Simultaneous even- and third-order distortion suppression in a microwave photonic link based on orthogonal polarization modulation, balanced detection, and optical sideband filtering.
Simultaneous even- and third-order distortion suppression in a microwave photonic link based on orthogonal polarization modulation, balanced detection, and optical sideband filtering.
复制标题
DOI：
10.1364/oe.24.014812
复制
发表时间：
2016-06
期刊：
影响因子：
3.8
通讯作者：
Xiuyou Han;Xiang Chen;J. Yao
中科院分区：
文献类型：
--
作者：
Xiuyou Han;Xiang Chen;J. Yao
提出了一种利用偏振调制器（PolM）、光学带通滤波器（OBPF）和平衡光电探测器（BPD）同时抑制偶阶和三阶失真的微波光子链路（MPL），并进行了实验验证。通过采用基于PolM的正交偏振调制和基于BPD的平衡差分检测，抑制了偶阶失真。三阶失真（IMD 3）通过优化OBPF的光谱响应，并在光载波和PolM相位调制信号的边带之间具有最佳功率比来抑制。由于IMD 3的抑制是在MPL针对偶数阶失真抑制进行优化时实现的，因此所提出的MPL可以在同时抑制偶数阶和三阶失真的情况下操作。对所提出的MPL进行了理论分析和实验验证。对于f1 = 10 GHz和f2 = 19.95 GHz的双音RF信号，与传统MPL相比，无杂散动态范围（SFDR 2）对于二次谐波（2f 1）增强了23.4 dB，对于二次互调（f2-f1和f1 + f2）增强了29.1和27.6 dB。对于f1 = 9.95 GHz和f2 = 10 GHz的双音RF信号，与传统MPL相比，SFDR 3增加了13.1 dB。
A microwave photonic link (MPL) with simultaneous suppression of the even-order and third-order distortions using a polarization modulator (PolM), an optical bandpass filter (OBPF), and a balanced photodetector (BPD) is proposed and experimentally demonstrated. The even-order distortions are suppressed by utilizing orthogonal polarization modulation based on the PolM and balanced differential detection based on the BPD. The third-order distortions (IMD3) are suppressed by optimizing the spectral response of the OBPF with an optimal power ratio between the optical carrier and the sidebands of the phase-modulated signals from the PolM. Since the suppression of the IMD3 is achieved when the MPL is optimized for even-order distortion suppression, the proposed MPL can operate with simultaneous suppression of the even-order and third-order distortions. The proposed MPL is analyzed theoretically and is verified by an experiment. For a two-tone RF signal of f1 = 10 GHz and f2 = 19.95 GHz, the spurious-free dynamic range (SFDR2) is enhanced by 23.4 dB for the second harmonic (2f1), and 29.1 and 27.6 dB for the second intermodulation (f2-f1 and f1 + f2), as compared with a conventional MPL. For a two-tone RF signal of f1 = 9.95 GHz and f2 = 10 GHz, the SFDR3 is increased by 13.1 dB as compared with a conventional MPL.