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2023-12-29
PIER C
Vol. 139, 197-209, 2024
download: 288
Simulation Research on Breast Tumor Model Based on Magnetoacoustic Concentration Tomography of Magnetic Nanoparticles with Magnetic Induction
Xiaoheng Yan , Fangtian Liu , Waldemar Tomasz Smolik , Xinxian Dan and Xiaohan Hou
Magnetic nanoparticles (MNPs) have been widely investigated as effective drug carriers for targeted tumor therapy. However, the successful application of this technology in the human body requires reliable imaging support. Magnetoacoustic Concentration Tomography of Magnetic Nanoparticles with Magnetic Induction (MACT-MI) is an electromagnetic-ultrasonic coupling imaging technique that holds great promise in improving imaging resolution and providing unique advantages for tumor monitoring and treatment. To evaluate the imaging feasibility of MACT-MI technology for targeted therapy of breast tumors, this study establishes a realistic breast model and takes into account the distribution of magnetic particles within the actual breast tissue environment. A concentration gradient model is introduced, and the finite element method is employed to solve the electromagnetic and sound fields. In addressing the research objective, the forward problem is investigated by analyzing the magnetic force and sound pressure distribution for various tumor sizes and locations, different breast tissues, and both benign and malignant tumors. The results obtained indicate that the magnetoacoustic signal emitted by magnetic particles facilitates accurate mapping of the size and location information of magnetic particles enveloping breast tumors, as well as distinguishing between benign and malignant tumors.
Simulation Research on Breast Tumor Model Based on Magnetoacoustic Concentration Tomography of Magnetic Nanoparticles with Magnetic Induction
2023-12-29
PIER C
Vol. 139, 187-195, 2024
download: 269
Gain Enhanced 26 GHz Antenna for 5G Communication Technology
Eko Setijadi , Prasetiyono Hari Mukti and Wolfgang Bosch
Wireless technology, a longstanding focus for researchers, has evolved into an exciting telecommunications topic over several decades. The most recent iteration, Fifth Generation (5G), has been introduced at high frequencies, commonly called millimeter waves. An integral component supporting wireless communication is the antenna. This report details the design of a microstrip antenna operating at a frequency of 26 GHz. The antenna is configured as a rectangular patch microstrip, utilizing coupled slot feeding, organized as an array, and implementing a ring as the gain enhancement technique. The designed antenna undergoes observation for both single-element and 1x2 arrays, both with and without rings. A thorough analysis encompasses gain, bandwidth, return loss, and radiation pattern. The antenna design, developed at a frequency of 26 GHz, demonstrates a substantial gain increase of up to 10 dB and 14 dB in the single-element and 1×2 array configurations achieved by adding a ring. The designed antenna surpasses the previous works' gain of about 3 dB more.
Gain Enhanced 26 GHz Antenna for 5G Communication Technology
2023-12-24
PIER C
Vol. 139, 175-185, 2024
download: 422
A Novel Pentagonal-Shaped Monopole Antenna with a CSRR Metamaterial Loaded Defected Ground for UWB Applications
Chahrazad Bensid , Mohamed Lamine Bouknia , Djamel Sayad , Issa Tamer Elfergani , Hanane Bendjedi , Rami Zegadi , Jonathan Rodriguez , Atul Varshney and Chemseddine Zebiri
This article presents a novel compact ultra-wideband (UWB) planar monopole antenna printed on an FR4 substrate. The antenna consists of a pentagonal radiating element and incorporates loading metamaterial complementary split ring resonator (CSRR) on the ground plane to optimize impedance matching for UWB operation. The overall dimensions of the designed antenna are 17.75×20 mm2. The proposed compact UWB antenna exhibits an operating bandwidth from 3.01 to 12.41 GHz with a -10 dB return loss, and a fractional bandwidth (FBW) of approximately 123%. Additionally, the proposed antenna exhibits a stable radiation pattern with a peak gain of 6.3 dB and a peak radiation efficiency of 98.3%. To validate the simulation results, a prototype has been fabricated and measured, which shows good coherence with the simulation results. In addition, the proposed design is compared with leading antennas for similar applications to demonstrate the suitability of its concept. Moreover, an equivalent circuit model of the CSRR metamaterial cell is developed and validated using ADS software.
A Novel Pentagonal-shaped Monopole Antenna with a CSRR Metamaterial Loaded Defected Ground for UWB Applications
2023-12-24
PIER C
Vol. 139, 167-174, 2024
download: 221
Laser-Based Estimation of the Diffusion Coefficient Profile for the Karman Turbulence Spectrum in Heated Wind Tunnel Jets Using Genetic Algorithm Computation
Jacques Bernard Tissibe , Noé Richard Makon , Maurice Lamara , Elisabeth Ngo Nyobe and Elkana Pemha
Turbulence is a longstanding problem in fluid mechanics for which experimentation remains unavoidable. In contrast to conventional experimental techniques that inevitably require the introduction of probes into the flow, a very convenient technique would be one in which there is no contact between the measuring sensors and the flow. The laser-based diagnostic technique reported in this work is described as an estimation of a large number of parameters defining the diffusion coefficient profile in the heated turbulent wind tunnel jet, which is required in the formula of the Karman turbulence spectrum for the jet under study. For this purpose, some required experiments in the jet are carried out. A laser beam is then sent perpendicular to the jet exhaust, and measurements of the probabilities of the position of the laser beam's impact on a photocell placed outside the jet are performed. Using the Markovian model, the same probabilities are calculated numerically. For these numerical results to agree with the experimental results, a numerical optimal-control strategy is applied. Due to the large number of unknown parameters searched, a genetic algorithm (GA) computation is performed. A good agreement observed between the GA results and those derived from the previously published cold-wire-anemometer data, combined with the use of the Dale-Gladstone law, proves the validity and accuracy of the laser-based genetic measurement technique.
Laser-based Estimation of the Diffusion Coefficient Profile for the Karman Turbulence Spectrum in Heated Wind Tunnel Jets Using Genetic Algorithm Computation
2023-12-24
PIER C
Vol. 139, 159-166, 2024
download: 285
Conformal Flexible Omnidirectional Rectenna Array Designed for Application in IoT Smart Water Meters
Ruinan Fan , Junlin Mi , Jianwei Jing , Liping Yan and Changjun Liu
In this manuscript, we propose a conformable and flexible meander dipole rectenna array for omnidirectionally harvesting ambient RF power for application in Internet of Things (IoT) water meters. The array unit consists of an antenna for RF power harvesting and a Schottky diode for converting the harvested RF power into DC power. The impedance between the antenna and diode is directly conjugated and matched using a meander structure and coupling loop. Traditional matching networks introduce additional losses, while direct conjugate matching maximizes power transmission efficiency and reduces energy losses. The elimination of the matching network simplifies the design of the rectenna, reducing the number of components and the overall size and weight. The rectenna unit is suitable for low-power ambient energy harvesting and operates at 2.45 GHz. The measured RF to DC conversion efficiency of the rectenna unit reaches 50% at 0 dBm. The rectenna array is formed by connecting eight antenna units in parallel, and units are affixed to the four surfaces of the water meter case to achieve omnidirectional RF environmental power harvesting. The output DC power of the array can be up to 1.3 mW at 100 μW/cm2 received power density. An energy management circuit (BQ25504) is designed to efficiently store, distribute, and manage the harvesting of RF power for powering the IoT water meter. Measured results demonstrated that the proposed rectenna array exhibited excellent adaptability and application potential in IoT scenarios.
Conformal Flexible Omnidirectional Rectenna Array Designed for Application in IoT Smart Water Meters
2023-12-23
PIER C
Vol. 139, 147-158, 2024
download: 256
Four Element EC Slot MIMO Antenna for WLAN, Wi-Fi and 5G Applications
Sachin S. Khade , Dinesh B. Bhoyar , Ketki Kotpalliwar , Chitra V. Bawankar and Manish S. Kimmatkar
The architecture of antenna is with four elements design for 5G, Wi-Max, Wi-Fi and WLAN applications. The operating range of the antenna covers the frequency band from 4.72 GHz to 5.24 GHz. The antenna has dimensions of 46 x 46 x 1.6 mm3 with four elements. The antenna is designed with a planer monopole having two matching stubs connected at the lower end. All the elements of antenna contain E and C shaped slots and two identical stubs providing capacitive effect. The Gain of the designed antennas ranges from 2.23 dB to 2.73 dB for the desired bands. The designed antenna shows suitability for 4.9 GHz WLAN band, 5 GHz and 5.15 GHz Wi-Fi and Wi-Max bands. Also it covers part of the n79 5G band.
Four Element EC Slot MIMO Antenna for WLAN, Wi-Fi and 5G Applications
2023-12-21
PIER C
Vol. 139, 139-146, 2024
download: 150
Evaluation of the Reliability of a Magnetic Levitation System by the Intrusive Stochastic Finite Element Method
Zehor Oudni and Thinhinane Mahmoudi
This work concerns the study of the reliability of a magnetic levitation system. A numerical calculation method based on the introduction of a random variable on the physical property of the materials constituting the levitation system is proposed. The latter is called intrusive stochastic finite element method (ISFEM), and the randomness of physical properties is taken care of, thus modeling in uncertain medium is feasible. The electromagnetic problem is treated with 2D hypotheses for modeling in an uncertain environment. This method was developed in 1991 and used for sensitivity and reliability analysis in the mechanical field; it is extended to the study of applications in linear elasticity and in electromagnetism. The random variable is of Gaussian type. The assessment of the reliability of the levitation system is discussed. The results obtained are compared with those found by the Latin hyper cube method. The intrusive stochastic finite element model provides very conclusive results in a very short time compared to those obtained by Latin hyper cube modeling.
Evaluation of the Reliability of a Magnetic Levitation System by the Intrusive Stochastic Finite Element Method
2023-12-17
PIER C
Vol. 139, 129-137, 2024
download: 219
An X-Band Frequency Beam-Scanning Circularly-Polarized Leaky-Wave Antenna with Low Axial Ratio in All Half-Power Beamwidth Ranges
Dezhuang Zhang , Zhongbao Wang , Zhixia Xu , Hongmei Liu , Mingming Gao and Shao-Jun Fang
A novel frequency beam-scanning circularly-polarized leaky-wave antenna with the axial ratio (AR) of less than 3 dB in all the half-power beamwidth ranges based on an H-shaped slow-wave transmission line is proposed for X-band applications. The proposed circularly-polarized leaky-wave antenna is composed of a novel slow-wave transmission line and two rows of elliptical patch structures, leading to wide AR bandwidth, backward-to-forward beam scanning, and stable gain. To verify the proposed antenna, one prototype with a center frequency of 10 GHz is designed and fabricated. Measured results indicate that the main beam scans from -25° to +28° within the operating frequency variation from 8.7 to 11.5 GHz. The 3-dB AR bandwidth and maximum gain are 27.7% and 10.28 dBic, respectively.
An X-Band Frequency Beam-Scanning Circularly-Polarized Leaky-Wave Antenna with Low Axial Ratio in All Half-Power Beamwidth Ranges
2023-12-16
PIER C
Vol. 139, 119-127, 2024
download: 214
Design and Analysis of Wideband Cross Dipole Antenna with Bent Arms for Base Station Applications
Lakshminarayana Pollayi and Dasari Rama Krishna
This paper presents a wideband dual slant polarized cross dipole antenna used to serve 2G/3G/4G/5G frequency bands. The proposed antenna model consists of two linearly polarized bent cross-dipole antennas, a cross-shaped director, and a metal reflector with walls in an open box manner. Bent dipole arms are etched on PCB to make the element compact. These cross dipoles are fed by hook-shaped wideband baluns. A cross director was placed on top of the cross dipole structure to achieve wideband impedance matching. The linearly polarized dipoles are placed orthogonally to achieve ±45° slant polarization. Two orthogonal polarizations were realized by exciting two input ports separately. A prototype has been fabricated, and measurements are carried out to validate the antenna performance. The measured results show that the antenna is well matched over the wide bandwidth, and the impedance bandwidth is ranging from 617 MHz to 990 MHz for VSWR<2, which is about 48%. The measured isolation between two orthogonal ports of the antenna was observed to be better than 33 dB. The radiation characteristics of the proposed model were stable, and the realized gain is in the range of 8.1±0.5 dBi. The values of the cross-polarization discrimination (XPD) are better than 20 dB at the boresight and 8 dB within ±60° directions. The proposed antenna model has advantages like wide impedance bandwidth, wide pattern bandwidth, stable radiation performance, simple structure, and a small overall size of 350 mm × 350 mm × 100 mm.
Design and Analysis of Wideband Cross Dipole Antenna with Bent Arms for Base Station Applications
2023-12-13
PIER C
Vol. 139, 107-118, 2024
download: 267
Design of Wide Notched-Band Circular Monopole Ultra-Wideband Reconfigurable Antenna Using PIN Diodes Switches
Annu Tiwari , Dinesh Yadav , Purnima Sharma and Manish Varun Yadav
This communication presents the design of a circular monopole ultra-wideband (UWB) reconfigurable antenna with wide notched-band of 1 GHz which ranges from 5 to 6 GHz in UWB. The design involves a circular monopole antenna with embedded three thin slots (two vertical and one horizontal) and one rectangular slot at the top edge. The three p-i-n diodes are inserted in between vertical slots to control the flow of surface current in ON/OFF states. As a result, in all diodes' ON and OFF states, the designed antenna shows switching of its resonance in whole UWB to wide notched band UWB applications. The CST-microwave studio software is used to simulate the structure in time domain. The full modeling of reported reconfigurable antenna that includes reactive effects of the diode is achieved by ADS circuit simulator.
Design of Wide Notched-band Circular Monopole Ultra-wideband Reconfigurable Antenna Using PIN Diodes Switches
2023-12-12
PIER C
Vol. 139, 95-105, 2024
download: 167
Performance Evaluation of Thinning on Multifunctional Array Antennas
Polepalli SaiVinay
The array covers the L-band and S-band range frequencies used for multifunctional applications and operate between 1.61 GHz and 2.492 GHz. The quad frequency antenna resonates at four frequencies 1.176 GHz, 1.575 GHz, 1.6 GHz, and 2.492 GHz, which cover the L-band and S-band frequencies. The configurations of both antennas are layered patches. Performance measurements of the two antenna arrays have been compared, including side lobe level, return loss, and gain. Both the antennas are fabricated using affordable, easily accessible FR4 Epoxy. By implementing thinning for both array antennas, gain values are observed, and good performances are obtained.
Performance Evaluation of Thinning on Multifunctional Array Antennas
2023-12-08
PIER C
Vol. 139, 87-94, 2024
download: 198
Performance Enhancement of High-Gain STDA Antennas with Reflector for 4G LTE and Sub-6 GHz 5G Applications: Design, Measurement, and Analysis
Mohd Wasim , Shelej Khera , Tanvir Islam , Praveen Kumar Malik , Sivaji Asha and Das Sudipta
The paper focuses on the design, measurement, and performance analysis of a high-gain cross-orthogonal series fed two dipole antenna (STDA) arrays with side-wall reflectors. The antenna is specifically designed for 4G Long Term Evolution (LTE) and sub-6 GHz 5G band applications. The designed antenna is capable of operating at multiple frequencies aiming to support 4G LTE and the sub-6 GHz 5G application bands. To improve the radiation characteristics and prevent coupling effects in the presence of side-wall reflectors, parasitic strip pair directors are included in the antenna design. Furthermore, the performance of the designed STDA is evaluated by forming different array configurations, such as 2×1, 2×2, and 2×3 arrays. The various array configurations are proposed to investigate the effect of the projected array arrangements on the radiation pattern, impedance bandwidth, and gain characteristics. The results of the measurements show that the radiation characteristics of the antenna has improved significantly. The proposed antenna operates at six distinct frequencies for S11≤-10 dB. The operating frequencies at 1.8, 2.35, and 2.6 GHz can be utilized for LTE and 3.2, 4.2, and 5.2 GHz can support sub-6 GHz 5G bands. The antenna is characterized by its compact size, measuring around 89 mm × 71 mm, while still achieving high gain of 12.3 dB for single STDA element with parasites and with reflector. These results emphasize the importance of the proposed design, which incorporates parasitic strip pair directors and side-wall reflectors. This design methodology plays a crucial role in enhancing the performance of the prescribed STDA array for both 4G LTE and sub-6 GHz 5G applications.
Performance Enhancement of High-gain STDA Antennas with Reflector for 4G LTE and Sub-6 GHz 5G Applications: Design, Measurement, and Analysis
2023-12-07
PIER C
Vol. 139, 79-86, 2024
download: 203
A Low-Profile, Size-Reduced, High Gain, Circularly Polarized Anti-Jam Global Positioning System Antenna Array
Grant Evans , Jack Nemec , Victor Obi and Sungkyun Lim
A high gain, circularly polarized array antenna is proposed with low profile and compact size using T-shaped top loading, t-matching, and a reflector. Composed of 4 individual elements, the array has a -3-dB impedance bandwidth of 1.39% (1.564-1.586 GHz) and a 3-dB axial ratio beamwidth of 79° (-42°-37°) in measurement. The front-to-side ratio of the total realized gain pattern is 27.1 dB and the front-to-back ratio is 25.5 dB. The peak realized gain is 11.0 dBi in the forward (+z) direction. The proposed antenna is a good candidate for functioning as an anti-jam antenna in global positioning system, helping to block out jamming signals coming from the horizontal (90° and 270°) planes.
A Low-profile, Size-reduced, High Gain, Circularly Polarized Anti-jam Global Positioning System Antenna Array
2023-12-03
PIER C
Vol. 139, 67-77, 2024
download: 213
PMSWG Parameter Identification Method Based on Improved Operator Genetic Algorithm
Zhun Cheng , Chao Zhang and Yang Zhang
Permanent Magnet Synchronous Wind Generator (PMSWG) parameter identification method with improved operator genetic algorithm is proposed for the influence of perturbations caused by mechanical parameter changes on the dynamic performance of motor speed control system. Firstly, current with id=0 and id≠0 are injected into axis d respectively to design the fitness function. Through quantum coding, the genetic algorithm can obtain better population and fitness in the early stage, and find better solutions in the search space. At the same time, the cross method of two random numbers is used to make the cross variable not restricted in a range, which enhances the global search ability. Finally, the update strategy of hybrid mutation composed of Gaussian mutation and Cauchy mutation is introduced to ensure the global search ability of the algorithm, and the accuracy of the optimization results is improved. Experiments show that the proposed method avoids local optimization and achieves global optimization, which can further improve the convergence speed and identification accuracy of the algorithm.
PMSWG Parameter Identification Method Based on Improved Operator Genetic Algorithm
2023-12-03
PIER C
Vol. 139, 59-66, 2024
download: 272
Frequency Diversity Arc Array with Angular Broadening Null Steering for Sidelobe Suppression
Ying Tian , Wei Xu , Pingping Huang , Weixian Tan and Yaolong Qi
The structure of the frequency diversity arc array (FDAA) is a circular arc, which can achieve fast scanning in all directions and large viewing angles. By selecting the appropriate array elements for FDAA to form an effective working array and designing the symmetrical logarithmic frequency offset, a more aggregated point-like beam pattern is obtained. However, due to the structural characteristics of FDAA, the anti-density weighting phenomenon is generated, which limits the application of FDAA in radar system for target recognition and tracking. In order to solve the problem of high sidelobe of FDAA caused by inverse density weighting, a method of FDAA with angle widening null guidance for sidelobe suppression is proposed in this paper. The linear constraint minimum variance (LCMV) criterion is used to set zero points at a fixed position in the direction of interference, so that the interference is in a null with a certain width. Through Matlab simulation, it is verified that this method has a certain effect on suppressing FDAA sidelobe interference.
Frequency Diversity Arc Array with Angular Broadening Null Steering for Sidelobe Suppression
2023-12-02
PIER C
Vol. 139, 45-57, 2024
download: 210
A Combinatorial Approach to Quantitative Microwave Imaging for Breast Tumour Profiling Using SVBIM and SpaRSA
Ria Benny , Thathamkulam A. Anjit , Philip Cherian and Palayyan Mythili
A combinatorial quantitative reconstruction method employing Subspace-based Virtual Born Iteration Method (SVBIM) along with a greedy compressive sensing algorithm, Sparse Reconstruction by Separable Approximation (SpaRSA) to solve the ill-posed inverse problem in microwave imaging is proposed in this paper. SVBIM makes use of the contribution of the variational induced current to arrive at a better estimate of the permittivity profile in each iteration. SpaRSA operates in the sparse domain and reduces the computational overload, thereby guiding the inverse problem towards a faster global optimum solution. The merger of these two algorithms helps to reconstruct breast profiles having high-permittivity tumour inclusions (ε = 60) with reduced error. The proposed reconstruction method is capable of extracting the salient information regarding tissue differentiation (permittivity and conductivity) and dielectric distribution of various tumour and fibroglandular inclusions within the object, dimensions, resolution, size, shape and coordinate localization of inclusions. In comparison to various methods reported in literature, the results obtained using the proposed method are highly encouraging. In the presence of 30 dB noise, the above-said imaging technique produces a significantly reduced permittivity error value of 0.47 in the reconstruction of tumour inclusions as against 0.85 and 0.71 in the case of TV norm and Re-weighted Basis Pursuit methods respectively. The experimental validation is carried out using a phantom having three inclusions of sizes 10 mm, 6 mm, and 3 mm. The inclusions have been localized successfully with errors of 0.089, 0.133, and 0.21, respectively.
A Combinatorial Approach to Quantitative Microwave Imaging for Breast Tumour Profiling Using SVBIM and SpaRSA
2023-12-01
PIER C
Vol. 139, 31-43, 2024
download: 279
A Small Size Wideband m -Shaped Polygonal Slot Antenna for X-Band Satellite Applications
Mostafa Mahmoud Rabie , Mohamed S. El-Gendy , Angie Reda El Damak , Fawzy Ibrahim and Hadia El-Hennawy
This paper presents a small size M-shaped polygonal slot antenna for X-band satellite telemetry and Synthetic Aperture Radar (SAR) applications. The proposed antenna has been designed on a Roger RT-Duroid 5880 substrate. The reflection coefficient |S11| of the proposed antenna covers the whole X-band from 6.63 GHz to 12.566 GHz. The proposed antenna is circularly polarized with axial ratio (AR) bandwidth that extends from 7.76 GHz to 8.58 GHz. The proposed antenna provides a simultaneous dual circular polarizations (RHCP and LHCP). The gain of the proposed antenna varies between 6.6 dBi and 9.4 dBi. The proposed antenna realizes an efficiency of 92%. The overall size of the proposed antenna is 17 x 16 x 0.508 mm3 (0.56λ0 x 0.53λ0 x 0.016λ0). Therefore, it is suitable to be employed in satellite telemetry application from 7.9 GHz to 8.4 GHz especially for CubeSats that have limited surface area. Apart from that, this antenna finds its applications in SAR on small satellites from 9 GHz to 10 GHz, military, and RFID tag (tracking-equipment). It has been observed that the measurement results match the simulated ones. The proposed antenna design can be practically employed for the previously mentioned applications.
A Small Size Wideband M-shaped Polygonal Slot Antenna for X-band Satellite Applications
2023-11-24
PIER C
Vol. 139, 21-29, 2024
download: 243
The Direct Torque Control of Brushless DC Motor Based on Sliding Mode Variable Structure
Gai Liu , Yiran Wu and Qingbo Shao
Aiming at the problem of slow response speed and poor anti-interference ability using the traditional PI control in the direct torque control strategy of brushless DC motor (BLDCM), the direct torque control (DTC) of the BLDCM based on the sliding mode change (SMC) structure is proposed. In the BLDCM DTC system under the new flux linkage set mode, the traditional PI control is replaced by the improved SMC control to realize the new torque given mode and realize the DTC of the BLDCM. Firstly, the integral sliding mode surface is used instead of the traditional linear sliding mode surface to optimize the continuity of the SMC structure and reduce the high-frequency perturbation caused by the differential phase, thus reducing the smooth torque and system steady-state error. Secondly, the system is simulated by MATLAB/SIMULINK; the given torque of the improved SMC is the most stable; and the speed response curve is smoother. Finally, the construction of the BLDCM test platform is completed. The experimental results show that in the BLDCM DTC control system of the new flux linkage set mode, based on the improved SMC, the system has faster response speed and stronger anti-interference, and shows stronger dynamic and static performance.
The Direct Torque Control of Brushless DC Motor Based on Sliding Mode Variable Structure
2023-11-23
PIER C
Vol. 139, 11-20, 2024
download: 293
Design of Permanent Magnet Synchronous Wind Power Control System
Huajun Ran , Wenjin Wei and Yue Gao
To tackle the slow response and insufficient interference resistance exhibited by permanent magnet synchronous motors (PMSMs) under traditional field-oriented control (FOC). This paper proposes an integral sliding mode controller (SMC) to improve the speed loop, and adaptive law is also developed using a nonlinear smooth function to eliminate the chattering phenomenon of the sliding mode control. Meanwhile, an extended state observer is designed to estimate and compensate for the disturbances caused by wind speed uncertainty and the system's internal disturbances. Then, model predictive control (MPC) is employed for the current loop to eliminate the overshoot and achieve fast tracking. Finally, a step-by-step model reference adaptive scheme (MRAS) is proposed to identify the parameters and eliminate the internal disturbances in addressing parameter perturbation in the motor during operation. The simulation results demonstrate that the enhanced system exhibits almost no overshoot, superior steady-state performance, quick dynamic response, and resistance to both internal and external disturbances, ultimately validating the efficacy of the approach.
Design of Permanent Magnet Synchronous Wind Power Control System
2023-11-19
PIER C
Vol. 139, 1-10, 2024
download: 303
Design of True Time Delay Line Based Octal Transmit Receive Module for Wideband Phased Arrays
Kilari Sreenivasulu , Kamla Prasan Ray , Alagarswami Vengadarajan and Dharmavarapu Srinivasa Rao
Wideband phased arrays for Electronic Warfare (EW) applications utilize narrowband phase shifters in a switched configuration to cover a multi-octave bandwidth in split bands. Wideband True Time Delay (TTD) line circuits are the best candidates to replace narrowband phase shifters in such systems, covering the complete operating bandwidth in a single step. The Transmit Receive Module (TRM) is a critical component of any phased array system. A novel design of a TTD line-based Octal Transmit Receive Module (OTRM) for a 32-element EW phased array over a frequency range of 1-6 GHz is presented in this paper. The OTRM is designed on a single multi-layer PCB by integrating eight transmit-receive (TR) channels, associated controllers, and power conditioning circuitry in a compact size and weight of 800 grams. The paper addresses challenges associated in design of TR channels to fit within the inter-element spacing of 14 mm and to achieve isolation of ≥40 dB between channels. The designed OTRM tunes time delay up to 508 ps maximum with a step of 2 ps by using a single TTD line circuit for ±45° scan coverage. The OTRM has demonstrated its potential capability for use in wideband Radar, EW, and Communication system applications. Efficient thermal management of the OTRM is achieved by introducing Copper coins below the final power amplifiers and a liquid cold plate to dissipate a heat load of 32 watts per TR channel. The proposed OTRM delivers transmit power of 8 watts (CW), receive gain of 25 dB, and a noise figure of 6 dB per TR channel with an overall efficiency of 19% (min) over a 5 GHz bandwidth. RF path analysis of the TR channel in transmit and receive paths is carried out using the Systemvue software tool. To verify the design of the OTRM over different time delay and attenuator states, measurements are conducted using a Vector Network Analyzer (VNA).
Design of True Time Delay Line Based Octal Transmit Receive Module for Wideband Phased Arrays