低相噪光子式微波接收机的研制

Design and fabrication of low phase noise photonic microwave receiver

首次对微波接收机的相噪进行了理论建模,并提出了一种基于光子技术的新型微波接收机,该接收机采用微波光子链路来代替电缆,使用光电振荡器代替电子振荡器来作为本振源,并基于上述理论模型分析了该种接收机较传统电子式接收机在相噪指标上的优越性。让10GHz载波信号分别通过电、光两种接收机,对比输出信号的相噪情况,实验结果表明:通过传统电子接收机接收后,载波信号相噪在1kHz频偏增加了30dB;而对于本文所提新型光子式接收机,载波信号相噪在1kHz频偏仅增加10dB,说明了该种新型接收机在集成了微波光子链路与光电振荡器两种新型光子技术后,相噪指标得到了显著提高。

The phase noise of microwave receiver is modeled theoretically,and a novel microwave receiver based on optics technology is proposed in this paper.Microwave photonic link and opto-electronic oscillator,replacing cable and electronic oscillator respectively,are integrated in this new receiver to achieve low phase noise.Based on the above theoretical model,the superiority of this kind of receiver over the traditional electronic receiver in phase noise index is analyzed.Let the 10 GHz carrier signal pass through both kinds of the electric and optics receivers respectively,and the measured phase noise data of output signal are compared and analyzed.The experimental results show that the phase noise of the carrier signal is increased by 30 dB at 1 kHz frequency offset after receiving by the traditional electric receiver,but it is only 10 dB for the new optics receiver proposed in this paper.It is shown that the phase noise index is significantly improved after both microwave photonic link and opto-electronic oscillator being integrated in microwave receiver.