Zhang Man, Meng Zhichao, Wang Guanyong, Xue Yonghong
School of Electronic and Communication Engineering, Guangzhou University, Guangzhou 510006, China.
Key Laboratory of On-Chip Communication and Sensor Chip, Guangdong Higher Education Institutes, Guangzhou 510006, China.
Sensors (Basel). 2024 May 21;24(11):3278. doi: 10.3390/s24113278.
High-resolution and wide-swath (HRWS) synthetic aperture radar (SAR) imaging with azimuth multi-channel always suffers from channel phase and amplitude errors. Compared with spatial-invariant error, the range-dependent channel phase error is intractable due to its spatial dependency characteristic. This paper proposes a novel parameterized channel equalization approach to reconstruct the unambiguous SAR imagery. First, a linear model is established for the range-dependent channel phase error, and the sharpness of the reconstructed Doppler spectrum is used to measure the unambiguity quality. Furthermore, the intrinsic relationship between the channel phase errors and the sharpness is revealed, which allows us to estimate the optimal parameters by maximizing the sharpness of the reconstructed Doppler spectrum. Finally, the results from real-measured data show that the suggested method performs exceptionally for ambiguity suppression in HRWS SAR imaging.
具有方位多通道的高分辨率宽测绘带（HRWS）合成孔径雷达（SAR）成像总是存在通道相位和幅度误差。与空间不变误差相比，距离相关的通道相位误差因其空间依赖性特征而难以处理。本文提出了一种新颖的参数化通道均衡方法来重建无模糊的SAR图像。首先，针对距离相关的通道相位误差建立线性模型，并使用重建多普勒频谱的锐度来衡量无模糊质量。此外，揭示了通道相位误差与锐度之间的内在关系，这使我们能够通过最大化重建多普勒频谱的锐度来估计最佳参数。最后，实测数据结果表明，所提方法在HRWS SAR成像的模糊抑制方面表现出色。
