激光与光电子学进展, 2020, 57(17): 170603, 网络出版: 2020-09-01
Reconfigurable Triangular and Square Waveforms Generation Using Optical Polarization Division Modulation
1空军工程大学信息与导航学院, 陕西 西安 710077
2中国空间技术研究院西安分院, 陕西 西安 710077
光通信 微波光子 三角波 方波 偏振复用调制器 optical communications microwave photonic triangular waveform square waveform polarization division multiplexing modulator
提出了基于偏振复用双平行马赫-曾德尔调制器(PDM-DPMZM)的基频/倍频三角波和方波产生方案。DPMZM1加载驱动射频信号,DPMZM2不加载驱动射频信号仅进行光载波相移时,检偏拍频后可产生载波基频的三角波和方波信号;当DPMZM1和DPMZM2同时加载驱动射频信号,且相位差控制为90°时,两路偏振光独立拍频后,可以产生载波二倍频的三角波和方波信号。通过改变射频信号的相位差和连接方式,仿真中分别产生了重复频率为10 GHz和20 GHz的三角波方波信号,通过射频信号幅度偏移和直流偏置漂移验证了方案的稳定性。所提方案采用了单调制器,且无需光电滤波处理,具有产生信号格式可重构、信号参数可调谐的优势,可满足未来高频电子系统的应用需求。
Optical generator to triangular and square waveforms with fundamental frequency and double frequency is proposed by using a polarization division multiplexing dual-parallel Mach-Zehnder modulator (PDM-DPMZM). With this approach, as the DPMZM1 is driven by an RF signal, and DPMZM2 only performs optical carrier phase shift by direct current (DC) bias without RF signal driven, triangular and square waveforms with fundamental frequency can be obtained following a polarizer and photodetector; as the two DPMZMs are both driven by an RF signal with a 90° phase difference, two waveforms with double frequency can also be generated. The proposed approach was verified by simulation. Triangular and square waveforms with repetition rates of 10 GHz and 20 GHz were generated by changing the phase difference and connection mode of the RF signal. The proposed structure features a single modulator and is filter-free, and demonstrates good tunability and large reconfigurability, which has potential applications in future high-frequency electronic systems.