SIMULATION AND EXPERIMENTAL INVESTIGATION OF MITIGATION OF FWM EFFECTS IN FRONTHAUL TRANSMISSION SYSTEM

Abstract

Over the recent years, the need for high capacity and high broadband wireless access were in demand and in order to satisfy it various technologies were intro duced among which RoF came into existence which has low attenuation, immunity to electromagnetic interference and superior signal integrity. Therefore, it enables the transmission of signal over long distance and thus improves the capacity and mobility of the optical transmission system. In this review, we would concentrate on analyz ing the effect of fiber nonlinearity such as Four wave mixing (FWM) effect in long haul transmission system. Basically, FWM is an impairment due to the interaction of field intensity with the fiber refractive index which results in signal broadening, undesirable signal modulation and attenuation and thereby limiting the transmission capability of long-haul system. A parametric analysis for reducing the power level of crosstalk generated by FWM by incorporating various optical components in the communication link is done and optimization based on channel spacing, input power, fiber length, bitrate, is performed. This article discusses the nonlinear effect, four-wave mixing (FWM), which lowers the performance of optical communication systems. The concept of Linear polariza tion was introduced to reduce the effects of FWM. Here, orthogonal polarization is used with the modulation technique NRZ. Linear polarization was found to reduce the effect of FWM more than round polarization. Weaknesses of the four wavelength mixes were analyzed for various levels of input power. The capacity of a four-wave mixing product (FWM) is assessed by an optical spectrum analyzer. System perfor mance is analyzed in terms of quality factors and BER.