Point-to-Point Transmission over MIMO Channels with Intersymbol Interference: Comparison of Single- and Multicarrier Modulation

Two basic concepts for point-to-point transmission over multiple-input/multiple-output channels with intersymbol interference (MIMO ISI channels) are reviewed and compared. The approaches can be characterized by the way how they deal with multiuser (spatial equalization) and intersymbol interference (temporal equalization). In MIMO orthogonal frequency division multiplexing, temporal equalization is performed by applying OFDM, which decomposes the MIMO ISI channel into a set of independent flat fading MIMO channels. For each of this parallel channels (the carriers), spatial equalization, e.g., via V-BLAST, is performed individually. Conversely, in MIMO decision-feedback equalization both types of interferences are treated jointly. The advantages and disadvantaged of both strategies are enlightened, and results from numerical simulation are shown. The paper reveals under which conditions both strategies exhibit the same performance.