Asymptotic error analysis of diversity schemes on arbitrarily correlated rayleigh channels

Asymptotic error rate expressions are derived for multi-branch equal gain combining and selection combining operating on arbitrarily correlated Rayleigh fading channels. These closed-form solutions are used to provide rapid and accurate estimation of the error rates in large signal-to-noise ratio regions. More importantly, they reveal additional insights into the transmission characteristics of linear diversity combining schemes operating on correlated Rayleigh fading channels. It is shown that the asymptotic error rates over correlated branches can be obtained by scaling the asymptotic error rates over independent branches with a factor, det(M), where det(M) is the determinant of the normalized channel correlation matrix. This relationship is valid for both coherent and noncoherent signalings. A similar relationship is also established for the outage probabilities of fading wireless systems employing multi-branch diversity reception.