A new class of 16-ary Amplitude and Phase Shift Keying (APSK) coded
modulations, called double-ring APSK modulation, based on an amplitude
and phase shift keying constellation in which the locations of the
digital signals to be encoded are placed on two concentric rings of
equally spaced signal points. The APSK constellation parameters are
optimised so as to pre-compensate the impact of non-linearities. The new
modulation scheme is suited for being used with different coding schemes.
It is shown that, for the same coding scheme, pre-distorted double-ring
APSK modulation significantly outperforms classical 16-QAM and 16-PSK
over a typical satellite channel, due to its intrinsic robustness against
the high power amplifier non-linear characteristics. The proposed coded
modulation scheme is shown to provide a considerable performance
advantage for future satellite multi-media and broadcasting systems.