Linearized analog photonic links based on a dual-parallel polarization modulator

Abstract

A linearized analog photonic link (APL) is proposed based on an integratable electro-optic dual-parallel polarization modulator (DPPolM), which consists of two polarization beam splitters and two polarization modulators (PolMs). Theoretical analysis shows that the APL is potentially free from the third-order nonlinear distortion if a polarization controller placed before the DPPolM is carefully adjusted. A proof-of-concept experiment is carried out. A reduction of the third-order intermodulation components as high as 40 dB and an improvement of the spurious-free dynamic range as large as 15.5 dB is achieved as compared with a single PolM-based link. The DPPolM-based APL is simple, compact, and power efficient since it requires only one laser, one modulator, and one photodetector.

A single sideband radio-over-fiber system with improved dynamic range incorporating a dual-electrode dual-parallel Mach–Zehnder modulator

“…Some research works of optic single sideband (OSSB) ROF systems based on MZM eliminate the second-order and high-order harmonic components, which suppresses the nonlinearity of the ROF system effectively but they do not analyze the effect of third-order intermodulation distortion (IMD3) on the system's nonlinearity [3][4][5][6]. There are also schemes proposed to suppress the IMD3 to improve the SFDR, but they are all aimed at double sideband (DSB) ROF [7][8][9][10][11]. Considering that the single sideband (SSB) signal has advantages in remote transmission, we propose a novel ROF scheme by eliminating the IMD3 to improve the SFDR on the basis of analyzing the theory of IMD.…”

Linearization of an intensity-modulated analog photonic link using an FBG and a dispersive fiber

“…Numerous techniques based on external modulation have been proposed in recent years to improve the SFDR of APLs, such as the schemes based on two parallel MZMs [2,3] or PolMs [4], two cascaded MZMs [5] or PolMs [6]. The main ideas of these schemes are to cancel out the third-order intermodulation distortion (IMD3) terms generated from the two modulators by properly setting the transmission points, the input optical power ratio and/ or the modulation index (MI) ratio of the two modulators.…”

Dynamic-Range Enhancement for a Microwave Photonic Link Based on a Polarization Modulator

“…The bandwidth can be significantly increased if linearization is implemented in the optical domain. Numerous optical techniques have been proposed, including low biasing an MZM to partially suppress the optical carrier [5], an MZM operating at the opposite slopes of the transfer functions for two different wavelengths [6], and parallel operation of a pair of MZMs or polarization modulators (PolMs) [7]- [9]. The major disadvantage of the approach by low biasing an MZM [5] is that the second-order harmonic distortions and the second-order intermodulation distortion (IMD2) will be generated because of the increased nonlinearity when low biasing the MZM.…”