Patent Publication Number: US-2007097898-A1

Title: Automatic switching system expanding the service range of an access point and method for the same

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      This invention relates to an automatic switching system expanding the service range of an AP and method for the same and particularly to an automatic switching system that expands the service range of an AP through a WLAN card and method for the same.  
      2. Description of Related Art  
      It forms a WLAN (Wireless Local Area Network) that a computer connects to an access point (AP) through a wireless LAN card for implementing wireless local networking, thereby accessing network resources. In the structure of WLAN, an AP must be installed at a node of the WLAN and a WLAN card must be provided in client equipment, such as a computer, so that wireless Internet access may be achieved through the AP and the WLAN card.  
      The service of current AP to the client equipment is in a range of only hundreds of meters; as shown in  FIG. 1 , in the service range  81  of AP, all the sets of client equipment, such as computers  71 ,  72 , and  73  may connect with each other through the WLAN card (not shown) and the AP  70 , while far from the service range  81  of AP  70 , the sets of client equipment as a computer  74  and a PDA  75  cannot connect with each other through the WLAN card and the AP  70 . Further, it is subject to shields, such as walls or windows, and thus the range of service of the AP  70  to the computers may be reduced to tens of meters.  
      In order to expand the service range of AP, currently, installation of dense APs or repeaters may be implemented, as shown in  FIG. 2  for installation of the wireless LAN repeater  76  in the WLAN. The repeater  76  may expand the service range  81  of AP  70  into a service range  82 , making the computer  74  and the PDA  75  communicate with the AP  70  wirelessly.  
      Regardless of the dense APs or repeaters installed to expand the service range of AP, the prime cost of APs, repeaters, and layout significantly increases and the loading of manpower maintenance is heavy. Thus, to build a wider WLAN, decrease the cost, and lower the load of maintenance are tasks to be dealt with.  
     SUMMARY OF THE INVENTION  
      Technical tasks to be dealt with according to this invention lies in a switching system that expands the service range of an AP and method for the same, by using a WLAN card left unused to automatically switch to the function of a repeater, for expanding the service range of AP.  
      In order to solve the technical problem, according to an embodiment of this invention, the switching system expanding the service range of an AP, which operates on an information processing platform provided with a WLAN card, comprising a detect module that is used to determine whether the platform executes an application program providing a network service. A software module is provided with a suite of software for the repeater and a suite of software for the WLAN card. According to the results given from the detect module, a switching module switches the WLAN card to use the repeater software or the WLAN card software. Accordingly, when the detect module determines that the information processing platform is executing the application program that provides the network service, the switching module switches the WLAN card to use the WLAN card software, and when the detect module determines the platform does not execute the application program that provides the network service, the switching module switches the WLAN card to use the repeater software, making the card automatically switches to the repeater.  
      In order to solve the technical problem, according to another embodiment of this invention, a method of automatic switching to expand the service range of AP is provided, which operates on an information processing platform provided with a WLAN card, in which the platform is in the service range of AP, comprising providing the WLAN card software and the WLAN repeater software for the WLAN card to use; determining whether the information processing platform is executing an application program providing the network service; switching a suite of software used by the card to the WLAN card software, when the detection result is correct, so that the WLAN card may be used to connect with the AP; switching the suite of software used by the card to the WLAN repeater software, when the detection result is not correct, so that the WLAN card may be used to expand the service range of AP.  
      The switching system that expands the service range of AP and method for the same according to this invention is used to expand the service range of AP, thereby large amounts of APs and WLAN repeaters being unnecessary and then making it possible to reduce the cost of WLAN layout. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a schematic view illustrating the service range of a conventional access point (AP);  
       FIG. 2  is a schematic view illustrating the expansion of service range of the conventional AP by means of a WLAN repeater;  
       FIG. 3  is a view of a system structure of one of the preferred embodiments of this invention;  
       FIG. 4  is a flow chart of one of the preferred embodiments of this invention; and  
       FIG. 5  is a schematic view illustrating the expansion of service range of the AP according to this invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
      This invention provides an automatic switching system that expands the service range of an access point (AP) and method for the same. An AP, a WLAN card, and a WLAN repeater in a hardware structure are formed mainly with a media access controller (MAC), a base band controller, and a RF module (controller); however, the services provided are different from each other in that suits of software used are different; namely, by means of different software, the AP may serve as a WLAN card or the WLAN card may also serve as a WLAN repeater. In this invention, by means of different software, the WLAN card may be switched to or from the WLAN repeater to function. Thus, when the WLAN card is in the range of service of the AP, the service range of the AP may be expanded when the WLAN card switches to the WLAN repeater to function.  
      Refer now to  FIG. 3  for a system structure of one of the preferred embodiments of this invention. In the embodiment, an information processing platform  10  is provided with a WLAN card  17  and may connect with an AP  20  through the WLAN card  17 , in which the platform  10  may be a computer, a PDA, or a set of equivalent equipment. On the platform  10 , the software is upgraded to provide the WLAN card  17  an automatic switching system, making the card  17  may automatically switch to or from the WLAN repeater depending on a practical operating condition.  
      In this embodiment, the automatic switching system comprises a detect module  11 , a switching module  13 , and a software module  15 , in which the detect module  11  functions to determine whether an operating system  19  in the information processing platform  10  is executing the application program providing network service, in which the application program may be web browser software, e-mailing software, or another software required for the WLAN card; a WLAN card  17  left unused may be found according to a result given from the module  11 . Depending on a result given by the detect module  11 , the switching module  13  switches the software used by the WLAN card  17 . The software used by the WLAN card  17  is provided by the software module  15  and may be a suite of WLAN repeater software  151  or a suite of WLAN card software  153 . When the WLAN card  17  uses the WLAN repeater software  151 , the card  17  executes the function of repeater, while when the card  17  uses the WLAN card software  153 , the card  17  executes the function of card.  
      In the embodiment, the software used by the card  17  that is left unused, namely, not operated by a user to wirelessly access to Internet, is used to switch the card  17  to the repeater for expansion of service range of AP  20 , when the user want to wirelessly access to Internet through the card  17 , the software used by the WLAN card  17  is switched to the function of the WLAN card. Thus, when the detect module  11  determines that the information processing platform  10  is executing the application program that provides the network service, the switching module  13  switches the WLAN card  17  to the WLAN card software  153 . When the detect module  11  determines that the information processing platform  10  does not execute the application program that provides the network service, the switching module  13  switches the WLAN card  17  to the WLAN repeater software  151 . To sum up, in the embodiment, the software used by the WLAN card  17  may switches automatically so that the WLAN card  17  may automatically switch to or from the WLAN repeater to function.  
      Refer now to  FIG. 4  for a flow chart of one of the preferred embodiments of this invention. When being booted, the platform  10  scans the AP (S 401 ) surrounding through the WLAN card  17 , in which the card  17  as defaulted uses the WLAN card software  153 ; then, it determines whether the card  17  may connect to the AP  20  (step S 403 ); if the result is No, go back to step S 401 ; if the result is Yes, it indicates that the WLAN card  17  is in the service range of AP  20 , further check if the platform  10  is executing an application program (S 405 ); according to step S 405 , check if the card  17  is left unused (S 407 ), in which at the step, the detect module  11  may determine whether the platform  10  is executing an application program that provides a network service and “the WLAN card  17  left unused” means that no connection to any AP  20  for wireless access to Internet; namely, the platform  10  does not execute the application program that provides the network service.  
      If the result is No at step S 407 , go back to step S 405  to continue. If the result is Yes at step S 407 , reset the WLAN card  17  and the switching module  13  automatically switches to reload the WLAN repeater software  151  for the WLAN card  17  to use (S 409 ), then the WLAN card  17  switches to the WLAN repeater to function. Next, go on to check if a user starts a new application program (S 411 ); according to step S 411 , further determine whether the application program needs a network service (S 413 ), and at this step the detect module  11  may determine the information processing platform  10  is executing the application program that provides the network service; if the result is No, go back to step S 411  to continue, while if the result is Yes, reset the WLAN card  17  and the switching module  13  automatically switches to reload the WLAN card software  153  for the WLAN card  17  to use (S 415 ); at this time, the WLAN card  17  is switched back to the function of the WLAN card, and go back to step S 405  to continue.  
      In a flow chart of the embodiment of  FIG. 4 , when the WLAN card  17  is left unused, the switching module  13  may automatically switch the software used by the card  17  to the WLAN repeater software  151  from the WLAN card software  153  so that the card  17  switches to the WLAN repeater to function, thereby the service range of AP  20  being expanded. When the card  17  switches to the WLAN repeater to function, as long as the platform  10  starts to execute the application program that provides the network service, the switching module  13  still may automatically switch the WLAN repeater software  151  currently used by the WLAN card  17  to the WLAN card software  153 , making the WLAN card  17  switches back.  
      Additionally, when using the WLAN card software  153 , in order to prevent the card  17  from being temporarily left unused, the WLAN card  17  is switched to the WLAN repeater to function, which may be solved by determining whether the card  17  is left unused for more than a specified time. If the card  17  is left unused for more than a specified time, the detect module  11  is used to determine whether the platform executes the application program providing the network service in order to switch the card  17  to the WLAN repeater to function.  
      Refer now to  FIG. 5  for illustration of the expansion of service range of the AP according to this invention. The computers  21 ,  22 , and  23  are in the range  31  of service that the AP  20  may provide, while the computer  24  and the PDA  25  are far from the range  31  of service that the AP  20  may provide. The computers  21 ,  22 , and  23  are provided with the automatic switching system used in the embodiment to expand the service range of AP. In  FIG. 5 , the WLAN card (not shown) used by the computer  21  is left unused and automatically switched to the WLAN repeater to function. Thus, the service range  31  of AP  20  may be expanded into the service range  32  so that the computer  24  and the PDA  25  may connect with the AP  20 .  
      To sum up, the automatic switching system that expands the service range of an access point and method for the same according to this invention is featured with: 
          1. expansion of the service range of AP by means of the WLAN card left unused in the condition of no increase of APs or WLAN repeaters. making it possible to reduce the cost of WLAN layout and the load of manpower maintenance.     2. a function to make the WLAN card automatically switch to or from the WLAN repeater without manpower aid.        

      However, in the description mentioned above, only the preferred embodiments according to this invention are provided without limit to this invention and the characteristics of this invention; all those skilled in the art without exception should include the equivalent changes and modifications as falling within the true scope and spirit of the present invention.