Abstract:This paper presents an approach to calculate dispersion penalty for VSR-1 optical links. Based on parameters of a specific VSR-1 link, dispersion penalties are computed for various modal dispersion bandwidths respectively. The worst-case eye closure is expressed numerically by using the signal waveform at time 0, and the signal waveform is obtained in frequency domain through FFT algorithm. By this approach,the dispersion penalty is determined by the shape of transfer functions of the various components in the links. To simplify the derivation of multimode fiber link transfer function,a Gaussian form of normalized impulse response is used. This calculation approach can be used to estimate the worst-case dispersion penalty of VSR-1 links in the link budget analysis.