The process by which some characteristic of one wave is va ried in accordance with another wave or signal. This technique is used in modems to make business machine signals compatible with communication facilities.

• 使一种波形的某些特性按另一种波形或信号而变化的过程或处理方法。这项技术用在调制解调器里，使商用计算机的信号与通信设备的信号相兼容。