Implementation of the photonic time-stretch concept using an incoherent pulsed light source

Area of Science:

• Optics and Photonics
• Signal Processing
• Electromagnetics

Background:

• Conventional photonic time stretching often relies on coherent light sources.
• Achieving high performance in time stretching typically requires complex configurations.
• Incoherent light sources offer potential advantages in cost and simplicity.

Purpose of the Study:

• To introduce and demonstrate a novel technique for photonic time stretching of radio-frequency (RF) signals.
• To utilize a time-gated incoherent light source for signal processing.
• To compare the performance of this new method with conventional coherent systems.

Main Methods:

• Employing a time-gated (pulsed) incoherent light source for photonic time stretching.
• Experimentally demonstrating temporal magnification and compression of high-speed RF signals.
• Utilizing a broadband incoherent light source with a temporal gate duration significantly longer than transform-limited pulses.

Main Results:

• Achieved photonic time stretching with performance specifications (stretch factor, temporal aperture, resolution) comparable to coherent systems.
• Demonstrated time-stretch factors ranging from 0.65 to 8.66.
• Obtained a resolution of ~67.5 ps over a temporal aperture of ~23 ns, yielding a time-bandwidth product exceeding 340.

Conclusions:

• The proposed technique effectively realizes photonic time stretching using a pulsed incoherent light source.
• This method offers a viable alternative to coherent systems, providing similar performance with potentially simpler implementation.
• The demonstrated results highlight the potential of incoherent light sources in advanced RF signal processing.