Self-calibrated frequency response measurement of photodetectors based on photonic sampling

A simple and novel method is proposed for the self-calibrated measurement of high-speed photodetectors (PDs) based on photonic sampling by using a mode-locked laser (MLL). Through the photonic sampling measurements, the uneven response of the MLL can be determined. The prominent advantage of the proposed method lies that the self-reference extraction of the frequency response of the PD can be achieve without the need of any extra electrical/optical transducer standard. In the experiment, a commercial PD is measured by using a MLL with the repetition frequency of 21.936 MHz. The measurement results fit in with the conventional electro-optic frequency sweep measurement.