Optimal Design of the Reflector Antenna to Improve Performance of C-Band Quad-Pol ScanSAR Systems

The performance of synthetic aperture radar (SAR) antenna determines the quality of images obtained from the spaceborne SAR system, and thus, SAR antenna should be designed to satisfy the target performance of SAR system. The performance indicators of a SAR system, such as ambiguity-to-signal ratio and resolution, also depend on the SAR operation mode. Therefore, it is important to consider the operation mode when designing an SAR antenna. In this paper, we analyzed the SAR antenna’s effect on ScanSAR (scanning synthetic aperture radar) which is a representative wide-swath mode and its quadrature-polarimetric (quad-pol) mode. In addition, we confirmed that the optimal reflector antenna for the C-band quad-pol ScanSAR system can be designed by analyzing the relation between the antenna size and the system performance.

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A test of airborne, side-looking synthetic-aperture radar in central Newfoundland for geological reconnaissance

Canadian Journal of Earth Sciences ◽

10.1139/e91-025 ◽

1991 ◽

Vol 28 (2) ◽

pp. 257-265 ◽

Cited By ~ 14

Author(s):

D. F. Graham ◽

D. R. Grant

Keyword(s):

Surface Roughness ◽

Synthetic Aperture Radar ◽

Three Dimensional ◽

Synthetic Aperture ◽

Structural Elements ◽

Terrain Classification ◽

Regional Trends ◽

Valuable Complement ◽

Wide Swath ◽

Aperture Radar

Side-looking, C-band synthetic-aperture radar (SAR) penetrates cloud and fog, and operates day or night, to produce pseudo-three-dimensional terrain images with enhanced topography and surface roughness. The images, which have a 20 m resolution and cover large areas, have been used to map the regional trends, patterns of lineaments, and terrain types over a 6200 km2 area of complex lithology, structure, and drift cover. Four lineament classes are differentiated. Glacial trends are clear, and bedrock structures (faults, fractures, joints, foliation, and folded bedding) with relief expression at the surface show through the drift as lineaments. They accurately reproduce most known features when compared with bedrock and Quatenary geology maps. Hitherto unrecognized structural elements are revealed. Tones and textures reflect minute surface roughness variations useful in terrain classification. SAR wide-swath-mode imagery is thus a valuable complement to aerial photography, and is superior in revealing hummocky moraine, ribbed moraine, boulder fields and stony till. Wider use of this imagery is encouraged.

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A Novel Orthogonal Waveform Separation Scheme for Airborne MIMO-SAR Systems

Sensors ◽

10.3390/s18103580 ◽

2018 ◽

Vol 18 (10) ◽

pp. 3580 ◽

Cited By ~ 1

Author(s):

Jie Wang ◽

Ke-Hong Zhu ◽

Li-Na Wang ◽

Xing-Dong Liang ◽

Long-Yong Chen

Keyword(s):

Remote Sensing ◽

High Resolution ◽

Synthetic Aperture Radar ◽

3D Imaging ◽

Synthetic Aperture ◽

Separation Scheme ◽

Sar Images ◽

Wide Swath ◽

Aperture Radar

In recent years, multi-input multi-output (MIMO) synthetic aperture radar (SAR) systems, which can promote the performance of 3D imaging, high-resolution wide-swath remote sensing, and multi-baseline interferometry, have received considerable attention. Several papers on MIMO-SAR have been published, but the research of such systems is seriously limited. This is mainly because the superposed echoes of the multiple transmitted orthogonal waveforms cannot be separated perfectly. The imperfect separation will introduce ambiguous energy and degrade SAR images dramatically. In this paper, a novel orthogonal waveform separation scheme based on echo-compression is proposed for airborne MIMO-SAR systems. Specifically, apart from the simultaneous transmissions, the transmitters are required to radiate several times alone in a synthetic aperture to sense their private inner-aperture channels. Since the channel responses at the neighboring azimuth positions are relevant, the energy of the solely radiated orthogonal waveforms in the superposed echoes will be concentrated. To this end, the echoes of the multiple transmitted orthogonal waveforms can be separated by cancelling the peaks. In addition, the cleaned echoes, along with original superposed one, can be used to reconstruct the unambiguous echoes. The proposed scheme is validated by simulations.

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