According to one embodiment, a user equipment for use in a mobile communication system is configured to: receive control information including a first field and a second field via a control channel, the first field indicating one of N (N≧2) resource block group (RBG) sets and the second field including a bitmap, wherein each bit of the bitmap is used to indicate whether a corresponding resource block (RB) in the indicated one of the N RBG sets is allocated; interpret the first field and the second field for resource allocation in the control information; and receive data using the control information. An RBG set n (0≦n