Miracle-dz/UniFAR-FTUs huggingface dataset:
A Novel Blind Adaptive Beamformer with Robustness against Mutual Coupling and Miscalibration Effects

Beamforming techniques utilized either at the transmitter or the receiver terminals have achieved superior quality-of-service performances from both the multi-antenna wireless communications systems, communications intelligence and radar target detection perspectives. Despite the overwhelming advantages in ideal operating conditions, beamforming approaches have been shown to face substantial performance degradations due to unknown mutual coupling effects and miscalibrated array elements. As a promising solution, blind beamformers have been proposed as a class of receiver beamformers that do not require a reference signal to operate. In this paper, a novel gradient-based blind beamformer is introduced with the aim of mitigating the deteriorating effects of unknown mutual coupling or miscalibration effects. The proposed approach is shown to find the optimal weights in different antenna array configurations in the presence of several unknown imperfections (e.g., mutual coupling effects, miscalibration effects due to gain and phase variations, inaccurate antenna positions). By providing numerical results related to the proposed algorithm for different array configurations, and bench-marking with the other existing approaches, the proposed scheme has been shown to achieve superior performance in many aspects. Additionally, a measurement-based analysis has been included with validation purposes.
EM-based Building Material Parameter Estimation with Wideband Free Space Measurement Method

Recent computer technology has made significant progress, and various radio propagation simulation techniques are utilized for the performance evaluation and design of wireless networks. In the simulation, constructing the correct communication environment model is essential for the reliability of the simulation. In this paper, we developed a measurement system based on the free space method to estimate the material parameters of the environment objects. The permittivity, the conductivities, and the thickness of the material are jointly estimated by a maximum likelihood (ML) based algorithm. The experiment was conducted in the 33 GHz band, and the material parameters of a door glass were estimated. The estimation result entirely matched the measurement, and it showed that our proposal is effective in obtaining equivalent material parameters for radio propagation simulation. Further experiments with various building materials and their utilization for radio propagation simulations are future works.
Customized Rectangular Microstrip Patch Antenna for Enhanced Gain to operate at 7.5 GHz

The most inherent drawback of patch antenna is the reduction in gain. It happens due to flow of surface currents and low radiation efficiency. This paper aids in examination of various gain improvement techniques and the design of rectangular patch modified in a systematic way to obtain the desired gain by using rectangular and circular slots. The antenna designs are developed at 7. 5GHz which is applicable for satellite communications. The designs are developed in Ansys HFSS software and the various simulation results are obtained. From the simulation results, the various parameters are compared for the developed six designs and observation proves hybrid combination of slot structures as the well choice for practical implementation.
Sizing Large Numbers of Grid-connected Microgrids Based on Bayesian Optimization

Nowadays, in order to solve the uncertainty of the renewable energy resources, microgrid has been widely installed. However, when large numbers of microgrids are connected to utility grid, how to optimally operate this grid-connected microgrids, and how to size the components capacity to ensure the security of the utility grid is a basic question. Thus, authors in this paper present a sizing method based on Bayesian optimization for large numbers of grid-connected microgrids. First, a decentralized operation method is deployed to operate the large numbers of grid-connected microgrids, in which, the microgrid exchanged energy with utility grid are decision variables. Second, a four microgrids grid-connected model is established. Then, Bayesian optimization is adopted to size the components capacity, due to its excellent performance in hyper-parameter optimization area. The results demonstrate that the Bayesian optimization has effective ability to search planning values, and also provide a new idea to solve the combinational optimization problem.
Frequency Model for EMI Study of Three-Phase Grid Connected Photovoltaic Inverter on Both DC and AC Sides

This paper presents an EMC model in the frequency domain for grid connected three-phase photovoltaic inverters using the conventional Boost-Inverter topology. The aim is to estimate the EMC noises on both DC and AC sides, in order to design for instance EMI filters, or for any sensitivity analysis or optimization process. The model is developed and validated on an experimental prototype setup. The results are discussed, focusing on the contribution of each converter to the noise produced, both on the DC and AC sides by considering the impedance path of noises.
Dual-Band, Slant-Polarized MIMO Antenna Set for Vehicular Communication

Slant-polarized Multi Input Multi Output (MIMO) antennas are able to improve the performance of mobile communication systems in terms of channel capacity. Specifically, the implementation of MIMO configurations for automotive applications requires the consideration of high gain, wideband, low-profile and affordable antennas in the communication link. In this work, design, simulation and measurement of a new dual-band slant-polarized MIMO antenna with HPBW (Half Power Beam Width) of around 900 are presented. Then, four replicas of the proposed antenna set are placed at four different poles (North, South, West and East) to cover 3600 around the vehicle in an omni-directional pattern. In a real-world scenario, the proper antenna set is selected to communicate with the intended user. Each slant MIMO antenna set consists of two inclined (450) low band (LB: 700 to 900 MHz) and two inclined high band (HB: 1.7 to 2.7 GHz) log-periodic antennas. The measured gain of LB and HB antennas are 7 dBi and 8 dBi, respectively. Strong correlation between simulation and measurement results confirms the accuracy of the design and simulation procedures of the proposed antenna system, obtained using a genetic optimization algorithm. The fabricated antenna was also measured in the field for industrial applications.
Multi–Objective Optimisation of Metamaterial Antenna

Passive manipulation of radiation is key to many modern technologies for sensing and communication. While many techniques exist to design electromagnetic systems that perform a single desired function, the design of systems which are multi–functional remains challenging. We have developed a versatile semi–analytic framework for designing multi–functional metamaterials to shape antenna radiation. To demonstrate the versatility of this method we design two devices: one which re– shapes the radiation pattern of an emitter while also enhancing the efficiency, and one which beams radiation into different directions depending upon the polarisation of a driven element.
Direction of Arrival Estimation on Sparse Arrays Using Compressive Sensing and MUSIC

Now-a-days radar target detection is a safety critical system in automotive applications involving autonomous driving. The security and trustworthiness of such systems can be improved using a sparse interleaved array. In this paper, we present a new method for target detection for this sparse array, which combines the root-MUSIC algorithm with orthogonal matching pursuit (OMP) to estimate the azimuth angle and recovers the signal. It compensates the major drawbacks of compressed sensing, in which the choice of underlying grid for azimuth angles affects the optimality of the solution. The elevation angles is then estimated from the approximated signal using root-MUSIC. Based on experimental results with 77 GHz MIMO system, we may achieve a high precision in angle estimation without aliasing as well as increased dynamic range of 3dB in comparison to conventional methods.
Study on Load Rejection Overvoltage of PMSG Wind Power Transmission system

Overvoltage is generated when load rejection occurs in transmission lines. The characteristics of load rejection overvoltage process for wind power transmission system are different from that of traditional AC system. In this paper the characteristics and mechanism of load rejection overvoltage for wind power transmission system consists of permanent magnet synchronous generator (PMSG) is studied. Simulation were carried out based on typical system. The analysis of mechanism is verified by simulation. Overvoltage limitation effect of limitation measures were also studied.
FPGA Implementation of Range Safety Panel for Flight Termination System using LabVIEW

This paper demonstrates the design and implementation of a field programmable gate array (FPGA) based range safety panel (RSP) for flight termination system(FTS). In flight testing center, FTS is used for transmitting command to the flight vehicle and destroy it if it is out of designated path. Flight safety officer observes the behavior of the flight vehicle and remotely controls the FTS using RSP. NI SbRIO - 9607 compact rio controller along with Xilinx FPGA is used for RSP realisation. LabVIEW programming language is used to implement the system in real time within designated time delay acceptable for decision making process by range safety officer. GUI is designed For configuration and monitoring of RSP Performance in real time in LabVIEW. The real time performance of the system is validated against its expected performance using various test cases in real time local and remote operations.
A Low-Profile Cellular Antenna Module for Vehicular Applications

Since the number of wireless systems integrated into vehicles is increasing, the design of radiating elements and their positioning on the vehicle has become challenging. For this reason, there is a need to find new positions on a vehicle for the antenna elements, different from the typical location on the car roof (e.g. under the plastic shark-fin cover). In this paper, a novel system of 4 low-profile radiating elements for 4x4 MIMO LTE/5G cellular applications is presented to be integrated into a vehicle, for example inside the rear spoiler or under the dashboard.
Enhanced VANET Performance by Stable Cluster Head Selection Using Novel Stack of Algorithms

The use of VANET turns the roadway into a communal space, enhancing safety and facilitating data sharing among drivers. Data from each automobile is transmitted to the cluster head (CH) via a cluster. There are two main aspects that impact the effectiveness of a VANET network: the optimal number of the vehicle groups and the choice of the control node for stability. In this paper, we model the VANET as a hypergraph network and construct a state-of the-art modularity-based hypergraph clustering formulation by maximising tensor traces and using the modularity matrix as a feed to determine the optimal number of clusters. Automobiles were selected from each group based on how fast they were compared to others in the group, how trustworthy they were deemed by the group as a whole, how long their links lasted, and how well connected they were. All parameters are first transformed to eigenvalues, then a single CH is chosen. By adopting a fuzzy decision-making technique based on three factors, the optimal CH is selected for all vehicles in that cluster. Furthermore, the proposed method for selecting the reliable CH to improve throughput has been validated and significantly improved by comparing it to the other existing techniques.
Radiation efficiency estimation of lossy geodesic lens antennas based on a ray-tracing technique

Here, we propose a generalized ray-tracing (RT) model to accurately compute the radiation patterns and radiation efficiency of lossy non-rotationally symmetric geodesic lens antennas. The RT model uses geometrical optics to obtain the ray paths from the source to the aperture, ray tube theory to calculate the field amplitude distribution, and Kirchhoff’s diffraction formula to compute the radiation pattern. Losses in geodesic lenses are mainly produced by the finite conductivity and roughness of the metallic plates. These losses are added to the calculation of the radiation pattern to estimate the radiation efficiency of the antenna. To demonstrate the accuracy of the proposed RT model, a geodesic half-Maxwell fish-eye lens is designed. Radiation patterns, scan losses, and radiation efficiency are calculated. These results agree well with those computed by full-wave simulations.
Multi-time Scale Synchronization and Adaptive Power Sharing Control Scheme for Grid Forming Inverters in a Power Electronics Dominated Grid

This paper presents a hierarchical multi-time scale synchronization and adaptive power sharing scheme for fleet of grid-forming (GFM) inverters as backbone of upcoming power electronics dominated grids (PEDG). GFM inverters should be capable of dynamically and seamlessly synchronizing as well as islanding from the network, when demanded. Furthermore, the power sharing coordination between these interconnected GFM inverters needs to be dynamically adjusted, in response to the anticipated system reconfigurations. The seamless integration of GFM inverters and the real-time adjustment of droop gains is vital to address the adverse dynamic interactions observed during such PEDG reconfigurations. This paper proposes a control scheme that enables seamless synchronization of GFM inverters and ensures stability in a PEDG. Moreover, a coordination controller (CC) is proposed to dynamically adjust the droop gains for all interconnected GFM inverters based on their generation capacities; thereby maintaining system resiliency and reliable power sharing against load variations. Simulation results obtained from various case studies emulated in MATLAB Simulink environment indicate the controller's ability to operate efficiently in a dynamically reconfiguring PEDG network.
A Reconfigurable LCC-P/S Compensated Three-Phase Wireless Charging Topology with Constant Current and Constant Voltage Output

A practical wireless charging system should be capable of both constant current (CC) charging and constant voltage (CV) charging for batteries. As a solution, reconfigurable topologies have been widely studied for single-phase systems. This paper proposes a novel reconfigurable topology for three-phase wireless charging systems without extra capacitors or inductors that previous single-phase designs usually have. In the proposed topology, an LCC compensation network of the transmitter and the parallel (P) / series (S) capacitors of the reconfigurable receiver consist of the LCC-P/S topology for CC charging or CV charging respectively. The change of topology from LCC-P to LCC-S is realized by two 3-pole double-throw (3PDT) power relays. Relay operations have been optimized to minimize arc flashes to protect the relay contacts. A 1.8 kW three-phase unipolar-coil-based experimental prototype is built. The experimental results have verified CC and CV characteristics. Output current and voltage variances are less than 2% and 1.3% respectively. The maximum efficiency is 94.6% and 93.5% in CC mode and CV mode respectively.
EEG Based Brain Computer Interface System for Decoding Covert Speech using Deep Neural Networks

The study aims to learn deep features from EEG signals corresponding to the imagery of words to design a BCI(Brain computer interface) system based on human thoughts. Topological plots of time-averaged EEG signals across all the trials corresponding to the imagery of a particular word are fed as input to the designed deep neural network algorithm. Designed deep learning architecture has an amalgamation of the Two-dimensional convolutional neural network and LSTM that takes the assistance of the capabilities and assets of both neural network architectures. The proposed neural network architecture achieves admirable accuracy in identifying imagined words from the EEG-based Kara one dataset. The accuracy of the designed CNN-LSTM model with topological plots as input features was 20-25% more than chance level accuracy and comparable to the state of arts.
An Optimized Method for Selecting Rational Polynomial Coefficients Based on Multicollinearity Analysis

In the geometric processing of high-resolution satellite imagery,the general rational function model(RFM) consists of 78 rational polynomial coefficients(RPCs),and the correlation between these coefficients will result in difficulties and accuracy degradation in solving the RPC.The rigorous error equations for solving the RPCs are derived,and an optimized method of selecting the RPCs by analyzing the multicollinearity between column vectors of the design matrix is proposed.A SPOT-5 HRG image in level 1A is selected and used.The empirical results have shown that selecting 20 to 30 RPCs could effectively eliminate the correlation between the coefficients,remove the oscillation in approximating the terrain by using the RFM,and obviously raise the solution accuracy of the RPCs and geometric processing accuracy based on the RFM with less ground control points(GCPs) available.When the GCPs are sufficient,the selected RPCs could acquire a consistent geometric accuracy in approximating the terrain with the 78 RPCs solved by the traditional least-squares method.
Miniaturized Broadband dual-polarized Dielectric Resonator Antenna Using Characteristic Modes

This paper presents a compact and broadband dielectric resonator antenna (DRA) with dual polarization radiation. To achieve a compact size the high permittivity technique is used which results in a narrow bandwidth. In an effort to improve the resultant bandwidth of the DRA, the characteristic mode analysis (CMA) is used. First, a conventional rectangular DRA is analyzed by CMA, as a result, two pairs of degenerate modes resonating at two different frequencies (0.41GHz and 0.61 GHz) are selected for having dual polarization performances. Based on that and to adjust the selected modes so that to merge them for broadband radiation, the DRA’s shape has been changed to a cross-notch shape with a size of 0. 2λ × 0. 2λ. The simulation results show a bandwidth of 20.6%, a gain of 5dBi, and high isolation of more than 50 dB. Having these features, the proposed antenna can be of great use in massive MIMO antenna applications in the low band (<1GHz).
Carrier Based Pulse Width Modulation for Low Distortion Sinewave Generation using Hybrid Harmonics Elimination Method

This paper introduces a hybrid harmonic elimination carrier-based pulse width modulation (HECBPWM) method for sinewave generation. The harmonic elimination algorithm is validated via an FPGA based digital controller and a three-phase multilevel inverter experimental prototype. The harmonic elimination algorithm generates the inverter PWM signals to eliminate unwanted harmonics of the output voltage waveform. The HECBPWM utilize continues duty cycle trajectories as a function of the desired modulation index for the PWM generation. The duty cycle functions reduce computing power requirements by using asynchronous calculation procedure and pre- calculated coefficients. The adaptation of algorithm for full-bridge single phase inverter and a three-level NPC single-phase inverter is detailed and demonstrated experimentally. The experimental prototype operation with an inductive load is shown along with the cancelation of multiple unwanted harmonics at the output voltage.
Near-Field Shaped Transmitarray Antennas: Synthesis and Impact of Phase Quantization

In this work, a procedure based on the Intersection Approach, is proposed to synthesize the near-field pattern of transmitarray antennas. First, the model for the computation of the amplitude and phase of the electric field in the near-field region is described and validated by comparison with full-wave simulations. Next, the proposed phase-only synthesis algorithm is detailed. Using fast Fourier transforms, it iteratively seeks for a feasible aperture phase profile that can fit near-field pattern constraints. The procedure is applied to synthesize a transmitarray generating a near-field shaped pattern on a plane parallel to the aperture. The impact of a uniform phase quantization on the near-field pattern and amplitude is analysed to provide design guidelines.
A Bulb Shaped ACS Fed Triband MIMO Antenna for ISM/LTE/WLAN/Wi-Fi Applications

In this article bulb shaped antenna is designed with ACS feeding technique. The single element with the dimensions of 23 × 11 × 1.6 mm3 fabricated on FR4. The antenna elements are organized orthogonally with 48 × 48 × 1.6 mm3 dimensions for further examination. This MIMO design achieved an operating triband operating frequency of 2.22GHz-2.41GHz,3.48GHz-3.80GHz and 4.96GHz-6.24GHz along with a peak gain of 4.5dB and efficiency of 98%. By using 3D EM tool antenna design and analysis are carried. This design strategy resolved coherence within signals with isolation of less than -20dB. ISM/LTE/WLAN/Wi-Fi are the applications for the proposed bulb shaped MIMO design with acceptable diversity parameters like ECC, DG, MEG, TARC and CCL.
Design and Simulation of a Novel Cell Interaction Based Square Calculator in Quantum-Dot Cellular Automata

In comparison to complementary metal oxide semiconductor (CMOS), quantum-dot cellular automata (QCA) is an efficient nano-scale method for constructing circuits. Innovative digital automation uses relatively low power and is constantly working to boost density. A square calculator is a crucial element in many different digital circuits. In this paper a highly effective and simpler two-bits and four- bits square calculator is created using the QCADesigner modelling environment. The proposed structure of 2-bits square calculator contains only 32 cells (50% less compared to the existing work) and occupied only 0. 03μm2 area. It has an area usage of 34.56% and the latency of the circuit is 0.5-clock cycles. The proposed 4-bits square calculator contains a total cell count of 370 cells (35% less than the existing work) and it occupies an area of 0.67 μm2 with an area utilization of 17.89% and a latency of 1.25-clock cycles. The simulation findings showed that the proposed design is very efficient in terms of cell count, area and delay.
Atomic Scale Analysis of Water Motion Behavior in Three-element Mixed Insulation Oil Under Electric Field Stress

The motion behaviors of water in three-element mixed insulation oil (T-EMIO) were studied using mineral oil (MO) as reference by molecular simulation method. By analyzing the motion behavior, motion trajectory and interaction of water and insulating oil on atomic scale, the differences of motion behavior of water in different insulating oils were revealed. When the applied electrical field does not exist, H atom in water can form hydrogen bond with oxygen atoms in T-EMIO, resulting in strong interaction between water and T-EMIO. However, MO does not contain oxygen atoms and the Hydrogen atom s in MO cannot form hydrogen bonds with the oxygen atoms in water. In addition, the free volume (FV) fraction MO is bigger than T-EMIO. In this case, the mobility of water in MO is much greater than in T-EMIO. When the applied electrical field is present and enhances step by step, the interaction between water and T-EMIO decreases and the FV fraction of water in T-EMIO increases gradually. The interaction between water and MO becomes stronger and the FV fraction of water in MO is basically unchanged. Therefore, the motion capacity of water in the two insulating oils is basically the same under electrical field. This article provides professional support for the fault diagnosis and application of T-EMIO.