METHOD AND APPARATUS FOR UPLINK SCHEDULING IN AN ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING COMMUNICATION SYSTEM

• US 20100303022A1
• Filed: 05/27/2009
• Published: 12/02/2010
• Est. Priority Date: 05/27/2009
• Status: Active Grant

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Maas, David R., Mu, Chen
• Granted Patent: US 8,559,458 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• 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 5/0058 Allocation criteria
• CPC Class Codes: H04W 72/569 of the traffic information

Abstract

A method and scheduler are provided that optimize utilization of an uplink (UL) data packet field of an UL sub-frame. In one embodiment, a request for an allocation of bandwidth is received from each of multiple mobile stations. The requests include requests for a bandwidth allocation of a first size range and requests for a bandwidth allocation of a second size range, wherein each request of the second size range requests more bandwidth than any request of the first size range. Bandwidth is allocated in a UL data packet field to the requests in order of priority, and when the allocated bandwidth does not fill the UL data packet field and a request of the second size range remains unallocated, an allocation of bandwidth to an unallocated request of the second size range is substituted for an allocation of bandwidth to a request of the first size range.

Claims

1. A method for uplink scheduling in an Orthogonal Frequency Division Multiplexing communication system, the method comprising:

receiving, from each mobile station of a plurality of mobile stations, a request for an allocation of bandwidth, wherein the requests comprise one or more requests for a bandwidth allocation of a first size range and one or more requests for a bandwidth allocation of a second size range and wherein each bandwidth allocation request of the second size range requests more bandwidth than any bandwidth allocation request of the first size range;

allocating bandwidth in an uplink data packet field of an uplink sub-frame to the bandwidth allocation requests in order of priority; and

when the allocated bandwidth does not fill the uplink data packet field and one or more bandwidth allocation requests of the second size range remains unallocated, substituting an allocation of bandwidth to an unallocated bandwidth allocation request of the second size range for an allocation of bandwidth to a bandwidth allocation request of the first size range in the uplink data packet field.

2. The method of claim 1, wherein a bandwidth allocation request of the first size range is a request for an allocation of bandwidth of ten or fewer bytes.

3. The method of claim 1, wherein substituting comprises substituting an allocation of bandwidth to a highest priority, unallocated bandwidth allocation request of the second size range for an allocation of bandwidth to a lowest priority bandwidth allocation request of the first size range in the uplink data packet field.

4. The method of claim 3, further comprising, in response to substituting an allocation of bandwidth to a highest priority, unallocated bandwidth allocation request of the second size range for an allocation of bandwidth to a lowest priority bandwidth allocation request of the first size range in the uplink data packet field:

determining that the allocated bandwidth still does not fill the uplink data packet field;

determining that one or more bandwidth allocation requests of the second size range remains unallocated; and

substituting an allocation of bandwidth to a next highest priority, unallocated bandwidth allocation request of the second size range for an allocation of bandwidth to a next lowest priority bandwidth allocation request of the first size range in the uplink data packet field.

5. A method for uplink scheduling in an Orthogonal Frequency Division Multiplexing communication system, the method comprising:

receiving, from each mobile station of a plurality of mobile stations, a request for an allocation of bandwidth, wherein the requests comprise one or more requests are for a bandwidth allocation of a first size range and one or more requests are for a bandwidth allocation of a second size range and wherein each bandwidth allocation request of the second size range requests more bandwidth than any bandwidth allocation request of the first size range;

determining a number of registered mobile stations in a coverage area; and

determining a maximum number of bandwidth allocation requests of the first size range that can be scheduled for an uplink data packet field of an uplink sub-frame based on the determined number of registered mobile stations in the coverage area.

6. The method of claim 5, further comprising allowing a scheduling of additional bandwidth allocation requests of the first size in excess of the maximum number determined in the event that all bandwidth allocation requests of the second size have been granted and additional space remains in the uplink data packet field of the uplink sub-frame.

7. The method of claim 5, wherein determining a maximum number of bandwidth allocation requests of the first size range that can be scheduled for an uplink data packet field of an uplink sub-frame comprises:

comparing the determined number of registered mobile stations in the coverage area to one or more thresholds to produce one or more comparisons; and

determining a maximum number of bandwidth allocation requests of the first size range that can be scheduled for an uplink data packet field of an uplink sub-frame based on the one or more comparisons.

8. The method of claim 7, wherein determining a maximum number of bandwidth allocation requests of the first size range that can be scheduled for an uplink data packet field of an uplink sub-frame based on the one or more comparisons comprise referencing a table that maintains, in association with each threshold value of the one or more threshold values, a maximum number of bandwidth allocation requests of the first size range that can be scheduled for a scheduling time period.

9. The method of claim 5, wherein the larger the determined number of registered mobile stations in the coverage area, the smaller the maximum number of bandwidth allocation requests of the first size range that can be scheduled for the uplink data packet field.

10. A scheduler operable in an Orthogonal Frequency Division Multiplexing communication system, the scheduler comprising:

an at least one memory device

a processor that is configured to receive, from each mobile station of a plurality of mobile stations, and store in the at least one memory device, a request for an allocation of bandwidth, wherein the requests comprise one or more requests for a bandwidth allocation of a first size range and one or more requests for a bandwidth allocation of a second size range and wherein each bandwidth allocation request of the second size range requests more bandwidth than any bandwidth allocation request of the first size range, allocate bandwidth in an uplink data packet field of an uplink sub-frame to the bandwidth allocation requests in order of priority, and when the allocated bandwidth does not fill the uplink data packet field and one or more bandwidth allocation requests of the second size range remains unallocated, substitute an allocation of bandwidth to an unallocated bandwidth allocation request of the second size range for an allocation of bandwidth to a bandwidth allocation request of the first size range in the uplink data packet field.

11. The scheduler of claim 10, wherein a bandwidth allocation request of the first size range is a request for an allocation of bandwidth of ten or fewer bytes.

12. The scheduler of claim 10, wherein the processor is configured to substitute allocations of bandwidth by substituting an allocation of bandwidth to a highest priority, unallocated bandwidth allocation request of the second size range for an allocation of bandwidth to a lowest priority bandwidth allocation request of the first size range in the uplink data packet field.

13. The scheduler of claim 12, wherein the processor is configured to, in response to substituting an allocation of bandwidth to a highest priority, unallocated bandwidth allocation request of the second size range for an allocation of bandwidth to a lowest priority bandwidth allocation request of the first size range in the uplink data packet field:

determine that the allocated bandwidth still does not fill the uplink data packet field;

determine that one or more bandwidth allocation requests of the second size range remains unallocated; and

substitute an allocation of bandwidth to a next highest priority, unallocated bandwidth allocation request of the second size range for an allocation of bandwidth to a next lowest priority bandwidth allocation request of the first size range in the uplink data packet field.

14. A scheduler operable in an Orthogonal Frequency Division Multiplexing communication system, the scheduler the scheduler comprising:

an at least one memory device

a processor that is configured to receive, from each mobile station of a plurality of mobile stations, and store in the at least one memory device, a request for an allocation of bandwidth, wherein the requests comprise one or more requests are for a bandwidth allocation of a first size range and one or more requests are for a bandwidth allocation of a second size range and wherein each bandwidth allocation request of the second size range requests more bandwidth than any bandwidth allocation request of the first size range, determine a number of registered mobile stations in a coverage area, and determine a maximum number of bandwidth allocation requests of the first size range that can be scheduled for an uplink data packet field of an uplink sub-frame based on the determined number of registered mobile stations in the coverage area.

15. The scheduler of claim 14, wherein the processor is configured to allow a scheduling of the additional bandwidth allocation requests of the first size in excess of the maximum number determined in the event that all bandwidth allocation requests of the second size have been granted and additional space remains in the uplink data packet field of an uplink sub-frame.

16. The scheduler of claim 14, wherein the processor is configured to determine a maximum number of bandwidth allocation requests of the first size range that can be scheduled for an uplink data packet field of an uplink sub-frame by comparing the determined number of registered mobile stations in the coverage area to one or more thresholds to produce one or more comparisons and determining a maximum number of bandwidth allocation requests of the first size range that can be scheduled for an uplink data packet field of an uplink sub-frame based on the one or more comparisons.

17. The scheduler of claim 16, wherein processor is configured to determine a maximum number of bandwidth allocation requests of the first size range that can be scheduled for an uplink data packet field of an uplink sub-frame based on the one or more comparisons by referencing a table maintained in the at least one memory device, where the table maintains, in association with each threshold value of the one or more threshold values, a maximum number of bandwidth allocation requests of the first size range that can be scheduled for a scheduling time period.

18. The scheduler of claim 14, wherein the larger the determined number of registered mobile stations in the coverage area, the smaller the maximum number of bandwidth allocation requests of the first size range that can be scheduled for the uplink data packet field.