Linear Receivers for Spectrally-Precoded MIMO-OFDM

A multi-input multi-output orthogonal frequency division multiplexing system using spectral precoding to reduce out-of-band power emission is considered. For single-antenna systems, existing spectral precoders that maintain the transmission rate cannot be linearly inverted, calling for iterative interference cancellation receivers. In this letter, it is shown that such spectral precoders when combined with a multiple-antenna transmission can allow a well-defined zero-forcing equalization. Numerical results show that the proposed receivers can achieve close-to-optimal performance as well as reduced complexity in the large antenna array regime.