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Articles 6181 - 6210 of 7209
Full-Text Articles in Computer Engineering
Identifying A Computer Forensics Expert: A Study To Measure The Characteristics Of Forensic Computer Examiners, Gregory H. Carlton, Reginald Worthley
Identifying A Computer Forensics Expert: A Study To Measure The Characteristics Of Forensic Computer Examiners, Gregory H. Carlton, Reginald Worthley
Journal of Digital Forensics, Security and Law
The usage of digital evidence from electronic devices has been rapidly expanding within litigation, and along with this increased usage, the reliance upon forensic computer examiners to acquire, analyze, and report upon this evidence is also rapidly growing. This growing demand for forensic computer examiners raises questions concerning the selection of individuals qualified to perform this work. While courts have mechanisms for qualifying witnesses that provide testimony based on scientific data, such as digital data, the qualifying criteria covers a wide variety of characteristics including, education, experience, training, professional certifications, or other special skills. In this study, we compare task …
Table Of Contents
Journal of Digital Forensics, Security and Law
No abstract provided.
Measurement And Modeling Of Infrared Nonlinear Absorption Coefficients And Laser-Induced Damage Thresholds In Ge And Gasb, T. J. Wagner, M. A. Bohn, Ronald A. Coutu Jr., L. P. Gonzalez, J. M. Murray, K. L. Schepler, S. Guha
Measurement And Modeling Of Infrared Nonlinear Absorption Coefficients And Laser-Induced Damage Thresholds In Ge And Gasb, T. J. Wagner, M. A. Bohn, Ronald A. Coutu Jr., L. P. Gonzalez, J. M. Murray, K. L. Schepler, S. Guha
Electrical and Computer Engineering Faculty Research and Publications
Using a simultaneous fitting technique to extract nonlinear absorption coefficients from data at two pulse widths, we measure two-photon and free-carrier absorption coefficients for Ge and GaSb at 2.05 and 2.5 μm for the first time, to our knowledge. Results agreed well with published theory. Single-shot damage thresholds were also measured at 2.5 μm and agreed well with modeled thresholds using experimentally determined parameters including nonlinear absorption coefficients and temperature dependent linear absorption. The damage threshold for a single-layer Al2O3 anti-reflective coating on Ge was 55% or 35% lower than the uncoated threshold for picosecond or nanosecond …
Information Theoretic Approach For Assessing Image Fidelity In Photon-Counting Arrays, Srikanth R. Narravula, Majeed M. Hayat, Bahram Javidi
Information Theoretic Approach For Assessing Image Fidelity In Photon-Counting Arrays, Srikanth R. Narravula, Majeed M. Hayat, Bahram Javidi
Electrical and Computer Engineering Faculty Research and Publications
The method of photon-counting integral imaging has been introduced recently for three-dimensional object sensing, visualization, recognition and classification of scenes under photon-starved conditions. This paper presents an information-theoretic model for the photon-counting imaging (PCI) method, thereby providing a rigorous foundation for the merits of PCI in terms of image fidelity. This, in turn, can facilitate our understanding of the demonstrated success of photon-counting integral imaging in compressive imaging and classification. The mutual information between the source and photon-counted images is derived in a Markov random field setting and normalized by the source-image’s entropy, yielding a fidelity metric that is between …
A New Multi-Tier Adaptive Military Manet Security Protocol Using Hybrid Cryptography And Signcryption, Atti̇la A. Yavuz, Fati̇h Alagöz, Emi̇n Anarim
A New Multi-Tier Adaptive Military Manet Security Protocol Using Hybrid Cryptography And Signcryption, Atti̇la A. Yavuz, Fati̇h Alagöz, Emi̇n Anarim
Turkish Journal of Electrical Engineering and Computer Sciences
Mobile Ad-hoc NETworks (MANETs) are expected to play an important role in tactical military networks by providing infrastructureless communication. However, maintaining secure and instant information sharing is a difficult task especially for highly dynamic military MANETs. To address this requirement, we propose a new multi-tier adaptive military MANET security protocol using hybrid cryptography and signcryption. In our protocol, we bring novelties to secure military MANET communication for three main points: Cryptographic methods used in MANETs, hybrid key management protocols and structural organization of the military MANETs. As a new approach, we use hybrid cryptography mechanisms and Elliptic Curve Pintsov-Vanstone Signature …
Determination Of Autoregressive Model Orders For Seizure Detection, Serap Aydin
Determination Of Autoregressive Model Orders For Seizure Detection, Serap Aydin
Turkish Journal of Electrical Engineering and Computer Sciences
In the present study, a step-wise least square estimation algorithm (SLSA), implemented in a Matlab package called as ARfit, has been newly applied to clinical data for estimation of the accurate Auto-Regressive (AR) model orders of both normal and ictal EEG series where the power spectral density (PSD) estimations are provided by the Burg Method. The ARfit module is found to be usefull in comparison to a large variety of traditional methods such as Forward Prediction Error (FPE), Akaike's Information Criteria (AIC), Minimum Description Lenght (MDL), and Criterion of Autoregressive Transfer function (CAT) for EEG discrimination. According to tests, the …
Effect Of Transformer On Stochastic Estimation Of Voltage Sag Due To Faults In The Power System: A Pscad/Emtdc Simulation, Nita R. Patne, K. L. Thakre
Effect Of Transformer On Stochastic Estimation Of Voltage Sag Due To Faults In The Power System: A Pscad/Emtdc Simulation, Nita R. Patne, K. L. Thakre
Turkish Journal of Electrical Engineering and Computer Sciences
Voltage sags in the electric power system are mostly due to faults in the power system. Voltage sag is characterized by its magnitude (the retained voltage), phase-angle jump, unbalance in the sag in the three phases, and duration. Type of transformers in the electrical system is the important parameter influencing the characteristic of sag at the node where sensitive loads are connected. For sensitive loads it is necessary to estimate how many times in a year the voltage at their terminal will experience sag to avoid tripping of operation. In this paper the effect of transformer on stochastic estimation of …
Adaptive Hysteresis Band Control For Constant Switching Frequency In Dtc Induction Machine Drives, H. İbrahi̇m Okumuş, Mustafa Aktaş
Adaptive Hysteresis Band Control For Constant Switching Frequency In Dtc Induction Machine Drives, H. İbrahi̇m Okumuş, Mustafa Aktaş
Turkish Journal of Electrical Engineering and Computer Sciences
It is fairly well known that direct torque control (DTC) exhibits fast dynamic torque response, a property that originates in the fact that torque and flux is directly controlled by instantaneous space voltage vector, unlike field-oriented control. For this reason direct torque control gradually has been used in the field, eliciting quick response and high efficiency since its introduction in the mid-1980s. Conventional fixed band hysteresis control has several problems. One of these is variable switching frequency, which causes serious problems in DTC. In this paper, an adaptive hysteresis band control strategy is proposed, where the hysteresis band is controlled …
Improved Analytical Modulation Transfer Function For Image Intensified Charge Coupled Devices*, Nebi̇ Gül, Murat Efe
Improved Analytical Modulation Transfer Function For Image Intensified Charge Coupled Devices*, Nebi̇ Gül, Murat Efe
Turkish Journal of Electrical Engineering and Computer Sciences
The basic problem of simulation and modeling of Image Intensified Charge Coupled Device (ICCD) is the difference between the analytical Modulation Transfer Function (MTF) formulation used in the model and the experimentally obtained MTF. An investigation into the MTF of ICCD sub-components reveal that the MTF of the Image Intensifier Tube (IIT) is the main factor in this deviation. In this study, a regulation factor for the MTF of 3^{rd} generation IITs has been developed. A commonly used MTF formulation for IITs has been modified to include a regulation factor which has helped produce more precise MTF values for the …
Building Linear Parameter Varying Models Using Adaptation, For The Control Of A Class Of Nonlinear Systems, Coşku Kasnakoğlu
Building Linear Parameter Varying Models Using Adaptation, For The Control Of A Class Of Nonlinear Systems, Coşku Kasnakoğlu
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper a novel method is proposed for constructing linear parameter varying (LPV) system models through adaptation. For a class of nonlinear systems, an LPV model is built using its linear part, and its coefficients are considered as time-varying parameters. The variation in time is controlled by an adaptation scheme with the goal of keeping the trajectories of the LPV system close to those of the original nonlinear system. Using the LPV model as a surrogate, a dynamical controller is built by utilizing self-scheduling methods for LPV systems, and it is shown that this controller will indeed stabilize the …
P2p Collaborative Filtering With Privacy, Ci̇han Kaleli̇, Hüseyi̇n Polat
P2p Collaborative Filtering With Privacy, Ci̇han Kaleli̇, Hüseyi̇n Polat
Turkish Journal of Electrical Engineering and Computer Sciences
With the evolution of the Internet and e-commerce, collaborative filtering (CF) and privacy-preserving collaborative filtering (PPCF) have become popular. The goal in CF is to generate predictions with decent accuracy, efficiently. The main issue in PPCF, however, is achieving such a goal while preserving users' privacy. Many implementations of CF and PPCF techniques proposed so far are centralized. In centralized systems, data is collected and stored by a central server for CF purposes. Centralized storage poses several hazards to users because the central server controls users' data. In this work, we investigate how to produce naïve Bayesian classifier (NBC)-based recommendations …
Comparison Of Daubechies Wavelets For Hurst Parameter Estimation, Cebrai̇l Çi̇ftli̇kli̇, Ali̇ Gezer
Comparison Of Daubechies Wavelets For Hurst Parameter Estimation, Cebrai̇l Çi̇ftli̇kli̇, Ali̇ Gezer
Turkish Journal of Electrical Engineering and Computer Sciences
Time scale dependence on the working nature of wavelet analysis makes it a valuable tool for Hurst parameter estimation. Similar to other wavelet-based signal processing applications, the selection of a particular wavelet type and vanishing moment in wavelet based Hurst estimation is a challenging problem. In this paper, we investigate the best Daubechies wavelet in wavelet based Hurst estimation for an exact self similar process, fractional Gaussian noise and how Daubechies vanishing moment affects the Hurst estimation accuracy. Daubechies wavelets are preferred in analysis because increasing vanishing moment does not cause excessive increase of time support of Daubechies wavelets. Thus, …
A Novel Square-Root Domain Realization Of First Order All-Pass Filter, Si̇nem Ölmez, Uğur Çam
A Novel Square-Root Domain Realization Of First Order All-Pass Filter, Si̇nem Ölmez, Uğur Çam
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, a new square-root domain, first order, all-pass filter based on the MOSFET square law is presented. The proposed filter is designed by using nonlinear mapping on the state variables of a state space description of the transfer function. To the best knowledge of the authors, the filter is the first square-root domain first order all-pass structure designed by using state space synthesis method in the literature. The center frequency of the all-pass filter is not only attainable at megahertz frequencies but also tunable by an external bias current. The proposed filter operated 2.5 V supply voltage is …
Robust Multimedia Watermarking: Hidden Markov Model Approach For Video Sequences, Ersi̇n Elbaşi
Robust Multimedia Watermarking: Hidden Markov Model Approach For Video Sequences, Ersi̇n Elbaşi
Turkish Journal of Electrical Engineering and Computer Sciences
Because of the large amount of frames, similarity between frames and temporal attacks (frame dropping, frame averaging, frame swapping etc.), the process for video watermarking is more difficult than that for image watermarking. Current image watermarking methods are limited to solve all these difficulties. We propose a novel video watermarking system based on the Hidden Markov Model (HMM). This novel watermarking scheme splits the video sequences into a Group of Pictures (GOP) with HMM. Portions of the binary watermark are embedded into each GOP with a wavelet domain watermarking algorithm. The embedding process is the standard additive algorithm [1] in …
A New Chaotic Attractor From General Lorenz System Family And Its Electronic Experimental Implementation, İhsan Pehli̇van, Yilmaz Uyaroğlu
A New Chaotic Attractor From General Lorenz System Family And Its Electronic Experimental Implementation, İhsan Pehli̇van, Yilmaz Uyaroğlu
Turkish Journal of Electrical Engineering and Computer Sciences
This article introduces a novel three-dimensional continuous autonomous chaotic system with six terms and two quadratic nonlinearities. The new system contains two variational parameters and exhibits Lorenz-like attractors in numerical simulations and experimental measurements. The basic dynamical properties of the new system are analyzed by means of equilibrium points, eigenvalue structures, and Lyapunov exponents. The new system examined in Matlab-Simulink^{\textregistered} and Orcad-PSpice^{\textregistered}. An electronic circuit realization of the proposed system is presented using analog electronic elements such as capacitors, resistors, operational amplifiers and multipliers. The behaviour of the realized system is evaluated with computer simulations.
Stator Resistance Estimation Using Ann In Dtc Im Drives, Mustafa Aktaş, H. İbrahi̇m Okumuş
Stator Resistance Estimation Using Ann In Dtc Im Drives, Mustafa Aktaş, H. İbrahi̇m Okumuş
Turkish Journal of Electrical Engineering and Computer Sciences
Torque control of induction motors (IM) requires accurate estimation of the flux in the motor. But the flux estimate, when estimated from the stator circuit variables, is highly dependent on the stator resistance of the IM. As a result, the flux estimate is prone to errors due to variation in the stator resistance, especially at low stator frequencies. In this paper, an Artificial Neural Network (ANN) is used to adjust the stator resistance of an IM. A back propagation training algorithm was used in training the neural network for the simulation. The proposed ANN resistance estimator has shown good performance …
Stochastic Stability Of The Discrete-Time Constrained Extended Kalman Filter, Levent Özbek, Esi̇n Köksal Babacan, Murat Efe
Stochastic Stability Of The Discrete-Time Constrained Extended Kalman Filter, Levent Özbek, Esi̇n Köksal Babacan, Murat Efe
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, stability of the projection-based constrained discrete-time extended Kalman filter (EKF) as applied to nonlinear systems in a stochastic framework has been studied. It has been shown that like the unconstrained EKF, the estimation error of the EKF with known constraints on the states remains bounded when the initial error and noise terms are small, and the solution of the Riccati difference equation remains positive definite and bounded. Stability results are verified and performance of the constrained EKF is demonstrated through simulations on a nonlinear engineering example.
Artificial Neural Network Based Chaotic Generator For Cryptology, İlker Dalkiran, Kenan Danişman
Artificial Neural Network Based Chaotic Generator For Cryptology, İlker Dalkiran, Kenan Danişman
Turkish Journal of Electrical Engineering and Computer Sciences
Chaotic systems are sensitive to initial conditions, system parameters and topological transitivity and these properties are also remarkable for cryptanalysts. Noise like behavior of chaotic systems is the main reason of using these systems in cryptology. However some properties of chaotic systems such as synchronization, fewness of parameters etc. cause serious problems for cryptology. In this paper, to overcome disadvantages of chaotic systems, the dynamics of Chua's circuit namely x, y and z were modeled using Artificial Neural Network (ANN). ANNs have some distinctive capabilities like learning from experiences, generalizing from a few data and nonlinear relationship between inputs and …
K-Anonymity Based Framework For Privacy Preserving Data Collection In Wireless Sensor Networks, Hayretdi̇n Bahşi̇, Albert Levi̇
K-Anonymity Based Framework For Privacy Preserving Data Collection In Wireless Sensor Networks, Hayretdi̇n Bahşi̇, Albert Levi̇
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, k-anonymity notion is adopted to be used in wireless sensor networks (WSN) as a security framework with two levels of privacy. A base level of privacy is provided for the data shared with semi-trusted sink and a deeper level of privacy is provided against eavesdroppers. In the proposed method, some portions of data are encrypted and the rest is generalized. Generalization shortens the size of the data transmitted in the network causing energy saving at the cost of information loss. On the other hand, encryption provides anonymization with no information loss and without saving energy. Thus, there …
The Effect Of The Channel Reliability Factor In The Map Algorithm On Turbo Code Performance In Bluetooth Systems, Sali̇m Kahveci̇, İsmai̇l Kaya
The Effect Of The Channel Reliability Factor In The Map Algorithm On Turbo Code Performance In Bluetooth Systems, Sali̇m Kahveci̇, İsmai̇l Kaya
Turkish Journal of Electrical Engineering and Computer Sciences
The effects of the channel reliability factor on the performance of turbo decoders that use a maximum a posteriori probability algorithm are investigated for wireless communication fading channels, such as Bluetooth systems. The channel reliability factor is related to the channel signal-to-noise ratio. For various values of the channel reliability factor, the obtained performance curves of the maximum a posteriori probability algorithm are given for the case of DMx Bluetooth data packets. When the channel reliability factor increases, the bit-error-rate performance of the DMx Bluetooth data packets also increases over fading channels.
Relativistic Electromagnetism In Rotating Media, Pierre Hillion
Relativistic Electromagnetism In Rotating Media, Pierre Hillion
Turkish Journal of Electrical Engineering and Computer Sciences
This work concerns relativistic electromagnetism in a cylindrical Frenet-Serret frame. The tensor formalism of Maxwell's equations and electromagnetic fields in a vacuum is first developed in terms of cylindrical coordinates and afterwards applied to a rotating frame using the relativistic Trocheris-Takeno description of rotations. The metric ds^2 = g_{\mu \nu} dx^{\mu} dx^{\nu} of this frame is then obtained to find the determinant g of the g_{\mu \nu} matrix intervening in the relativistic Maxwell's equations, where the Greek indices take on the values 1,2,3,4. The propagation of harmonic cylindrical waves in rotating media is analyzed and it is shown that these …
The Effect Of Heat On The Metallurgical Structure And B-H Characteristic Of (Stator) Armature With Iron-Silicon Alloy In Electric Machines, Fevzi̇ Kentli̇, Ümi̇t Kemaletti̇n Terzi̇
The Effect Of Heat On The Metallurgical Structure And B-H Characteristic Of (Stator) Armature With Iron-Silicon Alloy In Electric Machines, Fevzi̇ Kentli̇, Ümi̇t Kemaletti̇n Terzi̇
Turkish Journal of Electrical Engineering and Computer Sciences
Coils in electric machines are varnished for insulation after winding. These varnished coils are formed in stiff construction in slots. Under heavy-duty operating conditions, all or part of some coils may be burnt or broken. Thermal method is one of several ways to remove the defective coils. In this method, current is passed through the defective coils by an autotransformer (variac) until all the varnish of the coils is burned. If all the coils are out of order, the varnish is burned by replacing the stator or armature in a burning room. Consequently, defective coils in the stator (armature) slots …
A Power Quality Monitoring System Based On Matlab Server Pages, Bülent Vural, Ali̇ Kizil, Mehmet Uzunoğlu
A Power Quality Monitoring System Based On Matlab Server Pages, Bülent Vural, Ali̇ Kizil, Mehmet Uzunoğlu
Turkish Journal of Electrical Engineering and Computer Sciences
The power quality (PQ) requirement is one of the most important issues for power companies and their customers. Continuously monitoring the PQ from remote and distributed centers will help to improve the PQ. In this study, a remote power quality monitoring system for low voltage sub-networks is developed using MATLAB Server Pages (MSP). MATLAB Server Pages, which is an open source technical web programming language, combines MATLAB with integrated J2EE specifications. The proposed PQ monitoring system uses the MATLAB HTML tag library and the data captured by the DAQ hardware to evaluate the Power Quality parameters. The proposed system can …
Nonlinear Dynamic Analysis Of Mitral Valve Doppler Signals: Surrogate Data Analysis, Esma Uzunhi̇sarcikli
Nonlinear Dynamic Analysis Of Mitral Valve Doppler Signals: Surrogate Data Analysis, Esma Uzunhi̇sarcikli
Turkish Journal of Electrical Engineering and Computer Sciences
In our study, the nonlinear dynamics of mitral valve Doppler signals from 32 healthy and 28 patients with mitral valve stenosis was evaluated using by the computation of Lyapunov exponents, correlation dimension values and surrogate data analysis. Two chaotic features are compared for healthy and patient subjects. It was found that the largest Lyapunov exponent and correlation dimension values derived from patient subjects were larger than that of healthy subjects (\rho < 0.005). Surrogate data analysis was performed to determine the chaotic dynamics of Doppler signals. It was observed that the original and surrogate data have similar spectral features. Receiver operating characteristic (ROC) curves were used to evaluate the nonlinearity character Area Under the curve (AUC) values were obtained as 0.99 and 0.978 for the largest Lyapunov exponent and correlation dimension values, respectively. According to these results, Doppler signals have a nonlinear dynamic property and the largest Lyapunov exponent. Correlation dimension features can be used to detect the change in blood flow velocity of patients with mitral valve stenosis.
Remote Sensing Applications Of Hf Skywave Radar: The Australian Experience, Stuart Anderson
Remote Sensing Applications Of Hf Skywave Radar: The Australian Experience, Stuart Anderson
Turkish Journal of Electrical Engineering and Computer Sciences
Australia has conducted research into over-the-horizon radar (OTHR) for almost sixty years. Early programs focused exclusively on military capabilities, such as the detection of aircraft, missiles and ships, but in 1974 a team was formed to design a new OTHR for which a remote sensing mission was proposed. Oceanic wind mapping experiments in 1977-78 yielded promising results so remote sensing became a recognised mission assigned to the new radar, known as Jindalee Stage B. This capability was progressively expanded over the period 1982-87 to include mapping of wave height and other oceanographic variables. A real-time data link to the Australian …
Dual-Use Of Compact Hf Radars For The Detection Of Mid- And Large-Size Vessels, Hugh Roarty, Don Barrick, Josh Kohut, Scott Glenn
Dual-Use Of Compact Hf Radars For The Detection Of Mid- And Large-Size Vessels, Hugh Roarty, Don Barrick, Josh Kohut, Scott Glenn
Turkish Journal of Electrical Engineering and Computer Sciences
This paper describes the development of the SeaSonde High Frequency Radar system into a dual-use application for the mapping of ocean surface currents and detection of ships at sea. This development entailed the creation of a new radar waveform that would permit this dual-use as well as a detection algorithm to identify the ships in the radar spectra. The detection algorithm utilizes two methods for calculating a background signal level: an infinite impulse response (IIR) filter and a two-dimensional median filter. These two methods are employed simultaneously with multiple length averaging times to maximize the number of detections. The initial …
A Review Of High Frequency Surface Wave Radar For Detection And Tracking Of Ships, Tony Ponsford, Jian Wang
A Review Of High Frequency Surface Wave Radar For Detection And Tracking Of Ships, Tony Ponsford, Jian Wang
Turkish Journal of Electrical Engineering and Computer Sciences
In today's resource-driven economy, maritime nations are claiming economic borders that extend beyond the continental shelf or the 200 nautical mile (nm) Exclusive Economic Zone (EEZ). However, claiming such large economic area places responsibilities on the parent nation to exercise jurisdiction through surveillance and enforcement. The requirement to see beyond the horizon has long been a goal of maritime security forces. Today, this is largely dependent on cooperative vessels voluntarily communicating their intentions to local shore-side authorities, as well as on those vessel sightings reported by patrollers. Recent advances in technology provide maritime nations with options to provide more systematic …
Nonlinear Scattering At Hf: Prospects For Exploitation In Oth Radar Systems, Stuart Anderson
Nonlinear Scattering At Hf: Prospects For Exploitation In Oth Radar Systems, Stuart Anderson
Turkish Journal of Electrical Engineering and Computer Sciences
HF skywave `over-the-horizon' radars experience exceptionally high levels of clutter from the earth's surface as a consequence of their `look-down' propagation geometry. While Doppler processing is effective in separating aircraft echoes from the clutter, thereby enabling detection, the same does not always hold for slow moving targets. In particular, ship echoes occupy the same region of Doppler space as the sea clutter, so the likelihood of target echo obscuration is high. By exploiting the known dependence of the characteristic spectral form of the clutter Doppler spectrum on radar frequency and other parameters, HF radars can maximise the prospects for detectability …
Radar Cross-Section (Rcs) Analysis Of High Frequency Surface Wave Radar Targets, Gonca Çakir, Levent Sevgi̇
Radar Cross-Section (Rcs) Analysis Of High Frequency Surface Wave Radar Targets, Gonca Çakir, Levent Sevgi̇
Turkish Journal of Electrical Engineering and Computer Sciences
Realistic high frequency surface wave radar (HFSWR) targets are investigated numerically in terms of electromagnetic wave -- target interactions. Radar cross sections (RCS) of these targets are simulated via both the finite-difference time-domain (FDTD) method and the Method of Moments (MoM). The virtual RCS prediction tool that was introduced in previous work is used for these investigations. The virtual tool automatically creates the discrete FDTD model of the target under investigation and performs the FDTD RCS analysis. It also automatically constructs a MoM wire grid model of the target; therefore, it is also possible to compare FDTD results against the …
Propagation Modeling And Path Loss Prediction Tools For High Frequency Surface Wave Radars, Gökhan Apaydin, Levent Sevgi̇
Propagation Modeling And Path Loss Prediction Tools For High Frequency Surface Wave Radars, Gökhan Apaydin, Levent Sevgi̇
Turkish Journal of Electrical Engineering and Computer Sciences
Propagation modeling and simulation approaches for the use of High Frequency Surface Wave Radar (HFSWR) are discussed. HFSWR uses vertically polarized surface waves along multi-mixed paths in the lower HF band (3 MHz - 15 MHz). Various numerical propagators are reviewed with an early analytical model. Split Step Fast Fourier Transformation, finite- difference, and finite-element solutions of the well-known one-way, forward propagation Parabolic Equation (PE) model are presented. MATLAB-based numerical propagation prediction tools based on these models are listed. Tests and comparisons among these analytical and numerical tools are given for some canonical surface wave propagation scenarios. The Millington effect …