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

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.

Description

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 IN1 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 OUT1 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 IN1. If the first controller 52 is granted the sharing control authority (i.e., not rejected) data input through the input port IN1 via the transmission data checking unit 50 is transmitted to a corresponding station (not shown) via the output port OUT1.

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 IN3 and outputs the data input through the input port IN1 via the transmission data checking unit 50 to another station via an output port OUT2. 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 IN4 (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 OUT3 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 IN5 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 OUT4. 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 IN4 (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 IN6. 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 IN7 or may output data for the real-time service to another station via an output port OUT5. Also, in step 34, the shared resource controller 78 preferably transmits the sharing control authority releasing message to another station via the output port OUT5 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 OUT6. 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 method section 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 OUT3. 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.

Claims

1. A method for sharing wireless hybrid resources among stations in a wireless independent network, the method comprising:

(a) determining 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;

(b) requesting and receiving a sharing control authority by the distributed coordination method, and controlling the sharing of the wireless hybrid resources 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,

wherein the sharing control authority corresponds to an authority which controls the sharing of the wireless hybrid resources.

2. The method as claimed in claim 1, further comprising (c) controlling the sharing of the wireless hybrid resources by the distributed coordination method if it is determined that the currently transmitted data is not related to the real-time service.

3. The method as claimed in claim 1, wherein (b) comprises:

(b1) 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;

(b2) determining whether the request for the sharing control authority is rejected;

(b3) controlling the sharing of the wireless hybrid resources with a request for periodic polling, if it is determined that the request is rejected;

(b4) determining whether the sharing of the wireless hybrid resources does not need to be controlled during the real-time service, going back to step (b1) if it is determined that the sharing of the wireless hybrid resources does not need to be controlled during the real-time service, and going back to step (b3) if it is determined the sharing of the wireless hybrid resources still needs to be controlled during the real-time service;

(b5) receiving the sharing control authority and controlling the sharing of the wireless hybrid resources by the centralized control method in the direct mode if it is determined that the request for the sharing control system is not rejected;

(b6) determining whether the real-time service ends and going back to step (b5) if it is determined that the real-time service does not end; and

(b7) returning the sharing control authority if it is determined that the real-time service ends,

wherein the sharing of the wireless hybrid resources is controlled by the distributed coordination method.

4. The method as claimed in claim 1, wherein:

(a) further comprises identifying a station subject to the real-time service as a subject station; and

(b) comprises requesting and receiving the sharing control authority by the subject station in accordance with the distributed coordination method, and controlling the sharing of the wireless hybrid resources by the subject station in accordance with the centralized control method in the direct mode until the real-time service ends if it is determined that the currently transmitted data is related to the real-time service.

5. The method as claimed in claim 4, wherein the subject station receives the sharing control authority when no other station in the wireless independent network has the sharing control authority.

6. A station for performing the wireless hybrid resources sharing using a method for sharing wireless hybrid resources among stations in a wireless independent network, the station comprising:

a transmission data checking unit configured to check whether currently transmitted data is related to a real-time service and to generate a control signal in response to the check result; and

a first controller configured to request and receive a sharing control authority by a distributed coordination method and to control sharing of the wireless hybrid resources by a centralized control method in the direct mode until the real-time service ends, in response to the control signal.

7. The station as claimed in claim 6, further comprising a second controller which controls the sharing of the wireless hybrid resources by the distributed coordination method in response to the control signal.

8. The station as claimed in claim 6, wherein the first controller comprises:

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,

wherein a second controller controls the sharing of the wireless hybrid resources by the distributed coordination method in response to the ending signal.

9. The data format as claimed in claim 8, wherein after the request message broadcaster broadcasts the sharing control authority requesting message, the shared resource controller is idle for a PIFS and then receives the sharing control authority.

10. The data format as claimed in claim 8, wherein the request rejecting message receiver receives the message rejecting the request for the sharing control authority when a SIFS elapses after the request message broadcaster broadcasts the sharing control authority requesting message.

11. The station as claimed in claim 6, wherein the first controller controls the sharing of the wireless hybrid resources when no other station among the stations has the sharing control authority.

12. A controller for generating a data format for use in a station for performing wireless hybrid resources sharing using a method for sharing wireless hybrid resources among stations in a wireless independent network, the controller generated data format comprising:

a control authority requesting message, which requests sharing control authority by a distributed coordination method;

a control authority releasing message, which releases the sharing control authority; and

a plurality of transmission frames, which are spaced apart from the control authority requesting message and the control authority releasing message, respectively, by a PIFS, are also spaced apart from each other by one PIFS, and have variable lengths, respectively.

13. The data format as claimed in claim 12, wherein each of the transmission frames comprises:

a downlink section in which real-time service-related data is transmitted to another station and which has a variable length;

a polling section in which the other station 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 has a variable length.

14. The data format as claimed in claim 13, wherein the downlink section is spaced apart from the polling section by a PIFS.

15. The data format as claimed in claim 13, wherein the polling section is spaced apart from the distribution control section by a DIFS.

16. The data format as claimed in claim 13, wherein the downlink section comprises a plurality of packets which are spaced apart from each other by a PIFS.

17. A method for sharing wireless resources among stations in a wireless network, the method comprising:

determining which station of the stations is to be a control station based on whether currently transmitted data transmitted by one station of the plurality of the stations satisfies a predetermined condition;

assigning sharing control authority to control the sharing of the wireless resources to the one station to make the one station the control station if a result of the determining is that the currently transmitted data transmitted by the one station satisfies the predetermined condition; and

controlling transmission of data by the one station after the sharing control authority has been assigned to the one station.

18. The method of claim 17, wherein the controlling further comprises controlling the transmission of data by the one station by a centralized control method; and

the method further comprises controlling transmission of data by the one station by a method other than the centralized control method if a result of the determining is that the currently transmitted data transmitted by the one station does not satisfy the predetermined condition.

19. The method of claim 17, further comprising releasing the sharing control authority assigned to the one station after the controlling of the transmission of the data by the one station.

20. The method of claim 17, wherein the predetermined condition is whether the currently transmitted data transmitted by the one station is related to a predetermined data type.

21. A station for performing a method for sharing wireless resources among stations in a wireless network, the station comprising:

a transmission data checking unit to determine whether the station is to be a control station based on whether currently transmitted data transmitted by the station satisfies a predetermined condition; and

a first controller to:

assign sharing control authority to control the sharing of the wireless resources to the station to make the station the control station if the transmission data checking unit determines that the currently transmitted data transmitted by the station satisfies the predetermined condition; and

control transmission of data by the station after the first controller has assigned the sharing control authority to the station.

22. The station of claim 21, wherein the first controller controls the transmission of data by the station by a centralized control method; and

the station further comprises a second controller to control transmission of data by the station by a method other than the centralized control method if the transmission data checking unit determines that the currently transmitted data transmitted by the station does not satisfy the predetermined condition.

23. The station of claim 21, wherein the first controller releases the sharing control authority assigned to the station after the first controller has controlled the transmission of the data by the station.

24. The station of claim 21, wherein the predetermined condition is whether the currently transmitted data transmitted by the station is related to a predetermined data type.