Methods and apparatus are provided for the provision of high definition television services over an analog or digital broadcast infrastructure. In one aspect, the present invention provides a method for transmitting a plurality of digital data streams over an analog microwave link comprising multiplexing the digital data streams, converting the multiplexed data stream into an analog baseband signal and transmitting the baseband signal along with an analog sub-carrier over an analog broadcast network. In another aspect, an apparatus for performing the method is provided. In a further aspect, a method and apparatus for preparing digital data for transmission over a microwave link comprises the step of, or structure for, multiplexing a plurality of digital data streams, encoding the multiplexed digital data stream to form a multi-level signal and combining the multilevel signal with one or more sub-carrier signals to form a radio frequency signal.