Back to Search
Start Over
Focus FMCW SAR Data Using the Wavenumber Domain Algorithm.
- Source :
- IEEE Transactions on Geoscience & Remote Sensing; Apr2010 Part 2, Vol. 48 Issue 4, p2109-2118, 10p
- Publication Year :
- 2010
-
Abstract
- The combination of frequency-modulation continuous-wave (FMCW) technology and synthetic aperture radar (SAR) promises a lightweight, cost-effective, and high-quality imaging sensor for remote sensing. However, the long signal duration time leads to the failure of the conventional start/stop approximation of the pulsed SAR. In this paper, a signal model is proposed to address the effects of the continuous motion during the transmit time on the echoed signal. Based on the model, an analytical point target reference spectrum is derived. From the spectrum, it will be seen that the continuous motion introduces an additional range-azimuth coupling term and a range walk term compared with the conventional pulsed SAR. The range walk term is well known, whereas the foregoing range-azimuth coupling term is formulated for the first time in the FMCW SAR community. For the squint and spotlight modes, these range walk and range-azimuth coupling terms might significantly degrade the image quality. In this paper, based on the proposed analytical signal model, we further discuss the application of the wavenumber domain algorithm for the FMCW SAR data. In addition, different approximations of the Stolt mapping are made to highlight the effect of the range-dependent higher-order range-azimuth coupling terms on the 2-D impulse responses. Finally, X-band simulated experiments and Ka-band real FMCW SAR data are used to validate the signal model and the processing method. [ABSTRACT FROM AUTHOR]
- Subjects :
- CONTINUOUS wave radar
SYNTHETIC aperture radar
ALGORITHMS
REMOTE sensing
DETECTORS
Subjects
Details
- Language :
- English
- ISSN :
- 01962892
- Volume :
- 48
- Issue :
- 4
- Database :
- Complementary Index
- Journal :
- IEEE Transactions on Geoscience & Remote Sensing
- Publication Type :
- Academic Journal
- Accession number :
- 50915805
- Full Text :
- https://doi.org/10.1109/TGRS.2009.2034368