METHOD AND APPARATUS FOR LOGICAL CHANNEL PRIORITIZATION FOR UPLINK CARRIER AGGREGATION

• US 20110170495A1
• Filed: 01/08/2010
• Published: 07/14/2011
• Est. Priority Date: 01/08/2010
• Status: Active Grant

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: Blackberry Limited
• Inventors: Cal, Zhijun, Xu, Hua, Earnshaw, Mark, Heo, Youn Hyoung, Fong, Mo-Han
• Granted Patent: US 8,638,815 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/0058 Allocation criteria
• CPC Class Codes: H04L 5/0091 Signaling for the administration of the divided path
• CPC Class Codes: H04W 72/02 Selection of wireless resources by user or terminal

Abstract

A method and apparatus for logical channel prioritization at a user equipment in a multiple uplink carrier system, the method receiving a set of logical channel priorities at the user equipment, the logical channel priorities being assigned on a per carrier basis; and applying the set of logical channel priorities to each logical channel for carrier selection. Further a method and apparatus for constructing an uplink medium access control protocol data unit at a user equipment in a multiple uplink carrier system, the method sorting possible logical channel and carrier pairings based on logical channel priorities; utilizing a prioritized bit rate process to allocate logical channel traffic in an order determined by the sorting; and performing a remaining resources process to allocate logical channel traffic based on a priority order.

Claims

1. A method for logical channel prioritization at a user equipment in a system supporting multiple uplink carriers comprising:

receiving a set of logical channel priorities at the user equipment, said logical channel priorities being assigned on a per carrier basis; and

applying the set of logical channel priorities to each logical channel for carrier selection.

2. The method of claim 1, wherein the logical channel priorities are further assigned on a per carrier group basis.

3. The method of claim 1, wherein the logical channel priorities include a setting preventing a logical channel from transmitting on an uplink carrier.

4. The method of claim 1, wherein the applying applies a potentially different priority for each carrier to each logical channel.

5. The method of claim 1, wherein the logical channel priorities are applicable uniformly to all uplink carriers.

6. The method of claim 1, wherein the receiving is performed semi-statically through radio resource control signaling.

7. The method of claim 1, wherein the logical channel priorities are grouped into sets.

8. The method of claim 7, wherein the sets are configured utilizing radio resource control signaling.

9. The method of claim 7, wherein the receiving is performed utilizing medium access control (“

MAC”

) control elements.

10. The method of claim 9, wherein a field value in a control element is associated with a carrier and a logical channel priority set.

11. The method of claim 7, wherein the receiving is performed utilizing downlink control information.

12. The method of claim 11, wherein the downlink control information includes a field value corresponding with a logical channel priority set to be used for a carrier associated with the downlink control information.

13. The method of claim 1, wherein the applying ensures at least one carrier is available to a logical channel for uplink transmission.

14. A user equipment comprising:

a communications subsystem; and

a processor,

the communications subsystem and processor cooperating to;

receive a set of logical channel priorities at the user equipment, said logical channel priorities being assigned on a per carrier basis; and

apply the set of logical channel priorities to each logical channel for carrier selection.

15. A method for constructing an uplink medium access control protocol data unit at a user equipment in a multiple uplink carrier system comprising:

receiving multiple uplink grants;

sorting the multiple uplink grants from a highest priority grant to a lowest priority grant; and

applying a logical channel prioritization scheme sequentially for the grants using logical channel priorities to allocate logical channel traffic to the medium access control protocol data unit.

16. The method of claim 15, wherein the sorting utilizes tie breaking rules for uplink grants for carriers having a same relative priority.

17. The method of claim 16, wherein the tie breaking rules are selected from the group consisting of:

assigning a higher priority for larger uplink grants than smaller uplink grants;

assigning a higher priority for smaller uplink grants than larger uplink grants; and

pseudo-randomly determining a higher priority for carriers having a same relative priority.

18. A user equipment comprising:

a communications subsystem; and

a processor,

the communications subsystem and processor cooperating to;

receive multiple uplink grants;

sort the multiple uplink grants from a highest priority grant to a lowest priority grant; and

apply a logical channel prioritization scheme sequentially for the grants using logical channel priorities to allocate logical channel traffic to the medium access control protocol data unit.

19. A method for constructing an uplink medium access control protocol data unit at a user equipment in a multiple uplink carrier system comprising:

sorting possible logical channel and carrier pairings based on logical channel priorities;

utilizing a prioritized bit rate process to allocate logical channel traffic in an order determined by the sorting; and

performing a remaining resources process to allocate logical channel traffic based on a priority order.

20. The method of claim 19, wherein the sorting includes tie breaking rules for logical channel and carrier pairings having the same priority.

21. The method of claim 20, wherein the tie breaking rules are selected from the group consisting of:

prioritizing a carrier with a larger grant;

prioritizing carriers that have forbidden logical channels;

semi-statically configuring carrier order; and

breaking ties randomly.

22. The method of claim 19, wherein the prioritized bit rate process utilizes a token bucket scheduler to determine carrier and logical channel allocation.

23. The method of claim 19, further comprising a further arranging step prior to the performing of the remaining resources process, wherein the arranging utilizes different tie breaking rules from the sorting step.

24. The method of claim 23, wherein the tie breaking rules for the sorting are selected from the group consisting of:

prioritizing a carrier whose grant has less remaining space than grants on other carriers but whose remaining space is greater than a bucket content for a logical channel; and

prioritizing a carrier whose potential traffic for all logical channels not forbidden from transmitting over the carrier is the least.

25. The method of claim 23, wherein the tie breaking rules for the arranging include choosing a grant that already has a resource assignment for a current logical channel.

26. The method of claim 19, wherein the utilizing further comprises reserving resources on a plurality of carriers having the same priority for a logical channel until other logical channels have filled grants for all but one of the plurality of carriers.

27. A user equipment comprising:

a communications subsystem; and

a processor,

the communications subsystem and processor cooperating to;

sort possible logical channel and carrier pairings based on logical channel priorities;

utilize a prioritized bit rate process to allocate logical channel traffic in an order determined by the sorting; and

perform a remaining resources process to allocate logical channel traffic based on a priority order.

28. A method for transmitting an uplink medium access control (“

MAC”

) control element from a user equipment in a multiple uplink carrier system, comprising;

choosing at least one carrier from the multiple uplink carriers to transmit the MAC control element.

29. The method of claim 28, wherein the choosing utilizes a carrier subset selected from the group consisting of:

a single reference carrier for transmitting the MAC control element;

a reference carrier for transmitting the MAC control element if a grant for the reference carrier is received in a subframe, and utilizes another carrier having a grant in the subframe otherwise;

a carrier that does not originate from a semi-persistent scheduling uplink grant for transmitting the MAC control element;

a different carrier on each transmission opportunity;

at least one uplink carrier with a grant in a current subframe;

a carrier associated with a carrier specific MAC control element to transmit the MAC control element; and

a virtual uplink carrier communicating with an evolved Node B scheduling a carrier the MAC control element is associated with.

30. A network element comprising:

a communications subsystem; and

a processor,

the communications subsystem and processor cooperating to;

assign a set of logical channel priorities for a user equipment, said logical channel priorities being assigned on a per carrier basis; and

transmit the logical channel priorities to the user equipment.