High Resolution, Wide Swath SAR using Sub-aperture Sub-band Technique

The most important specifications of spaceborne synthetic aperture radar (SAR) are spatial resolution and swath width. But in conventional SAR, there is a well known trade-off between them because of the pulse mode. A method named multiple azimuth beam (MAB) with single transmitter is proposed to solve these difficulties in previous articles. By this method the swath is about N (beam number) times wider than that of the equivalent conventional SAR, or the azimuth resolution can be improved by a factor of approximately N. Meanwhile, stepped-frequency waveform is often used to obtain large effective bandwidth for high range resolution by transmitting the pulses with sequentially changing carrier frequency. In this paper, a method named sub-aperture sub-band technique is adopted to achieve wide swath and two-dimension high resolution simultaneously