A method for performing channel coding on downlink control information, DCI, based on a polar code by a transmission device, the method comprising: performing the channel coding on a first DCI input information, a second DCI input information and a third DCI input information based on a generator matrix for a polar code; characterized by: determining an aggregation level of a first DCI output information based on a channel condition of a terminal having a poorer channel condition among a first terminal and a second terminal, wherein the first DCI output information is generated as a result of the channel coding; determining an aggregation level of a second DCI output information based on a channel condition of the first terminal, wherein the second DCI output information is generated as a result of the channel coding; determining an aggregation level of a third DCI output information based on a channel condition of the second terminal, wherein the third DCI output information is generated as a result of the channel coding; transmitting, to the first terminal, the first DCI output information and the second DCI output information; and transmitting, to the second terminal, the first DCI output information and the third DCI output information, wherein the first DCI output information is generated based on only the first DCI input information, wherein the second DCI output information is generated based on both the first DCI output information and the second DCI input information, wherein the third DCI output information is generated based on the first DCI output information and the third DCI input information. performing the channel coding on a first DCI input information, a second DCI input information and a third DCI input information based on a generator matrix for a polar code; characterized by: determining an aggregation level of a first DCI output information based on a channel condition of a terminal having a poorer channel condition among a first terminal and a second terminal, wherein the first DCI output information is generated as a result of the channel coding; determining an aggregation level of a second DCI output information based on a channel condition of the first terminal, wherein the second DCI output information is generated as a result of the channel coding; determining an aggregation level of a third DCI output information based on a channel condition of the second terminal, wherein the third DCI output information is generated as a result of the channel coding; transmitting, to the first terminal, the first DCI output information and the second DCI output information; and transmitting, to the second terminal, the first DCI output information and the third DCI output information, wherein the first DCI output information is generated based on only the first DCI input information, wherein the second DCI output information is generated based on both the first DCI output information and the second DCI input information, wherein the third DCI output information is generated based on the first DCI output information and the third DCI input information. determining an aggregation level of a first DCI output information based on a channel condition of a terminal having a poorer channel condition among a first terminal and a second terminal, wherein the first DCI output information is generated as a result of the channel coding; determining an aggregation level of a second DCI output information based on a channel condition of the first terminal, wherein the second DCI output information is generated as a result of the channel coding; determining an aggregation level of a third DCI output information based on a channel condition of the second terminal, wherein the third DCI output information is generated as a result of the channel coding; transmitting, to the first terminal, the first DCI output information and the second DCI output information; and transmitting, to the second terminal, the first DCI output information and the third DCI output information, wherein the first DCI output information is generated based on only the first DCI input information, wherein the second DCI output information is generated based on both the first DCI output information and the second DCI input information, wherein the third DCI output information is generated based on the first DCI output information and the third DCI input information.