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Photonics-assisted compressed sensing radar receiver for frequency domain non-sparse signal sampling based on
Optics Letters
|February 1, 2023
Summary
This study introduces a photonics-assisted radar receiver using compressed sensing (CS) to capture non-sparse signals. The novel system effectively reconstructs undersampled radar echoes, enabling accurate target ranging with minimal error.
Area of Science:
- Photonics
- Radar Systems
- Signal Processing
Background:
- Traditional radar receivers struggle with frequency domain non-sparse signals.
- Compressed sensing (CS) offers potential for efficient signal acquisition.
- Photonics integration can enhance radar receiver capabilities.
Purpose of the Study:
- To propose and validate a photonics-assisted radar receiver employing compressed sensing (CS).
- To demonstrate the system's ability to receive and reconstruct frequency domain non-sparse radar signals.
- To evaluate the ranging accuracy of the proposed system.
Main Methods:
- Utilizing a photonic random demodulator (RD) with a laser diode (LD), dual-drive Mach-Zehnder modulator (DD-MZM), and photodetector (PD).
- Mixing radar echo signals with a pseudo-random binary sequence (PRBS).
- Undersampling the mixed signal with an analog-to-digital converter (ADC) and reconstructing using dictionary learning and sparse algorithms.
Main Results:
- Successful reconstruction of various undersampled non-sparse radar echo signals.
- Achieved ranging errors within 5 cm at a compression ratio of 20.
- Demonstrated the feasibility of photonics-assisted CS for radar signal recovery.
Conclusions:
- The proposed photonics-assisted CS radar receiver effectively reconstructs undersampled non-sparse signals.
- This technology offers a promising solution for advanced radar signal processing.
- The system achieves high ranging accuracy, crucial for target detection.
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