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Robust SAR Waveform Design for Extended Target in Spectrally Dense Environments
Rui Zhang1, Fuwei Wu1, Bing Gao1
1Nanjing Research Institute of Electronics Technology, Nanjing 210039, China.
Sensors (Basel, Switzerland)
|June 27, 2025
Summary
This study introduces a robust waveform design for Synthetic Aperture Radar (SAR) to improve extended target signatures in cluttered environments. The method optimizes signal-to-clutter ratio (SCR) under uncertainty, enhancing SAR imaging performance.
Area of Science:
- Electrical Engineering
- Signal Processing
- Remote Sensing
Background:
- Synthetic Aperture Radar (SAR) imaging requires robust methods for detecting extended targets, especially in spectrally dense environments.
- Existing waveform design techniques may not adequately address uncertainties in target and background scattering characteristics.
Purpose of the Study:
- To develop a robust waveform design method for enhancing extended target signatures in SAR images.
- To maximize the worst-case signal-to-clutter ratio (SCR) under statistical uncertainties.
Main Methods:
- Formulated the problem as maximizing worst-case SCR over uncertainty sets for target and background statistics.
- Derived closed-form solutions for uncertain statistics.
- Transformed the problem into a nonconvex fractional quadratically constrained quadratic problem (QCQP).
- Utilized Dinkelbach's algorithm and Lagrange duality to solve the QCQP via semidefinite programming.
Main Results:
- Developed a robust waveform design scheme for SAR imaging.
- Demonstrated the ability to handle uncertainties in scattering characteristics.
- Achieved a sufficient condition for global convergence of the proposed algorithm.
Conclusions:
- The proposed robust waveform design method effectively enhances extended target signatures in SAR images.
- The method provides a significant improvement in signal-to-clutter ratio (SCR) under uncertain conditions.
- The approach is validated through numerical examples, showing its practical applicability.
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