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Down-conversion and frequency spectrum convolution of the broadband signal based on active mode-locking technology
Applied Optics
|April 3, 2024
Summary
A new active mode-locking optoelectronic oscillator (OEO) enables multifunction processing for broadband signals. This processor achieves central frequency down-conversion and spectrum convolution, enhancing bandwidth by 50 times for potential radar applications.
Area of Science:
- Optoelectronics
- Signal Processing
Background:
- Broadband signals require advanced processing techniques.
- Optoelectronic oscillators (OEOs) offer unique capabilities for signal manipulation.
Purpose of the Study:
- To propose and demonstrate a multifunction processor for broadband signals using an active mode-locking optoelectronic oscillator (OEO).
- To achieve central frequency down-conversion and frequency spectrum convolution of target broadband signals (TBS).
Main Methods:
- Utilizing an active mode-locking OEO.
- Employing an optical tunable delay line (OTDL) for frequency down-conversion.
- Injecting a lower frequency signal to achieve spectrum convolution.
- Implementing harmonic mode-locking for increased convolution repetition.
Main Results:
- Demonstrated central frequency down-conversion and spectrum convolution of broadband signals.
- Achieved an equivalent bandwidth enlargement of approximately 50 times.
- Showcased flexibility in central frequency conversion and bandwidth compatibility.
Conclusions:
- The proposed active mode-locking OEO serves as a versatile multifunction processor.
- The system demonstrates significant bandwidth enhancement and processing flexibility.
- Potential applications exist in multifunctional integrated radar systems.
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