Method and apparatus for partial retransmission in wireless cellular communication system

A method performed by a base station in a communication system, the method comprising:

• determining a number of code block groups (CBGs) of a transport block (TB);
• transmitting, to a terminal, information on the determined number of the CBGs of the TB via higher layer signaling, wherein a CBG includes one or more code blocks (CBs) of the TB;
• transmitting, to the terminal, downlink control information (DCI) scheduling downlink data transmission, wherein the DCI includes a new data indicator (NDI) and a CBG indicator;
• and
• transmitting, to the terminal, data corresponding to the TB,
• wherein in response to the NDI indicating that the data corresponds to an initial transmission of the TB, the data includes the CBGs of the TB, and
• wherein in response to the NDI indicating that the data corresponds to a retransmission of the TB, the data includes one or more CBGs of the CBGs, wherein each bit of the CBG indicator indicates whether a corresponding CBG of the TB is present or not in the data.

A terminal in a communication system, the terminal comprising:

• a transceiver;
• and
• a controller configured to:
• receive, from a base station via the transceiver, information on a number of code block groups (CBGs) of a transport block (TB) via higher layer signaling, wherein a CBG includes one or more code blocks (CBs) of the TB,
• identify the number of the CBGs of the TB based on the information on the number of the CBGs,
• receive, from the base station, via the transceiver, downlink control information (DCI) scheduling downlink data transmission, wherein the DCI includes a new data indicator (NDI) and a CBG indicator,
• receive, from the base station, via the transceiver, data corresponding to the TB based on the DCI,
• determine, based on the NDI, whether the data corresponds to an initial transmission of the TB or a retransmission of the TB,
• in response to determining that the data corresponds to the initial transmission of the TB, decode the received data including the CBGs, and
• in response to determining that the data corresponds to the retransmission of the TB, decode the received data including one or more CBGs of the CBGs based on the CBG indicator, wherein each bit of the CBG indicator indicates whether a corresponding CBG of the TB is present or not in the received data.

A base station in a communication system, the base station comprising:

• a transceiver;
• and
• a controller configured to:
• determine a number of code block groups (CBGs) of a transport block (TB),
• transmit, to a terminal, via the transceiver, information on the determined number of the CBGs of the TB via higher layer signaling, wherein a CBG includes one or more code blocks (CBs) of the TB,
• transmit, to the terminal, via the transceiver, downlink control information (DCI) scheduling downlink data transmission, wherein the DCI includes a new data indicator (NDI) and a CBG indicator, and
• transmit, to the terminal, via the transceiver, data corresponding to the TB,
• wherein in response to the NDI indicating that the data corresponds to an initial transmission of the TB, the data includes the CBGs of the TB, and
• wherein in response to the NDI indicating that the data corresponds to a retransmission of the TB, the data includes one or more CBGs of the CBGs, wherein each bit of the CBG indicator indicates whether a corresponding CBG of the TB is present or not in the data.