Widely tunable, low phase noise microwave source based on a photonic chip

Area of Science:

• Photonics
• Microwave Engineering
• Applied Physics

Background:

• Spectrally pure microwave sources are crucial for advanced applications like wireless communication and radar.
• Existing sources often struggle with size, weight, and power consumption for in-field use.
• Optoelectronic oscillators (OEOs) offer a promising hybrid approach using optics for high-frequency signal generation.

Purpose of the Study:

• To present a widely tunable, low phase noise microwave source.
• To demonstrate a compact and integrated solution for pure microwave signal generation.
• To explore the potential of photonic integrated circuits for advanced microwave applications.

Main Methods:

• Development of a microwave source based on a photonic chip.
• Utilizing on-chip stimulated Brillouin scattering as a narrowband active filter.
• Implementing a hybrid optical and electronic cavity design (optoelectronic oscillator).

Main Results:

• Achieved single-mode OEO operation and ultrawide frequency tunability.
• Demonstrated very low close-to-carrier phase noise.
• Validated the performance of the photonic chip-based microwave source.

Conclusions:

• The presented photonic chip-based OEO enables compact, integrated, and spectrally pure microwave signal generation.
• This technology paves the way for next-generation in-field microwave applications.
• On-chip stimulated Brillouin scattering is effective for narrowband filtering in OEOs.