ADDRESSING MULTIPLE COMMUNICATION TERMINALS IN A WIRELESS COMMUNICATION NETWORK

• US 20140334368A1
• Filed: 11/09/2012
• Published: 11/13/2014
• Est. Priority Date: 11/09/2011
• Status: Active Grant

• Current Assignee: Agency For Science Technology and Research (Government of Singapore)
• Original Assignee: Agency For Science Technology and Research (Government of Singapore)
• Inventors: Lei, Zhongding, Sun, Sumei, Oh, Ser Wah, Zhou, Yuan
• Granted Patent: US 9,485,714 B2
• Time in Patent Office: Days
• US Class Current: 370/311
• CPC Class Codes: H04W 4/08 User group management
• CPC Class Codes: H04W 48/10 using broadcasted information
• CPC Class Codes: H04W 48/12 using downlink control channel
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

The present invention is directed to a communication device of a wireless communication network, the communication device including a message generator configured to generate a beacon message having a traffic indication map (TIM) information element (IE), wherein the TIM IE includes a partial virtual bitmap field including at least one cluster; a determiner configured to determine for at least one cluster information indicating whether data is available in the communication device to be transmitted to a plurality of communication terminals of the wireless communication network; an encoder configured to determine an encoding mode for the information depending on the information and to encode the information based on the encoding mode; and a transmitter configured to broadcast the beacon message to the plurality of communication terminals corresponding to the at least one cluster. Methods of simultaneously addressing a plurality of communication terminals in the wireless communication network are also disclosed.

Claims

1. A communication device of a wireless communication network, the communication device comprising:

a message generator configured to generate a beacon message having a traffic indication map (TIM) information element (IE), wherein the TIM IE comprises a partial virtual bitmap field comprising at least one cluster, and a bitmap control field indicating the number of clusters in the partial virtual bitmap field;

a determiner configured to determine for the at least one cluster information indicating whether data is available in the communication device to be transmitted to a plurality of communication terminals of the wireless communication network;

an encoder configured to determine an encoding mode for the information depending on the information and to encode the information based on the encoding mode, wherein the at least one cluster comprises the encoded information and indicates the encoding mode; and

a transmitter configured to broadcast the beacon message to the plurality of communication terminals corresponding to the at least one cluster.

7. The communication device of claim 1, wherein the encoder is configured to determine the encoding mode based on the number of bits in the information that is set, or a distribution of the bits in the information that is set, or the number of communication terminals that the communication device intends to address, or the complexity level of decoding the encoding mode, or any combination thereof.

8. The communication device of claim 1, wherein the encoded information comprises a plurality of association identities (AIDs), by each of which a communication terminal of the plurality of communication terminals is identified.

9. The communication device of claim 1, further comprising a grouping determiner configured to divide the plurality of communication terminals of the wireless communication network into groups.

11. The communication device of claim 1, wherein the encoded information comprises a first bitmap, and a first control field for the first bitmap.

13. The communication device of claim 11, wherein the encoded information further comprises information about the group corresponding to a group identity (GID).

14. The communication device of claim 13, wherein the encoded information comprises:

a first part indicative of a number of groups (G) of communication terminals of the wireless communication network; and

a second part including G segments, each segment comprising a second bitmap and a second control field for the second bitmap; and

being associated to the group identity (GID),

wherein the information about the group corresponds to the first part and the second control field of the second part; and

wherein the first bitmap corresponds to the second bitmap of the second part.

15. The communication device of claim 14, wherein for the segment of the second part, the second control field comprises an offset value for the second bitmap.

16. The communication device of claim 14, wherein the GID is determined based on a mathematical formulation of an association identity (AID) of a communication terminal of a group from the groups of communication terminals and the number of communication terminals (N) in the group, as given by

Modulus(AID of the communication terminal/N).

19. The communication device of claim 14, wherein the GID is determined based on a mathematical function of a Time Synchronization Function (TSF) of a communication terminal of a group from the groups of communication terminals, a beacon interval (BI) of the beacon message, and the number of groups (G) of communication terminals, as given by

Remainder(Modulus(TSF,BI)/G).

21. The communication device of claim 14, wherein the second bitmap is inversely coded depending on the second control field.

22. The communication device of claim 14, wherein the first bitmap is inversely coded depending on the first control field.

23. The communication device of claim 22, wherein the first control field or the second control field further comprises a sign bit configured to set to a first state indicating that the first bitmap or the second bitmap is coded or to a second state indicating that the first bitmap or the second bitmap is inversely coded, the first state being different from the second state.

24. The communication device of claim 13,

wherein the information about the group comprises

a part indicative of a number of groups (G) of communication devices of the wireless communication network;

and

a group indicator map (GIM) field with G bits, each of the G bits corresponding to a group of communication terminals from the groups of communication terminals; and

wherein the first bitmap is arranged to be decoded by the group of communication terminals depending on a state of the corresponding bit in the GIM field.

2-6. -6. (canceled)

10. (canceled)

12. (canceled)

17-18. -18. (canceled)

20. (canceled)

25-27. -27. (canceled)

28. A communication terminal according to claim further comprising:

a receiver configured to receive from a communication device of the wireless communication network a beacon message having a traffic indication map (TIM) information element (IE), wherein the TIM IE comprises a partial virtual bitmap field comprising at least one cluster, and a bitmap control field indicating the number of clusters in the partial virtual bitmap field, and wherein the at least one cluster comprises an encoded information and indicates an encoding mode;

a decoder configured to decode the encoded information based on the encoding mode;

a determiner configured to determine based on the information whether the communication terminal is to retrieve data from the communication device,

wherein the beacon message is for a group of communication terminals; and

wherein the communication terminal is part of the group.

32. The communication terminal of claim 28,

wherein the decoded information comprises a plurality of association identities (AIDS), by each of which a communication terminal is identified in the wireless communication network;

and

wherein the determiner is configured to determine that the communication terminal is to retrieve a buffered data from the communication device if the AID of the communication terminal matches one of the plurality of AIDs of the decoded information;

or to determine that the communication terminal is to be in a power saving mode if the AID of the communication terminal fails to match any of the plurality of AIDs of the decoded information.

33. The communication terminal of claim 28,

wherein the decoded information comprises a first bitmap;

and information about the group corresponding to a group identity (GID); and

wherein the determiner is configured to determine that the communication terminal is to retrieve a buffered data from the communication device if the GID and the AID of the communication terminal respectively match the information about the group and an address of the first bitmap;

or to determine that the communication terminal is to be in a power saving mode if at least one of the GID and the AID of the communication terminal fails to match the information about the group and any address of the first bitmap respectively.

34. The communication terminal of claim 33,

wherein the decoded information comprises a first part indicative of a number of groups (G) of communication terminals of the wireless communication network;

and a second part including G segments, each segment comprising a second bitmap and a second control field for the second bitmap; and

being associated to a group identity (GID),

wherein the information about the group corresponds to the first part and the second control field of the second part; and

wherein the first bitmap corresponds to the second bitmap of the second part; and

wherein the determiner is configured to determine that the communication terminal is to retrieve the buffered data from the communication device if the GID and the AID of the communication terminal respectively match the GID and a bitmap address of the segment;

or to determine that the communication terminal is to be in the power saving mode if at least one of the GID and the AID of the communication terminal fails to match the GID and any bitmap address of the segment respectively.

29-31. -31. (canceled)

35-36. -36. (canceled)

37. A method of simultaneously addressing a plurality of communication terminals of a wireless communication network, the method comprising:

generating a beacon message having a traffic indication map (TIM) information element (IE), wherein the TIM IE comprises a partial virtual bitmap field comprising at least one cluster, and a bitmap control field indicating the number of clusters in the partial virtual bitmap field;

determining for the at least one cluster information indicating whether data is available in a communication device to be transmitted to the plurality of communication terminals of the wireless communication network;

determining an encoding mode for the information depending on the information and encoding the information based on the encoding mode, wherein the at least one cluster comprises the encoded information and indicates the encoding mode;

and

broadcasting the beacon message to the plurality of communication terminals corresponding to the at least one cluster.

38. The method of claim 37, further comprising:

receiving from a communication device of the wireless communication network a beacon message having a traffic indication map (TIM) information element (IE), wherein the TIM IE comprises a partial virtual bitmap field comprising at least one cluster, and a bitmap control field indicating the number of clusters in the partial virtual bitmap field, and wherein the at least one cluster comprises an encoded information and indicates an encoding mode;

decoding the encoded information based on the encoding mode;

determining based on the information whether the communication terminal is to retrieve data from the communication device,

wherein the beacon message is for a group of communication terminals; and

wherein the communication terminal is part of the group.

39-72. -72. (canceled)