Array rotation aperture synthesis for short‐range imaging at millimeter wavelengths

Lucotte, Bertrand M.; Grafulla-González, Beatriz; Harvey, Andrew R.

doi:10.1029/2008rs003863

Cited by 7 publications

(9 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To get high cross-range resolutions and high dynamic ranges, more and more imaging systems explore irregular/random array designs to suppress the shadowing effects, which leads to irregular or/and nonuniform spatial sampling of the signals [1]- [3]. Meanwhile, some new imaging configurations, for instance, 3-D imaging with rotating arrays, synthesize a large planar aperture by rotating a small antenna array around a point on the aperture plane [4]- [7]. The synthetic arrays naturally acquire signals on an irregular grid in space.…”

Section: Introductionmentioning

confidence: 99%

NUFFT-Based Range Migration for 3-D Imaging with Irregular Planar Array

Wang

Yarovoy

2019

2019 International Conference on Electromagnetics in Advanced Applications (ICEAA)

View full text Add to dashboard Cite

In this paper, a Nonuniform fast Fourier transform (NUFFT)-based range migration algorithm (RMA) is proposed for three-dimensional (3-D) imaging with irregular planar arrays. The proposed imaging algorithm takes advantage of NUFFT to reconstruct the signal spectra in the wavenumber domain, which overcomes the constraint of irregular spatial sampling on the utilization of Fourier-based imaging algorithms. Compared to the conventional coherent summation algorithms, i.e., backprojection and Kirchhoff migration, it is a very efficient method for 3-D image formation with nonuniform spatial sampling. To demonstrate its imaging performance, some numerical simulations are presented and discussed.Index Terms-Nonuniform fast Fourier transform (NUFFT), planar array, nonuniform spatial sampling, range migration, three-dimensional(3-D) imaging.

show abstract

Section: Introductionmentioning

confidence: 99%

NUFFT-Based Range Migration for 3-D Imaging with Irregular Planar Array

Wang

Yarovoy

2019

2019 International Conference on Electromagnetics in Advanced Applications (ICEAA)

View full text Add to dashboard Cite

show abstract

“…Unfortunately, the rectangular visibility functions only can be measured by a few regular antenna arrays with serious baseline redundancy (such as the "T", "U" and "L" arrays). For utilizing the antennas more effectively, the antenna arrays used in the actual SAIR are irregular sparse arrays with fewer redundancy baselines, such as the "Y" array, rotation array, hexagonal and non-redundant arrays [7][8][9]. Generally, the visibility functions measured by these irregular sparse arrays are non-uniform.…”

Section: Introductionmentioning

confidence: 99%

Regularization Imaging Algorithm With Accurate G Matrix for Near-Field MMW Synthetic Aperture Imaging Radiometer

Chen¹,

Li²,

Wang³

et al. 2014

PIER B

View full text Add to dashboard Cite

Abstract-In order to improve the reconstruction accuracy of near-field SAIR, a novel regularization imaging algorithm based on an accurate G matrix is proposed in this paper. Due to the fact that the regularization reconstruction is usually an underdetermined problem, inaccurate operation matrix G will lead to great reconstruction error in the imaging results, or even the normal imaging cannot be obtained. In this paper, we establish an accurate G matrix based on the accurate imaging model of near-field SAIR. Compared with the traditional G matrix with some unnecessary approximations, the proposed G matrix without approximation can improve the reconstruction accuracy effectively. For improving the accuracy of matrix G further, the corresponding parameters are corrected according to the RMSE between the imaging results of the regularization method and modified FFT method which is not sensitive to the parameters' change. The effectiveness of this calibration method has been tested by 1D simulation experiments. Moreover, the 2D simulation experiments demonstrate that the proposed accurate G matrix can improve the imaging accuracy of regularization method effectively. Finally, the 1D imaging experiment is performed to test the effectiveness of the proposed method for the actual synthetic aperture imaging further.

show abstract

“…Finding an optimum number of antennas is important, since oversampling introduces unwanted noise to the system and can prove very expensive with the unnecessary antenna 13 , whilst undersampling could result in aliasing and reduced image sharpness. Furthermore, the simpler the configuration, the easier the system will be to calibrate 26 .…”

Section: Introductionmentioning

confidence: 99%

“…For instance, 19 used a Fourierbased imaging technique, explained in 25 , whilst 26 used genetic algorithms to optimise antenna arrays by rotational scanning. A popular method 12,27,28 is to adapt visible light ray tracing packages to millimetre wave conditions using physical optics.…”

Section: Introductionmentioning

confidence: 99%

“…The recent availability of low-cost integrated circuits designed for the communication sector means this option brings the cost down 17 . In one study 19 ,frequencies in the range [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] GHz range are used to monitor people on a conveyor. At this range, body temperature does not need to be considered, unlike for waves in the THz range.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

A methodology for the optimisation of a mm-wave scanner

2016

View full text Add to dashboard Cite

The need to detect non-metallic items under clothes to prevent terrorism at transport hubs is becoming vital. Millimetre wave technology is able to penetrate clothing, yet able to interact with objects concealed underneath. This paper considers active illumination using multiple transmitter and receiver antennas. The positioning of these antennas must achieve full body coverage, whilst minimising the number of antenna elements and the number of required measurements. It sets out a rapid simulation methodology, based on the Kirchhoff equations, to explore different scenarios for scanner architecture optimisation.The paper assumes that the electromagnetic waves used are at lower frequencies (say, 10-30 GHz) where the body temperature does not need to be considered. This range allows better penetration of clothing than higher frequencies, yet still provides adequate resolution.Since passengers vary greatly in shape and size, the system needs to be able to work well with a range of body morphologies. Thus we have used two very differently shaped avatars to test the portal simulations. This simulation tool allows many different avatars to be generated quickly.Findings from these simulations indicated that the dimensions of the avatar did indeed have an effect on the pattern of illumination, and that the data for each antenna pair can easily be combined to compare different antenna geometries for a given portal architecture, resulting in useful insights into antenna placement. The data generated could be analysed both quantitatively and qualitatively, at various levels of scale.

show abstract

Array rotation aperture synthesis for short‐range imaging at millimeter wavelengths

Cited by 7 publications

References 20 publications

NUFFT-Based Range Migration for 3-D Imaging with Irregular Planar Array

NUFFT-Based Range Migration for 3-D Imaging with Irregular Planar Array

Regularization Imaging Algorithm With Accurate G Matrix for Near-Field MMW Synthetic Aperture Imaging Radiometer

A methodology for the optimisation of a mm-wave scanner

Contact Info

Product

Resources

About