Allocating Resources in a Frequency-Time Space to Mobile Station Data

• US 20130028233A1
• Filed: 09/26/2012
• Published: 01/31/2013
• Est. Priority Date: 12/08/2006
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Bontu, Chandra, Hawryluck, Mark, Larijani, Parsya
• Granted Patent: US 9,191,164 B2
• Time in Patent Office: Days
• US Class Current: 370/330
• CPC Class Codes: H04J 11/00 Orthogonal multiplex systems, e.g. using WALSH codesH04J13/00 takes precedence
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0037 Inter-user or inter-terminal allocation
• CPC Class Codes: H04L 5/0069 Allocation based on distance or geographical location allocation based on terminal or device properties in general, H04W72/51
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames

Abstract

To allocate resources in an orthogonal frequency domain multiple access (OFDMA) system, two-dimensional rectangular regions are assigned in a frequency-time space to data bursts associated with mobile stations. At least one data burst does not fit in an available space in the frequency-time space is determined. In response to the determining, the assigned two-dimensional rectangular regions are reshaped.

Claims

1. A method of allocating resources in an orthogonal frequency domain multiple access (OFDMA) system, comprising:

a wireless device assigning two-dimensional rectangular regions in a frequency-time space to data bursts associated with mobile stations using at least one predefined shaping rule;

the wireless device determining that at least one data burst does not fit in an available space in the frequency-time space; and

in response to the determining, the wireless device reshaping the assigned two-dimensional rectangular regions, wherein reshaping the assigned two-dimensional rectangular region comprises modifying the at least one predefined shaping rule to adjust a shape of at least one rectangular region specified by the at least one predefined shaping rule.

2. The method of claim 1, wherein assigning the two-dimensional rectangular regions in the frequency-time space is based on a criterion that specifies that the frequency-time space is to be as fully utilized as possible.

3. The method of claim 1, further comprising:

applying a fitting algorithm to further define the two-dimensional rectangular regions, where the fitting algorithm assigns differently shaped two-dimensional regions to fast-moving mobile stations and to slow-moving mobile stations.

4. The method of claim 3, wherein the fitting algorithm uses a criterion that specifies that data burst errors is to be reduced.

5. The method of claim 3, wherein the fitting algorithm increases a ratio of a width of the rectangular region to a height of the rectangular region for a mobile station that is fast moving, and increases a ratio of a height of the rectangular region to a width of the rectangular region for a mobile station that is slow moving.

6. The method of claim 5, wherein the fitting algorithm specifies that the corresponding two-dimensional rectangular region is to be as close as possible to a square for a mobile station that is neither fast moving nor slow moving.

7. The method of claim 1, further comprising:

dividing a number of slots in the two-dimensional rectangular region allocated to each mobile station by prime factors;

providing the prime factors to a fitting algorithm; and

using, by the fitting algorithm, the prime factors to further shape the two-dimensional rectangular regions.

8. The method of claim 7, further comprising using combinations of the prime factors to define a height and a width of the two-dimensional rectangular region for each mobile station.

9. The method of claim 8, wherein using the prime factors to further shape the two-dimensional rectangular region for each mobile station comprises:

using the prime factors to define a wide, flat rectangular region for a fast-moving mobile station; and

using the prime factors to define a tall, skinny rectangular region for a slow-moving mobile station.

10. The method of claim 7, further comprising:

determining whether the number of slots is exactly divisible by the prime factors;

in response to determining that the number of slots is not exactly divisible by the prime factors, adjusting the number of slots in the corresponding two-dimensional rectangular region.

11. The method of claim 1, wherein assigning the two-dimensional rectangular regions in the frequency-time space comprises assigning the two-dimensional rectangular regions for downlink data bursts.

12. A base station comprising:

a wireless transceiver, configured to communicate with mobile stations; and

processing hardware coupled to the wireless transceiver, wherein the processing hardware is configured to implement a scheduler, wherein the scheduler is configured to;

assign data bursts associated with mobile stations communicated with the base station to two-dimensional rectangular regions in a frequency-time space; and

shape the two-dimensional rectangular regions based on speeds of the mobile stations.

13. The base station of claim 12, wherein the scheduler is configured to further:

determine that at least one data burst does not fit in an available space in the frequency-time space; and

in response to the determining, reshaping the assigned two-dimensional rectangular regions.

14. The base station of claim 13, wherein the scheduler is configured to further relax rules associated with shaping the two-dimensional rectangular regions according to the speeds of the mobile stations in reshaping the assigned two-dimensional rectangular regions.

21. The base station of claim 12, wherein the shaping of the two-dimensional rectangular regions is based on a first shaping rule for fast-moving mobile stations having speeds above a first threshold, and a second, different shaping rule for slow-moving mobile stations having speeds below a second threshold.

15. A non-transitory, computer-readable storage medium containing program instructions executable by a processor to:

assign two-dimensional rectangular regions in a frequency-time space to data bursts associated with mobile stations using at least one predefined shaping rule;

determine that at least one data burst does not fit in an available space in the frequency-time space; and

in response to the determining, reshape the assigned two-dimensional rectangular regions, wherein reshaping the assigned two-dimensional rectangular region comprises modifying the at least one predefined shaping rule to adjust a shape of at least one rectangular region specified by the at least one predefined shaping rule.

16. The non-transitory, computer-readable storage medium of claim 15, wherein the program instructions are further executable to:

apply a fitting algorithm to further shape the two-dimensional rectangular regions, where the fitting algorithm shapes the two-dimensional regions according to speeds of the mobile stations.

17. The non-transitory, computer-readable storage medium of claim 16, wherein the fitting algorithm increases a ratio of a width of the rectangular region to a height of the rectangular region for a mobile station that is fast moving, and increases a ratio of a height of the rectangular region to a width of the rectangular region for a mobile station that is slow moving.

18. The non-transitory, computer-readable storage medium of claim 17, wherein the fitting algorithm specifies that the corresponding two-dimensional rectangular region is to be as close as possible to a square for a mobile station that is neither fast moving nor slow moving.

19. The non-transitory, computer-readable storage medium of claim 15, wherein the program instructions are further executable to:

divide a number of slots in the two-dimensional rectangular region allocated to each mobile station by prime factors;

provide the prime factors to a fitting algorithm; and

use, by the fitting algorithm, the prime factors to further shape the two-dimensional rectangular regions.

20. The non-transitory, computer-readable storage medium of claim 15, wherein the program instructions are further executable to:

use combinations of the prime factors to define a height and a width of the two-dimensional rectangular region for each mobile station.