"Unmanned Aerial Vehicles (UAVs) have been widely used in modern warfare for surveillance, reconnaissance and even attack missions. They can provide valuable battlefield information and accomplish dangerous tasks with minimal risk of loss of lives and personal injuries. However, existing UAV systems are far from perfect to meet all possible situations. One of the most notable situations is the support for individual troops. Besides the incapability to always provide images in desired resolution, currently available systems are either too expensive for large-scale deployment or too heavy and complex for a single solder. Intelligent Portable Aerial Surveillance System (IPASS), sponsored by the Air Force Research Laboratory (AFRL), is aimed at developing a low-cost, light-weight unmanned aerial vehicle that can provide sufficient battlefield intelligence for individual troops. The main contributions of this thesis are two-fold (1) the development and verification of a model-based flight simulation for the aircraft, (2) comparison of image stitching techniques to provide a comprehensive aerial surveillance information from multiple vision. To assist with the design and control of the aircraft, dynamical models are established at different complexity levels. Simulations with these models are implemented in Matlab to study the dynamical characteristics of the aircraft. Aerial images acquired from the three onboard cameras are processed after getting the flying platform built. How a particular image is formed from a camera and the general pipeline of the feature-based image stitching method are first introduced in the thesis. To better satisfy the needs of this application, a homography-based stitching method is studied. This method can greatly reduce computation time with very little compromise in the quality of the panorama, which makes real-time video display of the surroundings on the ground station possible. By implementing both of the methods for image stitching using OpenCV, a quantitative comparison in the performance is accomplished."

This thesis explores the use of the Naïve Bayesian classifier as a method of determining high-level information about secondary users in a Dynamic Spectrum Access (DSA) network using a low complexity channel sensing method.  With a growing number of users generating an increased demand for broadband access, determining an efficient method for utilizing the limited available broadband is a developing current and future issue.  One possible solution is DSA, which we simulate using the Universal DSA Network Simulator (UDNS), created by our team at Virginia Tech. However, DSA requires user devices to monitor large amounts of bandwidth, and the user devices are often limited in their acceptable size, weight, and power.  This greatly limits the usable bandwidth when using complex channel sensing methods.  Therefore, this thesis focuses on energy detection for channel sensing. Constraining computing requirements by operating with limited spectrum sensing equipment allows for efficient use of limited broadband by user devices.  The research on using the Naïve Bayesian classifier coupled with energy detection and the UDNS serves as a strong starting point for supplementary work in the area of radio classification. / Master of Science

In this paper I describe a motion planning technique for intelligent ground vehicles. The technique is an implementation of a path selection algorithm based on fuzzy inference. The approach extends on the motion planning algorithm known as driving with tentacles. The selection of the tentacle (a drivable path) to follow relies on the calculation of a weighted cost function for each tentacle in the current speed set, and depends on variables such as the distance to the desired position, speed, and the closeness of a tentacle to any obstacles. A Matlab simulation and the practical implementation of the fuzzy inference rule on a Clearpath Husky robot within the Robot Operating System (ROS) framework are provided.

With the rapid development of the industry all over the world, the consumption of fossil fuel of human activities has reached an extremely high level which result in an incredible dust emission level nowadays. As one of the major environment challenges today, dust pollution has become a vital issue that the human beings have to face and resolve.    To tackle the dust pollution problem, a reliable measurement of the dust concentration level is essential. In recent years, methods with different principles are used to detect the dust concentration have been developed. The methods developed based on the scattering principle and the extinction principle for dust concentration measurement have a series of virtues such as high measurement speed, excellent precision and can be useful for real time monitoring.    This thesis reviewed the popular theories that are applied in the field which are light scattering (Mie theory) and light extinction (Lambert-beer theory). Matlab simulation is used to verify the possibility of the determined physical quantities related to the concentration measurement in the theory analysis. A new method using the ratio of scattering intensity and extinction intensity is discussed in this thesis providing a more accurate result eliminating the drawbacks of the scattering method and the extinction method.

In recent years there is growing research in optical wireless communication. This growing popularity isdue to several characteristics like such as large bandwidth that is also not having spectrum regulationsimposed, low cost and license-free operation. Since visible light communications (VLC) is a branch ofoptical wave communications (OWC), it is used for replacing RF communications. The other primaryreason for the use of visible light communications [1], because it uses 400 THz of unlicensed secure andradio free media for wireless communications which are 1000 times more than that of radiocommunications. For transmission of VLC, we use LED as light sources.Due to the high efficiency and less power consumption LED have replaced the oldfluorescence lamps, LED provide the dual functionality they can provide lighting and can providecommunications (transfer of data) just like Wi-Fi. In LED the on and off state is so fast that the humaneye can’t even perceive it. The on and off state can be taken as 1 and 0’s and through this we can transferthe data, this type of modulation is called OOK keying modulation it is used for single carrier modulationscheme. We can interpret the data that is received from the transceiver side with the help of thephotodiode at the receiver’s side. This communication technique can provide better security as there is nointerference, as light can't penetrate through walls leaving the data transfer to the room itself. ThroughVLC we can offer better security to data over RF communications.In this thesis, the implementation process has been performed in MATLABsimulations where we analyse different modulation techniques and parameters. We design a room withdimensions as 5m*5m*3m as length, width and height. We take multiple LED’s at the top and determinethe illumination parameters in the room due to the light emitted from the LED. The receiver is located ona desk and we calculate the number of data rates received at the receiver. The modulation techniques usedin this thesis are OOK keying modulation. We estimate the data rates in two methodologies directdetection (Line of sight) and also, we take reflections from the wall into consideration (Non-line of sight).The effect of data rates due to illumination and distance are also determined. In this thesis we transfer dataover the transmitter and receive the information at the receiver for obtained information the calculation of bit error rate (BER) is performed for both single LED and multiple LED array. The analysis is performed between the performance metrics of a single LED’s and multiple LED’s arrays to determine better-LEDarray.Key Words: OOK modulation scheme, MATLAB-Simulation, Light Emitting Diodes .

abstract: As the demand for renewable and alternative energy continues to increase with both large industrial companies and average homeowners, there continues to be a challenge of efficient energy storage. Several main alternative energy producers such as wind turbines, hydroelectric dams, and solar photovoltaic arrays have become more commonly used over the past decade for generating energy. One of the most common issues with these alternative energy producers is the intermittent production and supply of energy due to fluctuations in weather conditions, peak loads, and instantaneous power draw. To counteract these issues, storage units such as battery banks and proton exchange membrane fuel cells are introduced to provide electricity for the unmet energy demands. In this study, a solar photovoltaic array and fuel cell hybrid system has been set up to provide the energy needs for an average Arizona residential household. A bench test setup has revealed that a solar photovoltaic array and the fuel cell hybrid system can produce enough energy to power an Arizona household that on average consumes 37.7 kWh/d. Additionally, a Mathworks MATLAB/Simulink model of the hybrid system has been created to simulate specific scenarios which provide insight into the system’s reaction to various conditions such as varying solar irradiance and temperature variables and poor weather conditions. Finally, the economic impact of the hybrid system was simulated using HOMER Legacy to analyze the cost effectiveness of a 25-year project. / Dissertation/Thesis / Masters Thesis Engineering 2017

Speech is intuitive, fast and easy to generate, but it is hard to index and easy to forget. What is more, listening to speech is slow. Text is easier to store, process and consume, both for computers and for humans, but writing text is slow and requires some intention. In this thesis, we study speech recognition which allows converting speech into text, making it easier both to create and to use information. Our tool of study is Hidden Markov Models which is one of the most important machine learning models in speech and language processing. The aim of this thesis is to do a rst study in Hidden Markov Models and understand their importance, particularly in speech recognition. We will go through three fundamental problems that come up naturally with Hidden Markov Models: to compute a likelihood of an observation sequence, to nd an optimal state sequence given an observation sequence and the model, and to adjust the model parameters. A solution to each problem will be given together with an example and the corresponding simulations using MatLab. The main importance lies in the last example, in which a rst approach to speech recognition will be done.

This thesis is focusing on the second satellite digital TV standard, DVB-S2. It deals with the principle of the digital TV and the first standard DVB-S. It also describes the very beginning and characteristics of the DVB-S2, new technologies in use, architecture and the individual topics are then explained more in detail. The thesis also contains the program of transmission simulation of DVB-S2 in MATLAB. In the laboratory of television technology UREL, two standards were measured and compared with the values obtained from the program. The functionality of the program and the benefits of DVB-S2 were verified afterwards.

This thesis studies the Physical Layer (PHY) of the new IEEE 802.11acWireless Local Access Network (WLAN) standard. The 11ac is built basedon the 11n successful standard. The standard is expected to be completedby the end of 2013. And it promises a Very High Throughput (VHT),and robust communication. In order to achieve that, the 11ac uses morebandwidth, it employs higher numbers of Multiple-Input Multiple-Output(MIMO) spatial streams, and higher orders of modulations. The 11ac PHYframe structure is studied in details. The transmitter and receiver blocks areexplained and implemented by MATLAB. Bit Error Rate (BER) and ErrorVector Magnitude (EVM) simulations of the PHY were run. The effectof different Modulation and Coding Scheme (MCS), and bandwidths werestudied. The performance of MIMO and Space-Time Block Coding (STBC)was investigated. The simulation results shows how the 11ac benefits fromthe new employed features. The created MATLAB simulation program canbe used for further tests and research.

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