Patent Document

BACKGROUND INFORMATION  
         [0001]    An IEEE 802.11a protocol is a new specification that represents the next generation of Wireless Local Area Networks (“WLANs”). The IEEE 802.11a protocol uses 300 MHz of bandwidth allocated by the Federal Communications Commission (“FCC”) for what is called Unlicenced National Information Infrastructure (“UNII”). A WLAN implementing the 802.11a protocol can transmit at rates up to 54 Mbps.  
           [0002]    The 300 MHz of bandwidth is divided into three 100 MHz bands, each one having different regulatory limitations. The first or lower band (“UNII-1”) (i.e., from 5.15-5.25 Gigahertz (“GHz”)), may transmit at a maximum power of 50 milliwatts (“mW”) and only use an antenna that is “captive” (i.e., internal or fixed) to a transmission unit (e.g., a mobile unit (“MU”) or access point (“AP”)). The second or middle band (“UNII-2”) (i.e., from 5.25-5.35 GHz) may transmit at a maximum power of 250 mW. The third or upper band (“UNII-3”) (i.e., from 5.725-5.825 Ghz) and use the internal or external antenna, may transmit at a maximum power of 1 W. Each of the lower and middle bands (i.e., UNII-1 and UNII-2) has four operating channels. These regulatory specifications have been determined by the FCC and the use and limitations of the bandwidth may vary from country to country.  
           [0003]    When installing the WLAN several APs may be necessary to optimally cover a desired area. Each AP is assigned a specific channel to communicate with MUs so that there is no interference with the other APs communications. If more than four channels are necessary to prevent an interference (e.g., eight APs are needed to cover an area and all the APs must use different channels), then the WLAN must use UNII-1 as well as UNII-2 channels. Due to the “captive” antenna regulatory requirements for UNII-1, a different AP which uses UNII-2 channels must be used. This sacrifices the versatility of purchasing a single AP product that can be used for all wireless networking needs.  
           [0004]    Alternatively, only AP units with “captive” antennas may be used for all channels. Such AP units sacrifice improved coverage that may be achieved when using UNII-1 and UNII-2 channels with external antennas. Therefore, there is a need for APs that can comply with the FCC regulation of “captive” antennas for UNII-1 channels with the flexibility of using external antennas for UNII-2 channels. Similarly, there is a need for APs that have the flexibility to comply with the varying regulations of different countries for the UNII-1 and UNII-2 bands.  
         SUMMARY OF THE INVENTION  
         [0005]    The present invention relates to is a method and system which includes an arrangement including an internal wireless communication antenna and a wireless communication device couplable (e.g., an 802.11a access point) to one of an external wireless communication antenna and the arrangement. The external antenna may have a longer range than the internal antenna.  
           [0006]    When the arrangement is attached to the device, the device is capable of unitizing either first or second wireless channels. When the arrangement is not attached to the device, the device utilizes only the second channel.  
           [0007]    The device may include a switch activated when the arrangement is attached to the device and at least one antenna connector. The external antenna may be coupled to the device using the at least one antenna connector. In addition, the arrangement may include at least one further connector and it may be coupled to the device using the at least one connector and the at least one further connector. 
       
    
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0008]    [0008]FIG. 1 shows an exemplary embodiment of an access point according to the present invention;  
         [0009]    [0009]FIG. 2 a  shows an exemplary embodiment of an internal accessory antenna arrangement according to the present invention;  
         [0010]    [0010]FIG. 2 b  shows an exemplary embodiment of the access point with the internal accessory antenna arrangement attached according to the present invention; and  
         [0011]    [0011]FIG. 3 shows an exemplary method according to the present invention. 
     
    
     DETAILED DESCRIPTION  
       [0012]    [0012]FIG. 1 shows an exemplary embodiment of an access point (“AP”)  10  according to the present invention. The AP  10  may contain a plurality of antenna connectors  12  and  14 . Each of the antenna connectors  12 - 14  may be connected to cables  36  and  38  that are attached to a conventional external antenna (not shown). Internally, the AP  10  may contain a computing arrangement that runs a channel assignment program as well as other programs.  
         [0013]    In addition, the AP  10  may include a micro-switch  16  that may be located proximal to one or both of the antenna connections  12 - 14 . The micro-switch  16  may be placed, for example, inside the AP  10  with only a small entry hole making it accessible. This prevents the micro-switch  16  from being inadvertently activated (i.e., closed). In the configuration illustrated in FIG. 1, the micro-switch  16  is open indicating to the AP  10  that the external antennas are being used. The AP  10  allows only use of the UNII-2 channels when the micro-switch  16  is open in order to comply with the FCC regulations.  
         [0014]    [0014]FIG. 2 a  shows an exemplary embodiment of an internal accessory antenna arrangement (“IAAA”)  20  according to the present invention. The IAAA  20  may contain a plurality of captive antennas  22 - 24 . The captive antennas  22 - 24  may be connected to internal cables  26 - 28  that are attached to internal antenna connectors  32 - 34 . The IAAA  20  may also contain an appurtenance  30 , which may be, for example, a plastic extrusion or a metal lead, adapted to fit in the entry hole and close the micro-switch  16 .  
         [0015]    The internal antenna connectors  32 - 34  are adapted to connect to the antenna connectors  12 - 14  (e.g., they may be the same type of connectors (e.g., SMA connectors), but of the opposite gender). The internal antenna connectors  32 - 34  are aligned on the IAAA  20  allowing the internal connectors  32 - 34  to attach to the antenna connectors  12 - 14 . The appurtenance  30  is aligned on the IAAA  20  so that it closes the micro-switch  16  when the IAAA  20  is attached to the AP  10 .  
         [0016]    [0016]FIG. 2 b  shows an exemplary embodiment of the IAAA  20  mounted on the AP  10  according to the present invention. In this configuration, the IAAA  20  becomes part of the base unit mechanically and completely encapsulates the antenna connectors  12 - 14 . The attachment of the IAAA  20  may be analogized, for example, to the attachment of a battery to a cell phone. Generally, the cell phone battery is external to the cell phone; however, when attached the battery becomes an integral part of the cell phone shape, as well as its function.  
         [0017]    In the configuration illustrated in FIG. 2 b,  the micro-switch  16  is depressed indicating to the AP  10  that the IAAA  20  is being used. The AP  10 , therefore, allows the use of the UNII-1 channels, as well as the UNII-2 channels for channel assignments. The AP  10  is in compliance with the FCC regulation, because the IAAA  20  acts as a “captive” antenna, allowing use of the UNII-1 channels only when the IAAA  20  is attached.  
         [0018]    [0018]FIG. 3 shows a method according to the exemplary embodiment of the present invention. The method is described with reference to FIGS. 1, 2 a  and  2   b.  Those skilled in the art will understand that other systems having varying configurations may be used to implement the exemplary method.  
         [0019]    One manner of initiating the exemplary method is activation of a channel assignment program (Step  200 ). The channel assignment program may be used when setting up or changing the WLAN configuration. When doing so, a channel is assigned to the AP  10  so that it neither interferes with other APs nor do other APs interfere with it. In order to ensure compliance with the FCC regulation, the exemplary method performs a check of the channel assignment. When the channel assignment program is initiated it first runs the exemplary method to determine which channels are available from a regulatory perspective.  
         [0020]    Another manner of initiating the method is a detection of a change in the status of the micro-switch  16  (i.e., closed to open or open to closed.) When such a change occurs, the IAAA  20  has either been attached or removed from the AP  10 . If a UNII-1 channel has been assigned to the AP  10 , it either ceases or resumes transmitting based on the outcome of the method.  
         [0021]    In step  205 , the AP  10  determines whether the IAAA  20  is attached. This is determined by checking the state (i.e., open or closed) of the micro-switch  16 . If the micro-switch  16  is closed, then the IAAA  20  is attached as shown in FIG. 2 b , and the method continues with step  210 .  
         [0022]    In step  210 , the AP  10  allows to utilize any UNII-1 and UNII-2 channels. If the method was initiated by the channel assignment program, then the user is given an option to assign an appropriate channel. If the method was initiated by the changing state of the micro-switch  16 , then the AP  10  resumes transmission if it had been assigned the channel.  
         [0023]    In step  215 , if it had been determined in Step  205  that the IAAA  20  is not attached as shown in FIG. 1, the AP  10  does not allow transmission using the UNII-1 channels. Thus, the AP  10  allows transmission using only the UNII-2 channels. If the method was initiated by the channel assignment program, then the user is not giv8en the option of assigning a UNII-1 channel. If the method was initiated by the changing state of the micro-switch  16 , then the AP  10  ceases transmission if it had been assigned a UNII-1 channel.  
         [0024]    The above exemplary method allows the AP  10  to comply with the FCC regulations. At the same time, the AP  10  retains the capability of using external, and possibly higher gain, antennas when using the UNII-2 channels. This provides customers who require use of all eight channels, a single product that can satisfy their needs.  
         [0025]    In an alternative exemplary method the same embodiment may be used to comply with the varying regulations in other countries. A configuration software package may accompany the AP  10  to allow a user to configure it. When initially configuring the AP  10 , the configuration software preset with the country&#39;s particular limitations, downloads the information to the AP  10 . The values for power for the different bands, as well as the exact specifications for what would be allowed in step  210  and disallowed in step  215  would be modified. This provides customers who need to install WLANs worldwide, a single product that can satisfy their needs.  
         [0026]    The present invention has been described with reference to an embodiment with the AP  10  implementing the IEEE 802.11a protocol, having dual external antenna connectors, as well as other specific characteristics. One skilled in the art would understand, though, that the present invention may also be successfully implemented, for example, with a different protocol that required a similar “captive” antenna limitation or instead of the AP  10  with a mobile unit. Accordingly, various modifications and changes may be made to the embodiments without departing from the broadest spirit and scope of the present invention as set forth in the claims that follow.

Technology Category: 5