Space-Time for MIMO Multicasting and Full-Rate, Full-Diversity Codes with Partial CSI

摘要

A key contribution is an Orthogonal Space-Time Block Coding (OSTBC) scheme with max-min precoding is proposed to ensure reliable multicast transmission over MIMO channels. Compared to open-loop OSTBC and max-min beamforming, this scheme achieves universally better performance in terms of the worst-case SNR. Computational complexity reduction was achieved via a diagonal precoding scheme that can be implemented efficiently with linear programming technique and which outperforms the max-min beamforming scheme when the number of users becomes moderately large. The diagonal precoding scheme also provides a good trade-off between the mean performance and the worst-case performance. Another key contribution was a hybrid automatic repeat request (ARR) scheme for wireless multicast, i.e., common information broadcast, with incremental redundancy channel coding and packet retransmission. With this scheme, one can reliably deliver the same copy of information to different users with minimal delay. In addition, the design of the feedback channel for this scheme can be greatly simplified as no effort is required to combat cross- user interference. This work has been presented at a number of IEEE conferences and in journal papers published in the IEEE Transactions on Signal Processing, and also a book chapter emanating from the IEEE/IEE Waveform Design Workshop.