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Recombination Dynamics in Thin-film Photovoltaic Materials via Time-resolved Microwave Conductivity
Published on: March 6, 2017
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Time-bandwidth compression of microwave signals.
Optics Express
|February 7, 2018
Summary
We developed a reconfigurable photonic system to compress the time-bandwidth product (TBP) of microwave signals. This method enhances microwave signal processing, sampling, and storage capabilities.
Area of Science:
- Photonics
- Signal Processing
- Applied Physics
Background:
- Microwave signal processing requires efficient methods for handling high-speed signals.
- Existing techniques for time-bandwidth product (TBP) compression face limitations in flexibility and dispersion levels.
- Nanosecond-long microwave signals demand specialized processing capabilities, particularly high nonlinear dispersion.
Purpose of the Study:
- To demonstrate a reconfigurable photonic anamorphic stretch transform for TBP compression.
- To achieve ultra-high nonlinear dispersion for processing nanosecond-long microwave signals.
- To enable efficient sampling, digitization, and storage of high-speed microwave signals.
Main Methods:
- Utilizing a time-spectrum convolution system to generate ultra-high nonlinear dispersion (ns/GHz).
- Employing a programmable WaveShaper to engineer the system's group delay.
- Implementing a photonic anamorphic stretch transform for signal processing.
Main Results:
- Achieved a 1.9 times compression of the TBP for a double pulse microwave signal.
- Demonstrated the reconfigurability of the photonic system through WaveShaper programming.
- Validated the capability of the system to handle nanosecond-long microwave signals.
Conclusions:
- The proposed reconfigurable photonic scheme offers an efficient method for TBP compression.
- This technology opens new avenues for generating critical microwave signal processing modules.
- The system provides enhanced capabilities for sampling, digitizing, and storing high-speed microwave signals.
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