A General Moment Generating Function for MRC Diversity over Gaussian Gain Fading Channels

For maximal ratio combining (MRC) diversity over correlated fading channels with Gaussian channel gains, we utilize unitary diagonalization to decorrelate the physical channels into uncorrelated virtual channels to easily obtain the moment generating function (MGF) of the received signalto-noise ratio (SNR). The MGF thus obtained has a compact form and can be universally applied to various popular fading models. In addition to the advantage of simple derivation procedure, this general MGF can be readily modified to express various scenarios of channel power distributions as well as joint fading models. To demonstrate these advantages, we compare our derivation and our MGF expression for the generalized Ricean fading case with an existing work in the literature.