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Underground Phased Arrays And Beamforming Applications, Abdul Salam, Usman Raza 2020 Purdue University

Underground Phased Arrays And Beamforming Applications, Abdul Salam, Usman Raza

Computer Information Technology Faculty Publications

This chapter presents a framework for adaptive beamforming in underground communication. The wireless propagation is thoroughly analyzed to develop a model using the soil moisture as an input parameter to provide feedback mechanism while enhancing the system performance. The working of array element in the soil is analyzed. Moreover, the effect of soil texture and soil moisture on the resonant frequency and return loss is studied in detail. The wave refraction from the soil–air interface highly degrades the performance of the system. Furthermore, to beam steering is done to achieve high gain for lateral component improving the UG communication. The …


Current Advances In Internet Of Underground Things, Abdul Salam, Usman Raza 2020 Purdue University

Current Advances In Internet Of Underground Things, Abdul Salam, Usman Raza

Computer Information Technology Faculty Publications

The latest developments in Internet of Underground Things are covered in this chapter. First, the IOUT Architecture is discussed followed by the explanation of the challenges being faced in this paradigm. Moreover, a comprehensive coverage of the different IOUT components is presented that includes communications, sensing, and system integration with the cloud. An in-depth coverage of the applications of the IOUT in various disciplines is also surveyed. These applications include areas such as decision agriculture, pipeline monitoring, border control, and oil wells.


Electromagnetic Characteristics Of The Soil, Abdul Salam, Usman Raza 2020 Purdue University

Electromagnetic Characteristics Of The Soil, Abdul Salam, Usman Raza

Computer Information Technology Faculty Publications

The electromagnetic characteristics of the soil are discussed in this chapter. The characteristics of porous bedrock, soil medium, and impacts of rain attenuations are also presented. The models of dielectric soil properties are studied with a rigorous focus on the constitutive parameters of subsurface soil medium. Moreover, the permittivity and wavenumber in soil are explained. In addition, the frequency-dependent dielectric properties such as dispersion in soil, absorption characteristic, and penetration depth versus frequency are reviewed. Furthermore, the effective permittivity of soil–water mixture for through-the soil-propagation mechanism is analyzed thoroughly.


Soil Moisture And Permittivity Estimation, Abdul Salam, Usman Raza 2020 Purdue University

Soil Moisture And Permittivity Estimation, Abdul Salam, Usman Raza

Computer Information Technology Faculty Publications

The soil moisture and permittivity estimation is vital for the success of the variable rate approaches in the field of the decision agriculture. In this chapter, the development of a novel permittivity estimation and soil moisture sensing approach is presented. The empirical setup and experimental methodology for the power delay measurements used in model are introduced. Moreover, the performance analysis is explained that includes the model validation and error analysis. The transfer functions are reported as well for soil moisture and permittivity estimation. Furthermore, the potential applications of the developed approach in different disciplines are also examined.


Autonomous Irrigation Management In Decision Agriculture, Abdul Salam, Usman Raza 2020 Purdue University

Autonomous Irrigation Management In Decision Agriculture, Abdul Salam, Usman Raza

Computer Information Technology Faculty Publications

In this chapter, the important application of autonomous irrigation management in the field decision agriculture is discussed. The different types of sensor-guided irrigation systems are presented that includes center pivot systems and drip irrigation systems. Their sensing and actuator components are with detailed focus on real-time decision-making and integration to the cloud. This chapter also presents irrigation control systems which takes, as an input, soil moisture and temperature from IOUT and weather data from Internet and communicate with center pivot based irrigation systems. Moreover, the system architecture is explored where development of the nodes including sensing and actuators is presented. …


Signals In The Soil: Underground Antennas, Abdul Salam, Usman Raza 2020 Purdue University

Signals In The Soil: Underground Antennas, Abdul Salam, Usman Raza

Computer Information Technology Faculty Publications

Antenna is a major design component of Internet of Underground Things (IOUT) communication system. The use of antenna, in IOUT, differs from traditional communication in that it is buried in the soil. Therefore, one of the main challenges, in IOUT applications, is to establish a reliable communication. To that end, there is a need of designing an underground-specific antenna. Three major factors that can impact the performance of a buried antenna are: (1) effect of high soil permittivity changes the wavelength of EM waves, (2) variations in soil moisture with time affecting the permittivity of the soil, and (3) difference …


Wireless Underground Channel Modeling, Abdul Salam, Usman Raza 2020 Purdue University

Wireless Underground Channel Modeling, Abdul Salam, Usman Raza

Computer Information Technology Faculty Publications

A comprehensive treatment of wireless underground channel modeling is presented in this chapter. The impacts of the soil on bandwidth and path loss are analyzed. A mechanism for the UG channel sounding and multipath characteristics analysis is discussed. Moreover, novel time-domain impulse response model for WUC is reviewed with the explanation of model parameters and statistics. Furthermore, different types of the through-the-soil wireless communications are surveyed. Finally, the chapter concludes with discussion of the UG wireless statistical model and path loss model for through-the-soil wireless communications in decision agriculture. The model presented in this chapter is also validated with empirical …


Signals In The Soil: An Introduction To Wireless Underground Communications, Abdul Salam, Usman Raza 2020 Purdue University

Signals In The Soil: An Introduction To Wireless Underground Communications, Abdul Salam, Usman Raza

Computer Information Technology Faculty Publications

In this chapter, wireless underground (UG) communications are introduced. A detailed overview of WUC is given. A comprehensive review of research challenges in WUC is presented. The evolution of underground wireless is also discussed. Moreover, different component of UG communications is wireless. The WUC system architecture is explained with a detailed discussion of the anatomy of an underground mote. The examples of UG wireless communication systems are explored. Furthermore, the differences of UG wireless and over-the-air wireless are debated. Different types of wireless underground channel (e.g., In-Soil, Soil-to-Air, and Air-to-Soil) are reported as well.


Model-Based And Data-Driven Situational Awareness For Distribution System Monitoring And Control, Ying Zhang 2020 Southern Methodist University

Model-Based And Data-Driven Situational Awareness For Distribution System Monitoring And Control, Ying Zhang

Electrical Engineering Theses and Dissertations

Electric power systems are undergoing a dramatic change. The penetration of distributed energy resources (DERs) such as wind turbine generators and photovoltaic panels is turning a traditional power system into the active distribution network. Power system situational awareness, which provides critical information for system monitoring and control, is being challenged by multiple sources of uncertainties such as random meter errors, stochastic power output of DERs, and imprecise network parameters. On the other hand, cyber-physical power system operation is vulnerable to cyberattacks against effective state estimation, such as false data injection attacks (FDIAs). To construct next-generation smart grids, this dissertation develops …


Signals And Systems, Jingxian Wu 2020 University of Arkansas, Fayetteville

Signals And Systems, Jingxian Wu

Open Educational Resources

Signals and Systems is a core Electrical Engineering undergraduate course. This course covers the topics of signal and system analysis, with an emphasis on the analysis of linear time-invariant systems. The materials presented in this course are designed for a 15-week course for junior or senior level students. The open access materials for this course include:

Course outline and guides: a detailed guideline that provides a week-by-week teaching schedule for a 15-week semester.

Lecture notes: a complete set of lecture notes with detailed explanations and a large number of examples that cover all the contents that are offered in this …


Wideband Satcom Model: Evaluation Of Numerical Accuracy And Efficiency, Andrew J. Knisely, Andrew Terzuoli 2020 Air Force Institute of Technology

Wideband Satcom Model: Evaluation Of Numerical Accuracy And Efficiency, Andrew J. Knisely, Andrew Terzuoli

Faculty Publications

The spectral method is typically applied as a simple and efficient method to solve the parabolic wave equation in phase screen scintillation models. The critical factors that can greatly affect the spectral method accuracy is the uniformity and smoothness of the input function. This paper observes these effects on the accuracy of the finite difference and the spectral methods applied to a wideband SATCOM signal propagation model simulated in the ultra-high frequency (UHF) band. The finite difference method uses local pointwise approximations to calculate a derivative. The spectral method uses global trigonometric interpolants that achieve remarkable accuracy for continuously differentiable …


Intelligent Algorithm For Trapezoidal Interval Valued Neutrosophic Network Analysis, Florentin Smarandache, Said Broumi, Deivanayagampillai Nagarajan, Malayalan Lathamaheswari, Mohamed Talea, Assia Bakali 2020 University of New Mexico

Intelligent Algorithm For Trapezoidal Interval Valued Neutrosophic Network Analysis, Florentin Smarandache, Said Broumi, Deivanayagampillai Nagarajan, Malayalan Lathamaheswari, Mohamed Talea, Assia Bakali

Branch Mathematics and Statistics Faculty and Staff Publications

The shortest path problem has been one of the most fundamental practical problems in network analysis. One of the good algorithms is Bellman-Ford, which has been applied in network, for the last some years. Due to complexity in the decision-making process, the decision makers face complications to express their view and judgment with an exact number for single valued membership degrees under neutrosophic environment. Though the interval number is a special situation of the neutrosophic, it did not solve the shortest path problems in an absolute manner. Hence, in this work, the authors have introduced the score function and accuracy …


A Framework To Support Automatic Certification For Self-Adaptive Systems, Ioannis Nearchou 2020 Western Michigan University

A Framework To Support Automatic Certification For Self-Adaptive Systems, Ioannis Nearchou

Masters Theses

Presently, cyber-physical systems are increasingly being integrated into societies, from the economic sector to the nuclear energy sector. Cyber-physical systems are systems that combine physical, digital, human, and other components, which operate through physical means and software. When system errors occur, the consequences of malfunction could negatively impact human life. Academic studies have relied on the MAPE-K feedback loop model to develop various system components to satisfy the self-adaptive features, such that violation of the safety requirements can be minimized. Assurance of system requirement satisfaction is argued through an industrial standard form, called an assurance case, which is usually applied …


Hybrid Microwave Power Amplifiers For Broadband Communication, Sangaran Pragash 2020 Universiti Malaya

Hybrid Microwave Power Amplifiers For Broadband Communication, Sangaran Pragash

Student Works (2020-2029)

The software-defined radio is the future of radio technology. The development of a broadband power amplifier is the most challenging radio component to design in achieving software-defined radio goals due to the PA gain-bandwidth limitation. The distributed power amplifier (DPA) overcomes the limitation by combining output power from several transistors in an additive fashion. Matrix Amplifier (MA) consists of two or more DPA stacked together in a multiplicative manner. In this project, a high power and high gain DPA for a two-way radio system is demonstrated. The DPA exhibits 10W output power and 32dB gain across the frequency range of …


Design Of A Sweeping Impedance Probe For The Sport Mission, Caleb W. Young 2020 Utah State University

Design Of A Sweeping Impedance Probe For The Sport Mission, Caleb W. Young

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In our modern world satellite systems are an evermore common part of day to day life. Reliable communication from the ground to these satellites is becoming more and more necessary. Plasma scintillations in the ionosphere can make these communications difficult or even impossible. By gaining a better understanding of these scintillations, times of bad satellite connection can be predicted in the same way terrestrial weather gets predicted and reported today. The objective of the SPORT mission is to gain a better understanding of these plasma scintillations. In order to measure plasma density, and gain a better understanding of plasma scintillations, …


Organic Materials As Saturable Absorber For Pulse Generation At Telecommunication Window, Mohammed Hussein Sameer Salam M.H. 2020 Universiti Malaya

Organic Materials As Saturable Absorber For Pulse Generation At Telecommunication Window, Mohammed Hussein Sameer Salam M.H.

Student Works (2020-2029)

This thesis demonstrates several types of fiber lasers based on newly developed organic materials as saturable absorbers (SAs). We used these SAs in all-fiber based erbium-doped fiber laser (EDFL) ring cavity to produce Q-switched and mode-locked pulses at telecommunication window, at ~ 1560 nm. Three different organic materials were used in this thesis: Bis[2-(4,6-difluorophenyl)pyridinato-C2 ,N](picolinato)iridium(III) (FIrpic), bis(8-hydroxyquinoline)zinc (Znq2) and Tris(8-hydroxyquinoline)aluminum (Alq3). Finding new materials is still one of the defining characteristics of nonlinear optics field, as the rapid development of SAs has provided several new opportunities for nonlinear optics. Throughout this work, organic material showed a very interesting performance in …


Analysis Of Protection System Setting In 11kv Distribution System, Alamshah Ammar 2020 Universiti Malaya

Analysis Of Protection System Setting In 11kv Distribution System, Alamshah Ammar

Student Works (2020-2029)

One of the fundamental protections used in electrical network power system is Overcurrent and Earth Fault (OCEF) protection. They have to be both sensitive and quick in minimizing the electrodynamic and thermal stress imposed on the equipment during the fault time interval. It is utmost important for the relays to be capable of removing only the faulty section while keep up the flexibly to solid areas in the system. In order to achieve this objective, correct relay coordination setting is important to prevent the system from suffering catastrophic effects. These days, the consumer is enforcing raising performance demands by reducing …


Fault Location In Distribution System Based On Voltage Sag Analysis, Ahmad Muhamad Firdaus 2020 Universiti Malaya

Fault Location In Distribution System Based On Voltage Sag Analysis, Ahmad Muhamad Firdaus

Student Works (2020-2029)

Fault in the distribution system is something that cannot be avoided. It is a recurring event that occurs due to various factors such as natural occurrence, mechanism failure, or human error. All this contributes to the phenomenon that will affect the stability of the system and result in the loss of power to the consumers. However, such a fault is something that happens unexpectedly, and it is difficult to be eliminated. Therefore, various research work has been done over the years to overcome the problem. All research is done to find the most effective method of finding the fault location …


A Novel Path Loss Forecast Model To Support Digital Twins For High Frequency Communications Networks, James Marvin Taylor Jr. 2020 University of Nebraska-Lincoln

A Novel Path Loss Forecast Model To Support Digital Twins For High Frequency Communications Networks, James Marvin Taylor Jr.

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

The need for long-distance High Frequency (HF) communications in the 3-30 MHz frequency range seemed to diminish at the end of the 20th century with the advent of space-based communications and the spread of fiber optic-connected digital networks. Renewed interest in HF has emerged as an enabler for operations in austere locations and for its ability to serve as a redundant link when space-based and terrestrial communication channels fail. Communications system designers can create a “digital twin” system to explore the operational advantages and constraints of the new capability. Existing wireless channel models can adequately simulate communication channel conditions with …


Methods For Ensuring The Stability Of Design Reliability In Rural Telecommunications Network During Its Operation, Akbar Daniyarovich Normurodov Mr. 2020 Tashkent University of Information Technology Address: 108 Amir Temur st.,100000, Tashkent city, Republic of Uzbekistan E-mail: [email protected], Phone: +998977161969.

Methods For Ensuring The Stability Of Design Reliability In Rural Telecommunications Network During Its Operation, Akbar Daniyarovich Normurodov Mr.

Chemical Technology, Control and Management

The article discusses methods to ensure the stability of the design reliability of a rural telecommunications network during its operation. In rural areas, for a number of reasons, the power supply from the power supply network is interrupted at random times. In this regard, backup power sources are provided for the power supply of OLT equipment. To provide a telecommunication network with stable power supply, it is proposed to use solar sources of electricity.


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