subcarrier

A subcarrier is a low-frequency carrier used in electronic systems, such as telemetering or multichannel radio systems. It modulates a main carrier and can itself be modulated to carry information.1

In frequency-division multiplexing, multiple messages are transmitted simultaneously over a single path. Each message is assigned a unique subcarrier frequency. These subcarriers are then combined to modulate a main carrier frequency. At the receiving end, the original messages are recovered by separating the subcarriers based on their frequencies. This allows for the efficient transmission of several signals at once.2