Comparative Analysis of Symbol Error Probability Estimation Techniques for Wireless Fading Channels

One of the most important components in the field of developing wireless communication systems is the assessment of symbol error probability (SEP). A precise evaluation of SEP, especially in fading channels, requires the calculation of the Gaussian Q-function and correct approximation of functions such as erf(.), erfc(.), and Q(.). Here, a composite technique is shown that reveals tighter exponential bounds for the Gaussian Q-function, greatly improving the average SEP evaluation over fading channels. When compared to current Gaussian Q-function approximations, this composite framework is more mathematically straightforward and is effective at handling a wide range of signal-to-noise ratios. Further-more, SEP integrals for Nakagami-m fading channels are studied analytically for a range of fading parameter values in the rectangular QAM (R-QAM) and the conventional non-rectangular quadrature amplitude modulation (QAM) scenarios. This thorough investigation confirms the need of accurate Q-function approximations in system performance analysis and advances our knowledge of SEP estimate techniques in wireless fading channels.