本文提出一种采用相位调制的光电振荡器(Opto-Electronic Oscillator, OEO),通过微波双工器耦合一路微波辅助调制信号,和OEO的振荡信号一起注入到相位调制器中,提高辅助调制信号的功率可展宽光谱并大幅降低光载波功率,从而降低因光纤非...本文提出一种采用相位调制的光电振荡器(Opto-Electronic Oscillator, OEO),通过微波双工器耦合一路微波辅助调制信号,和OEO的振荡信号一起注入到相位调制器中,提高辅助调制信号的功率可展宽光谱并大幅降低光载波功率,从而降低因光纤非线性导致的光链路散射噪声,实现OEO低相噪输出。搭建了实验测试系统,辅助调制信号采用1.4 GHz~1.9 GHz的线性调频信号,调制系数为2.4,与不加辅助调制相比,OEO输出信号在10 kHz频偏处的相位噪声优化了32.4 dB。In this paper, a phase-modulated opto-electronic oscillator (OEO) is proposed, which uses phase modulation for spectra broadening to suppress the fiber optical link noise caused by long fiber transmission. A microwave-assisted modulation signal can be coupled by a microwave diplexer and injected into the phase modulator together with the oscillating signal of the OEO. The spectra can be greatly broadened by the strong assisted modulation signal, thus reducing the scattering noise caused by the nonlinearity of the optical fiber. Experimental tests were conducted, a linear frequency modulation signal ranging from 1.4 GHz to 1.9 GHz with a modulation coefficient of approximately 2.4 was used as the assisted modulation signal. Compared with no assisted modulation, the phase noise of the oscillating signal at a frequency offset of 10 kHz was optimized by 32.4 dB.展开更多
文摘本文提出一种采用相位调制的光电振荡器(Opto-Electronic Oscillator, OEO),通过微波双工器耦合一路微波辅助调制信号,和OEO的振荡信号一起注入到相位调制器中,提高辅助调制信号的功率可展宽光谱并大幅降低光载波功率,从而降低因光纤非线性导致的光链路散射噪声,实现OEO低相噪输出。搭建了实验测试系统,辅助调制信号采用1.4 GHz~1.9 GHz的线性调频信号,调制系数为2.4,与不加辅助调制相比,OEO输出信号在10 kHz频偏处的相位噪声优化了32.4 dB。In this paper, a phase-modulated opto-electronic oscillator (OEO) is proposed, which uses phase modulation for spectra broadening to suppress the fiber optical link noise caused by long fiber transmission. A microwave-assisted modulation signal can be coupled by a microwave diplexer and injected into the phase modulator together with the oscillating signal of the OEO. The spectra can be greatly broadened by the strong assisted modulation signal, thus reducing the scattering noise caused by the nonlinearity of the optical fiber. Experimental tests were conducted, a linear frequency modulation signal ranging from 1.4 GHz to 1.9 GHz with a modulation coefficient of approximately 2.4 was used as the assisted modulation signal. Compared with no assisted modulation, the phase noise of the oscillating signal at a frequency offset of 10 kHz was optimized by 32.4 dB.