A Novel Design of Bidirectional WDM-PON by using Mode Locked Laser and RSOA

This paper presents Long Reach Wavelength Division Multiplexing Passive Optical Network (WDM-PON) system capable of delivering downstream 40 Gbit/s data and upstream 40 Gbit/s data on a single wavelength. The optical source for downstream data and upstream data is mode locked laser at central office and reflective semiconductor optical amplifier (RSOA) at each optical network unit. We use four RSOAs at each optical network unit for the 40-Gb/s upstream transmission. The operating wavelengths of these RSOAs are separated by the free-spectral range of the optical demultiplexer at the central office and remote node (RN) for demultiplexing the WDM channels. We extend the maximum reach of this WDM PON to be 117 km by using Erbium-doped fiber amplifiers at the RN. Bit error rate, were measured to demonstrate the proposed scheme. In this paper Long reach and large data service aspects of a WDM-PON is presented. The results show that the error-free transmission can be achieved for all WDM channels with sufficient power margins.