Concurrent subbands mode for multichannel SAR imaging

Unambiguous wide swath and high azimuth resolution pose contradicting requirements on the design of SAR systems. The requirements can be overcome by using concurrent subbands technology. This paper reviews the concurrent subbands technology for the imaging of wide swath with high range-azimuth resolutions. In the designed system, the concurrent subbands technology is used to integrate a wider range signal bandwidth, and thus achieve a higher range resolution; multichannel allows a lower Pulse Repetition Frequency (PRF) and enables unambiguous wide swath. The synthetic bandwidth method is used to obtain a wide-bandwidth signal, which is described in detail. With the application of the classical Displaced Phase Centre (DPC) technique, more spatial sampling along the synthetic aperture can be used and thus reduce the PRF.