A Multiple Input Multiple Output (MIMO) single carrier wireless communication system is provided. The system includes a coder for performing block coding on symbols, an extender for collecting the block-coded symbols during one transmit (Tx) signal duration and for performing repetitive extension on the collected symbol vectors by an interval required in a frequency domain, an inserter for inserting ‘0’ to the repetitively extended symbol vectors so that the vectors are mutually orthogonal in a time domain, and a combiner for multiplying the ‘0’-inserted symbol vectors by a phase component so that the vectors are mutually orthogonal in the frequency domain and thereafter for combining the symbol vectors to generate a Tx signal for each antenna.