In Section 6.8 we derived the formula for the bit error rate of non-coherent binary FSK as a special case of non-coherent orthogonal modulation. In this problem we revisit this issue. As before, we assume that binary symbol 1 represented by signal S1 (t) is transmitted. According to the material presented in Section 6.8, we note the following;

The random variable L2 represented by the sample value l2 of Equation (6.164) is Rayleigh distributed.

The random variable L1 represented by the sample value l1 of Equation (6.170) is Rician-distributed. The Rayleigh and Rician distributions, using the probability distribution defined in that chapter, derive the formula of Equation (6.181) for the BER of non-coherent binary FSK.