Method for scheduling guaranteed bit rate service based on quality of service

• US 20120320745A1
• Filed: 05/20/2010
• Published: 12/20/2012
• Est. Priority Date: 05/20/2010
• Status: Active Grant

• Current Assignee: ZTE Corporation
• Original Assignee: ZTE Corporation
• Inventors: Yu, Yong, Lu, Tao, Shi, Xianwen
• Granted Patent: US 8,837,284 B2
• Time in Patent Office: Days
• US Class Current: 370/230
• CPC Class Codes: H04L 47/801 Real time traffic
• CPC Class Codes: H04L 47/805 QOS or priority aware
• CPC Class Codes: H04W 72/566 of the information or information source or recipient

Abstract

The disclosure discloses a method for scheduling a Guaranteed Bit Rate (GBR) service based on Quality of Service (QoS) and an apparatus implementing the method, wherein the method comprises the steps of: determining a scheduling priority of an online user according to an average rate of a GBR service of the user in a current Transmission Time Interval (TTI); and scheduling the user in accordance with the determined priority and allocating Resource Block (RB) resources to the user. With the scheduling method of the disclosure, the RB resource can be fully utilized, and the user rate which does not reach the GBR is quickly improved to make as many users as possible to reach the GBR, so as to increase the number of satisfied users in system. For the case in which a Maximum Bit Rate (MBR) is greater than the GBR, on the basis that as many users as possible are made to reach the GBR, the rates of the users can be further improved to increase the number of users with high rates.

Claims

1. A method for scheduling a Guaranteed Bit Rate (GBR) service based on Quality of Service (QoS), comprising:

determining a scheduling priority of an online user according to an average rate of a GBR service of the user in a current Transmission Time Interval (TTI); and

scheduling the user in accordance with the determined priority and allocating Resource Block (RB) resources to the user.

2. The method according to claim 1, wherein the determining the scheduling priority of the online user according to the average rate of the GBR service of the user in the current TTI is:

determining the scheduling priority of the user according to a Proportional Fair (PF) scheduling algorithm in conjunction with QoS of the GBR service of the user.

3. The method according to claim 2, wherein the determining the scheduling priority of the user according to the PF scheduling algorithm in conjunction with QoS of the GBR service of the user is determining a scheduling priority Fair Factor (FF) of the user according to a following formula:

FF=FF_PF·

FF_GBR

where

4. The method according to claim 3, wherein Th_His is determined according to a following formula:

5. The method according to claim 1, wherein the scheduling the user in accordance with the determined priority and allocating the RB resources to the user is:

scheduling retransmission users in accordance with a priority order, wherein a number of RBs of each retransmission user depends on a retransmitted TB Size and is not limited by a GBR factor; and

scheduling new-transmission users in accordance with the priority order, and allocating RBs to each new-transmission user according to QoS determined by the GBR service of each new-transmission user, when there are remaining RB resources after all retransmission users are scheduled.

6. The method according to claim 5, wherein the allocating RBs to each new-transmission user according to the QoS determined by the GBR service of each new-transmission user is:

doing not schedule a new-transmission user, when determining that the average rate of the new-transmission user is greater than a Maximum Bit Rate (MBR);

determining a number of RBs for a new-transmission user according to a smaller value of the GBR and a Buffer Status Report (BSR) of the new-transmission user, when determining that the average rate of the new-transmission user is greater than or equal to the GBR but less than or equal to the MBR and further determining that there are other users with rates less than the GBR in a current cell;

determining a number of RBs for the new-transmission user according to a value in the BSR of the new-transmission user, when determining that the average rates of the other users in the current cell are greater than or equal to the GBR;

wherein the other users refer to all online users in the serving cell to which the new-transmission user belongs but excluding users just getting online in the current TTI, retransmission users, new-transmission users already scheduled prior to scheduling this new-transmission user, and this new-transmission user itself; and

determining a number of RBs for a new-transmission user according to the value in the BSR of the new-transmission user, when determining that the average rate of the new-transmission user is less than the GBR.

7. The method according to claim 6, further comprising:

when determining that the average rate of the new-transmission user is greater than or equal to the GBR but less than or equal to the MBR;

adding this user to a user list in which the number of RBs for the user is limited and the average rate of the user reaches the GBR, when the BSR of the user is greater than the GBR; and

allocating RB resources to the user in the user list of which the limited RB number has reached the GBR, when there are remaining RB resources after other users are all allocated with RB resources.

8. An apparatus for scheduling a Guaranteed Bit Rate (GBR) service based on Quality of Service (QoS), comprising a determining unit and a resource scheduling unit, wherein

the determining unit is configured to determine a scheduling priority of an online user according to an average rate of a GBR service of the user in a current Transmission Time Interval (TTI);

and

the resource scheduling unit is configured to schedule the user in accordance with the determined priority and allocate Resource Block (RB) resources to the user.

9. The apparatus according to claim 8, wherein the determining unit is further configured to determine the scheduling priority of the user according to a Proportional Fair (PF) scheduling algorithm in conjunction with QoS of the GBR service of the user.

10. The apparatus according to claim 9, wherein the determining unit is further configured to determine a scheduling priority Fair Factor (FF) of the user according to a following formula:

FF=FF_PF·

FF_GBR

where

11. The apparatus according to claim 10, wherein the determining unit is further configured to determine Th_His according to a following formula:

12. The apparatus according to claim 8, wherein the resource scheduling unit is further configured to:

schedule retransmission users in accordance with a priority order, wherein a number of RBs of each retransmission user depends on a retransmitted TB Size and is not limited by a GBR factor; and

schedule new-transmission users in accordance with the priority order, and allocate RBs to each new-transmission user according to QoS determined by the GBR service of each new-transmission user, when there are remaining RB resources after all retransmission users are scheduled.

13. The apparatus according to claim 12, wherein the resource scheduling unit is further configured to:

do not schedule a new-transmission user, when determining that the average rate of the new-transmission user is greater than a Maximum Bit Rate (MBR);

determine a number of RBs for a new-transmission user according to a smaller value of the GBR and a Buffer Status Report (BSR) of the new-transmission user, when determining that the average rate of the new-transmission user is greater than or equal to the GBR but less than or equal to the MBR and further determining that there are other users with rates less than the GBR in a current cell;

determine a number of RBs for the new-transmission user according to a value in the BSR of the new-transmission user, when determining that the average rates of the other users in the current cell are greater than or equal to the GBR;

wherein the other users refer to all online users in the serving cell to which the new-transmission user belongs but excluding users just getting online in the current TTI, retransmission users, new-transmission users already scheduled prior to scheduling this new-transmission user, and this new-transmission user itself; and

determine a number of RBs for a new-transmission user according to the value in the BSR of the new-transmission user, when determining that the average rate of the new-transmission user is less than the GBR.

14. The apparatus according to claim 13, wherein the resource scheduling unit is further configured to:

when determining that the average rate of the new-transmission user is greater than or equal to the GBR but less than or equal to the MBR, add this user to a user list in which the number of RBs for the user is limited and the average rate of the user reaches the GBR, when the BSR of the user is greater than the GBR; and

allocate RB resources to the user in the user list of which a limited RB number has reached the GBR, when there are remaining RB resources after other users are all allocated with RB resources.

15. The method according to claim 8, wherein the scheduling the user in accordance with the determined priority and allocating the RB resources to the user is:

scheduling retransmission users in accordance with a priority order, wherein a number of RBs of each retransmission user depends on a retransmitted TB Size and is not limited by a GBR factor; and

scheduling new-transmission users in accordance with the priority order, and allocating RBs to each new-transmission user according to QoS determined by the GBR service of each new-transmission user, when there are remaining RB resources after all retransmission users are scheduled.

16. The method according to claim 15, wherein the allocating RBs to each new-transmission user according to the QoS determined by the GBR service of each new-transmission user is:

doing not schedule a new-transmission user, when determining that the average rate of the new-transmission user is greater than a Maximum Bit Rate (MBR);

determining a number of RBs for a new-transmission user according to a smaller value of the GBR and a Buffer Status Report (BSR) of the new-transmission user, when determining that the average rate of the new-transmission user is greater than or equal to the GBR but less than or equal to the MBR and further determining that there are other users with rates less than the GBR in a current cell;

determining a number of RBs for the new-transmission user according to a value in the BSR of the new-transmission user, when determining that the average rates of the other users in the current cell are greater than or equal to the GBR;

wherein the other users refer to all online users in the serving cell to which the new-transmission user belongs but excluding users just getting online in the current TTI, retransmission users, new-transmission users already scheduled prior to scheduling this new-transmission user, and this new-transmission user itself; and

determining a number of RBs for a new-transmission user according to the value in the BSR of the new-transmission user, when determining that the average rate of the new-transmission user is less than the GBR.

17. The method according to claim 16, further comprising:

when determining that the average rate of the new-transmission user is greater than or equal to the GBR but less than or equal to the MBR;

adding this user to a user list in which the number of RBs for the user is limited and the average rate of the user reaches the GBR, when the BSR of the user is greater than the GBR; and

allocating RB resources to the user in the user list of which the limited RB number has reached the GBR, when there are remaining RB resources after other users are all allocated with RB resources.

18. The apparatus according to claim 11, wherein the resource scheduling unit is further configured to:

schedule retransmission users in accordance with a priority order, wherein a number of RBs of each retransmission user depends on a retransmitted TB Size and is not limited by a GBR factor; and

schedule new-transmission users in accordance with the priority order, and allocate RBs to each new-transmission user according to QoS determined by the GBR service of each new-transmission user, when there are remaining RB resources after all retransmission users are scheduled.

19. The apparatus according to claim 18, wherein the resource scheduling unit is further configured to:

do not schedule a new-transmission user, when determining that the average rate of the new-transmission user is greater than a Maximum Bit Rate (MBR);

determine a number of RBs for a new-transmission user according to a smaller value of the GBR and a Buffer Status Report (BSR) of the new-transmission user, when determining that the average rate of the new-transmission user is greater than or equal to the GBR but less than or equal to the MBR and further determining that there are other users with rates less than the GBR in a current cell;

determine a number of RBs for the new-transmission user according to a value in the BSR of the new-transmission user, when determining that the average rates of the other users in the current cell are greater than or equal to the GBR;

wherein the other users refer to all online users in the serving cell to which the new-transmission user belongs but excluding users just getting online in the current TTI, retransmission users, new-transmission users already scheduled prior to scheduling this new-transmission user, and this new-transmission user itself; and

determine a number of RBs for a new-transmission user according to the value in the BSR of the new-transmission user, when determining that the average rate of the new-transmission user is less than the GBR.

20. The apparatus according to claim 19, wherein the resource scheduling unit is further configured to:

when determining that the average rate of the new-transmission user is greater than or equal to the GBR but less than or equal to the MBR, add this user to a user list in which the number of RBs for the user is limited and the average rate of the user reaches the GBR, when the BSR of the user is greater than the GBR; and

allocate RB resources to the user in the user list of which a limited RB number has reached the GBR, when there are remaining RB resources after other users are all allocated with RB resources.