Multiple Channels Per Carrier (MCPC)

Analog signals, such as those used by satellite TV and terrestrial microwave-relay communications, depend on subcarriers. MCPC technology modulates analog signals as signals with higher frequencies and bandwidth. Subcarriers are transmitted with video carrier signals on a satellite transponder at frequencies of 5.8 MHz, 6.2 MHz or 6.8 MHz with extra audio at 7 MHz or 8 MHz, as needed. These are the MCPC transmissions, and the satellites involved are known as MCPC satellites.

By 2011, MCPC technology was largely replaced by digital TV, which multiplexes audio and video data as a single Moving Picture Experts Group (MPEG) transport stream. This process involves streaming multiple video signals from film, sports and news broadcasts, as well as multiplexing data as a single transport stream, which is directed to a large antenna. This antenna broadcasts the stream to a TV with an Advanced Television Systems Committee (ATSC) tuner that receives and decodes signals for screen display.