With the combination of digital beamforming (DBF) processing, multichannel synthetic aperture radar(SAR) systems in azimuth promise well in high-resolution and wide-swath imaging, whereas conventional processing methods don’t take the nonuniformity of scattering coefficient into consideration. This paper brings up a robust adaptive Multichannel SAR processing method which utilizes the Capon spatial spectrum estimator to obtain the spatial spectrum distribution over all ambiguous directions first, and then the interference-plus-noise covariance Matrix is reconstructed based on definition to acquire the Multichannel SAR processing filter. The performance of processing under nonuniform scattering coefficient is promoted by this novel method and it is robust again array errors. The experiments with real measured data demonstrate the effectiveness and robustness of the proposed method.
Time-Frequency Distribution Series (TFDS), which achieves an effective balance between the time-frequency resolution
and the cross-term interference, can effectively reconstruct complicated maneuver targets' instantaneous ISAR images.
However, original algorithm is quite inefficient, and the approach to fast computation proposed in some literature cannot
be directly applied to engineering. In this correspondence, a straightforward realizable two-dimensional filter is derived.
Meanwhile, FTFDS, as the fast implementation of TFDS, is proposed based on the formula, and computational burden of
FTFDS is analyzed theoretically and experimentally in detail. The analysis of FTFDS indicates that FTFDS makes a
great advance of efficiency. As FTFDS fits parallel process, time-frequency analysis by FTFDS can be approximately
carried out in real-time. Simulated data processing has shown that FTFDS is practical and valid in fast reconstruction of
instantaneous ISAR imaging.