A Linearized Analog Photonic Link Based on a Single z-Cut LiNbO3 Dual-Output Mach–Zehnder Modulator

We propose a linearized analog photonic link (APL) using a single z-cut LiNbO
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dual-output Mach-Zehnder modulator (MZM) to remove the third-order intermodulation distortion (IMD3). A polarizer, a z-cut LiNbO
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dual-output MZM, and a polarization beam combiner are combined to realize orthogonal polarized complementary intensity modulation with diverse modulation depth. Two IMDs3 with identical amplitude and adverse phase are eliminated destructively via appropriately controlling the optical power between two orthogonal polarized paths. A theoretical analysis is carried out and demonstrated by a simulation. Simulation results show that the spurious-free dynamic range of the proposed linearized APL is 24.5 dB and 18.5 dB higher than that of the conventional optical double sideband modulation link in back-to-back transmission and after 20 km transmission in single-mode fiber, respectively. The proposed scheme features simple structure with good performance.