Carrier system

In telecommunication, a carrier system is a multichannel telecommunications system in which a number of individual circuits (data, voice, or combination thereof) are multiplexed for transmission between nodes of a network.

Note 1: In carrier systems, many different forms of multiplexing may be used, such as time-division multiplexing and frequency-division multiplexing.

Note 2: Multiple layers of multiplexing may ultimately be performed upon a given input signal; i.e., the output resulting from one stage of modulation may in turn be modulated.

Note 3: At a given node, specified channels, groups, supergroups, etc., may be demultiplexed without demultiplexing[?] the others. Synonym (loosely) carrier.

Source: from Federal Standard 1037C and from MIL-STD-188