Complex image reconstruction and synthetic aperture laser imaging for moving targets based on direct-detection...

Area of Science:

• Optics and Photonics
• Remote Sensing
• Signal Processing

Background:

• Synthetic aperture ladar (SAL) principles enable high-resolution imaging with relative target-ladar motion.
• Existing SAL systems offer large fields of view and easy implementation but face challenges with complex image reconstruction for moving targets.

Purpose of the Study:

• To propose a novel complex image reconstruction and synthetic aperture laser imaging method for moving targets.
• To verify the effectiveness of the proposed method in both far-field simulations and near-field experiments.

Main Methods:

• Utilized a spatial light modulator and a direct-detection detector array for imaging.
• Developed a complex image reconstruction algorithm to process ladar signals.
• Conducted simulations and experiments on stop-and-go and continuously moving targets.

Main Results:

• The complex image reconstruction method was verified to achieve equivalent coherent detection, capturing phase information relative to laser wavelength.
• Successfully generated high-resolution images of moving targets under both far-field and near-field conditions.
• Demonstrated the applicability of multi-frame reconstructed complex images for SAL imaging.

Conclusions:

• The proposed SAL imaging method effectively reconstructs complex images, providing crucial phase information for moving targets.
• This technique enables high-resolution imaging of moving targets, overcoming limitations of traditional methods.
• The study validates the method's performance across various target motions and field conditions.