 93) of the UART driver and the Bluetooth module 33, the link manager 94, the baseband 95, and the physical layer 96 are mounted on the Bluetooth module 33. Otherwise, the CPU 30 The software modules (tasks) executed in the above are stored in advance in the hard disk 40 as execution programs.
[0100]
-Protocol configuration of Bluetooth repeater
Next, the protocol configuration of the Bluetooth repeater 1 is shown in FIG. As shown in FIG. 6, the protocol configuration of the Bluetooth repeater 1 has no SIEA 80, MBFT 81, and GCC 83 from the protocol configuration of the portable display pad 20 shown in FIG. 5, but instead establishes an MCS connection, joins an MCS channel, etc. The protocol configuration of the portable display pad 20 is the same as that of the portable display pad 20 except that there is an MCSCE (Multipoint Communication Service Control Entity) 97 that controls the MCS.
[0101]
However, in the Bluetooth repeater 1, the HCI 93 is an interface between the host (CPU 60) and the Bluetooth module 67 and the Bluetooth module 69, and between the HCI API, the host (CPU 60), the Bluetooth module 67, and the Bluetooth module 69. It consists of hardware drivers of RS-232C, Bluetooth module 67, and Bluetooth module 69 that function as a transport layer.
[0102]
In the protocol configuration of FIG. 6, the RS-232C driver and the Bluetooth module 67, the hardware driver of the Bluetooth module 69 (in the HCI 93), the link manager 94, the baseband 95, and the physical layer 96 are the Bluetooth module 67 and the Bluetooth module. The other modules are software modules (tasks) that are executed by the CPU 60 and are stored in advance in the ROM 63 as execution programs.
[0103]
・ Bluetooth communication sequence until Bluetooth network formation
Next, a Bluetooth communication sequence until a Bluetooth network (piconet) is formed will be described with reference to the piconet 16 shown in FIG.
[0104]
..Establishing communication connection with Bluetooth repeater
In this communication sequence, the master terminal (chairperson terminal) 2 first recognizes all slave terminals that can communicate with the master terminal 2 by the inquiry procedure. That is, the master terminal 2 repeatedly transmits an ID packet, and the slave terminal that receives the ID packet transmits an FHS packet including the Bluetooth device address (BD_ADDR), the system clock of the terminal itself, and the like. Thereby, the master terminal 2 recognizes the number of slave terminals from the number of received FHS packets (the number of BD_ADDR).
[0105]
In the piconet 16 shown in FIG. 1, the chairman terminal 2 recognizes seven slave terminals (one is a Bluetooth module of the Bluetooth repeater 1). The recognized number of slave terminals and the received device address BD_ADDR are stored in the main memory 31.
[0106]
Next, the master terminal 2 first searches for the Bluetooth repeater 1 from the recognized slave terminals, and first connects to the Bluetooth repeater 1 if any. That is, the terminal having the device address BD_ADDR previously stored in the main memory 31 and the link manager and link (link layer) connection are sequentially established and the service discovery sequence is performed to check whether each is a Bluetooth repeater. To do. The Bluetooth repeater 1 has a Bluetooth relay service (a uniquely defined service that is not defined in the Bluetooth standard).
[0107]
In this operation, when the other party has a Bluetooth relay service, the master terminal 2 establishes a communication connection to the partner terminal (Bluetooth repeater 1) to the application. If the other party does not have the Bluetooth relay service, the master terminal 2 disconnects the link layer connection. The details of the communication connection establishment procedure are the same as the operation sequence between the portable display pads described below.
[0108]
..Establishing communication connections with multiple slave terminals
Next, the master terminal 2 sequentially establishes communication connections with the six slave terminals. The communication connection establishment procedure will be described.
[0109]
The master terminal 2 transmits an ID packet including a synchronization word derived from LAP (Lower Address Part) which is a lower address part of the device address BD_ADDR received from the slave terminal during the inquiry procedure. On the other hand, when the slave terminal (any of 3 to 8, omitted below) receives an ID packet including a synchronization word derived from the device address BD_ADDR of the own terminal, it responds with an ID packet.
[0110]
Next, the master terminal 2 transmits an FHS packet in which 1 is set in the active member address (AM_ADDR) that is the identification number of the slave terminal. When receiving this, the slave terminal responds with an ID packet. At this time, the slave terminal switches to the system clock of the master terminal included in the FHS packet.
[0111]
Next, the master terminal 2 transmits a POLL packet, and the slave terminal responds with a NULL packet to establish a baseband layer connection.
[0112]
Subsequently, the master terminal 2 and the slave terminal move to a link establishment sequence between link managers (link layer).
[0113]
First, the master terminal 2 transmits an LMP_host_connection_req PDU (Protocol Data Unit), and the slave terminal responds with an LMP_accepted PDU.
[0114]
Next, the master terminal transmits an LMP_features_req PDU, and the slave terminal responds with an LMP_features_res PDU to exchange information about the functions of the own terminal.
[0115]
Next, the master terminal 2 transmits an LMP_setup_complete PDU, and the slave terminal responds with the LMP_setup_complete PDU to establish a link-manager (link layer) connection.
[0116]
Subsequently, the master terminal 2 executes a service discovery sequence.
[0117]
When the application of the master terminal 2 issues a service discovery request to the SDP task, the SDP task issues a connection connection request (L2CA_ConnectReq event) to the L2CAP task. When the L2CAP task receives this request, it transmits a Connection Request packet.
[0118]
When the L2CAP task of the slave terminal receives this packet, it passes the L2CA_ConnectInd message to the SDP task and responds with a Connection Response packet to the master terminal 2 to establish the SDP connection.
[0119]
Subsequently, the SDP task issues a configuration request (L2CA_ConfigReq event) to the L2CAP task. Upon receipt of this request, the L2CAP task transmits a Configuration Request packet including configuration parameters such as quality of service (QoS).
[0120]
When the L2CAP task of the slave terminal receives this packet, it passes an L2CA_ConfigInd message to the SDP task and responds to the master terminal 2 with a Configuration Response packet including configuration parameters.
[0121]
Next, the SDP task of the master terminal 2 sends an SDP_ServiceSearchRequest PDU including a UUID (service unique identifier) indicating that it is an electronic conference service (a uniquely defined service not defined in the Bluetooth standard) in the ServiceSearchPattern parameter. The SDP task of the slave terminal responds with an SDP_ServiceSearchResponse PDU.
[0122]
Then, when the application of the master terminal confirms that the slave terminal connected now is an electronic conference terminal, it issues a connection request to the MCS task. This connection request is sequentially issued to a lower layer, and a PPP connection, an X.224 connection, and an MCS connection are sequentially established. And the connection between each entity of GCC, SIEA, and MBFT which is a meeting application is established, and it will be in the state which can perform communication between each entity.
[0123]
As described above, the communication sequence until the drawing data and the file can be transferred using the MCS connection between the master terminal 2 and one slave terminal (for example, the slave terminal 3) has been described. Executes the same communication sequence for the other five terminals (slave terminal 4 to slave terminal 8) that can be connected to the piconet, and the master terminal 2, the slave terminal 3 to the slave terminal 8, and the Bluetooth repeater 1 ( A piconet consisting of a Bluetooth module 67) is formed.
[0124]
..Operation of Bluetooth repeater 1
Subsequently, in parallel with the operation as the slave, the Bluetooth repeater 1 starts the operation as the master using the Bluetooth module 69. That is, the Bluetooth repeater 1 sequentially establishes communication connections with the slave terminals 9 to 15 by the same operation as described above, and forms a piconet with the Bluetooth repeater 1 (using the Bluetooth module 69) as a master.
[0125]
Thus, a Bluetooth network composed of two piconets with the Bluetooth repeater 1 as a relay point is formed.
[0126]
Next, an MCS connection between all terminals connected to a Bluetooth network composed of two piconets and a connection between entities such as GCC as a conference application will be described.
[0127]
First, the MCS connection will be described. The MCS 86 shown in FIGS. 5 and 6 is called an MCS provider. Further, a Bluetooth network composed of two piconets as a network between MCS providers is called an MCS domain.
[0128]
The MCS domain in the network configuration of FIG. 1 has a hierarchical structure as shown in FIG. The master terminal 2 serving as the chairperson is the top MCS provider and is located in the highest layer. The slave terminals 3 to 8 and the Bluetooth repeater 1 are located in the intermediate layer, and the slave terminals 9 to 15 are located in the lowest layer.
[0129]
Each terminal attaches to the MCS domain after the MCS connection is established. By this attachment, each terminal acquires an MCS user ID that is a terminal identifier in the MCS domain.
[0130]
Next, each terminal joins the MCS channel. The MCS channel is an address in the MCS domain, and all terminals that have joined the same channel receive data sent to that channel. Here, when the slave terminal 9 transmits data to a channel to which all terminals are subscribed, the data is first transferred to the Bluetooth relay 1, and the Bluetooth relay 1 transmits this data to the slave terminals 10 to 15. To the master terminal 2 which is the top MCS provider. Then, the master terminal 2 transfers this data to the slave terminals 3 to 8.
[0131]
In this way, data can be transmitted to all terminals by all terminals joining the same channel. The MCS user ID, which is a terminal identifier in the MCS domain, is also used as an MCS channel number, and is used as an MCS channel number when transmitting data to an individual destination.
[0132]
Next, the GCC and node controller (NC) that are conference control applications will be described. The GCC 83 shown in FIGS. 5 and 6 is called a GCC provider. A GCC provider of a terminal that is a top MCS provider is called a top GCC provider. When each GCC provider participates in the conference, it transmits a list of conference applications such as SIEA and MBFT and terminal information (conference node list) such as an MCS user ID which is a terminal identifier in the MCS domain to all other GCC providers. To do. This broadcast transmission is realized by transmitting data to the MCS channel to which all terminals are subscribed. These terminal information is received by each terminal and managed by NC83. The GCC also controls the assignment of chairmanship, etc., and the top GCC provider has the chairmanship at the start of the conference. The node controller (NC 83) issues various primitives to the GCC 83 according to a request from the user, and manages an application list, a conference node list, and the like of its own terminal and all other terminals.
[0133]
Since the Bluetooth repeater 1 does not have GCC, terminal information such as an MCS user ID, which is a terminal identifier in the MCS domain, is not transmitted to other terminals, and the chair terminal and the Bluetooth repeater 1 are terminals participating in the conference. Not considered.
[0134]
In this manner, the conference material file, handwritten drawing data, and the like are transmitted from each terminal to all terminals or individual terminals under the chairperson control, and the electronic conference is executed.
[0135]
・ Overview of operation
FIG. 8 shows the schematic operation flow in the chairman terminal 2 (portable display pad 20) as the master, and FIG. 9 shows the schematic operation flow in the Bluetooth repeater 1.
[0136]
..Outline operation flow in master terminal
Referring to FIG. 8, in this operation, the master terminal 2 obtains the device address BD_ADDR of each slave terminal in the communicable range by the inquiry means and the number of BD_ADDRs (the number M of slave terminals), and stores them. (Step S101).
[0137]
Next, the master terminal 2 substitutes 1 for n (step S102). This is a part of the processing for executing the subsequent processing for all the slave terminals.
[0138]
As described above, first, assuming that n = 1, the master terminal 2 establishes a connection between the slave terminal having the n (= 1) th BD_ADDR and the link manager, thereby establishing a link (step S103). Further, the master terminal 2 executes a service discovery sequence (step S104). At this time, the master terminal 2 determines whether or not this slave terminal is the Bluetooth repeater 1 (step S105).
[0139]
As a result of the determination in step S105, when the nth slave terminal is not the Bluetooth repeater 1 (No in step S105), the master terminal 2 disconnects the link with the slave terminal (step S108).
[0140]
Further, the master terminal 2 determines whether or not the current value of n is equal to the number M of slave terminals in the communication range (step S109). If they are equal (Yes in step S109), step S111 is performed. If they are not equal (No in step S109), the value of n is incremented by 1 (step S110), and the process returns to step S103.
[0141]
On the other hand, if the result of determination in step S105 is that the nth slave terminal is the Bluetooth repeater 1 (Yes in step S105), the master terminal 2 connects each layer to the slave terminal (up to the application). Communication communication) is sequentially established (step S106), 1 is subtracted from the number M of slave terminals (step S107), and the process proceeds to step S111.
[0142]
As described above, the operations so far are repeatedly executed until all slave terminals in the communicable range are executed or until the connection with the Bluetooth repeater 1 is established.
[0143]
Although not shown in FIG. 8, when there are a plurality of Bluetooth repeaters in a range where communication with the master terminal 2 is possible, the closest Bluetooth repeater is connected. A description of the method by which the master terminal 2 determines the nearest Bluetooth relay device from among a plurality of Bluetooth relay devices is omitted.
[0144]
Next, in step S111, the master terminal 2 first substitutes 1 for the value of k (step S111). This is because, similarly to the above, the subsequent processing is executed for all slave terminals except for the Bluetooth repeater 1 in the communicable range.
[0145]
Next, the master terminal 2 establishes a communication connection between the slave terminal having the kth device address and the link manager (step S112), and further executes a service discovery sequence (step S113).
[0146]
Thereafter, the master terminal 2 determines whether or not the partner slave terminal is a terminal that participates in a conference managed by the master terminal 2 (step S114), and if it is a terminal that participates (Yes in step S114), A communication connection (communication connection up to the application) of each layer with the slave terminal is sequentially established (step S115), and the process proceeds to step S118. If the slave terminal is not a participating slave terminal (No in step S114), the master terminal 2 determines whether or not the current value of k is equal to the number M of slave terminals excluding the Bluetooth relay device 1 in the communicable range. If it is determined (step S116) and they are equal (Yes in step S116), the process proceeds to step S121. If they are not equal (No in step S116), the master terminal 2 increments the value of k by 1 (step 117), and proceeds to step S112.
[0147]
In step S118, it is determined whether or not the number of slave terminals that have established communication connections with the master terminal 2 at present is equal to the limit number (seven) in the piconet (step S118). (No in S118), it is determined whether or not the current value of k is equal to the number M of slave terminals excluding the Bluetooth relay device 1 in the communicable range (step S119), and if equal (Yes in step S119). The process proceeds to step S121. If they are not equal (No in step S119), the master terminal 2 increments the value of k by 1 (step 120), and proceeds to step S112.
[0148]
In step S121, the master terminal 2 performs broadcast transmission of data to be transmitted to all slave terminals and data transmission to an individual destination using an MCS user ID which is a terminal identifier in the MCS domain. An authorized operation is also executed (step S121).
[0149]
..Outline operation flow in Bluetooth repeater
Moreover, the schematic operation | movement flow of the Bluetooth repeater 1 in a present Example is demonstrated using FIG.
[0150]
Referring to FIG. 9, in this operation, the Bluetooth repeater 1 first operates as a slave to establish a communication connection in response to a request from the master terminal (chairman terminal) 2 (step S201). This operation corresponds to the master terminal 2 in the operation shown in FIG.
[0151]
Next, the Bluetooth repeater 1 operates as a master, thereby obtaining the number M of slave terminals in the communicable range and the device address BD_ADDR of each slave terminal by the inquiry procedure and storing them ( Step S202). This operation is the same as that of the master terminal 2 in FIG.
[0152]
Next, the Bluetooth repeater 1 first substitutes 1 for the value of n (step S203). This is because the subsequent processing is executed for all slave terminals within the communicable range.
[0153]
After substituting 1 for n in this way, the Bluetooth repeater 1 establishes a communication connection between the slave terminal having the nth device address and the link manager (step S204), and further executes a service discovery sequence ( Step S205).
[0154]
After that, the Bluetooth repeater 1 determines whether or not the partner slave terminal is a terminal that participates in the conference managed by the master terminal 2 (step S206), and if it is a terminal that participates (Yes in step S206). Then, the communication connection (communication connection up to the application) of each layer with the slave terminal is sequentially established (step S207), and the process proceeds to step S210. Further, when the slave terminal is not a participating slave terminal (No in step S206), the Bluetooth relay device 1 determines whether or not the current value of n is equal to the number M of slave terminals in the communicable range (step S208). If equal (Yes in step S208), the process proceeds to step S213. If they are not equal (No in step S208), the Bluetooth repeater 1 increments the value of n by 1 (step 209), and proceeds to step S204.
[0155]
In step S210, it is determined whether or not the number of slave terminals that have established communication connections with the Bluetooth repeater 1 at present is equal to the limit number (seven) in the piconet (step S210). In Step S210 No), it is determined whether or not the current value of n is equal to the number M of slave terminals in the communicable range (Step S211). If they are equal (Yes in Step S211), the process proceeds to Step S213. . If they are not equal (No in step S211), the Bluetooth relay device 1 increments the value of n by 1 (step S212), and proceeds to step S204.
[0156]
In step S213, the MCS provider of the Bluetooth repeater 1 executes data transfer to the slave terminal (step S213).
[0157]
As described above, the present embodiment has been described for the case where the Bluetooth repeater 1 has two Bluetooth modules. However, the present embodiment can also be applied to the case where the Bluetooth repeater 1 has three or more Bluetooth modules. For example, when the Bluetooth repeater 1 has three Bluetooth modules and each Bluetooth module is connected to a separate piconet, one Bluetooth module is operated as a slave of the master terminal 2 which is the chair terminal, and the other two Each Bluetooth module operates as a master. As a result, an MCS domain is formed between terminals connected to the three piconets.
[0158]
[Second Embodiment]
Next, a second embodiment of the present invention will be described in detail with reference to the drawings.
[0159]
In this embodiment, a directional antenna is used as an antenna to be connected to each Bluetooth module of the Bluetooth repeater 1 shown in the first embodiment, and two Bluetooth modules are built in the Bluetooth repeater 1 main body. Is. The hardware configuration of the Bluetooth repeater 1 in this case is shown in FIG.
[0160]
In FIG. 10, the CPU 60, the clock 61, the main memory 62, the ROM 63, and the CPU bus 66 are the same as the respective components of the Bluetooth repeater 1 of the first embodiment shown in FIG.
[0161]
Further, in FIG. 10, UART 71 and UART 72 are the same as UART 32 shown in FIG. 3, and Bluetooth module 73 and Bluetooth module 75 are the same as Bluetooth module 33 shown in FIG.
[0162]
However, in FIG. 10, the antenna 74 and the antenna 76 are directional antennas, and as this directional antenna, for example, a planar antenna having a corrugated structure as shown in FIG. 11 is used. This planar antenna can change the directivity range of the E plane (denoted as E-plane in the figure), which is a radio wave radiation plane, by changing the dimension of the corrugation groove depth CL (Corrugation Length). This E plane is a plane including the direction in which the electric field vibrates (polarization direction) as shown in FIG. FIG. 11 shows a case where the plane of the planar antenna is in the vertical direction. The antenna 74 and the antenna 76 shown in FIG. 10 are mounted so that the E plane is in the horizontal direction, that is, the plane of the planar antenna is in the horizontal direction.
[0163]
Further, the Bluetooth module 73 and the Bluetooth module 75 are installed so that the directivity directions of the antenna 74 and the antenna 76 are different from each other. FIG. 12 shows an example of the transmission radio wave range of each antenna when two Bluetooth modules are used.
[0164]
Referring to FIG. 12, by arranging the antenna 74 and the antenna 76 as described above, in this embodiment, it is possible to prevent the areas covered by the antennas from overlapping more than necessary. .
[0165]
Instead of incorporating two Bluetooth modules in the body of the Bluetooth repeater 1, the length of the RS-232C cable is shortened in the configuration shown in FIG. You may make it the structure installed so that it may mutually differ.
[0166]
Moreover, even when the Bluetooth repeater 1 has three or more Bluetooth modules to which directional antennas are connected, the antennas may be mounted so that the directivity directions of the antennas are different from each other.
[0167]
[Third embodiment]
Next, in the Bluetooth network composed of the two piconets shown in the first embodiment, a case will be described in which the master terminal 2 serving as the chairperson transfers the chairperson right to another terminal during the communication conference and leaves the Bluetooth network.
[0168]
In the Bluetooth network shown in FIG. 1, a whiteboard application (using SIEA 80), a file transfer application (using MBFT 81), and a conference control application (using GCC 83) are being executed between all terminals. .
[0169]
Here, when the master terminal 2 transfers the chairmanship to the slave terminal 10 connected to the piconet 17, the NC 82 sends the GCC-CONDUCTOR- including the node ID (same as the MCS user ID) of the slave terminal 10 to the GCC 83. Pass the GIVE-request primitive.
[0170]
The GCC 83 sets these parameters in the data area, and passes the MCS-SEND-DATA-request primitive in which the node ID of the slave terminal 10 is set to the channel ID to the MCS 86.
[0171]
In the MCS 86, when data is transmitted to the designated channel ID, this data is transmitted to the slave terminal 10.
[0172]
When the slave terminal 10 receives this data, the NC 82 returns a GCC-CONDUCTOR-GIVE-response to the master terminal 2 and notifies all terminals that the terminal will become the new chairperson. GCC-CONDUCTOR-ASSIGN- Send.
[0173]
In this way, the chair terminal in the MCS domain is switched from the master terminal 2 to the slave terminal 10. Thereafter, the master terminal 2 disconnects the GCC, MCS, X.224, and PPP layers.
[0174]
Next, the master terminal 2 performs an exchange operation between the Bluetooth repeater 1 and the master / slave.
[0175]
First, the link manager 94 transmits an LMP_switch_req PDU and receives an LMP_accepted PDU from the Bluetooth repeater 1. Then, the master / slave exchange operation is executed in the baseband 95. That is, the master terminal 2 and the Bluetooth repeater 1 first invert the TX timing and the RX timing, and at this point, the Bluetooth repeater 1 becomes the master.
[0176]
And the terminal 2 which became a slave performs the sequence for operate | moving synchronizing with the clock of the Bluetooth repeater 1. FIG.
[0177]
Then, the Bluetooth repeater 1 includes the new AM_ADDR in the FHS packet and transmits it to the terminal 2.
[0178]
Thereafter, the Bluetooth repeater 1 sequentially performs an operation sequence for the slave side to adjust to the new master clock and transmission of a new AM_ADDR for each slave terminal with respect to the other terminals (terminal 3 to terminal 8) connected to the piconet 16. Execute.
[0179]
In this way, the master of the piconet 16 is switched from the terminal 2 to the Bluetooth relay 1.
[0180]
Thereafter, the terminal 2 transmits an LMP_detach PDU at the link manager 94 to detach from the Bluetooth network.
[0181]
Subsequently, the Bluetooth repeater 1 performs a master / slave exchange operation with the slave terminal 10 connected to the piconet 17. That is, the link manager 94 of the Bluetooth repeater 1 transmits an LMP_switch_req PDU and receives an LMP_accepted PDU from the slave terminal 10.
[0182]
The Bluetooth repeater 1 and the slave terminal 10 invert the TX timing and the RX timing, and the terminal 10 becomes the master at this time.
[0183]
Then, the Bluetooth repeater 1 that has become a slave executes a sequence for operating in synchronization with the clock of the terminal 10.
[0184]
Then, the terminal 10 includes the new AM_ADDR in the FHS packet and transmits it to the Bluetooth repeater 1.
[0185]
Thereafter, the terminal 10 sends an operation sequence for the slave side to adjust to the new master clock and transmission of a new AM_ADDR for each slave terminal to the other terminals (terminal 9, terminal 11 to terminal 15) connected to the piconet 17 Run sequentially.
[0186]
In this way, the master of the piconet 17 is switched from the Bluetooth repeater 1 to the terminal 10. The terminal 10 operates as a master terminal of the Bluetooth network, as a top MCS provider in the MCS domain, and as a chairman of an electronic conference.
[0187]
FIG. 13 shows the schematic operation flow in the terminal 2, FIG. 14 shows the schematic operation flow in the Bluetooth repeater 1, and FIG. 15 shows the schematic operation flow in the terminal 10.
[0188]
-Outline operation flow in terminal 2
First, with reference to FIG. 13, an outline of an operation until the terminal 2 switches from the master to the slave and leaves the Bluetooth network will be described.
[0189]
Referring to FIG. 13, in this operation, the terminal 2 first assigns the chairmanship to the slave terminal 10 (step S301).
[0190]
Next, the terminal 2 disconnects the communication connection of each layer of GCC, MCS, X.224, and PPP (step S302), and then executes an exchange operation between the Bluetooth repeater 1 and the master / slave (step S303). .
[0191]
By operating in this way, since the terminal 2 functions as a slave, even if the terminal 2 leaves the Bluetooth network, the function of the Bluetooth network itself is not impaired. Therefore, thereafter, the terminal 2 leaves the Bluetooth network (step S304).
[0192]
・ Outline operation flow in Bluetooth repeater
Moreover, with reference to FIG. 14, the operation | movement when the Bluetooth repeater 1 switches a master from the terminal 2 to the terminal 10 is demonstrated.
[0193]
Referring to FIG. 14, in this operation, the Bluetooth repeater 1 first disconnects the communication connection of each layer of X.224 and PPP established with the terminal 2 (step S401).
[0194]
Next, the Bluetooth repeater 1 performs an exchange operation from the master to the slave on the terminal 2 (step S402).
[0195]
Thereafter, the Bluetooth repeater 1 performs an exchange operation from the slave to the master on the terminal 10 (step S403).
[0196]
As a result, the master for the Bluetooth repeater 1 is switched from the terminal 2 to the terminal 10.
[0197]
-Outline operation flow in terminal 10
Further, an outline of an operation when the terminal 10 is switched from the slave to the master will be described with reference to FIG.
[0198]
Referring to FIG. 15, in this operation, when the terminal 10 first receives the chairmanship from the terminal 2, the terminal 10 becomes the chairman terminal of the main conference (step S501).
[0199]
Next, the terminal 10 executes an operation of switching from the slave to the master with the Bluetooth repeater 1, and becomes the master (step S502).
[0200]
Thereafter, the terminal 10 becomes a top MCS provider in the MCS domain (step S503).
[0201]
As a result, the terminal 10 can be operated from the slave to the master.
[0202]
[Fourth embodiment]
A case will be described below where there are a plurality of Bluetooth repeaters shown in FIG. 4 and each Bluetooth repeater is connected by a Bluetooth network.
[0203]
In the present embodiment, a Bluetooth network when there are three Bluetooth repeaters is shown as an example in FIG.
[0204]
Referring to FIG. 16, the Bluetooth network according to the present embodiment includes a Bluetooth repeater 1, a Bluetooth repeater 100, a Bluetooth repeater 110, a chairman terminal 2 serving as a master, 25 slave terminals (3-13, 121-127, 131-137). In FIG. 16, M means a master and S means a slave.
[0205]
The network configuration in FIG. 16 has a hierarchical structure as shown in FIG. In this hierarchical structure, the master terminal 2 serving as the chairman is the highest layer, the Bluetooth repeater 1 and the slave terminals 3 to 8 are the second layer, the Bluetooth repeater 100, the Bluetooth repeater 110, and the slave terminals 9 to the slave terminals. 13 is the third layer, and the slave terminal 121 to the slave terminal 127 and the slave terminal 131 to the slave terminal 137 are located in the fourth layer.
[0206]
FIG. 17 is also a hierarchical structure of MCS providers in the MCS domain. That is, the master terminal 2 that is the chairman is the top MCS provider and is located in the highest layer. Therefore, all terminals connected to this MCS domain operate under chairperson control, and meeting material files, handwritten drawing data, etc. are transmitted from each terminal to all terminals or to individual terminals. A meeting is performed.
[0207]
[Other Examples]
In each of the above-described embodiments, as a protocol on the RFCOMM 90, PPP, T.P. Although 70 NULL and X.224 are used, other protocols such as PPP and TCP / IP may be used.
[0208]
The present invention can also be applied to applications other than electronic conferences.
[0209]
However, each of the above-described embodiments is merely one form of carrying out the present invention, and the present invention can be implemented with various modifications without departing from the gist thereof.
[0210]
【The invention's effect】
As described above, according to the first aspect of the present invention, there is provided a wireless communication method in which a master terminal and a slave terminal transmit and receive data via a repeater included in a plurality of piconets, wherein the repeater is One of the plurality of Bluetooth modules is a slave and the other is a master so that data can be transmitted and received between a plurality of piconets, thereby enabling data communication with a small delay between a plurality of piconets Can be performed.
[0211]
In other words, according to the first aspect of the present invention, since a Bluetooth repeater that relays and transfers data between a plurality of piconets is used, data requiring real time can be transmitted to a destination terminal with a small delay time. Can do. In addition, a Bluetooth network in which eight or more slave terminals are virtually connected to one master terminal can be formed. As a result, convenience is improved particularly when handwritten data is broadcast in real time to a large number of terminals in a conference or lecture.
[0212]
Furthermore, according to the invention described in claim 2, among the plurality of Bluetooth modules, a Bluetooth module connected to a piconet in which a master terminal exists is set as a slave, and another Bluetooth module is set as a master. Data communication can be performed between a plurality of piconets with a small delay. In addition, a terminal included in a piconet other than the piconet including the master terminal is set as a slave of the Bluetooth repeater, and this Bluetooth repeater is set as a slave of the master terminal, so that substantially all terminals are slave terminals of the master terminal. It becomes possible.
[0213]
Furthermore, according to the invention of claim 3, the terminal identifier for the session connection of the terminal included in the piconet to which the Bluetooth module as the master belongs is transmitted to the master terminal, and the master terminal performs the session based on the terminal identifier. The flexibility of network construction because all terminals connected to the Bluetooth network consisting of multiple piconets execute the session protocol using the terminal identifier for the session of other terminals. Can be improved.
[0214]
Further, according to the invention described in claim 4, the master terminal exchanges the master with any one of the slave terminals included in the plurality of piconets, thereby operating as a master, for example. If the chairman's terminal is removed from the network for any reason, the subsequent chairperson is transferred to a terminal connected to the same piconet or a terminal connected to another piconet, and the destination terminal becomes the master. In this case, it is possible to prevent a decrease in the data transmission efficiency of the Bluetooth network.
[0215]
Furthermore, according to the invention described in claim 5, a plurality of piconets are arranged in a hierarchical structure in which the piconet including the master terminal is the highest hierarchy, and one Bluetooth module among the plurality of Bluetooth modules included in the repeater is Data is transmitted and received between multiple piconets by including them in piconets in higher layers than other Bluetooth modules, making the Bluetooth modules contained in higher-level piconets as slaves, and using other Bluetooth modules as masters. By using a plurality of Bluetooth repeaters and providing a hierarchical structure between each Bluetooth repeater, even if terminals exist in a wide range, the Bluetooth Can be connected to the network.
[0216]
According to the invention of claim 6, there are a plurality of Bluetooth modules connected to the piconet, one of the plurality of Bluetooth modules being a slave and the other being a master. It is possible to perform data communication between the piconets with a small delay.
[0217]
That is, according to the invention described in claim 6, since the Bluetooth repeater that relays and transfers data between a plurality of piconets is used, data requiring real time can be transmitted to the destination terminal with a small delay time. Can do. In addition, a Bluetooth network in which eight or more slave terminals are virtually connected to one master terminal can be formed. As a result, convenience is improved particularly when handwritten data is broadcast in real time to a large number of terminals in a conference or lecture.
[0218]
Furthermore, according to the invention described in claim 7, among the plurality of Bluetooth modules, the Bluetooth module connected to the piconet in which the master terminal exists is set as a slave, and the other Bluetooth module is set as a master. Data communication can be performed between a plurality of piconets with a small delay. In addition, a terminal included in a piconet other than the piconet including the master terminal is set as a slave of the Bluetooth repeater, and this Bluetooth repeater is set as a slave of the master terminal, so that substantially all terminals are slave terminals of the master terminal. It becomes possible.
[0219]
Furthermore, according to the invention described in claim 8, in a Bluetooth network composed of a plurality of piconets having a hierarchical structure in which the piconet including the master terminal is the highest hierarchy, it is included in a higher hierarchy than other Bluetooth modules. The feature is that the Bluetooth module is the slave and the other modules are the master. By using multiple Bluetooth repeaters, a hierarchical structure can be created between each Bluetooth repeater, thereby expanding the range of terminals. Even if they exist, they can be connected to the Bluetooth network.
[0220]
Furthermore, according to the invention described in claim 9, one or more of the plurality of antennas connected to each of the plurality of Bluetooth modules are directional antennas, whereby the Bluetooth repeater is Multiple antennas to be used have directivity, and their directivity directions are different from each other to reduce radio wave interference, and terminals that are farther away with the same transmission power than omnidirectional Wireless communication is possible.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a Bluetooth network according to a first embodiment of the present invention.
FIG. 2 is an external view of a portable display pad according to a first embodiment of the present invention.
FIG. 3 is a block diagram showing a hardware configuration of a portable display pad according to the first embodiment of the present invention.
FIG. 4 is a block diagram showing a hardware configuration of a Bluetooth repeater according to the first embodiment of the present invention.
FIG. 5 is a block diagram showing a protocol configuration of a portable display pad according to the first embodiment of the present invention.
FIG. 6 is a block diagram showing a protocol configuration of a Bluetooth repeater according to the first embodiment of the present invention.
FIG. 7 is a block diagram showing a hierarchical structure in an MCS domain according to the first embodiment of the present invention.
FIG. 8 is a flowchart showing a schematic operation of the chairman terminal (master terminal) 2 according to the first embodiment of the present invention.
FIG. 9 is a flowchart showing a schematic operation of the Bluetooth repeater 1 according to the first embodiment of the present invention.
FIG. 10 is a block diagram showing a hardware configuration of a Bluetooth repeater according to a second embodiment of the present invention.
FIG. 11 is a view for explaining a radio wave radiation surface of a planar antenna connected to a Bluetooth module of a Bluetooth repeater according to a second embodiment of the present invention;
FIG. 12 is a diagram illustrating an area covered by a Bluetooth module of a Bluetooth repeater according to a second embodiment of the present invention.
FIG. 13 is a flowchart showing a schematic operation of the terminal 2 according to the third embodiment of the present invention.
FIG. 14 is a flowchart showing a schematic operation of the Bluetooth repeater 1 according to the third embodiment of the present invention.
FIG. 15 is a flowchart showing a schematic operation of the terminal 10 according to the third embodiment of the present invention.
FIG. 16 is a block diagram showing a configuration of a Bluetooth network according to a fourth embodiment of the present invention.
FIG. 17 is a block diagram showing a hierarchical structure of a Bluetooth network according to a fourth embodiment of the present invention.
[Explanation of symbols]
1, 100, 110 Repeater (Bluetooth repeater)
2 terminals (master terminal, chairman terminal)
3-15, 121-127, 131-137 Slave terminal
16, 17, 201, 202, 203, 204 piconet
20 Portable display pad
21 Touch pen
30, 60 CPU
31, 62 Main memory
32 UART
33, 67, 69, 101, 102, 111, 112 Bluetooth module
34, 68, 70 Antenna
35, 61 clock
36 Bus controller
37, 63 ROM
38 PCI bridge
39 Cache memory
40 hard disk
41 HD controller
42 LCD display controller
43 LCD
44 Touch panel controller
45 Touch panel
46 RTC
47 battery
48 DC-DC converter
49, 66 CPU bus
50 PCI bus
51 X bus (internal bus)
64, 65 RS-232C
80 SIEA
81 MBFT
82 NC
83 GCC
84 SDE
85 LMCE
86 MCS
87 X.224
88 T.W. 70 NULL
89 PPP
90 RFCOMM
91 SDP
92 L2CAP
93 HCI
94 Link Manager
95 baseband
96 Physical layer (RF)
97 MCSCE

Claims (6)

A wireless communication method in which a master terminal and a slave terminal transmit and receive data via a repeater included in a plurality of piconets,
The repeater is
Have two Bluetooth modules,
Of the two Bluetooth modules, one Bluetooth module connected to the piconet in which the master terminal exists is a slave module, and the other Bluetooth module is a master module.
The piconet including the master terminal is the highest hierarchy,
A radio communication method, wherein a piconet other than the piconet set as the highest hierarchy is set as a hierarchy lower than the highest hierarchy. A wireless communication method in which a master terminal and a slave terminal transmit and receive data via a plurality of repeaters included in a plurality of piconets,
The repeater is
Have two Bluetooth modules,
Of the two Bluetooth modules, one Bluetooth module connected to the piconet in which the master terminal exists is a slave module, and the other Bluetooth module is a master module.
The plurality of piconets have a hierarchical structure in which a piconet including a master terminal is the highest hierarchy,
Among the plurality of Bluetooth modules included in the repeater, one Bluetooth module is included in a piconet in a higher hierarchy than the other Bluetooth modules, a Bluetooth module included in the piconet in the higher hierarchy is a slave module, and the other A wireless communication method comprising using a Bluetooth module as a master module.   3. The wireless communication method according to claim 1, wherein, when the master terminal and the slave terminal execute conference communication, the master terminal serves as a chairperson terminal. 4. The wireless communication method according to claim 1, wherein the master terminal exchanges a master with any one of slave terminals included in the plurality of piconets. A relay that relays data between a master terminal and a slave terminal,
It has two Bluetooth modules that connect to the piconet,
Of the two Bluetooth modules, one Bluetooth module connected to the piconet where the master terminal exists is a slave module, and the other Bluetooth module is a master module.
The piconet including the master terminal is the highest hierarchy,
A repeater characterized in that a piconet other than the piconet set as the highest hierarchy is set as a hierarchy lower than the highest hierarchy. In a Bluetooth network composed of a plurality of piconets having a hierarchical structure with the piconet including the master terminal as the highest hierarchy, between the repeater included in the piconet in the upper hierarchy and the slave terminals included in the piconet in the lower hierarchy And a relay that relays data,
The repeater is
Have two Bluetooth modules,
Of the two Bluetooth modules the repeater has a single Bluetooth module included in the piconet a higher level than the other Bluetooth modules, a Bluetooth module included in the piconet of the upper hierarchy and the slave module, the A repeater characterized by using another Bluetooth module as a master module.

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