On the performance of space-time codes with transmit correlation

In this work, we analyze the pairwise error probability (PEP) performance of space-time codes in the presence of transmit fading correlation. Unlike receive correlation, the effect of transmit correlation depends on the specific space-time code used. We show that at low SNR, depending on the code, transmit correlation can either improve or degrade the PEP performance. By analyzing the worst case scenario for asymptotically high or low SNR, we show that, to guarantee robust performance for arbitrary transmit correlation, the minimum eigenvalue of the codeword pair difference matrix should be maximized among all codeword pairs. Numerical and simulation results are given to corroborate the theoretical analysis.