Analysis of OFDM WDM using Direct Detection Technique

This paper presents Long Reach Orthogonal frequency Division multiplexing Wavelength Division Multiplexing (OFDM-WDM) system capable of delivering downstream 40 Gbit/s data. The optical source for downstream data is CW Laser at central office. We use four OFDM transmitter at central office for the 40-Gb/s downstream transmission .We have used direct detection technique for OFDM and did analysis of OFDM WDM using direct detection technique for without compensation and with compensation. We extend the maximum reach of this WDM PON to be 96 km by using Erbium-doped fiber amplifiers at the RN. Bit error rate was measured and constellation diagram observed to demonstrate the proposed scheme. In this paper Long reach and large data service aspects of a OFDM WDM is presented. The results show that the error-free transmission can be achieved for all WDM channels with sufficient power margins.