J 1

The amplitude of the received signal on a radio link subject to fading can be adequately characterised by a random variable r. When there is no fading on the link, the amplitude of the received signal is constant and equal to A, i.e., the random variable a assumes the value A with probability 1. When there is fading in the link, r assumes values according to the Rayleigh probability density function, i.e. PED (X)= aze where D represents the event that characterises the fading occurrence and u(.) represents the unit step function. a Determine the probability density function of the random variable r. b Determine the probability of the amplitude of the received signal being less than 3, in the particular case where A = 6 and o = 1