Design of block adaptive quantization algorithm after IF sampling of space-borne SAR echoes
星载SAR回波中频采样后直接BAQ的设计

This paper presents a design of block adaptive quantization (BAQ) algorithm immediately after echoes inter-frequency (IF) sampling for space-borne SAR system. Theoretical derivation is given in detail. Compared to the typical structure which implements BAQ after digital down conversion (DDC) in orbit, electrical system design is simplified and less hardware resource is needed when performing DDC on ground. Experimental results show that the two methods achieve similar performance with the same data rate when using mixer-free structure, and the resource for the new design is less than 1/3 of the resource for the typical structure.