'Institute of Electrical and Electronics Engineers (IEEE)'
Doi
Abstract
This paper considers the optimization of transceivers
with decision feedback equalizers (DFE) for slowly time-varying
memoryless multi-input multi-output (MIMO) channels. The data
vectors are grouped into space-time blocks (ST-blocks) for the
spatial and temporal precoding to take advantage of the diversity
offered by time-varying channels. The space-time generalized
triangular decomposition (ST-GTD) is proposed for application
in time-varying channels. Under the assumption that the instantaneous
channel state information at the transmitter (CSIT) and
receiver (CSIR), and the channel prediction are available, we also
propose the space-time geometric mean decomposition (ST-GMD)
system based on ST-GTD. Under perfect channel prediction, the
system minimizes both the arithmetic MSE at the feedback detector,
and the average un-coded bit error rate (BER) in moderate
high signal to noise ratio (SNR) region. For practical applications,
a novel ST-GTD based system which does not require channel
prediction but shares the same asymptotic BER performance
with the ST-GMD system is also proposed. At the moderate high
SNR region, our analysis and numerical results show that all
the proposed systems have better BER performance than the
conventional GMD-based systems over time-varying channels;
the average BERs of the proposed systems are non-increasing
functions of the ST-block size