Error probability of fading channel

Rayleigh Fading channel
 For a fixed attenuation α, the error rate of binary PSK as a fuction of the received SNR γb is  
                           
                               Pb(γb)=Q(sqrt(2*γb))

The expression for the error rate of binary  FSK is given by equation as

                              Pb(γb)=Q(sqrt(γb))
where γb=α^2*Eb/No

When α is Rayleigh-distributed, we must average Pb(γb) , therefore the probability density function of γb must be evaluated by the integral function

The result of this integration for binary PSK is

and the probability of error for binary FSK in the form  that shown in below