Techniques of transmitting overlapping uplink channels

1. A method of wireless communication of a user equipment (UE), comprising:

receiving downlink control information (DCI) in a downlink control channel (DCCH), the DCI indicating a first uplink (UL) channel;

determining a second UL channel that has been scheduled prior to receiving the DCI;

determining that the first UL channel overlaps with the second UL channel in a time domain;

determining whether an earliest symbol period from the first UL channel and the second UL channel is within a predetermined time period from a last symbol period of the DCCH; and

determining that an unexpected event has occurred or transmitting one of the first UL channel and the second UL channel, when the earliest symbol period is within the predetermined time period.

2. The method of claim 1 , wherein the scheduling of the second UL channel is semi-static or semi-persistent.

3. The method of claim 1 , wherein each of the first UL channel and the second UL channel is a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH).

4. The method of claim 3 , wherein the first UL channel is a PUCCH, wherein the second UL channel is another PUCCH.

5. The method of claim 4 , further comprising:

combining the first UL channel and the second UL channel to obtain a combined UL channel, when the earliest symbol period is not within the predetermined time period.

6. The method of claim 5 , further comprising:

transmitting, in the combined UL channel, both uplink control information (UCI) to be carried in the first UL channel and UCI to be carried in the second UL channel.

7. The method of claim 4 , further comprising:

transmitting one of the first UL channel and the second UL channel, when the earliest symbol period is not within the predetermined time period.

8. The method of claim 1 , wherein the first UL channel is for carrying a hybrid automatic repeat request (HARD) acknowledgment.

9. The method of claim 1 , wherein the second UL channel is for carrying a channel state information (CSI) report or a scheduling request (SR).

10. The method of claim 1 , wherein at least one symbol period (a) is in one of the first UL channel and the second UL channel and (b) is not in the other one of the first UL channel and the second UL channel.

11. The method of claim 1 , further comprising determining the predetermined time period based on a processing time defined for the UE to decode a DCCH and to prepare a Physical Uplink Shared Channel (PUSCH).

12. The method of claim 11 , wherein the predetermined time period is the processing time and a fixed number of additional symbol periods.

13. The method of claim 1 , further comprising: transmitting one of the first UL channel and the second UL channel that contains the earliest symbol period, when (a) the earliest symbol period is within the predetermined time period and (b) an initial symbol period of the first UL channel and an initial symbol period of the second UL channel are not the same symbol period.

14. The method of claim 1 , further comprising: transmitting one of the first UL channel and the second UL channel that has a higher priority level than the other in accordance with a predetermined rule, when (a) the earliest symbol period is within the predetermined time period and (b) an initial symbol period of the first UL channel and an initial symbol period of the second UL channel are the same symbol period.

15. The method of claim 14 , wherein the predetermined rule defines (a) that a UL channel carrying a hybrid automatic repeat request (HARQ) acknowledgment has a priority level higher than that of a UL channel carrying a scheduling request (SR) and (b) that a UL channel carrying a SR has a priority level higher than that of a UL channel carrying channel state information (CSI).

16. The method of claim 1 , wherein one of the first UL channel and the second UL channel that has a higher priority than the other in accordance with a predetermined rule is transmitted, when the earliest symbol period is within the predetermined time period.

17. The method of claim 16 , wherein the predetermined rule defines (a) that a UL channel carrying a hybrid automatic repeat request (HARQ) acknowledgment has a priority level higher than that of a UL channel carrying a scheduling request (SR) and (b) that a UL channel carrying a SR has a priority level higher than that of a UL channel carrying channel state information (CSI).

18. An apparatus for wireless communication, the apparatus being a user equipment (UE), comprising:

a memory; and

at least one processor coupled to the memory and configured to:

receive downlink control information (DCI) in a downlink control channel (DCCH), the DCI indicating a first uplink (UL) channel;

determine a second UL channel that has been scheduled prior to receiving the DCI;

determine that the first UL channel overlaps with the second UL channel in a time domain;

determine whether an earliest symbol period from the first UL channel and the second UL channel is within a predetermined time period from a last symbol period of the DCCH; and

determine that an unexpected event has occurred or transmitting one of the first UL channel and the second UL channel, when the earliest symbol period is within the predetermined time period.

19. An apparatus of claim 18 , wherein the at least one processor is further configured to:

combine the first UL channel and the second UL channel to obtain a combined UL channel, when the earliest symbol period is not within the predetermined time period.

20. A non-transitory computer-readable medium storing computer executable code for wireless communication of wireless equipment, comprising code to:

receive downlink control information (DCI) in a downlink control channel (DCCH), the DCI indicating a first uplink (UL) channel;

determine a second UL channel that has been scheduled prior to receiving the DCI;

determine that the first UL channel overlaps with the second UL channel in a time domain;

determine whether an earliest symbol period from the first UL channel and the second UL channel is within a predetermined time period from a last symbol period of the DCCH; and

determine that an unexpected event has occurred or transmitting one of the first UL channel and the second UL channel, when the earliest symbol period is within the predetermined time period.