TECHNIQUES FOR AGGREGATING DATA FROM WWAN AND WLAN

• US 20150117357A1
• Filed: 08/08/2014
• Published: 04/30/2015
• Est. Priority Date: 10/30/2013
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: OZTURK, Ozcan, HORN, Gavin Bernard, VAJAPEYAM, Madhavan Srinivasan, DAMNJANOVIC, Jelena, WEI, Yongbin
• Granted Patent: US 9,585,048 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04L 1/1628 List acknowledgements, i.e. the acknowledgement message consisting of a list of identifiers, e.g. of sequence numbers H04L1/1614 takes precedence
• CPC Class Codes: H04L 1/1685 the supervisory signal being transmitted in response to a specific request, e.g. to a polling signal
• CPC Class Codes: H04L 47/34 ensuring sequence integrity, e.g. using sequence numbers
• CPC Class Codes: H04L 47/41 by acting on aggregated flows or links
• CPC Class Codes: H04L 49/9057 Arrangements for supporting packet reassembly or resequencing
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports
• CPC Class Codes: H04W 28/0205 at the air interface dynamic wireless traffic scheduling H04W72/12
• CPC Class Codes: H04W 80/02 Data link layer protocols
• CPC Class Codes: H04W 84/042 Public Land Mobile systems, e.g. cellular systems
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals
• CPC Class Codes: H04W 88/10 adapted for operation in multiple networks, e.g. multi-mode access points

Abstract

Certain aspects of the present disclosure relate to techniques for aggregating data from a wireless wide area network (WWAN) and wireless local area network (WLAN). In some aspects, a packet convergence entity (e.g., PDCP layer entity) communicates with first and second radio access technology (RAT) links. The packet convergence entity may determine from which of the first and second RAT links a data packet is received and may monitor a sequence number value of each of the received data packets. The packet convergence entity may perform one or more actions based on a determination that the data packets are received out of order. For example, the packet convergence entity may deliver the data packets to an upper layer entity as they are received (e.g., in order or out of order), may reorder the data packets and ignore data packet losses, and/or may request retransmissions of missing data packets.

Claims

1. A method for aggregating data in wireless communications, the method comprising:

communicating data packets, by a packet convergence entity, with a first radio access technology (RAT) link and a second RAT link;

determining whether each of the data packets is received from the first RAT link and the second RAT link;

monitoring a sequence number value of each of the data packets received on the first RAT link and the second RAT link;

determining whether the sequence number values of the data packets received on the first RAT link and the second RAT link are out of order;

performing one or more actions based at least in part on the determination that the sequence number values of the received data packets are out of order; and

exchanging packet status information in response to one or more events on one or both of the first RAT link and the second RAT link.

2. The method of claim 1, wherein:

the first RAT link comprises a wireless wide area network (WWAN) link,

the second RAT link comprises a wireless local area network (WLAN) link, and

the packet convergence entity comprises a packet data convergence protocol (PDCP) entity.

3. The method of claim 2, wherein:

the WWAN link comprises a Long Term Evolution (LTE) link or a Universal Mobile Telecommunication System (UMTS) link, and

the WLAN link comprises a Wi-Fi link.

4. The method of claim 1, wherein the one or more actions comprise sending a current one of the data packets by the packet convergence entity to an upper layer entity when a packet reordering timer is currently not running and when the sequence number (SN) value of the current received packet is less than or equal to an expected SN value, wherein the expected SN value is one more than a largest SN value of a data packet delivered to the upper layer entity.

5. The method of claim 1, wherein the one or more actions comprise starting a packet reordering timer if it is not running when a data packet with an SN value greater than an expected SN value is received by the packet convergence entity, wherein the expected SN value is one more than a largest SN value of a data packet delivered to an upper layer entity.

6. The method of claim 5, wherein the one or more actions comprise stopping the packet reordering timer when a predefined time is reached.

7. The method of claim 1, wherein the one or more actions comprise stopping a packet reordering timer when both the first and second RAT links are configured to deliver data packets in ascending order of SN values, and when a minimum value of the SNs received on each link is greater than or equal to an SN value of a data packet that when received started the packet reordering timer.

8. The method of claim 1, wherein the one or more actions comprise sending at least a portion of the data packets received by the packet convergence entity to an upper layer entity, the at least a portion of the data packets comprising those data packets with an SN value that is less than an SN value of a data packet that when received started a packet reordering timer that is now stopped.

9. The method of claim 1, wherein the one or more actions comprise sending at least a portion of the data packets received by the packet convergence entity to an upper layer entity, the at least a portion of the data packets comprising those data packets with an SN value less than or equal to an upper bound and greater than or equal to an SN value of a data packet that when received started a packet reordering timer that is now stopped.

10. The method of claim 9, wherein the upper bound is one of:

a largest SN value of the data packet received in SN value order after the data packet that when received started the packet reordering timer that is now stopped,

a largest SN value of the data packets received after the data packet that when received started the packet reordering timer that is now stopped, and

a minimum of a largest SN value of the data packets received on the first RAT link and a largest SN value of the data packets received on the second RAT link after the data packet that when received started the packet reordering timer that is now stopped.

11. The method of claim 1, further comprising receiving an indication from each of the first and second RAT links to enable the packet convergence entity to identify from which of the first and second RAT links is a data packet received by the packet convergence entity.

12. The method of claim 1, further comprising sending a packet convergence entity status report from the packet convergence entity to request retransmission of one or more data packets determined missing.

13. The method of claim 1, further comprising periodically sending a packet convergence entity status report from the packet convergence entity.

14. The method of claim 1, further comprising:

receiving a status request from a transmitter of the data packets; and

sending a packet convergence entity status report for the data packets received and for data packets determined to be missing in response to the status request.

15. An apparatus for aggregating data in wireless communications, the apparatus comprising:

means for communicating data packets, by a packet convergence entity, with a first radio access technology (RAT) link and a second RAT link;

means for determining whether each of the data packets is received from the first RAT link and the second RAT link;

means for monitoring a sequence number value of each of the data packets received on the first RAT link and the second RAT link;

means for determining whether the sequence number values of the data packets received on the first RAT link and the second RAT link are out of order;

means for performing one or more actions based at least in part on the determination that the sequence number values of the received data packets are out of order; and

means for exchanging packet status information in response to one or more events on one or both of the first RAT link and the second RAT link.

16. A network device for aggregating data in wireless communications, comprising:

a receiver component configured to communicate data packets, by a packet convergence entity, with a first radio access technology (RAT) link and a second RAT link;

an identifier component configured to determine whether each of the data packets is received from the first RAT link and the second RAT link;

a monitoring component configured to monitor a sequence number value of each of the data packets received on the first RAT link and the second RAT link, wherein the monitoring component is further configured to determine whether the sequence number values of the data packets received on the first RAT link and the second RAT link are out of order;

a reordering component configured to perform one or more actions based at least in part on the determination that the sequence number values of the received data packets are out of order; and

a status component configured to exchange packet status information in response to one or more events on one or both of first RAT link and the second RAT link.

17. The network device of claim 16, wherein:

the first RAT link comprises a wireless wide area network (WWAN) link,

the second RAT link comprises a wireless local area network (WLAN) link, and

the packet convergence entity comprises a packet data convergence protocol (PDCP) entity.

18. The network device of claim 17, wherein:

the WWAN link comprises a Long Term Evolution (LTE) link or a Universal Mobile Telecommunication System (UMTS) link, and

the WLAN link comprises a Wi-Fi link.

19. The network device of claim 16, further comprising a packet reordering timer, wherein the one or more actions comprise sending a current one of the data packets by the packet convergence entity to an upper layer entity when the packet reordering timer is currently not running and when the sequence number (SN) value of the current received packet is less than or equal to an expected SN value, and wherein the expected SN value is one more than a largest SN value of a data packet delivered to the upper layer entity.

20. The network device of claim 16, further comprising a packet reordering timer, wherein the one or more actions comprise starting the packet reordering timer if it is not running when a data packet with an SN value greater than an expected SN value is received by the packet convergence entity, and wherein the expected SN value is one more than a largest SN value of a data packet delivered to an upper layer entity.

21. The network device of claim 20, wherein the one or more actions comprise stopping the packet reordering timer when a predefined time is reached.

22. The network device of claim 16, further comprising a packet reordering timer, wherein the one or more actions comprise stopping the packet reordering timer when both the first and second RAT links are configured to deliver data packets in ascending order of SN values, and when a minimum value of the SNs received on each link is greater than or equal to an SN value of a data packet that when received started the packet reordering timer.

23. The network device of claim 16, further comprising a packet reordering timer, wherein the one or more actions comprise sending at least a portion of the data packets received by the packet convergence entity to an upper layer entity, the at least a portion of the data packets comprising those data packets with an SN value that is less than an SN value of a data packet that when received started the packet reordering timer that is now stopped.

24. The network device of claim 16, further comprising a packet reordering timer, wherein the one or more actions comprise sending at least a portion of the data packets received by the packet convergence entity to an upper layer entity, the at least a portion of the data packets comprising those data packets with an SN value less than or equal to an upper bound and greater than or equal to an SN value of a data packet that when received started the packet reordering timer that is now stopped.

25. The network device of claim 24, wherein the upper bound is one of:

a largest SN value of the data packet received in SN value order after the data packet that when received started the packet reordering timer that is now stopped,

a largest SN value of the data packets received after the data packet that when received started the packet reordering timer that is now stopped, and

a minimum of a largest SN value of the data packets received on the first RAT link and a largest SN value of the data packets received on the second RAT link after the data packet that when received started the packet reordering timer that is now stopped.

26. A method for aggregating data in wireless communications, the method comprising:

transmitting data packets to a wireless communications device through a first radio access technology (RAT) link and a second RAT link, wherein each of the data packets has an assigned sequence number (SN) value for packet aggregation at a packet convergence entity within the wireless communications device; and

performing flow control over the first and second RAT links, the flow control being configured to prevent one or both of underflow and overflow of buffers for each of the first and second RAT links.

27. The method of claim 26, wherein:

the first RAT link comprises a wireless wide area network (WWAN) link,

the second RAT link comprises a wireless local area network (WLAN) link, and

the packet convergence entity comprises a packet data convergence protocol (PDCP) entity.

28. The method of claim 27, wherein:

the WWAN link comprises a Long Term Evolution (LTE) link or a Universal Mobile Telecommunication System (UMTS) link, and

the WLAN link comprises a Wi-Fi link.

29. The method of claim 26, further comprising assigning a first in-order sequence of SN values to the data packets transmitted through the first RAT link and a second in-order sequence of SN values to the data packets transmitted through the second RAT link.

30. The method of claim 26, further comprising:

receiving a status report request from the packet convergence entity when the packet convergence entity determines that a data packet is missing from whichever of the first and second RAT links provides in-sequence delivery or when the packet convergence entity determines that transmission performance on either of the first and second RAT links is less than a threshold value; and

transmitting a status report to the wireless communications device in response to the status report request.