Wireless Network Throughput Enhancement Through Channel Aware Scheduling

• US 20090028095A1
• Filed: 07/28/2008
• Published: 01/29/2009
• Est. Priority Date: 07/28/2007
• Status: Active Grant

• Current Assignee: Ruckus IP Holdings LLC
• Original Assignee: Ruckus Wireless, Inc. (CommScope Holding Company, Inc.)
• Inventors: Kish, William S.
• Granted Patent: US 8,547,899 B2
• Time in Patent Office: Days
• US Class Current: 370/328
• CPC Class Codes: H04W 72/535 based on resource usage policies
• CPC Class Codes: H04W 72/569 of the traffic information
• CPC Class Codes: H04W 80/04 Network layer protocols, e.g. mobile IP [Internet Protocol]
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

A channel aware scheduler (CAS) is disclosed that takes advantage of changing wireless channel conditions in order to maximize aggregated system throughput. The CAS is aware of the different channel conditions for one or more stations and adjusts its scheduling of packet transmissions in light of the same. A related CAS algorithm may take advantage of that knowledge in order to increase aggregated system throughput while concurrently addressing other potential fairness constraints.

Claims

1. A system for increasing wireless network throughput, comprising:

a classifier configured to assign a packet to one of a plurality of transmission queues;

a first scheduling module stored in a computer-readable medium and executable by a processing device, the first scheduling module configured to select an assigned packet for transmission from one of the plurality of transmission queues in accordance with a strict priority schedule; and

a second scheduling module stored in a computer-readable medium and executable by a processing device, the second scheduling module configured to select a priority scheduled packet for transmission, wherein the selection is made in accordance with a weighted scheduling technique.

2. The system of claim 1, whereupon receipt of a retransmission request by the second scheduling module, the second scheduling module defers re-transmission of the packet and initiates transmission of pending packets for another queue.

3. The system of claim 1, further comprising a credit register associated with each of the plurality of transmission queues.

4. The system of claim 3, wherein the credit register is decremented for each re-transmission request received for a packet transmitted from the transmission queue.

5. The system of claim 4, wherein decrementing a credit register for a transmission queue to zero activates another transmission queue.

6. The system of claim 1, further comprising a feedback module stored in a computer-readable medium and executable by a processing device, the feedback module configured to modify a weight assigned to a transmission queue such that the scheduler favors stations with a more efficient channel.

7. A method for increasing wireless throughput, comprising:

assigning a packet to one of a plurality of transmission queues;

selecting an assigned packet for transmission from one of the plurality of transmission queues in accordance with a priority schedule;

selecting a priority scheduled packet for transmission in accordance with a weighted scheduling technique; and

transmitting the packet.

8. The method of claim 7, further comprising modifying queue weights associated with a weighted scheduling technique to reflect channel conditions, the queue weights favoring stations with a higher quality channel.

9. The method of claim 7, wherein queue weights associated with the weighted scheduling technique are proportional to channel capacities.

10. The method of claim 9, wherein channel capacity is increased.

11. The method of claim 7, wherein aggregate system throughput is increased while maintaining at least one potential fairness constraint.

12. A computer-readable storage medium having embodied thereon a program, the program being executable by a processing device to perform a method for increasing wireless throughput, comprising:

assigning a packet to one of a plurality of transmission queues;

selecting an assigned packet for transmission from one of the plurality of transmission queues in accordance with a priority schedule;

selecting a priority scheduled packet for transmission in accordance with a weighted scheduling technique; and

transmitting the packet.

13. The computer-readable storage medium of claim 12, wherein the program is further executable to modify queue weights associated with a weighted scheduling technique to reflect channel conditions, the queue weights favoring stations with a higher quality channel.

14. The computer-readable storage medium of claim 13, wherein queue weights associated with the weighted scheduling technique are proportional to channel capacities.

15. The computer-readable storage medium of claim 13, wherein aggregate system throughput is increased while maintaining at least one potential fairness constraint.