中文说明：
FM（Frequency Modulation）即调频，习惯上用FM来指一般的调频广播（76-108MHz，在中国为87-108MHz、日本为76-90MHz），事实上FM也是一种调制方式。
English Description：
FM (frequency modulation) is frequency modulation. It is used to refer to general FM broadcasting (76-108mhz, 87-108mhz in China and 76-90mhz in Japan). In fact, FM is also a modulation mode.