VOL. 18, NO. 3, MAY 2023
Reno, NV 89511, U.S.A.
MAY 2023 VOLUME 18 NUMBER 3 IJMOT ISSN: 1553-0396
Banmali S Rawat


Manuscript Title:Wideband Six-Port Reflectometer for Microwave Applications
Manuscript Id:IJMOT-2022-11-312454
In this paper, a wideband reflectometer based on six-port technology is presented. The designed six-port junction is built by using a modified ring power divider and three identical 90-degree hybrid couplers. The main difference from its initial application as a conventional six-port reflectometer is the addition of a fourth qi point. Here, the four power detectors are used to find the reflection coefficient (4 qi points) and a fifth detector is added as a reference. To simplify the fabrication process and minimize the cost, the six-port circuit is designed on a single-layer PCB. The measured results of the six-port junction reveal high performance over a large frequency band from 2.2 to 3.55 GHz. In order to evaluate its performance for real-time measurements, the proposed six-port reflectometer is then tested by measuring the reflection coefficient of different devices under test (DUTs). The measured results are then corrected by a simplified calibration method to have optimal results. Compared to conventional six-port calibration methods, the proposed calibration process is simple and allows accurate reflection coefficient measurements. After calibration, there is a great improvement in the corrected results of the reflection coefficient compared to the measured results which proves that the calibration process works perfectly from 2.6 to 3.8 GHz.
Authors:Rabih Barakat, Serioja Ovidiu Tatu
Submitted On:13-11-2022
Action: [Full Paper] No. of Downloads: 75
Manuscript Title:UWB MIMO Antenna with Enhanced Isolation using SRR
Manuscript Id:IJMOT-2022-11-312458
In this article a novel tiny UWB antenna was designed. An antenna one being considered, operating bandwidth is from 0.1 to 8.2 GHz. It is extended to 2 × 2 MIMO antenna. The spacing between the two antennas is 0.05?0. SRR is introduced between the two elements. Mutual coupling is below -15 dB from 0.1 to 8 GHz. How well MIMO antennae perform in terms of diversity gain, envelope correlation coefficient, gain, effective diversity gain, Channel capacity loss and radiation pattern also considered. It is also observed that the findings of the simulation and the measurements are found to be in good agreement.
Authors:K.VenuGopal, Y. Srinivasa Rao
Submitted On:22-11-2022
Action: [Full Paper] No. of Downloads: 74
Manuscript Title:Miniature Square Koch Fractal Folded-Slot Antenna for the 3.5 GHz IMT Range
Manuscript Id:IJMOT-2022-12-312468
In this paper, a miniature fractal folded-slot antenna based on Square Koch fractal geometry is presented. The started folded-slot antenna which measures 30×28 mm² is designed using CPW technology on Epoxy FR4 substrate characterized by a dielectric constant of 4.3 and a thickness of 0.76 mm. The started antenna is designed to operate at the 3.4 - 3.6 GHz band included in the 3.5 GHz international mobile telecommunication (IMT) range. The second iteration fractal antenna which is obtained by using the square Koch curve and operates at the same frequency band, while the size is reduced to 25×20mm². The miniaturization rate achieved then 60 %. The designed antenna is fabricated and tested. A good match is obtained between measurements and EM simulation results.
Authors: Bouchra Ezzahry, Tajeddin Elhamadi, Naima Amar Touhami, Mohamed Lamsalli
Submitted On:05-12-2022
Action: [Full Paper] No. of Downloads: 34
Manuscript Title:Metamaterial Embedded Multi-Notched Ultra-Wideband Monopole Antenna
Manuscript Id:IJMOT-2023-1-322480

Proposal and comprehension of spur line embedded frequency notched Ultrawideband antenna is projected in this paper. The performance of the antenna is enhanced by using square shaped metamaterial. Quarter-wavelength long spur line (lines) on the feeding microstrip line of UWB antenna backs a notch-filtering action to provide single/double/triple notch (notches) within the UWB spectrum of the antenna. The planned method is very simple and radiator independent. The conventional monopole antenna is loaded with square shaped metasurface (MS) to enhance the performance of the antenna. With and without metamaterial loaded single, double and triple spur-line embedded microstrip fed circular monopole antennas are separately designed, fabricated and measured. All the deliberate models are fabricated and considered for measurement of impedance and radiation characteristics .Measured results show very good consistency with that of results obtained from full wave simulation.

Authors:Susobhan Ray, Chittajit Sarkar, Khushi Banerjee, Mahuya Maity, Ipsita Ghosh, Sayantani Datta
Submitted On:16-01-2023
Action: [Full Paper] No. of Downloads: 54
Manuscript Title:Frequency-Reconfigurable Flexible Antenna for IoT On-Body Applications
Manuscript Id:IJMOT-2023-1-332479
In this paper, a flexible on-body antenna with frequency reconfigurability for multi-purposes is proposed. The proposed antenna has a hexagon-like shape with an on/off short to the ground. It switches between the ISM frequencies 433 MHz (when the switch is on) and 915 MHz (when the switch is off). It works as an on-body receiver for Wireless Capsule Endoscopy (WCE) system implemented at 433 MHz and as a receiver for implanted arm antenna implemented at 915 MHz. The proposed antenna is simulated on a cylindrical phantom of the average dielectric constant of skin, fats, and muscle. The effect of varying the bending radii is studied as well. The proposed antenna is fabricated and then tested on a liquid replicating the average biological material and on the human arm as well. The measured reconfigurable antenna gives good matching at both 446 MHz and 934 MHz. It also matched well on the human arm at the OFF state. Moreover, the fabricated on-body antenna at the ON state is tested as a receiver for the WCE system. The proposed antenna is fabricated on Rogers 5880 laminate and attains a size of 45 × 65 mm2.
Authors:Shaimaa A. Osman, Mohamed S. El-Gendy, Hadia M. Elhennawy, Esmat A. Abdallah
Submitted On:18-01-2023
Action: [Full Paper] No. of Downloads: 46
Manuscript Title:Gain Enhancement at Selective Frequency of HMSIW Based Leaky Wave Antenna
Manuscript Id:IJMOT-2023-1-332481

In the proposed paper a Substrate Integrated Waveguide in Half Mode (HMSIW) is designed for making a novel leaky wave antenna which was further analysed. The novel leaky wave antenna is designed with periodic variation in the longitudinal slots in the upper part of the substrate in a selective frequency along with band pass filter in the particular range with pass band at Centre frequency of 16.8GHz, 24.7GHz and 28.6GHz. The Filter is designed with the use of Defective Ground plane (DGS) by cutting slots of SRR in the lower ground plane. The leaky wave antenna which has been suggested in paper resonates at 17GHz and 24.6GHz, which is very close to the operating mid frequency of the band pass filter which is 16.8GHz, 24.7GHz and 28.6GHz. By designing of leaky wave antenna in the proposed manner, various advantages can be obtained such as reduction in size, frequency selectivity, removal of unwanted noise with the help of band pass filter. The novelty which can be achieved in this proposed antenna is that it leads to gain enhancement up to 6dB and 8dB at selective frequency of 17GHz and 24.6GHz with the reduced size HMSIW in which further size reduction is achieved with the assistance of DGS in ground plane.

Authors:Rakhi Kumari, Shweta Srivastava
Submitted On:23-01-2023
Action: [Full Paper] No. of Downloads: 23
Manuscript Title:Bow-Tie Antenna with Improved Performance for Advanced GPR Applications
Manuscript Id:IJMOT-2023-1-332483

This manuscript presents a low-profile bowtie antenna loaded by a rectangular array of artificial magnetic conductor metasurface (AMC) for ground penetrating radar (GPR) applications. The proposed antenna operates from 200 MHz to 400 MHz, with stable radiation characteristics. Unconventionally in low-frequency GPR antennas, the AMC structure is placed directly at the backside of the substrate without any separation to maintain the antenna robustness. The analytical formula for reflection coefficient is introduced and compared to the full wave simulation to investigate AMC partial reflectivity at low frequencies. The prospective antenna has a size of 59.44 ×37.2 cm2 covering vast fractional bandwidth (FBW) of 79.4%. Furthermore, a back reflector is placed at 33.3 cm from the antenna to eliminate the back radiation, avoid unwanted clutters during the GPR measurements and increase the antenna gain. As a proof of concept, the proposed antenna is fabricated and measured illustrating good agreement between simulated and measured results. A GPR time domain analysis is presented to validate the antenna performance.

Authors:Gehan S.Shehata, Anwer S.Abd El-Hameed, Shereen M.Ebrahim, Mahmoud A.Mohana, Abbas M. Abbas
Submitted On:25-01-2023
Action: [Full Paper] No. of Downloads: 41
Manuscript Title:“HEART” Shaped Broadband Hybrid Patch Antenna
Manuscript Id:IJMOT-2023-2-332495

This article proposes broadband “HEART” shaped hybrid patch antenna with reduced sized slot loaded ground plane. Conventional circular patch is effectively augmented to “HEART” shape by adding two circular shaped radiating elements at suitable position of the patch. Two slots of rectangular shaped are optimally placed in the reduced ground plane for proper impedance matching over a frequency range. Combined effect of this technique introduces high gain, low profile and broadband antenna design. The physical and electrical dimensions of the proposed antenna are 29 mm × 32 mm × 1.6 mm and 0.266? × 0.241? ×0.0108? respectively, where ? indicates the wavelength of minimum frequency of operation. The suggested antenna exhibits impedance bandwidth of 5 GHz (from 2.5 GHz to 7.5 GHz) and resonating at 2.8 GHz, 3.4 GHz, 5.5 GHz and 6.9 GHz frequencies respectively. 100% fractional bandwidth and peak gain of 3.6dBi at 5.5 GHz and 6.9 GHz with enough stable patterns of E field and H field are obtained. The presented antenna design and simulation are done by CST software and the equivalent RLC circuit is modeled by using ADS software. The proposed antenna is developed on low cost FR-4 substrate (dielectric constant is 4.4, loss tangent is 0.02, and height is 1.6 mm) and then it is tested using standard microwave measurement setup. The suggested antenna may be attractive for use in various frequency bands like WiMAX (3.4–3.6 GHz and 5.5 GHz),from 3.3GHz to 4.2GHz n77 frequency band, from 3.3GHz to 3.8 GHz n78 frequency band, from 4.4GHz to 5 GHz n79 frequency band and from 5.08 GHz to 5.73 GHz Wireless local area network frequency band. It also covers 5G-V2X band (3.3-5GHz), LTE 46 band (5.15-5.925GHz), short-range remote sensing, object positioning, high-bandwidth communications, VSAT etc.

Authors:Smarajit Maity, Tapas Tewary, Avisankar Roy, Kaushik Mandal, Sunandan Bhunia
Submitted On:14-02-2023
Action: [Full Paper] No. of Downloads: 36
Manuscript Title:A Compact Multiband Annular-Slotted Patch Rectenna for Efficient Energy Harvesting
Manuscript Id:IJMOT-2023-2-332496

In order to reduce the overreliance of electronic devices on energy storage medium, a multiband annular slotted microstrip patch antenna with a voltage multiplier rectifier circuit has been proposed in this research work. The proposed antenna resonant at 4.8 GHz, 5.1 GHz, 6.6 GHz, and 8.2 GHz, with reflection coefficients of -24.84 dB, -28.68 dB, -26.96 dB, and -16.36 dB, respectively. Furthermore, the proposed antenna achieved a -10 dB bandwidth of 850 MHz between 4.70 GHz and 5.56 GHz, 325 MHz between 6.43 GHz and 6.75 GHz, and 469 MHz between 8.05 GHz and 8.57 GHz, with gains of 3.42 dB, 2.78 dB, 5.91 dB, and 4.68 dB, respectively. The prototype is fabricated and the measured frequencies are 4.5 GHz, 5 GHz, 6.6 GHz, and 8 GHz, respectively. The proposed research finds potential in sensor networks, wireless devices, and other areas.

Authors:Neeru Kashyap, Dhawan Singh, Geetanjali
Submitted On:15-02-2023
Action: [Full Paper] No. of Downloads: 32
Manuscript Title:Low-Cost Portable System for Antenna Polarization Measurement
Manuscript Id:IJMOT-2023-2-332497
This paper presents the design of a standalone low-cost portable system to measure the polarization parameters of an antenna under test. The proposed system consists of a six-port network with two input ports and four output ports. The two input ports are connected to two identical linearly polarized wideband antennas. The two antennas are mounted to be orthogonal to each other. The four outputs are connected to wideband power detectors. These four outputs are proportional to the two input signals, the direct summation of the two input signals and the summation to the two input signals with a specified phase shift between them. These detected signals are used as inputs to an Arduino Mega 2560 microcontroller. This microcontroller uses these detected signals to determine the ratio between the horizontal and vertical components of the received signal and the phase shift between them. These values are used to determine the type of the polarization, the axial ratio, and the tilt angle of the received signal. These parameters are directly displayed on an LCD module connected to the microcontroller. On the other hand, a low-cost sweep signal generator kit ADF4351 is used as a source generator for the antenna under test. This sweep signal generator kit is synchronized with the microcontroller to present the measured parameters of the antenna under test on the LCD display directly as functions of frequency. This work proposes a novel portable and light weight polarization measurement system with low-cost and commercially available components. The proposed system is designed to operate in the frequency range from 2 to 4 GHz according to the bandwidth of its different parts. However, the design can be generalized to other frequency bands.
Authors:E.M. Eldesouki, S. A. M. Soliman, A. M. Attiya
Submitted On:16-02-2023
Action: [Full Paper] No. of Downloads: 31
Manuscript Title:Compact UWB Microstrip Patch Antenna for 5G Mobile Handset Applications
Manuscript Id:IJMOT-2023-3-332512
Herein, an ultra-wideband microstrip patch antenna for a 5G mobile handset is proposed. The proposed antenna is designed to operate in mm-Wave bands (27 – 75 GHz) with compact size (6×6 mm2). A square patch antenna, with rectangular slots of varying sizes, which is fed via coaxial cable, has been modified to operate within the frequency range of 27-32, 35-40, and 48-75 GHz, and yields an average gain of approximately 5 dB. 4-port MIMO antenna is proposed and printed on an FR-4 substrate with relative permittivity of 4.3, loss tangent of 0.025, and thickness of 0.8 mm with an overall size of 15×15×0.8 mm3. The mutual coupling between the radiating elements has been reduced using two-isolation techniques (hybrid technique), namely; zigzag-shaped parasitic line and partial ground structures. Using this new hybrid technique, the result was the coupling reduced up to -28 dB, 3×10-4 Envelop Correlation Coefficient (ECC), and diversity gain (DG) > 9.99 dB. The MIMO performance metrics such as envelope correlation coefficient and diversity gain are analyzed, which demonstrate good characteristic across the operating bandwidth. The proposed antenna design is simulated using CST microwave studio software and measured results reveal good agreement with the simulated ones.
Authors:Mai S. Abdel-Fattah, Ehab K. I. Hamad, Tamer G. Aboulnaga, Sherif A. Khaleel, Hala A. Elsadek
Submitted On:21-03-2023
Action: [Full Paper] No. of Downloads: 66
Manuscript Title:FBG Sensors for Temperature and Strain Measurement in Underground Coal Mines
Manuscript Id:IJMOT-2023-2-332499
Underground mining is a process that retrieves coal from deep below the earth surface sometimes as far as 500 meters. The Coal mine fire and deformation of roof strata caused by mining is the main reason behind a verity of coal mining accidents. During these mining methods, periodic strain and temperature monitoring is required. The Brillouin optical time domain reflectometry (BOTDR) techniques have been used as distributed network for temperature and strain detection in literature. In this paper, a new sensor layout in a distributed configuration using an optical Fiber Bragg grating sensor (FBG) is proposed for early detection of the strain and temperature. This sensor has been simulated to sense temperature and strain in the underground coal mines in a continuous manner. Focus is also made on methods for achieving higher transmission capacity by transmitting multiple sensed data simultaneously through a single channel. Also a distributed FBG sensor network has been proposed to determine one or more measurand at different locations in the entire coal mine. Analytical expressions for the minimum detectable power and hence the maximum detection distance are derived for such sensing in InGaAs PIN photodetectors in terms of the corresponding noise equivalent power (NEP) as the limiting case of received power. The analytical and simulated values of maximum distances are found to almost match.
Authors:Sagupha Parween, Aruna Tripathy
Submitted On:17-02-2023
Action: [Full Paper] No. of Downloads: 18
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