Fatemeh Dehghani - Optoelectronic Research Center, Electronic Department of Shiraz University of Technology.
Farzin Emami - Optoelectronic Research Center, Electronic Department of Shiraz University of Technology

Data transmission in optical systems and increased transmission distance capacity benefit by using optical amplification wavelength division multiplexing (WDM) technology. The combination of four waves (FWM) is a non-linear effect in the wavelength division multiplex (WDM), when more than two wavelengths of light in a fiber launch will occur. FWM amount depends on the channel, the channel spacing and dispersion fiber, but is independent of the bit rate. A simple equation for the spectral line width is shown. Dispersion causes distortion of the transmitted signals and needs to be compensated to achieve a long-haul system. The four-wave mixing effect have been studied as one of the factors influencing by using OPTISYSTEM Software. In this paper, a new approach for suppressing the four-wave mixing (FWM) crosstalk by using the pairing combinations of differently linear-polarized optical signals is investigated. The simulation is conducted using an eight-channel system. The proposed technique is to suppress the FWM interaction using different input powers. It has been evaluated for single-mode fiber (SMF). FWM can be strongly reduced, when the polarization technique is conducted for SMF. We also compare our new method with a conventional method to demonstrate the effect of FWM as well. The comparison was conducted at an input power range of ۲ dBm. Decreasing the input power can decrease the FWM effects. In the absence of the polarization technique the FWM power was –۶۴ dBm at an input power of ۲ dBm. The FWM power decreased to less than -۸۲ dBm at a ۲ dBm input power. The system performance greatly has been improved.

four wave mixing, linear polarization, wavelength-division-multiplexing, dispersion