JP2000209221A - Radio communication method, radio communication terminal for executing the method, and medium with program for realizing the methods stored therein - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently utilize a communication band and conduct radio control by simplifying a communication procedure and allowing a subordinate layer to process efficient medium access. SOLUTION: A plurality of terminals 1-3 use a radio band (frame) 22 in common, when conducting communication by the terminals in this radio communication method. When the terminals make communication, they use a synchronous word 21 to share a communication band in common, they use one packet length (23) that is a fixed bandwidth in the unit of the bandwidth shared in common by them, and number of cells are used to assign the band used by each terminal. Furthermore, the terminals connected to a network sequentially transmits the synchronous word, to ensure the synchronization of the entire network. An address map field is set in the synchronous word. When each terminal participates in/retires from the network, each terminal discriminates its own terminal address from the address map filed. Moreover, the synchronous word is provided with a resource map field corresponding to cells, and each terminal in the case of communication discriminates the idleness of the resource from the resource map filed to set up the radio band.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless communication method and a wireless communication terminal having a function of executing the wireless communication method, and more particularly to a wireless LAN system and a home network in which a wireless band is shared and used by a plurality of terminals. Applied to the system.

[0002]

2. Description of the Related Art At present, a LAN (local area network) has become commonplace in offices, and is being spread to small stores and homes. Also, the network configuration method is to use wireless, wireless, or conventional coaxial cables or twisted pair wires.
A method using IrDA or the like has also appeared.

[0003] As an example, a wireless LAN using a 2.4 GHz band radio specified in IEEE 802.11.
Media access control (MAC) method and IrDA
The method of the link access protocol of the infrared communication method using the method will be described.

FIG. 10A is a diagram showing a protocol of a MAC layer defined by IEEE 802.11.
This protocol is called CSMA / CA + ACK and I
A procedure for performing radio-specific control is added to CSMA / CA of Ethernet MAC, which is a standard of a wired LAN specified by EEE802.3.

[0005] CS specified in IEEE 802.3
MA / CA is a method of monitoring the state of a signal on a shared physical medium and transmitting data 101 if no one is using it. As a result of monitoring the signal state, if there is a signal on the physical medium, the monitoring state is re-entered after waiting for a certain period of time. CSMA / CA + ACK defined in IEEE 802.11 additionally includes a transmission request RTS 102, a corresponding response CTS 103, and a data reception acknowledgment A in order to solve a wireless-specific problem.
Use CK104 to avoid radio collisions,
This ensures reliable data transmission.

FIG. 10 (B) is a diagram showing a protocol of an ASK link access layer used for communication using IrDA. As in FIG. 10A, a transmission request / response and data ACK are required for data transmission.

When communication is performed using such a wireless or IrDA medium, communication capacity and communication speed are limited as compared with wired communication, so that efficient communication control is required. On the other hand, when wireless or IrDA is used, there is no cable connection compared to wired communication, and communication between a plurality of terminals can be easily performed. Therefore, communication control is performed so that a plurality of terminals can be used simultaneously.

However, in this communication control, when a terminal performs communication, the procedure is based on a handshake (request and response) with a partner terminal or a communication master in a network, and a reliable control can be performed. However, the efficiency of the control procedure is poor, which causes a decrease in throughput for the terminal to perform communication.

When a network is managed by a master, the master is always required on the network.
When the protocol such as switching of the master or setting of the submaster becomes complicated, or when the master is fixed, it is not possible to freely join and leave the network.

[0010] Furthermore, in order to share a wireless band among a plurality of terminals, a method of effectively using the band by using frequency spreading or the like has been proposed. However, a wireless control method is complicated and an enormous scale of hardware is required. Needed ware. In addition, since the data traffic of the devices connected to the network is diverse and the communication form is also various, the conventional communication method in which the frequency and time slot are fixedly assigned deteriorates the use efficiency of the network. was there.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to perform efficient communication control when performing communication using wireless or IrDA as a medium. It is another object of the present invention to perform communication control such that a plurality of terminals can be used simultaneously.

[0012]

Means for Solving the Problems When a plurality of terminals communicate, a plurality of terminals share a wireless band, and when the terminals communicate, a unit for sharing a communication band using a synchronization word and allocating the band. Is fixed in advance as a packet, and the band used by the terminal is allocated by the number of cells. Then, the terminals connected to the network sequentially send out the synchronization word, thereby ensuring synchronization of the entire network, providing an address map field in the synchronization word, and allowing each terminal to join / leave the network. Then, the terminal determines its own terminal address from the address map field.

Further, a resource map field corresponding to a cell is provided in the synchronization word, and when each terminal communicates, a vacancy of resources is determined from the resource map field to secure a radio band.

Further, in the case of a new participation in the network, the synchronization word is transmitted to the network after the number of terminals participating in the network has been set, and an empty space is not provided to transmit the synchronization word. New participation is possible. In the data transmission control, the terminal transmits data to the network according to the bit content of the resource map field in the synchronization word.

According to the first aspect of the present invention, when a plurality of terminals communicate, a plurality of terminals share a wireless band, and when the terminals communicate, the communication band is shared using a synchronization word. Communication method.

According to a second aspect of the present invention, there is provided a radio unit for transmitting / receiving a radio signal, a radio control unit for controlling access to the radio unit, and a partner terminal via a radio signal through the radio unit and the radio control unit. A wireless communication terminal comprising a data processing unit for processing application data for communicating with the wireless communication terminal, wherein the wireless control unit has a function of executing the wireless communication method according to claim 1.

According to a third aspect of the present invention, in the wireless communication method according to the first aspect, when the terminal communicates, the bandwidth is fixed in advance as a unit for allocating the bandwidth as a packet, and the bandwidth used by the terminal is determined by the number of cells. It is made to be allocated by.

According to a fourth aspect of the present invention, in the wireless communication method according to the first aspect, the terminals connected to the network sequentially transmit synchronization words to ensure synchronization of the entire network. is there.

According to a fifth aspect of the present invention, in the wireless communication method according to the first aspect, an address map field is provided in the synchronization word, and when each terminal joins / leaves from the network, the terminal reads the address map field from the address map field. It is also possible to determine the terminal address of the user.

According to a sixth aspect of the present invention, in the wireless communication method according to the third aspect, a resource map field corresponding to a cell is provided in the synchronization word, and when each terminal communicates, the availability of resources is determined from the resource map field. And
This is to secure a wireless band.

According to a seventh aspect of the present invention, in the wireless communication method according to the fourth or fifth aspect, after transmitting the synchronization word by the number of terminals participating in the network, one free space is provided to transmit the synchronization word. By not performing the above, new participation in the network is made possible by using the vacant section.

According to an eighth aspect of the present invention, in the wireless communication method according to the sixth aspect, data is transmitted from the terminal to the network according to the bit content of the resource map field in the synchronization word.

According to a ninth aspect of the present invention, a program for causing a computer to implement the method according to the seventh or eighth aspect is recorded on a computer-readable storage medium.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a wireless LAN or a home network, data traffic of devices connected to the network is various, and communication modes include not only terminal-to-terminal connection but also asymmetric communication and broadcast communication. Exists.

In the wireless communication method of the present invention, efficient media access is processed in a lower layer close to wireless, so that wireless control can be performed efficiently. Also,
It is possible to configure a fully distributed terminal autonomous network, and it is possible to easily manage even if multiple terminals participate in the network without using complicated protocols, and all terminals Operates while monitoring the synchronization word, so joining / leaving from the network is easy. Also, by multiplexing the wireless band with fixed-length packets, resource management on the network is facilitated. Furthermore, each terminal can use a plurality of fixed-length packets, and it is possible to cope with asymmetric communication and broadcast communication in addition to two-way communication.

FIG. 1 shows an embodiment of a communication control method according to the present invention. Figure 1 shows the construction of a network at home
According to the communication method of the present invention, DVD1, ATV2 and GW3
Are connected. In FIG. 1, DVD1 transmits MPEG2 video of a video disk to ATV2. Further, the gateway GW3 is connected to the other party's TV phone 5 via the ISDN line 4, exchanges image / audio information from the other party's TV phone 5 with the ATV 2, and displays an image from the other party on the ATV 2. Therefore, the ATV 2 displays both the video from the DVD 1 and the video from the GW 3. Also, the ATV 2 sends the voice from the ATV 2 to the GW 3.

FIG. 2 shows the transmission order of radio signals and the bands used to realize the communication shown in FIG.
DVD1 sends out video signal T1 following synchronization word SYC21. Even if the video signal T1 is generally coded, the video signal T1 occupies a time corresponding to four packets because a wide band is required.
The video signal T1 transmitted by the DVD1 can receive both the ATV2 and the GW3 as a wireless signal, but the data processing unit of the terminal determines whether or not the video signal T1 can be received.
Receives and reproduces the image. Following the DVD 1, the ATV 2 sends out the audio signal T2. The audio signal T2 is a video signal T1
Since the bandwidth is narrower than that of, the time for one packet is occupied. The receiving operation is the same as described above. Next, G
W3 transmits a signal occupying two packets of the image / audio information T3. If there is a vacancy in the band, a vacant packet enters, and the synchronization word SYC continues after a certain time,
The above operation is repeated.

By performing such an operation, various communication modes can be realized even if a plurality of terminals exist in the network. In addition to two-way communication, asymmetric communication and broadcast-type communication can be realized. Communication becomes possible.

Here, the frame 22 indicates a bandwidth determined by a radio frequency band and a modulation system to be used. For example, when a radio frequency of 2.4 GHz is used, a band of about 10 Mbps can be obtained. The packet 23 is obtained by dividing a frame into fixed time units.

Here, in detail, a non-data section is provided between one frame and the next frame to absorb a time difference generated from an EOF data and a clock error generated in each terminal, which will be described later. I have.

FIG. 3 shows a synchronization management method according to the present invention. In the wireless communication control method of the present invention, since distributed processing is principle, synchronization management is performed by each terminal participating in the network. In the synchronization management according to the present invention, the terminals connected to the network perform synchronization management by sequentially transmitting the synchronization words at the synchronization word transmission timing and rotating.
FIG. 3 is a diagram showing a state of synchronization management in the communication state of FIG. First, the DVD 1 sends out the synchronization word 31a. Subsequently, the packet 2 in the frame 22 shown in FIG.
According to the time ratio of 3, the DVD1, ATV2, and GW3 each transmit transmission data. After there is an empty packet, ATV 2 sends out sync word 32 next. Subsequently, the GW 3 sends out the synchronization word 33. In this way, each terminal sends out the synchronization word in order, so that each terminal can independently manage network synchronization and create signal transmission timing, and at the same time, since synchronization management is distributed, network access to the network is distributed. Participation / withdrawal becomes easy.

The synchronization word is transmitted in accordance with the address map field described below. However, the synchronization word for one frame is not transmitted as 34 for new participation in the network.

FIG. 4 is a diagram showing an address map field of the present invention. The address map field is on the synchronization word, and is transmitted by each terminal as shown in FIG. The address map field grasps the terminals participating in the network and manages the transmission order of the synchronization words by each terminal according to FIG. A terminal participating in the network monitors an address map field transmitted from another terminal, and obtains the smallest address among the free addresses.

FIG. 4 is a diagram for explaining a procedure in which the GW 3 in FIG. 1 acquires an address. The address map field 41a is a state where the GW 3 has not joined the network. Also, the address management table 42a on the GW 3 has no bits set, indicating that it is not participating in the network. When the GW 3 joins the network, the address map field 41a
After confirming the third vacancy from the left, the own address management table 42a sets a bit to the third address [2] from the left and sets it to 42b. At this time, the third bit from the left of the address map field 41b on the synchronization word transmitted by itself is set.

FIG. 5 is a view for explaining a method of managing a terminal using the address map field, transmitting a synchronization word, and joining a network according to the present invention. First, the power of the DVD 1 is turned on in a state where nothing is participating in the network. The DVD 1 monitors the transmission of the synchronization word from another terminal. However, since there is no transmission of the synchronization word, the DVD 1 obtains the youngest address [0] 51 and transmits the synchronization word 52 as described with reference to FIG. I do. Since there is no terminal other than the DVD1, the next synchronization word becomes empty for new participation, and after the empty, the DVD1 having the youngest address [0] transmits the synchronization word again (FIG. 5A). .

Next, the power supply of the ATV 2 is turned on. AT
V2 monitors the synchronization word, and learns from the address map field of the synchronization word sent from DVD1 that only one terminal has joined the network and its address is [0]. Then, the ATV 2 obtains the address [1] 53, and sends out the synchronization word 54 in the synchronization word part opened for new use, following that the DVD 1 sends out the synchronization word. At this point, DVD 1 knows that a terminal other than itself has joined the network. Since two terminals are participating in the network, ATV2
After the transmission of the synchronization word, the next synchronization word becomes empty. Following the vacancy, DVD1 of [0] in ascending order of address,
ATV2 of [1] sends out a synchronization word (FIG. 5).
(B)).

Subsequently, the power of the GW 3 is turned on. In the same manner as described above, the GW 3 monitors the synchronization word and recognizes that two terminals are participating in the network and the addresses are [0] and [1]. The GW 3 acquires the address [2] 55, sends out the synchronization word 56, and participates in the network (FIG. 5C). Thereafter, participation in the network becomes possible in a similar manner.

FIG. 6 is a diagram for explaining a method of leaving the network according to the present invention. DVD1, ATV2
GW3 participating in the network (FIG. 6)
In (A)), when the ATV 2 normally leaves, the own address [1] in the address map field is turned off at the time of sending out the last synchronization word 61 to leave, and the ATV 2 leaves the network. By monitoring the synchronization word, the DVD1 and GW3 can identify that one terminal has left (FIG. 6B).

On the other hand, there is a case where it is impossible to normally leave the network due to a failure of the terminal or the like. At this time, the GW 3 monitors the content of the synchronization word 62 of the DVD 1 and the absence of the synchronization word from the ATV 2, and the GW 3 monitors the ATV.
2 is detected and the synchronization word 63 is rewritten (FIG. 6)
(C)). As described above, by managing the terminal using the address map field on the synchronization word, it is possible to easily manage the terminal on the network and manage the transmission of the synchronization word.

FIG. 7 illustrates a resource management field indicating a packet use status on a frame according to the present invention. The resource management field exists on the synchronization word similarly to the address map field, and indicates the position of the used packet. Since all the terminals participating in the network monitor the synchronization word, it is possible to know the traffic congestion on the network and available packets by monitoring the resource management field.

In FIG. 7, the terminal monitors the resource management field 71a of the synchronization word, and if there is a vacant resource when transmitting the synchronization word, turns on the resource bit at the vacant position and transmits the synchronization word 71b. Thereafter, the packet is transmitted according to the bit position set by the user. The packet used by itself is held until the next synchronization word is transmitted. When you no longer need to send data,
The resource bit that has been turned on when the synchronization word is transmitted is turned off.

FIG. 8 shows a frame configuration of the present invention. The frame is composed of synchronization words SYC81-83, a data packet 84, and an EOF85. The structure of the synchronization word (SYC) is SOF8 indicating the beginning of the frame.
1, an address map field AMF82 and a resource management field 83. EOF85 indicates the end of the frame. The details of each are as described above.

FIG. 9 shows a wireless communication terminal for realizing the wireless communication method of the present invention. A radio section 91 for transmitting and receiving radio signals, and a radio control section 92 for controlling access to the radio section
And a data processing unit 9 for processing application data
3 and a wireless input / output unit 94.

[0044]

By using the wireless communication method of the present invention,
The communication procedure is simplified compared to the conventional control method,
Efficient media access can be processed in the lower layer close to the radio, efficient use of communication bandwidth,
Wireless control can be performed efficiently.

Further, it is possible to configure a fully distributed terminal independent network, and it is possible to easily perform management even if a plurality of terminals participate in the network without using a complicated protocol. Become. In the present invention, all the terminals operate while monitoring the synchronization word, so that it is easy to join / leave the network. Also, by multiplexing the wireless band with fixed-length packets, it becomes easier to manage resources on the network.

Furthermore, a plurality of fixed-length packets can be used by each terminal, and in addition to two-way communication, asymmetric communication and broadcast communication can be supported.

[Brief description of the drawings]

FIG. 1 is a diagram showing one embodiment of a wireless communication method of the present invention.

FIG. 2 is a diagram showing a transmission order of radio signals and a band to be used according to the present invention.

FIG. 3 is a diagram showing a synchronization management method of the present invention.

FIG. 4 is a diagram showing an address map field of the present invention.

FIG. 5 is a diagram illustrating a method of managing a terminal using an address map field, transmitting a synchronization word, and joining a network according to the present invention.

FIG. 6 is a diagram illustrating a method of leaving a network according to the present invention.

FIG. 7 is a diagram illustrating a resource management field indicating a packet use status on a frame according to the present invention.

FIG. 8 is a diagram showing a frame configuration of the present invention.

FIG. 9 is a diagram showing one embodiment of a wireless communication terminal for realizing the wireless communication method of the present invention.

FIG. 10 is a diagram showing a wireless control method used in a conventional wireless LAN.

[Explanation of symbols]

1 DVD, 2 ATV, 3 GW, 4 ISDN, 5
... TV telephone, 21 ... sync word, 22 ... frame, 23
…packet.

Claims (9)

[Claims] 1. A wireless communication method characterized in that when communicating with a plurality of terminals, the plurality of terminals share a wireless band, and when the terminals communicate, the communication band is shared using a synchronization word. . 2. A wireless unit for transmitting and receiving a wireless signal, a wireless control unit for controlling access to the wireless unit, and application data for communicating with a partner terminal via a wireless signal through the wireless unit and the wireless control unit. A wireless communication terminal comprising a data processing unit for processing the wireless communication terminal, wherein the wireless control unit has a function of performing the wireless communication method according to claim 1. 3. The wireless communication method according to claim 1, wherein when the terminal communicates, the bandwidth is fixed in advance as a unit of band allocation as a packet, and the band used by the terminal is allocated by the number of cells. . 4. The wireless communication method according to claim 1, wherein terminals connected to the network transmit synchronization words in order to ensure synchronization of the entire network. 5. An address map field is provided in the synchronization word, and when each terminal joins / leaves from the network, the terminal determines its own terminal address from the address map field. The wireless communication method as described. 6. A resource map field corresponding to a cell is provided in a synchronization word, and when each terminal communicates, a vacancy of resources is determined from the resource map field to secure a radio band. The wireless communication method as described. 7. The wireless communication method according to claim 4 or 5, wherein after transmitting the synchronization word by the number of terminals participating in the network, one vacancy is provided so as not to transmit the synchronization word. A wireless communication method characterized by enabling new participation in a communication. 8. The wireless communication method according to claim 6, wherein
A wireless communication method comprising transmitting data from a terminal to a network according to the bit content of a resource map field in a synchronization word. 9. A computer-readable storage medium storing a program for causing a computer to implement the method according to claim 7. Description: