![uplink downlink uplink downlink](https://d3i71xaburhd42.cloudfront.net/f0470ba9bd927252d37c3abf7a4570adef27427b/5-Figure3-1.png)
The method of claim 8, wherein the downlink RBG comprises assignment information regarding the downlink RBSG and a UE-identification (ID) indicating a UE for each downlink RBSG. The method of claim 1, wherein the downlink RBG comprises a downlink resource block sub-group (RBSG), and the number of downlink RBs in the downlink RBSG varies depending on the number of downlink RBs in the downlink RBG. The method of claim 1, wherein the number of downlink RBs in the downlink RBG is designated by a radio resource control (RRC) or by a common control channel. The method of claim 1, wherein the downlink RBG comprises at least 4 downlink RBs. The method of claim 1, wherein the number of uplink RBs in the uplink RBG varies depending on the number of downlink RBs in the downlink RBG. The method of claim 1, wherein a start RB index of the uplink RBG is mapped to a start RB index of the downlink RBG, and wherein the control information for the mapping indicates an uplink RBG mapped to the downlink RBG through information regarding the start RB index of the downlink RBG. The method of claim 2, wherein if the downlink frequency band is greater than or equal to the uplink frequency band, the mapping comprises setting the number of uplink RBs in the downlink RBG and the uplink RBG mapped next to be less than or equal to the number of downlink RBs in the downlink RBG, and mapping a start RB index of the uplink RBG to a start RB index of the downlink RBG. The method of claim 1, further comprising, if the downlink frequency band is greater than or equal to the uplink frequency band, mapping the downlink RBG to the uplink RBG, wherein if the downlink frequency band is greater than or equal to the uplink frequency band, the mapping comprises mapping the downlink RBG to the uplink RBG sequentially in a descending order of the number of downlink RBs in the downlink RBG, setting the number of uplink RBs in the uplink RBG first mapped to the downlink RBG to be equal to the number of downlink RBs in the downlink RBG, and mapping a start RB index of the uplink RBG to a start RB index of the downlink RBG. Transmitting control information for the mapping through the downlink RBG. If the downlink frequency band is smaller than the uplink frequency band, mapping the downlink RBG to the uplink RBG, wherein the mapping comprises setting a ratio of the number of downlink RBs and the number of uplink RBs so that the number of uplink RBGs is equal to the number of downlink RBGs, and mapping the uplink RBG and the downlink RBG according to the ratio and Setting an uplink RBG comprising an uplink RB in an uplink frequency, wherein each of the downlink RB and the uplink RB is transmitted through a short TTI (sTTI) which is set to be shorter than the TTI setting a downlink resource block group (RBG) comprising a downlink resource block (RB) in a downlink frequency band.A method of transmitting control information in a wireless communication system using a subframe transmitted in unit of a transmission time interval (TTI), the method comprising: