Chirp elimination using a linearly chirped fiber grating

Gain-switched distributed feedback laser diodes (GS-DFB-LD) with high repet ition bit rate have large frequency chirp. Conventionally, the F-P spectrum filter and normal dispersion fiber were used to eliminate chirp in GS-DFB- LD pulse sources. In this paper, a new method for eliminating chirp of high repetition pulses generated from DFB laser diodes is proposed. The use of a linearly chirped fiber grating for chirp elimination is discussed theoret ically and numerically. A new apodized coupling profile function for the gr ating, which we call it the inverse Gaussian, is given. Its characteristics are analyzed and compared with other profiles. The numerical results are i n agreement with the theoretical analysis.