Unit 2
Modulation Technology
Text  A
Modulation Technology调制技术
Unit 2
原文：Formula (2.1) introduced the basic function of a sine wave which already indicates the three basic modulation schemes (typically, the cosine function is used for explanation):译文：公式（2.1）引入了一个基本正弦函数，它能够表示三种基本调制方案（通惯用余弦函数来说明）：