Implementation methods for all-optical OFDM system

Orthogonal frequency division multiplexing (OFDM) is an efficient multiplexing/demultiplexing technique studied and developed over several years to accommodate the rapid growth in communication networks. OFDM was recently entered the optical communication field due to its promising features, especially in the optical domain such as high data rate, high spectral efficiency, immunity against dispersion, and improving the received signal. OFDM is classified into three categories based on implementation process of fast Fourier transform (IFFT/FFT) these categories are electrical OFDM, Optical OFDM (O-OFDM), and all-optical OFDM (AO-OFDM). From O-OFDM to AO-OFDM various methods existed to accomplish them. This paper investigated optical OFDM in general case and deeply focused on all-optical OFDM by highlighting on the various techniques existed to implement it until now, comparing between these methods in terms of multiplexing/demultiplexing and concluded the best method to implementing AO-OFDM.