A Polyphase Filter Bank Interpretation of Coherent Image Formation
نویسنده
چکیده
Coherent image formation in step transform algorithm is realized by overlapped subapertures in both range and cross range direction. Subaperture formation principle is treated as multiplication of target backscatter signature with a set of overlapped and shifted complex, conjugate reference functions and subsequent spectral analysis. A polyphase filter bank interpretation of step transform is presented here from Joint Time (space) Frequency (JTF) analysis viewpoint. Real time image formation is facilitated by such interpretation. Simulation results from such analysis are provided in the paper.
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