Research On Light-oscillograph Calibration Specification And The Eye-diagram Calibration Module

With the fast development of optical fiber communication technologies, the data transmission rate has become higher and higher. And the transmission accuracy is also improved rapidly. A light-oscilloscope can be used to inspect the communication signal quality. Therefore it is of important to know whether the light-oscilloscope is normal or not. For inspection of the light-oscilloscope, a calibration specification is needed and for calibration of its eye-diagram, a kind of calibration module is also needed. Aiming at the two problems, a light-oscilloscope calibration specification is researched and an eye-diagram calibration module is designed. The main content is as follows:(1) After researching all important characteristic parameters of light-oscilloscope, some capability parameters are put forward. They are divided into two groups according to their importance degree. One group includes 11 mandatory parameters and the other includes 5 optional parameters for quick or general calibration respectively. On the base of the parameters'definition and instruments performance level, the measurement and calibration method of these parameters are put forward and the calibration specification is established.(2) According to all parameters of light-oscilloscope, a calibration module for eye-diagram is devised. This module includes signal generator, shaping circuit, laser, laser driver, automatic temperature controller, automatic power controller, laser protector and electrical source.(3)The influence factors, problems and resolve methods of every part of the calibration module are analyzed. Then a calibration module is designed on the bases of MAX3735A and AND8830.The results of research and experiment show that the light-oscilloscope calibration specification and the eye-diagram calibration module meet the current demand.