SVD-Based Frequency Domain Equalizer for MIMO-CDMA Systems Using Virtual Antennas

This paper proposes a new approach to apply singular value decomposition (SVD) in fractionally spaced frequency domain equalizer (FSFDE) for the single carrier MIMO-CDMA systems. Multiple data streams can be reliably transmitted through the parallel subchannels by using SVD, which can improve the capacity effectively without increasing frequency bandwidth or the average transmit power. Fractional sampling at the receiver is equivalent to having multiple virtual receive antennas with correlated channel gains and colored noise, which may be seen as a virtual receive diversity. Therefore, each polyphase component is denoted as a virtual antenna, and it is also called fractionally spaced system as virtual antennas system. Simulations show that high performance can be achieved by using SVD with virtual antennas.