TECHNIQUES AND APPARATUSES FOR WAVEFORM SIGNALING FOR DOWNLINK COMMUNICATIONS

• US 20180279292A1
• Filed: 10/05/2017
• Published: 09/27/2018
• Est. Priority Date: 03/23/2017
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: LUO, Tao, SUN, Jing, AKKARAKARAN, Sony, KADOUS, Tamer, WANG, Xiao feng, REDDY, Akula
• Granted Patent: US 10,667,244 B2
• Time in Patent Office: Days
• CPC Class Codes: H04B 7/00 Radio transmission systems, i.e. using radiation field H04B10/00, H04B15/00 take precedence
• CPC Class Codes: H04B 7/0452 Multi-user MIMO systems
• CPC Class Codes: H04L 1/0001 Systems modifying transmission characteristics according to link quality, e.g. power backoff adaptive data allocation for multicarrier modulation H04L5/0044; controlling transmission power for radio systems H04W52/04
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0025 Transmission of mode-switching indication
• CPC Class Codes: H04L 1/0028 Formatting
• CPC Class Codes: H04L 1/0039 other detection of signalling, e.g. detection of TFCI explicit signalling H04L1/0046, H04L27/0012 and H04L25/0262 take precedence
• CPC Class Codes: H04L 1/1854 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 1/1887 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• CPC Class Codes: H04L 5/0044 allocation of payload
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04L 5/0091 Signaling for the administration of the divided path
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal

Abstract

When a base station is capable of using multiple different types of waveforms for a downlink communication to a UE, the UE may waste processing resources attempting to receive and/or process the downlink communication. For example, the UE may cycle through various possible types of waveforms in an attempt to process the downlink communication. Techniques described herein use waveform signaling for downlink communications to notify the UE of a type of waveform being used for a downlink communication, thereby conserving UE resources (e.g., processing resources, memory resources, RF resources, and/or the like) that would otherwise be wasted attempting to process the downlink communication using multiple types of waveforms.

Claims

1. A method of wireless communication, comprising:

receiving, by a user equipment (UE), a waveform indication in a first downlink channel that uses a first waveform of a plurality of waveforms;

determining, by the UE, a second waveform, of the plurality of waveforms, to be used for one or more downlink communications in a second downlink channel based at least in part on the waveform indication received in the first downlink channel; and

processing, by the UE, the one or more downlink communications received in the second downlink channel using the second waveform.

2. The method of claim 1, wherein the first downlink channel is at least one of:

a first control channel, or

a broadcast channel; and

wherein the second downlink channel is at least one of;

a second control channel,

a data channel,

a unicast channel, or

a multicast channel.

3. The method of claim 1, wherein the waveform indication and the one or more downlink communications are received in a same transmission time interval.

4. The method of claim 1, wherein the first waveform is a default waveform used for the first downlink channel.

5. The method of claim 4, wherein the default waveform is determined based at least in part on:

a frequency band associated with the one or more downlink communications,

a system bandwidth, or

some combination thereof.

6. The method of claim 1, wherein the first waveform and the second waveform are different.

7. The method of claim 1, wherein the waveform indication includes a waveform identifier that explicitly identifies the second waveform.

8. The method of claim 1, wherein the waveform indication includes one or more configuration parameters that implicitly identify the second waveform.

9. The method of claim 8, wherein the one or more configuration parameters include one or more of:

a symbol duration for the one or more downlink communications,

a slot structure for the one or more downlink communications,

a bandwidth for the one or more downlink communications,

a frequency band for the one or more downlink communications,

a modulation or coding scheme for the one or more downlink communications, or

some combination thereof.

10. The method of claim 1, further comprising determining, based at least in part on the waveform indication, one or more configuration parameters associated with the one or more downlink communications.

11. The method of claim 10, wherein the one or more configuration parameters include one or more of:

a symbol duration for the one or more downlink communications,

a slot structure for the one or more downlink communications,

a bandwidth for the one or more downlink communications,

a frequency band for the one or more downlink communications,

a modulation or coding scheme for the one or more downlink communications, or

some combination thereof.

12. The method of claim 1, wherein the plurality of waveforms include a discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-s-OFDM) waveform and a cyclic prefix orthogonal frequency division multiplexing (CP-OFDM) waveform.

13. The method of claim 12, wherein at least one of a reference signal or a data tone is received using pre-DFT-spread multiplexing or time division multiplexing when the second waveform is the DFT-s-OFDM waveform, or

wherein at least one of a reference signal or a data tone is received using frequency division multiplexing (FDM) or time division multiplexing when the second waveform is the CP-OFDM waveform.

14. The method of claim 1, wherein the one or more downlink communications are processed using interference cancellation based at least in part on an indication of a waveform, of the plurality of waveforms, associated with downlink communications of another UE.

15. A method of wireless communication, comprising:

receiving, by a first user equipment (UE), a first indication of a first waveform, of a plurality of waveforms, to be used for one or more downlink communications associated with the first UE;

receiving, by the first UE, a second indication of a second waveform, of the plurality of waveforms, associated with downlink communications of a second UE;

receiving, by the first UE, the one or more downlink communications using the first waveform; and

processing, by the first UE, the one or more downlink communications based at least in part on the second indication of the second waveform.

16. The method of claim 15, wherein the one or more downlink communications are processed using interference cancellation based at least in part on the second indication of the second waveform associated with the downlink communications of the second UE.

17. The method of claim 15, wherein the first indication includes a layer identifier associated with a multi-user multiple-input and multiple-output communication.

18. A method of wireless communication, comprising:

generating, by a base station, a first transmission layer of a multi-layer communication using a first waveform of a plurality of waveforms;

generating, by the base station, a second transmission layer of the multi-layer communication using a second waveform of the plurality of waveforms, wherein the first waveform and the second waveform are different; and

transmitting, by the base station, the first transmission layer and the second transmission layer using a same time resource and a same frequency resource, wherein the first transmission layer is transmitted using the first waveform and the second transmission layer is transmitted using the second waveform.

19. The method of claim 18, wherein the first transmission layer is transmitted to a first user equipment (UE) and the second transmission layer is transmitted to a second UE.

20. The method of claim 19, further comprising transmitting at least one of:

an indication of the first waveform to the second UE, or

an indication of the second waveform to the first UE.

21. The method of claim 19, wherein the first transmission layer and the second transmission layer are transmitted using different antenna beams of the base station.

22. A user equipment (UE) for wireless communication, comprising:

memory; and

one or more processors coupled to the memory, the memory and the one or more processors configured to;

receive a waveform indication in a first downlink channel that uses a first waveform of a plurality of waveforms;

determine a second waveform, of the plurality of waveforms, to be used for one or more downlink communications in a second downlink channel based at least in part on the waveform indication received in the first downlink channel; and

process the one or more downlink communications received in the second downlink channel using the second waveform.

23. The UE of claim 22, wherein the first downlink channel is at least one of:

a first control channel, or

a broadcast channel; and

wherein the second downlink channel is at least one of;

a second control channel,

a data channel,

a unicast channel, or

a multicast channel.

24. The UE of claim 22, wherein the waveform indication and the one or more downlink communications are received in a same transmission time interval.

25. The UE of claim 22, wherein the first waveform is a default waveform used for the first downlink channel, wherein the default waveform is determined based at least in part on:

a frequency band associated with the one or more downlink communications,

a system bandwidth, or

some combination thereof.

26. The UE of claim 22, wherein the first waveform and the second waveform are different.

27. The UE of claim 22, wherein the waveform indication includes at least one of:

a waveform identifier that explicitly identifies the second waveform, or

one or more configuration parameters that implicitly identify the second waveform, wherein the one or more configuration parameters include one or more of;

a symbol duration for the one or more downlink communications,

a slot structure for the one or more downlink communications,

a bandwidth for the one or more downlink communications,

a frequency band for the one or more downlink communications,

a modulation or coding scheme for the one or more downlink communications, or

some combination thereof.

28. The UE of claim 22, wherein the one or more processors are further configured to determine, based at least in part on the waveform indication, one or more configuration parameters associated with the one or more downlink communications, wherein the one or more configuration parameters include one or more of:

a symbol duration for the one or more downlink communications,

a slot structure for the one or more downlink communications,

a bandwidth for the one or more downlink communications,

a frequency band for the one or more downlink communications,

a modulation or coding scheme for the one or more downlink communications, or

some combination thereof.

29. The UE of claim 22, wherein the plurality of waveforms include a discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-s-OFDM) waveform and a cyclic prefix orthogonal frequency division multiplexing (CP-OFDM) waveform.

30. The UE of claim 22, wherein the one or more downlink communications are processed using interference cancellation based at least in part on an indication of a waveform, of the plurality of waveforms, associated with downlink communications of another UE.