Application of the multiple PRF technique to resolve Doppler centroid estimation ambiguity for spaceborne SAR

The range correlation technique for resolution of Doppler centroid estimation ambiguity for a spaceborne SAR is reviewed. A new technique using multiple pulse repetition frequencies (PRFs) is presented. An algorithm employing simple integer arithmetic for radar systems, such as moving target indicator radar (MTIR) systems, where the PRFs contain a large common divisor, is formulated. For SAR systems, where other performance factors control selection of the PRFs, an algorithm that uses PRFs of arbitrary numerical values is devised to resolve the ambiguity. The performance of this multiple PRF technique is analyzed using a statistical error model. An example is presented for the Shuttle Imaging Radar-C (SIR-C) C-band SAR