Cross-carrier scheduling for wireless devices

• US 10,448,421 B2
• Filed: 09/28/2017
• Issued: 10/15/2019
• Est. Priority Date: 03/20/2017
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Bhattad, Kapil, Rico Alvarino, Alberto, Xu, Hao
• Primary Examiner(s): Huq, Obaidul
• Application Number:
  US15/719,030
• Publication Number:
  US 20180270851A1
• Time in Patent Office: 747 Days
• Field of Search: 370310, 370328, 370329
• CPC Class Codes: H04L 1/1812 Hybrid protocols; Hybrid automatic repeat request [HARQ]
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/1268 of uplink data flows
• CPC Class Codes: H04W 72/1273 of downlink data flows
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 72/569 of the traffic information

Abstract

Methods, systems, and devices for wireless communication are described for cross-carrier scheduling for wireless devices. In an example, a wireless device may monitor a control channel on a first carrier of a plurality of carriers to obtain a grant allocating resources to the wireless device within a shared data channel. In some cases, a time duration between the grant and the allocated resources within the shared data channel is based at least in part on which carrier of the plurality of carriers transports the shared data channel. The wireless device may transmit or receive over the shared data channel using the allocated resources and based at least in part on the time duration.

Claims

1. A method for wireless communication, comprising:

monitoring, by a wireless device, a control channel on a first carrier of a plurality of carriers to obtain a grant allocating resources to the wireless device within a shared data channel, wherein a time duration between the grant and the allocated resources within the shared data channel is based at least in part on whether the first carrier or a second carrier of the plurality of carriers transports the shared data channel, the first carrier differing from the second carrier; and

transmitting or receiving over the shared data channel using the allocated resources and based at least in part on the time duration.

2. The method of claim 1, wherein the time duration includes an added amount of time and a defined amount of time based at least in part on the transmitting or receiving occurring via the second carrier.

3. The method of claim 1, wherein, when multiple Hybrid Automatic Repeat reQuest (HARQ) processes are enabled, the time duration includes an amount of time to enable the wireless device to receive a second instance of the control channel on the first carrier or the second carrier of the plurality of carriers prior to the transmitting or receiving over the shared data channel using the allocated resources.

4. The method of claim 3, wherein the time duration includes an amount of time between the second instance of the control channel and a beginning of the allocated resources.

5. The method of claim 3, further comprising:

receiving a second grant within the second instance of the control channel, the second grant allocating second resources within the shared data channel at a time different than a time of the allocated resources.

6. The method of claim 5, further comprising:

determining, based at least in part on first and second carrier indices, that the allocated resources and the second allocated resources are not allocated on a same carrier of the plurality of carriers, wherein a time gap between a timing of the allocated resources and a timing of the second allocated resources is based at least in part on the allocated resources and the second allocated resources not being on a same carrier.

7. The method of claim 5, further comprising:

determining, based at least in part on first and second carrier indices, that a carrier of the plurality of carriers for a first uplink transmission differs from a carrier of the plurality of carriers for a second uplink transmission, wherein a time gap between a timing of the first uplink transmission and a timing of the second uplink transmission is based at least in part on the carrier for the first uplink transmission differing from the carrier for the second uplink transmission.

8. The method of claim 1, wherein, when Hybrid Automatic Repeat reQuest (HARQ) with multiple HARQ processes is enabled, the time duration includes an amount of time to enable the wireless device to receive a second instance of the control channel on the first carrier or the second carrier of the plurality of carriers prior to the transmitting or receiving over the shared data channel using the allocated resources, the method further comprising:

receiving a second grant within the second instance of the control channel, the second grant allocating second resources within the shared data channel at a time different than a time of the allocated resources, the second allocated resources and the allocated resources being on a same carrier.

9. The method of claim 1, further comprising:

monitoring, by the wireless device, for a reference signal on a carrier of the plurality of carriers within a time interval that includes a first defined amount of time prior to a beginning of a scheduled transmission to the wireless device on the carrier and a second defined amount of time after an end of the scheduled transmission; and

refraining from monitoring the carrier for the reference signal outside of the time interval.

10. The method of claim 1, wherein the time duration is an amount of time, a number of subframes, or both.

11. The method of claim 1, wherein the time duration is based at least in part on whether Hybrid Automatic Repeat reQuest (HARQ) is enabled, whether the grant is for uplink or downlink, whether the grant is received in a first or second instance of the control channel, whether cross-carrier scheduling is enabled, or any combination thereof.

12. A method for wireless communication, comprising:

determining a time duration relative to a control channel of when to allocate resources to a wireless device, wherein the time duration is based at least in part on whether a first carrier or a second carrier of a plurality of carriers transports a shared data channel, the first carrier differing from the second carrier; and

transmitting a grant in the control channel to the wireless device identifying a timing of the allocated resources within the shared data channel, the timing of the allocated resources being based at least in part on the time duration.

13. The method of claim 12, wherein the time duration includes an amount of time based at least in part on the control channel being transported on the first carrier of the plurality of carriers and the shared data channel being transported on the second carrier of the plurality of carriers.

14. The method of claim 12, wherein the time duration enables the wireless device to receive a second instance of the control channel prior to transmitting or receiving over the shared data channel using the allocated resources.

15. The method of claim 14, wherein the time duration includes an amount of time between the second instance of the control channel and a beginning of the allocated resources.

16. The method of claim 14, further comprising:

transmitting a second grant within the second instance of the control channel, the second grant allocating second resources within the shared data channel at a time different than a time of the allocated resources.

17. The method of claim 12, further comprising:

identifying an amount of time prior to a beginning of a scheduled transmission to the wireless device on a carrier of the plurality of carriers and after an ending of the scheduled transmission to the wireless device on the carrier;

transmitting a reference signal one or more times on the carrier within the identified amount of time;

determining that no additional transmissions have been scheduled on the carrier prior to and after the identified amount of time; and

refraining from transmitting the reference signal on the carrier outside of the identified amount of time.

18. The method of claim 12, wherein the grant includes the time duration.

19. The method of claim 12, further comprising:

signaling the time duration to the wireless device during a connection setup, a connection reconfiguration, or both.

20. The method of claim 12, wherein the grant allocates second resources within the shared data channel at a time different than a time of the allocated resources.

21. The method of claim 12, wherein the time duration is based at least in part on whether Hybrid Automatic Repeat reQuest (HARQ) is enabled, whether the grant is for uplink or downlink, whether the grant is received in a first or second instance of the control channel, whether cross-carrier scheduling is enabled, or any combination thereof.

22. An apparatus for wireless communication, in a system comprising:

a processor;

memory coupled with the processor; and

instructions stored in the memory and operable, when executed by the processor, to cause the apparatus to;

monitor a control channel on a first carrier of a plurality of carriers to obtain a grant allocating resources to a wireless device within a shared data channel, wherein a time duration between the grant and the allocated resources within the shared data channel is based at least in part on whether a first carrier or a second carrier of the plurality of carriers transports the shared data channel, the first carrier differing from the second carrier; and

transmit or receive over the shared data channel using the allocated resources and based at least in part on the time duration.

23. The apparatus of claim 22, wherein monitoring the control channel comprises further instructions executable by the processor to:

determine, based at least in part on the grant, that the shared data channel is transported on the second carrier of the plurality of carriers, and wherein the time duration includes an added amount of time and a defined amount of time based at least in part on transmitting or receiving over the shared data channel occurring via the second carrier.

24. The apparatus of claim 22, wherein, when Hybrid Automatic Repeat reQuest (HARQ) is enabled, the time duration includes an amount of time to enable the wireless device to receive a second instance of the control channel on the first carrier or the second carrier of the plurality of carriers prior to the transmitting or receiving over the shared data channel using the allocated resources.

25. The apparatus of claim 22, wherein the instructions are further executable by the processor to:

monitor for a reference signal on a carrier of the plurality of carriers within a time interval that includes a first defined amount of time prior to a beginning of a scheduled transmission to the wireless device on the carrier and a second defined amount of time after an end of the scheduled transmission; and

refrain from monitoring the carrier for the reference signal outside of the time interval.

26. The apparatus of claim 22, wherein the time duration is based at least in part on whether Hybrid Automatic Repeat reQuest (HARQ) is enabled, whether the grant is for uplink or downlink, whether the grant is received in a first or second instance of the control channel, whether cross-carrier scheduling is enabled, or any combination thereof.

27. An apparatus for wireless communication, in a system comprising:

a processor;

memory coupled with the processor; and

instructions stored in the memory and operable, when executed by the processor, to cause the apparatus to;

determine a time duration relative to a control channel of when to allocate resources to a wireless device, wherein the time duration is based at least in part on whether a first carrier or a second carrier of a plurality of carriers transports a shared data channel, the first carrier differing from the second carrier; and

transmit a grant in the control channel to the wireless device identifying a timing of the allocated resources within the shared data channel, the timing of the allocated resources being based at least in part on the time duration.

28. The apparatus of claim 27, wherein the time duration includes an amount of time based at least in part on the control channel being transported on the first carrier of the plurality of carriers and the shared data channel being transported on the second carrier of the plurality of carriers.

29. The apparatus of claim 27, wherein the time duration enables the wireless device to receive a second instance of the control channel prior to transmitting or receiving over the shared data channel using the allocated resources, and wherein the instructions are further executable by the processor to:

transmit a second grant within the second instance of the control channel, the second grant allocating second resources within the shared data channel at a time different than a time of the allocated resources.

30. The apparatus of claim 27, wherein the instructions are further executable by the processor to:

identify an amount of time prior to a beginning of a scheduled transmission to the wireless device on a carrier of the plurality of carriers and after an ending of the scheduled transmission to the wireless device on the carrier;

transmit a reference signal one or more times on the carrier within the identified amount of time;

determine that no additional transmissions have been scheduled on the carrier prior to and after the identified amount of time; and

refrain from transmitting the reference signal on the carrier outside of the identified amount of time.