  The probability density function (PDF) and cumulative distribution function
of the sum of L independent but not necessarily identically distributed Gamma
variates, applicable to the output statistics of maximal ratio combining (MRC)
receiver operating over Nakagami-m fading channels or in other words to the
statistical analysis of the scenario where the sum of squared Nakagami-m
distributions are user-of-interest, is presented in closed-form in terms of
well-known Meijer's G function and easily computable Fox's H-bar function for
integer valued and non-integer valued m fading parameters. Further analysis,
particularly on bit error rate via a PDF-based approach is also offered in
closed form in terms of Meijer's G function and Fox's H-bar function for
integer valued fading parameters, and extended Fox's H-bar function (H-hat) for
non-integer valued fading parameters. Our proposed results complement previous
known results that are either expressed in terms of infinite sums, nested sums,
or higher order derivatives of the fading parameter m.
