Patent Abstract:
In a system for sharing hybrid resources in an independent network, each one of a plurality of stations preferably employs a sharing authority transferring protocol that allows the network control function to be moved from station to station depending on the network traffic. Although a distributed coordination method is normally used in the network, when an individual station determines that a real-time data stream is intended for the station, an apparatus having a method and data format for the use thereof allows control to be transferred to the targeted station. This allows the targeted station to control the sharing of the wireless hybrid resources using a centralized control method in a direct mode for the duration of the real-time service transmission, thereby optimizing network efficiency. As a result of using the distributed control authority of the present invention, a station may be freely subscribe/withdraw to/from the network.

Full Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Notice: More than one reissue application has been filed for the reissue of U.S. Pat. No. 7,453,846. The reissue applications are Reissue Application No. 12/718,087 (the present reissue application), and Continuation Reissue Application Nos. 13/170,786, 13/171,092, 13/171,255, and 13/171,369, all of which are continuation reissue applications of the present reissue application and of U.S. Pat. No. 7,453,846. This reissue application seeks a reissue of U.S. Pat. No. 7,453,846, which issued on Nov. 18, 2008, from application Ser. No. 10/314,295 filed on Dec. 9, 2002, which claims the benefit of Korean Application No. 2001-78664 filed on Dec. 12, 2001. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a wireless independent network based on carrier sense multiplexing access (CSMA)/collision avoidance (CA). More particularly, the present invention relates to a method for sharing hybrid resources in a wireless independent network, a station for the method, and a data format for the method and the station. 
     2. Description of the Related Art 
     Wireless independent networks connect wireless stations without the use of wires in a predetermined area regardless of connections to base networks. For example, home networks connecting information regarding home electronics without the use of wires is a type of wireless independent network. Services in a wireless independent network may generally be classified into a real-time Audio Video (AV) streaming service or a non-real-time AV streaming service. 
     An environment of such a wireless independent network may be characterized as follows. First, since network subscribers&#39; interests concentrate on a real-time AV streaming service in one independent network, it is rare for a large number of real-time AV services to coexist in one independent network. Second, a small number of real-time AV streaming services and a large number of non-real-time AV streaming services can coexist in one independent network. Third, the real-time AV streaming service uses a station that is the subject thereof and limited holding time exists in the service. 
     In the above-described wireless independent network environment, wireless stations (STAs) typically share wireless communications resources. Here, a conventional resource-sharing method may generally be classified into a distributed coordination method or a centralized control method. 
     The distributed coordination method uses a mechanism for minimizing possible message collisions that occur when stations attempt to use a data channel simultaneously. This mechanism is the IEEE 802.11a distributed coordination function (DCF) based on CSMA/CA. In a distributed coordination method using a DCF, random backoff numbers are created to minimize competition-based collisions, the backoff numbers are reduced by stages when a channel is idle for at least a predetermined period of time (in the case of IEEE 802.11, this is referred to as DCF Interframe Space (DIFS)), and data is transmitted when the backoff number becomes “0”. A conventional distributed coordination method for grading priorities of the occupation of resources according to a specific type of data includes a Point Coordination Function (PCF) Interframe Space (PIFS) system and a Short lnterframe Space (SIFS). Priorities of these systems are in the relationship DIFS&gt;PIFS&gt;SIFS, and a station using SIFS has priority over a station using DIFS. However, since a DCF system works on a probabilistic base, it is still possible for stations to collide. 
     In the centralized control method, one control station controls resources shared in a wireless independent network in a bundle. Thus, wireless stations share wireless resources according to the instructions of the control station. The centralized control method may be subdivided into a direct mode and an indirect mode. In the direct mode, a control station controls the time slots for transmission and reception among wireless stations so that the wireless stations directly communicate with one another. The HiperLAN/2 standard is a representative example of the direct mode. In the indirect mode, transmission data of all stations is transmitted to the control station so that the wireless stations indirectly communicate with one another through the control station. This indirect mode is based on the Bluetooth standard. 
     Accordingly, in the above-described distributed coordination method, a specific control station is not required, and a mesh network can be constituted, and a station may easily subscribe to and withdraw from the mesh network. However, the distributed coordination method uses resources ineffectively and cannot support the real-time AV streaming service. In addition, the centralized control method in the indirect mode cannot support the real-time AV streaming service due to the forwarding of packets, which concentrates loading on the control station, and requires the selection of a substitute node when the control station withdraws from the subscribed network. Although the centralized control method in the direct mode uses resources effectively, supports the real-time AV streaming service, and constitutes the mesh network, loading is concentrated on the control station, thus requiring the selection of a substitute node when the control station withdraws from the subscribed network. 
     The aforementioned conventional resource-sharing methods have many problems since they have been developed based on non-real-time services, or due to inflexible structure of networks. 
     SUMMARY OF THE INVENTION 
     In an effort to solve the above-described problems, it is a first feature of an embodiment of the present invention to provide a method for sharing hybrid resources in a wireless independent network that can have the advantages of conventional resource-sharing methods by more efficiently analyzing the environment of the wireless independent network so that wireless resources are shared adaptive to the environment, thereby efficiently supporting real-time services as well as non-real-time services among the wireless stations. 
     It is a second feature of an embodiment of the present invention to provide stations performing the hybrid resources sharing method. 
     It is a third feature of an embodiment of the present invention to provide formats of data transmitted among the stations. 
     Accordingly, a method for sharing wireless hybrid resources among stations in a wireless independent network preferably includes analyzing a received data stream and obtaining network control for optimally transferring that data. An analysis is performed to determine whether currently transmitted data is related to a real-time service when the sharing of the wireless hybrid resources is controlled by a distributed coordination method. A sharing control authority is requested and received by the distributed coordination method, and the sharing of the wireless hybrid resources is controlled by a centralized control method in a direct mode until the real-time service ends if it is determined that the currently transmitted data is related to the real-time service. The sharing control authority corresponds to an authority which controls the sharing of the wireless hybrid resources. If it is determined that the currently transmitted data is not related to the real-time service, the sharing of the wireless hybrid resources may be controlled by the distributed coordination method. 
     Obtaining network control when the currently transmitted data is related to the real-time service preferably includes requesting the sharing control authority by the distributed coordination method if it is determined that the currently transmitted data is related to the real-time service; determining whether the request for the sharing control authority is rejected; controlling the sharing of the wireless hybrid resources with a request for periodic polling, if it is determined that the request is rejected; and then determining whether the sharing of the wireless hybrid resources does not need to be controlled during the real-time service. If it is determined that the sharing of the wireless hybrid resources does not need to be controlled during the real-time service, control is transferred to the aforementioned requesting step. If it is determined the sharing of the wireless hybrid resources still needs to be controlled during the real-time service, control is returned to the step for requesting for periodic polling. 
     If it is determined that the request for the sharing control authority is not rejected, the method preferably additionally includes receiving the sharing control authority and controlling the sharing of the wireless hybrid resources by the centralized control method in the direct mode; determining whether the real-time service ends and returning to the receiving step if it is determined that the real-time service does not end; and returning the sharing control authority if it is determined that the real-time service ends. In the foregoing additional steps, the sharing of the wireless hybrid resources is preferably controlled by the distributed coordination method. 
     A preferred embodiment of a station for performing the wireless hybrid resources sharing method according to the present invention preferably includes a transmission data checking unit and a first controller. The preferred embodiment of the station may further include a second controller. The transmission data checking unit checks whether the currently transmitted data is related to the real-time service and generates a control signal in response to the check result. In response to the control signal, the first controller requests and receives the sharing control authority by the distributed coordination method and controls the sharing of the wireless hybrid resources by the centralized control method in the direct mode until the real-time service ends. Alternately, a second controller may control the sharing of the wireless hybrid resources by the distributed coordination method in response to the control signal. 
     The first controller preferably further includes a request message broadcaster, which broadcasts a control authority requesting message requesting the sharing control authority by the distributed coordination method in response to the control signal and an enable signal; a request rejecting message receiver, which receives a control authority request rejecting message rejecting the request for the sharing control authority and outputs a disable signal in response to the received result; a polling requesting unit, which requests periodic polling in response to the disable signal and the enable signal; a releasing message receiver, which receives a control authority releasing message in response to the control signal and outputs the enable signal in response to the received result; a shared resource controller, which receives the sharing control authority in response to the disable signal and controls the sharing of the wireless hybrid resources by the centralized control method in the direct mode and transmits the sharing control authority releasing message to another station and returns the sharing control authority in response to an ending signal; and a service checking unit, which checks whether the real-time service ends and outputs the checked result as the ending signal. Preferably, a second controller controls the sharing of the wireless hybrid resources by the distributed coordination method in response to the ending signal. 
     To operate the foregoing preferred station using the foregoing preferred method for sharing wireless hybrid resources, a data format preferably includes a control authority requesting message, a control Authority releasing message, and a plurality of transmission frames located therebetween. The control authority requesting message requests the sharing control authority by the distributed coordination method. The control authority releasing message releases the sharing control authority. The plurality of transmission frames are spaced apart from the control authority requesting message and the control authority releasing message, by a PIFS, are also spaced apart from each other by one PIFS, and may have variable lengths. 
     Each one of the plurality of transmission frames preferably further includes a downlink section in which the real-time service-related data is transmitted to another station and which may have a variable length; a polling section in which the other stations related to the real-time service is polled and which has a variable length; and a distribution control section in which non-real-time service-related data is transmitted to another station and which may have a variable length. The downlink section is preferably spaced apart from the polling section by a PIFS. The polling section is preferably spaced apart from the distribution control section by a DIFS. The downlink section preferably includes a plurality of packets which are spaced apart from each other by a PIFS. 
     In the event that a share request rejection message is received in the station, a sharing control authority message may also be received. In such a case, the shared resource controller is preferably idle for a PIFS period, thereby necessitating the inclusion of a PIFS time period between the time of the request for sharing control authority and the receipt of the sharing control authority. Additionally, in the event a sharing rejection message is transmitted by the sharing controller, preferably a SIFS time period is included in the format between the time of transmission of the request and the time of receipt of the rejection message. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other features and advantages of the present invention will become readily apparent to those of ordinary skill in the art by describing in detail preferred embodiments thereof with reference to the attached drawings in which: 
         FIG. 1  illustrates a flowchart of a method for sharing hybrid resources in a wireless independent network according to the present invention; 
         FIG. 2  illustrates a flowchart of a preferred embodiment of step  12  shown in  FIG. 1  according to the present invention; 
         FIG. 3  illustrates a block diagram of a station, according to the present invention, performing the hybrid resources sharing method shown in  FIG. 1 ; 
         FIG. 4  illustrates a block diagram of a preferred embodiment of a first controller shown in  FIG. 3  according to the present invention; 
         FIGS. 5(a) , (b), and (c) illustrate data formats for the above-described hybrid resources sharing method and the station according to the present invention; 
         FIG. 6  illustrates an exploded view of a preferred embodiment of a downlink section shown in  FIG. 5(c) ; and 
         FIGS. 7(a)  and (b) illustrate how the sharing control authority is obtained and how a message rejecting the request for the sharing control authority is received from a control station, respectively, after a message requesting a sharing control authority is broadcasted. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Korean Patent Application No. 2001-78664, filed Dec. 12, 2001, and entitled: “Method for Sharing Hybrid Resources in Wireless Independent Network, Station for the Method, and Data Format for the Method and the Station,” is incorporated by reference herein in its entirety. 
     Hereinafter, a method for sharing hybrid resources in a wireless independent network according to the present invention will be described with reference to the attached drawings. In the drawings, like reference numerals refer to like elements throughout. 
       FIG. 1  illustrates a flowchart of a preferred method for sharing hybrid resources in a wireless independent network according to the present invention. Selection of either a centralized control method in a direct mode or a distributed coordination method is preferably dependent on whether real-time service-related data is transmitted. In step  10 , a determination is made as to whether currently transmitted data is related to a real-time service when the sharing of the wireless resources is controlled based on the above-described distributed coordination method. For example, it may be determined that a real-time AV streaming service is being generated, i.e., the real-time AV streaming service is provided via a wireless independent network. If the currently transmitted data is not related to the real-time service, the distributed coordination method is retained in step  14 . 
     If, however, the currently transmitted data is related to the real-time service when the sharing of the wireless resources is controlled by the distributed coordination method, in step  12 , a station which is the subject of the real-time service (hereinafter referred to as “subject station”) requests a sharing control authority using the distributed coordination method. After the request is admitted sharing control authority is granted to the subject station, and wireless resources are shared under control of the subject station preferably using the centralized control method in a direct mode for the duration of the transmission of the corresponding real-time service. At the completion of the real-time service transmission the subject station restores the sharing of the wireless resources to the distributed coordination method. 
       FIG. 2  illustrates a flowchart of a preferred embodiment of step  12  shown in  FIG. 1  according to the present invention. Step  12  preferably includes steps  20  and  22  for requesting the sharing control authority, steps  24  through  28  for controlling the sharing of wireless resources with a request for periodic polling when the requested sharing control authority is rejected, and steps  30  through  34  for controlling the sharing of the wireless resources by the centralized control method in the direct mode until the real-time service ends when the requested sharing control authority is admitted. 
     After it is determined that the currently transmitted data is related to the real-time service, in step  20  the subject station requests the sharing control authority using the distributed coordination method, e.g., a DCF system. In step  22 , the subject station determines whether the request for sharing control authority has been rejected. In other words, the subject station determines whether a station currently having a sharing control authority (hereinafter referred to as a “control station”) exists by testing for the existence of a “rejection message” from that control station. 
     If it is determined that the request for the sharing control authority is rejected, in step  24  the sharing of the wireless resources is controlled while the subject station requests the control station for periodic polling. For example, if the control station exists, the subject station cannot be granted the sharing control authority, and the control station maintains the sharing control of the wireless resources and a corresponding real-time AV streaming service-related communication is implemented using the existing method. 
     In step  26  the subject station determines whether the real-time service is still being transmitted, i.e., still in progress. If it is determined that the real-time service is still being transmitted, in step  28  the subject station determines whether the sharing of the wireless resources needs to be controlled. In other words, if it has been determined that the real-time service is in process, the subject station monitors whether a control authority releasing message has been received from the control station. 
     If it is determined through the periodic polling that the sharing of the wireless resources does not need to be controlled by the control station for performing the corresponding real-time service-related communication, the process returns to step  20 . In other words, when the subject station does not need to be controlled by the control station any more, it requests the acquisition of the sharing control authority by the distributed coordination method again. However, if it is determined that the subject stations still needs to be controlled by the control station to share the wireless resources when the real-time service is in progress, the process returns to step  24 . 
     Alternatively, if it is determined that the request for the sharing control authority has not been rejected, in step  30  the subject station is granted (i.e., assumes or seizes) the sharing control authority and preferably controls the sharing of the wireless resources by the centralized control method in the direct mode. In step  32 , it is determined whether the real-time service has ended. If it is determined that the real-time service has not ended, the process repeats step  30 , such that the subject station retains the sharing control authority. However, if it is determined that the real-time service has ended, in step  34  the subject station broadcasts a new control authority releasing message to the other stations to return the sharing control authority to the network. When it is determined that the real-time service is not in progress in step  26  or after step  34 , the subject station changes the sharing controls back to the distributed coordination method. 
     A preferred embodiment according to the present invention, showing the structure and operation of stations in an independent network performing the previously described hybrid resources sharing method will be described with reference to  FIGS. 3 and 4 . 
       FIG. 3  illustrates a block diagram of a station for performing the hybrid resources sharing method shown in  FIG. 1 , according to an embodiment of the present invention. The station preferably includes a transmission data checking unit  50 , and a first and a second controller  52  and  54 , respectively. For a better understanding of the present invention, the structure and operation of the station shown in  FIG. 3  will be described assuming that the station is a subject station. 
     The transmission data checking unit  50  checks whether currently transmitted data input via an input port IN 1  is related to a real-time service and outputs a control signal to first and second controllers  52  and  54 , respectively. First and second controllers  52  and  54  generate output control and data signals in response to the check result. 
     If first controller  52  is granted a sharing control authority in response to the control signal input from the transmission data checking unit  50 , the sharing of wireless resources on a central controls system in a direct mode is controlled by first controller  52  using a centralized control method in a direct mode until the real-time service ends. To perform this control function, if it is perceived through the control signal that data input via the input port IN 1  is transmission data for the real-time service, the first controller  52  outputs a signal requesting the sharing control authority to the other stations via an output port OUT 1  and checks whether a message rejecting the request for the sharing control authority is received from another station, e.g., a control station (not shown), via the input port IN 1 . If the first controller  52  is granted the sharing control authority (i.e., not rejected) data input through the input port IN 1  via the transmission data checking unit  50  is transmitted to a corresponding station (not shown) via the output port OUT 1 . 
     The second controller  54  controls the sharing of the wireless resources by the distributed coordination method in response to the control signal input from the transmission data checking unit  50 . Here, the second controller  54  preferably receives data from another station via an input port IN 3  and outputs the data input through the input port IN 1  via the transmission data checking unit  50  to another station via an output port OUT 2 . Here, the second controller  54  may control the sharing of the wireless resources by the distributed coordination method in response to an ending signal generated when the real-time services ends in the first controller  52 . 
       FIG. 4  illustrates a block diagram of a preferred embodiment of the first controller  52  shown in  FIG. 3 . The first controller  52  preferably includes a request message broadcaster  70 , a request rejecting message receiver  72 , a polling requesting unit  74 , a releasing message receiver  76 , a shared resource controller  78 , and a service checking unit  80 . 
     To perform step  20 , in response to the control signal from transmission data checking unit  50  via an input port IN 4  (indicating that received data is related to a real-time service,) service), the request message broadcaster  70  transmits a message requesting control authority to the other stations via an output port OUT 3  using the distributed coordination method. The request message is additionally gated using an enable signal input from the releasing message receiver  76 . If one of the other stations has sharing control authority (i.e., is processing data), that “control station” transmits a rejection message to the subject station. When the control station has completed its data processing activity, it transmits a sharing control authority releasing message using the distributed coordination method. If, however, there is no current active control station, no rejection message will be received. 
     To perform step  22 , the request rejecting message receiver  72  receives any message rejecting the request for the sharing control authority via an input port IN 5  and outputs the received message as a disable signal to the polling requesting unit  74  and the shared resource controller  78 . In response to the disable signal from the request rejecting message receiver  72  and the enable signal input from the releasing message receiver  76 , the polling requesting unit  74 , which performs step  24 , requests the periodic polling from the control station via an output port OUT 4 . In other words, the polling requesting unit  74  requests the periodic polling of the control station whenever a rejection message is received and the sharing control authority releasing message has not yet been received. 
     To perform steps  26  and  28 , in response to the control signal input from the transmission data checking unit  50  via the input port IN 4  (indicating the real-time service) the releasing message receiver  76  monitors the control station for the sharing control authority releasing message via an input port IN 6 . When the sharing control authority releasing message is received, releasing message receiver  76  outputs an enable signal to the request message broadcaster  70  and the polling requesting unit  74 . The releasing message receiver  76  may generate an enable signal having a first logic level if the sharing control authority releasing message is received from the control station and an enable signal having a second logic level if the control authority releasing message is not received from the control station. 
     For the case where no rejection message is received, the shared resource controller  78 , which performs steps  30  and  34 , assumes the sharing control authority in response to the disable signal input from the request rejecting message receiver  72  and thus controls the sharing of the wireless resources using the centralized control method in the direct mode. Here, the shared resource controller  78  may receive data from another station via an input port IN 7  or may output data for the real-time service to another station via an output port OUT 5 . Also, in step  34 , the shared resource controller  78  preferably transmits the sharing control authority releasing message to another station via the output port OUT 5  to return the sharing control authority in response to the ending signal input from the service checking unit and sharing control authority  80 . Although it is not shown as a step in  FIG. 2 , during the time that the subject station has the control authority, the shared resource controller  78  preferably transmits the sharing control rejection messages upon being queried by other stations. 
     The service checking unit  80 , which performs step  32 , checks whether the real-time service has ended and outputs the check result as the ending signal to the shared resource controller  78  and to the second controller  54  via the output port OUT 6 . Here, the second controller  54  controls the sharing of the wireless resources by the distributed coordination method in response to the ending signal input from the service checking unit  80 . 
     Hereinafter, a data format for the hybrid resource-sharing method and the station according to the present invention will be described with reference to the attached drawings. 
       FIGS. 5(a) , (b), and (c) illustrate a timing diagram of a streaming messaging signal having a plurality of partitioning sections according to a preferred data format for the above-described resource-sharing method and station according to the present invention.  FIG. 5(a)  shows sections of the complete data stream and  FIGS. 5(b) and 5(c)  show exploded views of the partitions of a transmission frame. 
     According to the present invention, step  10  of the preferred method shown in  FIG. 1  is performed by during a distributed coordination method during section  90  shown in  FIG. 5(a) . Here, if it is determined that currently transmitted data is related to the real-time service, step  12  is performed during an adaptive control method section  92  shown in  FIG. 5(a) . For this, the subject station obtains the sharing control authority at a starting point  97  of the adaptive control system method section  92 . The length  96  of the adaptive control system method section  92  may vary. When the real-time service ends during step  12 , the subject station returns the sharing control authority at an ending point  98  of the adaptive control system section method  92 . 
     As shown in  FIG. 5(b) , the adaptive control system method section  92  shown in  FIG. 5(a)  preferably includes a control authority requesting message  100 , a series of first through n-th transmission frames  102 ,  104 , . . . and  106 , and a control authority releasing message  108 . The first transmission frame  102  is spaced apart from the control authority requesting message  100  by a Point Coordination Function (PCF) Interframe Space (PIFS)  120  and the n-th transmission frame  106  is spaced apart from the control authority releasing message  108  by a PIFS  126 . The first through n-th transmission frames  102 ,  104 , . . . , and  106  are spaced apart from each other by a PIFS  122  to have priority of the occupation of the resources over DCF-based wireless stations. Here, the first through n-th transmission frames  102 ,  104 , . . . and  106  have lengths  124 , respectively, which may vary depending on characteristics of a corresponding AV streaming service. 
     As shown in  FIG. 5(c) , each one of the first through n-th transmission frames  102 ,  104 , . . . and  106  preferably includes a downlink section  140 , a polling section  142 , and a distribution control section  144 . In the downlink section  140 , real-time service-related transmission data is transmitted to another station and the downlink section  140  has a variable length  160 . In the polling section  142 , which has a variable length  162 , other real-time service-related stations may be polled, and a multiplex polling system may be used for improved performance. In the polling section  142 , a packet is forwarded from the subject station to the control station or another station. 
     In the distribution control section  144 , which has a variable length  164 , non-real-time service-related transmission data is preferably transmitted to another station using a DCF system. If an additional real-time AV streaming service is generated, the message requesting the periodic polling may be transmitted to the control station. Here, the downlink section  140  is spaced apart from the polling section  142  by a PIFS  170 , and the polling section  142  is spaced apart from the distribution control section  144  by a DIFS  172 . 
       FIG. 6  illustrates an exploded view of a preferred embodiment of the downlink section  140  of  FIG. 5(c)  according to the present invention, which preferably includes a plurality of packets  182 ,  184 , . . . and  186 . Referring to  FIG. 6 , the plurality of packets  182 ,  184 , . . . and  186  are spaced apart from each other by a PIFS  180  to maintain the sharing control authority for the downlink section  140 . 
       FIGS. 7(a)  and (b) illustrate views explaining how the sharing control authority is obtained and how the message rejecting the request for the sharing control authority is received from the control station, respectively, after the message requesting the sharing control authority has been transmitted. In  FIG. 7(a) , there is no current active control station, while in  FIG. 7(b) , there is a current an active control station. 
     As shown in  FIG. 7(a) , the request message broadcaster  70  transmits a control authority requesting message  192  via the output port OUT 3 . After the shared resource controller  78  shown in  FIG. 4  is idle for a PIFS  190 , sharing control authority is assumed in section  194 . 
     For the case where an active control station exists, as shown in  FIG. 7(b) , the request message broadcaster  70  broadcasts a control authority requesting message  202 . Then after a SIFS  200  elapses, the request rejecting message receiver  72  shown in  FIG. 4  receives a control authority request rejecting message  204  from the active control station. After a variable time duration  206  during which the active control station completes its control task, a sharing control authority releasing message  208  is transmitted by the active control station, thereby releasing network sharing control authority. 
     At this time the request message broadcaster  70  again transmits a control authority requesting message  192  as in  FIG. 7(a) , and after the shared resource controller  78  is idle for a PIFS  190 , sharing control authority is assumed in section  194 . In an alternate embodiment, the active control station may transmit the sharing control authority releasing message  208  directly to the requesting station, thereby allowing the requesting station to immediately assume sharing control authority in section  194 , and thus avoiding the loss of time periods  190  and  192 . 
     As described above, in a preferred method for sharing hybrid resources in a wireless independent network, a station for the method, and a data format for the method and the station, non-real-time service-related data packets are transmitted/received using a distributed coordination method and real-time service-related data packets are transmitted/received using a centralized control method in a direct mode. In other words, hybrid data is transmitted and received in a wireless independent network. Thus, an efficiency of using resources is maximized, a real-time service of the resources is supported, and a mesh network may be constituted. Further, loading may be prevented from concentrating in a control station and the control station is not fixed. As a result, a station can freely subscribe/withdraw to/from a subscribed network. 
     Preferred embodiments of the present invention have been disclosed herein and, although specific terms are employed, they are used and are to be interpreted in a generic and descriptive sense only and not for purpose of limitation. Accordingly, it will be understood by those of ordinary skill in the art that various changes in form and details may be made without departing from the spirit and scope of the present invention as set forth in the following claims.

Technology Classification (CPC): 7