A Real-time Data Compression Algorithm for SAR Complex Images Based on Block Adaptive Quantization
Xia Wei-ping, Zhensong Wang, Han Jizhong · 2006
With the development of high resolution synthetic aperture radar(SAR),great quantity of complex data are generated by the real-time SAR image processor which makes effective complex image compression algorithm necessary to release the burden of the capacity of the downlink and the storage system.Complex image compression can reduce the data amount.However the compression algorithm for the SAR complex images is special,which needs to keep the phase preserved.Generally speaking,the optical image compression algorithm isn't suitable for SAR complex images.The coherent speckle noise and the random phase of SAR complex images make compression difficult.By examining the characteristic of complex image data,this paper presents an efficient compression method based on block adaptive quantization(BAQ) after removal of frequency redundancy.The BAQ is adapted to the high dynamic range of SAR complex images and reduces the quantization error.The calibrations of SAR image such as resolution in azimuth and range,integrated side lobe ratio and peek to side lobe ratio,interference images etc.indicate that our method is effective for the fidelity of SAR images' magnitude and phase under the compression ratio of 16∶1.What is more,it has the preference of low complexity and easy implementation in real-time system.