Uplink scheduling for license assisted access

1. A method of wireless communication, comprising:

receiving a conditional grant including a transmission configuration for uplink transmissions;

receiving an uplink activation grant over a contention-based shared carrier, wherein the uplink activation grant activates the uplink transmission associated with the conditional grant; and

transmitting the uplink transmissions on the contention-based shared carrier according to the transmission configuration, wherein the transmitting is in response to the uplink activation grant;

wherein the receiving the uplink activation grant includes detecting a common reference signal of a serving base station in a first symbol over the contention-based shared carrier.

2. The method of claim 1 , wherein the conditional grant is received via one of:

a non-contention-based carrier; or

the contention-based shared carrier.

3. The method of claim 2 , wherein the conditional grant is received in one of:

a single transmission per subframe;

multiple transmission time intervals (TTIs); or

a semi-persistent scheduling (SPS) grant.

4. The method of claim 1 , wherein the conditional grant is received via one of: a physical downlink control channel (PDCCH) or an enhanced PDCCH (EPDCCH), regardless of any other control channel on the contention-based shared carrier on which downlink grants are carried.

5. The method of claim 1 , wherein the receiving the uplink activation grant includes:

identifying a transmission indication in the uplink activation grant, wherein the transmission indication identifies which UEs of a plurality of served UEs are scheduled for transmission, wherein the transmitting is triggered in response to identifying the transmission indication.

6. The method of claim 5 , wherein the uplink activation grant provides a schedule of the uplink transmission for the identified UEs indicated for transmission during the uplink transmission opportunity via one of: explicit signaling or implicit signaling.

7. The method of claim 1 , wherein the transmission configuration includes one or more of:

a transport block size;

a modulation and coding scheme (MCS);

a resource assignment;

a number of interleaves;

hybrid automatic repeat request (HARQ) identifier (ID);

redundancy level.

8. The method of claim 1 , wherein the conditional grant includes a process identifier (ID) associated with a subframe and the transmission configuration includes one or more of: a modulation and coding scheme (MCS), a number of interleaves, transport block size, and resource assignment,

wherein the transmitting includes transmitting the process ID with the uplink transmission.

9. The method of claim 8 , further including:

detecting an uplink retransmission scheduled for retransmission;

determining the transport block size associated with the previous transmission for which the uplink retransmission is scheduled is equal to a current transport block size associated with a current transmission; and

prioritizing retransmission of the scheduled uplink retransmission over the current transmission, wherein the transmitting the uplink transmission includes transmitting the process ID associated with the previous transmission.

10. An apparatus configured for wireless communication, comprising:

means for receiving a conditional grant including a transmission configuration for uplink transmissions;

means for receiving an uplink activation grant over a contention-based shared carrier, wherein the uplink activation grant activates the uplink transmission associated with the conditional grant; and

means for transmitting the uplink transmissions on the contention-based shared carrier according to the transmission configuration, wherein the means for transmitting is executed in response to the uplink activation grant;

wherein the means for receiving the uplink activation grant includes means for detecting a common reference signal of a serving base station in a first symbol over the contention-based shared carrier.

11. The apparatus of claim 10 , wherein the conditional grant is received via one of:

a non-contention-based carrier; or

the contention-based shared carrier.

12. The apparatus of claim 11 , wherein the conditional grant is received in one of:

a single transmission per subframe;

multiple transmission time intervals (TTIs); or

a semi-persistent scheduling (SPS) grant.

13. The apparatus of claim 10 , wherein the conditional grant is received via one of: a physical downlink control channel (PDCCH) or an enhanced PDCCH (EPDCCH), regardless of any other control channel on the contention-based shared carrier on which downlink grants are carried.

14. The apparatus of claim 10 , wherein the means for receiving the uplink activation grant includes:

means for identifying a transmission indication in the uplink activation grant, wherein the transmission indication identifies which UEs of a plurality of served UEs are scheduled for transmission, wherein the means for transmitting is triggered in response to the means for identifying the transmission indication.

15. The apparatus of claim 14 , wherein the uplink activation grant provides a schedule of the uplink transmission for the identified UEs indicated for transmission during the uplink transmission opportunity via one of: explicit signaling or implicit signaling.

16. The apparatus of claim 10 , wherein the transmission configuration includes one or more of:

a transport block size;

a modulation and coding scheme (MCS);

a resource assignment;

a number of interleaves;

hybrid automatic repeat request (HARQ) identifier (ID);

redundancy level.

17. The apparatus of claim 10 , wherein the conditional grant includes a process identifier (ID) associated with a subframe and the transmission configuration includes one or more of: a modulation and coding scheme (MCS), a number of interleaves, transport block size, and resource assignment,

wherein the means for transmitting includes means for transmitting the process ID with the uplink transmission.

18. The apparatus of claim 17 , further including:

means for detecting an uplink retransmission scheduled for retransmission;

means for determining the transport block size associated with the previous transmission for which the uplink retransmission is scheduled is equal to a current transport block size associated with a current transmission; and

means for prioritizing retransmission of the scheduled uplink retransmission over the current transmission, wherein the means for transmitting the uplink transmission includes means for transmitting the process ID associated with the previous transmission.

19. A non-transitory computer-readable medium having a computer program product recorded thereon, the computer program product comprising:

program code for causing a computer to receive a conditional grant including a transmission configuration for uplink transmissions;

program code for causing the computer to receive an uplink activation grant over a contention-based shared carrier, wherein the uplink activation grant indicates an uplink transmission opportunity; and

program code for causing the computer to transmit the uplink transmissions on the contention-based shared carrier according to the transmission configuration, wherein the program code for causing the computer to transmit is executed in response to the uplink activation grant;

wherein the program code for causing the computer to receive the uplink activation grant includes program code for causing the computer to detect a common reference signal of a serving base station in a first symbol over the contention-based shared carrier.

20. The non-transitory computer-readable medium of claim 19 , wherein the conditional grant is received via one of:

a non-contention-based carrier; or

the contention-based shared carrier.

21. The non-transitory computer-readable medium of claim 20 , wherein the conditional grant is received in one of:

a single transmission per subframe;

multiple transmission time intervals (TTIs); or

a semi-persistent scheduling (SPS) grant.

22. The non-transitory computer-readable medium of claim 19 , wherein the conditional grant is received via one of: a physical downlink control channel (PDCCH) or an enhanced PDCCH (EPDCCH), regardless of any other control channel on the contention-based shared carrier on which downlink grants are carried.

23. The non-transitory computer-readable medium of claim 19 , wherein the program code for causing the computer to receive the uplink activation grant includes:

program code for causing the computer to identify a transmission indication in the uplink activation grant, wherein the transmission indication identifies which UEs of a plurality of served UEs are scheduled for transmission, wherein the program code for causing the computer to transmit is triggered in response to identifying the transmission indication.

24. The non-transitory computer-readable medium of claim 23 , wherein the uplink activation grant provides a schedule of the uplink transmission for the identified UEs indicated for transmission during the uplink transmission opportunity via one of: explicit signaling or implicit signaling.

25. The non-transitory computer-readable medium of claim 19 , wherein the transmission configuration includes one or more of:

a transport block size;

a modulation and coding scheme (MCS);

a resource assignment;

a number of interleaves;

hybrid automatic repeat request (HARD) identifier (ID);

redundancy level.

26. The non-transitory computer-readable medium of claim 19 , wherein the conditional grant includes a process identifier (ID) associated with a subframe and the transmission configuration includes one or more of: a modulation and coding scheme (MCS), a number of interleaves, transport block size, and resource assignment,

wherein the program code for causing the computer to transmit includes program code for causing the computer to transmit the process ID with the uplink transmission.

27. The non-transitory computer-readable medium of claim 26 , further including:

program code for causing the computer to detect an uplink retransmission scheduled for retransmission;

program code for causing the computer to determine the transport block size associated with the previous transmission for which the uplink retransmission is scheduled is equal to a current transport block size associated with a current transmission; and

program code for causing the computer to prioritize retransmission of the scheduled uplink retransmission over the current transmission, wherein the program code for causing the computer to transmit the uplink transmission includes program code for causing the computer to transmit the process ID associated with the previous transmission.

28. An apparatus configured for wireless communication, the apparatus comprising:

at least one processor; and

a memory coupled to the at least one processor,

wherein the at least one processor is configured:

to receive a conditional grant including a transmission configuration for uplink transmissions;

to receive an uplink activation grant over a contention-based shared carrier, wherein the uplink activation grant indicates an uplink transmission opportunity; and

to transmit the uplink transmissions on the contention-based shared carrier according to the transmission configuration, wherein the configuration to transmit is performed in response to the uplink activation grant;

wherein the configuration of the at least one processor to receive the uplink activation grant includes configuration of the at least one processor to detect a common reference signal of a serving base station in a first symbol over the contention-based shared carrier.

29. The apparatus of claim 28 , wherein the conditional grant is received via one of:

a non-contention-based carrier; or

the contention-based shared carrier.

30. The apparatus of claim 29 , wherein the conditional grant is received in one of:

a single transmission per subframe;

multiple transmission time intervals (TTIs); or

a semi-persistent scheduling (SPS) grant.

31. The apparatus of claim 28 , wherein the conditional grant is received via one of: a physical downlink control channel (PDCCH) or an enhanced PDCCH (EPDCCH), regardless of any other control channel on the contention-based shared carrier on which downlink grants are carried.

32. The apparatus of claim 28 , wherein the configuration of the at least one processor to receive the uplink activation grant includes:

configuration of the at least one processor to identify a transmission indication in the uplink activation grant, wherein the transmission indication identifies which UEs of a plurality of served UEs are scheduled for transmission, wherein the configuration to transmit is triggered in response to identifying the transmission indication.

33. The apparatus of claim 32 , wherein the uplink activation grant provides a schedule of the uplink transmission for the identified UEs indicated for transmission during the uplink transmission opportunity via one of: explicit signaling or implicit signaling.

34. The apparatus of claim 28 , wherein the transmission configuration includes one or more of:

a transport block size;

a modulation and coding scheme (MCS);

a resource assignment;

a number of interleaves;

hybrid automatic repeat request (HARQ) identifier (ID);

redundancy level.

35. The apparatus of claim 28 , wherein the conditional grant includes a process identifier (ID) associated with a subframe and the transmission configuration includes one or more of: a modulation and coding scheme (MCS), a number of interleaves, transport block size, and resource assignment,

wherein the configuration of the at least one processor to transmit includes configuration to transmit the process ID with the uplink transmission.

36. The apparatus of claim 35 , further including configuration of the at least one processor:

to detect an uplink retransmission scheduled for retransmission;

to determine the transport block size associated with the previous transmission for which the uplink retransmission is scheduled is equal to a current transport block size associated with a current transmission; and

to prioritize retransmission of the scheduled uplink retransmission over the current transmission, wherein the configuration of the at least one processor to transmit the uplink transmission includes configuration to transmit the process ID associated with the previous transmission.