说明： 将复合视频、音频信号经过调制后生成的高频传输信号，主要应用于广播电视领域，接收时需经过解调将其恢复成视、音频信号。 (Will be composite video, audio signal generated by high-frequency modulated transmission signal, mainly used in the field of radio and television, when, after receiving demodulator restore into a visual, audio signal.)
