... This paper then investigates the FWM penalties imposed on DWDM systems based on G. 652, G. 653, and G. 655 fibers, considering equally spaced channel grids of 100, 50, 25, and 12.5 GHz. Also, the ... based on DSF fibers. .Keywords DWDM systems, Four-Wave Mixing (FWM) , G. 652, G. 653, G. 655 compliant fibers, Signal-to-noise ratio. I. INTRODUCTIONENSE wavelength-division-multiplexing (DWDM) ... analysis of the penalties imposed by the FWM phenomenon on WDM systems using G. 652, G. 653, G. 655 compliant fibers, in the specific context of the ITU-T Recommendations G. 692, and G. 694.1,...