Broadcasting systems have to deal with channel diversity in order to offer
the best rate to the users. Hierarchical modulation is a practical solution to
provide several rates in function of the channel quality. Unfortunately the
performance evaluation of such modulations requires time consuming simulations.
We propose in this paper a novel approach based on the channel capacity to
avoid these simulations. The method allows to study the performance in terms of
spectrum efficiency of hierarchical and also classical modulations combined
with error correcting codes. Our method will be applied to the DVB-SH standard
which considers hierarchical modulation as an optional feature.Comment: To appear in WTS 2011 proceeding