眼图用于测试数字传输信道质量。由于传输过程中的频带限制，噪声的叠加使得1和0的差别变小。在接收机的判决点，将“1”和“0”的差别用眼图上“眼睛”张开的大小来表示，十分形象、直观和实用。

首先产生一个二进制随机方波序列，通过升余弦滤波器滤波后，方波的高频成分滤掉后绘出的眼图。在程序中形成在Workspace中的数据变量D。通过指令sim（‘eye’）将工作空间的数据D馈送到眼图仪EyeDiagram，得到眼图仪显示的眼图（右图）。-Eye for testing the quality of digital transmission channel. Since the transmission band limit superimposed noise makes the difference between 1 and 0 becomes smaller. At decision point receiver, the　1　and　0　differences with the eye　eyes　to represent the size of the opening, the image is very intuitive and practical.

First generate a random binary sequence of square wave, filtered through a raised cosine filter, filter out high frequency components of the square wave after drawn eye. Data variables in the program formed in the Workspace in D. By instruction sim (　eye ) workspace data D fed to the eye instrument EyeDiagram, get eye instrument display eye diagrams (right).