  The recently proposed Fluctuating Two-Ray (FTR) model is gaining momentum as
a reference fading model in scenarios where two dominant specular waves are
present. Despite the numerous research works devoted to the performance
analysis under FTR fading, little attention has been paid to effectively
understanding the interplay between the fading model parameters and the fading
severity. According to a new scale defined in this work, which measures the
hyper-Rayleigh character of a fading channel in terms of the Amount of Fading,
the outage probability and the average capacity, we see that the FTR fading
model exhibits a full hyper-Rayleigh behavior. However, the Two-Wave with
Diffuse Power fading model from which the former is derived has only strong
hyper-Rayleigh behavior, which constitutes an interesting new insight. We also
identify that the random fluctuations in the dominant specular waves are
ultimately responsible for the full hyper-Rayleigh behavior of this class of
fading channels.
