JP2005080164A - Wireless communication system, wireless communication apparatus, and wireless communication method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce power consumption and to speed up transmission/reception of data by eliminating advance negotiation in wireless communication. <P>SOLUTION: The wireless communication apparatus STAn for making wireless data communication with other communication terminal starts wireless data communication with a particular communication terminal by using a predetermined particular communication address and employing a predetermined communication parameter without carrying out advance negotiation. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a communication technique for a plurality of communication terminals to perform wireless data communication.

  In recent years, electronic devices having a wireless communication function are becoming popular. Among them, in particular, portable electronic devices that are equipped with a wireless communication function are increasing for convenience in that data communication can be performed anywhere regardless of the place of use.

  In wireless data communication, the wireless LAN system (IEEE 802.11), which is being standardized by the Institute of Electrical and Electrics Engineers (IEEE), is the most powerful protocol.

  In IEEE 802.11, it is stipulated that negotiation of communication partner search, authentication, adjustment of communication parameters, etc. is performed before starting data communication. When a certain communication terminal performs wireless communication with another communication terminal. In this way, a state in which wireless communication is possible with each other is established by performing the negotiation as described above.

  FIG. 5 is a diagram illustrating a processing procedure of wireless communication conventionally performed based on a standard such as IEEE 802.11. First, the communication terminal STA1 sends a search request for searching for another communication terminal to be a communication partner in the wireless communication area. The communication terminal STA2 that has received this search request returns a search response to the communication terminal STA1. Next, the communication terminal STA1 that has received the search response transmits an authentication request for performing data communication. The communication terminal STA2 that has received the authentication request returns an authentication response according to the authentication result of the communication terminal STA1. Next, the communication terminal STA1 whose connection is permitted by the authentication response transmits a connection request to the communication terminal STA2. In response to the connection request, the communication terminal STA2 returns various information such as communication parameters and terminal identification information in the connection response.

  By performing the negotiation as described above, communication parameters are adapted in the communication terminals STA1 and STA2 on the transmission side and the reception side, and wireless communication in an optimal state is established. Thereafter, data transmission / reception between the communication terminal STA1 and the communication terminal STA2 is started.

  The prior negotiation as described above is performed when a certain communication terminal performs wireless communication with an unspecified communication terminal under a system configuration for general-purpose wireless communication. Is important in the sense of establishing

  However, in a wireless communication system, when communication partners are fixed to specific communication terminals and data is transmitted and received between the specific communication terminals, communication parameters can be fixed in advance. This eliminates the need for such negotiation.

  In general, many portable communication terminals are driven by, for example, a built-in battery. In such a portable communication terminal, when data is transmitted / received to / from a specific communication terminal, negotiation in advance consumes power of the built-in battery, and the effective operation time of the portable communication terminal There was a problem that became shorter.

  Furthermore, if negotiation is performed in advance, it takes a certain time until data transmission to another communication terminal is started, and thus there is a problem that data cannot be transmitted and received quickly.

  Therefore, the present invention has been made to solve the above-described problems, and provides a communication technology that can reduce power consumption by omitting prior negotiation and can quickly transmit and receive data. , For that purpose.

  A wireless communication apparatus according to the present invention performs wireless data communication with another communication terminal, and is not subjected to negotiation in advance with a specific communication terminal, and has a predetermined specific communication address. And applying predetermined communication parameters to start wireless data communication.

  The wireless communication system according to the present invention is configured such that a plurality of communication terminals perform data communication wirelessly, and when the plurality of communication terminals perform data communication with each other, each communication terminal performs negotiation in advance. Rather, using a predetermined specific communication address and applying a predetermined communication parameter, wireless data communication with another communication terminal is started.

  The specific communication address is preferably set in advance by executing an application program.

  The wireless communication method according to the present invention is a method for performing wireless data communication with other communication terminals, and is determined in advance without performing negotiations with a specific communication terminal in advance. Wireless data communication is started using a specific communication address and applying predetermined communication parameters.

  According to the present invention, power consumption can be reduced by omitting the negotiation process, and data transmission / reception can be started quickly.

  In particular, a specific communication address is preset by execution of an application program, so that a different wireless network can be formed for each application program, and data can be quickly shared or exchanged between the same application programs. Can do.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows a schematic diagram of a wireless network. In this wireless network, a wireless LAN basic unit called BSS (Basic Service Set) is formed by four communication terminals (wireless communication apparatuses) STA1 to STA4, and the wireless communication system 100 is configured. However, the configuration of the wireless network shown in FIG. 1 is merely an example, and in the present invention, the number of communication terminals configuring the wireless network is not limited to four.

  FIG. 2 is a functional block diagram of the communication terminals STA1 to STA4, and shows functional blocks common to the communication terminals STA1 to STA4. Therefore, in the following description, when a function common to the communication terminals STA1 to STA4 is described, the communication terminal STAn will be referred to. The communication terminal STAn includes a CPU 1, a ROM 2, a RAM 3, a wireless module 4, and an antenna 5. The CPU 1 is an arithmetic processing unit that performs overall control of the communication terminal STAn. The CPU 1 executes various arithmetic processes by reading and executing a program stored in the ROM 2 or the RAM 3 and via the wireless module 4 and the antenna 5. It exchanges data with other communication terminals.

  The wireless module 4 includes a MAC module 41, a BBP module 42, and an RF module 43. The wireless module 4 can perform a general wireless data communication by executing a communication procedure based on the IEEE802.11 standard. As an operation, it is configured such that wireless data communication can be performed without prior negotiation with a specific communication terminal. That is, the wireless module 4 can perform wireless communication in either the general-purpose communication mode based on the IEEE 802.11 standard or the specific communication mode in which wireless data transmission is performed with a specific communication terminal. It has become. Whether the wireless module 4 performs general wireless data communication (general communication mode) or wireless data communication (specific communication mode) with a specific communication terminal is defined in a program executed by the CPU 1. Yes. Therefore, the wireless module 4 executes the communication mode selected by the CPU 1.

  The MAC module 41 performs an access control operation corresponding to a MAC (Media Access Control) layer in the hierarchical structure of data communication, and is unique to the present invention in addition to a function of executing a communication procedure based on the IEEE 802.11 standard. It has a function to execute the communication procedure. The BBP module 42 has a function of executing baseband processing. The RF module 43 receives the baseband signal from the BBP module 42 and outputs the data on a predetermined band of radio waves to the antenna 5, while extracting the data from the radio waves received by the antenna 5 and outputs the baseband signal to the BBP module 42. The function to pass to.

  When the general-purpose communication mode is executed in the communication terminal STAn and wireless data communication based on IEEE 802.11 is performed, data communication is started after negotiation with other terminal devices in advance. In the negotiation, the MAC module 41 notifies the other party of the address (MAC address) assigned to its own MAC module 41, and when transmitting / receiving data after the negotiation, the MAC module 41 sends the data addressed to its own MAC address. Receive.

  Next, a case where the specific communication mode is executed in the communication terminal STAn and wireless data communication with the specific communication terminal is performed will be described. The specific communication terminal is, for example, a communication terminal in which the same application program is executed as the application program executed in the communication terminal STAn. When data is shared between these same application programs, each communication terminal STAn executes wireless data communication processing with a specific communication terminal, which is wireless data communication unique to the present invention.

  FIG. 3 is a flowchart showing a processing sequence executed in the communication terminal STAn in the specific communication mode, and particularly shows a processing procedure related to wireless data communication. First, the CPU 1 of the communication terminal STAn reads and executes an application program from the ROM 2 or RAM 3 (step S1). The CPU 1 reads out communication parameters defined in the application program being executed, and sets the communication parameters for the wireless module 4 (step S2). As a result, various communication conditions in the wireless data communication are set to specified values by the program. That is, communication parameters such as a beacon interval and a communication speed necessary for wireless communication, which are conventionally adjusted by a prior negotiation process, are set as values defined in the program in step S2.

  Further, the CPU 1 reads an address defined in the application program being executed, and sets the address for the wireless module 4 (step S3). The address set in step S3 is an address that can be identified by other communication terminals, and is a specific communication address. For this reason, the MAC module 41 performs data transmission / reception to other communication terminals based on the specific communication address set in step S3.

  Thereafter, data transmission / reception between the communication terminal STAn and another communication terminal is started (step S4), and wireless data communication is continued as necessary until the application program ends (Yes in step S5).

  Details of the wireless data communication will be described. When data to be transmitted to another communication terminal is transferred from the CPU 1 that executes the application program to the wireless module 4, the wireless module 4 transmits data to the specific communication address set in advance in step S3. For example, when the same program is executed in another communication terminal, the same address (specific communication address) is set in the other communication terminal, and the other communication terminal When data with a specific communication address is received, it is recognized that it is addressed to itself and is taken in. Such a reception operation is the same in the communication terminal STAn that has performed data transmission. When data having the same address as the specific communication address set in step S3 is received via an antenna, communication is performed. The terminal STAn takes in the data and passes it to the CPU 1.

  That is, the communication terminal STAn is configured to immediately start data transmission / reception using an address that can be identified by a specific communication terminal without performing negotiation with another communication terminal in advance in the specific communication mode. .

  As a result, a communication form as shown in FIG. 4 is realized. However, FIG. 4 illustrates a case where data communication is performed between the communication terminals STA1 and STA2. In the specific communication mode, unlike the general-purpose communication mode, the negotiation process with other communication terminals is omitted. Therefore, as shown in FIG. 4, data transmission / reception starts immediately when communication is required. It will be. As a result, power consumption for communication processing for negotiation is suppressed, and the effective operation time of the communication terminal STAn can be extended. In addition, since data transmission / reception is started immediately, data transmission / reception can be performed quickly.

  As described above, the communication terminal STAn configuring the wireless network can perform wireless communication in the general-purpose communication mode and the specific communication mode, and when the specific communication mode is performed, the specific communication mode To start wireless data communication by using a predetermined specific address (specific communication address) and applying a predetermined communication parameter without performing negotiation with the terminal in advance. Composed. Therefore, the negotiation process before the start of data transmission / reception can be omitted, and the power consumption can be reduced. In addition, since the time required for negotiation is omitted, data can be transmitted and received quickly.

  Such a communication terminal STAn is configured to receive data with its own unique address and data with a specific communication address. In the general-purpose communication mode, the communication terminal STAn is assigned with its own unique address. The received data can be received, and in the specific communication mode, the data with the specific communication address can be received.

  Further, the communication terminal STAn can selectively execute one of the general-purpose communication mode and the specific communication mode, and a communication mode executed by an application program executed in the communication terminal STAn is defined. Therefore, when efficient data transmission / reception is required for executing the application program, a specific communication mode may be defined for the program, and wireless data communication corresponding to the program is realized.

  The specific communication address set in the specific communication mode is set in advance by executing an application program in the communication terminal STAn. Therefore, if data is transmitted / received using the specific communication address, the specific communication address is set. Data can be exchanged with the terminal, and there is no need to negotiate in advance. In particular, since a specific communication address is set by executing an application program, a different wireless network can be formed for each application program, and reception of data that cannot be processed by its own terminal (program) can be prevented. It is possible to effectively share or exchange data among other application programs.

  As mentioned above, although embodiment which is an example of this invention was described, this invention is not limited to the thing of the content mentioned above.

  For example, in the above, the case where the communication terminal STAn is capable of operating one of the general-purpose communication mode and the specific communication mode characteristic of the present invention has been illustrated. It may be one that performs wireless data communication with a communication terminal.

  In the above description, the specific communication address is defined in the application program. However, the present invention is not limited to this. For example, when a specific communication address is stored in advance in the memory or the like of the MAC module 41, and the MAC module 41 operates in the specific communication mode and starts transmission / reception of data without performing negotiation in advance, it is related to the program. Instead, data transmission / reception may be started using a specific communication address stored in advance in the MAC module 41.

  In the above description, since the specific communication address serves as an identifier for data transmission / reception, the wireless module 4 must always be in an awake state (operating state), thereby draining the power of the built-in battery. In order to prevent this, for example, in the first data exchange immediately after starting data transmission / reception, an identification ID is assigned to each communication terminal STA1 to STA4 included in the wireless network, and the master communication terminal serving as a master station is assigned. After determining one, IEEE 802.11 PCF (Point Coordination Function) communication may be performed thereafter.

  PCF communication is a communication mode based on so-called master control, in which a beacon frame is transmitted from a master communication terminal at regular intervals (beacon intervals), and each communication terminal STA1 to STA4 performs data transmission and reception during the beacon interval. It is. Each communication terminal STA1 to STA4 can identify whether data addressed to itself is included during the beacon interval by referring to a TIM (Traffic Indication Map) included in the beacon frame. Therefore, at the start of data transmission / reception processing, each communication terminal STA1 to STA4 can grasp whether or not the data addressed to itself is included in each beacon interval by shifting to the PCF communication mode. In this case, the doze state (sleep state) can be set in the beacon interval, and as a result, power consumption can be reduced.

  As described above, the wireless communication terminal according to the present invention can be used in various fields such as industrial use, public use, and entertainment use. For example, it can be used when communication terminals used in an industrial system share or exchange data with each other. Alternatively, it can also be used when reflecting the latest information on a communication terminal owned by the user in a public facility. Further, in a portable game machine equipped with a wireless function, it is also effective when data is shared or exchanged between game machines possessed by a plurality of players. This is also effective when digital data with a wireless function is used to share or exchange image data among the digital cameras.

1 shows a schematic diagram of a wireless network. It is a functional block diagram of a communication terminal. It is a flowchart which shows the process sequence performed in a communication terminal at the time of specific communication mode. It is a figure which shows the process sequence of the radio | wireless communication in embodiment of this invention. It is a figure which shows the process sequence of the conventional radio | wireless communication.

Explanation of symbols

1 CPU
2 ROM
3 RAM
4 wireless module 41 MAC module 100 wireless communication system STAn (STA1 to STA4) communication terminal (wireless communication apparatus)

Claims (5)

A wireless communication device that performs wireless data communication with other communication terminals,
The wireless data communication is started by using a predetermined specific communication address and applying a predetermined communication parameter without performing negotiation in advance with a specific communication terminal. Wireless communication device. The wireless communication device according to claim 1,
The specific communication address is set in advance by executing an application program. A wireless communication system configured such that a plurality of communication terminals perform wireless data communication,
When a plurality of communication terminals perform data communication with each other, each communication terminal uses a predetermined specific communication address and performs a predetermined communication parameter without performing negotiation in advance. A wireless communication system characterized by starting wireless data communication with a communication terminal. The wireless communication system according to claim 3,
The specific communication address is preset by executing an application program in each communication terminal. A method for performing wireless data communication with other communication terminals,
The wireless data communication is started by using a predetermined specific communication address and applying a predetermined communication parameter without performing negotiation in advance with a specific communication terminal. Wireless communication method.

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