| Fiber dispersion is one of the most holdback to upgrade today's DWDM transmission system. Due to low-cost, flexibility, low polarization dependent loss and low polarization model dispersion, Fiber Bragg grating is one of the promising compensation technologies. Based on multi-channel of sampled bragg grating (SBG) and the group delay of linear chirped fiber grating, this paper proposed and designed the blue print of SBG for multi-channel dispersion slope compensation. This paper deals with the design, fabrication and application of SBG. Simple SBG with chirp in grating period (CGP) do only compensate for multi-channel dispersion, and this paper introduces a new chirp梒hirp in sampling period (CSP). Theoretically, a SBG with CSP can be equivalent to a special SBG with CGP. In the stopbands these equivalent coefficients are varied and proportional to the Fourier order, so a SBG with CGP and CSP can compensate for the multi-channel dispersion and dispersion slope simultaneously in DWDM system. Based on the proposed concept of Moire SBG, the equivalent chirp rates of various Fourier orders in a sampled Bragg grating with chirp in the sampling period is demonstrated. A simple experiment based on stress induced sampling chirp is demonstrated to test the principle of dispersion slope compensation by SBG. Reflection and group delay spectral of uniform fiber grating exist many ripple, refractive index modulation gradient apodization is effective for reflective and group delay spectra refinement. However, the method is difficult to hold the average refractive index unity. This paper proposes and demonstrates a novel method for fabricating varied apodization-profile fiber Bragg gratings. This paper use ultra-violate laser exposure, phase mask and refractivity gradient direct writing technology to produce gratings. This paper demonstrates a 4-channel sampled grating by eximer laser. The grating compensates 695km standard single mode fiber transmission dispersion slope.
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