Photonic stepped-frequency radar with 150-m unambiguous detection and centimeter range resolution.

Area of Science:

• Photonics
• Radar Systems Engineering
• Optical Communications

Background:

• Photonic stepped-frequency radars offer wide bandwidth and high resolution but suffer from range ambiguity.
• Existing radar range ambiguity is inversely proportional to frequency step, limited by acousto-optic or electro-optic modulators.

Purpose of the Study:

• To overcome the range ambiguity limitation in photonic stepped-frequency radars.
• To achieve centimeter range resolution with extended unambiguous detection range.

Main Methods:

• Utilizing a fiber cavity to inject a narrowband, stepped-frequency signal.
• Implementing optical frequency-shifting modulation within the fiber cavity.

Main Results:

• Demonstrated a broadband photonic stepped-frequency radar with 150-m unambiguous detection.
• Achieved centimeter range resolution, surpassing existing photonic and electronic systems.
• Effectively resolved the trade-off between ambiguity range and shifting frequency.

Conclusions:

• The novel fiber cavity approach significantly enhances unambiguous detection range for photonic stepped-frequency radars.
• This method maintains signal quality and bandwidth, enabling practical outdoor radar applications.
• The technology represents a significant advancement over current radar systems.