Method for transmitting a midamble in a radio communication system

A method for receiving multiple input multiple output (MIMO) midambles in a radio communication system, the method comprising:

• receiving, from a base station, radio resource information regarding a radio resource to which the MIMO midambles of multiple antennas are allocated in a carrier;
• and
• receiving the MIMO midambles from the multiple antennas of the base station on the radio resource recognized from the radio resource information,
• wherein the MIMO midambles includes sequences for distinguishing each of the multiple antennas of the base station such that a channel estimation for each of the multiple antennas is possible,
• wherein the carrier includes a plurality of resource units, each of which includes a plurality of subcarriers in a frequency domain and a plurality of orthogonal frequency division multiplexing (OFDM) symbols in a time domain,
• wherein a resource element is defined as one subcarrier in the frequency domain and one OFDM symbol in the time domain,
• wherein the carrier includes a used band including subcarriers allocated for transmitting a signal and a guard band including subcarriers allocated for preventing interference from occurring in the used band, and the MIMO midambles are allocated within the guard band, and
• wherein the MIMO midambles are allocated to resource elements within the guard band, except for resource elements used for transmitting pilot signals for a channel estimation.