scholarly journals A Directional Antenna in a Matching Liquid for Microwave Radar Imaging

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Saeed I. Latif ◽  
Daniel Flores Tapia ◽  
Diego Rodriguez Herrera ◽  
Mario Solis Nepote ◽  
Stephen Pistorius ◽  
...  

The detailed design equations and antenna parameters for a directional antenna for breast imaging are presented in this paper. The antenna was designed so that it could be immersed in canola oil to achieve efficient coupling of the electromagnetic energy to the breast tissue. Ridges were used in the horn antenna to increase the operating bandwidth. The antenna has an exponentially tapered section for impedance matching. The double-ridged horn antenna has a wideband performance from 1.5 GHz to 5 GHz (3.75 GHz or 110% of impedance bandwidth), which is suitable for breast microwave radar imaging. The fabricated antenna was tested and compared with simulated results, and similar bandwidths were obtained. Experiments were conducted on breast phantoms using these antennas, to detect a simulated breast lesion. The reconstructed image from the experiments shows distinguishable tumor responses indicating promising results for successful breast cancer detection.

Materials ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 4918
Author(s):  
Amran Hossain ◽  
Mohammad Tariqul Islam ◽  
Md. Tarikul Islam ◽  
Muhammad E. H. Chowdhury ◽  
Hatem Rmili ◽  
...  

In this paper, a compact planar ultrawideband (UWB) antenna and an antenna array setup for microwave breast imaging are presented. The proposed antenna is constructed with a slotted semicircular-shaped patch and partial trapezoidal ground. It is compact in dimension: 0.30λ × 0.31λ × 0.011λ, where λ is the wavelength of the lowest operating frequency. For design purposes, several parameters are assumed and optimized to achieve better performance. The prototype is applied in the breast imaging scheme over the UWB frequency range 3.10–10.60 GHz. However, the antenna achieves an operating bandwidth of 8.70 GHz (2.30–11.00 GHz) for the reflection coefficient under–10 dB with decent impedance matching, 5.80 dBi of maximum gain with steady radiation pattern. The antenna provides a fidelity factor (FF) of 82% and 81% for face-to-face and side-by-side setups, respectively, which specifies the directionality and minor variation of the received pulses. The antenna is fabricated and measured to evaluate the antenna characteristics. A 16-antenna array-based configuration is considered to measure the backscattering signal of the breast phantom where one antenna acts as transmitter, and 15 of them receive the scattered signals. The data is taken in both the configuration of the phantom with and without the tumor inside. Later, the Iteratively Corrected Delay and Sum (IC–DAS) image reconstructed algorithm was used to identify the tumor in the breast phantom. Finally, the reconstructed images from the analysis and processing of the backscattering signal by the algorithm are illustrated to verify the imaging performance.


2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Mahdi Jalali ◽  
Tohid Sedghi ◽  
Shahin Shafei

A novel configuration of a printed monopole antenna with a very compact size for satisfying WLAN operations at the 5.2/5.8 GHz and also for X-band operations at the 10 GHz has been proposed. The antenna includes a simple square-shaped patch as the radiator, the rotated U-shaped conductor back plane element with embedded strip on it, and the partial rectangular ground surface. By using the rotated U-shaped conductor-backed plane with proper values, good impedance matching and improvement in bandwidth can be achieved, at the lower and upper bands. The impedance bandwidth forS11<-10 dB is about 1.15 GHz for 5 GHz band and 5.3 GHz for X-band. The measured peak gains are about 1.9 dBi at WLAN-band and 4.2 dBi at X-band. The experimental results represent that the realized antenna with good omnidirectional radiation characteristics, enough impedance bandwidth, and reasonable gains can be appropriate for various applications of the future developed technologies and handheld devices.


Author(s):  
B. Hammache ◽  
A. Messai ◽  
I. Messaoudene ◽  
T. A. Denidni

Abstract In this paper, a compact stepped slot antenna for ultra-wideband (UWB) applications is proposed. A very small size and UWB bandwidth operation are achieved by integrating a stepped slot in the back side of the antenna. This stepped slot is excited by using a 50 Ω-feed line in the top side of the antenna. The antenna is characterized by an impedance bandwidth between 3.05 GHz and more than 12 GHz. The dimensions of the antenna are 17 mm × 8 mm × 1.27 mm, which leads to the most compact size compared with other works in the literature. The integrated stepped slot is divided into additional elementary slots, where each elementary slot has a matching point. Adding these elementary slots allows to increase further the operating bandwidth. The radiation pattern of the compact stepped slot antenna is omnidirectional in the H-plane and bidirectional in the E-plane. The measurement results agree well with the simulated ones in terms of impedance matching and radiation pattern.


2017 ◽  
Vol 9 (10) ◽  
pp. 2013-2018 ◽  
Author(s):  
Md Zulfiker Mahmud ◽  
Mohammad Tariqul Islam ◽  
Md Naimur Rahman ◽  
Touhidul Alam ◽  
Md Samsuzzaman

A novel compact directional antenna with improved gain is proposed for microwave breast imaging (MBI) applications. The radiating fins are modified by etching several slots to make the antenna compact and enhance antenna performance in terms of bandwidth, gain, efficiency, and directivity. Several parameters are studied and optimized to frequency from 3.1 to 6.5 GHz, which is typically used in the breast imaging system. The electrical length of the antenna is 0.39λ × 0.46λ × 0.01λ at the lower frequency band. The result shows that the antenna exhibits −10 dB impedance bandwidth of 4.3 GHz (2.7–7 GHz) with directional radiation pattern. The peak gain of the proposed prototype is 7.8 dBi and fractional bandwidth is 92%. The time domain results show that the fidelity factor for face to face is 0.92 and for side by side is 0.62, which prove the directivity and lower distortion of the signal. The proposed prototype is successfully simulated, fabricated, and measured.


2014 ◽  
Vol 7 (6) ◽  
pp. 747-752 ◽  
Author(s):  
Mahmoud Abdipour ◽  
Saba Kazemi Alishahi ◽  
Kambiz Noormohammadi

In this paper, the design of a broadband multi-layer microstrip antenna is presented. The broadband characteristics are the results of coupled resonances of the patch and transmission line through the resonant aperture. For this purpose, a cross-shaped transmission line, a ring slot, and a shaped ring patch are used. The simulation and measurement results indicate that a wide impedance bandwidth of 70% for |S11| < −10 dB and a perfect impedance matching 35% for |S11| < −20 dB are achieved. The gain is stable over the impedance bandwidth. The maximum gain of the proposed antenna is 8.8 dBi at 5 GHz. The radiation pattern, radiation efficiency, and cross-polarization are also suitable throughout the impedance bandwidth.


Frequenz ◽  
2020 ◽  
Vol 74 (5-6) ◽  
pp. 191-199
Author(s):  
M. K. Verma ◽  
Binod K. Kanaujia ◽  
J. P. Saini ◽  
Padam S. Saini

AbstractA broadband circularly polarized slotted square patch antenna with horizontal meandered strip (HMS) is presented and studied. The HMS feeding technique provides the good impedance matching and broadside symmetrical radiation patterns. A set of cross asymmetrical slots are etched on the radiating patch to realize the circular polarization. An electrically small stub is added on the edge of the antenna for further improvement in performance. Measured 10-dB impedance bandwidth (IBW) and 3-dB axial ratio bandwidth (ARBW) of the proposed antenna are 32.31 % (3.14–4.35 GHz) and 20.91 % (3.34–4.12 GHz), respectively. The gain of the antenna is varied from 3.5 to 4.86dBi within 3-dB ARBW. Measured results matched well with the simulated results.


2019 ◽  
Vol 77 ◽  
pp. 115-123 ◽  
Author(s):  
Yang Yang ◽  
Lianghao Guo ◽  
Qing Zhou ◽  
Zhe Wu ◽  
Haibo Jiang ◽  
...  

Author(s):  
Shweta Rani ◽  
Sushil Kakkar

This paper focuses on the design and development of modified Koch fractal antenna. Compared to traditional Koch curve antenna, the presented antenna possesses a greater number of frequency bands and better impedance matching. Furthermore, the bacterial foraging optimization (BFO) approach is implemented to enhance the impedance bandwidth. The developed technique has been verified by employing various numerical simulations. The design parameters generated from the optimization procedure have been utilized to manufacture the antenna and the respective experimental and simulated results compared. The measured results show that the designed antenna exhibits multi and wideband behavior, covering WLAN, WIMAX, and various other wireless applications.


2018 ◽  
Vol 7 (2) ◽  
pp. 68-75 ◽  
Author(s):  
P. N. Vummadisetty ◽  
A. Kumar

This research article presents, a compact 0.19 λ x 0.32 λ size ACS fed printed monopole wideband antenna loaded with multiple radiating branches suitable for LTE2300/WiBro, 5 GHz WLAN and WiMAX applications. The proposed triple band uniplanar antenna encompasses of C shaped strip, L shaped strip, rectangular shaped strip and a lateral ground plane. All the radiating strips and ground plane are etched on the 26 × 15 m size low cost FR4 epoxy substrate. This designed geometry evoked three independent reonances at 2.3 GHz, 3.5 GHz and 5.5 GHz with precise impedance matching over each operating band. The reflection coefficient ( ) response of the presented antenna demonstrates three distinct resonant modes associated with -10 dB bandwidths are about 2.24-2.40 GHz, 3.38-3.83 GHz and 5.0-6.25 GHz respectively. From the study, it is also observed that the proposed design works perfect with microstrip as well as CPW feedings. Hence the designed Multi Feed Multi Band (MFMB) antenna can be easily deployed in to any portable wireless device that works for 2.3/3.5/ 5 GHz frequency bands.


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