Phase Imbalance Estimation for Azimuth Multi-Channel ScanSAR System

The new concept of combining the azimuth multichannel synthetic aperture radar (SAR) system with Scan mode was put forward to meet requirements future developments in high-resolution and ultrawide-swath SAR design. However, phase imbalance between channels is inevitable, which will greatly reduce quality image. This article proposed an approach estimation for ScanSAR system. For this, particularity target Doppler spectrum analyzed firstly. Then, theoretical derivation reveals equivalence scene ambiguity ambiguity. Subsequently, main idea determine index ambiguous component by sparse recovery method. equivalent real measured data experiment demonstrates effectiveness approach. Compared results signal subspace comparison method, method shows better performance. Finally, details implementation process algorithm are described analysis simulation experiments.