  A hierarchical modulation method is proposed for providing local content in a
hybrid satellite and terrestrial single frequency network such DVB-SH. The
hierarchical modulation is used to transmit both global and local content in
terrestrial transmitters. The global content is transmitted with high priority
layer of the hierarchical modulation, and the local content is modulated with
the low priority layer of the hierarchical modulation. The satellite transmits
global content only. The performance of the hierarchical system for both global
and local content is analyzed.
