Balanced space-time block coding: an efficient way to increase diversity with feedback

Abstract

We propose full rate balanced space-time block codes which achieve full diversity for arbitrary number of transmit antennas, provided that one or a few feedback bits are sent to the transmitter denoting the relative state information of the channels. Moreover, all transmitted symbols can be decoded separately at the receiver, as in the case of orthogonal space-time block coding; thus the decoding complexity is linear. It is shown by computer simulations that the new approach provides signal-to-noise ratio improvement, and it is more resilient to feedback errors, compared to the transmit antenna selection technique, on the basis of same number of feedback bits.