Abstract | ||
---|---|---|
This letter extends the “two-step” focusing approach to sliding spotlight (SS) synthetic aperture radar (SAR) with stepped frequency chirps, where two major points should be looked out. One is the slant-range variation among one group of subpulses introduced by the radar platform position changing. In the stripmap mode, an effective approach to compensate this variation is to multiply each subband echo with a phase ramp in the Doppler domain. Herein, we apply this approach to the SS SAR. The other is the residual Doppler bandwidth after azimuth deramping with a fixed reference function. To remove this residual bandwidth, a range-frequency-dependent reference function (FDRF) combined with azimuth zero-padding was developed in a spotlight SAR with a single subband. In this letter, we extend the FDRF to the multiple-subband SS SAR, where the FDRF also depends on the subband carrier frequency. The main contribution of this letter is that the chirp z transform is employed to acquire an identical azimuth output pixel interval for different range frequencies and different subbands. All the aforementioned processing and the bandwidth synthesis are imbedded into the “two-step” focusing approach, which is validated by simulation results. |
Year | DOI | Venue |
---|---|---|
2014 | 10.1109/LGRS.2014.2306206 | IEEE Geosci. Remote Sensing Lett. |
Keywords | Field | DocType |
subband carrier frequency,synthetic aperture radar,sliding spotlight synthetic aperture radar,multiple-subband ss sar,residual doppler bandwidth,doppler domain,doppler radar,radar platform position changing,fdrf,sliding spotlight (ss) synthetic aperture radar (sar),range-frequency-dependent reference function,azimuth deramping,phase ramp,azimuth zero-padding,stripmap mode,two-step focusing,stepped frequency chirps,subband echo multiplication,two-step focusing approach,z transforms,chirp z transform,stepped frequency chirp,chirp $z$ transform (czt),radar imaging,image formation processing,doppler effect,bandwidth,azimuth,chirp | Radar,Continuous-wave radar,Radar imaging,Side looking airborne radar,Synthetic aperture radar,Remote sensing,Azimuth,Inverse synthetic aperture radar,Chirp,Mathematics | Journal |
Volume | Issue | ISSN |
11 | 10 | 1545-598X |
Citations | PageRank | References |
2 | 0.40 | 5 |
Authors | ||
6 |
Name | Order | Citations | PageRank |
---|---|---|---|
Xiulian Luo | 1 | 9 | 1.69 |
Yunkai Deng | 2 | 292 | 54.84 |
Robert Wang | 3 | 393 | 54.64 |
Wei Xu | 4 | 35 | 5.14 |
Y. Luo | 5 | 22 | 3.71 |
Lei Guo | 6 | 7 | 0.96 |