Author Affiliations
Abstract
1 Information and Navigation College, Air Force Engineering University, Xi’an 710077, China
2 Key Laboratory of Radar Imaging and Microwave Photonics, Ministry of Education, Nanjing University of Aeronautics and Astronautics, Nanjing, 210016, China
An approach for photonic generation of a frequency-octupled phase-coded signal based on carrier-suppressed high-order double sideband modulation is proposed and experimentally demonstrated. The key component of the scheme is an integrated dual-polarization quadrature phase shift keying modulator, which is used to achieve the carrier-suppressed high-order double sideband modulation. At the output of the modulator, two fourth-order optical sidebands are generated with the optical carrier suppressed. After that, a Sagnac loop incorporating a fiber Bragg grating and a phase modulator is employed to separate the two optical sidebands and phase modulate one sideband with a binary coding signal. The approach features large carrier frequency tuning range for the generated phase-coded signal from several megahertz to beyond the W-band. A proof-of-concept experiment is carried out. The 2 Gbit/s phase-coded signals with frequencies of 16.48, 21.92, and 29.76 GHz are generated.
060.2330 Fiber optics communications 060.5625 Radio frequency photonics Chinese Optics Letters
2017, 15(7): 070603
空军工程大学信息与导航学院, 陕西 西安 710077
提出了一种使用光学技术产生可调谐的四倍频相位编码信号的方案。利用一个马赫-曾德尔调制器(MZM),一个光滤波器(OBPF),一个布拉格光栅(FBG),一个环形器,两个偏振调制器(PolM)和光电探测器,结合波长复用技术、偏振调制技术和平衡探测技术,产生四倍频相位编码信号。仿真结果表明,此方法产生的相位编码信号具有大调谐范围,高倍频系数。仿真产生的20 GHz和40 GHz相位编码信号分别具有10.10 dB和9.79 dB的峰值旁瓣比,压缩比都是128。同时,从相位编码中恢复出来的相位信息分别具有200°和206°的变化。仿真结果验证了产生四倍频相位编码信号的可行性,所产生的相位编码信号具有20~40 GHz的调谐范围,同时还表现出很好的脉冲压缩性能。
微波光子 相位编码 四倍频 平衡探测 偏振调制 microwave photonics phase-coded frequency quadrupling balanced detection polarization modulation
提出一种基于单光频梳的简单, 灵活和稳定的变频方法。该方法使用了双偏振正交移相器, 该调制器是一种集成调制器, 集成了两个双平行马赫-曾德尔调制器(DPMZM), 其中一个DPMZM作为光频梳产生器, 另一个进行载波抑制单边带调制产生单边带信号。从该调制器输出的信号是一个正交的耦合信号, 在偏振控制器和偏振片的控制下, 被转化为一个具有固定偏振角的信号, 最后送入光电探测器实现微波信号的产生。仿真结果表明, 通过适当调整该集成调制器中6个直流偏置点和外接的移相器, 可以实现多频段变频。比如C波段3.8 GHz的信号可以被变频到X, Ku, K和Ka波段; X波段9.6 GHz的信号可以被下变频到C波段同时也可以被上变频到Ku, K, Ka波段。除此之外, 整个系统体现出对直流偏置点漂移的良好适应性, 具有很好的可操作性。
光学器件 微波光子 载波抑制单边带调制 光频梳 多频段变频 变频性能
