Abstract
It has been shown from the Hurwitz-Radon theorem that square complex orthogonal space-time code designs cannot achieve full diversity and full rate simul-taneously, except in the two transmit antenna case. However, this result does not consider non-linear codes, or codes that only exist for specific symbol constellation sets. In this work, we present complex full rate codes for four transmit antennas. Using carefully tailored constellation phase rotations, we show these codes can achieve full diversity for specialized PSK and PAM symbol constellations. In addition, one code presented with PAM based symbols is a linear complex ortho-gonal design. Thus, we demonstrate by example that full rate, full diversity, square complex orthogonal codes for four transmit antennas exist when symbol constella-tions are restricted to a subset of the complex plane. This new code does not violate the Hurwitz-Radon theorem, which only considers codes that work for all possible symbol constellations.
Dalton, Lori Anne (2002). New orthogonal space-time block codes with full diversity. Master's thesis, Texas A&M University. Available electronically from
https : / /hdl .handle .net /1969 .1 /ETD -TAMU -2002 -THESIS -D332.