Phaseless computational imaging with a radiating metasurface

Fromentèze, Thomas; Liu, Xiaojun; Boyarsky, Michael; Gollub, Jonah N.; Smith, David R.

doi:10.1364/oe.24.016760

Cited by 31 publications

(17 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…On the other hand, the Wirtinger Flow (WF) phase retrieval algorithm of [5] is used in [13] for microwave imaging with a frequency-diverse metasurface antenna. The antenna produces spatially diverse radiation patterns that vary as a function of the frequency sampled over the operational K-band (17.5-26.5 GHz).…”

Section: Introductionmentioning

confidence: 99%

Synthetic Aperture Imaging With Intensity-Only Data

Moscoso

Novikov

Papanicolaou

et al. 2020

IEEE Trans. Comput. Imaging

View full text Add to dashboard Cite

We consider imaging the reflectivity of scatterers from intensity-only data recorded by a single moving transducer that both emits and receives signals, forming a synthetic aperture. By exploiting frequency illumination diversity, we obtain multiple intensity measurements at each location, from which we determine field cross-correlations using an appropriate phase controlled illumination strategy and the inner product polarization identity. The field cross-correlations obtained this way do not, however, provide all the missing phase information because they are determined up to a phase that depends on the receiver's location. The main result of this paper is an algorithm with which we recover the field cross-correlations up to a single phase that is common to all the data measured over the synthetic aperture, so all the data are synchronized. Thus, we can image coherently with data over all frequencies and measurement locations as if full phase information was recorded.

show abstract

Section: Introductionmentioning

confidence: 99%

Synthetic Aperture Imaging With Intensity-Only Data

Moscoso

Novikov

Papanicolaou

et al. 2020

IEEE Trans. Comput. Imaging

View full text Add to dashboard Cite

show abstract

“…In addition to these methods, other methods demonstrated on TWI in the literature can be given as blind deconvolution [15], synthetic aperture radar (SAR) [16][17][18][19], noise radar [20,21], multiple signal classification (MUSIC) algorithm [22], uniform geometric theory of diffraction (UTD) technique [23], compressive sensing method [24], adaptive polarization contrast technique [25], self-injection-locked (SIL) radar [26] and shifted pixel method [27]. Phase-retrieval from intensity only measurements have recently gained significant traction [38][39][40][41]. Most of this research has focused on achieving phase retrieval on the software layer by means of using iterative algorithms, such as the Wirtinger Flow algorithm studied in [38,39].…”

Section: Introductionmentioning

confidence: 99%

“…Phase-retrieval from intensity only measurements have recently gained significant traction [38][39][40][41]. Most of this research has focused on achieving phase retrieval on the software layer by means of using iterative algorithms, such as the Wirtinger Flow algorithm studied in [38,39]. Indirect holographic imaging enables phase retrieval from intensity only measurements without the need for an additional reconstruction algorithm on the signal processing layer.…”

Section: Introductionmentioning

confidence: 99%

Indirect microwave holography and Through-Wall imaging

Yurduseven¹,

Elsdon²

2019

Frelsi

View full text Add to dashboard Cite

In this paper, a review of indirect microwave holography for through-wall imaging is presented. Indirect microwave holography is an imaging technique, enabling the complex object scattered fields (amplitude and phase) to be mathematically recovered from intensity-only, scalar microwave measurements. By removing the requirement to use vector measurement equipment to directly measure the complex fields, indirect microwave holography significantly reduces the cost of the imaging system and simplifies the hardware implementation. The application of a back-propagation algorithm enables the reconstructed amplitude and phase images to be obtained at the plane of the concealed object. In order to demonstrate the validity of the reviewed approach, experimental work is carried out on a metallic gun concealed under a 5 cm thick plywood wall and it is demonstrated that the indirect microwave holographic TWI can produce good resolution amplitude and phase images when back-propagation is applied. TWI of a concealed dielectric box representing non-metallic ordnance is also performed to demonstrate the ability of the technique to reconstruct through-wall images of concealed dielectric objects. An investigation of the resolution characteristics of the system suggests diffraction limited resolution can be achieved.

show abstract

“…Yet information transfer through complex media is crucial for many applications in telecommunications, imaging or medical therapies. Examples of a complex medium at optical frequencies include highly scattering opaque ones as well as biological tissues or multimode fibers [3][4][5][6][7][8]; in the microwave domain, forests or cities can be considered multiple scattering media, while reverberating media are also very common, ranging from reverberation chambers for electromagnetic compatibility tests, via open disordered cavities for computational imaging to indoor environments trapping wireless communication signals [9][10][11][12]. Numerous techniques, notably time reversal and wave front shaping [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27], have been proposed to take advantage of the multiple scattering and reveberation occuring during propagation.…”

mentioning

confidence: 99%

“…Moreover, transposing the concept of spatio-temporal wavefront shaping from optics to the microwave range, using very simple electronically controllable SMMs, may offer a wealth of applications. These could be found in the domains of radars, antennas, high power sources, imaging devices, or wireless communications for instance [10,11,34,35,38,39] …”

mentioning

confidence: 99%

Spatiotemporal Wave Front Shaping in a Microwave Cavity

Hougne¹,

Lemoult²,

Fink³

et al. 2016

Phys. Rev. Lett.

View full text Add to dashboard Cite

Controlling waves in complex media has become a major topic of interest, notably through the concepts of time reversal and wavefront shaping. Recently, it was shown that spatial light modulators can counter-intuitively focus waves both in space and time through multiple scattering media when illuminated with optical pulses. In this letter we transpose the concept to a microwave cavity using flat arrays of electronically tunable resonators. We prove that maximizing the Green's function between two antennas at a chosen time yields diffraction limited spatio-temporal focusing.Then, changing the photons' dwell time inside the cavity, we modify the relative distribution of the spatial and temporal degrees of freedom (DoF), and we demonstrate that it has no impact on the field enhancement: wavefront shaping makes use of all available DoF, irrespective of their spatial or temporal nature. Our results prove that wavefront shaping using simple electronically reconfigurable arrays of reflectors is a viable approach to the spatio-temporal control of microwaves, with potential applications in medical imaging, therapy, telecommunications, radar or sensing. They also offer new fundamental insights regarding the coupling of spatial and temporal DoF in complex media.

show abstract

Phaseless computational imaging with a radiating metasurface

Cited by 31 publications

References 26 publications

Synthetic Aperture Imaging With Intensity-Only Data

Synthetic Aperture Imaging With Intensity-Only Data

Indirect microwave holography and Through-Wall imaging

Spatiotemporal Wave Front Shaping in a Microwave Cavity

Contact Info

Product

Resources

About