Residual Motion Error Correction with Backprojection Multisquint Algorithm for Airborne Synthetic Aperture Radar...

Area of Science:

• Geodesy and Remote Sensing
• Geophysical Imaging

Background:

• Precise motion compensation is critical for high-quality digital elevation models (DEMs) in airborne interferometric synthetic aperture radar (InSAR) data processing.
• Existing methods may not fully address residual motion errors (RME) impacting InSAR data accuracy.

Purpose of the Study:

• To develop a novel InSAR motion compensation method combining backprojection (BP) and multisquint (MSQ) techniques.
• To improve the accuracy of DEM generation from airborne InSAR data.

Main Methods:

• The proposed backprojection multisquint (BP-MSQ) algorithm integrates BP for SAR image focusing using navigation data.
• It derives an explicit mathematical expression for residual motion error (RME) in BP images.
• The multisquint (MSQ) algorithm is then applied in the azimuth spatial wavenumber domain for refined RME correction.

Main Results:

• The BP-MSQ algorithm simultaneously leverages the motion error correction strengths of both BP and MSQ.
• Significant improvements in InSAR image quality were observed.
• Both simulation and real data experiments validated the algorithm's effectiveness.

Conclusions:

• The developed BP-MSQ algorithm offers a superior approach to motion compensation in airborne InSAR processing.
• This method leads to enhanced DEM accuracy and overall InSAR data quality.
• The findings are crucial for advancing high-resolution topographic mapping applications.