Precoder and decoder prediction in time-varying MIMO channels

In wireless communications, mobility can make the available channel information out of date. A timely update of the channel state information is an obvious solution to improve the system performance in a time-varying channel. However, this comes at the cost of a decrease in the system throughput since many pilots have to be inserted. Thus, predicting the future channel conditions can improve not only the performance but also the throughput of many types of wireless systems. This is especially true when multiple antennas are applied at both link ends. In this paper, we propose and evaluate the performance of a prediction scheme for multiple input multiple output (MIMO) systems that apply spatial multiplexing. We aim at predicting the future precoder/decoder directly without going through the prediction of the channel matrix. The results show that in a slowly time-varying channel an increase in the system performance by a factor of two is possible.