Compressive sensing imaging at Sub-THz frequency in transmission mode

Date

2017-01-01

Author

Özkan, Vedat Ali
Menteşe, Yıldız
Takan, Taylan
Şahin, Asaf Behzat
Altan, Hakan

Metadata

Show full item record

Item Usage Stats

277
views

0
downloads

Due to lack of widespread array imaging techniques in the THz range, point detector applications coupled with spatial modulation schemes are being investigated using compressive sensing (CS) techniques. CS algorithms coupled with innovative spatial modulation schemes which allow the control of pixels on the image plane from which the light is focused onto single pixel THz detector has been shown to rapidly generate images of objects. Using a CS algorithm, the image of an object can be reconstructed rapidly. Using a multiplied Schottky diode based multiplied millimeter wave source working at 113 GHz, a metal cutout letter F, which served as the target was illuminated in transmission. The image is spatially discretized by laser machined, 10 × 10 pixel metal apertures to demonstrate the technique of spatial modulation coupled with compressive sensing. The image was reconstructed by modulating the source and measuring the transmitted flux through the metal apertures using a Golay cell. Experimental results were compared to reference image to assess reconstruction performance using χ2 index. It is shown that a satisfactory image is reconstructed below the Nyquist rate which demonstrates that after taking into account the light intensity distribution at the image plane, compressive sensing is an advantageous method to be employed for remote sensing with point detectors.

Subject Keywords

Terahertz, Compressive Sensing, Imaging

URI

https://link.springer.com/chapter/10.1007/978-94-024-1093-8_7
https://hdl.handle.net/11511/76972

Relation

THz for CBRN and Explosives Detection and Diagnosis

Collections

Department of Physics, Book / Book chapter

Suggestions

OpenMETU
Core

Compressive sensing methods for multi-contrast magnetic resonance imaging Güngör, Alper; Yarman Vural, Fatoş Tunay; Çukur, Tolga; Department of Computer Engineering (2017) Compressive sensing (CS) is a signal processing tool that allows reconstruction of sparse signals from highly undersampled data. This study investigates application of CS to magnetic resonance imaging (MRI). In this study, first, an optimization framework for single contrast CS MRI is presented. The method relies on an augmented Lagrangian based method, specifically alternating direction method of multipliers (ADMM). The ADMM framework is used to solve a constrained optimization problem with an objective fu...
Compressive sensing imaging through a drywall barrier at sub-THz and THz frequencies in transmission and reflection modes Takan, Taylan; ÖZKAN, VEDAT ALİ; Idikut, Firat; Yildirim, Ihsan Ozan; ŞAHİN, ASAF BEHZAT; Altan, Hakan (2014-09-24) In this work sub-terahertz imaging using Compressive Sensing (CS) techniques for targets placed behind a visibly opaque barrier is demonstrated both experimentally and theoretically. Using a multiplied Schottky diode based millimeter wave source working at 118 GHz, metal cutout targets were illuminated in both reflection and transmission configurations with and without barriers which were made out of drywall. In both modes the image is spatially discretized using laser machined, 10 x 10 pixel metal aperture...
Image Reconstruction and Optimization Using a Terahertz Scanned Imaging System Yildirim, Ihsan Ozan; ÖZKAN, VEDAT ALİ; Idikut, Firat; Takan, Taylan; ŞAHİN, ASAF BEHZAT; Altan, Hakan (2014-09-23) Due to the limited number of array detection architectures in the millimeter wave to terahertz region of the electromagnetic spectrum, imaging schemes with scan architectures are typically employed. In these con fi gurations the interplay between the frequencies used to illuminate the scene and the optics used play an important role in the quality of the formed image. Using a multiplied Schottky-diode based terahertz transceiver operating at 340 GHz, in a stand-o ff detection scheme; the e ff ect of image q...
Equipotential projection based magnetic resonance electrical impedance tomography (mr-eit) for high resolution conductivity imaging Özdemir, Mahir Sinan; Eyüboğlu, Behçet Murat; Department of Electrical and Electronics Engineering (2003) In this study, a direct reconstruction algorithm for Magnetic Resonance Electrical Impedance Tomography (MR-EIT) is proposed and experimentally implemented for high resolution true conductivity imaging. In MR-EIT, elec trical impedance tomography (EIT) and magnetic resonance imaging (MRI) are combined together. Current density measurements are obtained making use of Magnetic Resonance Current Density Imaging (MR-CDI) techniques and peripheral potential measurements are determined using conventional EIT tech...
Frequency invariant beamforming and its application to wideband direction of arrival estimation Babataş, Eren; Candan, Çağatay; Department of Electrical and Electronics Engineering (2008) In this thesis the direction of arrival estimation of wideband signals using frequency invariant beamforming method is examined. The difficulty with the direction of arrival estimation of wideband signals is that it is not possible to obtain a single covariance matrix valid for the whole frequency spectrum of the signal. There are various methods proposed in the literature to overcome this difficulty. The common aim of all the methods is to obtain a composite covariance matrix for the overall band of the si...

Citation Formats

V. A. Özkan, Y. Menteşe, T. Takan, A. B. Şahin, and H. Altan, Compressive sensing imaging at Sub-THz frequency in transmission mode. 2017, p. 55.