Optical space domain reflectometry (OSDR) for determination of strength and chirp distribution along optical fiber gratings

Fiber gratings are primarily characterized by the distribution of grating strength and chirp along the structure. These properties are comprised in the complex coupling coefficient κ(z). Whilst for simple fiber gratings used in simple applications the ability to determine the complete, complex distribution of the coupling coefficient κ(z) may be of secondary importance, it is useful and sometimes mandatory for evaluating more complicated designs, e.g. those based on localized phase shifts to create transmission windows in the stop band, Fabry-Perot structures, dispersion compensating gratings etc.