Simulations of modulator nonlinear effects in radio-over-fibre systems

We propose the use of optical frequency multiplication as a cost-effective method to optically generate wireless radio frequencies (RFs) and deliver them from a central station to remote radio access units. Mach-Zehnder modulators (MZMs) are employed to transport the RF data. We focus on the impact of the nonlinearity of MZMs on the radioover-fibre system performance for single-carrier and orthogonal frequency division multiplexing (OFDM) formatted data. A larger system penalty is shown in the OFDM RoF system due to a more severe nonlinear cross-talk effect between sub-carriers, compared with the single carrier system.