Method and apparatus for determining transport block size in wireless communication system

1. A method for transmitting data and acknowledgement/negative-acknowledgement (ACK/NACK) in a wireless communication system, the method performed by a user equipment (UE) and comprising:

determining a number of effective resource blocks;

determining a transport block size (TBS) of data transmitted on an uplink data channel according to the number of effective resource blocks;

multiplexing the data and the ACK/NACK in a transport block having the determined TBS; and

transmitting the data and the ACK/NACK through the uplink data channel,

wherein the number of effective resource blocks is determined based on remaining resources by excluding resources for transmitting control information from resources allocated to the uplink data channel,

wherein the resources for transmitting control information are calculated using a predetermined modulation and coding scheme (MCS) regardless of an actual MCS applied to the control information, and

wherein a number of symbols (M HARQ-ACK ) used to transmit the ACK/NACK is determined by the following equation,

M

HARQ

-

ACK

=

⌈

N

HARQ

-

ACK

·

10

Δ

HARQ

-

ACK

10

·

MCS

ref

⌉

,

where N HARQ-ACK denotes a payload size of the ACK/NACK, Δ HARQ-ACK denotes a variable which indicates an offset value in unit of decibel (dB) to compensate for a difference between a block error rate (BLER) of the data and a BLER of the ACK/NACK and a difference between a method of encoding the data and a method of encoding the ACK/NACK, and MCS ref denotes an MCS used in encoding of the data.

2. The method of claim 1 , wherein the number of effective resource blocks is determined based on a value obtained by dividing the remaining resources by a unit of resource blocks.

3. The method of claim 1 , wherein the uplink data channel is a physical uplink shared channel (PUSCH).

4. The method of claim 1 , wherein the transport block size is determined based on an index I TBS , which is determined by using an index I MCS indicating the MCS, and the number of effective resource blocks.

5. An apparatus comprising:

a radio frequency (RF) unit configured to transmit and receive a radio signal; and

a processor operatively coupled to the RF unit,

wherein the processor is configured to:

determine a number of effective resource blocks,

determine a transport block size (TBS) of data transmitted on an uplink data channel according to the number of effective resource blocks,

multiplex the data and acknowledgement/negative-acknowledgement (ACK/NACK) in a transport block having the determined TBS, and

transmit the data and the ACK/NACK through the uplink data channel,

wherein the number of effective resource blocks is determined based on remaining resources by excluding resources for transmitting control information from resources allocated to the uplink data channel,

wherein the resources for transmitting control information are calculated using a predetermined modulation and coding scheme (MCS) regardless of an actual MCS applied to the control information, and

wherein a number of symbols (M HARQ-ACK ) used to transmit the ACK/NACK is determined by the following equation,

M

HARQ

-

ACK

=

⌈

N

HARQ

-

ACK

·

10

Δ

HARQ

-

ACK

10

·

MCS

ref

⌉

,

where N HARQ-ACK denotes a payload size of the ACK/NACK, Δ HARQ-ACK denotes a variable which indicates an offset value in unit of decibel (dB) to compensate for a difference between a block error rate (BLER) of the data and a BLER of the ACK/NACK and a difference between a method of encoding the data and a method of encoding the ACK/NACK, and MCS ref denotes an MCS used in encoding of the data.

6. The apparatus of claim 5 , wherein the number of effective resource blocks is determined based on a value obtained by dividing the remaining resources by a unit of resource blocks.

7. The apparatus of claim 5 , wherein the uplink data channel is a physical uplink shared channel (PUSCH).

8. The apparatus of claim 5 , wherein the transport block size is determined based on an index I TBS , which is determined by using an index I MCS indicating the MCS, and the number of effective resource blocks.