Effect of imperfect channel estimation on the performance of selection combining in Rayleigh fading channels

The paper presents a general analysis on the performance of selection combining (SC) systems in Rayleigh fading channels with imperfect channel estimation (ICE). The channel estimate and the actual fading are modeled as complex joint Gaussian random variables. Simple single integral formulas with finite integration limits are derived for the symbol error probability (SER) of an arbitrary two-dimensional (2D) modulation format, and a closed-form expression is obtained for the SER of M_s-PAM. These error probability expressions are then applied to three types of channel estimation errors possibly encountered in practical systems to study their impact on the performance of selection diversity. Other applications of this general analysis include semi-analytical simulation of practical communication systems.