Millimeter-wave and microwave signal generation by low-bandwidth electro-optic phase modulation

Area of Science:

• Photonics and Optics
• Electrical Engineering
• Signal Processing

Background:

• Generating high-bandwidth electrical signals is crucial for advanced communication and measurement systems.
• Existing methods face limitations in bandwidth, time aperture, or flexibility.

Purpose of the Study:

• To propose and demonstrate a novel photonic-based technique for generating electrical signals up to 50 GHz.
• To achieve wide time apertures (nanoseconds) using low-frequency modulation.

Main Methods:

• Employing low-frequency (up to 2 GHz) electro-optic phase modulation of time-stretched optical pulses.
• Utilizing a group delay dispersion circuit as a transversal filter for phase-to-amplitude conversion.
• Leveraging the chirp of stretched optical pulses for frequency upshifting control.

Main Results:

• Numerical demonstration of generating user-defined electrical waveforms, including square waves.
• Achieved signal bandwidth approaching 50 GHz with nanosecond time apertures.
• Validated high resolution and wide-band capabilities of the proposed photonic technique.

Conclusions:

• The proposed photonic technique offers a viable method for high-bandwidth electrical waveform generation.
• The technique provides flexibility in waveform design through low-frequency modulation and dispersion control.
• This approach has potential applications in high-speed electronics and optical signal processing.