Scattering Centers Parameter Estimation Accuracy and Resolution Improvement Limit Derivation of Multiband Fusion Technology

Multiband fusion (MBF) technology has the ability to achieve a high inverse synthetic aperture radar (ISAR) range resolution without a hardware upgrade. In this technology, several sub-band echoes (SBE) corresponding to different bandwidth and different center frequenmcy are fused to produce wideband echoes (WBE). Therefore, the resolution of the SBE is improved. In state of art MBF methods, the SBE are assumed to obey a scattering model and the scattering center parameters (SCP) in the model are estimated to reconstruct the WBE. However, there is a lack of derivation of the accuracy of SCP and the limit of resolution improvement under the geometric theory of diffraction (GTD) model. The Cramer-Rao lower bound (CRLB) is used to achieve the deravation in this paper.