Short-time Fourier transformation is widely used to expand 1 -D signal in temporal domain or spectral domain into the corresponding 2-D case in time-frequency domain. Effect of dispersion and initial chirp of pulse in fiber on signal propagation was numerically analyzed in detail by employing short-time Fourier transformation. Compared with conventional Fourier transformation, short-time Fourier transformation can more directly describe how the temporal and spectral features of optical pulse evolution vary with both dispersion and initial chirp. In addition, the evolutions of new frequency chirp induced by both dispersion and initial chirp can be clearly seen by using time-frequency analysis resulting from short-time Fourier transformation. Therefore, it completely overcomes the disadvantage of conventional Fourier transformation that is used to only compare signal transient in the spectral or temporal domain separately, and short-time Fourier transformation is expected to provide a new and effective approach to analyze the pulse propagation in fiber.%短时傅里叶变换可将1维时域或频率信号扩展到时间-频率的2维平面.为了研究了光纤中的色散效应与脉冲的初始啁啾对信号传输的影响,采用短时傅里叶变换理论进行了分析.与传统傅里叶变换相比,短时傅里叶变换可以更直观地描述光纤的色散效应与脉冲的初始啁啾如何影响信号的时域与频率的传输特性；此外,从短时傅里叶变换的时频分析图还可以很清晰地观察到在脉冲传输过程中,由色散效应与脉冲的初始啁啾所诱导的新的频率啁啾的演化规律.结果表明,短时傅里叶变换克服了传统的傅里叶变换法只能单独在频率或时域中比较信号的瞬态特性缺点,为分析光纤中脉冲信号的传输提供了一种新途径.
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