The Performance of Multicarrier CDMA for the Correlated Rayleigh Fading Channel

We present an new method for the analytical calculation of the error probability in a Rayleigh fading channel with corre- lated fading amplitudes. Even though the method can be applied for more general problems, we restrict ourselves on the investiga- tion of a multicarrier CDMA transmission. The frequency cor- relation between the fading amplitudes of the carriers is given by the delay power spectrum of the channel. We generalize the well- known analytical expressions for the pairwise error probability of the uncorrelated Rayleigh channel to this case of correlated fad- ing. This probability can be expressed in a closed form by an in- tegral over a finite interval which can be easily evaluated numer- ically. We present some examples to show how much of the diver- sity of a code remains useful if the transmission channel does not provide an arbitrary degree of diversity.