Methods and apparatuses for allocating time slots to half duplex wireless mobile stations

• US 20040057407A1
• Filed: 09/24/2002
• Published: 03/25/2004
• Est. Priority Date: 09/24/2002
• Status: Active Grant

• Current Assignee: RPX Corporation
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Balachandran, Krishna, Luo, Wei, Nanda, Sanjiv, Chang, Kirk K.
• Granted Patent: US 7,352,714 B2
• Time in Patent Office: Days
• US Class Current: 370/336
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames

Abstract

Methods and apparatuses for allocating control and data time slots to a plurality of wireless mobile stations in a wireless communication system using time division multiplexing. The methods and apparatuses assign such time slots by first placing the wireless mobile stations into a number of different groups. Then, control time slots and anchor data time slots are assigned to the groups in the uplink and downlink frames of a carrier such that the uplink control time slot for each group is maximally spaced in time relative to the downlink control time slot for the same group. Data time slots are subsequently assigned to a particular mobile station by assigning time slots in the uplink and downlink frames which are as close as possible to the group'"'"'s uplink or downlink anchor data time slots, as the case may be, according to a “grow from center” technique.

Claims

1. A method of allocating time slots to wireless mobile stations comprising:

assigning a control time slot of a time frame of a first carrier to a plurality of wireless mobile stations, wherein the time frame of the first carrier is associated with wireless communication in a first direction;

assigning a control time slot of a time frame of a second carrier to the plurality of wireless mobile stations, wherein the time frame of the second carrier is associated with wireless communication in a second direction; and

wherein the position in time of the control time slot of the time frame of the second carrier is substantially midway between the positions in time of the control time slot of the time frame of the first carrier in consecutively communicated time frames of the first carrier.

2. The method of claim 1, wherein the position in time of the control time slot of the time frame of the second carrier is maximally spaced in time relative to the positions in time of the control time slot of the time frame of the first carrier in consecutively communicated time frames of the first carrier.

3. The method of claim 1, wherein the plurality of wireless mobile stations is a first plurality of wireless mobile stations, wherein the control time slot of the time frame of the first carrier is a first control time slot of the time frame of the first carrier, wherein the control time slot of the time frame of the second carrier is a first control time slot of the time frame of the second carrier, wherein the method further comprises:

assigning a second control time slot of the time frame of the second carrier to a second plurality of wireless mobile stations, and

assigning a second control time slot of the time frame of the first carrier to the second plurality of wireless mobile stations; and

wherein the position in time of the second control time slot of the time frame of the first carrier is substantially midway between the positions in time of the second control time slot of the time frame of the second carrier in consecutively communicated time frames of the second carrier.

4. The method of claim 3, wherein the position in time of the second control time slot of the time frame of the first carrier is maximally spaced in time relative to the positions in time of the second control time slot of the time frame of the second carrier in consecutively communicated time frames of the second carrier.

5. The method of claim 1, wherein the method further comprises assigning to a particular wireless mobile station of the plurality of wireless mobile stations a data time slot proximate in time to the control time slot of the time frame of the first carrier.

6. The method of claim 5, wherein the data time slot is adjacent in time to the control time slot of the time frame of the first carrier.

7. The method of claim 6, wherein the data time slot precedes in time the control time slot of the time frame of the first carrier.

8. The method of claim 6, wherein the data time slot follows in time the control time slot of the time frame of the first carrier.

9. The method of claim 5, wherein the data time slot is a first data time slot preceding in time the control time slot of the time frame of the first carrier, and wherein the method further comprises assigning to the particular wireless mobile station of the plurality of wireless mobile stations a second data time slot proximate and following in time the control time slot of the time frame of the first carrier.

10. The method of claim 5, wherein the method further comprises assigning a data time slot of a timeframe of a third carrier to the wireless mobile station of the plurality of wireless mobile stations that coincides with the position in time of the control time slot of the time frame of the first carrier, wherein the time frame of the third carrier is associated with wireless communication in the first direction.

11. An apparatus for allocating time slots to a plurality of wireless mobile stations in a wireless communication system, said apparatus comprising:

a controller adapted to;

assign a control time slot of a time frame of a first carrier to a plurality of wireless mobile stations, wherein said time frame of said first carrier is associated with wireless communication in a first direction;

assign a control time slot of a time frame of a second carrier to the plurality of wireless mobile stations, wherein said time frame of said second carrier is associated with wireless communication in a second direction; and

wherein the position in time of said control time slot of said time frame of said second carrier is substantially midway between the positions in time of said control time slot of said time frame of said first carrier in consecutively communicated time frames of said first carrier.

12. The apparatus of claim 11, wherein the position in time of said control time slot of said time frame of said second carrier is maximally spaced in time relative to the positions in time of said control time slot of said time frame of said first carrier in consecutively communicated time frames of said first carrier.

13. The apparatus of claim 11, wherein said plurality of wireless mobile stations is a first plurality of wireless mobile stations, wherein said control time slot of said time frame of said first carrier is a first control time slot of said time frame of said first carrier, wherein said control time slot of said time frame of said second carrier is a first control time slot of said time frame of said second carrier, wherein said controller is further adapted to:

assign a second control time slot of said time frame of said second carrier to a second plurality of wireless mobile stations;

assign a second control time slot of said time frame of said first carrier to said second plurality of wireless mobile stations; and

wherein the position in time of said second control time slot of said time frame of said first carrier is substantially midway between the positions in time of said second control time slot of said time frame of said second carrier in consecutively communicated time frames of said second carrier.

14. The apparatus of claim 11, wherein said controller is further adapted to assign to a particular wireless mobile station of said plurality of wireless mobile stations a data time slot as near as possible to said control time slot in time regardless of whether the position of said data time slot in time precedes or follows the position of said control time slot in time relative to the start of said time frame of said first carrier.

15. The apparatus of claim 14, wherein said data time slot is adjacent in time to said control time slot of said time frame of said first carrier.

16. The apparatus of claim 14, wherein said controller is further adapted to assign to a particular wireless mobile station of said plurality of wireless mobile stations a plurality of data time slots which are positioned in a direction extending away from the position in time of said control time slot relative to the start of said time frame of said first carrier.

17. The apparatus of claim 14, wherein said apparatus is further adapted to assign a data time slot of a time frame of a second carrier to said wireless mobile station of said plurality of wireless mobile stations that coincides with the position in time of said control time slot of said time frame of said first carrier, wherein said time frame of said second carrier is associated with wireless communication in said first direction.

18. A method of allocating time slots to wireless mobile stations in a wireless communication system, the method comprising:

receiving a request from a wireless mobile station for a particular number of data time slots of a time frame of a carrier for wirelessly communicating data in a first direction;

identifying an anchor data time slot of the time frame of the carrier;

determining whether data time slots proximate the anchor data time slot and equal in number to the requested number of data time slots are available for use by the wireless mobile station;

upon determining that the particular number of data time slots are available, selecting particular data time slots of the time frame of the carrier for assignment to the wireless mobile station; and

,

assigning the selected data time slots to the wireless mobile station.

19. The method of claim 18, wherein selecting includes selecting data time slots as near as possible to the anchor data time slot regardless of whether the positions of the data time slots in time precede or follow the position of the anchor data time slot in time relative to the start of the time frame of the carrier.

20. The method of claim 18, wherein selecting includes selecting data time slots adjacently positioned in time relative to one another for assignment to the wireless mobile station.