Near-Optimum Pilot and Data Symbols Power Allocation for MIMO Spatial Multiplexing System With Zero-Forcing Receiver

Power allocation between pilot and data symbols is investigated for multiple-input and multiple-output (MIMO) spatial multiplexing (SM) system with zero-forcing receiver and minimum mean square error (MMSE) channel estimation under flat block-fading channel. Based on a modified zero-forcing receiver, which takes channel estimation error into account, a new power allocation scheme to maximize the average post-processing signal-to-noise-ratio (SNR) is proposed. This scheme only requires the computation of scalars and does not need any form of channel coefficients feedback. Simulation results show that the proposed scheme outperforms simple equal power allocation with an improvement of around 3 dB and 2 dB for QPSK and 16-QAM modulations when FER = 10
^-2
, respectively.