Image Combination Analysis in SPECAN Algorithm of Spaceborne SAR

An analysis of image combination in SPECAN algorithm is delivered in time frequency domain in detail and a new image combination method is proposed. For four multi looks processing one sub aperture data in every three sub apertures is processed in this combination method. The continual sub aperture processing in SPECAN algorithm is realized and the processing efficiency can be dramatically increased. A new parameter is also put forward to measure the processing efficient of SAR image processing. Finally, the raw data of RADARSAT are used to test the method and the result proves that this method is feasible to be used in SPECAN algorithm of spaceborne SAR and can improve processing efficiently. SPECAN algorithm with this method can be used in quick look imaging.