A new physical layer architecture for wavelength division multiplexing based passive optical network using orthogonal frequency division multiplexing

Abstract

In recent trends the technologies such as WDM-PON (Wavelength Division Multiplexing Passive Optical Network) are directly applied for massive deployment of several latest wide spectrum applications. The WDMPON can be considered as an ultimate solution for the next-generation access networks capable of providing unlimited bandwidth for each user. Hence, the potential WDM-PON is to be integrated and improved in order to adapt it for the next generation optical access networks and future 5G networks. The Orthogonal Frequency Division Multiplexing (OFDM) which is one of the prominent modulation formats that is being used extensively in most of the emerging broadband wired and wireless communication systems because of its effective solution to Inter-Symbol Interference (ISI) which is caused by a dispersive channel. A number of research works have established the fact that the salient features of OFDM serve as a reliable modulation format for optical communication technology. The OFDM provides a platform for interfacing a variety of wired and wireless systems and also it has made great strides in the domain of signal processing which has created an opportunity for applying the concepts of OFDM in Optical Communication. This thesis presents an extensive research on presenting an hybrid optical network combining the techniques of OFDM and WDM-PON focusing on how they are applied in the access networks. With the aid of theoretical analysis, simulations and experiments, it is shown that the system performance of OFDM for a specially generated Optical comb structure that produces the WDM-PON, is working better for both the wired and wireless connections. The properties of a dual arm Mach-Zehnder Modulator (MZM) and a single arm MZM which use a non-linear distortion are employed for the generation of the Optical comb structure. The Machine Learning (ML) techniques are also integrated in the final stages of the work for increasing the efficiency of the network which can be drastically improved by the proper selection of appropriate steps. The generation of an Passive Optical Network (PON) which supports the concepts of Radio Over Fibre (ROF) is initially generated and the Orthogonal Frequency Division Multiplexing is used as the modulation technique for the data in the generated network. The primary objective of creating such a network is to generate the maximum efficiency of the PON network by slightly changing the associated parameters. The various types of OFDM modulation techniques are tested and the Bit Error Rate (BER) values of each modulation format is noted and a comparison of all the BER values obtained help us in finding out which modulation format is best suited for PON to increase the efficiency of the network . newline