Generation and Comparison of Filterless Octuple RoF Upconversion Systems Based on Cascaded and Dual Parallel MZM Configuration

Abstract

In this manuscript, Octuple RoF upconversion systems based on dual parallel Mach–Zehnder modulator (MZM) configuration (PMC) and Cascaded MZM configuration (CMC) have been generated and compared. Modulation index and bias points of both MZMs and phase of local oscillator (LO) Radio frequency (RF) are properly optimized for generation of 80 GHz upconverted electrical signal from a 10 GHz RF drive signal. The effect of RF drive signal frequency on optical sideband suppression ratio (OSSR) and RF spurious sideband suppression ratio (RFSSR) is evaluated. Mm-wave signal tunability from 8 to 80 GHz is investigated by applying RF drive signal from 1 to 10 GHz. It is worth to mention here that no optical filter is required in both schemes to obtain mm wave signal of high spectral purity, hence leading to reduction in the system cost and complexity.