QAM (Quadrature Amplitude modulation) has been widely used in various digital communication systems due to its high modulation efficiency.
正交幅度调制(QAM)具有较高的调制效率，被广泛应用于各种数字通信系统中。
2
When amplitude varies, the pointer indicates the rated weight under various ranges.
当变幅时，指针指示出各种幅度下的额定起重量。
3
The ultralinear characteristics of a bistable liquid crystal electro-optic modulator and the use of it for making various special amplitude gratings and the halftone screen are introduced.