scholarly journals Food Security Sensing System Using a Waveguide Antenna Microwave Imaging through an Example of an Egg

Sensors ◽  
2020 ◽  
Vol 20 (3) ◽  
pp. 699
Author(s):  
Tzu-Chun Tai ◽  
Hung-Wei Wu ◽  
Cheng-Yuan Hung ◽  
Yeong-Her Wang
Keyword(s):  
Food Security ◽  
Imaging System ◽  
Antenna System ◽  
Microwave Imaging ◽  
Dielectric Constants ◽  
Sensing System ◽  
High K ◽  
Scanning Area ◽  
High K Materials ◽  
Non Destructive

In this paper, we present a form of food security sensing using a waveguide antenna microwave imaging system through an example of an egg. A waveguide antenna system with a frequency range of 7–13 GHz and a maximum gain of 17.37 dBi was proposed. The maximum scanning area of the waveguide antenna microwave imaging sensing system is 30 × 30 cm2. In order to study the resolution and sensitivity of the waveguide antenna microwave imaging sensing system, the circular and triangular high-k materials (with the same thickness but with different dielectric constants of the materials) were used as the testing sample for observing the microwave images. By using the proposed waveguide antenna microwave imaging sensing system, the high-k materials with different dielectric constants and shapes could be easily sensed. Therefore, the waveguide antenna microwave imaging sensing system could be potentially used for applications in rapid, non-destructive food security sensing. Regarding the example of an egg, the proposed waveguide antenna microwave imaging sensing system could effectively identify the health status of many eggs very quickly. The proposed waveguide antenna microwave imaging sensing system provides a simple, non-destructive, effective, and rapid method for food security applications.

scholarly journals On the Use of Absorbing Metasurfaces in Microwave Imaging

2020 ◽  
Author(s):  
Ziqi Liu ◽  
Nozhan Bayat ◽  
Puyan Mojabi
Keyword(s):  
Inverse Scattering ◽  
Imaging System ◽  
Simulated Data ◽  
Antenna System ◽  
Microwave Imaging ◽  
Scattering Data ◽  
External Interference ◽  
Microwave Scattering ◽  
Advantages And Disadvantages ◽  
Background Medium

<p>Microwave imaging (MWI) systems are usually enclosed within casings, e.g., in order to contain the utilized coupling liquid or to help mount the antenna system. On the other hand, inverse scattering algorithms, which are used to process the measured microwave scattering data, often assume that the background medium of the imaging system extends to infinity (i.e., unbounded background medium assumption). Thus, they do not consider the reflections occurring at the system enclosure. For such algorithms to yield successful images, these reflections need to be minimized, e.g., via the use of a lossy coupling liquid. As an alternative to a lossy background medium which also reduces the desired signal level, this paper investigates the use of metallic-backed absorbing metasurfaces as the MWI system enclosure in order to (i) reduce these reflections, and also (ii) to shield the MWI system from external interference. Using simulated data, we then show that standard inverse scattering algorithms, employing the free-space assumption, can successfully process the data collected under the metasurface enclosure and yield acceptable permittivity images. The advantages and disadvantages of absorbing metasurface enclosure, along with the limitations of this study, will also be discussed. Finally, an absorbing metasurface is fabricated and its reflectivity is experimentally evaluated.</p>

High-k Materials for Advanced Gate Stack Dielectrics: a Comparison of ALCVD and MOCVD as Deposition Technologies

2003 ◽  
Vol 765 ◽  
Author(s):  
Matty Caymax ◽  
H. Bender ◽  
B. Brijs ◽  
T. Conard ◽  
S. DeGendt ◽  
...  
Keyword(s):  
Physical Vapor Deposition ◽  
Gate Dielectric ◽  
Dielectric Material ◽  
Dielectric Constants ◽  
Gate Stack ◽  
Interfacial Layers ◽  
High K ◽  
High K Materials ◽  
Gate Dielectric Material ◽  
Deposition Techniques

AbstractIn the quest for ever smaller transistor dimensions, the well-known and reliable SiO2 gate dielectric material needs to be replaced by alternatives whith higher dielectric constants in order to reduce the gate leakage. Candidate materials are metal oxides such as HfO2. Themost promising deposition techniques, next to Physical Vapor Deposition, appear to be ALCVD and MOCVD. In this paper, we compare the most important characteristics of layers from both proces techniques and assess their relevance to gate stack applications: density, crystallisation, impurities, growth mechanism, interfacial layers, dielectric constant, mobility. Although we find some minor differences, layers from both techniques mostly show striking similarities in many aspects, both positive and negative.

scholarly journals A Low Cost and Portable Microwave Imaging System for Breast Tumor Detection Using UWB Directional Antenna array

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
M. T. Islam ◽  
M. Z. Mahmud ◽  
M. Tarikul Islam ◽  
S. Kibria ◽  
M. Samsuzzaman
Keyword(s):  
Dielectric Properties ◽  
Breast Tumor ◽  
Breast Imaging ◽  
Imaging System ◽  
Low Cost ◽  
Microwave Imaging ◽  
Dielectric Constants ◽  
Ultra Wideband ◽  
Slot Antenna ◽  
Breast Phantom

Abstract Globally, breast cancer is a major reason for female mortality. Due to the limitations of current clinical imaging, the researchers are encouraged to explore alternative and complementary tools to available techniques to detect the breast tumor in an earlier stage. This article outlines a new, portable, and low-cost microwave imaging (MWI) system using an iterative enhancing technique for breast imaging. A compact side slotted tapered slot antenna is designed for microwave imaging. The radiating fins of tapered slot antenna are modified by etching nine rectangular side slots. The irregular slots on the radiating fins enhance the electrical length as well as produce strong directive radiation due to the suppression of induced surface currents that radiate vertically at the outer edges of the radiating arms with end-fire direction. It has remarkable effects on efficiency and gain. With the addition of slots, the side-lobe levels are reduced, the gain of the main-lobe is increased and corrects the squint effects simultaneously, thus improving the characteristics of the radiation. For experimental validation, a heterogeneous breast phantom was developed that contains dielectric properties identical to real breast tissues with the inclusion of tumors. An alternative PC controlled and microcontroller-based mechanical MWI system is designed and developed to collect the antenna scattering signal. The radiated backscattered signals from the targeted area of the human body are analyzed to reveal the changes in dielectric properties in tissues. The dielectric constants of tumorous cells are higher than that of normal tissues due to their higher water content. The remarkable deviation of the scattered field is processed by using newly proposed Iteratively Corrected Delay and Sum (IC-DAS) algorithm and the reconstruction of the image of the phantom interior is done. The developed UWB (Ultra-Wideband) antenna based MWI has been able to perform the detection of tumorous cells in breast phantom that can pave the way to saving lives.

scholarly journals On the Use of Absorbing Metasurfaces in Microwave Imaging

2020 ◽  
Author(s):  
Ziqi Liu ◽  
Nozhan Bayat ◽  
Puyan Mojabi
Keyword(s):  
Inverse Scattering ◽  
Imaging System ◽  
Simulated Data ◽  
Antenna System ◽  
Microwave Imaging ◽  
Scattering Data ◽  
External Interference ◽  
Microwave Scattering ◽  
Advantages And Disadvantages ◽  
Background Medium

<p>Microwave imaging (MWI) systems are usually enclosed within casings, e.g., in order to contain the utilized coupling liquid or to help mount the antenna system. On the other hand, inverse scattering algorithms, which are used to process the measured microwave scattering data, often assume that the background medium of the imaging system extends to infinity (i.e., unbounded background medium assumption). Thus, they do not consider the reflections occurring at the system enclosure. For such algorithms to yield successful images, these reflections need to be minimized, e.g., via the use of a lossy coupling liquid. As an alternative to a lossy background medium which also reduces the desired signal level, this paper investigates the use of metallic-backed absorbing metasurfaces as the MWI system enclosure in order to (i) reduce these reflections, and also (ii) to shield the MWI system from external interference. Using simulated data, we then show that standard inverse scattering algorithms, employing the free-space assumption, can successfully process the data collected under the metasurface enclosure and yield acceptable permittivity images. The advantages and disadvantages of absorbing metasurface enclosure, along with the limitations of this study, will also be discussed. Finally, an absorbing metasurface is fabricated and its reflectivity is experimentally evaluated.</p>

Determination of relative position of antenna system and RGB-D sensor in combined microwave imaging system

Antennas ◽  
2021 ◽  
Author(s):  
V. V. Razevig ◽  
S. I. Ivashov ◽  
А. S. Bugaev ◽  
A. V. Zhuravlev
Keyword(s):  
Computer Modeling ◽  
Relative Position ◽  
Imaging System ◽  
Antenna System ◽  
Microwave Imaging ◽  
Optical Data ◽  
Radar Signal ◽  
Radar Images ◽  
Base Points

Microwave imaging technique allows obtaining images of hidden objects in structures and media using microwaves. This technique has various applications such as: nondestructive testing, medical imaging, concealed weapon detection, through-the-wall imaging, etc. Obtaining radar images in these applications is based on processing phase and amplitude of the reflected signal recorded over an aperture (a microwave hologram). Recently, systems began to appear in which the radar part is supplemented by an RGB-D sensor, which allows to obtain new capabilities. For example, there is the a microwave screening system architecture in which inverse synthetic aperture is formed by the natural motion of the subject in the vicinity of a stationary linear antenna array. The microwave system is complemented with an synchronous RGB-D video sensor which captures the trajectory of the moving subject in 3D and allows coherent processing of the radar signal. Another system detects objects buried under irregular surface and uses RGB-D sensor for capturing the surface relief for suppressing reflection of the sounding signal from the surface. Calibration between a radar and an RGB-D sensor is an essential process for microwave and optical data fusion. This article presents a novel approach for calibration, using a planar calibration target which is made of radiotransparent material (such a foam plastic sheet) with square marker and six small metal balls embedded in target surface and representing point objects. The proposed method exploits 3D-3D correspondences between coordinates of point objects in two coordinate systems associated to the sensor and to the radar. One points set is extracted from optical data, using marked corners of the target as a base points. Second points set is obtained from microwave data as local maxima of 3D volume of data reconstructed from one-frequency microwave hologram. Computer modeling were performed using Autodesk 3ds Max software by which models of all components of the system were built and the optical image from the sensor was modeled. Test experiments were carried out using a measurement system composed of the following components: a compact vector network analyzer (VNA), two mechanical scanners with stepper motors, one transmitting and one receiving horn antennas, mounted on the VNA, an RGB-D sensor, a microcontroller board, and a computer. The high accuracy of the method is confirmed both by computer modeling and physical experiment. The accuracy of determination of relative position between the radar and the sensor is about one fifth of the signal wavelength used.

A Microwave Imaging System for the Detection of Targets Hidden behind Dielectric Walls

2020 ◽  
Author(s):  
Renato Cicchetti ◽  
Valentina Cicchetti ◽  
Sandra Costanzo ◽  
Paolo D'Atanasio ◽  
Alessandro Fedeli ◽  
...  
Keyword(s):  
Imaging System ◽  
Microwave Imaging

Advanced Non-Destructive Fault Isolation Techniques for PCB Substrates Using Magnetic Current Imaging and Terahertz Time Domain Reflectometry

2018 ◽  
Author(s):  
Daechul Choi ◽  
Yoonseong Kim ◽  
Jongyun Kim ◽  
Han Kim
Keyword(s):  
Time Domain ◽  
Quantum Interference ◽  
Flip Chip ◽  
Imaging System ◽  
Time Domain Reflectometry ◽  
Fault Isolation ◽  
Magnetic Current ◽  
Isolation Techniques ◽  
Super Conducting ◽  
Non Destructive

Abstract In this paper, we demonstrate cases for actual short and open failures in FCB (Flip Chip Bonding) substrates by using novel non-destructive techniques, known as SSM (Scanning Super-conducting Quantum Interference Device Microscopy) and Terahertz TDR (Time Domain Reflectometry) which is able to pinpoint failure locations. In addition, the defect location and accuracy is verified by a NIR (Near Infra-red) imaging system which is also one of the commonly used non-destructive failure analysis tools, and good agreement was made.

scholarly journals Microwave Imaging of Breast Skin Utilizing Elliptical UWB Antenna and Reverse Problems Algorithm

Micromachines ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 647
Author(s):  
Sameer Alani ◽  
Zahriladha Zakaria ◽  
Tale Saeidi ◽  
Asmala Ahmad ◽  
Muhammad Ali Imran ◽  
...  
Keyword(s):  
Skin Cancer ◽  
Imaging System ◽  
Signal Transmission ◽  
Similarity Index ◽  
Structural Similarity ◽  
Microwave Imaging ◽  
Ultra Wideband ◽  
Uwb Antenna ◽  
System A ◽  
High Structural Similarity

Skin cancer is one of the most widespread and fast growing of all kinds of cancer since it affects the human body easily due to exposure to the Sun’s rays. Microwave imaging has shown better outcomes with higher resolution, faster processing time, mobility, and less cutter and artifact effects. A miniaturized elliptical ultra-wideband (UWB) antenna and its semi-spherical array arrangement were used for signal transmission and reception from the defected locations in the breast skin. Several conditions such as various arrays of three, six, and nine antenna elements, smaller tumor, multi-tumors, and skin on a larger breast sample of 30 cm were considered. To assess the ability of the system, a breast shape container with a diameter of 130 mm and height of 60 mm was 3D printed and then filled with fabricated skin and breast fat to perform the experimental investigation. An improved modified time-reversal algorithm (IMTR) was used to recreate 2D images of tumors with the smallest radius of 1.75 mm in any location within the breast skin. The reconstructed images using both simulated and experimental data verified that the system can be a reliable imaging system for skin cancer diagnosis having a high structural similarity index and resolution.

Assessing a Microwave Imaging System for Brain Stroke Monitoring via High Fidelity Numerical Modelling

2021 ◽  
pp. 1-1
Author(s):  
David O. Rodriguez-Duarte ◽  
Jorge A. Tobon Vasquez ◽  
Rosa Scapaticci ◽  
Lorenzo Crocco ◽  
Francesca Vipiana
Keyword(s):  
Numerical Modelling ◽  
Imaging System ◽  
Microwave Imaging ◽  
High Fidelity ◽  
Brain Stroke
Sign in / Sign up

Export Citation Format

Share Document