SAR Image Compression Using Wavelet Packets

A SAR (Synthetic Aperture Radar) system usually collects huge amount of data, and focusing of the raw data acquires complex range varying phase compensation techniques, which are generally performed off-board. The large amounts of data generated have to be stored on-board or be transmitted to a ground station via a dedicated data link. Therefore, some form of compression on the raw data provides an attractive option for SAR systems. In this paper we investigate the usage of WPT (Wavelet Packet Transform), which performs uniform division of frequency spectrum, independently on real and imaginary parts of the complex SAR raw data along with scalar quantization for compressing SAR raw data. We propose another image coding algorithm which uses rate distortion optimized WPT.