上海交通大学智能微波光波融合创新中心（imLic）硕士生化世玉同学的工作— Equivalence of photonic sampling to signal holding in channel-interleaved photonic ADCs by controlling photo-detection response的相关研究成果近期被Optics Express杂志接收。该工作得到了国家重点研发计划、国家自然科学基金、上海市青年科技英才杨帆计划等的资助。该研究团队利用首次分析了光子模数转换系统中光子采样后的信号保持过程，并通过控制光电转换的频率响应实现了等效信号保持作用，与传统的矩形频率响应相比，该频率响应通过产生信号保持作用有效地抑制了光采样与电量化之间的时间失配，从而提升大规模光子模数转换系统的性能，理论分析表明该方法不受限于通道数，能够为未来实现高采样率的光子模数转换系统提供可靠的理论支撑。
摘要:Substantial interests have been attracted in the use of photonic sampling and electronic digitizing for photonic analog-to-digital converter (PADC). However, the nature of that photo-detection with signal holding effects has not been well established. This paper analyzes the equivalence of photonic sampling to signal holding by controlling photo-detection response. In the frequency domain, the high-frequency components generated by the sampling pulse train are folded back into the Nyquist band resulting the signal holding response when the output is digitized. We proposed an approximate response of the photodetector (PD) to verify the theoretical analysis. It is found that the photonic sampling serves as the conventional switch-based sample-and-hold (S&H) circuit in channel-interleaved photonic analog-to-digital converter. In the experiment, the signal holding directly inhibits the timing mismatch without sophisticated calibrations.