Lower Bound on Probability of Error of Alamouti St-Coded OFDM Systems with Frequency Offset

Abstract

In this paper, we analyze the lower bound on the error performance of space-time coded (Alamouti-coded) orthogonal frequency division multiplexing (OFDM) systems with carrier frequency offset (CFO) in a Rayleigh fading channel. It is shown that the frequency-flat fading causes the maximum correlation between the signal and the inter-carrier-interference (ICI) noise power. This channel scenario provides the lower bound on error performance. A semi-analytical procedure of calculating the symbol error probability (SEP) lower bound based on post-equalized signal-to-interference-and-noise ratio (SINR) distribution is provided. This procedure covers both M-PSK and M-QAM modulation schemes. The numerical results demonstrate the accuracy of the expressions derived for SEP lower bound.