A "1" is indicated by a datapulse, occurring in the middle of the bit cell interval.
数据“1”则表示在单元间隔的中间有数据脉冲的存在。
2
These researchers were encoding digital data by varying the intensity of a pulse of light. For example, high intensity would represent a 1 and low intensity would represent a 0.
这些研究者通过改变光脉冲的强度来重编电码，比如，用高强度来表示1低强度来表示0。
3
The 4D means four data symbols (two bits), the PAM5 is Pulse Amplitude Modulation with five signal levels.