| 摘要: |
| 方位多通道体制是当前合成孔径雷达（SAR）系统主流的高分宽幅实现方式。而将方位多通道技术与斜视波束扫描（聚束、滑动聚束、TOPS）工作模式相结合可以实现灵活的更高分辨率或者更宽幅宽的遥感观测。然而由于斜视以及波束扫描会使得回波信号的多普勒带宽远大于通道数与脉冲重复频率（PRF）的乘积，使得传统的多通道成像方法失效。为了解决上述问题，本文提出一种基于方位去斜加方位重采样的多模式斜视多通道SAR成像方法，该方法通过对各个通道信号分别进行方位去斜以及对去斜、线性距离走动校正（LRWC）后的信号进行方位重采样来来解决方位时变的问题，使得传统的多通道成像方法可以使用。理论分析与实验结果均验证了该方法可以处理多模式的斜视多通道SAR数据，并且得到聚焦良好的图像。 |
| 关键词: 合成孔径雷达(SAR) 方位多通道 斜视 波束扫描 |
| DOI： |
| 分类号:TN957.52 |
| 基金项目:国家重点研发计划“星载新体制SAR综合环境监测技术”(2017YFB0502702) |
|
| Squinted Multichannel SAR Imaging with Several Modes |
|
|
|
|
| Abstract: |
| Azimuth multichannel system is the mainstream implementation method of high-resolution and wide-swath in synthetic aperture radar (SAR) systems. The combination of azimuth multi-channel system and squint beam steering (spotlight, sliding spotlight, TOPS) can realize flexible remote sensing observation with higher resolution or wider swath width. However, due to the existence of squint angle and beam steering, the Doppler bandwidth of the echo is much larger than the product of the number of channels and pulse repetition frequency (PRF), which makes the traditional multi-channel imaging methods ineffective. To solve the above problems, a multi-mode large squint multi-channel SAR imaging method based on azimuth Dechirp and azimuth resampling is proposed in this paper. This method solves the problem of azimuth time variation by Dechirp processing the signals of each channel and azimuth resampling processing the signals after Dechirp and linear range walk correction (LRWC), so that the traditional multi-channel imaging method can be used. Theoretical analysis and experimental results show that this method can process multi-mode large squint multi-channel SAR data and obtain well-focused images. |
| Key words: Synthetic aperture radar (SAR) azimuth multi-channel squint beam steering |