The terrestrial carrier is an OFDM QPSK signal, and cousin to WiMax and LTE, with the particular feature that more than one transmitter operates on the same frequency, forming a single frequency network. A number of transmitters can be placed around a city to create coverage that is less subject to fading than if a single transmitter were used. The satellite signal is QPSK. Both satellite and terrestrial signals have hierarchical modulation superposed on the original signal, a measure created to add bandwidth at a small expense in the satellite link budget for decoding the core audio content.