Management of dynamic transmission time interval scheduling for low latency communications

Patent metadata

Field	Value
Publication number	US-2016295584-A1
Application number	US-201615067554-A
Country	US
Kind code	A1
Filing date	Mar 11, 2016
Priority date	Mar 31, 2015
Publication date	Oct 6, 2016
Grant date	—

Abstract

Methods, systems, and devices for wireless communication are described. A wireless device may establish a configuration for at least one carrier based on multiple transmission time interval (TTI) lengths. Several TTI lengths may be associated in a TTI group, and aspects of the configuration may be the same for all TTIs having a TTI length in the TTI group. The device may then communicate using the carrier configuration based on the TTI group. In some cases, a second TTI group with different TTI lengths from the first group may also be identified, and the device may communicate using TTI from the second group using a different TTI group configuration. Aspects of a TTI group configuration may include a common control channel format, resource allocation granularity, hybrid automatic repeat request (HARQ) process, HARQ timing, soft buffer size, channel state information (CSI) reporting configuration, or an uplink control channel.

First claim

What is claimed is:

1 . A method of wireless communication, comprising:
identifying a carrier configuration comprising a plurality of transmission time interval (TTI) lengths; identifying a TTI group comprising two or more TTI lengths from the plurality of TTI lengths; and communicating using the carrier configuration and based at least in part on the identified TTI group.

2 . The method of claim 1 , further comprising:
identifying a second TTI group comprising one or more TTI lengths from the plurality of TTI lengths, wherein TTI lengths of each TTI group are different; and communicating using the carrier configuration and based at least in part on the second TTI group.

3 . The method of claim 1 , wherein the plurality of TTI lengths comprises at least one of a one symbol TTI length, a two symbol TTI length, a slot TTI length, or a subframe TTI length, or any combination thereof.

4 . The method of claim 1 , wherein communicating using the carrier configuration comprises:
communicating using a same control channel format for each TTI length in the TTI group.

5 . The method of claim 4 , wherein the control channel format comprises a field indicating a TTI length of a scheduled communication, and wherein the TTI length of the scheduled communication is selected from the TTI group.

6 . The method of claim 1 , further comprising:
communicating for a transport block using a first hybrid automatic repeat request (HARQ) transmission based at least in part on a first TTI length in the TTI group; and communicating for the transport block using a second HARQ transmission based at least in part on a second TTI length, different from the first TTI length, in the TTI group.

7 . The method of claim 1 , further comprising:
communicating an indication of a TTI group capability; and identifying the TTI group based at least in part on the indication of the TTI group capability.

8 . The method of claim 1 , further comprising:
identifying a TTI length for a scheduled communication based at least in part on the TTI group and a rank of the scheduled communication.

9 . The method of claim 1 , wherein identifying the carrier configuration comprises at least one of identifying a shared resource allocation granularity for the TTI group, identifying a shared hybrid automatic repeat request (HARQ) process for the TTI group, or identifying a shared HARQ timing based at least in part on the TTI group, or any combination thereof.

10 . The method of claim 1 , wherein the carrier configuration comprises a shared soft buffer for the TTI group.

11 . The method of claim 10 , wherein a size of the shared soft buffer is based at least in part on a longest TTI length in the TTI group.

12 . The method of claim 1 , wherein the carrier configuration comprises a shared channel state information (CSI) reporting configuration for the TTI group.

13 . The method of claim 12 , wherein the shared CSI reporting configuration is based at least in part on a shortest TTI length in the TTI group.

14 . The method of claim 1 , wherein at least one TTI length in the TTI group is associated with a limited number of initial symbol periods.

15 . The method of claim 1 , further comprising:
mapping each code block in a transport block to a first symbol of a TTI based at least in part on a TTI length from the TTI group, wherein the TTI length is greater than one symbol period.

16 . The method of claim 1 , wherein the TTI group is based at least in part on a user equipment (UE) capability, and wherein the UE capability is based at least in part on a low latency operation.

17 . An apparatus for wireless communication, comprising:
a processor; memory in electronic communication with the processor; and instructions stored in the memory and operable, when executed by the processor, to cause the apparatus to:
identify a carrier configuration comprising a plurality of transmission time interval (TTI) lengths;
identify a TTI group comprising two or more TTI lengths from the plurality of TTI lengths; and
communicate using the carrier configuration based at least in part on the identified TTI group.

18 . The apparatus of claim 17 , further comprising instructions to cause the apparatus to:
identify a second TTI group comprising one or more TTI lengths from the plurality of TTI lengths, wherein TTI lengths of each TTI group are different; and communicate using the carrier configuration and based at least in part on the second TTI group.

19 . The apparatus of claim 17 , wherein the plurality of TTI lengths comprises at least one of a one symbol TTI length, a two symbol TTI length, a slot TTI length, or a subframe TTI length, or any combination thereof.

20 . The apparatus of claim 17 , wherein the instructions to communicate using the carrier configuration comprise instructions to cause the apparatus to:
communicate using a same control channel format for each TTI length in the TTI group.

21 . The apparatus of claim 17 , further comprising instructions to cause the apparatus to:
communicate for a transport block using a first hybrid automatic repeat request (HARQ) transmission based at least in part on a first TTI length in the TTI group; and communicate for the transport block using a second HARQ transmission based at least in part on a second TTI length, different from the first TTI length, in the TTI group.

22 . The apparatus of claim 17 , further comprising instructions to cause the apparatus to:
communicate an indication of a TTI group capability; and identify the TTI group based at least in part on the indication of the TTI group capability.

23 . The apparatus of claim 17 , further comprising instructions to cause the apparatus to:
identify a TTI length for a scheduled communication based at least in part on the TTI group and a rank of the scheduled communication.

24 . The apparatus of claim 17 , wherein the instructions to identify the carrier configuration comprise at least one of instructions to identify a shared resource allocation granularity for the TTI group, instructions to identify a shared hybrid automatic repeat request (HARQ) process for the TTI group, or instructions to identify a shared HARQ timing based at least in part on the TTI group, or any combination thereof.

25 . The apparatus of claim 17 , wherein the carrier configuration comprises a shared soft buffer for the TTI group.

26 . The apparatus of claim 17 , wherein the carrier configuration comprises a shared channel state information (CSI) reporting configuration for the first TTI group.

27 . The apparatus of claim 17 , wherein at least one TTI length in the TTI group is associated with a limited number of initial symbol periods.

28 . The apparatus of claim 17 , further comprising instructions to cause the apparatus to:
map each code block in a transport block to a first symbol of a TTI based at least in part on a TTI length from the TTI group, wherein the TTI length is greater than one symbol period.

29 . An apparatus for wireless communication, comprising:
means for identifying a carrier configuration comprising a plurality of transmission time interval (TTI) lengths; means for identifying a TTI group comprising two or more TTI lengths from the plurality of TTI lengths; and means for communicating using the carrier configurati

Assignees

• Qualcomm Inc

Inventors

• Chen Wanshi
• Gaal Peter
• Patel Shimman Arvind
• Xu Hao
• Damnjanovic Aleksandar

Classifications

• H04L5/0048

  Allocation of pilot signals, i.e. of signals known to the receiver (allocation of control signalling H04L5/0053; use of control signalling H04L5/0091) · CPC title

• H04L5/0053 Primary

  Allocation of signalling, i.e. of overhead other than pilot signals · CPC title

• H04L5/001 Primary

  the frequencies being arranged in component carriers · CPC title

• H04W72/0446 Primary

  Resources in time domain, e.g. slots or frames · CPC title