By using gain saturation effect of Semiconductor Optical Amplifier along with optical delay line we propose the scheme for generation of doublet pulse, which is equivalent to second order derivative of Gaussian pulse. Obtained IR-UWB doublet pulse should satisfied the condition instructed by FCC, to avoid the interference with other narrowband or impulse communication and by using proposed scheme we achieve it. Various modulation approach results in variation in output. In this paper we observe the change in output with respect to change in change in SOA current, Delay line values and attenuator used before to SOA. All these change we observed in terms of Q-factor and minimum BER values by using opti-system software. Keywords- IR-UWB, SOA, MZM, ODL,Q-factor, BER.