The first step in analog-to-digital encoding is called PAM. It takes analog data, sample it, and generates a series of pulses based on the results of sampling.

• 模拟-数字编码的第一步是所谓“PAM”（脉幅调制），即对模拟信号进行采样，然后生成一连串基于采样结果的脉冲。