Optimal length of the training and data phase in continuous flat fading MIMO channels

In this paper, we investigate the optimal length of the training and data phase for continuously time-varying channels that maximize the achievable information rate. It is shown that both lengths depend not only on the Doppler spread of the channel but also on the noise power and the number of transmit antennas whereas the number of receive antennas and the channel condition have only a small influence. It turns out that the optimal coherence interval depends strongly on the SNR, whereas the optimal ratio between training and data phase is nearly independent on the SNR.