Influence of Atmospheric Propagation Effects on Holographic Imaging Techniques

The U.S. Army is actively pursuing 3D active imaging techniques using laser sources emitting at 1.5 μm. This eyesafe short wave infrared (SWIR) waveband is advantageous due to both the improved eye safety and atmospheric propagation through obscurants. NVESD has several active programs in this area, which will be reviewed in this paper. These are: 1) single-pixel scanned imaging laser radar, 2) 2D gated SWIR imaging, and 3) 3D-flash laser radar. These systems are being evaluated for various targeting scenarios, including as potential payloads on unmanned air-vehicles, ground vehicles and other sensor suites. Applications include low-cost long-range target identification, identification of heavily obscured targets, obstacle avoidance, and high resolution imaging.

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Assessment of Atmospheric Propagation Effects in SAR Images

IEEE Transactions on Geoscience and Remote Sensing ◽

10.1109/tgrs.2009.2022271 ◽

2009 ◽

Vol 47 (10) ◽

pp. 3507-3518 ◽

Cited By ~ 50

Author(s):

A. Danklmayer ◽

B.J. Doring ◽

M. Schwerdt ◽

M. Chandra

Keyword(s):

Sar Images ◽

Atmospheric Propagation ◽

Propagation Effects

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Three-Dimensional Holographic Imaging Using Single Frequency Microwave Data

International Journal of Antennas and Propagation ◽

10.1155/2018/6542518 ◽

2018 ◽

Vol 2018 ◽

pp. 1-14 ◽

Cited By ~ 7

Author(s):

Reza K. Amineh ◽

Maryam Ravan ◽

Raveena Sharma ◽

Smit Baua

Keyword(s):

3D Imaging ◽

Imaging Techniques ◽

Three Dimensional ◽

Single Frequency ◽

Low Frequencies ◽

Reconstruction Process ◽

Security Screening ◽

Holographic Imaging ◽

Wave Imaging ◽

The Media

Three-dimensional (3D) microwave and millimeter wave imaging techniques based on the holographic principles have been successfully employed in several applications such as security screening, body shape measurement for the apparel industry, underground imaging, and wall imaging. The previously proposed 3D holographic imaging techniques require the acquisition of wideband data over rectangular or cylindrical apertures. Requirement for wideband data imposes limitations on the hardware (in particular at very high or very low frequencies). It may also lead to errors in the produced images if the media is dispersive (e.g., in biomedical imaging) and not modeled properly in the image reconstruction process. To address these limitations, here, we propose a technique to perform 3D imaging with single frequency data. Instead of collecting data at multiple frequencies, we acquire the backscattered fields with an array of resonant antennas. We demonstrate the possibility of 3D imaging with the proposed setup and perform a comprehensive study of the capabilities and limitations of the technique via simulations. To perform a realistic study, the simulation data is contaminated by noise.

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