METHOD AND APPARATUS FOR SCHEDULING USER EQUIPMENT UPLINK TRANSMISSIONS ON AN UNLICENSED CARRIER

• US 20160278049A1
• Filed: 06/26/2015
• Published: 09/22/2016
• Est. Priority Date: 03/17/2015
• Status: Active Grant

• Current Assignee: Motorola Mobility LLC (Lenovo Group Ltd.)
• Original Assignee: Motorola Mobility LLC (Lenovo Group Ltd.)
• Inventors: Nory, Ravikiran, Nangia, Vijay, Narasimha, Murali, Nimbalker, Ajit
• Granted Patent: US 9,781,712 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04L 1/1812 Hybrid protocols; Hybrid automatic repeat request [HARQ]
• CPC Class Codes: H04L 1/1896 ARQ related signaling
• CPC Class Codes: H04L 27/0006 Assessment of spectral gaps suitable for allocating digitally modulated signals, e.g. for carrier allocation in cognitive radio for spectrum sharing between different networks H04W16/14
• CPC Class Codes: H04L 5/0044 allocation of payload
• CPC Class Codes: H04L 5/0051 of dedicated pilots, i.e. pilots destined for a single user or terminal
• CPC Class Codes: H04L 5/0055 Physical resource allocation for ACK/NACK for physical mapping arrangements in ARQ protocols H04L1/1861
• CPC Class Codes: H04L 5/0091 Signaling for the administration of the divided path
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal

Abstract

A method and apparatus schedule user equipment uplink transmissions on an unlicensed carrier. A grant for transmitting physical uplink shared channel on a serving cell operating on an unlicensed carrier can be received in a subframe. A set of subframes can be determined for possible transmission of the physical uplink shared channel. Listen before talk can be performed on the unlicensed carrier to determine an earliest unoccupied subframe in the set of subframes. A physical uplink shared channel can be transmitted in multiple subframes within the set of subframes on the unlicensed carrier, starting with the earliest unoccupied subframe, in response to receiving the grant.

Claims

1. A method in a user equipment, the method comprising:

receiving, in a subframe, a grant for transmitting physical uplink shared channel on a serving cell operating on an unlicensed carrier;

determining a set of subframes for possible transmission of the physical uplink shared channel;

performing listen before talk on the unlicensed carrier to determine an earliest unoccupied subframe in the set of subframes; and

transmitting physical uplink shared channel transmissions in multiple subframes within the set of subframes on the unlicensed carrier, starting with the earliest unoccupied subframe, in response to receiving the grant.

2. The method according to claim 1,

wherein the grant includes a parameter indicating a window length, and

wherein determining a set of subframes comprises determining the set of subframes for possible transmission of the physical uplink shared channel using a subframe index of the subframe in which the grant is received and the parameter indicating a window length received in the grant.

3. The method according to claim 1, further comprising:

determining the set of subframes for possible transmission of the physical uplink shared channel using a subframe index of the subframe in which the grant is received and a parameter indicating a window length that is configured via higher layers that are higher than the physical layer.

4. The method according to claim 1,

wherein the grant for transmitting physical uplink shared channel includes a hybrid automatic repeat request identifier,

wherein the method further comprises:

including the hybrid automatic repeat request identifier along with each physical uplink shared channel transmission in the multiple subframes; and

including a hybrid automatic repeat request sub identifier along with each physical uplink shared channel transmission of the physical uplink shared channel transmissions in the multiple subframes, where the hybrid automatic repeat request sub identifier is set to 0 for a first physical uplink shared channel transmission of the physical uplink shared channel transmissions in the multiple subframes, is set to 1 for a second physical uplink shared channel transmission of the physical uplink shared channel transmission in the multiple subframes, and is incremented for each subsequent physical uplink shared channel transmission of the physical uplink shared channel transmissions in the multiple subframes.

5. The method according to claim 4,

wherein the hybrid automatic repeat request identifier is a 3 bit identifier, and

wherein the hybrid automatic repeat request sub identifier is a 2 bit identifier.

6. The method according to claim 5,

wherein the grant comprises a first grant, and

wherein the method further comprises:

receiving a second grant for a retransmission, where the second grant includes the same hybrid automatic repeat request identifier received in the first grant and at least one hybrid automatic repeat request sub identifier that was previously transmitted by the user equipment; and

transmitting a physical uplink shared channel transmission in response to the second grant to retransmit data that is associated with the same hybrid automatic repeat request identifier and the at least one hybrid automatic repeat request sub identifier.

7. The method according to claim 5, further comprising:

determining a demodulation reference signal cyclic shift value based on the hybrid automatic repeat request identifier; and

transmitting a demodulation reference signal using the determined cyclic shift value, along with each physical uplink shared channel transmission of the physical uplink shared channel transmissions in the multiple subframes.

8. The method according to claim 5, further comprising:

determining a demodulation reference signal cyclic shift value based on the hybrid automatic repeat request identifier and at least one hybrid automatic repeat request sub identifier; and

transmitting a demodulation reference signal using the determined cyclic shift value, along with at least one physical uplink shared channel transmission of the physical uplink shared channel transmissions in the multiple subframes.

9. The method according to claim 5, further comprising multiplexing bits indicating the hybrid automatic repeat request identifier into a portion of resources assigned for each physical uplink shared channel transmission of the physical uplink shared channel transmissions in the multiple subframes.

10. The method according to claim 5, further comprising multiplexing bits indicating the hybrid automatic repeat request identifier and the hybrid automatic repeat request sub identifier into a portion of resources assigned for each physical uplink shared channel transmission of the physical uplink shared channel transmissions in the multiple subframes.

11. The method according to claim 1,

wherein the grant for transmitting physical uplink shared channel includes a hybrid automatic repeat request identifier,

wherein the method further comprises:

determining a new hybrid automatic repeat request identifier for each physical uplink shared channel transmission of the physical uplink shared channel transmissions in the multiple subframes made in response to the grant, where the new hybrid automatic repeat request identifier is determined based on the received hybrid automatic repeat request identifier and an order of the physical uplink shared channel transmission within the physical uplink shared channel transmission in the multiple subframes; and

transmitting each new hybrid automatic repeat request identifier along with each physical uplink shared channel transmission.

12. The method according to claim 11, wherein different new hybrid automatic repeat request identifier values are used for each physical uplink shared channel transmission.

13. The method according to claim 11,

wherein the grant comprises a first grant, and

wherein the method further comprises:

receiving a second grant requesting a retransmission, where the second grant includes a hybrid automatic repeat request identifier that was previously transmitted by the user equipment; and

transmitting physical uplink shared channel in response to the second grant to retransmit data that is associated with the same hybrid automatic repeat request identifier that was previously transmitted by the user equipment.

14. The method according to claim 11, further comprising:

determining a demodulation reference signal cyclic shift value based on the hybrid automatic repeat request identifier; and

transmitting a demodulation reference signal using the determined cyclic shift value, along with each physical uplink shared channel transmission of the physical uplink shared channel transmissions in the multiple subframes.

15. The method according to claim 11, further comprising:

determining a demodulation reference signal cyclic shift value for each physical uplink shared channel transmission of the physical uplink shared channel transmissions in the multiple subframes, based the new hybrid automatic repeat request identifier for each physical uplink shared channel transmission; and

transmitting a demodulation reference signal along with each physical uplink shared channel transmission of the physical uplink shared channel transmissions in the multiple subframes, using the determined cyclic shift value for each physical uplink shared channel transmission.

16. The method according to claim 11, further comprising multiplexing bits indicating the new hybrid automatic repeat request identifier into a portion of resources assigned for each physical uplink shared channel transmission of the physical uplink shared channel transmissions in the multiple subframes.

17. The method according to claim 1,

wherein the grant comprises a first grant for transmitting physical uplink shared channel including a hybrid automatic repeat request identifier,

wherein the method further comprises:

determining a new hybrid automatic repeat request identifier for each physical uplink shared channel transmission of the physical uplink shared channel transmissions in the multiple subframes made in response to the grant, where the new hybrid automatic repeat request identifier is determined based on the received hybrid automatic repeat request identifier and a subframe index of each subframe of the multiple subframes;

receiving, after receiving the first grant, a second grant requesting a retransmission, where the second grant includes at least one new hybrid automatic repeat request identifier that was previously determined by the user equipment; and

transmitting physical uplink shared channel in response to the second grant to retransmit the data that is associated with the same new hybrid automatic repeat request identifier.

18. The method according to claim 17, wherein different new hybrid automatic repeat request identifier values are used for each physical uplink shared channel transmission of the physical uplink shared channel transmissions in the multiple subframes.

19. The method according to claim 17, further comprising:

receiving multiple new data indicators within the grant, where each new data indicator value is associated with each subframe within the determined set of subframes for possible transmission of physical uplink shared channel; and

transmitting either new data or retransmission in each subframe according to the new data indicator value.

20. An apparatus comprising:

a transceiver configured to receive, in a subframe, a grant for transmitting physical uplink shared channel on a serving cell operating on an unlicensed spectrum; and

a controller configured to determine a set of subframes for possible transmission of the physical uplink shared channel, and configured to perform listen before talk on the unlicensed carrier to determine an earliest unoccupied subframe in the set of subframes,

wherein the transceiver is configured to transmit physical uplink shared channel transmissions in multiple subframes within the set of subframes on the unlicensed carrier, starting with the earliest unoccupied subframe, in response to receiving the grant.

21. The apparatus according to claim 20,

wherein the grant for transmitting physical uplink shared channel includes a hybrid automatic repeat request identifier,

wherein the transceiver is configured to include the hybrid automatic repeat request identifier along with each physical uplink shared channel transmission in the multiple subframes, and configured to include a hybrid automatic repeat request sub identifier along with each physical uplink shared channel transmission of the physical uplink shared channel transmissions in the multiple subframes, where the hybrid automatic repeat request sub identifier is set to 0 for the first physical uplink shared channel transmission of the physical uplink shared channel transmissions in the multiple subframes, is set to 1 for the second physical uplink shared channel transmission of the physical uplink shared channel transmission in the multiple subframes, and is incremented for each subsequent physical uplink shared channel transmission of the physical uplink shared channel transmission in the multiple subframes.

22. The apparatus according to claim 20,

wherein the grant for transmitting physical uplink shared channel includes a hybrid automatic repeat request identifier,

wherein the controller is configured to determine a new hybrid automatic repeat request identifier for each physical uplink shared channel transmission of the physical uplink shared channel transmissions in the multiple subframes made in response to the grant, where the new hybrid automatic repeat request identifier is determined based on the received hybrid automatic repeat request identifier and an order of the physical uplink shared channel transmission within the physical uplink shared channel transmission in the multiple subframes, and

wherein the transceiver is configured to transmit each new hybrid automatic repeat request identifier along with each physical uplink shared channel transmission.

23. The apparatus according to claim 20,

wherein the grant comprises a first grant for transmitting physical uplink shared channel including a hybrid automatic repeat request identifier,

wherein the controller is configured to determine a new hybrid automatic repeat request identifier for each physical uplink shared channel transmission of the physical uplink shared channel transmissions in the multiple subframes made in response to the grant, where the new hybrid automatic repeat request identifier is determined based on the received hybrid automatic repeat request identifier and a subframe index of each subframe of the multiple subframes, and

wherein the transceiver is configured to receive, after receiving the first grant, a second grant requesting a retransmission, where the second grant includes at least one new hybrid automatic repeat request identifier that was previously determined, and configured to transmit physical uplink shared channel in response to the second grant to retransmit the data that is associated with the same new hybrid automatic repeat request identifier.