【作者】 翟杰夫；

【导师】 王贞松；

【作者基本信息】 中国科学院研究生院（计算技术研究所） ， 计算机系统结构， 2004， 硕士

【摘要】 合成孔径雷达(SAR)产生大量的数据需要由卫星线路下载到地面来进行分析，处理与存储。数据量的巨大与通信线路容量的限制使得数据压缩成为一项必然的选择。早期的压缩技术由于硬件条件的限制，一般都是对原始数据进行压缩。原始数据的随机性强，冗余较少，压缩比不能达到很高。近年来由于硬件水平的发展，SAR图像数据压缩逐渐为人们所关注，并成为研究的热点问题。由于SAR图像具有较高的相关性，被认为能达到更好的压缩，有助于进一步减小对通信带宽和存储系统的要求，是合成孔径雷达系统的关键技术之一。开展SAR图像压缩技术的研究，对合成孔径雷达系统，尤其是星载合成孔径雷达系统的数据传输和存储具有重大的现实意义。本文首先对SAR图像压缩的需求和背景作了介绍，阐述了本文研究的主要目的和内容。然后回顾了压缩的一般技术，并重点对后面我们提出的图像压缩算法中用到的压缩技术进行了讨论。第三章我们讨论了SAR图像的相关性分析，尤其对噪声进行了分析和讨论。接下来第四章我们针对SAR复数图像的特点提出了两种相应的压缩算法。第五章我们讨论了基于小波的图像压缩技术，并针对SAR模值图像提出了一种低比特率下的压缩方法。更多还原

【Abstract】 SAR (Synthesis Aperture Radar) generates large amounts of data which should be transmitted to ground to do further analysis, processing. The data would easily exhaust the available capacity of downlink or storage system, so there are special interests in SAR image compression. Because of limitation of hardware at early time, people only compressed raw data which exhibits little correlation. Consequently limited compression ratio could be obtained. For the progress of hardware in recent years, people begin to focus on SAR image compression. SAR images are expected to have higher compression ratio than raw data because of higher correlation in SAR images. SAR image compression is a key technique in SAR system which can help to reduce the requirement of downlink capacity as well as storage. Research work on SAR image compression plays an important role in the design of SAR system, especially space-borne SAR system. In this thesis, we firstly introduce the background of SAR image compression and the aim of this research work. Then we discuss general compression techniques, especially those that are used in our proposed algorithms. In chapter 3 we discuss the correlation in SAR images and the model of speckle. In chapter 4, two algorithms are proposed for complex SAR image compression both making use of the characteristics of SAR images. In chapter 5, we discuss modern wavelet-based image compression algorithms and propose a wavelet-based SAR image compression algorithm working under low bit-rate.更多还原