CN100426772C - Wireless terminal apparatus for automatically changing wlan standard and method thereof - Google Patents

Abstract

The invention provides a wireless terminal device and a method thereof with the function of automatically changing the standard of a wireless local area network (WLAN). The wireless terminal device includes a memory for storing condition change information, a wireless communication module for communicating with a predetermined corresponding node according to the first WLAN standard, and a communication state detection unit for detecting the communication state of the wireless communication module and determining whether an event satisfying the change condition occurs. , and a central processing unit for changing the first WLAN standard to the second WLAN standard and establishing a communication link. Therefore, an optimized WLAN standard can be established, and communication can be performed according to the WLAN standard.

Description

Wireless terminal equipment and method for automatically changing wireless local area network standard

technical field

The invention relates to a wireless terminal device and a method for performing wireless network communication functions. More specifically, the present invention relates to a wireless terminal device and method thereof, which support a plurality of Wireless Local Area Network (WLAN) standards (the WLAN standards are hereby incorporated by reference), select the most suitable standard for the current communication environment, and The selected standard to perform wireless network communication functions.

Background technique

A high-speed wireless network that establishes a network environment by using waves or light instead of cables has been increasingly used in many fields. Since a wireless network does not require cables to distribute work, it can facilitate the establishment of a network. Also, since it operates on broadband radio waves (2.4GHz, 5GHz), it is possible to transmit data at a high rate of 11Mbps to 54Mbps. Methods for establishing a wireless network include an ad hoc method used in transferring data between laptop computers only through a wireless LAN card, and an infrastructure method using an access point (AP) to connect a wired network. ).

FIG. 1A shows a wireless network system employing a specific method for communication. As shown in FIG. 1A, each wireless node such as a PC 11, a laptop computer 12, and a multifunction peripheral 13 communicates directly with another wireless node without going through an additional central management device.

FIG. 1B shows a wireless network system employing an infrastructure approach for communication. Referring to FIG. 1B , the wired infrastructure in which respective nodes 21 , 22 , 23 such as PCs and servers are connected one to another via wires also includes an access point (AP) 20 . AP 20 is a device that connects wireless nodes such as laptops, PCs, multifunction peripherals to a wired infrastructure. Furthermore, the various wireless nodes 30, 40 communicate with each other indirectly through the AP.

According to various WLAN standards, communication is performed between respective wireless nodes of an ad hoc method, and communication is performed between an AP of an infrastructure method and each wireless node. WLAN standards (the entire contents of which are hereby incorporated by reference) are mainly classified into the IEEE802.11 standard used in the United States, the Super LAN standard used in Europe, and the MMAC-PC standard used in Japan. Among these standards, the IEEE 802.11 standard is popular in the United States and Asia, and the standard is classified into 802.11, 802.11a, 802.11b, and 802.11g.

A user of a terminal device supporting a wireless network function sets a predetermined communication profile to perform communication according to a predetermined WLAN standard. A communication profile includes service set identification (SSID), mode of operation, channel type, and security information. The terminal device selects one of the above-mentioned WLAN standards for communication according to the set profile.

If the wireless terminal device supports both the ad hoc method and the infrastructure method, the user selects the mode of operation and selectively adopts both standards. However, although the mode of operation has been changed, the traditional wireless terminal equipment still maintains the current WLAN standard. In this case, if the wireless terminal device is placed in an environment where various APs coexist to support different WLAN standards or a single AP exists to support different WLAN standards, frequency interference will be generated between WLAN standards. As a result, noise is generated and communication conditions are deteriorated. Also, radio frequency resources are not used efficiently.

Also, a change occurs in a network environment due to a newly set communication profile, but a conventional wireless terminal device also maintains the current WLAN standard, so it cannot operate smoothly. Even if the wireless terminal equipment is designed to support different WLAN standards, the user must directly find the current communication standard and update the profile.

Contents of the invention

The present invention has been developed to solve the above-mentioned problems. Accordingly, an aspect of the present invention is to provide a wireless terminal device and method thereof, which change a wireless local area network (LAN) standard according to surrounding network conditions when a communication mode changes, thereby preventing interference with another wireless terminal device.

Another aspect of the present invention is to provide a wireless terminal device and method thereof capable of automatically selecting a wireless local area network (WLAN) standard most suitable for a current communication state, thereby allowing a user to establish an optimized communication environment.

To achieve the above aspects according to an exemplary embodiment of the present invention, a wireless terminal device is provided. The wireless terminal equipment includes: a wireless communication module, which establishes a communication link with a corresponding node in one of the special mode and the infrastructure mode as operation modes, and communicates with the corresponding node; and a central processing unit, which controls the wireless The communication module, so that if the operation mode of the wireless communication mode is changed during the wireless communication, the first WLAN standard used before the mode change is changed to the second WLAN standard, and the communication link is established according to the second WLAN standard, wherein the first WLAN standard The second WLAN standard is different from the first WLAN standard and the second WLAN standard uses a frequency band different from that of the first WLAN standard.

According to an exemplary embodiment of the present invention, the central processing unit finds a standard from a plurality of WLAN standards using a frequency band different from that of the first WLAN standard, and uses the found standard as the second WLAN standard.

According to an exemplary embodiment of the present invention, the wireless terminal device further includes a key input receiving unit which inputs a mode selection signal to select one of the specialized mode and the infrastructure mode.

According to an exemplary embodiment of the present invention, the wireless terminal device further includes: an output unit that displays a user interface window through which communication profile information on a plurality of WLAN standards is input; and a memory that stores information input through the user interface window Communication profile information.

According to an exemplary embodiment of the present invention, if the mode selection signal selects a certain operation mode, the central processing unit determines the WLAN standard used in the network within the communication range of the wireless communication module, and uses the determined WLAN standard A different standard is used as the second WLAN standard.

According to an example embodiment of the present invention, there is provided a method of communicating with a corresponding node in a predetermined mode of operation. The method includes the steps of: determining whether the mode of operation has changed; if the mode of operation has changed during wireless communication, determining a first WLAN standard used before the mode of operation was changed; and using a second WLAN standard different from the first WLAN standard, establishing a communication link according to a second WLAN standard using a frequency band different from that of the first WLAN standard; and communicating, wherein the operating modes include an ad hoc mode and an infrastructure mode.

According to an example embodiment, the using step further includes finding a standard from a plurality of WLAN standards using a frequency band different from the first WLAN standard frequency band, and using the found standard as the second WLAN standard.

According to example embodiments, the method further includes the steps of displaying a user interface window to input communication profile information on a plurality of WLAN standards, and storing the communication profile input through the user interface window.

According to an example embodiment, the step of using further includes retrieving communication profile information on a second WLAN standard; and establishing a communication link according to the second WLAN based on the retrieved communication profile.

According to an exemplary embodiment, the method further includes the steps of: receiving a mode selection signal for selecting one of the infrastructure mode and the specialized mode; determining a WLAN standard used in a network existing within the communicable range of the wireless terminal device; and using the determined The WLAN standard is a different standard as the second WLAN standard.

According to an exemplary embodiment of the present invention, there is provided a wireless terminal device for communicating with a corresponding node in a predetermined operation mode in a wireless communication system, the wireless terminal device comprising: a memory storing communications of a plurality of WLAN standards Profile information and condition change information; the wireless communication module communicates with a predetermined corresponding node according to the first WLAN standard; and a communication state detection unit detects the communication state of the wireless communication module and determines whether an event meeting the change condition occurs . If the communication state detection unit determines that such an event has occurred during wireless communication, the wireless communication module changes the first WLAN standard to a second WLAN standard and performs communication according to the second WLAN standard, wherein the second WLAN standard is the same as the first WLAN standard. The WLAN standards are different and the second WLAN standard uses a frequency band different from that of the first WLAN standard.

According to an example embodiment, the wireless terminal device further includes an input unit for inputting communication profile information and change condition information.

According to an example embodiment, the wireless terminal device further includes a central processing unit that searches a plurality of WLAN standards for a second WLAN standard, retrieves a communication profile of the found second WLAN standard from memory, and The standard controls the wireless communication module to communicate based on the retrieved communication profile.

According to an exemplary embodiment, if the communication link off (LINK OFF) condition is selected as the change condition, the central processing unit searches for a communicable second WLAN standard from a plurality of WLAN standards when the communication LINK OFF (link off) condition is satisfied.

According to an example embodiment, if a low transmission rate is selected as the change condition and the low transmission rate is less than a reference rate, the central processing unit searches for a second WLAN standard among a plurality of WLAN standards supporting a transmission rate greater than the reference rate.

According to an example embodiment, if the time change condition is selected as the change condition and the time is changed, the central processing unit changes the first WLAN standard to the second WLAN designated for the current time according to the information on the WLAN standards respectively assigned to different times standard.

According to an example embodiment, the wireless terminal device further includes an output device displaying a user interface window for setting information of the communication profile and information of the change condition.

According to an exemplary embodiment of the present invention, a communication method in a wireless terminal device is provided. The method includes the steps of: performing wireless communication with a predetermined corresponding node according to a first WLAN standard; detecting the state of the wireless communication and determining whether an event satisfying a predetermined change condition occurs; if such an event occurs during the wireless communication, The first WLAN standard is changed to a predetermined second WLAN standard and wireless communication is performed according to the second WLAN standard, wherein the second WLAN standard is different from the first WLAN standard and the second WLAN standard uses the same WLAN standard as the first WLAN standard. different frequency bands.

According to an example embodiment, the changing step includes retrieving a communication profile for the second WLAN standard, and performing wireless communication according to the second WLAN standard based on the retrieved communication profile information.

According to an example embodiment, the method further includes the step of receiving and storing communication profile information and condition change information for a plurality of WLAN standards.

According to example embodiments, the information of the communication profile includes at least one of service set identification (SSID), WLAN standard information, operation mode information, authentication information, and encryption information.

According to an example embodiment, the changed reference may be determined as one of a link down condition, a low transmission rate condition, and a time variation condition.

Description of drawings

The above aspects and other advantages of the invention will become apparent by describing example embodiments of the invention with reference to the accompanying drawings, in which:

FIG. 1A shows a conventional structure of a wireless network environment according to an ad hoc approach;

FIG. 1B shows the structure of a wireless network environment according to an infrastructure approach;

Figure 2 shows a block diagram of a wireless terminal device according to an exemplary embodiment of the present invention;

FIG. 3 shows a user interface window for determining a communication profile of a wireless terminal device according to an exemplary embodiment of the present invention;

FIG. 4 shows a flowchart of a wireless communication method according to an exemplary embodiment of the present invention;

Fig. 5 shows a flowchart of a wireless communication method according to an exemplary embodiment of the present invention;

Figure 6 shows a block diagram of a wireless terminal device according to an example embodiment of the present invention;

FIG. 7 shows an example implementation of a communication profile for a predetermined wireless local area network (WLAN) standard according to an example embodiment of the present invention;

Figure 8 shows an example embodiment of a user interface window that determines the WLAN standard automatic change function of the wireless end device of Figure 6; and

Fig. 9 shows a flowchart of a wireless communication method for a wireless terminal device according to an exemplary embodiment of the present invention.

Throughout the drawings, like reference numerals will be understood to indicate like parts, assemblies and structures.

Detailed ways

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

Fig. 2 shows a block diagram of a wireless terminal device according to an exemplary embodiment of the present invention. Referring to FIG. 2 , a wireless terminal device according to an exemplary embodiment of the present invention includes an input unit 110 , a central processing unit 120 , a wireless communication module 130 , a memory 140 , and an output unit 150 .

The wireless communication module 130 communicates with corresponding nodes according to predetermined wireless local area network (WLAN) standards. For this, the wireless communication module 130 includes a wireless network card (not shown). The wireless communication module 130 communicates in an ad hoc mode or an infrastructure mode according to user's selection. In the infrastructure mode, the wireless communication module 130 establishes communication links with neighboring access points (APs) for communication. If multiple APs supporting different WLAN standards are provided, at least two APs cooperate with each other to communicate with the wireless communication module 130 .

The input unit 110 receives various selection signals from a user. A user inputs a mode selection signal using various button keys provided on a body of the wireless terminal device to select one of the dedicated mode and the infrastructure mode. The button keys include number keys, direction keys, and an enter key. The input unit 110 transmits a mode selection signal to the central processing unit 120 .

When an operation mode is selected through the input unit 110, the wireless communication module 130 performs communication according to various kinds of WLAN standards in the selected operation mode. In WLAN standards, IEEE 802 11b, 802 11g and 802 11a are commonly used. IEEE 802.11b has a maximum data rate of 11 Mbps and operates on the 2.4GHz frequency band. IEEE 802.11g is an improvement of IEEE 802.11b, and has a maximum data rate of 54Mbps and operates on the 2.4GHz frequency band. IEEE 802.11a is an extended version of the existing WLAN standard, and has a data rate of 54 Mbps or more and operates on the 5GHz frequency band. Since IEEE 802.11b and IEEE 802.11g have the same frequency band of 2.4GHz, they are compatible with each other. Therefore, if the wireless communication module 130 communicates according to IEEE 802.11b but the surrounding environment communicates according to IEEE 802.11g, interference will occur between them.

In order to prevent interference, the following processing is performed. When a mode selection signal for changing an operation mode is received through the input unit 110, the central processing unit 120 searches for a standard having a frequency band different from that of the first WLAN standard used in the proximity environment. If a second WLAN standard is found, the communication profile for the second WLAN standard is retrieved from memory 140 . The wireless communication module 130 establishes a communication link with a corresponding node according to the second WLAN standard based on the retrieved communication profile. Corresponding nodes may include wireless terminal devices such as laptops, personal computers (PCs), personal digital assistants (PDAs) and network printers in ad hoc mode, or they may be access points in infrastructure mode.

Communication profile information about a plurality of WLAN standards used by the wireless communication module 130 is previously input by the user and stored in the memory 140 . The communication profile information includes at least one of service set identification (SSID), WLAN standard information, operation mode information, authentication information and encryption information. The output unit 150 displays a user interface window for a user to input communication profile information.

FIG. 3 shows an example of a user interface window 300 for setting a communication profile. In FIG. 3 , the SSID includes an ID assigned to distinguish the current wireless terminal device from the corresponding node. Authentication information and encryption information are used to maintain security in communication with the corresponding node.

The operation mode information selects one of an infrastructure mode and an ad hoc mode. In Infrastructure mode, select the WLAN standard appropriate to the desired connection access point. And it is possible to select the WLAN standard for the ad hoc mode.

In this case, the WLAN standard for the current mode of operation is automatically selected by referring to WLAN standards in different modes of operation. That is, if 'Auto-Setting' is selected to set the WLAN standard for the ad hoc mode, as shown in FIG. 3 , an optimal WLAN standard is automatically set by referring to the WLAN standard for infrastructure or surrounding network conditions. In this case, select the menu "Remove infrastructure" to remove the WLAN standard in infrastructure mode, or select the menu "Remove adjacent network" to remove the WLAN standard used in the adjacent network.

For example, assume that communication is performed according to IEEE 802.11a in the infrastructure mode. If the operation mode is changed to ad hoc mode and the menu "Remove infrastructure" is selected, WLAN standards other than standard IEEE802.11a are looked for to use in ad hoc mode. It is better to use standards of different frequency bands. In the example above, the standard IEEE 802.11g or 802.11b uses a different frequency band of 2.4GHz than IEEE 802.11a's 5GHz.

If the menu "Remove Neighboring Networks" is selected, WLAN standards used in a network environment located within a communicable range are considered, and a WLAN standard having a different frequency band is selected. In the above example, communication with the first access point is performed according to the IEEE 802.11a standard in infrastructure mode. Then, if you switch the operation mode to ad hoc mode, the IEEE 802.11b or 802.11g standard is selected.

Unlike the above case where there are multiple access points, if there are surrounding terminals communicating with one another in ad hoc mode, the WLAN standards of the surrounding terminals are considered and a different WLAN standard is selected.

Meanwhile, if the operation is switched from the ad hoc mode to the infrastructure mode, the WLAN standard can be automatically set. That is, if the menu 'Auto-Set' is selected for the WLAN standard of the infrastructure mode, the WLAN standard is automatically set with reference to the WLAN standard used between surrounding wireless terminal devices or the WLAN standard supported by another access point.

Fig. 4 shows a flowchart of a wireless communication method according to an exemplary embodiment of the present invention. Referring to FIG. 4, in step S410, a user inputs communication profile information about a plurality of WLAN standards through a user interface window. The input communication profile information is stored in memory 140 .

If it is determined in step S420 that the operation mode is switched, then in step S430 it is determined whether the "auto-setting" function of automatically setting the WLAN standard is selected. Then, if the 'Auto-Setting' function is selected, the kind of the first WLAN standard used before the mode change is determined and a second WLAN standard different from the first WLAN standard is searched for in step S440. A second WLAN standard is found from a plurality of WLAN standards included in the communication profile information input through the user interface window. Preferably, the second WLAN standard uses a frequency band different from that of the first WLAN standard.

In step S450, a communication link with a corresponding node is established according to the found second WLAN standard.

Meanwhile, if there is no change in the operation mode in step S420, or if there is a change in the operation mode but the WLAN standard automatic setting function is not selected in step S430, the current WLAN standard is still used in step S460.

Fig. 4 shows the case of switching the operation mode to different other modes. However, when the wireless terminal device attempts initial communication, the WLAN standard can be selected with reference to the WLAN standard for different operation modes.

Fig. 5 shows a flowchart of a wireless communication method according to an exemplary embodiment of the present invention. Referring to FIG. 5, communication profile information on a plurality of WLAN standards is set in step S510. If a predetermined operation mode is selected at step S520, it is determined at step S530 whether the menu "Auto-Setting" is selected.

If the menu 'Auto-Setting' is selected, the WLAN standard used in the surrounding network existing within the communicable range is determined at step S540. Then, in step S550, a WLAN standard different from the type of the determined WLAN standard is searched for, and in step S560, a communication link is established according to the found WLAN standard.

If the menu "Auto-Setting" is not selected, then in step S570 a communication link is established according to the WLAN standard set as default.

The embodiment explained in Fig. 5 can be applied in case of a change of operation mode. That is, if the operation mode is changed, surrounding network conditions are considered and a WLAN standard for the changed operation mode is determined.

Fig. 6 shows a block diagram of a wireless terminal device according to an example embodiment of the present invention. Referring to FIG. 6 , a wireless terminal device according to an exemplary embodiment of the present invention includes an input unit 210 , a central processing unit 220 , a wireless communication module 230 , a communication state detection unit 240 , a memory 250 , and an output unit 260 .

The input unit 210 inputs various types of selection signals from the user and transmits the signals to the central processing unit 220 . The user inputs information on communication profiles of various WLAN standards used by the wireless communication module 230 or information on changing conditions through the input unit 210 .

The wireless communication module 230 performs communication in an infrastructure mode or an ad hoc mode according to IEEE 802.11b, 802.11g, 802.11a standards. According to the corresponding WLAN standard, the wireless communication module 230 may have an additional network card, or may have an integrated card supporting all 802.11a, IEEE 802.11b, and 802.11g standards.

In order for the wireless communication module 230 to select a certain standard from the WLAN standards, the user must set a predetermined communication profile. The central processing unit 220 controls the output unit 260 to display an image for setting a communication profile.

FIG. 7 shows an example of a communication profile setting image 400 displayed through the output unit 260. Referring to FIG. Referring to FIG. 7, the communication profile includes a service set identification (SSID), WLAN standard information, operation mode information, authentication information, and encryption information. SSID refers to the ID that allows the wireless network card to communicate with the AP or another node. The WLAN standard information is used to specify one of the WLAN standards that the wireless communication module 230 can support. A user selects a WLAN standard based on the characteristics of each standard. In addition, the user can select one of operation modes such as an ad hoc mode or an infrastructure mode, and determine authentication information and encryption information for security.

As shown in FIG. 7 , if the user determines a communication profile according to a specific WLAN standard, the central processing unit 220 stores the corresponding determined profile in the memory 250 .

The central processing unit 220 displays a user interface window through the output unit 260 to determine whether to set the WLAN standard automatic change function.

FIG. 8 shows an example of a user interface window displayed through the output unit 260. Referring to FIG. Referring to FIG. 8, a user interface window 500 shows ON/OFF (on/off) of a WLAN standard automatic change function, change conditions, profiles according to corresponding standards. If the WLAN standard automatic change function (ON) is selected, the change condition must be set. In this case, the change condition includes at least one of LINK OFF, low transfer rate, and time change.

The communication state determination unit 240 detects the current communication state and determines whether an event satisfying the changed setting condition occurs. More specifically, it is determined whether the current link is disconnected, whether the transmission rate is less than a reference rate, or whether a time change is determined.

If the communication status detection unit 240 determines that an event satisfying the change condition occurs, the central processing unit 220 searches for a different supportable WLAN standard. If there is a suitable WLAN standard, the central processing unit 220 retrieves a communication profile for the found WLAN standard, and controls the wireless communication module 230 to establish a link according to the found WLAN standard according to the retrieved communication profile.

Next, the operation of the wireless terminal device according to the exemplary embodiment of the present invention will be described in detail.

If LINK OFF is selected as the change condition, the communication state detection unit 240 determines whether the current communication link is in an off state. If the currently linked AP is lost or if the current communication link is disconnected due to a change of encryption key information, it is determined that an event satisfying the change condition has occurred. And, if no data packet is sent from the corresponding node during the predetermined time, or if no acknowledgment packet is received in response to the data packet sent from the wireless terminal device, it is determined that the change condition is satisfied (in other words, LINK OFF condition) event. If it is determined that LINK OFF has occurred, the communication state detection unit 240 notifies the central processing unit 220.

The central processing unit 220 searches for a second WLAN standard by using various communication profiles stored in the memory 250 to test different WLAN standards. Alternatively, after the communication link is established according to the corresponding WLAN standard, the central processing unit 220 searches for the second WLAN standard according to whether a confirmation data packet is received in response to the sent test data packet.

If a low transmission rate is selected as a change condition, a predetermined reference time is set to compare with the transmission rate. If the reference rate is set to 12 Mbps, the communication state detection unit 240 determines that an event satisfying the change condition occurs when the current transmission rate is less than 12 Mbps. Then, the central processing unit 220 searches for a WLAN standard from among a plurality of WLAN standards capable of maintaining a rate of 12 Mbps or higher. If an 802.11g standard with a data rate of 52Mbps or higher is found, a communication link is established according to the 802.11g profile.

If the time change condition is selected as the change condition, the user must pre-allocate the appropriate WLAN standard to each time. For example, use the 802.11b standard assignment for 0 o'clock to 8 o'clock, the 802.11a standard assignment for 8 o'clock to 17 o'clock, and the 802.11g standard assignment for 17 o'clock to 0 o'clock. When the current time shows 08:01, the communication state detection unit 240 determines that an event satisfying the change condition has occurred. Therefore, the central processing unit 220 establishes the communication link according to the profiles assigned to the 802.11a standard from 8 o'clock to 17 o'clock.

Fig. 9 shows a flowchart of a wireless communication method according to an exemplary embodiment of the present invention. Referring to FIG. 9, if a function of WLAN standard automatic change is selected (ON) at step S910, it is determined at step S920 whether an event satisfying a change condition occurs. Since the kinds of change conditions and the occurrence of events were described above, their descriptions are omitted.

If it is determined that the event has occurred, the user searches for a second WLAN standard that does not meet the change condition at step S930. If there is a second WLAN standard at step S940, a profile for the second WLAN standard is retrieved from the memory 250 at step S950 and used to establish a communication link. Since detailed descriptions about the communication profiles are given above with reference to FIG. 7, they are omitted here.

If there is no second WLAN standard, the previous WLAN is maintained at step S960.

The wireless communication method described above can be applied to any device supporting the WLAN function, such as a laptop computer, a PC, a network printer, or a network multifunction peripheral. According to exemplary embodiments of the present invention, since an appropriate WLAN standard can be selected for a current communication environment and communicated, a stable communication environment can be established.

According to an exemplary embodiment of the present invention, when the operation mode is changed, it is possible to prevent interference with surrounding networks by the current WLAN standard used before changing the mode to a different standard. If the infrastructure mode is changed to the ad-hoc mode, communication is performed according to a WLAN standard using a frequency band different from that of previous WLAN standards supported by the access point, thereby preventing interference and enabling efficient use of radio frequency resources. Moreover, according to the exemplary embodiments of the present invention described above, in a network where multiple WLAN standards coexist, if an event occurs that satisfies a preset change condition, the current WLAN standard is automatically changed to a different WLAN standard. Since an appropriate WLAN standard can be selected, the communication status can be maintained stably. Also, since the user is not required to set a profile anytime the WLAN standard changes, the user can feel more convenient. A wireless terminal device according to an exemplary embodiment of the present invention may be a laptop computer, a PC, a printer, and a multifunction peripheral device having a wireless network function.

The above-described example embodiments and advantages are exemplary only and should not be construed as limiting the scope of the invention. The description of the embodiments of the present invention is illustrative and does not limit the scope of the claims. Many alternatives, changes, and variations will be apparent to those skilled in the art.

Claims (23)

1. A wireless terminal device, comprising: a wireless communication module, which establishes a communication link with a corresponding node in at least one of an ad hoc mode and an infrastructure mode as operation modes according to the first wireless local area network WLAN standard, and performs communication with the corresponding node; and a central processing unit, which controls the wireless communication module; Wherein, if the operation mode of the wireless communication mode is changed during wireless communication, the first WLAN standard is changed to a second WLAN standard, and a communication link is established according to the second WLAN standard, wherein the second WLAN standard is identical to the first WLAN standard different and the second WLAN standard uses a frequency band different from that of the first WLAN standard. 2. The wireless terminal device according to claim 1, wherein the central processing unit finds the second WLAN standard from a plurality of WLAN standards. 3. The wireless terminal device according to claim 2, further comprising a key input receiving unit which inputs a mode selection signal to select at least one of the dedicated mode and the infrastructure mode. 4. The wireless terminal device according to claim 3, further comprising: an output unit that displays a user interface window including input of communication profile information about a plurality of WLAN standards; and A memory stores communication profile information entered through the user interface window. 5. The wireless terminal device according to claim 3, wherein, if the mode selection signal selects a mode, the central processing unit determines a WLAN standard used in a network within a communicable range of the wireless communication module, and A standard different from the determined WLAN standard is used as the second WLAN standard. 6. A method of communicating with a corresponding node in a predetermined mode of operation in a wireless terminal device, the method comprising: determining whether the mode of operation has changed; If the mode of operation is changed during the wireless communication, determining the first WLAN standard used before the mode of operation was changed; and using a second WLAN standard different from the first WLAN standard, establishing a communication link according to the second WLAN standard, and using a frequency band different from that of the first WLAN standard; and to communicate, Wherein the operation mode includes ad hoc mode and infrastructure mode. 7. The wireless communication method according to claim 6, wherein said using step comprises: Search for a second WLAN standard from among multiple WLAN standards. 8. The wireless communication method according to claim 7, further comprising: displaying a user interface window to enter communication profile information for a plurality of WLAN standards; and Communication profile information entered through the user interface window is stored. 9. The wireless communication method according to claim 8, wherein said using step further comprises: retrieving communication profile information for the second WLAN standard; and A communication link is established according to a second WLAN standard based on the retrieved communication profile. 10. The wireless communication method according to claim 6, further comprising: receiving a mode selection signal selecting at least one of the infrastructure mode and the specialized mode; determine the WLAN standard used within the network existing within the communicable range of the wireless terminal device; and A standard different from the determined WLAN standard is used as the second WLAN standard. 11. A wireless terminal device, comprising: A memory for storing information including communication profiles of a plurality of wireless local area network WLAN standards and information about condition changes; The wireless communication module communicates with the corresponding node according to the first WLAN standard; and The communication state detection unit detects the communication state of the wireless communication module and determines whether an event satisfying the change condition occurs, Wherein, if the communication state detection unit determines that the event satisfying the change condition occurs during the wireless communication, the wireless communication module changes the first WLAN standard to the second WLAN standard and performs communication according to the second WLAN standard, wherein the first WLAN standard The second WLAN standard is different from the first WLAN standard and the second WLAN standard uses a frequency band different from that of the first WLAN standard. 12. The apparatus according to claim 11, further comprising an input unit for inputting the communication profile information and the change condition information. 13. The device of claim 12, further comprising a central processing unit that searches a plurality of WLAN standards for a second WLAN standard, retrieves a communication profile for the second WLAN standard from memory, and based on the second WLAN standard The retrieved communication profile is used to control the communication module to communicate. 14. The device according to claim 13, wherein if the LINK OFF condition of the communication link is selected as the change condition, the central processing unit, when the condition of the communication LINK OFF—that is, the link is closed—is satisfied, from a plurality of WLANs Look for the second WLAN standard in the standard. 15. The apparatus according to claim 13, wherein if a low transmission rate is selected as the change condition and the low transmission rate is smaller than a reference rate, the central processing unit finds the first WLAN standard among a plurality of WLAN standards supporting a transmission rate greater than the reference rate. Two WLAN standards. 16. The apparatus according to claim 13, wherein if the time change condition is selected as the change condition and the time is changed, the central processing unit changes the first WLAN standard to the second WLAN standard according to information on WLAN standards respectively assigned to different times. Two WLAN standards, wherein the second WLAN standard is specified for the current time. 17. The apparatus according to claim 13, further comprising an output unit displaying a user interface window for at least one of setting information of the communication profile and information of the change condition. 18. The device according to claim 17, wherein the information of the communication profile includes at least one of SSID, WLAN standard information, operation mode information, authentication information and encryption information. 19. A wireless communication method, comprising: performing wireless communication with the corresponding node according to the first wireless local area network WLAN standard; detecting the state of the wireless communication and determining whether an event has occurred that satisfies a predetermined change condition; and If said event occurs during wireless communication, changing the first WLAN standard to a second WLAN standard; and wireless communication according to the second WLAN standard, Wherein the second WLAN standard is different from the first WLAN standard and the second WLAN standard uses a frequency band different from that of the first WLAN standard. 20. The method of claim 19, wherein said changing step comprises: A communication profile for a second WLAN standard is retrieved from among the plurality of WLAN standards. 21. The method of claim 20, further comprising receiving and storing communication profile information for a plurality of WLAN standards and information about the event. 22. The method according to claim 21, wherein the information of the communication profile includes at least one of SSID, WLAN standard information, operation mode information, authentication information and encryption information. 23. The method of claim 21, wherein the event includes at least one of a link down, a low transmission rate, and a time-varying condition.

Images