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Distortion compensation in continuous-time photonic time-stretched ADC based on redundancy detection
Applied Optics
|March 10, 2021
Summary
This study introduces a novel compensation scheme for photonic time-stretched analog-to-digital conversion (PTS-ADC). It effectively eliminates signal distortion in PTS-ADC systems by employing redundant detection with complementary wavelength-division multiplexers (WDMs).
Area of Science:
- Photonics
- Electrical Engineering
- Signal Processing
Background:
- Continuous-time photonic time-stretched analog-to-digital conversion (PTS-ADC) utilizes wavelength-division multiplexers (WDMs) for signal segment separation.
- Non-ideal WDM spectrum shapes lead to signal distortion during reconstruction due to inter-channel and inter-pulse mismatches.
Purpose of the Study:
- To propose and validate a signal distortion compensation scheme for continuous-time PTS-ADC.
- To eliminate signal distortion caused by inter-channel and inter-pulse mismatches in PTS-ADC.
Main Methods:
- Employed two WDMs with complementary spectrum division for redundant detection of signal segments.
- Adjusted the dispersion of the first dispersive medium to ensure partial overlap of stretched chirped pulses.
- Analyzed effective bandwidth and derived the maximum system stretch factor.
Main Results:
- The proposed scheme completely avoids distortion from inter-channel mismatch by redundant detection.
- Signal distortion induced by inter-pulse mismatch is perfectly removed through redundant modulation.
- Experimental validation confirms the effectiveness of the compensation scheme.
Conclusions:
- The redundancy detection scheme effectively compensates for signal distortion in continuous-time PTS-ADC.
- The findings provide guidelines for designing high-performance continuous-time PTS-ADC systems.
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