Abstract--This paper investigates the field of implementation of communication systems with field programmable gate arrays (FPGA). A new scheme based on a multiple input multiple output-orthogonal frequency division multiplexing (MIMOOFDM) system is presented leading in great FPGA resources saving. Classical MIMO-OFDM scheme uses a space-time block coder (STBC) and one OFDM modulation per transmit antenna. Our contribution deals with a customized space-time block coder (CSTBC) and only one classical OFDM modulation whatever the number of transmit antennas is. Classical and new schemes are analytically equivalent. Implementation of MIMO systems with two transmit antennas and four transmit antennas is discussed.