Performance analysis of extended RASK under imperfect channel estimation and antenna correlation

Spatial modulations (SM) use the index of the transmit (or the receive) antennas to allow for additional spectral efficiency in MIMO systems by transmitting spatial data on top of classical IQ modulations. Extended Receive Antenna Shift Keying (ERASK) exploits the SM concept at the receiver side and yields the highest overall spectral efficiency in terms of spatial bits compared to the conventional SM schemes. To perform efficiently, ERASK may use zero-forcing precoding to target spatial streams towards the selected receive antennas, therefore requiring the Channel State Information CSI at the transmitter. In this paper, we evaluate the theoretical performance degradation of the ERASK scheme under imperfect CSI. In addition, correlation between antennas at the transmitter and the receiver using the Kronecker correlation model is integrated in our analysis. Analytical approach for the Bit Error Rate performance is provided and validated through simulations.