Differentially coherent fading-resistant transmission from several antennas

This paper proposes a bandwidth-efficient fading resistant transmission scheme which implements transmitter diversity using L antennas at the base station. When the antennas are spaced sufficiently far apart, the transmission from each antenna undergoes independent fading. These transmissions are coordinated to mitigate the effects of Rayleigh fading and the mobile receiver can recover the entire L-dimensional transmitted vector as long as the signal energy of at least one coordinate is large enough. L-dimensional fading-resistant signal constellations are generated by maximizing a figure of merit for the Rayleigh fading channel, assuming differential encoding and detection. This scheme offers a significant performance improvement over a conventional single-antenna differential BPSK scheme when coding is ineffective due to slow fading