The main objective of this paper is to analyze the Four Wave Mixing efficiency (FWM) for different fiber lengths and channel spacing and nonlinear Schrödinger equation solution. In this document, we have simulated the FWM design for two and three waves. We have also analyzed the influences of non-linear refractive index on the four-wave mixing (FWM) characteristics in Semiconductor Optical Amplifiers (SOAs).It has been shown that the generated FWM signal characteristics can be modified due to the variation of non-linear refractive index of the SOA's medium. The wave propagation in the SOA has been modeled using the nonlinear Schrodinger equation. Simulation of Schrödinger equation is carried out using split step Fourier method. The FWM design was simulated with the OPTSIMv5.0 tool and analyzed using the eye pattern method with respect to bit error rate and Q factor. In this paper, FWM efficiency is analytically simulated for two wave and three wave fiber transmission. The results obtained show that the efficiency decreases with the increase of both the frequency spacing and the fiber length, which can be explained using the phase-matching condition. All the efficiency and power equations have been numerically simulated in MATLAB.