JP2002368760A - Wireless communication method and repeater thereof - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a wireless communication method capable of performing data communication with a small delay between a plurality of piconets, and a repeater thereof. SOLUTION: A plurality of (two) Bluetooth repeaters 1 are provided.
It has etooth modules 67 and 69, and each Bluetooth module connects to a separate piconet. In the Bluetooth module connected to each piconet, the Bluetooth module 6 included in the same piconet as the master terminal 2
7 as a slave and the other Bluetooth module 69 as a master. The terminals 9 to 15 become slaves of the Bluetooth module 69, so that
, And data communication via a plurality of piconets becomes possible.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a radio communication method and a repeater thereof.

[0002]

2. Description of the Related Art In recent years, Bluetooth has been developed as a technique for connecting a terminal to another terminal or peripheral device.

[0003] This Bluetooth is a technology for connecting terminals, peripheral devices, and the like using a short-range radio, and has attracted much attention as a technology for connecting each device wirelessly without using a cable.

Conventionally, there has been a technology for connecting terminals and peripheral devices wirelessly with each other by using infrared rays. However, in this method, the infrared rays themselves have a strong directivity and there is a technique for shielding the infrared rays. Such that it cannot be used for
There were problems with the degree of freedom and ease of connection.

[0005] On the other hand, in the technology based on Bluetooth,
Since a short-range radio is used, there is no directivity, and it is strong against shielding, so that convenience is greatly improved.

[0006] Further, according to the Bluetooth standard, there is no need for user operation between terminals and peripheral devices.
The connection can be easily made at any time and place.

In the Bluetooth standard, radio in the 2.4 GHz frequency band is used, and it is possible to communicate with a device within a range of about 100 m at a maximum speed of 1 Mbps.

However, in the communication technology using Bluetooth, since the number of slave terminals that can be connected to one master terminal is limited to seven in one piconet, communication is performed using eight or more slave terminals. Is impossible to do.

[0009] However, when a plurality of piconets overlap, the slave terminals belonging to the overlapped area can be connected to the plurality of piconets by time division multiple access.

[0010] Therefore, a scatternet in which a plurality of piconets are gathered is formed by the slave terminals belonging to the overlapped area using the master terminal in one area as the slave terminal.

In this scatter net, since communication is possible between a plurality of piconets, it is possible that terminals communicate with each other via a master terminal of each piconet or a slave terminal in an area where a plurality of piconets overlap. Become.

[0012]

However, in order for the master terminals of each piconet to communicate with each other, one of them must be switched to the slave, and the slave terminals belonging to the overlapping area in the scatternet are In order to perform communication in a plurality of piconets, the connection destination piconet must be switched.
Since one terminal cannot be connected to a plurality of piconets at the same time, it is difficult to transfer data between the piconets in real time, and there is a problem that a relatively large delay occurs in data communication.

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. H11-308240. Are configured so that the nodes belonging to the designated area function as bridges connecting the respective groups.
Although it is possible to transfer data between a plurality of communication groups via a bridge, there is no description about a case where the present invention is applied to a communication method having a master / slave relationship such as Bluetooth.

As described above, at present, it is impossible for nine or more terminals to communicate in real time with a communication method using Bluetooth.

[0015] Accordingly, the present invention has been made in view of such a problem, and has as its object to provide a wireless communication method which enables data communication between a plurality of piconets with a small delay, and a repeater thereof. Aim.

[0016]

According to one aspect of the present invention, there is provided a wireless communication system in which a master terminal and a slave terminal transmit and receive data via a repeater included in a plurality of piconets. The method is characterized in that data transmission and reception are performed between a plurality of piconets by setting one of the plurality of Bluetooth modules included in the repeater as a slave and the other as a master.

Thus, according to the first aspect of the present invention, data communication can be performed between a plurality of piconets with a small delay.

That is, according to the first aspect of the present invention, the Bluetooth for relaying and transferring data between a plurality of piconets
Since a repeater 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, the convenience in the case where handwritten data is broadcast to many terminals in real time at a meeting or a lecture is improved.

Further, according to the present invention, a plurality of Blue
Among the tooth modules, a Bluetooth module connected to a piconet where a master terminal exists is set as a slave, and another Bluetooth module is set as a master.

According to the second aspect of the present invention, it is possible to perform data communication with a small delay between a plurality of piconets. Also, terminals included in a piconet other than the piconet including the master terminal are set as slaves of the Bluetooth repeater, and this Bluetooth repeater is set as a slave of the master terminal, so that virtually all terminals are slave terminals of the master terminal. It becomes possible.

Further, according to the invention of claim 3, the terminal identifier for the session connection of the terminal included in the piconet to which the master Bluetooth module belongs,
It is transmitted to the master terminal, and the master terminal executes a session protocol based on the terminal identifier.

According to the third aspect of the present invention, all terminals connected to the Bluetooth network composed of a plurality of piconets execute the session protocol using the session terminal identifier of the other terminal, so that network construction is performed. Flexibility can be improved.

Further, the invention according to claim 4 is characterized in that the master terminal exchanges the master with any one of the slave terminals included in the plurality of piconets.

Thus, in the invention according to claim 4, for example, if the chair terminal operating as the master is disconnected from the network for any reason, the subsequent chair is transferred to a terminal connected to the same piconet or another piconet. Since the terminal is transferred to the connected terminal and the transfer destination terminal becomes the master, it is possible to prevent a decrease in the data transmission efficiency of the Bluetooth network in such a case.

Further, in the invention according to claim 5, the plurality of piconets have a hierarchical structure in which the piconet including the master terminal is the highest hierarchy, and the plurality of Blue
Of the tooth modules, one Bluetooth module is included in a piconet of a higher layer than another Bluetooth module, and a Bluetooth module included in a piconet of a higher layer is included.
The oth module is used as a slave and another Bluetooth module is used as a master to transmit and receive data between a plurality of piconets.

According to the fifth aspect of the present invention, Bl
By using a plurality of uetooth repeaters and providing a hierarchical structure between the Bluetooth repeaters, even if the terminals exist in a wide range, the terminals can be connected to the Bluetooth network.

The invention according to claim 6 has a plurality of Bluetooth modules connected to a piconet and a plurality of Bluetooth modules.
One of the etooth modules is a slave, and the other is a master.

Thus, according to the present invention, it is possible to perform data communication with a small delay between a plurality of piconets.

That is, according to the sixth aspect of the present invention, the Bluetooth for relaying and transferring data between a plurality of piconets
Since a repeater 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, the convenience in the case where handwritten data is broadcast to many terminals in real time at a meeting or a lecture is improved.

Further, the invention according to claim 7 is characterized in that a plurality of Blue
Among the tooth modules, a Bluetooth module connected to a piconet where a master terminal exists is set as a slave, and another Bluetooth module is set as a master.

Thus, according to the present invention, it is possible to perform data communication with a small delay between a plurality of piconets. Also, terminals included in a piconet other than the piconet including the master terminal are set as slaves of the Bluetooth repeater, and this Bluetooth repeater is set as a slave of the master terminal, so that virtually all terminals are slave terminals of the master terminal. It becomes possible.

[0032] Further, the invention according to claim 8 includes, 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 layer, a layer higher than other Bluetooth modules is included. The Bluetooth module to be slaved,
It is characterized in that another module is used as a master.

Thus, in the invention according to claim 8, Bl
By using a plurality of uetooth repeaters and providing a hierarchical structure between the Bluetooth repeaters, even if the terminals exist in a wide range, the terminals can be connected to the Bluetooth network.

Further, according to the ninth aspect of the present invention, a plurality of Blue
One or more of a plurality of antennas connected to each tooth module are directional antennas.

Thus, according to the ninth aspect of the present invention, Bl
The uetooth repeater uses multiple antennas that have directivity, and their directivity directions are different from each other to reduce radio wave interference and increase the distance with the same transmission power compared to omnidirectional cases. Wireless communication with a terminal at a position becomes possible.

[0036]

DESCRIPTION OF THE PREFERRED EMBODIMENTS [Features of the Present Invention] First, the features of the present invention will be described first.

The first object of the present invention is to provide a Bluetooth repeater having a plurality of communication modules and operating these communication modules simultaneously to transfer data between a plurality of piconets in real time. I have.

Since one communication module is required for the piconet to be connected to the Bluetooth repeater, for example, when data is to be transferred between two piconets in real time using Bluetooth, between the two piconets, The located Bluetooth repeater requires two communication modules.

It is a specific object of the present invention to simultaneously connect a plurality of piconets to one another, thereby allowing one or more master terminals to be virtually connected to eight or more slave terminals. .

Accordingly, the present invention relates to a Bluetooth network comprising a plurality of piconets, each including a plurality of Bluetooth modules, each of which includes a Bluetooth transponder connected to a separate piconet. There is one master terminal among the other terminals, and the master terminal
It has a configuration for performing data communication with terminals connected to a plurality of piconets via a Bluetooth repeater.

Second, eight or more slave terminals are virtually connected to one master terminal by using a Bluetooth repeater specialized in a function of relaying and transferring data between a plurality of piconets. The purpose is to form a connected Bluetooth network.

Therefore, the present invention provides, in addition to the above configuration,
When the Bluetooth repeater communicates using the Bluetooth module connected to the piconet where the master terminal is located, it operates as a slave, and when it communicates using the Bluetooth module connected to another piconet, it operates as the master. It has a working configuration.

Third, the Bluetooth repeater transmits the session terminal identifiers of all the terminals connected to the piconet in which the own device operates as a master to the master terminal of the piconet in which the own device operates as a slave, The master terminal receiving this can manage the session terminal identifiers of all the terminals connected to the Bluetooth network composed of a plurality of piconets, together with the session terminal identifiers of all the terminals connected to the piconet to which the own terminal connects. The specific purpose is to do so. This is because the Bluetooth standard stipulates that up to seven slave terminals can be connected to one master terminal, and in accordance with the standard, all the master terminals may communicate with the master terminal during the inquiry procedure. Bluetooth device address of slave terminal (B
D_ADDR), but when connecting multiple piconets to perform data communication such as electronic conference communication, the application does not necessarily require the address of the Bluetooth repeater (BD_ADDR) at the multiple piconet connection points This is because it is more convenient for the application to use the terminal identifier used in the session layer of the data communication protocol as the terminal identifier than BD_ADDR. It is another specific object of the present invention to simultaneously enable all terminals connected to a Bluetooth network composed of a plurality of piconets to execute a session protocol using a session terminal identifier of another terminal.

Therefore, according to the present invention, in addition to the above configuration, the terminal identifiers for the session connections of all the terminals connected to the piconet operating as the master are transmitted to the master terminal of the piconet operating as the slave. The master terminal having received the terminal identifier executes a session protocol using all the terminals connected to the Bluetooth network composed of a plurality of piconets and the terminal identifier for the session connection.

Fourth, each Bluet of the Bluetooth repeater
Make the antenna connected to the ooth module have directivity,
Also, it is necessary to make the pointing directions different from each other to reduce radio wave interference and to enable wireless communication with a terminal located at a more distant position with the same transmission power as compared to the case of non-directionality. The purpose is.

Therefore, according to the present invention, in addition to the above-described configuration, at least one of the plurality of antennas connected to each Bluetooth module has directivity.

Fifth, if the chair terminal operating as the master leaves the network for any reason, the subsequent chair is transferred to a terminal connected to the same piconet or a terminal connected to another piconet. The specific purpose is to enable the transfer destination terminal to be the master. This is because in Bluetooth, data cannot be directly transmitted from a slave terminal to another slave terminal, but always passes through the master terminal. This is because, when the terminal becomes the master, data transmitted from the chair terminal has high transmission efficiency in the network.

Therefore, in addition to the above configuration, the present invention has a configuration in which the master terminal exchanges a master with a terminal connected to the same piconet or a terminal connected to another piconet.

Sixth, by using a plurality of Bluetooth transponders and providing a hierarchical structure between the respective Bluetooth transponders, even if the terminals are present in a wide range, these terminals can be used. The specific purpose is to connect to a Bluetooth network.

Therefore, 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, in addition to the above-described configuration.

Hereinafter, preferred embodiments of the present invention will be described with reference to examples. In each of the embodiments described below, a portable display pad equipped with Bluetooth and a plurality of
B consisting of Bluetooth repeater with etooth module
An example in which an electronic conference is performed on a luetooth network will be described.

[First Embodiment]-Bluetooth Network Configuration As a first embodiment of the present invention, 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 Is shown in FIG.

Referring to FIG. 1, the Bluetooth network includes a Bluetooth repeater 1, a chair terminal 2 as a master, and 13 slave terminals (3 to 15). In FIG. 1, M indicates a master and S indicates a slave.

The master of the piconet 16 is the chair 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 (Bluet
ooth) module 69.

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.
Reference numeral 20 denotes a portable display pad as the master terminal and the slave terminal (the master terminal 2 and the slave terminals (3 to 1)
5)), 43 is an LCD, 45 is a touch panel superimposed on and attached to the LCD 43, and 21 is a touch pen used when performing a touch input operation on the touch panel 45.

Terminal (Portable Display Pad) Configuration (Block) Next, the hardware configuration of the portable display pad 20 is shown in FIG.
Shown in In FIG. 3, the portable display pad 20 is a CPU 3
0, main memory 31, UART 32, Bluetooth module 33, antenna 34, clock 35, bus controller 36, ROM 37, PCI bridge 38, cache memory 39, hard disk 40, HD controller 41, LCD display controller 42, LCD 43, touch panel controller 44, Touch panel 45, RT
C46, battery 47, DC-DC converter 48, C
PU bus 49, PCI bus 50, X bus (internal bus) 5
1 and so on.

In this configuration, the CPU 30 includes a ROM
(Read Only Memory) 37 to execute and process the control processing program, OS (Operating System) and various application programs stored in the memory.

The main memory 31 includes a DRAM (Dynamic R).
andom Access Memory).
It is used in work areas.

UART (Universal Asynchronous Recei)
The ver transmitter 32 is an interface for transmitting and receiving 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 is composed of an RF unit and a baseband unit, and executes wireless communication conforming to the Bluetooth standard. The details will be described later.

The clock 35 is composed of a crystal oscillator and a frequency dividing circuit.
The clock for controlling the operation timing of is generated.

The bus controller 36 includes a CPU bus 49
And the X bus 51 to control data transfer.

In the ROM 37, a program for starting up the system at power-on and controlling various devices is written in advance.

A PCI (Peripheral Component Interconne)
ct) The bridge 38 performs data transfer between the PCI bus 50 and the CPU 30 using the cache memory 39.

The cache memory 39 is composed of a DRAM and is used by the PCI bridge 38.

The hard disk 40 stores system software, various application programs, a large number of user data, and the like.

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).

The LCD display controller 42 performs D / A (Digital / Analog) conversion of character and graphic data, and performs control for displaying these data on the LCD 43.

The touch panel controller 44 detects a portion of the touch panel 45 touched by the tip of the touch pen 21 and takes in the position information.

The touch panel 45 is superimposed on the LCD 43 and is in close contact therewith.

An RTC (Real Time Clock) 46 is a date clock, and is backed up by a dedicated battery (not shown).

The battery 47 is, for example, a nickel-metal hydride battery or a lithium battery, and a current is supplied to the inside of the portable display pad 20 via a DC-DC converter 48.

Next, the hardware configuration of the Bluetooth repeater 1 is shown in FIG. In FIG. 4, a portion surrounded by a dotted line is a main body of the Bluetooth repeater 1, and includes a CPU 60, a clock 61, a main memory 62, a ROM 63, an RS-232C64, and an RS-2.
32C65, a CPU bus 66 and the like.

The CPU 60 executes the operation of this embodiment according to the control processing program stored in the ROM 63.

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.

The main memory 62 is composed of a DRAM, and is used for a work area of the CPU 60 and the like.

A program for controlling the operation of the Bluetooth repeater 1 is written in the ROM 63 in advance.

RS-232C64 and RS-232C65
Is composed of a UART, a clock generation circuit, and an RS-232C connector, and transmits and receives data to and from the Bluetooth module 67 and the Bluetooth module 69 according to the RS-232C standard.

The Bluetooth module 67 and the Bluetooth module 69 are connected to the portable display pad 20 shown in FIG.
This is a configuration in which an RS-232C connector is added to the Bluetooth module 33, and an antenna 68 and an antenna 70 are connected respectively.

The RS-232C 64 and the Bluetooth module 67 are connected to each other, and the RS-232C 65 and the Bluetooth module 69 are connected to each other by an RS-232C cable.

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 An
notation) 80, MBFT (Multipoint Binary File Tran)
sfer) 81, NC (Node Controller) 82, GCC (Gener
ic ConferenceControl) 83, SDE (Service Discover)
y Entity) 84, LMCE (Link Manager Control Entit)
y) 85 is an application, and in addition, there is a user application (not shown).

The SIEA 80 is a whiteboard application for rewriting a whiteboard area shared by all terminals and for performing various drawing operations.
Recommendation T. 126 is performed.

The MBFT 81 is an application for transferring files such as conference materials. 127 is performed.

The NC 82 and the GCC 83 are conference control applications in which a terminal connected to the Bluetooth network executes a conference under the control of the chairman and manages a list of terminal information such as capabilities and attributes of each terminal. ITU-T Recommendation T. An operation according to H.124 is performed.

The SDE 84 is an application that checks services that can be used with the partner terminal and checks the characteristics of those services.

The LMCE 85 is an application for passing a command to the link manager 94 when exchanging a master and a slave, for example, other than the RFCOMM and SDP protocols.

MCS (Multipoint Communication Servi)
ce) 86 implements a multi-point session layer protocol, for example, ITU-T Recommendation T.86. An operation conforming to H.125 is performed.

X.224 (87) complies with ITU-T Recommendation X.224. 2
It is compliant with the 24 class 0 and executes a transport layer protocol for performing flow control of data transfer and the like.

T. 70NULL88 complies with ITU-T Recommendation T.70. Executes a network layer protocol conforming to 70 NULL.

[0090] PPP (Point to Point Protocol) 89
Implements a data link layer protocol over a serial line.

RFCOMM (RF COMMunication) 90 is
L2CAP (Logical Link Control and Adaptation Prot)
ocol) is a protocol for emulating a serial port over the protocol.

SDP (Service Discovery Protocol) 91
Provides the application with a method of confirming services that can be used with the partner terminal and examining the characteristics of those services.

The L2CAP 92 executes multiplexing of an upper layer protocol, division and assembly of a data packet (L2CAP packet), and the like.

HCI (Host Controller Interface) 93
Is the host (CPU 3) in the portable display pad 20.
0) and the Bluetooth module 33, and is an HCI API (Application Program Interface).
rface) and a U functioning as a transport layer between the host (CPU 30) and the Bluetooth module 33.
It is composed of an ART and a hardware driver of the Bluetooth module 33.

The link manager 94 executes an LMP (Link Manager Protocol) for setting a link and controlling a link during a master-slave switching operation.

The baseband 95 executes establishment of a physical link, transmission and reception of various packets, and the like.

The physical layer 96 is composed of GFSK (Gaussian Fr
It performs signal modulation by frequency shift keying) and spread spectrum communication by frequency hopping.

Here, the frequency band used by Bluetooth is 2
471 to 2497 MHz (Japan), number of hopping channels is 23 (1 MHz interval), hopping speed is 160
0 hops / sec. The channel is 625 μsec.
The master terminal starts transmission of packets in even-numbered time slots, and the slave terminal starts transmission of packets in odd-numbered time slots.

In the above protocol configuration, the UART driver, the hardware driver of the Bluetooth module 33 (in the HCI 93), the link manager 94, the baseband 95, and the physical layer 96 are mounted on the Bluetooth module 33. Other than the above are software modules (tasks) executed by the CPU 30, which are stored in the hard disk 40 in advance as execution programs.

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 is different from the protocol configuration of the portable display pad 20 shown in FIG. , MC that controls MCS
SCE (Multipoint Communication Service Control En
tity) 97, except that the portable display pad 20
Is the same as the protocol configuration.

However, in the Bluetooth repeater 1, HC
I93 is an interface between the host (CPU 60) and the Bluetooth module 67 and the Bluetooth module 69, and includes an HCI API, a host (CPU 60).
And Bluetooth module 67, Bluetooth module 69
RS-2 functioning as a transport layer between
32C, a Bluetooth module 67, and a hardware driver of the Bluetooth module 69.

In the protocol configuration shown in FIG.
2C driver and hardware driver for Bluetooth module 67 and Bluetooth module 69 (HCI 93
Medium), link manager 94, baseband 95, physical layer 96, Bluetooth module 67, Bluetooth
It is mounted on the module 69 and the rest
0 is a software module (task) executed in advance and stored in the ROM 63 as an execution program in advance.

Bluet up to the formation of a Bluetooth network
ooth Communication Sequence Next, a Bluetooth communication sequence until a Bluetooth network (piconet) is formed will be described with reference to the piconet 16 shown in FIG.

Establishing communication connection with Bluetooth repeater In this communication sequence, the master terminal (chairperson terminal)
2 is a master terminal 2 by an inquiry procedure.
Recognize all slave terminals that can communicate with That is, the master terminal 2 repeatedly transmits the ID packet, and the slave terminal receiving the ID packet transmits an FHS packet including the Bluetooth device address (BD_ADDR), the system clock of the own terminal, and the like. Thereby, the master terminal 2 determines the number of received FHS packets (BD_ADDR
From the number of slave terminals).

In the piconet 16 shown in FIG. 1, the chair terminal 2 recognizes seven slave terminals (one of which is the Bluetooth module of the Bluetooth repeater 1). The recognized number of slave terminals and the received device address BD_ADDR
Is stored in the main memory 31.

Next, the master terminal 2 first searches for the Bluetooth repeater 1 from the recognized slave terminals, and first connects to the Bluetooth repeater, if any. That is, the terminal having the device address BD_ADDR previously stored in the main memory 31 is sequentially connected to the link manager (link layer) to establish a connection and perform a service discovery sequence operation to check whether each is a Bluetooth repeater. I do. Note that the Bluetooth repeater 1 has a Bluetooth relay service (a uniquely defined service not defined by the Bluetooth standard).

In this operation, if the partner has the Bluetooth relay service, the master terminal 2 establishes a communication connection with the partner terminal (the Bluetooth relay 1) to the application. Also, the opponent is Bluetoot
If the relay terminal does not have the h relay service, the master terminal 2 disconnects the link layer connection. The details of the procedure for establishing a communication connection are the same as the operation sequence between portable display pads described below.

Establishing a communication connection with a plurality of slave terminals Next, the master terminal 2 establishes a communication connection with the six slave terminals sequentially. The procedure for establishing a communication connection will be described.

The master terminal 2 receives the device address BD_ADDR received from the slave terminal during the inquiry procedure.
LAP (Lower Address Part)
An ID packet including a synchronization word derived from is transmitted. On the other hand, the slave terminal (any of 3 to 8; hereinafter, omitted) has its own device address BD_ADDR.
When an ID packet including a synchronization word derived from is received, it responds with an ID packet.

Next, the master terminal 2 sends the active member address (AM_ADD), which is the identification number of the slave terminal.
The FHS packet in which R) is set to 1 is transmitted. When the slave terminal receives this, it 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.

Next, the master terminal 2 transmits a POLL packet, and the slave terminal responds with a NULL packet to establish a connection of the baseband layer.

Then, the master terminal 2 and the slave terminal shift to a connection establishment sequence between link managers (link layer).

First, the master terminal 2 performs LMP_host_connect
An ion_req PDU (Protocol Data Unit) is transmitted, and the slave terminal responds with an LMP_accepted PDU.

Next, the master terminal performs LMP_features_req
The slave terminal sends a PDU and the LMP_features_res PDU
To exchange information about the functions of the own terminal.

Next, the master terminal 2 performs LMP_setup_comp
Send lete PDU, slave terminal is LMP_setup_complete
In response to the PDU, a connection between the link managers (link layer) is established.

Subsequently, the master terminal 2 executes a service discovery sequence.

The application of the master terminal 2 is S
When a service discovery request is issued to the DP task, S
The DP task issues a connection request (L2CA_ConnectReq event) to the L2CAP task. Upon receiving this request, the L2CAP task transmits a Connection Request packet.

When the L2CAP task of the slave terminal receives this packet, it sends an L2CA_ConnectInd to the SDP task.
Pass the message and connect to master terminal 2
The SDP connection is established in response to the response packet.

Next, the SDP task issues a configuration request (L2CA_ConfigReq event) to the L2CAP task. When the L2CAP task receives this request,
Configuration Reques including configuration parameters such as quality of service (QoS)
Send t packet.

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 containing configuration parameters.

Next, the SDP task of the master terminal 2 is as follows:
UUID indicating that it is an electronic conference service (a uniquely defined service not defined by the Bluetooth standard)
Sends SDP_ServiceSearchRequest PDU including (Service unique identifier) in the ServiceSearchPattern parameter, and the SDP task of the slave terminal performs SDP_ServiceSearchR
Respond with esponse PDU.

When the application of the master terminal confirms that the currently connected slave terminal is the electronic conference terminal, it issues a connection request to the MCS task. This connection request is sequentially issued to the lower layer, and a PPP connection, an X.224 connection, and an MCS connection are sequentially established. Then, a connection is established between the entities of the conference applications GCC, SIEA, and MBFT, and communication between the entities becomes executable.

The communication sequence up to the point where the drawing data transfer and the file transfer can be performed between the master terminal 2 and one slave terminal (for example, the slave terminal 3) using the MCS connection has been described above. The master terminal 2 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 communicates with the master terminal 2 and the slave terminals 3 to 8 and the Bluetooth relay. Table 1 (Bluetoo
(using th module 67).

Operation of Bluetooth Repeater 1 Subsequently, the Bluetooth repeater 1 starts operation as a master using the Bluetooth module 69 in parallel with operation as a slave. That is, the Bluetooth repeater 1 sequentially establishes a communication connection with the slave terminals 9 to 15 by the same operation as described above, and
A piconet using the oth repeater 1 (using the Bluetooth module 69) as a master is formed.

In this way, a Bluetooth network composed of two piconets with the Bluetooth repeater 1 as a relay point is formed.

Next, Bluetoot consisting of two piconets
h An MCS connection between all terminals connected to the network and a connection between entities such as GCC as a conference application will be described.

First, the MCS connection will be described. The MCS 86 shown in FIGS. 5 and 6 is called an MCS provider. Blueto consists of two piconets
A view of the oth network as a network between MCS providers is called an MCS domain.

The MCS domain in the network configuration shown in FIG. 1 has a hierarchical structure as shown in FIG. The master terminal 2, which is the chair, is the top MCS provider and is located at the highest layer. The slave terminals 3 to 8 and the Bluetooth repeater 1 are located in an intermediate layer, and the slave terminals 9 to 15 are located in the lowest layer.

After the terminal establishes the MCS connection,
Attach to CS domain. By this attachment, each terminal acquires an MCS user ID that is a terminal identifier in the MCS domain.

Next, each terminal subscribes to the MCS channel. The MCS channel is an address in the MCS domain, and all terminals subscribed to the same channel receive data sent to that channel. Here, when the slave terminal 9 transmits data to the channel to which all the terminals are subscribed, the data is first transferred to the Bluetooth repeater 1, and the Bluetooth repeater 1 transmits this data to the slave terminals 10 to 15 To the top M
Transfer to the master terminal 2 which is a CS provider. Then, the master terminal 2 transfers this data to the slave terminals 3 to 8.

As described above, when all terminals subscribe to the same channel, data can be transmitted to all terminals. Note that 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.

Next, the conference control application G
The CC and the node controller (NC) will be described. The GCC 83 shown in FIGS. 5 and 6 is called a GCC provider. The GCC provider of the terminal that is the top MCS provider is called a top GCC provider. When each GCC provider joins the meeting,
A list of conference applications such as IEA and MBFT and terminal information (conference node list) such as an MCS user ID which is a terminal identifier in the MCS domain are stored in all other G nodes.
Send to CC provider. Note that this broadcast transmission is realized by transmitting data to the MCS channel to which all terminals have subscribed. The terminal information is received by each terminal and managed by the NC 83. The GCC also controls the assignment of chairmanship, etc., and at the start of the meeting, the top GCC provider has the chairmanship. The node controller (NC83) sets G in accordance with a request from the user.
It issues various primitives to the CC 83, and manages application lists and conference node lists of its own terminal and all other terminals.

Since the Bluetooth repeater 1 has no GCC,
MCS user I which is a terminal identifier in the MCS domain
Terminal information such as D is not transmitted to other terminals, and the chair terminal
The uetooth repeater 1 is not regarded as a terminal participating in the conference.

In this way, under the chairman's control, the conference material file, handwritten drawing data, and the like are transmitted from each terminal to all terminals or to individual terminals, and an electronic conference is performed.

FIG. 8 shows the general operation flow of the chair terminal 2 (portable display pad 20), which is the master, and FIG.
FIG. 9 shows a schematic operation flow in the repeater 1 described above.

General operation flow in master terminal Referring to FIG. 8, in this operation, master terminal 2
Is the device address BD_ADDR of each slave terminal within the communication range by the inquiry means, and the BD_ADDR
(The number M of slave terminals) is obtained and stored (step S101).

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.

As described above, first, assuming that n = 1, the master terminal 2 establishes a connection between the n-th (= 1) th slave terminal having the BD_ADDR and the link manager to establish a link (step). S103). Furthermore,
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).

If the result of the determination in step S105 is that the nth slave terminal is not the Bluetooth repeater 1 (No in step S105), the master terminal 2 disconnects the link with this slave terminal (step S108).

The master terminal 2 determines whether or not the current value of n is equal to the number M of the slave terminals within the communicable range (step S109), and if they are equal (Yes in step S109). The process proceeds to step S111, and if not equal (No in step S109),
The value of n is incremented by 1 (step S110),
It returns to step S103.

On the other hand, if the result of the determination in step S105 is that the n-th slave terminal is the Bluetooth repeater 1 (Yes in step S105), the master terminal 2
Sequentially establishes a connection of each layer (communication connection to the application) to the slave terminal (step S106), subtracts 1 from the number M of slave terminals (step S107), and proceeds to step S111.
Move to.

As described above, the operations up to this point are repeatedly executed until all slave terminals within the communicable range are executed, or until the connection with the Bluetooth repeater 1 is established.

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, a connection is made with the nearest Bluetooth repeater. A description of how the master terminal 2 determines the closest Bluetooth repeater from among the plurality of Bluetooth repeaters will be omitted.

Next, in step S111, the master terminal 2 first substitutes 1 for the value of k (step S11).
1). This is because, similarly to the above, the subsequent processing is executed for all slave terminals except the Bluetooth repeater 1 within the communicable range.

Next, the master terminal 2 establishes a communication connection between the slave terminal having the k-th device address and the link manager (step S112), and further executes a service discovery sequence (step S113).

Thereafter, the master terminal 2 determines whether or not the slave terminal of the other party is a terminal participating in the conference managed by the master terminal 2 (step S114). If the slave terminal is a participating terminal (step S114). Yes), the communication connection (communication connection to the application) between the slave terminal and each layer is sequentially established (step S115), and the process proceeds to step S118. Also,
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 repeater 1 in the communicable range. (Step S11
6) If equal (Yes in step S116), the process proceeds to step S121. If not equal (No in step S116), the master terminal 2 sets the value of k to 1
Increment (step 117), step S11
Move to 2.

In step S118, it is determined whether or not the number of slave terminals currently establishing a communication connection with the master terminal 2 is equal to the limit number (seven) in the piconet (step S118). In this case (No in step S118), it is determined whether or not the value of k at the present time is equal to the number M of slave terminals excluding the Bluetooth repeater 1 in the communicable range (step S1).
19) If they are 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 one (step 120), and proceeds to step S1.
Move to 12.

In the step S121, the master terminal 2
Performs a broadcast transmission of data to be transmitted to all slave terminals and a data transmission to an individual destination using an MCS user ID which is a terminal identifier in the MCS domain, and also performs an operation having a chairman's right. (Step S12
1).

General operation flow in Bluetooth repeater The general operation flow of the Bluetooth repeater 1 in this embodiment will be described with reference to FIG.

Referring to FIG. 9, in this operation, Blue
First, the tooth repeater 1 operates as a slave to establish a communication connection in response to a request from the master terminal (chairperson terminal) 2 (step S201). This operation is an operation corresponding to master terminal 2 in the operation shown in FIG.

Next, by operating as the master, the Bluetooth repeater 1 obtains the number M of slave terminals within the communication range with itself and the device address BD_ADDR of each slave terminal by the inquiry procedure. It is stored (step S202). This operation is similar to the operation of master terminal 2 in FIG.

Next, the Bluetooth repeater 1 first substitutes 1 for the value of n (step S203). This is to execute the subsequent processing for all slave terminals within the communicable range.

After substituting 1 for n, the Bluetooth repeater 1 establishes a communication connection between the slave terminal having the n-th device address and the link manager (step S204), and further executes a service discovery sequence. Execute (step S205).

Thereafter, the Bluetooth repeater 1 determines whether or not the slave terminal of the partner is a terminal participating in a conference managed by the master terminal 2 (step S206), and if it is a terminal participating in the conference (step S206). Yes),
The communication connection (communication connection to the application) of each layer with the slave terminal is sequentially established (step S207), and the process proceeds to step S210.
If the slave terminal is not a participating slave terminal (step S2
06), the Bluetooth relay device 1 determines whether or not the current value of n is equal to the number M of slave terminals within the communicable range (step S208), and if they are equal (Yes in step S208), It moves to step S213. If they are not equal (N in step S208)
o), the Bluetooth repeater 1 increments the value of n by 1 (step 209), and proceeds to step S204.

In step S210, the current Bluetooth
h The number of slave terminals that have established a communication connection with the repeater 1 is the maximum number in the piconet (7).
Is determined (step S210), and if not equal (No in step S210), it is determined whether the current value of n is equal to the number M of slave terminals within the communicable range (step S210). If the values are equal (Yes in step S211), the process proceeds to step S213. If they are not equal (N in step S211)
o), the Bluetooth repeater 1 increments the value of n by 1 (step S212), and proceeds to step S204.

At step S213, the MCS provider of the Bluetooth repeater 1 executes data transfer to the slave terminal (step S213).

In the above described embodiment, the case where the Bluetooth repeater 1 has two Bluetooth modules has been described, but the Bluetooth repeater 1 has three or more Bluetooth modules.
It can be applied to the case with th module. For example, if the Bluetooth repeater 1 has three Bluetooth modules and each Bluetooth module is connected to a different piconet, one Bluetooth module operates as a slave of the master terminal 2 which is the chair terminal, and the other two Each of the Bluetooth modules operates as a master. Thereby, an MCS domain is formed between the terminals connected to the three piconets.

[Second Embodiment] Next, a second embodiment of the present invention will be described in detail with reference to the drawings.

In this embodiment, the bluetooth shown in the first embodiment is used.
A directional antenna is used as an antenna connected to each Bluetooth module of the oth repeater 1, and two Bluetooth modules are built in the main body of the Bluetooth repeater 1. FIG. 10 shows a hardware configuration of the Bluetooth repeater 1 in this case.

In FIG. 10, the CPU 60, clock 61, main memory 62, ROM 63, and CPU bus 66 are shown in FIG.
Are the same as the respective components of the Bluetooth repeater 1 of the first embodiment shown in FIG.

In FIG. 10, UART 71 and UART 71
72 is the same as the UART 32 shown in FIG.
The uetooth module 73 and the Bluetooth module 75 are the same as the Bluetooth module 33 shown in FIG.

However, in FIG. 10, the antennas 74 and 76 are directional antennas. As the directional antennas, for example, those using a planar antenna having a corrugated structure as shown in FIG. I do. This planar antenna has a corrugation groove depth CL (Corrugatio).
By changing the dimension of (n Length), it is possible to change the directivity range of the E-plane (denoted as E-plane in the figure) which is a radio wave emission surface. The E plane is a plane including the direction in which the electric field oscillates (polarization direction) as shown in FIG. FIG. 11 shows a case where the plane of the planar antenna is in the vertical direction. The antennas 74 and 76 shown in FIG. 10 are mounted so that the E-plane is horizontal, that is, the plane of the planar antenna is horizontal.

Further, the Bluetooth module 73 is set so that the directional directions of the antenna 74 and the antenna 76 are different from each other.
And the Bluetooth module 75 are installed. Two Bluet
FIG. 12 shows an example of the range of the transmission radio wave of each antenna when the ooth module is used.

Referring to FIG. 12, by arranging antennas 74 and 76 as described above, in this embodiment, it is possible to prevent the areas covered by each antenna from overlapping more than necessary. It becomes possible.

Note that the two Bluetooth modules are Bluet
Instead of being built in the main body of the ooth repeater 1, the length of the RS-232C cable is shortened with the configuration shown in FIG.
The configuration may be such that the Bluetooth modules are installed such that the directional directions of the antennas are different from each other.

Also, 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.

[Third Embodiment] Next, in the Bluetooth network composed of two piconets shown in the first embodiment, the master terminal 2 serving as the chair transfers the chairman's right to another terminal during a communication conference. Will be described below.

Now, in the Bluetooth network shown in FIG. 1, a whiteboard application (using SIEA80), a file transfer application (using MBFT81), and a conference control application (using GCC83) are executed between all terminals. State.

Here, when the master terminal 2 transfers the chairmanship to the slave terminal 10 connected to the piconet 17, the NC 82 transmits the GCC 83 to the GCC 83 including the node ID (same as the MCS user ID) of the slave terminal 10. -CONDUC
Pass the TOR-GIVE-request primitive.

The GCC 83 sets these parameters in the data area, and sets the channel ID to the slave terminal 1
The MCS-SEND-DATA-request primitive in which the node ID of 0 is set is passed to the MCS 86.

In the MCS 86, the specified channel ID
Is transmitted to the slave terminal 10.
Sent to

When the slave terminal 10 receives this data, the NC 82 sends the GCC-CONDUCTOR-GIVE to the master terminal 2.
-Return a response and send a GCC-CONDUCTOR-ASSIGN- indication to all terminals to inform them that they are the new chair.

Thus, the chair terminal in the MCS domain is changed from the master terminal 2 to the slave terminal 10. After that, the master terminal 2 receives GCC, MCS,
X.224, the connection of each layer of PPP is disconnected.

Next, the master terminal 2 exchanges the master / slave with the Bluetooth repeater 1.

First, the link manager 94 sets LMP_swi
Transmits the tch_req PDU, and transmits the LMP_acce
Receive the pted PDU. Then, a master / slave exchange operation is performed in baseband 95. That is,
The master terminal 2 and the Bluetooth repeater 1 first invert the TX timing and the RX timing.
The uetooth repeater 1 becomes the master.

Then, the terminal 2 which has become a slave is
A sequence for operating in synchronization with the clock of the tooth repeater 1 is executed.

[0177] Then, the Bluetooth repeater 1 receives the new AM_AD.
The DR is included in the FHS packet and transmitted to the terminal 2.

After that, the Bluetooth repeater 1 transmits the operation sequence for the slave side to adjust to the new master clock and the transmission of the new AM_ADDR to the other terminals (terminals 3 to 8) connected to the piconet 16 to each slave terminal. Execute each time.

In this manner, the master of the piconet 16 is switched from the terminal 2 to the Bluetooth repeater 1.

Thereafter, the terminal 2 sets the link manager 94
To send an LMP_detach PDU to leave the Bluetooth network.

Next, 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.

Then, the Bluetooth repeater 1 and the slave terminal 10 invert the TX timing and the RX timing, and at this time, the terminal 10 becomes the master.

[0183] Then, the Bluetooth repeater 1 serving as a slave executes a sequence for operating in synchronization with the clock of the terminal 10.

Then, terminal 10 sets new AM_ADDR to FH
The packet is transmitted to the Bluetooth repeater 1 while being included in the S packet.

Thereafter, the terminal 10 sends to each of the other terminals (terminal 9, terminal 11 to terminal 15) connected to the piconet 17 an operation sequence for the slave side to adjust to the new master clock and transmission of a new AM_ADDR to each slave. Execute sequentially for each terminal.

Thus, 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 the electronic conference.

FIG. 13 shows the general operation flow of the terminal 2, FIG. 14 shows the general operation flow of the Bluetooth repeater 1, and FIG. 15 shows the general operation flow of the terminal 10.

First, a schematic operation flow in the terminal 2 will be described with reference to FIG. 13, in which the operation of the terminal 2 from switching from the master to the slave and leaving the Bluetooth network is described.

Referring to FIG. 13, in the present operation, terminal 2 first transfers the chairperson's right to slave terminal 10 (step S301).

Next, the terminal 2 receives GCC, MCS, X.22
4. The communication connection of each layer of PPP is disconnected (step S302), and thereafter, the exchange operation of the master / slave with the Bluetooth repeater 1 is executed (step S30).
3).

By operating in this manner, the terminal 2 functions as a slave, so that even if the terminal 2 leaves the Bluetooth network, the function of the Bluetooth network itself is not impaired. Therefore, after this, the terminal 2
Leave the Bluetooth network (step S30)
4).

[0192] Schematic Operation Flow in Bluetooth Repeater [0192] The operation when the Bluetooth repeater 1 switches the master from the terminal 2 to the terminal 10 will be described with reference to FIG.

Referring to FIG. 14, in this operation, Bl
The uetooth repeater 1 first disconnects the communication connection of each layer of X.224 and PPP established with the terminal 2 (step S401).

Next, the Bluetooth repeater 1 executes a switching operation from the master to the slave for the terminal 2 (step S402).

Then, the Bluetooth repeater 1 connects to the terminal 10
, An exchange operation from the slave to the master is performed (step S403).

Thus, the master for the Bluetooth repeater 1 is switched from the terminal 2 to the terminal 10.

Outline of Operation Flow in Terminal 10 An outline of the operation when the terminal 10 switches from the slave to the master will be described with reference to FIG.

Referring to FIG. 15, in this operation, when terminal 10 first receives the chairman's right from terminal 2, it becomes the chair terminal of the plenary session (step S501).

Next, the terminal 10 performs an operation of switching from the slave to the master with the Bluetooth repeater 1, and the terminal 10 itself becomes the master (step S502).

Thereafter, the terminal 10 becomes the top MCS provider in the MCS domain (step S50).
3).

As a result, the terminal 10 switches from the slave to the master and can operate.

[Fourth Embodiment] The fourth embodiment shown in FIG.
There are multiple tooth repeaters and BL between Bluetooth repeaters
The case where the connection is made via the uetooth network will be described below.

In this embodiment, FIG. 16 shows an example of a Bluetooth network in a case where three Bluetooth repeaters exist.

Referring to FIG. 16, the blue color according to the present embodiment is shown.
tooth network is Bluetooth repeater 1, Bluetooth
The repeater 100, the Bluetooth repeater 110, the master chair terminal 2, and 25 slave terminals (3 to 13, 12
1 to 127, 131 to 137). In FIG. 16, M represents a master and S represents a slave.

The network configuration shown in FIG. 16 has a hierarchical structure as shown in FIG. In this hierarchical structure, the master terminal 2 which is the chair is the highest layer, the Bluetooth repeater 1
And the slave terminals 3 to 8 are in the second layer, Blueto
The oth repeater 100, the Bluetooth repeater 110, and the slave terminals 9 to 13 are the third layer, the slave terminal 1
21 to the slave terminals 127 and 131 to 137 are located in the fourth layer.

FIG. 17 shows M in the MCS domain.
It is also a hierarchical structure of CS providers. That is, the master terminal 2 which is the chair is the top MCS provider,
Located at the highest level. Therefore, all the terminals connected to this MCS domain operate under the chairman's control, and the conference material file and the handwritten drawing data are transmitted from each terminal to all the terminals or to the individual terminals. A meeting is performed.

[Other Embodiments] In each of the above embodiments, the protocol on the RFCOMM 90 is PP
P, T. Although the case where 70NULL and X.224 are used has been described, for example, another protocol such as PPP or TCP / IP may be used.

The present invention can be applied to applications other than the electronic conference.

However, each of the above embodiments is merely an embodiment of the present invention, and the present invention can be variously modified and implemented without departing from the gist thereof.

[0210]

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. The multiple Blues of the repeater
One of the tooth modules is used as a slave, and the other is used as a master, so that data transmission and reception can be performed between a plurality of piconets, thereby performing data communication with a small delay between the plurality of piconets. Becomes possible.

That is, according to the first aspect of the present invention, the Bluetooth for relaying and transferring data between a plurality of piconets
Since a repeater 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, the convenience in the case where handwritten data is broadcast to many terminals in real time at a meeting or a lecture is improved.

[0212] Further, according to the invention of claim 2, out of the plurality of Bluetooth modules, the Bluetooth module connected to the piconet where the master terminal exists is set as a slave, and the other Bluetooth modules are set as masters, This makes it possible to perform data communication with a small delay between a plurality of piconets. In addition, terminals included in the piconet other than the piconet including the master terminal are set as slaves of the Bluetooth
By using the luetooth repeater as a slave of the master terminal, substantially all terminals can be made slave terminals of the master terminal.

Further, according to the invention of claim 3, a terminal identifier for a session connection of a terminal included in the piconet to which the master Bluetooth module belongs is transmitted to the master terminal.
Characterized in that the session protocol is executed based on the terminal identifier, whereby all the terminals connected to the Bluetooth network composed of a plurality of piconets execute the session protocol using the terminal identifier for the session of another terminal. Therefore, it is possible to improve the flexibility of network construction.

Further, according to the invention described in claim 4, the master terminal exchanges a master with any one of the slave terminals included in the plurality of piconets.
This allows, for example, if the chair terminal acting as the master leaves the network for any reason,
The subsequent chair will be transferred to a terminal connected to the same piconet or to a terminal connected to another piconet, and the terminal to which the transfer will be made the master will decrease the data transmission efficiency of the Bluetooth network in such a case. Can be prevented.

Further, according to the invention of claim 5, the plurality of piconets have a hierarchical structure in which the piconet including the master terminal is the highest level, and one of the plurality of Bluetooth modules of the repeater is provided. Include a Bluetooth module in a higher-level piconet than other Bluetooth modules and include it in a higher-level piconet
By transmitting and receiving data between a plurality of piconets by using a Bluetooth module as a slave and another Bluetooth module as a master,
By using a plurality of Bluetooth repeaters and providing a hierarchical structure between the Bluetooth repeaters, even if the terminals are present in a wide range, the terminals can be connected to the Bluetooth network.

Further, according to the invention of claim 6, there is provided a plurality of Bluetooth modules connected to the piconet, wherein one of the plurality of Bluetooth modules is set as a slave and the other is set as a master. By
Data communication can be performed with a small delay between a plurality of piconets.

That is, according to the invention of claim 6, the Bluetooth for relaying and transferring data between a plurality of piconets
Since a repeater 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, the convenience in the case where handwritten data is broadcast to many terminals in real time at a meeting or a lecture is improved.

Further, according to the seventh aspect of the present invention, among a plurality of Bluetooth modules, a Bluetooth module connected to a piconet where a master terminal exists is set as a slave, and another Bluetooth module is set as a master, This makes it possible to perform data communication with a small delay between a plurality of piconets. In addition, terminals included in the piconet other than the piconet including the master terminal are set as slaves of the Bluetooth
By using the luetooth repeater as a slave of the master terminal, substantially all terminals can be made slave terminals of the master terminal.

[0219] Further, according to the invention of 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 layer, a layer higher than the other Bluetooth modules. The Bluetooth module included in the as a slave, characterized in that the other module is a master, thereby using a plurality of Bluetooth repeaters,
By having a hierarchical structure between each Bluetooth repeater, even if the terminals exist in a wide area,
Can be connected to a Bluetooth network.

Further, according to the ninth aspect of the present invention, at least one of a plurality of antennas connected to each of the plurality of Bluetooth modules is an antenna having directivity, whereby the Bluetooth By providing directivity to the multiple antennas used by the repeater, and by directing them in different directions, radio wave interference is reduced, and more distant positions with the same transmission power compared to non-directional antennas Wireless communication with a terminal located at

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating 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 the first embodiment of the present invention.

FIG. 3 is a block diagram showing a hardware configuration of the portable display pad according to the first embodiment of the present invention.

FIG. 4 is a block diagram illustrating 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 the 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 illustrating 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 a chair 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 illustrating a hardware configuration of a Bluetooth repeater according to a second embodiment of the present invention.

FIG. 11 is a diagram illustrating a radiation surface of a radio wave 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 illustrating a schematic operation of the terminal 2 according to the third embodiment of the present invention.

FIG. 14 is a flowchart illustrating 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 terminal (master terminal, chair terminal) 3 to 15, 121 to 127, 131 to 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. 70 NULL 89 PPP 90 RFCOMM 91 SDP 92 L2CAP 93 HCI 94 Link Manager 95 Baseband 96 Physical Layer (RF) 97 MCSCE

Claims (9)

[Claims] 1. 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 one of a plurality of Bluetooth modules included in the repeater is used. By being a slave and the other being a master,
A wireless communication method comprising transmitting and receiving data between a plurality of piconets. 2. A connection to a piconet in which the master terminal is present among the plurality of Bluetooth modules.
2. The wireless communication method according to claim 1, wherein the Bluetooth module is a slave and another Bluetooth module is a master. 3. A terminal identifier for a session connection of a terminal included in the piconet to which the master Bluetooth module belongs is transmitted to the master terminal.
The wireless communication method according to claim 2, wherein the master terminal executes a session protocol based on the terminal identifier. 4. The wireless communication method according to claim 1, wherein the master terminal exchanges a master with any one of the slave terminals included in the plurality of piconets. 5. The plurality of piconets have a hierarchical structure in which a piconet including a master terminal is located at the highest level, and one of the plurality of Bluetooth modules included in the repeater is replaced by another Bluetooth module. Is also included in a higher-level piconet, a Bluetooth module included in the higher-level piconet is used as a slave, and the other Bluetooth module is used as a master, thereby transmitting and receiving data between a plurality of piconets. The wireless communication method according to claim 1, wherein 6. A repeater comprising a plurality of Bluetooth modules connected to a piconet, wherein one of the plurality of Bluetooth modules is a slave and the other is a master. 7. A Bluetooth module connected to a piconet in which a master terminal exists among the plurality of Bluetooth modules.
7. The repeater according to claim 6, wherein the tooth module is a slave and another Bluetooth module is a master. 8. In a Bluetooth network including a plurality of piconets having a hierarchical structure in which a piconet including a master terminal is the highest level, another Bluetooth
7. The repeater according to claim 6, wherein a Bluetooth module included in a hierarchy higher than the module is set as a slave, and another module is set as a master. 9. The antenna according to claim 6, wherein at least one of the plurality of antennas connected to each of the plurality of Bluetooth modules is a directional antenna.
The repeater according to any one of the preceding claims.