Scheduling based on channel change indicia

• US 7,463,616 B1
• Filed: 03/28/2002
• Issued: 12/09/2008
• Est. Priority Date: 03/28/2002
• Status: Expired due to Fees

• Current Assignee: Apple Inc.
• Original Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Inventors: Earnshaw, Mark, Hashem, Bassam M., Cheong, Yoon Chae
• Primary Examiner(s): Orgad, Edan
• Assistant Examiner(s): LEE, ANDREW CHUNG CHEUNG
• Application Number:
  US10/108,624
• Time in Patent Office: 2,448 Days
• Field of Search: 370/337, 370/339, 370/329, 370/341, 370/347, 370/431, 370/442, 455/522, 455/69, 455/450, 455/67.11, 455/452.1, 455/452
• US Class Current: 370/347
• CPC Class Codes: H04W 72/542 using measured or perceived quality

Abstract

The present invention keeps track of channel change indicia associated with wireless communications with mobile terminals, and bases the scheduling of data in time slots of a scheduling period on the channel change indicia. The channel change indicia may be derived from any information that bears on the rate at which channel conditions are likely to change, such as the velocity the mobile terminals are traveling or actual channel condition measurements. Preferably, mobile terminals associated with intermediate values for the channel change indicia are given priority, and thus, scheduled for transmission before those with lower and higher values. The invention is applicable to uplink and downlink communications, and is particularly beneficial when implemented in uplink and downlink schedulers in a base station.

Claims

1. A method for scheduling communications in a wireless communication environment for a plurality of terminals comprising:

a) scheduling communications for a plurality of terminals to a scheduling period having a plurality of time slots;

b) determining channel change indicia associated with each of the plurality of terminals having communications scheduled during the scheduling period; and

c) scheduling the communications to an assigned time slot within the scheduling period based on the channel change indicia,

wherein the communications for any one of the plurality of terminals occurs during the assigned time slot within the scheduling period, and

wherein the channel change indicia can have low, intermediate, and high values and the communications associated with intermediate channel change indicia values are scheduled for time slots at a beginning of the scheduling period and ahead of communications associated with the low and high channel change indicia values, the values for channel change indicia proportional to a rate at which channel conditions are likely to change.

2. The method of claim 1 wherein the channel change indicia bears on a rate at which channel conditions are likely to change.

3. The method of claim 1 wherein the channel change indicia for at least one of the plurality of terminals bears on a rate at which actual channel conditions are changing and is derived from periodic measurements of the channel conditions.

4. The method of claim 1 wherein the channel change indicia for at least one of the plurality of terminals bears on a rate at which the terminal is moving.

5. The method of claim 1 wherein the communications associated with higher ones of the intermediate channel change indicia values are scheduled before lower ones of the intermediate channel change indicia values.

6. The method of claim 1 further comprising allocating resources to effect the communications based on error rates for previous communications for corresponding ones of the plurality of terminals.

7. The method of claim 1 wherein the communications are uplink communications and further comprising transmitting control information to one of the plurality of terminals wherein the control information includes the assigned time slot for transmitting data to a base station used to effect communications for the one of the plurality of terminals.

8. The method of claim 7 further comprising allocating communication resources for communications associated with the one of the plurality of terminals and providing indicia bearing on the communication resources allocated for communications in the control information.

9. The method of claim 8 wherein the communication resources bear on a transmit power the one of the plurality of terminals should use when transmitting data to effect communications.

10. The method of claim 1 wherein the communications are downlink communications and further comprising transmitting data to the plurality of terminals during the assigned time slots to effect communications.

11. The method of claim 10 further comprising allocating communication resources for communications associated with the one of the plurality of terminals.

12. The method of claim 11 wherein the resources bear on at least one of a group consisting of coding rates, modulation techniques, and data rates for transmitting data to the one of the plurality of terminals to effect communications.

13. A base station for scheduling communications in a wireless communication environment for a plurality of terminals comprising:

a) wireless communication circuitry for communicating with a plurality of terminals; and

b) a scheduler operatively associated with the wireless communication circuitry for;

i) scheduling communications for the plurality of terminals to a scheduling period having a plurality of time slots;

ii) determining channel change indicia associated with each of the plurality of terminals having communications scheduled during the scheduling period; and

iii) scheduling the communications to an assigned time slot within the scheduling period based on the channel change indicia,

wherein the communications for any one of the plurality of terminals occurs during the assigned time slot within the scheduling period, and

wherein the channel change indicia can have low, intermediate, and high values and the communications associated with intermediate channel change indicia values are scheduled for time slots at a beginning of the scheduling period and ahead of communications associated with the low and high channel change indicia values, the values for channel change indicia proportional to a rate at which channel conditions are likely to change.

14. The base station of claim 13 wherein the channel change indicia bears on a rate at which channel conditions are likely to change.

15. The base station of claim 13 wherein the channel change indicia for at least one of the plurality of terminals bears on a rate at which actual channel conditions are changing and is derived from periodic measurements of the channel conditions.

16. The base station of claim 13 wherein the channel change indicia for at least one of the plurality of terminals bears on a rate at which the terminal is moving.

17. The base station of claim 13 wherein the communications associated with higher ones of the intermediate channel change indicia values are scheduled before lower ones of the intermediate channel change indicia values.

18. The base station of claim 13 wherein the scheduler is further adapted to allocate resources to effect the communications based on error rates for previous communications for corresponding ones of the plurality of terminals.

19. The base station of claim 13 wherein the communications are uplink communications and the scheduler is further adapted to cooperate with the wireless communication circuitry to transmit control information to one of the plurality of terminals wherein the control information includes the assigned time slot for transmitting data to the base station used to effect communications for the one of the plurality of terminals.

20. The base station of claim 19 wherein the scheduler is further adapted to allocate communication resources for communications associated with the one of the plurality of terminals and providing indicia bearing on the communication resources allocated for communications in the control information.

21. The base station of claim 20 wherein the resources bear on a transmit power the one of the plurality of terminals should use when transmitting data to effect communications.

22. The base station of claim 13 wherein the communications are downlink communications and the scheduler is further adapted to cooperate with the wireless communication circuitry to transmit data to the plurality of terminals during the assigned time slots to effect communications.

23. The base station of claim 22 wherein the scheduler is further adapted to allocate communication resources for communications associated with the one of the plurality of terminals.

24. The base station of claim 23 wherein the resources bear on at least one of a group consisting of coding rates, modulation techniques, and data rates for transmitting data to the one of the plurality of terminals to effect communications.

25. An apparatus for scheduling communications in a wireless communication environment for a plurality of terminals comprising:

a) means for scheduling communications for a plurality of terminals to a scheduling period having a plurality of time slots;

b) means for determining channel change indicia associated with each of the plurality of terminals having communications scheduled during the scheduling period; and

c) means for scheduling the communications to an assigned time slot within the scheduling period based on the channel change indicia,

wherein the communications for any one of the plurality of terminals occurs during the assigned time slot within the scheduling period, and

wherein the channel change indicia can have low, intermediate, and high values and the communications associated with intermediate channel change indicia values are scheduled for time slots at a beginning of the scheduling period and ahead of communications associated with the low and high channel change indicia values, the values for channel change indicia proportional to a rate at which channel conditions are likely to change.

26. The apparatus of claim 25 wherein the channel change indicia bears on a rate at which channel conditions are likely to change.

27. The apparatus of claim 25 wherein the channel change indicia for at least one of the plurality of terminals bears on a rate at which actual channel conditions are changing and is derived from periodic measurements of the channel conditions.

28. The apparatus of claim 25 wherein the channel change indicia for at least one of the plurality of terminals bears on a rate at which the terminal is moving.