A digital broadcast system is provided which uses a satellite direct radio broadcast
system having different downlink modulation options in combination with a terrestrial
repeater network employing different re-broadcasting modulation options to achieve
high availability reception by mobile radios (14), static radios and portable
radios (14) in urban areas, suburban metropolitan areas, and rural areas,
including geographically open areas and geographic areas characterized by high
terrain elevations. Two-arm and three-arm receivers are provided which each comprise
a combined architecture for receiving both satellite and terrestrial signals, and
for maximum likelihood combining of received signals for diversity purposes. A
terrestrial repeater is provided for reformatting a TDM satellite signal as a multicarrier
modulated terrestrial signal. Configurations for indoor and outdoor terrestrial
repeaters are also provided.