CLOCK EXTRACTING APPARATUS USING OPTICAL FILTER AND METHOD THEREFOR

摘要

PURPOSE: A clock extracting apparatus using an optical filter and a method therefor are provided to extract a clock from a data signal by reducing noise components and economically extracting a spectral line component. CONSTITUTION: A circulator(510) changes a path of an optical signal, and prevents optical signals reflected from the first filter(520) and the second filter(530) from being mixed with a different signal. The first filter(520) reflects a side peak, and extracts a spectral line corresponding to the second side peak. The second filter(530) reflects a wavelength corresponding to a peak, and extracts a spectral line corresponding to the peak. An attenuator(540) makes optical strengths of extracted spectral lines the same. A photodiode(550) receives frequency signals of two spectral lines having the same optical strength and generates a beating phenomenon to extract a clock component.