“…Each CR senses a PU and sends sensing information (energy) without performing local decision to the FC via reporting channels. The signal received at CR, , can be written as In [3], the expressions of an average , for a single CR are derived under and channels. The expression of each SLS, SLC, MRC, and SC scheme in AWGN channels is given in [5], and an average , for a given SDF scheme can be derived as where is the probability density function of …”