1. A method for performing Forward Error Correction (FEC) in a Multiple-Input Multiple-Output (MIMO) communication system using a Turbo-Bell Labs Layered Space-Time (BLAST) scheme, the method comprising: performing soft decision on a frame received via a plurality of antennas; performing iterative decoding on a soft decision result value a predetermined number of times, and outputting Log Likelihood Ratio (LLR) values for information bits and first parity bits constituting the frame; generating second parity bits by coding information bits calculated from the LLR values, and comparing the first parity bits calculated from the LLR values with the coded second parity bits; and if the first parity bits are identical to the second parity bits, outputting the information bits, determining that there is no error, and if the first parity bits are not identical to the second parity bits, feeding back the LLR values as a-priori information of the soft decision, and returning to the performing of soft decision.