Zhao Quanjing, Yan Juanjuan
Appl Opt. 2021 Jul 20;60(21):5995-6001. doi: 10.1364/AO.426888.
A scheme for binary phase-coded microwave signal generation is proposed and experimentally demonstrated with a dual-parallel Mach-Zehnder modulator (DPMZM). The carrier of the generated phase-coded signal is provided by the built-in dual-loop optoelectronic oscillator (OEO) based on the DPMZM. The principle of this signal generator and the oscillating condition of the OEO is theoretically described in detail. It is found that phase-coded signals can be produced by setting the three working points and the modulation depth of the DPMZM. In the proving experiment, a 10-GHz oscillating signal with a side mode suppression ratio of 49 dB is generated. The phase noise of this carrier wave is measured to be -80/ at 10 kHz offset with a 100-m and 1-km optical fiber used in the two oscillation loops. When 1-Gbit/s and 2-Gbit/s coding signals are, respectively, applied to the DPMZM, two 10-GHz self-oscillating phase-coded signals are eventually produced, and the phase shift in the signals is successfully confirmed with the phase information extracted from the phase-coded signals.
提出了一种用于二进制相位编码微波信号生成的方案，并使用双并行马赫-曾德尔调制器（DPMZM）进行了实验验证。所生成的相位编码信号的载波由基于DPMZM的内置双环光电振荡器（OEO）提供。从理论上详细描述了该信号发生器的原理以及OEO的振荡条件。发现通过设置DPMZM的三个工作点和调制深度可以产生相位编码信号。在验证实验中，生成了边模抑制比为49 dB的10 GHz振荡信号。在两个振荡环路中分别使用100 m和1 km的光纤时，测得该载波在10 kHz偏移处的相位噪声为-80 dBc/Hz。当分别将1 Gbit/s和2 Gbit/s的编码信号施加到DPMZM时，最终产生了两个10 GHz的自振荡相位编码信号，并且通过从相位编码信号中提取的相位信息成功确认了信号中的相位偏移。
