A time-domain compensation model with high IMD3 suppression for microwave photonic links

A time-domain model with high third-order inter-modulation distortion (IMD3) suppression is presented and simulated in the paper. The model can effectively compensate nonlinear distortion effects of microwave photonic links based on dual parallel Mach-Zehnder modulator (DPMZM) with double RF signals. The model results in simple exact expression for harmonic and inter-modulation components at the output of the diode detector (PD), which can be applied to the realization of microwave photonic links with high IMD3 suppression. The nonideal factors such as the electrical phase shift error of π phase shifter, amplitudes of the electrical signals applied to the electrodes of DPMZM offset to ideal values, and the half-wave voltages of sub-modulators offset to the ideal values are studied in detail. Numerical results for IMD3 suppression are well matched with the analysis ones.