Terahertz interferometric and synthetic aperture imaging

Bandyopadhyay, Aparajita; Stepanov, A. G.; Schulkin, Brian; Federici, Michael D.; Sengupta, Amartya; Gary, Dale E.; Federici, John F.; Barat, Robert; Michalopoulou, Zoi‐Heleni; Zimdars, David

doi:10.1364/josaa.23.001168

Cited by 45 publications

(35 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This far-field assumption is used for synthetic imaging and simplifies the imaging reconstruction process. However, most standoff THz applications do not fall in the 'far-field' limit [1], and the simplified inverse Fourier transform of the electric field correlation-the far-field image reconstruction-must be modified [14] to account for the curvature of the wave fronts in the near-field.…”

Section: Near-field Versus Far-fieldmentioning

confidence: 99%

Detection of explosives by Terahertz synthetic aperture imaging—focusing and spectral classification

Sinyukov

Zorych

Michalopoulou

et al. 2008

Comptes Rendus. Physique

Self Cite

View full text Add to dashboard Cite

Section: Near-field Versus Far-fieldmentioning

confidence: 99%

Detection of explosives by Terahertz synthetic aperture imaging—focusing and spectral classification

Sinyukov

Zorych

Michalopoulou

et al. 2008

Comptes Rendus. Physique

Self Cite

View full text Add to dashboard Cite

“…Various imaging technologies, such as urban sensing [1], [2] or terahertz imaging [3] require wideband near-field beamforming or imaging. Those applications use measurements from physical or synthetic sensor arrays to reconstruct images of a scene of interest.…”

Section: Introductionmentioning

confidence: 99%

Fast wideband near-field imaging with URAs applied to urban sensing

Leigsnering

Zoubir

Ghogho

2011

2011 4th IEEE International Workshop on Computational Advances in Multi-Sensor Adaptive Processing (CAMSAP)

View full text Add to dashboard Cite

High resolution wideband near-field imaging requires wideband signals and large array apertures. Hence, a large amount of data needs to be processed in the image formation step. The computational load of the standard delay and sum beamformer stems from the calculation of the focus delays and the evaluation of the sums over the measurements. We propose an approach tackling the problem of calculating the focus delays. Provided a uniform rectangular array (URA) is used, the image can be evaluated on a well tailored discrete grid such that most focus delays are redundant. Now by calculating only the non-redundant values we can reduce the numerical complexity significantly.The above approach is combined with fast beamforming based on the non-equispaced fast Fourier transform (NFFT). We demonstrate the good performance with experimental results from a through-the-wall radar imaging system.

show abstract

“…mirror to make a passive thermal image of the upper torso of a man [12]. Active images have also been considered [13][14][15], as have interferometric and synthetic aperture techniques [16,17].…”

Section: Introductionmentioning

confidence: 99%

Active and passive imaging in the THz spectral region: phenomenology, dynamic range, modes, and illumination

et al. 2008

View full text Add to dashboard Cite

The useful compromise between resolution and penetration power of the submillimeter or terahertz (THz) spectral region has long made it attractive for a variety of imaging applications. However, many of the demonstrations of imaging in this spectral region have used strategically oriented targets, especially favorable concealment materials, proximate imaging geometries, etc. This paper reports the results of studies aimed at better understanding the phenomenology of targets, the impact of this phenomenology on various active and passive imaging strategies, and most importantly, the development of imaging strategies that do not require the aforementioned special circumstances. Particular attention is paid to the relationship between active and passive images, especially with respect to how they interact with the illumination-and detector-mode structures of various imaging scenarios. It is concluded that the very large dynamic range that can be obtained with active single-mode systems (including focal-plane arrays) can be used in system designs to overcome the deleterious effects that result from the dominance of specular reflections in single-mode active systems as well as to strategically orient targets to obtain recognition. This will aid in the development of a much more robust and generally useful imaging technology in this spectral region.

show abstract

Terahertz interferometric and synthetic aperture imaging

Cited by 45 publications

References 33 publications

Detection of explosives by Terahertz synthetic aperture imaging—focusing and spectral classification

Detection of explosives by Terahertz synthetic aperture imaging—focusing and spectral classification

Fast wideband near-field imaging with URAs applied to urban sensing

Active and passive imaging in the THz spectral region: phenomenology, dynamic range, modes, and illumination

Contact Info

Product

Resources

About