A novel electro-optic sampling system by using delay-time tunable pulsed laser sources

Opto-mechanic delay line (OMDL) is the key component to achieve the temporal scanning of optical pulse train in conventional electro-optic sampling (EOS) systems. In this work, we briefly demonstrate a modified EOS technique for characterizing the free-running microwave signals by using an optoelectronic phase shifter (OEPS) as a novel delay-time controller. The OEPS is designed to integrate with the optical source for linearly and continuously controlling the delay-time of optical pulse-train, which essentially overcomes the drawbacks in current EOS systems using the OMDL. The performance of the novel EOS system as well as its key parameters such as maximum scanning period, the sampling resolution, the sampling linearity are characterized.