The degree of polarization (DOP) is one of the physical quantities to describe fentures of light beam
its measurement is of great importance. In this paper
the principle and realization of DOP measurement using polarimetric method
scrambling method and extrema search method are analyzed in detail. The advantages and disadvantages of every methods are also given. The difference between two formulae for calculating DOP is discussed. And a DOP measurement scheme with high speed and accuracy applicable to polarization mode dispersion (PMD) compensation system is presented.