Unitary Space-Time Modulation for Single-Carrier Transmission Over Frequency-Selective Channels

Space-time modulation exploiting diversity or/and coding gains has been a major focus in high-speed wireless communications systems against channel fading. We employ noncoherent space-time modulation in cyclic-prefix (CP) based single-carrier (SC) block systems over frequency selective Rayleigh block fading channels, where channel order, upper-bounded by the CP length, is assumed known. Capitalizing on multi-channel input-output relation for time-domain processing, we reveal that employing complex orthogonal m-sequences can enable a simplified maximum-likelihood (ML) detector. Further, code construction is addressed so as to adaptation of a variety of transmission rates and trellis-coded unitary space-time modulation is also investigated. Numerical results suggest that this noncoherent space-time modulation for SC block system, coupled with time-domain ML detection, can realize multipath diversity under certain circumstances.