MIMO-OFDM system for increasing reliability

A MIMO-OFDM system for increasing reliability comprising:

• a transmission terminal that includes Nt transmission antennas and transmits a MIMO signal through relay terminals;
• and
• a reception terminal that receives the MIMO signal from the relay terminal through Nr reception antennas,
• wherein the transmission terminal extracts a composite channel coefficient from a composite channel generated by matching a channel between the transmission terminal and the reception terminal with a channel between each of a plurality of the relay terminals and the reception terminal, selects the relay terminal corresponding to the composite channel coefficient having a maximized channel capacity from among the plurality of relay terminals by using the extracted composite channel coefficient, and transmits a MIMO signal to the reception terminal through the selected relay terminal,
• wherein the transmission terminal includes:
• a communication unit that estimates the composite channel by respectively transmitting pilot signals to the plurality of relay terminals;
• a singular value extraction unit that acquires information on a channel matrix by using the estimated composite channel and extracts a singular value by applying a singular value decomposition (SVD) method to the channel matrix;
• a composite channel coefficient calculation unit that calculates the composite channel coefficient by using the extracted singular value;
• and
• a relay terminal selection unit that calculates a channel capacity by using the calculated composite channel coefficient and selects a relay terminal having a maximum value among the calculated channel capacities from among the plurality of relay terminals.