Transmit and Receive Weights in Vector Coding with Channel Estimation Error and Feedback Delay

Abstract

Vector Coding (VC) is a transmission scheme that can obtain path diversity gain while orthogonalizing multiple symbols. It has been shown that VC can provide good bit error rate (BER) performance compared to orthogonal frequency division multiplexing (OFDM). In addition VC has been proven to be the optimal partition of time domain channel. However, In VC, the eigenvectors of the channel matrix must be available at both transmitter and receiver. Thus, orthogonalization and path diversity gain can be achieved only if perfect channel state information (CSI) is available at both ends. However, there exists channel estimation error in practice. In addition feedback delay of estimated CSI causes mismatch of CSI at both ends, which degrades the performance of VC severely. To see the feasibility (implementability) of VC, it is very important to evaluate the effects incurred by channel estimation error and feedback delay on the performance of VC. In this paper, we analyze VC system in the presence of channel estimation error and feedback delay. We show how the transmit and receive weights selection affects the performance of VC. Numerical (Theoretical) results are confirmed by computer simulations.