A frequency scaling (FS) imaging algorithm is proposed for spotlight bistatic SAR data processing. Range cell migration correction (RCMC) is realized through phase multiplication. The proposed algorithm is insensitive to the length of the baseline due to the high precision of the point target (PT) spectrum that we are based on. It is capable of handling bistatic SAR data with a large baseline to range ratio. The algorithms suitable for small and high squint angles are both discussed according to whether the range dependence of the second range compression (SRC) can be neglected or not. Simulated experiments validate the effectiveness of the proposed algorithm.
A new analytical imaging algorithm based on Chirp-z transform (CZT) for focusing non-parallel bistatic SAR data is proposed. The reference function multiplication (RFM) is firstly performed to finish the bulk focusing. Then the phase terms of spectrum are decomposed into range phase term and azimuth phase term, and their space-variances are eliminated by CZT independently to finish the differential focusing. The algorithm can be applied to wide scene imaging, and its effectiveness is verified by simulations.
Focusing of Spotlight Tandem-Configuration Bistatic Data with Frequency Scaling Algorithm