关键词: 星载合成孔径雷达, 中频采样, FPGA, 数字正交解调, BAQ压缩

Abstract:

We studied the scheme of space-borne synthetic aperture RADAR(SAR) data processing based on intermediate frequency sampling and the implementation method on FPGA. For a traditional space-borne SAR system, the video signal is first demodulated usually by analog method, and then sampled and compressed. This paper employs the intermediate frequency sampling technique to realize the quadrature demodulation and processing of space-borne SAR data. We analyzed the digital quadrature demodulation and the block adaptive quantization algorithms, and accomplished the FPGA design and simulation. The results show that the design scheme is feasible. Compared with the analog method, the employment of intermediate frequency sampling has improved the reliability and performance of the system, and it presents the trend of SAR data processing.

Key words: synthetic aperture RADAR(SAR), intermediate frequency sampling, field programmable gate array(FPGA), digital quadrature demodulation, block adaptive quantization(BAQ)