Method and apparatus for wireless communication in wireless communication system

1. A method of transmitting uplink data, the method comprising:

establishing connections with a first serving cell and a second serving cell;

determining, by a user equipment (UE), a time period for a device-to-device (D2D) discovery signal communication via the second serving cell;

receiving, by the UE and via the first serving cell, an uplink grant in subframe n;

determining, by the UE and based on the uplink grant received via the first serving cell, a first subframe associated with an uplink signal to an evolved NodeB (eNB) associated with the first serving cell;

in response to determining that the first subframe overlaps in time with the time period, refraining from transmitting the uplink signal in the first subframe, and transmitting, based on a retransmission timing, the uplink signal; and

transmitting, based on a reception timing of the uplink grant and based on a non-adaptive retransmission, the uplink signal in subframe n+12,

wherein the first subframe corresponds to subframe n+4.

2. The method of claim 1 , further comprising:

in response to determining that the first subframe overlaps in time with the time period, refraining from transmitting Hybrid Automatic Repeat Request (HARD) feedback in the first subframe.

3. The method of claim 1 , wherein the time period comprises a plurality of subframes associated with the second serving cell.

4. A method of transmitting uplink data, the method comprising:

determining, by a user equipment (UE), a time period for monitoring a device-to-device (D2D) discovery signal communication;

determining, by the UE, a first subframe associated with a Hybrid Automatic Repeat Request (HARQ) feedback reception; and

based on whether the first subframe overlaps in time with the time period, setting a state variable associated with the HARQ feedback reception to acknowledgement.

5. The method of claim 4 , wherein setting the state variable associated with the HARQ feedback reception to acknowledgement comprises:

in response to determining that the first subframe overlaps in time with the time period and determining that a Media Access Control Protocol Data Unit (MAC PDU) was not obtained from a Message3 buffer, setting, by a MAC entity of the UE, the state variable associated with the HARQ feedback reception to acknowledgement.

6. The method of claim 5 , wherein the MAC entity of the UE sets the state variable associated with the HARQ feedback reception to acknowledgement without confirming acknowledgement information of the HARQ feedback reception scheduled to be received in the first subframe.

7. A user equipment (UE) to transmit uplink data, the UE comprising:

a transmitter;

one or more processors; and

memory storing instructions, when executed by the one or more processors, that cause the UE to:

establish connections with a first serving cell and a second serving cell;

determine a time period for a device-to-device (D2D) discovery signal communication via the second serving cell;

receive, via the first serving cell, an uplink grant in subframe n;

determine, based on the uplink grant received via the first serving cell, a first subframe associated with an uplink signal to an evolved NodeB (eNB) associated with the first serving cell;

in response to determining that the first subframe overlaps in time with the time period, control the transmitter to refrain from transmitting the uplink signal in the first subframe, and control the transmitter to transmit, based on a retransmission timing, the uplink signal; and

control the transmitter to transmit, based on a reception timing of the uplink grant and based on a non-adaptive retransmission, the uplink signal in subframe n+12,

wherein the first subframe corresponds to subframe n+4.

8. The UE of claim 7 , wherein the instructions, when executed by the one or more processors, cause the UE to control, in response to determining that the first subframe overlaps in time with the time period, the transmitter to refrain from transmitting Hybrid Automatic Repeat Request (HARD) feedback in the first subframe.

9. The UE of claim 7 , wherein the time period comprises a plurality of subframes associated with the second serving cell.

10. A user equipment (UE) comprising:

one or more processors; and

memory storing instructions, when executed by the one or more processors, that cause the UE to:

determine a time period for monitoring a device-to-device (D2D) discovery signal communication;

determine a first subframe associated with a Hybrid Automatic Repeat Request (HARQ) feedback reception; and

set, based on whether the first subframe overlaps in time with the time period, a state variable associated with the HARQ feedback reception to acknowledgement.

11. The UE of claim 10 , wherein setting the state variable associated with the HARQ feedback reception to acknowledgement comprises:

in response to determining that the first subframe overlaps in time with the time period and determining that a Media Access Control Protocol Data Unit (MAC PDU) was not obtained from a Message3 buffer, setting, by a MAC entity of the UE, the state variable associated with the HARQ feedback reception to acknowledgement.

12. The UE of claim 11 , wherein the MAC entity of the UE sets the state variable associated with the HARQ feedback reception to acknowledgement without confirming acknowledgement information of the HARQ feedback reception scheduled to be received in the first subframe.