a) The modulation sidebands of the color subcarrier contain the R-Y and B-Y information. For NTSC, the subcarrier frequency is 3.579545 MHz. For PAL the subcarrier is approximately 4.43 MHz. b) An auxiliary information carrier added to the main baseband signal prior to modulation. The most common example in television is the NTSC color subcarrier.

Many ATV schemes propose adding additional subcarriers to NTSC.

c) A sine wave which is imposed on the luminance portion of a video signal and modulated to carry color information. Subcarrier is also used to form burst. The frequency of the subcarrier is 3.58 MHz in NTSC and PAL-M and 4.43 MHz in PAL. d) The high-frequency signal used for quadrature amplitude modulation of the color difference signals.